xref: /openbmc/linux/drivers/iommu/amd/init.c (revision e15a5365)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2007-2010 Advanced Micro Devices, Inc.
4  * Author: Joerg Roedel <jroedel@suse.de>
5  *         Leo Duran <leo.duran@amd.com>
6  */
7 
8 #define pr_fmt(fmt)     "AMD-Vi: " fmt
9 #define dev_fmt(fmt)    pr_fmt(fmt)
10 
11 #include <linux/pci.h>
12 #include <linux/acpi.h>
13 #include <linux/list.h>
14 #include <linux/bitmap.h>
15 #include <linux/slab.h>
16 #include <linux/syscore_ops.h>
17 #include <linux/interrupt.h>
18 #include <linux/msi.h>
19 #include <linux/amd-iommu.h>
20 #include <linux/export.h>
21 #include <linux/kmemleak.h>
22 #include <linux/mem_encrypt.h>
23 #include <asm/pci-direct.h>
24 #include <asm/iommu.h>
25 #include <asm/apic.h>
26 #include <asm/msidef.h>
27 #include <asm/gart.h>
28 #include <asm/x86_init.h>
29 #include <asm/iommu_table.h>
30 #include <asm/io_apic.h>
31 #include <asm/irq_remapping.h>
32 #include <asm/set_memory.h>
33 
34 #include <linux/crash_dump.h>
35 
36 #include "amd_iommu.h"
37 #include "../irq_remapping.h"
38 
39 /*
40  * definitions for the ACPI scanning code
41  */
42 #define IVRS_HEADER_LENGTH 48
43 
44 #define ACPI_IVHD_TYPE_MAX_SUPPORTED	0x40
45 #define ACPI_IVMD_TYPE_ALL              0x20
46 #define ACPI_IVMD_TYPE                  0x21
47 #define ACPI_IVMD_TYPE_RANGE            0x22
48 
49 #define IVHD_DEV_ALL                    0x01
50 #define IVHD_DEV_SELECT                 0x02
51 #define IVHD_DEV_SELECT_RANGE_START     0x03
52 #define IVHD_DEV_RANGE_END              0x04
53 #define IVHD_DEV_ALIAS                  0x42
54 #define IVHD_DEV_ALIAS_RANGE            0x43
55 #define IVHD_DEV_EXT_SELECT             0x46
56 #define IVHD_DEV_EXT_SELECT_RANGE       0x47
57 #define IVHD_DEV_SPECIAL		0x48
58 #define IVHD_DEV_ACPI_HID		0xf0
59 
60 #define UID_NOT_PRESENT                 0
61 #define UID_IS_INTEGER                  1
62 #define UID_IS_CHARACTER                2
63 
64 #define IVHD_SPECIAL_IOAPIC		1
65 #define IVHD_SPECIAL_HPET		2
66 
67 #define IVHD_FLAG_HT_TUN_EN_MASK        0x01
68 #define IVHD_FLAG_PASSPW_EN_MASK        0x02
69 #define IVHD_FLAG_RESPASSPW_EN_MASK     0x04
70 #define IVHD_FLAG_ISOC_EN_MASK          0x08
71 
72 #define IVMD_FLAG_EXCL_RANGE            0x08
73 #define IVMD_FLAG_IW                    0x04
74 #define IVMD_FLAG_IR                    0x02
75 #define IVMD_FLAG_UNITY_MAP             0x01
76 
77 #define ACPI_DEVFLAG_INITPASS           0x01
78 #define ACPI_DEVFLAG_EXTINT             0x02
79 #define ACPI_DEVFLAG_NMI                0x04
80 #define ACPI_DEVFLAG_SYSMGT1            0x10
81 #define ACPI_DEVFLAG_SYSMGT2            0x20
82 #define ACPI_DEVFLAG_LINT0              0x40
83 #define ACPI_DEVFLAG_LINT1              0x80
84 #define ACPI_DEVFLAG_ATSDIS             0x10000000
85 
86 #define LOOP_TIMEOUT	100000
87 /*
88  * ACPI table definitions
89  *
90  * These data structures are laid over the table to parse the important values
91  * out of it.
92  */
93 
94 extern const struct iommu_ops amd_iommu_ops;
95 
96 /*
97  * structure describing one IOMMU in the ACPI table. Typically followed by one
98  * or more ivhd_entrys.
99  */
100 struct ivhd_header {
101 	u8 type;
102 	u8 flags;
103 	u16 length;
104 	u16 devid;
105 	u16 cap_ptr;
106 	u64 mmio_phys;
107 	u16 pci_seg;
108 	u16 info;
109 	u32 efr_attr;
110 
111 	/* Following only valid on IVHD type 11h and 40h */
112 	u64 efr_reg; /* Exact copy of MMIO_EXT_FEATURES */
113 	u64 res;
114 } __attribute__((packed));
115 
116 /*
117  * A device entry describing which devices a specific IOMMU translates and
118  * which requestor ids they use.
119  */
120 struct ivhd_entry {
121 	u8 type;
122 	u16 devid;
123 	u8 flags;
124 	u32 ext;
125 	u32 hidh;
126 	u64 cid;
127 	u8 uidf;
128 	u8 uidl;
129 	u8 uid;
130 } __attribute__((packed));
131 
132 /*
133  * An AMD IOMMU memory definition structure. It defines things like exclusion
134  * ranges for devices and regions that should be unity mapped.
135  */
136 struct ivmd_header {
137 	u8 type;
138 	u8 flags;
139 	u16 length;
140 	u16 devid;
141 	u16 aux;
142 	u64 resv;
143 	u64 range_start;
144 	u64 range_length;
145 } __attribute__((packed));
146 
147 bool amd_iommu_dump;
148 bool amd_iommu_irq_remap __read_mostly;
149 
150 int amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_VAPIC;
151 static int amd_iommu_xt_mode = IRQ_REMAP_XAPIC_MODE;
152 
153 static bool amd_iommu_detected;
154 static bool __initdata amd_iommu_disabled;
155 static int amd_iommu_target_ivhd_type;
156 
157 u16 amd_iommu_last_bdf;			/* largest PCI device id we have
158 					   to handle */
159 LIST_HEAD(amd_iommu_unity_map);		/* a list of required unity mappings
160 					   we find in ACPI */
161 bool amd_iommu_unmap_flush;		/* if true, flush on every unmap */
162 
163 LIST_HEAD(amd_iommu_list);		/* list of all AMD IOMMUs in the
164 					   system */
165 
166 /* Array to assign indices to IOMMUs*/
167 struct amd_iommu *amd_iommus[MAX_IOMMUS];
168 
169 /* Number of IOMMUs present in the system */
170 static int amd_iommus_present;
171 
172 /* IOMMUs have a non-present cache? */
173 bool amd_iommu_np_cache __read_mostly;
174 bool amd_iommu_iotlb_sup __read_mostly = true;
175 
176 u32 amd_iommu_max_pasid __read_mostly = ~0;
177 
178 bool amd_iommu_v2_present __read_mostly;
179 static bool amd_iommu_pc_present __read_mostly;
180 
181 bool amd_iommu_force_isolation __read_mostly;
182 
183 /*
184  * Pointer to the device table which is shared by all AMD IOMMUs
185  * it is indexed by the PCI device id or the HT unit id and contains
186  * information about the domain the device belongs to as well as the
187  * page table root pointer.
188  */
189 struct dev_table_entry *amd_iommu_dev_table;
190 /*
191  * Pointer to a device table which the content of old device table
192  * will be copied to. It's only be used in kdump kernel.
193  */
194 static struct dev_table_entry *old_dev_tbl_cpy;
195 
196 /*
197  * The alias table is a driver specific data structure which contains the
198  * mappings of the PCI device ids to the actual requestor ids on the IOMMU.
199  * More than one device can share the same requestor id.
200  */
201 u16 *amd_iommu_alias_table;
202 
203 /*
204  * The rlookup table is used to find the IOMMU which is responsible
205  * for a specific device. It is also indexed by the PCI device id.
206  */
207 struct amd_iommu **amd_iommu_rlookup_table;
208 EXPORT_SYMBOL(amd_iommu_rlookup_table);
209 
210 /*
211  * This table is used to find the irq remapping table for a given device id
212  * quickly.
213  */
214 struct irq_remap_table **irq_lookup_table;
215 
216 /*
217  * AMD IOMMU allows up to 2^16 different protection domains. This is a bitmap
218  * to know which ones are already in use.
219  */
220 unsigned long *amd_iommu_pd_alloc_bitmap;
221 
222 static u32 dev_table_size;	/* size of the device table */
223 static u32 alias_table_size;	/* size of the alias table */
224 static u32 rlookup_table_size;	/* size if the rlookup table */
225 
226 enum iommu_init_state {
227 	IOMMU_START_STATE,
228 	IOMMU_IVRS_DETECTED,
229 	IOMMU_ACPI_FINISHED,
230 	IOMMU_ENABLED,
231 	IOMMU_PCI_INIT,
232 	IOMMU_INTERRUPTS_EN,
233 	IOMMU_DMA_OPS,
234 	IOMMU_INITIALIZED,
235 	IOMMU_NOT_FOUND,
236 	IOMMU_INIT_ERROR,
237 	IOMMU_CMDLINE_DISABLED,
238 };
239 
240 /* Early ioapic and hpet maps from kernel command line */
241 #define EARLY_MAP_SIZE		4
242 static struct devid_map __initdata early_ioapic_map[EARLY_MAP_SIZE];
243 static struct devid_map __initdata early_hpet_map[EARLY_MAP_SIZE];
244 static struct acpihid_map_entry __initdata early_acpihid_map[EARLY_MAP_SIZE];
245 
246 static int __initdata early_ioapic_map_size;
247 static int __initdata early_hpet_map_size;
248 static int __initdata early_acpihid_map_size;
249 
250 static bool __initdata cmdline_maps;
251 
252 static enum iommu_init_state init_state = IOMMU_START_STATE;
253 
254 static int amd_iommu_enable_interrupts(void);
255 static int __init iommu_go_to_state(enum iommu_init_state state);
256 static void init_device_table_dma(void);
257 
258 static bool amd_iommu_pre_enabled = true;
259 
260 bool translation_pre_enabled(struct amd_iommu *iommu)
261 {
262 	return (iommu->flags & AMD_IOMMU_FLAG_TRANS_PRE_ENABLED);
263 }
264 EXPORT_SYMBOL(translation_pre_enabled);
265 
266 static void clear_translation_pre_enabled(struct amd_iommu *iommu)
267 {
268 	iommu->flags &= ~AMD_IOMMU_FLAG_TRANS_PRE_ENABLED;
269 }
270 
271 static void init_translation_status(struct amd_iommu *iommu)
272 {
273 	u64 ctrl;
274 
275 	ctrl = readq(iommu->mmio_base + MMIO_CONTROL_OFFSET);
276 	if (ctrl & (1<<CONTROL_IOMMU_EN))
277 		iommu->flags |= AMD_IOMMU_FLAG_TRANS_PRE_ENABLED;
278 }
279 
280 static inline void update_last_devid(u16 devid)
281 {
282 	if (devid > amd_iommu_last_bdf)
283 		amd_iommu_last_bdf = devid;
284 }
285 
286 static inline unsigned long tbl_size(int entry_size)
287 {
288 	unsigned shift = PAGE_SHIFT +
289 			 get_order(((int)amd_iommu_last_bdf + 1) * entry_size);
290 
291 	return 1UL << shift;
292 }
293 
294 int amd_iommu_get_num_iommus(void)
295 {
296 	return amd_iommus_present;
297 }
298 
299 /* Access to l1 and l2 indexed register spaces */
300 
301 static u32 iommu_read_l1(struct amd_iommu *iommu, u16 l1, u8 address)
302 {
303 	u32 val;
304 
305 	pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16));
306 	pci_read_config_dword(iommu->dev, 0xfc, &val);
307 	return val;
308 }
309 
310 static void iommu_write_l1(struct amd_iommu *iommu, u16 l1, u8 address, u32 val)
311 {
312 	pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16 | 1 << 31));
313 	pci_write_config_dword(iommu->dev, 0xfc, val);
314 	pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16));
315 }
316 
317 static u32 iommu_read_l2(struct amd_iommu *iommu, u8 address)
318 {
319 	u32 val;
320 
321 	pci_write_config_dword(iommu->dev, 0xf0, address);
322 	pci_read_config_dword(iommu->dev, 0xf4, &val);
323 	return val;
324 }
325 
326 static void iommu_write_l2(struct amd_iommu *iommu, u8 address, u32 val)
327 {
328 	pci_write_config_dword(iommu->dev, 0xf0, (address | 1 << 8));
329 	pci_write_config_dword(iommu->dev, 0xf4, val);
330 }
331 
332 /****************************************************************************
333  *
334  * AMD IOMMU MMIO register space handling functions
335  *
336  * These functions are used to program the IOMMU device registers in
337  * MMIO space required for that driver.
338  *
339  ****************************************************************************/
340 
341 /*
342  * This function set the exclusion range in the IOMMU. DMA accesses to the
343  * exclusion range are passed through untranslated
344  */
345 static void iommu_set_exclusion_range(struct amd_iommu *iommu)
346 {
347 	u64 start = iommu->exclusion_start & PAGE_MASK;
348 	u64 limit = (start + iommu->exclusion_length - 1) & PAGE_MASK;
349 	u64 entry;
350 
351 	if (!iommu->exclusion_start)
352 		return;
353 
354 	entry = start | MMIO_EXCL_ENABLE_MASK;
355 	memcpy_toio(iommu->mmio_base + MMIO_EXCL_BASE_OFFSET,
356 			&entry, sizeof(entry));
357 
358 	entry = limit;
359 	memcpy_toio(iommu->mmio_base + MMIO_EXCL_LIMIT_OFFSET,
360 			&entry, sizeof(entry));
361 }
362 
363 static void iommu_set_cwwb_range(struct amd_iommu *iommu)
364 {
365 	u64 start = iommu_virt_to_phys((void *)iommu->cmd_sem);
366 	u64 entry = start & PM_ADDR_MASK;
367 
368 	if (!iommu_feature(iommu, FEATURE_SNP))
369 		return;
370 
371 	/* Note:
372 	 * Re-purpose Exclusion base/limit registers for Completion wait
373 	 * write-back base/limit.
374 	 */
375 	memcpy_toio(iommu->mmio_base + MMIO_EXCL_BASE_OFFSET,
376 		    &entry, sizeof(entry));
377 
378 	/* Note:
379 	 * Default to 4 Kbytes, which can be specified by setting base
380 	 * address equal to the limit address.
381 	 */
382 	memcpy_toio(iommu->mmio_base + MMIO_EXCL_LIMIT_OFFSET,
383 		    &entry, sizeof(entry));
384 }
385 
386 /* Programs the physical address of the device table into the IOMMU hardware */
387 static void iommu_set_device_table(struct amd_iommu *iommu)
388 {
389 	u64 entry;
390 
391 	BUG_ON(iommu->mmio_base == NULL);
392 
393 	entry = iommu_virt_to_phys(amd_iommu_dev_table);
394 	entry |= (dev_table_size >> 12) - 1;
395 	memcpy_toio(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET,
396 			&entry, sizeof(entry));
397 }
398 
399 /* Generic functions to enable/disable certain features of the IOMMU. */
400 static void iommu_feature_enable(struct amd_iommu *iommu, u8 bit)
401 {
402 	u64 ctrl;
403 
404 	ctrl = readq(iommu->mmio_base +  MMIO_CONTROL_OFFSET);
405 	ctrl |= (1ULL << bit);
406 	writeq(ctrl, iommu->mmio_base +  MMIO_CONTROL_OFFSET);
407 }
408 
409 static void iommu_feature_disable(struct amd_iommu *iommu, u8 bit)
410 {
411 	u64 ctrl;
412 
413 	ctrl = readq(iommu->mmio_base + MMIO_CONTROL_OFFSET);
414 	ctrl &= ~(1ULL << bit);
415 	writeq(ctrl, iommu->mmio_base + MMIO_CONTROL_OFFSET);
416 }
417 
418 static void iommu_set_inv_tlb_timeout(struct amd_iommu *iommu, int timeout)
419 {
420 	u64 ctrl;
421 
422 	ctrl = readq(iommu->mmio_base + MMIO_CONTROL_OFFSET);
423 	ctrl &= ~CTRL_INV_TO_MASK;
424 	ctrl |= (timeout << CONTROL_INV_TIMEOUT) & CTRL_INV_TO_MASK;
425 	writeq(ctrl, iommu->mmio_base + MMIO_CONTROL_OFFSET);
426 }
427 
428 /* Function to enable the hardware */
429 static void iommu_enable(struct amd_iommu *iommu)
430 {
431 	iommu_feature_enable(iommu, CONTROL_IOMMU_EN);
432 }
433 
434 static void iommu_disable(struct amd_iommu *iommu)
435 {
436 	if (!iommu->mmio_base)
437 		return;
438 
439 	/* Disable command buffer */
440 	iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
441 
442 	/* Disable event logging and event interrupts */
443 	iommu_feature_disable(iommu, CONTROL_EVT_INT_EN);
444 	iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN);
445 
446 	/* Disable IOMMU GA_LOG */
447 	iommu_feature_disable(iommu, CONTROL_GALOG_EN);
448 	iommu_feature_disable(iommu, CONTROL_GAINT_EN);
449 
450 	/* Disable IOMMU hardware itself */
451 	iommu_feature_disable(iommu, CONTROL_IOMMU_EN);
452 }
453 
454 /*
455  * mapping and unmapping functions for the IOMMU MMIO space. Each AMD IOMMU in
456  * the system has one.
457  */
458 static u8 __iomem * __init iommu_map_mmio_space(u64 address, u64 end)
459 {
460 	if (!request_mem_region(address, end, "amd_iommu")) {
461 		pr_err("Can not reserve memory region %llx-%llx for mmio\n",
462 			address, end);
463 		pr_err("This is a BIOS bug. Please contact your hardware vendor\n");
464 		return NULL;
465 	}
466 
467 	return (u8 __iomem *)ioremap(address, end);
468 }
469 
470 static void __init iommu_unmap_mmio_space(struct amd_iommu *iommu)
471 {
472 	if (iommu->mmio_base)
473 		iounmap(iommu->mmio_base);
474 	release_mem_region(iommu->mmio_phys, iommu->mmio_phys_end);
475 }
476 
477 static inline u32 get_ivhd_header_size(struct ivhd_header *h)
478 {
479 	u32 size = 0;
480 
481 	switch (h->type) {
482 	case 0x10:
483 		size = 24;
484 		break;
485 	case 0x11:
486 	case 0x40:
487 		size = 40;
488 		break;
489 	}
490 	return size;
491 }
492 
493 /****************************************************************************
494  *
495  * The functions below belong to the first pass of AMD IOMMU ACPI table
496  * parsing. In this pass we try to find out the highest device id this
497  * code has to handle. Upon this information the size of the shared data
498  * structures is determined later.
499  *
500  ****************************************************************************/
501 
502 /*
503  * This function calculates the length of a given IVHD entry
504  */
505 static inline int ivhd_entry_length(u8 *ivhd)
506 {
507 	u32 type = ((struct ivhd_entry *)ivhd)->type;
508 
509 	if (type < 0x80) {
510 		return 0x04 << (*ivhd >> 6);
511 	} else if (type == IVHD_DEV_ACPI_HID) {
512 		/* For ACPI_HID, offset 21 is uid len */
513 		return *((u8 *)ivhd + 21) + 22;
514 	}
515 	return 0;
516 }
517 
518 /*
519  * After reading the highest device id from the IOMMU PCI capability header
520  * this function looks if there is a higher device id defined in the ACPI table
521  */
522 static int __init find_last_devid_from_ivhd(struct ivhd_header *h)
523 {
524 	u8 *p = (void *)h, *end = (void *)h;
525 	struct ivhd_entry *dev;
526 
527 	u32 ivhd_size = get_ivhd_header_size(h);
528 
529 	if (!ivhd_size) {
530 		pr_err("Unsupported IVHD type %#x\n", h->type);
531 		return -EINVAL;
532 	}
533 
534 	p += ivhd_size;
535 	end += h->length;
536 
537 	while (p < end) {
538 		dev = (struct ivhd_entry *)p;
539 		switch (dev->type) {
540 		case IVHD_DEV_ALL:
541 			/* Use maximum BDF value for DEV_ALL */
542 			update_last_devid(0xffff);
543 			break;
544 		case IVHD_DEV_SELECT:
545 		case IVHD_DEV_RANGE_END:
546 		case IVHD_DEV_ALIAS:
547 		case IVHD_DEV_EXT_SELECT:
548 			/* all the above subfield types refer to device ids */
549 			update_last_devid(dev->devid);
550 			break;
551 		default:
552 			break;
553 		}
554 		p += ivhd_entry_length(p);
555 	}
556 
557 	WARN_ON(p != end);
558 
559 	return 0;
560 }
561 
562 static int __init check_ivrs_checksum(struct acpi_table_header *table)
563 {
564 	int i;
565 	u8 checksum = 0, *p = (u8 *)table;
566 
567 	for (i = 0; i < table->length; ++i)
568 		checksum += p[i];
569 	if (checksum != 0) {
570 		/* ACPI table corrupt */
571 		pr_err(FW_BUG "IVRS invalid checksum\n");
572 		return -ENODEV;
573 	}
574 
575 	return 0;
576 }
577 
578 /*
579  * Iterate over all IVHD entries in the ACPI table and find the highest device
580  * id which we need to handle. This is the first of three functions which parse
581  * the ACPI table. So we check the checksum here.
582  */
583 static int __init find_last_devid_acpi(struct acpi_table_header *table)
584 {
585 	u8 *p = (u8 *)table, *end = (u8 *)table;
586 	struct ivhd_header *h;
587 
588 	p += IVRS_HEADER_LENGTH;
589 
590 	end += table->length;
591 	while (p < end) {
592 		h = (struct ivhd_header *)p;
593 		if (h->type == amd_iommu_target_ivhd_type) {
594 			int ret = find_last_devid_from_ivhd(h);
595 
596 			if (ret)
597 				return ret;
598 		}
599 		p += h->length;
600 	}
601 	WARN_ON(p != end);
602 
603 	return 0;
604 }
605 
606 /****************************************************************************
607  *
608  * The following functions belong to the code path which parses the ACPI table
609  * the second time. In this ACPI parsing iteration we allocate IOMMU specific
610  * data structures, initialize the device/alias/rlookup table and also
611  * basically initialize the hardware.
612  *
613  ****************************************************************************/
614 
615 /*
616  * Allocates the command buffer. This buffer is per AMD IOMMU. We can
617  * write commands to that buffer later and the IOMMU will execute them
618  * asynchronously
619  */
620 static int __init alloc_command_buffer(struct amd_iommu *iommu)
621 {
622 	iommu->cmd_buf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
623 						  get_order(CMD_BUFFER_SIZE));
624 
625 	return iommu->cmd_buf ? 0 : -ENOMEM;
626 }
627 
628 /*
629  * This function resets the command buffer if the IOMMU stopped fetching
630  * commands from it.
631  */
632 void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu)
633 {
634 	iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
635 
636 	writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
637 	writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
638 	iommu->cmd_buf_head = 0;
639 	iommu->cmd_buf_tail = 0;
640 
641 	iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
642 }
643 
644 /*
645  * This function writes the command buffer address to the hardware and
646  * enables it.
647  */
648 static void iommu_enable_command_buffer(struct amd_iommu *iommu)
649 {
650 	u64 entry;
651 
652 	BUG_ON(iommu->cmd_buf == NULL);
653 
654 	entry = iommu_virt_to_phys(iommu->cmd_buf);
655 	entry |= MMIO_CMD_SIZE_512;
656 
657 	memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET,
658 		    &entry, sizeof(entry));
659 
660 	amd_iommu_reset_cmd_buffer(iommu);
661 }
662 
663 /*
664  * This function disables the command buffer
665  */
666 static void iommu_disable_command_buffer(struct amd_iommu *iommu)
667 {
668 	iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
669 }
670 
671 static void __init free_command_buffer(struct amd_iommu *iommu)
672 {
673 	free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE));
674 }
675 
676 static void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu,
677 					 gfp_t gfp, size_t size)
678 {
679 	int order = get_order(size);
680 	void *buf = (void *)__get_free_pages(gfp, order);
681 
682 	if (buf &&
683 	    iommu_feature(iommu, FEATURE_SNP) &&
684 	    set_memory_4k((unsigned long)buf, (1 << order))) {
685 		free_pages((unsigned long)buf, order);
686 		buf = NULL;
687 	}
688 
689 	return buf;
690 }
691 
692 /* allocates the memory where the IOMMU will log its events to */
693 static int __init alloc_event_buffer(struct amd_iommu *iommu)
694 {
695 	iommu->evt_buf = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO,
696 					      EVT_BUFFER_SIZE);
697 
698 	return iommu->evt_buf ? 0 : -ENOMEM;
699 }
700 
701 static void iommu_enable_event_buffer(struct amd_iommu *iommu)
702 {
703 	u64 entry;
704 
705 	BUG_ON(iommu->evt_buf == NULL);
706 
707 	entry = iommu_virt_to_phys(iommu->evt_buf) | EVT_LEN_MASK;
708 
709 	memcpy_toio(iommu->mmio_base + MMIO_EVT_BUF_OFFSET,
710 		    &entry, sizeof(entry));
711 
712 	/* set head and tail to zero manually */
713 	writel(0x00, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
714 	writel(0x00, iommu->mmio_base + MMIO_EVT_TAIL_OFFSET);
715 
716 	iommu_feature_enable(iommu, CONTROL_EVT_LOG_EN);
717 }
718 
719 /*
720  * This function disables the event log buffer
721  */
722 static void iommu_disable_event_buffer(struct amd_iommu *iommu)
723 {
724 	iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN);
725 }
726 
727 static void __init free_event_buffer(struct amd_iommu *iommu)
728 {
729 	free_pages((unsigned long)iommu->evt_buf, get_order(EVT_BUFFER_SIZE));
730 }
731 
732 /* allocates the memory where the IOMMU will log its events to */
733 static int __init alloc_ppr_log(struct amd_iommu *iommu)
734 {
735 	iommu->ppr_log = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO,
736 					      PPR_LOG_SIZE);
737 
738 	return iommu->ppr_log ? 0 : -ENOMEM;
739 }
740 
741 static void iommu_enable_ppr_log(struct amd_iommu *iommu)
742 {
743 	u64 entry;
744 
745 	if (iommu->ppr_log == NULL)
746 		return;
747 
748 	entry = iommu_virt_to_phys(iommu->ppr_log) | PPR_LOG_SIZE_512;
749 
750 	memcpy_toio(iommu->mmio_base + MMIO_PPR_LOG_OFFSET,
751 		    &entry, sizeof(entry));
752 
753 	/* set head and tail to zero manually */
754 	writel(0x00, iommu->mmio_base + MMIO_PPR_HEAD_OFFSET);
755 	writel(0x00, iommu->mmio_base + MMIO_PPR_TAIL_OFFSET);
756 
757 	iommu_feature_enable(iommu, CONTROL_PPRLOG_EN);
758 	iommu_feature_enable(iommu, CONTROL_PPR_EN);
759 }
760 
761 static void __init free_ppr_log(struct amd_iommu *iommu)
762 {
763 	free_pages((unsigned long)iommu->ppr_log, get_order(PPR_LOG_SIZE));
764 }
765 
766 static void free_ga_log(struct amd_iommu *iommu)
767 {
768 #ifdef CONFIG_IRQ_REMAP
769 	free_pages((unsigned long)iommu->ga_log, get_order(GA_LOG_SIZE));
770 	free_pages((unsigned long)iommu->ga_log_tail, get_order(8));
771 #endif
772 }
773 
774 static int iommu_ga_log_enable(struct amd_iommu *iommu)
775 {
776 #ifdef CONFIG_IRQ_REMAP
777 	u32 status, i;
778 
779 	if (!iommu->ga_log)
780 		return -EINVAL;
781 
782 	status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
783 
784 	/* Check if already running */
785 	if (status & (MMIO_STATUS_GALOG_RUN_MASK))
786 		return 0;
787 
788 	iommu_feature_enable(iommu, CONTROL_GAINT_EN);
789 	iommu_feature_enable(iommu, CONTROL_GALOG_EN);
790 
791 	for (i = 0; i < LOOP_TIMEOUT; ++i) {
792 		status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
793 		if (status & (MMIO_STATUS_GALOG_RUN_MASK))
794 			break;
795 	}
796 
797 	if (i >= LOOP_TIMEOUT)
798 		return -EINVAL;
799 #endif /* CONFIG_IRQ_REMAP */
800 	return 0;
801 }
802 
803 #ifdef CONFIG_IRQ_REMAP
804 static int iommu_init_ga_log(struct amd_iommu *iommu)
805 {
806 	u64 entry;
807 
808 	if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
809 		return 0;
810 
811 	iommu->ga_log = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
812 					get_order(GA_LOG_SIZE));
813 	if (!iommu->ga_log)
814 		goto err_out;
815 
816 	iommu->ga_log_tail = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
817 					get_order(8));
818 	if (!iommu->ga_log_tail)
819 		goto err_out;
820 
821 	entry = iommu_virt_to_phys(iommu->ga_log) | GA_LOG_SIZE_512;
822 	memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_BASE_OFFSET,
823 		    &entry, sizeof(entry));
824 	entry = (iommu_virt_to_phys(iommu->ga_log_tail) &
825 		 (BIT_ULL(52)-1)) & ~7ULL;
826 	memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_TAIL_OFFSET,
827 		    &entry, sizeof(entry));
828 	writel(0x00, iommu->mmio_base + MMIO_GA_HEAD_OFFSET);
829 	writel(0x00, iommu->mmio_base + MMIO_GA_TAIL_OFFSET);
830 
831 	return 0;
832 err_out:
833 	free_ga_log(iommu);
834 	return -EINVAL;
835 }
836 #endif /* CONFIG_IRQ_REMAP */
837 
838 static int iommu_init_ga(struct amd_iommu *iommu)
839 {
840 	int ret = 0;
841 
842 #ifdef CONFIG_IRQ_REMAP
843 	/* Note: We have already checked GASup from IVRS table.
844 	 *       Now, we need to make sure that GAMSup is set.
845 	 */
846 	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) &&
847 	    !iommu_feature(iommu, FEATURE_GAM_VAPIC))
848 		amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
849 
850 	ret = iommu_init_ga_log(iommu);
851 #endif /* CONFIG_IRQ_REMAP */
852 
853 	return ret;
854 }
855 
856 static int __init alloc_cwwb_sem(struct amd_iommu *iommu)
857 {
858 	iommu->cmd_sem = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, 1);
859 
860 	return iommu->cmd_sem ? 0 : -ENOMEM;
861 }
862 
863 static void __init free_cwwb_sem(struct amd_iommu *iommu)
864 {
865 	if (iommu->cmd_sem)
866 		free_page((unsigned long)iommu->cmd_sem);
867 }
868 
869 static void iommu_enable_xt(struct amd_iommu *iommu)
870 {
871 #ifdef CONFIG_IRQ_REMAP
872 	/*
873 	 * XT mode (32-bit APIC destination ID) requires
874 	 * GA mode (128-bit IRTE support) as a prerequisite.
875 	 */
876 	if (AMD_IOMMU_GUEST_IR_GA(amd_iommu_guest_ir) &&
877 	    amd_iommu_xt_mode == IRQ_REMAP_X2APIC_MODE)
878 		iommu_feature_enable(iommu, CONTROL_XT_EN);
879 #endif /* CONFIG_IRQ_REMAP */
880 }
881 
882 static void iommu_enable_gt(struct amd_iommu *iommu)
883 {
884 	if (!iommu_feature(iommu, FEATURE_GT))
885 		return;
886 
887 	iommu_feature_enable(iommu, CONTROL_GT_EN);
888 }
889 
890 /* sets a specific bit in the device table entry. */
891 static void set_dev_entry_bit(u16 devid, u8 bit)
892 {
893 	int i = (bit >> 6) & 0x03;
894 	int _bit = bit & 0x3f;
895 
896 	amd_iommu_dev_table[devid].data[i] |= (1UL << _bit);
897 }
898 
899 static int get_dev_entry_bit(u16 devid, u8 bit)
900 {
901 	int i = (bit >> 6) & 0x03;
902 	int _bit = bit & 0x3f;
903 
904 	return (amd_iommu_dev_table[devid].data[i] & (1UL << _bit)) >> _bit;
905 }
906 
907 
908 static bool copy_device_table(void)
909 {
910 	u64 int_ctl, int_tab_len, entry = 0, last_entry = 0;
911 	struct dev_table_entry *old_devtb = NULL;
912 	u32 lo, hi, devid, old_devtb_size;
913 	phys_addr_t old_devtb_phys;
914 	struct amd_iommu *iommu;
915 	u16 dom_id, dte_v, irq_v;
916 	gfp_t gfp_flag;
917 	u64 tmp;
918 
919 	if (!amd_iommu_pre_enabled)
920 		return false;
921 
922 	pr_warn("Translation is already enabled - trying to copy translation structures\n");
923 	for_each_iommu(iommu) {
924 		/* All IOMMUs should use the same device table with the same size */
925 		lo = readl(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET);
926 		hi = readl(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET + 4);
927 		entry = (((u64) hi) << 32) + lo;
928 		if (last_entry && last_entry != entry) {
929 			pr_err("IOMMU:%d should use the same dev table as others!\n",
930 				iommu->index);
931 			return false;
932 		}
933 		last_entry = entry;
934 
935 		old_devtb_size = ((entry & ~PAGE_MASK) + 1) << 12;
936 		if (old_devtb_size != dev_table_size) {
937 			pr_err("The device table size of IOMMU:%d is not expected!\n",
938 				iommu->index);
939 			return false;
940 		}
941 	}
942 
943 	/*
944 	 * When SME is enabled in the first kernel, the entry includes the
945 	 * memory encryption mask(sme_me_mask), we must remove the memory
946 	 * encryption mask to obtain the true physical address in kdump kernel.
947 	 */
948 	old_devtb_phys = __sme_clr(entry) & PAGE_MASK;
949 
950 	if (old_devtb_phys >= 0x100000000ULL) {
951 		pr_err("The address of old device table is above 4G, not trustworthy!\n");
952 		return false;
953 	}
954 	old_devtb = (sme_active() && is_kdump_kernel())
955 		    ? (__force void *)ioremap_encrypted(old_devtb_phys,
956 							dev_table_size)
957 		    : memremap(old_devtb_phys, dev_table_size, MEMREMAP_WB);
958 
959 	if (!old_devtb)
960 		return false;
961 
962 	gfp_flag = GFP_KERNEL | __GFP_ZERO | GFP_DMA32;
963 	old_dev_tbl_cpy = (void *)__get_free_pages(gfp_flag,
964 				get_order(dev_table_size));
965 	if (old_dev_tbl_cpy == NULL) {
966 		pr_err("Failed to allocate memory for copying old device table!\n");
967 		return false;
968 	}
969 
970 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) {
971 		old_dev_tbl_cpy[devid] = old_devtb[devid];
972 		dom_id = old_devtb[devid].data[1] & DEV_DOMID_MASK;
973 		dte_v = old_devtb[devid].data[0] & DTE_FLAG_V;
974 
975 		if (dte_v && dom_id) {
976 			old_dev_tbl_cpy[devid].data[0] = old_devtb[devid].data[0];
977 			old_dev_tbl_cpy[devid].data[1] = old_devtb[devid].data[1];
978 			__set_bit(dom_id, amd_iommu_pd_alloc_bitmap);
979 			/* If gcr3 table existed, mask it out */
980 			if (old_devtb[devid].data[0] & DTE_FLAG_GV) {
981 				tmp = DTE_GCR3_VAL_B(~0ULL) << DTE_GCR3_SHIFT_B;
982 				tmp |= DTE_GCR3_VAL_C(~0ULL) << DTE_GCR3_SHIFT_C;
983 				old_dev_tbl_cpy[devid].data[1] &= ~tmp;
984 				tmp = DTE_GCR3_VAL_A(~0ULL) << DTE_GCR3_SHIFT_A;
985 				tmp |= DTE_FLAG_GV;
986 				old_dev_tbl_cpy[devid].data[0] &= ~tmp;
987 			}
988 		}
989 
990 		irq_v = old_devtb[devid].data[2] & DTE_IRQ_REMAP_ENABLE;
991 		int_ctl = old_devtb[devid].data[2] & DTE_IRQ_REMAP_INTCTL_MASK;
992 		int_tab_len = old_devtb[devid].data[2] & DTE_IRQ_TABLE_LEN_MASK;
993 		if (irq_v && (int_ctl || int_tab_len)) {
994 			if ((int_ctl != DTE_IRQ_REMAP_INTCTL) ||
995 			    (int_tab_len != DTE_IRQ_TABLE_LEN)) {
996 				pr_err("Wrong old irq remapping flag: %#x\n", devid);
997 				return false;
998 			}
999 
1000 		        old_dev_tbl_cpy[devid].data[2] = old_devtb[devid].data[2];
1001 		}
1002 	}
1003 	memunmap(old_devtb);
1004 
1005 	return true;
1006 }
1007 
1008 void amd_iommu_apply_erratum_63(u16 devid)
1009 {
1010 	int sysmgt;
1011 
1012 	sysmgt = get_dev_entry_bit(devid, DEV_ENTRY_SYSMGT1) |
1013 		 (get_dev_entry_bit(devid, DEV_ENTRY_SYSMGT2) << 1);
1014 
1015 	if (sysmgt == 0x01)
1016 		set_dev_entry_bit(devid, DEV_ENTRY_IW);
1017 }
1018 
1019 /* Writes the specific IOMMU for a device into the rlookup table */
1020 static void __init set_iommu_for_device(struct amd_iommu *iommu, u16 devid)
1021 {
1022 	amd_iommu_rlookup_table[devid] = iommu;
1023 }
1024 
1025 /*
1026  * This function takes the device specific flags read from the ACPI
1027  * table and sets up the device table entry with that information
1028  */
1029 static void __init set_dev_entry_from_acpi(struct amd_iommu *iommu,
1030 					   u16 devid, u32 flags, u32 ext_flags)
1031 {
1032 	if (flags & ACPI_DEVFLAG_INITPASS)
1033 		set_dev_entry_bit(devid, DEV_ENTRY_INIT_PASS);
1034 	if (flags & ACPI_DEVFLAG_EXTINT)
1035 		set_dev_entry_bit(devid, DEV_ENTRY_EINT_PASS);
1036 	if (flags & ACPI_DEVFLAG_NMI)
1037 		set_dev_entry_bit(devid, DEV_ENTRY_NMI_PASS);
1038 	if (flags & ACPI_DEVFLAG_SYSMGT1)
1039 		set_dev_entry_bit(devid, DEV_ENTRY_SYSMGT1);
1040 	if (flags & ACPI_DEVFLAG_SYSMGT2)
1041 		set_dev_entry_bit(devid, DEV_ENTRY_SYSMGT2);
1042 	if (flags & ACPI_DEVFLAG_LINT0)
1043 		set_dev_entry_bit(devid, DEV_ENTRY_LINT0_PASS);
1044 	if (flags & ACPI_DEVFLAG_LINT1)
1045 		set_dev_entry_bit(devid, DEV_ENTRY_LINT1_PASS);
1046 
1047 	amd_iommu_apply_erratum_63(devid);
1048 
1049 	set_iommu_for_device(iommu, devid);
1050 }
1051 
1052 int __init add_special_device(u8 type, u8 id, u16 *devid, bool cmd_line)
1053 {
1054 	struct devid_map *entry;
1055 	struct list_head *list;
1056 
1057 	if (type == IVHD_SPECIAL_IOAPIC)
1058 		list = &ioapic_map;
1059 	else if (type == IVHD_SPECIAL_HPET)
1060 		list = &hpet_map;
1061 	else
1062 		return -EINVAL;
1063 
1064 	list_for_each_entry(entry, list, list) {
1065 		if (!(entry->id == id && entry->cmd_line))
1066 			continue;
1067 
1068 		pr_info("Command-line override present for %s id %d - ignoring\n",
1069 			type == IVHD_SPECIAL_IOAPIC ? "IOAPIC" : "HPET", id);
1070 
1071 		*devid = entry->devid;
1072 
1073 		return 0;
1074 	}
1075 
1076 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1077 	if (!entry)
1078 		return -ENOMEM;
1079 
1080 	entry->id	= id;
1081 	entry->devid	= *devid;
1082 	entry->cmd_line	= cmd_line;
1083 
1084 	list_add_tail(&entry->list, list);
1085 
1086 	return 0;
1087 }
1088 
1089 static int __init add_acpi_hid_device(u8 *hid, u8 *uid, u16 *devid,
1090 				      bool cmd_line)
1091 {
1092 	struct acpihid_map_entry *entry;
1093 	struct list_head *list = &acpihid_map;
1094 
1095 	list_for_each_entry(entry, list, list) {
1096 		if (strcmp(entry->hid, hid) ||
1097 		    (*uid && *entry->uid && strcmp(entry->uid, uid)) ||
1098 		    !entry->cmd_line)
1099 			continue;
1100 
1101 		pr_info("Command-line override for hid:%s uid:%s\n",
1102 			hid, uid);
1103 		*devid = entry->devid;
1104 		return 0;
1105 	}
1106 
1107 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1108 	if (!entry)
1109 		return -ENOMEM;
1110 
1111 	memcpy(entry->uid, uid, strlen(uid));
1112 	memcpy(entry->hid, hid, strlen(hid));
1113 	entry->devid = *devid;
1114 	entry->cmd_line	= cmd_line;
1115 	entry->root_devid = (entry->devid & (~0x7));
1116 
1117 	pr_info("%s, add hid:%s, uid:%s, rdevid:%d\n",
1118 		entry->cmd_line ? "cmd" : "ivrs",
1119 		entry->hid, entry->uid, entry->root_devid);
1120 
1121 	list_add_tail(&entry->list, list);
1122 	return 0;
1123 }
1124 
1125 static int __init add_early_maps(void)
1126 {
1127 	int i, ret;
1128 
1129 	for (i = 0; i < early_ioapic_map_size; ++i) {
1130 		ret = add_special_device(IVHD_SPECIAL_IOAPIC,
1131 					 early_ioapic_map[i].id,
1132 					 &early_ioapic_map[i].devid,
1133 					 early_ioapic_map[i].cmd_line);
1134 		if (ret)
1135 			return ret;
1136 	}
1137 
1138 	for (i = 0; i < early_hpet_map_size; ++i) {
1139 		ret = add_special_device(IVHD_SPECIAL_HPET,
1140 					 early_hpet_map[i].id,
1141 					 &early_hpet_map[i].devid,
1142 					 early_hpet_map[i].cmd_line);
1143 		if (ret)
1144 			return ret;
1145 	}
1146 
1147 	for (i = 0; i < early_acpihid_map_size; ++i) {
1148 		ret = add_acpi_hid_device(early_acpihid_map[i].hid,
1149 					  early_acpihid_map[i].uid,
1150 					  &early_acpihid_map[i].devid,
1151 					  early_acpihid_map[i].cmd_line);
1152 		if (ret)
1153 			return ret;
1154 	}
1155 
1156 	return 0;
1157 }
1158 
1159 /*
1160  * Takes a pointer to an AMD IOMMU entry in the ACPI table and
1161  * initializes the hardware and our data structures with it.
1162  */
1163 static int __init init_iommu_from_acpi(struct amd_iommu *iommu,
1164 					struct ivhd_header *h)
1165 {
1166 	u8 *p = (u8 *)h;
1167 	u8 *end = p, flags = 0;
1168 	u16 devid = 0, devid_start = 0, devid_to = 0;
1169 	u32 dev_i, ext_flags = 0;
1170 	bool alias = false;
1171 	struct ivhd_entry *e;
1172 	u32 ivhd_size;
1173 	int ret;
1174 
1175 
1176 	ret = add_early_maps();
1177 	if (ret)
1178 		return ret;
1179 
1180 	amd_iommu_apply_ivrs_quirks();
1181 
1182 	/*
1183 	 * First save the recommended feature enable bits from ACPI
1184 	 */
1185 	iommu->acpi_flags = h->flags;
1186 
1187 	/*
1188 	 * Done. Now parse the device entries
1189 	 */
1190 	ivhd_size = get_ivhd_header_size(h);
1191 	if (!ivhd_size) {
1192 		pr_err("Unsupported IVHD type %#x\n", h->type);
1193 		return -EINVAL;
1194 	}
1195 
1196 	p += ivhd_size;
1197 
1198 	end += h->length;
1199 
1200 
1201 	while (p < end) {
1202 		e = (struct ivhd_entry *)p;
1203 		switch (e->type) {
1204 		case IVHD_DEV_ALL:
1205 
1206 			DUMP_printk("  DEV_ALL\t\t\tflags: %02x\n", e->flags);
1207 
1208 			for (dev_i = 0; dev_i <= amd_iommu_last_bdf; ++dev_i)
1209 				set_dev_entry_from_acpi(iommu, dev_i, e->flags, 0);
1210 			break;
1211 		case IVHD_DEV_SELECT:
1212 
1213 			DUMP_printk("  DEV_SELECT\t\t\t devid: %02x:%02x.%x "
1214 				    "flags: %02x\n",
1215 				    PCI_BUS_NUM(e->devid),
1216 				    PCI_SLOT(e->devid),
1217 				    PCI_FUNC(e->devid),
1218 				    e->flags);
1219 
1220 			devid = e->devid;
1221 			set_dev_entry_from_acpi(iommu, devid, e->flags, 0);
1222 			break;
1223 		case IVHD_DEV_SELECT_RANGE_START:
1224 
1225 			DUMP_printk("  DEV_SELECT_RANGE_START\t "
1226 				    "devid: %02x:%02x.%x flags: %02x\n",
1227 				    PCI_BUS_NUM(e->devid),
1228 				    PCI_SLOT(e->devid),
1229 				    PCI_FUNC(e->devid),
1230 				    e->flags);
1231 
1232 			devid_start = e->devid;
1233 			flags = e->flags;
1234 			ext_flags = 0;
1235 			alias = false;
1236 			break;
1237 		case IVHD_DEV_ALIAS:
1238 
1239 			DUMP_printk("  DEV_ALIAS\t\t\t devid: %02x:%02x.%x "
1240 				    "flags: %02x devid_to: %02x:%02x.%x\n",
1241 				    PCI_BUS_NUM(e->devid),
1242 				    PCI_SLOT(e->devid),
1243 				    PCI_FUNC(e->devid),
1244 				    e->flags,
1245 				    PCI_BUS_NUM(e->ext >> 8),
1246 				    PCI_SLOT(e->ext >> 8),
1247 				    PCI_FUNC(e->ext >> 8));
1248 
1249 			devid = e->devid;
1250 			devid_to = e->ext >> 8;
1251 			set_dev_entry_from_acpi(iommu, devid   , e->flags, 0);
1252 			set_dev_entry_from_acpi(iommu, devid_to, e->flags, 0);
1253 			amd_iommu_alias_table[devid] = devid_to;
1254 			break;
1255 		case IVHD_DEV_ALIAS_RANGE:
1256 
1257 			DUMP_printk("  DEV_ALIAS_RANGE\t\t "
1258 				    "devid: %02x:%02x.%x flags: %02x "
1259 				    "devid_to: %02x:%02x.%x\n",
1260 				    PCI_BUS_NUM(e->devid),
1261 				    PCI_SLOT(e->devid),
1262 				    PCI_FUNC(e->devid),
1263 				    e->flags,
1264 				    PCI_BUS_NUM(e->ext >> 8),
1265 				    PCI_SLOT(e->ext >> 8),
1266 				    PCI_FUNC(e->ext >> 8));
1267 
1268 			devid_start = e->devid;
1269 			flags = e->flags;
1270 			devid_to = e->ext >> 8;
1271 			ext_flags = 0;
1272 			alias = true;
1273 			break;
1274 		case IVHD_DEV_EXT_SELECT:
1275 
1276 			DUMP_printk("  DEV_EXT_SELECT\t\t devid: %02x:%02x.%x "
1277 				    "flags: %02x ext: %08x\n",
1278 				    PCI_BUS_NUM(e->devid),
1279 				    PCI_SLOT(e->devid),
1280 				    PCI_FUNC(e->devid),
1281 				    e->flags, e->ext);
1282 
1283 			devid = e->devid;
1284 			set_dev_entry_from_acpi(iommu, devid, e->flags,
1285 						e->ext);
1286 			break;
1287 		case IVHD_DEV_EXT_SELECT_RANGE:
1288 
1289 			DUMP_printk("  DEV_EXT_SELECT_RANGE\t devid: "
1290 				    "%02x:%02x.%x flags: %02x ext: %08x\n",
1291 				    PCI_BUS_NUM(e->devid),
1292 				    PCI_SLOT(e->devid),
1293 				    PCI_FUNC(e->devid),
1294 				    e->flags, e->ext);
1295 
1296 			devid_start = e->devid;
1297 			flags = e->flags;
1298 			ext_flags = e->ext;
1299 			alias = false;
1300 			break;
1301 		case IVHD_DEV_RANGE_END:
1302 
1303 			DUMP_printk("  DEV_RANGE_END\t\t devid: %02x:%02x.%x\n",
1304 				    PCI_BUS_NUM(e->devid),
1305 				    PCI_SLOT(e->devid),
1306 				    PCI_FUNC(e->devid));
1307 
1308 			devid = e->devid;
1309 			for (dev_i = devid_start; dev_i <= devid; ++dev_i) {
1310 				if (alias) {
1311 					amd_iommu_alias_table[dev_i] = devid_to;
1312 					set_dev_entry_from_acpi(iommu,
1313 						devid_to, flags, ext_flags);
1314 				}
1315 				set_dev_entry_from_acpi(iommu, dev_i,
1316 							flags, ext_flags);
1317 			}
1318 			break;
1319 		case IVHD_DEV_SPECIAL: {
1320 			u8 handle, type;
1321 			const char *var;
1322 			u16 devid;
1323 			int ret;
1324 
1325 			handle = e->ext & 0xff;
1326 			devid  = (e->ext >>  8) & 0xffff;
1327 			type   = (e->ext >> 24) & 0xff;
1328 
1329 			if (type == IVHD_SPECIAL_IOAPIC)
1330 				var = "IOAPIC";
1331 			else if (type == IVHD_SPECIAL_HPET)
1332 				var = "HPET";
1333 			else
1334 				var = "UNKNOWN";
1335 
1336 			DUMP_printk("  DEV_SPECIAL(%s[%d])\t\tdevid: %02x:%02x.%x\n",
1337 				    var, (int)handle,
1338 				    PCI_BUS_NUM(devid),
1339 				    PCI_SLOT(devid),
1340 				    PCI_FUNC(devid));
1341 
1342 			ret = add_special_device(type, handle, &devid, false);
1343 			if (ret)
1344 				return ret;
1345 
1346 			/*
1347 			 * add_special_device might update the devid in case a
1348 			 * command-line override is present. So call
1349 			 * set_dev_entry_from_acpi after add_special_device.
1350 			 */
1351 			set_dev_entry_from_acpi(iommu, devid, e->flags, 0);
1352 
1353 			break;
1354 		}
1355 		case IVHD_DEV_ACPI_HID: {
1356 			u16 devid;
1357 			u8 hid[ACPIHID_HID_LEN];
1358 			u8 uid[ACPIHID_UID_LEN];
1359 			int ret;
1360 
1361 			if (h->type != 0x40) {
1362 				pr_err(FW_BUG "Invalid IVHD device type %#x\n",
1363 				       e->type);
1364 				break;
1365 			}
1366 
1367 			memcpy(hid, (u8 *)(&e->ext), ACPIHID_HID_LEN - 1);
1368 			hid[ACPIHID_HID_LEN - 1] = '\0';
1369 
1370 			if (!(*hid)) {
1371 				pr_err(FW_BUG "Invalid HID.\n");
1372 				break;
1373 			}
1374 
1375 			uid[0] = '\0';
1376 			switch (e->uidf) {
1377 			case UID_NOT_PRESENT:
1378 
1379 				if (e->uidl != 0)
1380 					pr_warn(FW_BUG "Invalid UID length.\n");
1381 
1382 				break;
1383 			case UID_IS_INTEGER:
1384 
1385 				sprintf(uid, "%d", e->uid);
1386 
1387 				break;
1388 			case UID_IS_CHARACTER:
1389 
1390 				memcpy(uid, &e->uid, e->uidl);
1391 				uid[e->uidl] = '\0';
1392 
1393 				break;
1394 			default:
1395 				break;
1396 			}
1397 
1398 			devid = e->devid;
1399 			DUMP_printk("  DEV_ACPI_HID(%s[%s])\t\tdevid: %02x:%02x.%x\n",
1400 				    hid, uid,
1401 				    PCI_BUS_NUM(devid),
1402 				    PCI_SLOT(devid),
1403 				    PCI_FUNC(devid));
1404 
1405 			flags = e->flags;
1406 
1407 			ret = add_acpi_hid_device(hid, uid, &devid, false);
1408 			if (ret)
1409 				return ret;
1410 
1411 			/*
1412 			 * add_special_device might update the devid in case a
1413 			 * command-line override is present. So call
1414 			 * set_dev_entry_from_acpi after add_special_device.
1415 			 */
1416 			set_dev_entry_from_acpi(iommu, devid, e->flags, 0);
1417 
1418 			break;
1419 		}
1420 		default:
1421 			break;
1422 		}
1423 
1424 		p += ivhd_entry_length(p);
1425 	}
1426 
1427 	return 0;
1428 }
1429 
1430 static void __init free_iommu_one(struct amd_iommu *iommu)
1431 {
1432 	free_cwwb_sem(iommu);
1433 	free_command_buffer(iommu);
1434 	free_event_buffer(iommu);
1435 	free_ppr_log(iommu);
1436 	free_ga_log(iommu);
1437 	iommu_unmap_mmio_space(iommu);
1438 }
1439 
1440 static void __init free_iommu_all(void)
1441 {
1442 	struct amd_iommu *iommu, *next;
1443 
1444 	for_each_iommu_safe(iommu, next) {
1445 		list_del(&iommu->list);
1446 		free_iommu_one(iommu);
1447 		kfree(iommu);
1448 	}
1449 }
1450 
1451 /*
1452  * Family15h Model 10h-1fh erratum 746 (IOMMU Logging May Stall Translations)
1453  * Workaround:
1454  *     BIOS should disable L2B micellaneous clock gating by setting
1455  *     L2_L2B_CK_GATE_CONTROL[CKGateL2BMiscDisable](D0F2xF4_x90[2]) = 1b
1456  */
1457 static void amd_iommu_erratum_746_workaround(struct amd_iommu *iommu)
1458 {
1459 	u32 value;
1460 
1461 	if ((boot_cpu_data.x86 != 0x15) ||
1462 	    (boot_cpu_data.x86_model < 0x10) ||
1463 	    (boot_cpu_data.x86_model > 0x1f))
1464 		return;
1465 
1466 	pci_write_config_dword(iommu->dev, 0xf0, 0x90);
1467 	pci_read_config_dword(iommu->dev, 0xf4, &value);
1468 
1469 	if (value & BIT(2))
1470 		return;
1471 
1472 	/* Select NB indirect register 0x90 and enable writing */
1473 	pci_write_config_dword(iommu->dev, 0xf0, 0x90 | (1 << 8));
1474 
1475 	pci_write_config_dword(iommu->dev, 0xf4, value | 0x4);
1476 	pci_info(iommu->dev, "Applying erratum 746 workaround\n");
1477 
1478 	/* Clear the enable writing bit */
1479 	pci_write_config_dword(iommu->dev, 0xf0, 0x90);
1480 }
1481 
1482 /*
1483  * Family15h Model 30h-3fh (IOMMU Mishandles ATS Write Permission)
1484  * Workaround:
1485  *     BIOS should enable ATS write permission check by setting
1486  *     L2_DEBUG_3[AtsIgnoreIWDis](D0F2xF4_x47[0]) = 1b
1487  */
1488 static void amd_iommu_ats_write_check_workaround(struct amd_iommu *iommu)
1489 {
1490 	u32 value;
1491 
1492 	if ((boot_cpu_data.x86 != 0x15) ||
1493 	    (boot_cpu_data.x86_model < 0x30) ||
1494 	    (boot_cpu_data.x86_model > 0x3f))
1495 		return;
1496 
1497 	/* Test L2_DEBUG_3[AtsIgnoreIWDis] == 1 */
1498 	value = iommu_read_l2(iommu, 0x47);
1499 
1500 	if (value & BIT(0))
1501 		return;
1502 
1503 	/* Set L2_DEBUG_3[AtsIgnoreIWDis] = 1 */
1504 	iommu_write_l2(iommu, 0x47, value | BIT(0));
1505 
1506 	pci_info(iommu->dev, "Applying ATS write check workaround\n");
1507 }
1508 
1509 /*
1510  * This function clues the initialization function for one IOMMU
1511  * together and also allocates the command buffer and programs the
1512  * hardware. It does NOT enable the IOMMU. This is done afterwards.
1513  */
1514 static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h)
1515 {
1516 	int ret;
1517 
1518 	raw_spin_lock_init(&iommu->lock);
1519 	iommu->cmd_sem_val = 0;
1520 
1521 	/* Add IOMMU to internal data structures */
1522 	list_add_tail(&iommu->list, &amd_iommu_list);
1523 	iommu->index = amd_iommus_present++;
1524 
1525 	if (unlikely(iommu->index >= MAX_IOMMUS)) {
1526 		WARN(1, "System has more IOMMUs than supported by this driver\n");
1527 		return -ENOSYS;
1528 	}
1529 
1530 	/* Index is fine - add IOMMU to the array */
1531 	amd_iommus[iommu->index] = iommu;
1532 
1533 	/*
1534 	 * Copy data from ACPI table entry to the iommu struct
1535 	 */
1536 	iommu->devid   = h->devid;
1537 	iommu->cap_ptr = h->cap_ptr;
1538 	iommu->pci_seg = h->pci_seg;
1539 	iommu->mmio_phys = h->mmio_phys;
1540 
1541 	switch (h->type) {
1542 	case 0x10:
1543 		/* Check if IVHD EFR contains proper max banks/counters */
1544 		if ((h->efr_attr != 0) &&
1545 		    ((h->efr_attr & (0xF << 13)) != 0) &&
1546 		    ((h->efr_attr & (0x3F << 17)) != 0))
1547 			iommu->mmio_phys_end = MMIO_REG_END_OFFSET;
1548 		else
1549 			iommu->mmio_phys_end = MMIO_CNTR_CONF_OFFSET;
1550 
1551 		/*
1552 		 * Note: GA (128-bit IRTE) mode requires cmpxchg16b supports.
1553 		 * GAM also requires GA mode. Therefore, we need to
1554 		 * check cmpxchg16b support before enabling it.
1555 		 */
1556 		if (!boot_cpu_has(X86_FEATURE_CX16) ||
1557 		    ((h->efr_attr & (0x1 << IOMMU_FEAT_GASUP_SHIFT)) == 0))
1558 			amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY;
1559 		break;
1560 	case 0x11:
1561 	case 0x40:
1562 		if (h->efr_reg & (1 << 9))
1563 			iommu->mmio_phys_end = MMIO_REG_END_OFFSET;
1564 		else
1565 			iommu->mmio_phys_end = MMIO_CNTR_CONF_OFFSET;
1566 
1567 		/*
1568 		 * Note: GA (128-bit IRTE) mode requires cmpxchg16b supports.
1569 		 * XT, GAM also requires GA mode. Therefore, we need to
1570 		 * check cmpxchg16b support before enabling them.
1571 		 */
1572 		if (!boot_cpu_has(X86_FEATURE_CX16) ||
1573 		    ((h->efr_reg & (0x1 << IOMMU_EFR_GASUP_SHIFT)) == 0)) {
1574 			amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY;
1575 			break;
1576 		}
1577 
1578 		/*
1579 		 * Note: Since iommu_update_intcapxt() leverages
1580 		 * the IOMMU MMIO access to MSI capability block registers
1581 		 * for MSI address lo/hi/data, we need to check both
1582 		 * EFR[XtSup] and EFR[MsiCapMmioSup] for x2APIC support.
1583 		 */
1584 		if ((h->efr_reg & BIT(IOMMU_EFR_XTSUP_SHIFT)) &&
1585 		    (h->efr_reg & BIT(IOMMU_EFR_MSICAPMMIOSUP_SHIFT)))
1586 			amd_iommu_xt_mode = IRQ_REMAP_X2APIC_MODE;
1587 		break;
1588 	default:
1589 		return -EINVAL;
1590 	}
1591 
1592 	iommu->mmio_base = iommu_map_mmio_space(iommu->mmio_phys,
1593 						iommu->mmio_phys_end);
1594 	if (!iommu->mmio_base)
1595 		return -ENOMEM;
1596 
1597 	if (alloc_cwwb_sem(iommu))
1598 		return -ENOMEM;
1599 
1600 	if (alloc_command_buffer(iommu))
1601 		return -ENOMEM;
1602 
1603 	if (alloc_event_buffer(iommu))
1604 		return -ENOMEM;
1605 
1606 	iommu->int_enabled = false;
1607 
1608 	init_translation_status(iommu);
1609 	if (translation_pre_enabled(iommu) && !is_kdump_kernel()) {
1610 		iommu_disable(iommu);
1611 		clear_translation_pre_enabled(iommu);
1612 		pr_warn("Translation was enabled for IOMMU:%d but we are not in kdump mode\n",
1613 			iommu->index);
1614 	}
1615 	if (amd_iommu_pre_enabled)
1616 		amd_iommu_pre_enabled = translation_pre_enabled(iommu);
1617 
1618 	ret = init_iommu_from_acpi(iommu, h);
1619 	if (ret)
1620 		return ret;
1621 
1622 	ret = amd_iommu_create_irq_domain(iommu);
1623 	if (ret)
1624 		return ret;
1625 
1626 	/*
1627 	 * Make sure IOMMU is not considered to translate itself. The IVRS
1628 	 * table tells us so, but this is a lie!
1629 	 */
1630 	amd_iommu_rlookup_table[iommu->devid] = NULL;
1631 
1632 	return 0;
1633 }
1634 
1635 /**
1636  * get_highest_supported_ivhd_type - Look up the appropriate IVHD type
1637  * @ivrs: Pointer to the IVRS header
1638  *
1639  * This function search through all IVDB of the maximum supported IVHD
1640  */
1641 static u8 get_highest_supported_ivhd_type(struct acpi_table_header *ivrs)
1642 {
1643 	u8 *base = (u8 *)ivrs;
1644 	struct ivhd_header *ivhd = (struct ivhd_header *)
1645 					(base + IVRS_HEADER_LENGTH);
1646 	u8 last_type = ivhd->type;
1647 	u16 devid = ivhd->devid;
1648 
1649 	while (((u8 *)ivhd - base < ivrs->length) &&
1650 	       (ivhd->type <= ACPI_IVHD_TYPE_MAX_SUPPORTED)) {
1651 		u8 *p = (u8 *) ivhd;
1652 
1653 		if (ivhd->devid == devid)
1654 			last_type = ivhd->type;
1655 		ivhd = (struct ivhd_header *)(p + ivhd->length);
1656 	}
1657 
1658 	return last_type;
1659 }
1660 
1661 /*
1662  * Iterates over all IOMMU entries in the ACPI table, allocates the
1663  * IOMMU structure and initializes it with init_iommu_one()
1664  */
1665 static int __init init_iommu_all(struct acpi_table_header *table)
1666 {
1667 	u8 *p = (u8 *)table, *end = (u8 *)table;
1668 	struct ivhd_header *h;
1669 	struct amd_iommu *iommu;
1670 	int ret;
1671 
1672 	end += table->length;
1673 	p += IVRS_HEADER_LENGTH;
1674 
1675 	while (p < end) {
1676 		h = (struct ivhd_header *)p;
1677 		if (*p == amd_iommu_target_ivhd_type) {
1678 
1679 			DUMP_printk("device: %02x:%02x.%01x cap: %04x "
1680 				    "seg: %d flags: %01x info %04x\n",
1681 				    PCI_BUS_NUM(h->devid), PCI_SLOT(h->devid),
1682 				    PCI_FUNC(h->devid), h->cap_ptr,
1683 				    h->pci_seg, h->flags, h->info);
1684 			DUMP_printk("       mmio-addr: %016llx\n",
1685 				    h->mmio_phys);
1686 
1687 			iommu = kzalloc(sizeof(struct amd_iommu), GFP_KERNEL);
1688 			if (iommu == NULL)
1689 				return -ENOMEM;
1690 
1691 			ret = init_iommu_one(iommu, h);
1692 			if (ret)
1693 				return ret;
1694 		}
1695 		p += h->length;
1696 
1697 	}
1698 	WARN_ON(p != end);
1699 
1700 	return 0;
1701 }
1702 
1703 static int iommu_pc_get_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr,
1704 				u8 fxn, u64 *value, bool is_write);
1705 
1706 static void init_iommu_perf_ctr(struct amd_iommu *iommu)
1707 {
1708 	struct pci_dev *pdev = iommu->dev;
1709 	u64 val = 0xabcd, val2 = 0, save_reg = 0;
1710 
1711 	if (!iommu_feature(iommu, FEATURE_PC))
1712 		return;
1713 
1714 	amd_iommu_pc_present = true;
1715 
1716 	/* save the value to restore, if writable */
1717 	if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &save_reg, false))
1718 		goto pc_false;
1719 
1720 	/* Check if the performance counters can be written to */
1721 	if ((iommu_pc_get_set_reg(iommu, 0, 0, 0, &val, true)) ||
1722 	    (iommu_pc_get_set_reg(iommu, 0, 0, 0, &val2, false)) ||
1723 	    (val != val2))
1724 		goto pc_false;
1725 
1726 	/* restore */
1727 	if (iommu_pc_get_set_reg(iommu, 0, 0, 0, &save_reg, true))
1728 		goto pc_false;
1729 
1730 	pci_info(pdev, "IOMMU performance counters supported\n");
1731 
1732 	val = readl(iommu->mmio_base + MMIO_CNTR_CONF_OFFSET);
1733 	iommu->max_banks = (u8) ((val >> 12) & 0x3f);
1734 	iommu->max_counters = (u8) ((val >> 7) & 0xf);
1735 
1736 	return;
1737 
1738 pc_false:
1739 	pci_err(pdev, "Unable to read/write to IOMMU perf counter.\n");
1740 	amd_iommu_pc_present = false;
1741 	return;
1742 }
1743 
1744 static ssize_t amd_iommu_show_cap(struct device *dev,
1745 				  struct device_attribute *attr,
1746 				  char *buf)
1747 {
1748 	struct amd_iommu *iommu = dev_to_amd_iommu(dev);
1749 	return sprintf(buf, "%x\n", iommu->cap);
1750 }
1751 static DEVICE_ATTR(cap, S_IRUGO, amd_iommu_show_cap, NULL);
1752 
1753 static ssize_t amd_iommu_show_features(struct device *dev,
1754 				       struct device_attribute *attr,
1755 				       char *buf)
1756 {
1757 	struct amd_iommu *iommu = dev_to_amd_iommu(dev);
1758 	return sprintf(buf, "%llx\n", iommu->features);
1759 }
1760 static DEVICE_ATTR(features, S_IRUGO, amd_iommu_show_features, NULL);
1761 
1762 static struct attribute *amd_iommu_attrs[] = {
1763 	&dev_attr_cap.attr,
1764 	&dev_attr_features.attr,
1765 	NULL,
1766 };
1767 
1768 static struct attribute_group amd_iommu_group = {
1769 	.name = "amd-iommu",
1770 	.attrs = amd_iommu_attrs,
1771 };
1772 
1773 static const struct attribute_group *amd_iommu_groups[] = {
1774 	&amd_iommu_group,
1775 	NULL,
1776 };
1777 
1778 static int __init iommu_init_pci(struct amd_iommu *iommu)
1779 {
1780 	int cap_ptr = iommu->cap_ptr;
1781 	int ret;
1782 
1783 	iommu->dev = pci_get_domain_bus_and_slot(0, PCI_BUS_NUM(iommu->devid),
1784 						 iommu->devid & 0xff);
1785 	if (!iommu->dev)
1786 		return -ENODEV;
1787 
1788 	/* Prevent binding other PCI device drivers to IOMMU devices */
1789 	iommu->dev->match_driver = false;
1790 
1791 	pci_read_config_dword(iommu->dev, cap_ptr + MMIO_CAP_HDR_OFFSET,
1792 			      &iommu->cap);
1793 
1794 	if (!(iommu->cap & (1 << IOMMU_CAP_IOTLB)))
1795 		amd_iommu_iotlb_sup = false;
1796 
1797 	/* read extended feature bits */
1798 	iommu->features = readq(iommu->mmio_base + MMIO_EXT_FEATURES);
1799 
1800 	if (iommu_feature(iommu, FEATURE_GT)) {
1801 		int glxval;
1802 		u32 max_pasid;
1803 		u64 pasmax;
1804 
1805 		pasmax = iommu->features & FEATURE_PASID_MASK;
1806 		pasmax >>= FEATURE_PASID_SHIFT;
1807 		max_pasid  = (1 << (pasmax + 1)) - 1;
1808 
1809 		amd_iommu_max_pasid = min(amd_iommu_max_pasid, max_pasid);
1810 
1811 		BUG_ON(amd_iommu_max_pasid & ~PASID_MASK);
1812 
1813 		glxval   = iommu->features & FEATURE_GLXVAL_MASK;
1814 		glxval >>= FEATURE_GLXVAL_SHIFT;
1815 
1816 		if (amd_iommu_max_glx_val == -1)
1817 			amd_iommu_max_glx_val = glxval;
1818 		else
1819 			amd_iommu_max_glx_val = min(amd_iommu_max_glx_val, glxval);
1820 	}
1821 
1822 	if (iommu_feature(iommu, FEATURE_GT) &&
1823 	    iommu_feature(iommu, FEATURE_PPR)) {
1824 		iommu->is_iommu_v2   = true;
1825 		amd_iommu_v2_present = true;
1826 	}
1827 
1828 	if (iommu_feature(iommu, FEATURE_PPR) && alloc_ppr_log(iommu))
1829 		return -ENOMEM;
1830 
1831 	ret = iommu_init_ga(iommu);
1832 	if (ret)
1833 		return ret;
1834 
1835 	if (iommu->cap & (1UL << IOMMU_CAP_NPCACHE))
1836 		amd_iommu_np_cache = true;
1837 
1838 	init_iommu_perf_ctr(iommu);
1839 
1840 	if (is_rd890_iommu(iommu->dev)) {
1841 		int i, j;
1842 
1843 		iommu->root_pdev =
1844 			pci_get_domain_bus_and_slot(0, iommu->dev->bus->number,
1845 						    PCI_DEVFN(0, 0));
1846 
1847 		/*
1848 		 * Some rd890 systems may not be fully reconfigured by the
1849 		 * BIOS, so it's necessary for us to store this information so
1850 		 * it can be reprogrammed on resume
1851 		 */
1852 		pci_read_config_dword(iommu->dev, iommu->cap_ptr + 4,
1853 				&iommu->stored_addr_lo);
1854 		pci_read_config_dword(iommu->dev, iommu->cap_ptr + 8,
1855 				&iommu->stored_addr_hi);
1856 
1857 		/* Low bit locks writes to configuration space */
1858 		iommu->stored_addr_lo &= ~1;
1859 
1860 		for (i = 0; i < 6; i++)
1861 			for (j = 0; j < 0x12; j++)
1862 				iommu->stored_l1[i][j] = iommu_read_l1(iommu, i, j);
1863 
1864 		for (i = 0; i < 0x83; i++)
1865 			iommu->stored_l2[i] = iommu_read_l2(iommu, i);
1866 	}
1867 
1868 	amd_iommu_erratum_746_workaround(iommu);
1869 	amd_iommu_ats_write_check_workaround(iommu);
1870 
1871 	iommu_device_sysfs_add(&iommu->iommu, &iommu->dev->dev,
1872 			       amd_iommu_groups, "ivhd%d", iommu->index);
1873 	iommu_device_set_ops(&iommu->iommu, &amd_iommu_ops);
1874 	iommu_device_register(&iommu->iommu);
1875 
1876 	return pci_enable_device(iommu->dev);
1877 }
1878 
1879 static void print_iommu_info(void)
1880 {
1881 	static const char * const feat_str[] = {
1882 		"PreF", "PPR", "X2APIC", "NX", "GT", "[5]",
1883 		"IA", "GA", "HE", "PC"
1884 	};
1885 	struct amd_iommu *iommu;
1886 
1887 	for_each_iommu(iommu) {
1888 		struct pci_dev *pdev = iommu->dev;
1889 		int i;
1890 
1891 		pci_info(pdev, "Found IOMMU cap 0x%hx\n", iommu->cap_ptr);
1892 
1893 		if (iommu->cap & (1 << IOMMU_CAP_EFR)) {
1894 			pci_info(pdev, "Extended features (%#llx):",
1895 				 iommu->features);
1896 			for (i = 0; i < ARRAY_SIZE(feat_str); ++i) {
1897 				if (iommu_feature(iommu, (1ULL << i)))
1898 					pr_cont(" %s", feat_str[i]);
1899 			}
1900 
1901 			if (iommu->features & FEATURE_GAM_VAPIC)
1902 				pr_cont(" GA_vAPIC");
1903 
1904 			pr_cont("\n");
1905 		}
1906 	}
1907 	if (irq_remapping_enabled) {
1908 		pr_info("Interrupt remapping enabled\n");
1909 		if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
1910 			pr_info("Virtual APIC enabled\n");
1911 		if (amd_iommu_xt_mode == IRQ_REMAP_X2APIC_MODE)
1912 			pr_info("X2APIC enabled\n");
1913 	}
1914 }
1915 
1916 static int __init amd_iommu_init_pci(void)
1917 {
1918 	struct amd_iommu *iommu;
1919 	int ret = 0;
1920 
1921 	for_each_iommu(iommu) {
1922 		ret = iommu_init_pci(iommu);
1923 		if (ret)
1924 			break;
1925 
1926 		/* Need to setup range after PCI init */
1927 		iommu_set_cwwb_range(iommu);
1928 	}
1929 
1930 	/*
1931 	 * Order is important here to make sure any unity map requirements are
1932 	 * fulfilled. The unity mappings are created and written to the device
1933 	 * table during the amd_iommu_init_api() call.
1934 	 *
1935 	 * After that we call init_device_table_dma() to make sure any
1936 	 * uninitialized DTE will block DMA, and in the end we flush the caches
1937 	 * of all IOMMUs to make sure the changes to the device table are
1938 	 * active.
1939 	 */
1940 	ret = amd_iommu_init_api();
1941 
1942 	init_device_table_dma();
1943 
1944 	for_each_iommu(iommu)
1945 		iommu_flush_all_caches(iommu);
1946 
1947 	if (!ret)
1948 		print_iommu_info();
1949 
1950 	return ret;
1951 }
1952 
1953 /****************************************************************************
1954  *
1955  * The following functions initialize the MSI interrupts for all IOMMUs
1956  * in the system. It's a bit challenging because there could be multiple
1957  * IOMMUs per PCI BDF but we can call pci_enable_msi(x) only once per
1958  * pci_dev.
1959  *
1960  ****************************************************************************/
1961 
1962 static int iommu_setup_msi(struct amd_iommu *iommu)
1963 {
1964 	int r;
1965 
1966 	r = pci_enable_msi(iommu->dev);
1967 	if (r)
1968 		return r;
1969 
1970 	r = request_threaded_irq(iommu->dev->irq,
1971 				 amd_iommu_int_handler,
1972 				 amd_iommu_int_thread,
1973 				 0, "AMD-Vi",
1974 				 iommu);
1975 
1976 	if (r) {
1977 		pci_disable_msi(iommu->dev);
1978 		return r;
1979 	}
1980 
1981 	iommu->int_enabled = true;
1982 
1983 	return 0;
1984 }
1985 
1986 #define XT_INT_DEST_MODE(x)	(((x) & 0x1ULL) << 2)
1987 #define XT_INT_DEST_LO(x)	(((x) & 0xFFFFFFULL) << 8)
1988 #define XT_INT_VEC(x)		(((x) & 0xFFULL) << 32)
1989 #define XT_INT_DEST_HI(x)	((((x) >> 24) & 0xFFULL) << 56)
1990 
1991 /*
1992  * Setup the IntCapXT registers with interrupt routing information
1993  * based on the PCI MSI capability block registers, accessed via
1994  * MMIO MSI address low/hi and MSI data registers.
1995  */
1996 static void iommu_update_intcapxt(struct amd_iommu *iommu)
1997 {
1998 	u64 val;
1999 	u32 addr_lo = readl(iommu->mmio_base + MMIO_MSI_ADDR_LO_OFFSET);
2000 	u32 addr_hi = readl(iommu->mmio_base + MMIO_MSI_ADDR_HI_OFFSET);
2001 	u32 data    = readl(iommu->mmio_base + MMIO_MSI_DATA_OFFSET);
2002 	bool dm     = (addr_lo >> MSI_ADDR_DEST_MODE_SHIFT) & 0x1;
2003 	u32 dest    = ((addr_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xFF);
2004 
2005 	if (x2apic_enabled())
2006 		dest |= MSI_ADDR_EXT_DEST_ID(addr_hi);
2007 
2008 	val = XT_INT_VEC(data & 0xFF) |
2009 	      XT_INT_DEST_MODE(dm) |
2010 	      XT_INT_DEST_LO(dest) |
2011 	      XT_INT_DEST_HI(dest);
2012 
2013 	/**
2014 	 * Current IOMMU implemtation uses the same IRQ for all
2015 	 * 3 IOMMU interrupts.
2016 	 */
2017 	writeq(val, iommu->mmio_base + MMIO_INTCAPXT_EVT_OFFSET);
2018 	writeq(val, iommu->mmio_base + MMIO_INTCAPXT_PPR_OFFSET);
2019 	writeq(val, iommu->mmio_base + MMIO_INTCAPXT_GALOG_OFFSET);
2020 }
2021 
2022 static void _irq_notifier_notify(struct irq_affinity_notify *notify,
2023 				 const cpumask_t *mask)
2024 {
2025 	struct amd_iommu *iommu;
2026 
2027 	for_each_iommu(iommu) {
2028 		if (iommu->dev->irq == notify->irq) {
2029 			iommu_update_intcapxt(iommu);
2030 			break;
2031 		}
2032 	}
2033 }
2034 
2035 static void _irq_notifier_release(struct kref *ref)
2036 {
2037 }
2038 
2039 static int iommu_init_intcapxt(struct amd_iommu *iommu)
2040 {
2041 	int ret;
2042 	struct irq_affinity_notify *notify = &iommu->intcapxt_notify;
2043 
2044 	/**
2045 	 * IntCapXT requires XTSup=1 and MsiCapMmioSup=1,
2046 	 * which can be inferred from amd_iommu_xt_mode.
2047 	 */
2048 	if (amd_iommu_xt_mode != IRQ_REMAP_X2APIC_MODE)
2049 		return 0;
2050 
2051 	/**
2052 	 * Also, we need to setup notifier to update the IntCapXT registers
2053 	 * whenever the irq affinity is changed from user-space.
2054 	 */
2055 	notify->irq = iommu->dev->irq;
2056 	notify->notify = _irq_notifier_notify,
2057 	notify->release = _irq_notifier_release,
2058 	ret = irq_set_affinity_notifier(iommu->dev->irq, notify);
2059 	if (ret) {
2060 		pr_err("Failed to register irq affinity notifier (devid=%#x, irq %d)\n",
2061 		       iommu->devid, iommu->dev->irq);
2062 		return ret;
2063 	}
2064 
2065 	iommu_update_intcapxt(iommu);
2066 	iommu_feature_enable(iommu, CONTROL_INTCAPXT_EN);
2067 	return ret;
2068 }
2069 
2070 static int iommu_init_msi(struct amd_iommu *iommu)
2071 {
2072 	int ret;
2073 
2074 	if (iommu->int_enabled)
2075 		goto enable_faults;
2076 
2077 	if (iommu->dev->msi_cap)
2078 		ret = iommu_setup_msi(iommu);
2079 	else
2080 		ret = -ENODEV;
2081 
2082 	if (ret)
2083 		return ret;
2084 
2085 enable_faults:
2086 	ret = iommu_init_intcapxt(iommu);
2087 	if (ret)
2088 		return ret;
2089 
2090 	iommu_feature_enable(iommu, CONTROL_EVT_INT_EN);
2091 
2092 	if (iommu->ppr_log != NULL)
2093 		iommu_feature_enable(iommu, CONTROL_PPRINT_EN);
2094 
2095 	iommu_ga_log_enable(iommu);
2096 
2097 	return 0;
2098 }
2099 
2100 /****************************************************************************
2101  *
2102  * The next functions belong to the third pass of parsing the ACPI
2103  * table. In this last pass the memory mapping requirements are
2104  * gathered (like exclusion and unity mapping ranges).
2105  *
2106  ****************************************************************************/
2107 
2108 static void __init free_unity_maps(void)
2109 {
2110 	struct unity_map_entry *entry, *next;
2111 
2112 	list_for_each_entry_safe(entry, next, &amd_iommu_unity_map, list) {
2113 		list_del(&entry->list);
2114 		kfree(entry);
2115 	}
2116 }
2117 
2118 /* called for unity map ACPI definition */
2119 static int __init init_unity_map_range(struct ivmd_header *m)
2120 {
2121 	struct unity_map_entry *e = NULL;
2122 	char *s;
2123 
2124 	e = kzalloc(sizeof(*e), GFP_KERNEL);
2125 	if (e == NULL)
2126 		return -ENOMEM;
2127 
2128 	switch (m->type) {
2129 	default:
2130 		kfree(e);
2131 		return 0;
2132 	case ACPI_IVMD_TYPE:
2133 		s = "IVMD_TYPEi\t\t\t";
2134 		e->devid_start = e->devid_end = m->devid;
2135 		break;
2136 	case ACPI_IVMD_TYPE_ALL:
2137 		s = "IVMD_TYPE_ALL\t\t";
2138 		e->devid_start = 0;
2139 		e->devid_end = amd_iommu_last_bdf;
2140 		break;
2141 	case ACPI_IVMD_TYPE_RANGE:
2142 		s = "IVMD_TYPE_RANGE\t\t";
2143 		e->devid_start = m->devid;
2144 		e->devid_end = m->aux;
2145 		break;
2146 	}
2147 	e->address_start = PAGE_ALIGN(m->range_start);
2148 	e->address_end = e->address_start + PAGE_ALIGN(m->range_length);
2149 	e->prot = m->flags >> 1;
2150 
2151 	/*
2152 	 * Treat per-device exclusion ranges as r/w unity-mapped regions
2153 	 * since some buggy BIOSes might lead to the overwritten exclusion
2154 	 * range (exclusion_start and exclusion_length members). This
2155 	 * happens when there are multiple exclusion ranges (IVMD entries)
2156 	 * defined in ACPI table.
2157 	 */
2158 	if (m->flags & IVMD_FLAG_EXCL_RANGE)
2159 		e->prot = (IVMD_FLAG_IW | IVMD_FLAG_IR) >> 1;
2160 
2161 	DUMP_printk("%s devid_start: %02x:%02x.%x devid_end: %02x:%02x.%x"
2162 		    " range_start: %016llx range_end: %016llx flags: %x\n", s,
2163 		    PCI_BUS_NUM(e->devid_start), PCI_SLOT(e->devid_start),
2164 		    PCI_FUNC(e->devid_start), PCI_BUS_NUM(e->devid_end),
2165 		    PCI_SLOT(e->devid_end), PCI_FUNC(e->devid_end),
2166 		    e->address_start, e->address_end, m->flags);
2167 
2168 	list_add_tail(&e->list, &amd_iommu_unity_map);
2169 
2170 	return 0;
2171 }
2172 
2173 /* iterates over all memory definitions we find in the ACPI table */
2174 static int __init init_memory_definitions(struct acpi_table_header *table)
2175 {
2176 	u8 *p = (u8 *)table, *end = (u8 *)table;
2177 	struct ivmd_header *m;
2178 
2179 	end += table->length;
2180 	p += IVRS_HEADER_LENGTH;
2181 
2182 	while (p < end) {
2183 		m = (struct ivmd_header *)p;
2184 		if (m->flags & (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))
2185 			init_unity_map_range(m);
2186 
2187 		p += m->length;
2188 	}
2189 
2190 	return 0;
2191 }
2192 
2193 /*
2194  * Init the device table to not allow DMA access for devices
2195  */
2196 static void init_device_table_dma(void)
2197 {
2198 	u32 devid;
2199 
2200 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) {
2201 		set_dev_entry_bit(devid, DEV_ENTRY_VALID);
2202 		set_dev_entry_bit(devid, DEV_ENTRY_TRANSLATION);
2203 	}
2204 }
2205 
2206 static void __init uninit_device_table_dma(void)
2207 {
2208 	u32 devid;
2209 
2210 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) {
2211 		amd_iommu_dev_table[devid].data[0] = 0ULL;
2212 		amd_iommu_dev_table[devid].data[1] = 0ULL;
2213 	}
2214 }
2215 
2216 static void init_device_table(void)
2217 {
2218 	u32 devid;
2219 
2220 	if (!amd_iommu_irq_remap)
2221 		return;
2222 
2223 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid)
2224 		set_dev_entry_bit(devid, DEV_ENTRY_IRQ_TBL_EN);
2225 }
2226 
2227 static void iommu_init_flags(struct amd_iommu *iommu)
2228 {
2229 	iommu->acpi_flags & IVHD_FLAG_HT_TUN_EN_MASK ?
2230 		iommu_feature_enable(iommu, CONTROL_HT_TUN_EN) :
2231 		iommu_feature_disable(iommu, CONTROL_HT_TUN_EN);
2232 
2233 	iommu->acpi_flags & IVHD_FLAG_PASSPW_EN_MASK ?
2234 		iommu_feature_enable(iommu, CONTROL_PASSPW_EN) :
2235 		iommu_feature_disable(iommu, CONTROL_PASSPW_EN);
2236 
2237 	iommu->acpi_flags & IVHD_FLAG_RESPASSPW_EN_MASK ?
2238 		iommu_feature_enable(iommu, CONTROL_RESPASSPW_EN) :
2239 		iommu_feature_disable(iommu, CONTROL_RESPASSPW_EN);
2240 
2241 	iommu->acpi_flags & IVHD_FLAG_ISOC_EN_MASK ?
2242 		iommu_feature_enable(iommu, CONTROL_ISOC_EN) :
2243 		iommu_feature_disable(iommu, CONTROL_ISOC_EN);
2244 
2245 	/*
2246 	 * make IOMMU memory accesses cache coherent
2247 	 */
2248 	iommu_feature_enable(iommu, CONTROL_COHERENT_EN);
2249 
2250 	/* Set IOTLB invalidation timeout to 1s */
2251 	iommu_set_inv_tlb_timeout(iommu, CTRL_INV_TO_1S);
2252 }
2253 
2254 static void iommu_apply_resume_quirks(struct amd_iommu *iommu)
2255 {
2256 	int i, j;
2257 	u32 ioc_feature_control;
2258 	struct pci_dev *pdev = iommu->root_pdev;
2259 
2260 	/* RD890 BIOSes may not have completely reconfigured the iommu */
2261 	if (!is_rd890_iommu(iommu->dev) || !pdev)
2262 		return;
2263 
2264 	/*
2265 	 * First, we need to ensure that the iommu is enabled. This is
2266 	 * controlled by a register in the northbridge
2267 	 */
2268 
2269 	/* Select Northbridge indirect register 0x75 and enable writing */
2270 	pci_write_config_dword(pdev, 0x60, 0x75 | (1 << 7));
2271 	pci_read_config_dword(pdev, 0x64, &ioc_feature_control);
2272 
2273 	/* Enable the iommu */
2274 	if (!(ioc_feature_control & 0x1))
2275 		pci_write_config_dword(pdev, 0x64, ioc_feature_control | 1);
2276 
2277 	/* Restore the iommu BAR */
2278 	pci_write_config_dword(iommu->dev, iommu->cap_ptr + 4,
2279 			       iommu->stored_addr_lo);
2280 	pci_write_config_dword(iommu->dev, iommu->cap_ptr + 8,
2281 			       iommu->stored_addr_hi);
2282 
2283 	/* Restore the l1 indirect regs for each of the 6 l1s */
2284 	for (i = 0; i < 6; i++)
2285 		for (j = 0; j < 0x12; j++)
2286 			iommu_write_l1(iommu, i, j, iommu->stored_l1[i][j]);
2287 
2288 	/* Restore the l2 indirect regs */
2289 	for (i = 0; i < 0x83; i++)
2290 		iommu_write_l2(iommu, i, iommu->stored_l2[i]);
2291 
2292 	/* Lock PCI setup registers */
2293 	pci_write_config_dword(iommu->dev, iommu->cap_ptr + 4,
2294 			       iommu->stored_addr_lo | 1);
2295 }
2296 
2297 static void iommu_enable_ga(struct amd_iommu *iommu)
2298 {
2299 #ifdef CONFIG_IRQ_REMAP
2300 	switch (amd_iommu_guest_ir) {
2301 	case AMD_IOMMU_GUEST_IR_VAPIC:
2302 		iommu_feature_enable(iommu, CONTROL_GAM_EN);
2303 		fallthrough;
2304 	case AMD_IOMMU_GUEST_IR_LEGACY_GA:
2305 		iommu_feature_enable(iommu, CONTROL_GA_EN);
2306 		iommu->irte_ops = &irte_128_ops;
2307 		break;
2308 	default:
2309 		iommu->irte_ops = &irte_32_ops;
2310 		break;
2311 	}
2312 #endif
2313 }
2314 
2315 static void early_enable_iommu(struct amd_iommu *iommu)
2316 {
2317 	iommu_disable(iommu);
2318 	iommu_init_flags(iommu);
2319 	iommu_set_device_table(iommu);
2320 	iommu_enable_command_buffer(iommu);
2321 	iommu_enable_event_buffer(iommu);
2322 	iommu_set_exclusion_range(iommu);
2323 	iommu_enable_ga(iommu);
2324 	iommu_enable_xt(iommu);
2325 	iommu_enable(iommu);
2326 	iommu_flush_all_caches(iommu);
2327 }
2328 
2329 /*
2330  * This function finally enables all IOMMUs found in the system after
2331  * they have been initialized.
2332  *
2333  * Or if in kdump kernel and IOMMUs are all pre-enabled, try to copy
2334  * the old content of device table entries. Not this case or copy failed,
2335  * just continue as normal kernel does.
2336  */
2337 static void early_enable_iommus(void)
2338 {
2339 	struct amd_iommu *iommu;
2340 
2341 
2342 	if (!copy_device_table()) {
2343 		/*
2344 		 * If come here because of failure in copying device table from old
2345 		 * kernel with all IOMMUs enabled, print error message and try to
2346 		 * free allocated old_dev_tbl_cpy.
2347 		 */
2348 		if (amd_iommu_pre_enabled)
2349 			pr_err("Failed to copy DEV table from previous kernel.\n");
2350 		if (old_dev_tbl_cpy != NULL)
2351 			free_pages((unsigned long)old_dev_tbl_cpy,
2352 					get_order(dev_table_size));
2353 
2354 		for_each_iommu(iommu) {
2355 			clear_translation_pre_enabled(iommu);
2356 			early_enable_iommu(iommu);
2357 		}
2358 	} else {
2359 		pr_info("Copied DEV table from previous kernel.\n");
2360 		free_pages((unsigned long)amd_iommu_dev_table,
2361 				get_order(dev_table_size));
2362 		amd_iommu_dev_table = old_dev_tbl_cpy;
2363 		for_each_iommu(iommu) {
2364 			iommu_disable_command_buffer(iommu);
2365 			iommu_disable_event_buffer(iommu);
2366 			iommu_enable_command_buffer(iommu);
2367 			iommu_enable_event_buffer(iommu);
2368 			iommu_enable_ga(iommu);
2369 			iommu_enable_xt(iommu);
2370 			iommu_set_device_table(iommu);
2371 			iommu_flush_all_caches(iommu);
2372 		}
2373 	}
2374 
2375 #ifdef CONFIG_IRQ_REMAP
2376 	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
2377 		amd_iommu_irq_ops.capability |= (1 << IRQ_POSTING_CAP);
2378 #endif
2379 }
2380 
2381 static void enable_iommus_v2(void)
2382 {
2383 	struct amd_iommu *iommu;
2384 
2385 	for_each_iommu(iommu) {
2386 		iommu_enable_ppr_log(iommu);
2387 		iommu_enable_gt(iommu);
2388 	}
2389 }
2390 
2391 static void enable_iommus(void)
2392 {
2393 	early_enable_iommus();
2394 
2395 	enable_iommus_v2();
2396 }
2397 
2398 static void disable_iommus(void)
2399 {
2400 	struct amd_iommu *iommu;
2401 
2402 	for_each_iommu(iommu)
2403 		iommu_disable(iommu);
2404 
2405 #ifdef CONFIG_IRQ_REMAP
2406 	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
2407 		amd_iommu_irq_ops.capability &= ~(1 << IRQ_POSTING_CAP);
2408 #endif
2409 }
2410 
2411 /*
2412  * Suspend/Resume support
2413  * disable suspend until real resume implemented
2414  */
2415 
2416 static void amd_iommu_resume(void)
2417 {
2418 	struct amd_iommu *iommu;
2419 
2420 	for_each_iommu(iommu)
2421 		iommu_apply_resume_quirks(iommu);
2422 
2423 	/* re-load the hardware */
2424 	enable_iommus();
2425 
2426 	amd_iommu_enable_interrupts();
2427 }
2428 
2429 static int amd_iommu_suspend(void)
2430 {
2431 	/* disable IOMMUs to go out of the way for BIOS */
2432 	disable_iommus();
2433 
2434 	return 0;
2435 }
2436 
2437 static struct syscore_ops amd_iommu_syscore_ops = {
2438 	.suspend = amd_iommu_suspend,
2439 	.resume = amd_iommu_resume,
2440 };
2441 
2442 static void __init free_iommu_resources(void)
2443 {
2444 	kmemleak_free(irq_lookup_table);
2445 	free_pages((unsigned long)irq_lookup_table,
2446 		   get_order(rlookup_table_size));
2447 	irq_lookup_table = NULL;
2448 
2449 	kmem_cache_destroy(amd_iommu_irq_cache);
2450 	amd_iommu_irq_cache = NULL;
2451 
2452 	free_pages((unsigned long)amd_iommu_rlookup_table,
2453 		   get_order(rlookup_table_size));
2454 	amd_iommu_rlookup_table = NULL;
2455 
2456 	free_pages((unsigned long)amd_iommu_alias_table,
2457 		   get_order(alias_table_size));
2458 	amd_iommu_alias_table = NULL;
2459 
2460 	free_pages((unsigned long)amd_iommu_dev_table,
2461 		   get_order(dev_table_size));
2462 	amd_iommu_dev_table = NULL;
2463 
2464 	free_iommu_all();
2465 }
2466 
2467 /* SB IOAPIC is always on this device in AMD systems */
2468 #define IOAPIC_SB_DEVID		((0x00 << 8) | PCI_DEVFN(0x14, 0))
2469 
2470 static bool __init check_ioapic_information(void)
2471 {
2472 	const char *fw_bug = FW_BUG;
2473 	bool ret, has_sb_ioapic;
2474 	int idx;
2475 
2476 	has_sb_ioapic = false;
2477 	ret           = false;
2478 
2479 	/*
2480 	 * If we have map overrides on the kernel command line the
2481 	 * messages in this function might not describe firmware bugs
2482 	 * anymore - so be careful
2483 	 */
2484 	if (cmdline_maps)
2485 		fw_bug = "";
2486 
2487 	for (idx = 0; idx < nr_ioapics; idx++) {
2488 		int devid, id = mpc_ioapic_id(idx);
2489 
2490 		devid = get_ioapic_devid(id);
2491 		if (devid < 0) {
2492 			pr_err("%s: IOAPIC[%d] not in IVRS table\n",
2493 				fw_bug, id);
2494 			ret = false;
2495 		} else if (devid == IOAPIC_SB_DEVID) {
2496 			has_sb_ioapic = true;
2497 			ret           = true;
2498 		}
2499 	}
2500 
2501 	if (!has_sb_ioapic) {
2502 		/*
2503 		 * We expect the SB IOAPIC to be listed in the IVRS
2504 		 * table. The system timer is connected to the SB IOAPIC
2505 		 * and if we don't have it in the list the system will
2506 		 * panic at boot time.  This situation usually happens
2507 		 * when the BIOS is buggy and provides us the wrong
2508 		 * device id for the IOAPIC in the system.
2509 		 */
2510 		pr_err("%s: No southbridge IOAPIC found\n", fw_bug);
2511 	}
2512 
2513 	if (!ret)
2514 		pr_err("Disabling interrupt remapping\n");
2515 
2516 	return ret;
2517 }
2518 
2519 static void __init free_dma_resources(void)
2520 {
2521 	free_pages((unsigned long)amd_iommu_pd_alloc_bitmap,
2522 		   get_order(MAX_DOMAIN_ID/8));
2523 	amd_iommu_pd_alloc_bitmap = NULL;
2524 
2525 	free_unity_maps();
2526 }
2527 
2528 /*
2529  * This is the hardware init function for AMD IOMMU in the system.
2530  * This function is called either from amd_iommu_init or from the interrupt
2531  * remapping setup code.
2532  *
2533  * This function basically parses the ACPI table for AMD IOMMU (IVRS)
2534  * four times:
2535  *
2536  *	1 pass) Discover the most comprehensive IVHD type to use.
2537  *
2538  *	2 pass) Find the highest PCI device id the driver has to handle.
2539  *		Upon this information the size of the data structures is
2540  *		determined that needs to be allocated.
2541  *
2542  *	3 pass) Initialize the data structures just allocated with the
2543  *		information in the ACPI table about available AMD IOMMUs
2544  *		in the system. It also maps the PCI devices in the
2545  *		system to specific IOMMUs
2546  *
2547  *	4 pass) After the basic data structures are allocated and
2548  *		initialized we update them with information about memory
2549  *		remapping requirements parsed out of the ACPI table in
2550  *		this last pass.
2551  *
2552  * After everything is set up the IOMMUs are enabled and the necessary
2553  * hotplug and suspend notifiers are registered.
2554  */
2555 static int __init early_amd_iommu_init(void)
2556 {
2557 	struct acpi_table_header *ivrs_base;
2558 	acpi_status status;
2559 	int i, remap_cache_sz, ret = 0;
2560 	u32 pci_id;
2561 
2562 	if (!amd_iommu_detected)
2563 		return -ENODEV;
2564 
2565 	status = acpi_get_table("IVRS", 0, &ivrs_base);
2566 	if (status == AE_NOT_FOUND)
2567 		return -ENODEV;
2568 	else if (ACPI_FAILURE(status)) {
2569 		const char *err = acpi_format_exception(status);
2570 		pr_err("IVRS table error: %s\n", err);
2571 		return -EINVAL;
2572 	}
2573 
2574 	/*
2575 	 * Validate checksum here so we don't need to do it when
2576 	 * we actually parse the table
2577 	 */
2578 	ret = check_ivrs_checksum(ivrs_base);
2579 	if (ret)
2580 		goto out;
2581 
2582 	amd_iommu_target_ivhd_type = get_highest_supported_ivhd_type(ivrs_base);
2583 	DUMP_printk("Using IVHD type %#x\n", amd_iommu_target_ivhd_type);
2584 
2585 	/*
2586 	 * First parse ACPI tables to find the largest Bus/Dev/Func
2587 	 * we need to handle. Upon this information the shared data
2588 	 * structures for the IOMMUs in the system will be allocated
2589 	 */
2590 	ret = find_last_devid_acpi(ivrs_base);
2591 	if (ret)
2592 		goto out;
2593 
2594 	dev_table_size     = tbl_size(DEV_TABLE_ENTRY_SIZE);
2595 	alias_table_size   = tbl_size(ALIAS_TABLE_ENTRY_SIZE);
2596 	rlookup_table_size = tbl_size(RLOOKUP_TABLE_ENTRY_SIZE);
2597 
2598 	/* Device table - directly used by all IOMMUs */
2599 	ret = -ENOMEM;
2600 	amd_iommu_dev_table = (void *)__get_free_pages(
2601 				      GFP_KERNEL | __GFP_ZERO | GFP_DMA32,
2602 				      get_order(dev_table_size));
2603 	if (amd_iommu_dev_table == NULL)
2604 		goto out;
2605 
2606 	/*
2607 	 * Alias table - map PCI Bus/Dev/Func to Bus/Dev/Func the
2608 	 * IOMMU see for that device
2609 	 */
2610 	amd_iommu_alias_table = (void *)__get_free_pages(GFP_KERNEL,
2611 			get_order(alias_table_size));
2612 	if (amd_iommu_alias_table == NULL)
2613 		goto out;
2614 
2615 	/* IOMMU rlookup table - find the IOMMU for a specific device */
2616 	amd_iommu_rlookup_table = (void *)__get_free_pages(
2617 			GFP_KERNEL | __GFP_ZERO,
2618 			get_order(rlookup_table_size));
2619 	if (amd_iommu_rlookup_table == NULL)
2620 		goto out;
2621 
2622 	amd_iommu_pd_alloc_bitmap = (void *)__get_free_pages(
2623 					    GFP_KERNEL | __GFP_ZERO,
2624 					    get_order(MAX_DOMAIN_ID/8));
2625 	if (amd_iommu_pd_alloc_bitmap == NULL)
2626 		goto out;
2627 
2628 	/*
2629 	 * let all alias entries point to itself
2630 	 */
2631 	for (i = 0; i <= amd_iommu_last_bdf; ++i)
2632 		amd_iommu_alias_table[i] = i;
2633 
2634 	/*
2635 	 * never allocate domain 0 because its used as the non-allocated and
2636 	 * error value placeholder
2637 	 */
2638 	__set_bit(0, amd_iommu_pd_alloc_bitmap);
2639 
2640 	/*
2641 	 * now the data structures are allocated and basically initialized
2642 	 * start the real acpi table scan
2643 	 */
2644 	ret = init_iommu_all(ivrs_base);
2645 	if (ret)
2646 		goto out;
2647 
2648 	/* Disable IOMMU if there's Stoney Ridge graphics */
2649 	for (i = 0; i < 32; i++) {
2650 		pci_id = read_pci_config(0, i, 0, 0);
2651 		if ((pci_id & 0xffff) == 0x1002 && (pci_id >> 16) == 0x98e4) {
2652 			pr_info("Disable IOMMU on Stoney Ridge\n");
2653 			amd_iommu_disabled = true;
2654 			break;
2655 		}
2656 	}
2657 
2658 	/* Disable any previously enabled IOMMUs */
2659 	if (!is_kdump_kernel() || amd_iommu_disabled)
2660 		disable_iommus();
2661 
2662 	if (amd_iommu_irq_remap)
2663 		amd_iommu_irq_remap = check_ioapic_information();
2664 
2665 	if (amd_iommu_irq_remap) {
2666 		/*
2667 		 * Interrupt remapping enabled, create kmem_cache for the
2668 		 * remapping tables.
2669 		 */
2670 		ret = -ENOMEM;
2671 		if (!AMD_IOMMU_GUEST_IR_GA(amd_iommu_guest_ir))
2672 			remap_cache_sz = MAX_IRQS_PER_TABLE * sizeof(u32);
2673 		else
2674 			remap_cache_sz = MAX_IRQS_PER_TABLE * (sizeof(u64) * 2);
2675 		amd_iommu_irq_cache = kmem_cache_create("irq_remap_cache",
2676 							remap_cache_sz,
2677 							IRQ_TABLE_ALIGNMENT,
2678 							0, NULL);
2679 		if (!amd_iommu_irq_cache)
2680 			goto out;
2681 
2682 		irq_lookup_table = (void *)__get_free_pages(
2683 				GFP_KERNEL | __GFP_ZERO,
2684 				get_order(rlookup_table_size));
2685 		kmemleak_alloc(irq_lookup_table, rlookup_table_size,
2686 			       1, GFP_KERNEL);
2687 		if (!irq_lookup_table)
2688 			goto out;
2689 	}
2690 
2691 	ret = init_memory_definitions(ivrs_base);
2692 	if (ret)
2693 		goto out;
2694 
2695 	/* init the device table */
2696 	init_device_table();
2697 
2698 out:
2699 	/* Don't leak any ACPI memory */
2700 	acpi_put_table(ivrs_base);
2701 	ivrs_base = NULL;
2702 
2703 	return ret;
2704 }
2705 
2706 static int amd_iommu_enable_interrupts(void)
2707 {
2708 	struct amd_iommu *iommu;
2709 	int ret = 0;
2710 
2711 	for_each_iommu(iommu) {
2712 		ret = iommu_init_msi(iommu);
2713 		if (ret)
2714 			goto out;
2715 	}
2716 
2717 out:
2718 	return ret;
2719 }
2720 
2721 static bool detect_ivrs(void)
2722 {
2723 	struct acpi_table_header *ivrs_base;
2724 	acpi_status status;
2725 
2726 	status = acpi_get_table("IVRS", 0, &ivrs_base);
2727 	if (status == AE_NOT_FOUND)
2728 		return false;
2729 	else if (ACPI_FAILURE(status)) {
2730 		const char *err = acpi_format_exception(status);
2731 		pr_err("IVRS table error: %s\n", err);
2732 		return false;
2733 	}
2734 
2735 	acpi_put_table(ivrs_base);
2736 
2737 	/* Make sure ACS will be enabled during PCI probe */
2738 	pci_request_acs();
2739 
2740 	return true;
2741 }
2742 
2743 /****************************************************************************
2744  *
2745  * AMD IOMMU Initialization State Machine
2746  *
2747  ****************************************************************************/
2748 
2749 static int __init state_next(void)
2750 {
2751 	int ret = 0;
2752 
2753 	switch (init_state) {
2754 	case IOMMU_START_STATE:
2755 		if (!detect_ivrs()) {
2756 			init_state	= IOMMU_NOT_FOUND;
2757 			ret		= -ENODEV;
2758 		} else {
2759 			init_state	= IOMMU_IVRS_DETECTED;
2760 		}
2761 		break;
2762 	case IOMMU_IVRS_DETECTED:
2763 		ret = early_amd_iommu_init();
2764 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
2765 		if (init_state == IOMMU_ACPI_FINISHED && amd_iommu_disabled) {
2766 			pr_info("AMD IOMMU disabled\n");
2767 			init_state = IOMMU_CMDLINE_DISABLED;
2768 			ret = -EINVAL;
2769 		}
2770 		break;
2771 	case IOMMU_ACPI_FINISHED:
2772 		early_enable_iommus();
2773 		x86_platform.iommu_shutdown = disable_iommus;
2774 		init_state = IOMMU_ENABLED;
2775 		break;
2776 	case IOMMU_ENABLED:
2777 		register_syscore_ops(&amd_iommu_syscore_ops);
2778 		ret = amd_iommu_init_pci();
2779 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_PCI_INIT;
2780 		enable_iommus_v2();
2781 		break;
2782 	case IOMMU_PCI_INIT:
2783 		ret = amd_iommu_enable_interrupts();
2784 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_INTERRUPTS_EN;
2785 		break;
2786 	case IOMMU_INTERRUPTS_EN:
2787 		ret = amd_iommu_init_dma_ops();
2788 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_DMA_OPS;
2789 		break;
2790 	case IOMMU_DMA_OPS:
2791 		init_state = IOMMU_INITIALIZED;
2792 		break;
2793 	case IOMMU_INITIALIZED:
2794 		/* Nothing to do */
2795 		break;
2796 	case IOMMU_NOT_FOUND:
2797 	case IOMMU_INIT_ERROR:
2798 	case IOMMU_CMDLINE_DISABLED:
2799 		/* Error states => do nothing */
2800 		ret = -EINVAL;
2801 		break;
2802 	default:
2803 		/* Unknown state */
2804 		BUG();
2805 	}
2806 
2807 	if (ret) {
2808 		free_dma_resources();
2809 		if (!irq_remapping_enabled) {
2810 			disable_iommus();
2811 			free_iommu_resources();
2812 		} else {
2813 			struct amd_iommu *iommu;
2814 
2815 			uninit_device_table_dma();
2816 			for_each_iommu(iommu)
2817 				iommu_flush_all_caches(iommu);
2818 		}
2819 	}
2820 	return ret;
2821 }
2822 
2823 static int __init iommu_go_to_state(enum iommu_init_state state)
2824 {
2825 	int ret = -EINVAL;
2826 
2827 	while (init_state != state) {
2828 		if (init_state == IOMMU_NOT_FOUND         ||
2829 		    init_state == IOMMU_INIT_ERROR        ||
2830 		    init_state == IOMMU_CMDLINE_DISABLED)
2831 			break;
2832 		ret = state_next();
2833 	}
2834 
2835 	return ret;
2836 }
2837 
2838 #ifdef CONFIG_IRQ_REMAP
2839 int __init amd_iommu_prepare(void)
2840 {
2841 	int ret;
2842 
2843 	amd_iommu_irq_remap = true;
2844 
2845 	ret = iommu_go_to_state(IOMMU_ACPI_FINISHED);
2846 	if (ret)
2847 		return ret;
2848 	return amd_iommu_irq_remap ? 0 : -ENODEV;
2849 }
2850 
2851 int __init amd_iommu_enable(void)
2852 {
2853 	int ret;
2854 
2855 	ret = iommu_go_to_state(IOMMU_ENABLED);
2856 	if (ret)
2857 		return ret;
2858 
2859 	irq_remapping_enabled = 1;
2860 	return amd_iommu_xt_mode;
2861 }
2862 
2863 void amd_iommu_disable(void)
2864 {
2865 	amd_iommu_suspend();
2866 }
2867 
2868 int amd_iommu_reenable(int mode)
2869 {
2870 	amd_iommu_resume();
2871 
2872 	return 0;
2873 }
2874 
2875 int __init amd_iommu_enable_faulting(void)
2876 {
2877 	/* We enable MSI later when PCI is initialized */
2878 	return 0;
2879 }
2880 #endif
2881 
2882 /*
2883  * This is the core init function for AMD IOMMU hardware in the system.
2884  * This function is called from the generic x86 DMA layer initialization
2885  * code.
2886  */
2887 static int __init amd_iommu_init(void)
2888 {
2889 	struct amd_iommu *iommu;
2890 	int ret;
2891 
2892 	ret = iommu_go_to_state(IOMMU_INITIALIZED);
2893 #ifdef CONFIG_GART_IOMMU
2894 	if (ret && list_empty(&amd_iommu_list)) {
2895 		/*
2896 		 * We failed to initialize the AMD IOMMU - try fallback
2897 		 * to GART if possible.
2898 		 */
2899 		gart_iommu_init();
2900 	}
2901 #endif
2902 
2903 	for_each_iommu(iommu)
2904 		amd_iommu_debugfs_setup(iommu);
2905 
2906 	return ret;
2907 }
2908 
2909 static bool amd_iommu_sme_check(void)
2910 {
2911 	if (!sme_active() || (boot_cpu_data.x86 != 0x17))
2912 		return true;
2913 
2914 	/* For Fam17h, a specific level of support is required */
2915 	if (boot_cpu_data.microcode >= 0x08001205)
2916 		return true;
2917 
2918 	if ((boot_cpu_data.microcode >= 0x08001126) &&
2919 	    (boot_cpu_data.microcode <= 0x080011ff))
2920 		return true;
2921 
2922 	pr_notice("IOMMU not currently supported when SME is active\n");
2923 
2924 	return false;
2925 }
2926 
2927 /****************************************************************************
2928  *
2929  * Early detect code. This code runs at IOMMU detection time in the DMA
2930  * layer. It just looks if there is an IVRS ACPI table to detect AMD
2931  * IOMMUs
2932  *
2933  ****************************************************************************/
2934 int __init amd_iommu_detect(void)
2935 {
2936 	int ret;
2937 
2938 	if (no_iommu || (iommu_detected && !gart_iommu_aperture))
2939 		return -ENODEV;
2940 
2941 	if (!amd_iommu_sme_check())
2942 		return -ENODEV;
2943 
2944 	ret = iommu_go_to_state(IOMMU_IVRS_DETECTED);
2945 	if (ret)
2946 		return ret;
2947 
2948 	amd_iommu_detected = true;
2949 	iommu_detected = 1;
2950 	x86_init.iommu.iommu_init = amd_iommu_init;
2951 
2952 	return 1;
2953 }
2954 
2955 /****************************************************************************
2956  *
2957  * Parsing functions for the AMD IOMMU specific kernel command line
2958  * options.
2959  *
2960  ****************************************************************************/
2961 
2962 static int __init parse_amd_iommu_dump(char *str)
2963 {
2964 	amd_iommu_dump = true;
2965 
2966 	return 1;
2967 }
2968 
2969 static int __init parse_amd_iommu_intr(char *str)
2970 {
2971 	for (; *str; ++str) {
2972 		if (strncmp(str, "legacy", 6) == 0) {
2973 			amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
2974 			break;
2975 		}
2976 		if (strncmp(str, "vapic", 5) == 0) {
2977 			amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_VAPIC;
2978 			break;
2979 		}
2980 	}
2981 	return 1;
2982 }
2983 
2984 static int __init parse_amd_iommu_options(char *str)
2985 {
2986 	for (; *str; ++str) {
2987 		if (strncmp(str, "fullflush", 9) == 0)
2988 			amd_iommu_unmap_flush = true;
2989 		if (strncmp(str, "off", 3) == 0)
2990 			amd_iommu_disabled = true;
2991 		if (strncmp(str, "force_isolation", 15) == 0)
2992 			amd_iommu_force_isolation = true;
2993 	}
2994 
2995 	return 1;
2996 }
2997 
2998 static int __init parse_ivrs_ioapic(char *str)
2999 {
3000 	unsigned int bus, dev, fn;
3001 	int ret, id, i;
3002 	u16 devid;
3003 
3004 	ret = sscanf(str, "[%d]=%x:%x.%x", &id, &bus, &dev, &fn);
3005 
3006 	if (ret != 4) {
3007 		pr_err("Invalid command line: ivrs_ioapic%s\n", str);
3008 		return 1;
3009 	}
3010 
3011 	if (early_ioapic_map_size == EARLY_MAP_SIZE) {
3012 		pr_err("Early IOAPIC map overflow - ignoring ivrs_ioapic%s\n",
3013 			str);
3014 		return 1;
3015 	}
3016 
3017 	devid = ((bus & 0xff) << 8) | ((dev & 0x1f) << 3) | (fn & 0x7);
3018 
3019 	cmdline_maps			= true;
3020 	i				= early_ioapic_map_size++;
3021 	early_ioapic_map[i].id		= id;
3022 	early_ioapic_map[i].devid	= devid;
3023 	early_ioapic_map[i].cmd_line	= true;
3024 
3025 	return 1;
3026 }
3027 
3028 static int __init parse_ivrs_hpet(char *str)
3029 {
3030 	unsigned int bus, dev, fn;
3031 	int ret, id, i;
3032 	u16 devid;
3033 
3034 	ret = sscanf(str, "[%d]=%x:%x.%x", &id, &bus, &dev, &fn);
3035 
3036 	if (ret != 4) {
3037 		pr_err("Invalid command line: ivrs_hpet%s\n", str);
3038 		return 1;
3039 	}
3040 
3041 	if (early_hpet_map_size == EARLY_MAP_SIZE) {
3042 		pr_err("Early HPET map overflow - ignoring ivrs_hpet%s\n",
3043 			str);
3044 		return 1;
3045 	}
3046 
3047 	devid = ((bus & 0xff) << 8) | ((dev & 0x1f) << 3) | (fn & 0x7);
3048 
3049 	cmdline_maps			= true;
3050 	i				= early_hpet_map_size++;
3051 	early_hpet_map[i].id		= id;
3052 	early_hpet_map[i].devid		= devid;
3053 	early_hpet_map[i].cmd_line	= true;
3054 
3055 	return 1;
3056 }
3057 
3058 static int __init parse_ivrs_acpihid(char *str)
3059 {
3060 	u32 bus, dev, fn;
3061 	char *hid, *uid, *p;
3062 	char acpiid[ACPIHID_UID_LEN + ACPIHID_HID_LEN] = {0};
3063 	int ret, i;
3064 
3065 	ret = sscanf(str, "[%x:%x.%x]=%s", &bus, &dev, &fn, acpiid);
3066 	if (ret != 4) {
3067 		pr_err("Invalid command line: ivrs_acpihid(%s)\n", str);
3068 		return 1;
3069 	}
3070 
3071 	p = acpiid;
3072 	hid = strsep(&p, ":");
3073 	uid = p;
3074 
3075 	if (!hid || !(*hid) || !uid) {
3076 		pr_err("Invalid command line: hid or uid\n");
3077 		return 1;
3078 	}
3079 
3080 	i = early_acpihid_map_size++;
3081 	memcpy(early_acpihid_map[i].hid, hid, strlen(hid));
3082 	memcpy(early_acpihid_map[i].uid, uid, strlen(uid));
3083 	early_acpihid_map[i].devid =
3084 		((bus & 0xff) << 8) | ((dev & 0x1f) << 3) | (fn & 0x7);
3085 	early_acpihid_map[i].cmd_line	= true;
3086 
3087 	return 1;
3088 }
3089 
3090 __setup("amd_iommu_dump",	parse_amd_iommu_dump);
3091 __setup("amd_iommu=",		parse_amd_iommu_options);
3092 __setup("amd_iommu_intr=",	parse_amd_iommu_intr);
3093 __setup("ivrs_ioapic",		parse_ivrs_ioapic);
3094 __setup("ivrs_hpet",		parse_ivrs_hpet);
3095 __setup("ivrs_acpihid",		parse_ivrs_acpihid);
3096 
3097 IOMMU_INIT_FINISH(amd_iommu_detect,
3098 		  gart_iommu_hole_init,
3099 		  NULL,
3100 		  NULL);
3101 
3102 bool amd_iommu_v2_supported(void)
3103 {
3104 	return amd_iommu_v2_present;
3105 }
3106 EXPORT_SYMBOL(amd_iommu_v2_supported);
3107 
3108 struct amd_iommu *get_amd_iommu(unsigned int idx)
3109 {
3110 	unsigned int i = 0;
3111 	struct amd_iommu *iommu;
3112 
3113 	for_each_iommu(iommu)
3114 		if (i++ == idx)
3115 			return iommu;
3116 	return NULL;
3117 }
3118 EXPORT_SYMBOL(get_amd_iommu);
3119 
3120 /****************************************************************************
3121  *
3122  * IOMMU EFR Performance Counter support functionality. This code allows
3123  * access to the IOMMU PC functionality.
3124  *
3125  ****************************************************************************/
3126 
3127 u8 amd_iommu_pc_get_max_banks(unsigned int idx)
3128 {
3129 	struct amd_iommu *iommu = get_amd_iommu(idx);
3130 
3131 	if (iommu)
3132 		return iommu->max_banks;
3133 
3134 	return 0;
3135 }
3136 EXPORT_SYMBOL(amd_iommu_pc_get_max_banks);
3137 
3138 bool amd_iommu_pc_supported(void)
3139 {
3140 	return amd_iommu_pc_present;
3141 }
3142 EXPORT_SYMBOL(amd_iommu_pc_supported);
3143 
3144 u8 amd_iommu_pc_get_max_counters(unsigned int idx)
3145 {
3146 	struct amd_iommu *iommu = get_amd_iommu(idx);
3147 
3148 	if (iommu)
3149 		return iommu->max_counters;
3150 
3151 	return 0;
3152 }
3153 EXPORT_SYMBOL(amd_iommu_pc_get_max_counters);
3154 
3155 static int iommu_pc_get_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr,
3156 				u8 fxn, u64 *value, bool is_write)
3157 {
3158 	u32 offset;
3159 	u32 max_offset_lim;
3160 
3161 	/* Make sure the IOMMU PC resource is available */
3162 	if (!amd_iommu_pc_present)
3163 		return -ENODEV;
3164 
3165 	/* Check for valid iommu and pc register indexing */
3166 	if (WARN_ON(!iommu || (fxn > 0x28) || (fxn & 7)))
3167 		return -ENODEV;
3168 
3169 	offset = (u32)(((0x40 | bank) << 12) | (cntr << 8) | fxn);
3170 
3171 	/* Limit the offset to the hw defined mmio region aperture */
3172 	max_offset_lim = (u32)(((0x40 | iommu->max_banks) << 12) |
3173 				(iommu->max_counters << 8) | 0x28);
3174 	if ((offset < MMIO_CNTR_REG_OFFSET) ||
3175 	    (offset > max_offset_lim))
3176 		return -EINVAL;
3177 
3178 	if (is_write) {
3179 		u64 val = *value & GENMASK_ULL(47, 0);
3180 
3181 		writel((u32)val, iommu->mmio_base + offset);
3182 		writel((val >> 32), iommu->mmio_base + offset + 4);
3183 	} else {
3184 		*value = readl(iommu->mmio_base + offset + 4);
3185 		*value <<= 32;
3186 		*value |= readl(iommu->mmio_base + offset);
3187 		*value &= GENMASK_ULL(47, 0);
3188 	}
3189 
3190 	return 0;
3191 }
3192 
3193 int amd_iommu_pc_get_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, u8 fxn, u64 *value)
3194 {
3195 	if (!iommu)
3196 		return -EINVAL;
3197 
3198 	return iommu_pc_get_set_reg(iommu, bank, cntr, fxn, value, false);
3199 }
3200 EXPORT_SYMBOL(amd_iommu_pc_get_reg);
3201 
3202 int amd_iommu_pc_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, u8 fxn, u64 *value)
3203 {
3204 	if (!iommu)
3205 		return -EINVAL;
3206 
3207 	return iommu_pc_get_set_reg(iommu, bank, cntr, fxn, value, true);
3208 }
3209 EXPORT_SYMBOL(amd_iommu_pc_set_reg);
3210