xref: /openbmc/linux/drivers/parisc/iosapic.c (revision 9470114d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 ** I/O Sapic Driver - PCI interrupt line support
4 **
5 **      (c) Copyright 1999 Grant Grundler
6 **      (c) Copyright 1999 Hewlett-Packard Company
7 **
8 **
9 ** The I/O sapic driver manages the Interrupt Redirection Table which is
10 ** the control logic to convert PCI line based interrupts into a Message
11 ** Signaled Interrupt (aka Transaction Based Interrupt, TBI).
12 **
13 ** Acronyms
14 ** --------
15 ** HPA  Hard Physical Address (aka MMIO address)
16 ** IRQ  Interrupt ReQuest. Implies Line based interrupt.
17 ** IRT	Interrupt Routing Table (provided by PAT firmware)
18 ** IRdT Interrupt Redirection Table. IRQ line to TXN ADDR/DATA
19 **      table which is implemented in I/O SAPIC.
20 ** ISR  Interrupt Service Routine. aka Interrupt handler.
21 ** MSI	Message Signaled Interrupt. PCI 2.2 functionality.
22 **      aka Transaction Based Interrupt (or TBI).
23 ** PA   Precision Architecture. HP's RISC architecture.
24 ** RISC Reduced Instruction Set Computer.
25 **
26 **
27 ** What's a Message Signalled Interrupt?
28 ** -------------------------------------
29 ** MSI is a write transaction which targets a processor and is similar
30 ** to a processor write to memory or MMIO. MSIs can be generated by I/O
31 ** devices as well as processors and require *architecture* to work.
32 **
33 ** PA only supports MSI. So I/O subsystems must either natively generate
34 ** MSIs (e.g. GSC or HP-PB) or convert line based interrupts into MSIs
35 ** (e.g. PCI and EISA).  IA64 supports MSIs via a "local SAPIC" which
36 ** acts on behalf of a processor.
37 **
38 ** MSI allows any I/O device to interrupt any processor. This makes
39 ** load balancing of the interrupt processing possible on an SMP platform.
40 ** Interrupts are also ordered WRT to DMA data.  It's possible on I/O
41 ** coherent systems to completely eliminate PIO reads from the interrupt
42 ** path. The device and driver must be designed and implemented to
43 ** guarantee all DMA has been issued (issues about atomicity here)
44 ** before the MSI is issued. I/O status can then safely be read from
45 ** DMA'd data by the ISR.
46 **
47 **
48 ** PA Firmware
49 ** -----------
50 ** PA-RISC platforms have two fundamentally different types of firmware.
51 ** For PCI devices, "Legacy" PDC initializes the "INTERRUPT_LINE" register
52 ** and BARs similar to a traditional PC BIOS.
53 ** The newer "PAT" firmware supports PDC calls which return tables.
54 ** PAT firmware only initializes the PCI Console and Boot interface.
55 ** With these tables, the OS can program all other PCI devices.
56 **
57 ** One such PAT PDC call returns the "Interrupt Routing Table" (IRT).
58 ** The IRT maps each PCI slot's INTA-D "output" line to an I/O SAPIC
59 ** input line.  If the IRT is not available, this driver assumes
60 ** INTERRUPT_LINE register has been programmed by firmware. The latter
61 ** case also means online addition of PCI cards can NOT be supported
62 ** even if HW support is present.
63 **
64 ** All platforms with PAT firmware to date (Oct 1999) use one Interrupt
65 ** Routing Table for the entire platform.
66 **
67 ** Where's the iosapic?
68 ** --------------------
69 ** I/O sapic is part of the "Core Electronics Complex". And on HP platforms
70 ** it's integrated as part of the PCI bus adapter, "lba".  So no bus walk
71 ** will discover I/O Sapic. I/O Sapic driver learns about each device
72 ** when lba driver advertises the presence of the I/O sapic by calling
73 ** iosapic_register().
74 **
75 **
76 ** IRQ handling notes
77 ** ------------------
78 ** The IO-SAPIC can indicate to the CPU which interrupt was asserted.
79 ** So, unlike the GSC-ASIC and Dino, we allocate one CPU interrupt per
80 ** IO-SAPIC interrupt and call the device driver's handler directly.
81 ** The IO-SAPIC driver hijacks the CPU interrupt handler so it can
82 ** issue the End Of Interrupt command to the IO-SAPIC.
83 **
84 ** Overview of exported iosapic functions
85 ** --------------------------------------
86 ** (caveat: code isn't finished yet - this is just the plan)
87 **
88 ** iosapic_init:
89 **   o initialize globals (lock, etc)
90 **   o try to read IRT. Presence of IRT determines if this is
91 **     a PAT platform or not.
92 **
93 ** iosapic_register():
94 **   o create iosapic_info instance data structure
95 **   o allocate vector_info array for this iosapic
96 **   o initialize vector_info - read corresponding IRdT?
97 **
98 ** iosapic_xlate_pin: (only called by fixup_irq for PAT platform)
99 **   o intr_pin = read cfg (INTERRUPT_PIN);
100 **   o if (device under PCI-PCI bridge)
101 **               translate slot/pin
102 **
103 ** iosapic_fixup_irq:
104 **   o if PAT platform (IRT present)
105 **	   intr_pin = iosapic_xlate_pin(isi,pcidev):
106 **         intr_line = find IRT entry(isi, PCI_SLOT(pcidev), intr_pin)
107 **         save IRT entry into vector_info later
108 **         write cfg INTERRUPT_LINE (with intr_line)?
109 **     else
110 **         intr_line = pcidev->irq
111 **         IRT pointer = NULL
112 **     endif
113 **   o locate vector_info (needs: isi, intr_line)
114 **   o allocate processor "irq" and get txn_addr/data
115 **   o request_irq(processor_irq,  iosapic_interrupt, vector_info,...)
116 **
117 ** iosapic_enable_irq:
118 **   o clear any pending IRQ on that line
119 **   o enable IRdT - call enable_irq(vector[line]->processor_irq)
120 **   o write EOI in case line is already asserted.
121 **
122 ** iosapic_disable_irq:
123 **   o disable IRdT - call disable_irq(vector[line]->processor_irq)
124 */
125 
126 #include <linux/pci.h>
127 
128 #include <asm/pdc.h>
129 #include <asm/pdcpat.h>
130 #ifdef CONFIG_SUPERIO
131 #include <asm/superio.h>
132 #endif
133 
134 #include <asm/ropes.h>
135 #include "iosapic_private.h"
136 
137 #define MODULE_NAME "iosapic"
138 
139 /* "local" compile flags */
140 #undef PCI_BRIDGE_FUNCS
141 #undef DEBUG_IOSAPIC
142 #undef DEBUG_IOSAPIC_IRT
143 
144 
145 #ifdef DEBUG_IOSAPIC
146 #define DBG(x...) printk(x)
147 #else /* DEBUG_IOSAPIC */
148 #define DBG(x...)
149 #endif /* DEBUG_IOSAPIC */
150 
151 #ifdef DEBUG_IOSAPIC_IRT
152 #define DBG_IRT(x...) printk(x)
153 #else
154 #define DBG_IRT(x...)
155 #endif
156 
157 #ifdef CONFIG_64BIT
158 #define COMPARE_IRTE_ADDR(irte, hpa)	((irte)->dest_iosapic_addr == (hpa))
159 #else
160 #define COMPARE_IRTE_ADDR(irte, hpa)	\
161 		((irte)->dest_iosapic_addr == ((hpa) | 0xffffffff00000000ULL))
162 #endif
163 
164 #define IOSAPIC_REG_SELECT              0x00
165 #define IOSAPIC_REG_WINDOW              0x10
166 #define IOSAPIC_REG_EOI                 0x40
167 
168 #define IOSAPIC_REG_VERSION		0x1
169 
170 #define IOSAPIC_IRDT_ENTRY(idx)		(0x10+(idx)*2)
171 #define IOSAPIC_IRDT_ENTRY_HI(idx)	(0x11+(idx)*2)
172 
173 static inline unsigned int iosapic_read(void __iomem *iosapic, unsigned int reg)
174 {
175 	writel(reg, iosapic + IOSAPIC_REG_SELECT);
176 	return readl(iosapic + IOSAPIC_REG_WINDOW);
177 }
178 
179 static inline void iosapic_write(void __iomem *iosapic, unsigned int reg, u32 val)
180 {
181 	writel(reg, iosapic + IOSAPIC_REG_SELECT);
182 	writel(val, iosapic + IOSAPIC_REG_WINDOW);
183 }
184 
185 #define IOSAPIC_VERSION_MASK	0x000000ff
186 #define	IOSAPIC_VERSION(ver)	((int) (ver & IOSAPIC_VERSION_MASK))
187 
188 #define IOSAPIC_MAX_ENTRY_MASK          0x00ff0000
189 #define IOSAPIC_MAX_ENTRY_SHIFT         0x10
190 #define	IOSAPIC_IRDT_MAX_ENTRY(ver)	\
191 	(int) (((ver) & IOSAPIC_MAX_ENTRY_MASK) >> IOSAPIC_MAX_ENTRY_SHIFT)
192 
193 /* bits in the "low" I/O Sapic IRdT entry */
194 #define IOSAPIC_IRDT_ENABLE       0x10000
195 #define IOSAPIC_IRDT_PO_LOW       0x02000
196 #define IOSAPIC_IRDT_LEVEL_TRIG   0x08000
197 #define IOSAPIC_IRDT_MODE_LPRI    0x00100
198 
199 /* bits in the "high" I/O Sapic IRdT entry */
200 #define IOSAPIC_IRDT_ID_EID_SHIFT              0x10
201 
202 
203 static DEFINE_SPINLOCK(iosapic_lock);
204 
205 static inline void iosapic_eoi(__le32 __iomem *addr, __le32 data)
206 {
207 	__raw_writel((__force u32)data, addr);
208 }
209 
210 /*
211 ** REVISIT: future platforms may have more than one IRT.
212 ** If so, the following three fields form a structure which
213 ** then be linked into a list. Names are chosen to make searching
214 ** for them easy - not necessarily accurate (eg "cell").
215 **
216 ** Alternative: iosapic_info could point to the IRT it's in.
217 ** iosapic_register() could search a list of IRT's.
218 */
219 static struct irt_entry *irt_cell;
220 static size_t irt_num_entry;
221 
222 static struct irt_entry *iosapic_alloc_irt(int num_entries)
223 {
224 	return kcalloc(num_entries, sizeof(struct irt_entry), GFP_KERNEL);
225 }
226 
227 /**
228  * iosapic_load_irt - Fill in the interrupt routing table
229  * @cell_num: The cell number of the CPU we're currently executing on
230  * @irt: The address to place the new IRT at
231  * @return The number of entries found
232  *
233  * The "Get PCI INT Routing Table Size" option returns the number of
234  * entries in the PCI interrupt routing table for the cell specified
235  * in the cell_number argument.  The cell number must be for a cell
236  * within the caller's protection domain.
237  *
238  * The "Get PCI INT Routing Table" option returns, for the cell
239  * specified in the cell_number argument, the PCI interrupt routing
240  * table in the caller allocated memory pointed to by mem_addr.
241  * We assume the IRT only contains entries for I/O SAPIC and
242  * calculate the size based on the size of I/O sapic entries.
243  *
244  * The PCI interrupt routing table entry format is derived from the
245  * IA64 SAL Specification 2.4.   The PCI interrupt routing table defines
246  * the routing of PCI interrupt signals between the PCI device output
247  * "pins" and the IO SAPICs' input "lines" (including core I/O PCI
248  * devices).  This table does NOT include information for devices/slots
249  * behind PCI to PCI bridges. See PCI to PCI Bridge Architecture Spec.
250  * for the architected method of routing of IRQ's behind PPB's.
251  */
252 
253 
254 static int __init
255 iosapic_load_irt(unsigned long cell_num, struct irt_entry **irt)
256 {
257 	long status;              /* PDC return value status */
258 	struct irt_entry *table;  /* start of interrupt routing tbl */
259 	unsigned long num_entries = 0UL;
260 
261 	BUG_ON(!irt);
262 
263 	if (is_pdc_pat()) {
264 		/* Use pat pdc routine to get interrupt routing table size */
265 		DBG("calling get_irt_size (cell %ld)\n", cell_num);
266 		status = pdc_pat_get_irt_size(&num_entries, cell_num);
267 		DBG("get_irt_size: %ld\n", status);
268 
269 		BUG_ON(status != PDC_OK);
270 		BUG_ON(num_entries == 0);
271 
272 		/*
273 		** allocate memory for interrupt routing table
274 		** This interface isn't really right. We are assuming
275 		** the contents of the table are exclusively
276 		** for I/O sapic devices.
277 		*/
278 		table = iosapic_alloc_irt(num_entries);
279 		if (table == NULL) {
280 			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
281 					"not alloc mem for IRT\n");
282 			return 0;
283 		}
284 
285 		/* get PCI INT routing table */
286 		status = pdc_pat_get_irt(table, cell_num);
287 		DBG("pdc_pat_get_irt: %ld\n", status);
288 		WARN_ON(status != PDC_OK);
289 	} else {
290 		/*
291 		** C3000/J5000 (and similar) platforms with Sprockets PDC
292 		** will return exactly one IRT for all iosapics.
293 		** So if we have one, don't need to get it again.
294 		*/
295 		if (irt_cell)
296 			return 0;
297 
298 		/* Should be using the Elroy's HPA, but it's ignored anyway */
299 		status = pdc_pci_irt_size(&num_entries, 0);
300 		DBG("pdc_pci_irt_size: %ld\n", status);
301 
302 		if (status != PDC_OK) {
303 			/* Not a "legacy" system with I/O SAPIC either */
304 			return 0;
305 		}
306 
307 		BUG_ON(num_entries == 0);
308 
309 		table = iosapic_alloc_irt(num_entries);
310 		if (!table) {
311 			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
312 					"not alloc mem for IRT\n");
313 			return 0;
314 		}
315 
316 		/* HPA ignored by this call too. */
317 		status = pdc_pci_irt(num_entries, 0, table);
318 		BUG_ON(status != PDC_OK);
319 	}
320 
321 	/* return interrupt table address */
322 	*irt = table;
323 
324 #ifdef DEBUG_IOSAPIC_IRT
325 {
326 	struct irt_entry *p = table;
327 	int i;
328 
329 	printk(MODULE_NAME " Interrupt Routing Table (cell %ld)\n", cell_num);
330 	printk(MODULE_NAME " start = 0x%p num_entries %ld entry_size %d\n",
331 		table,
332 		num_entries,
333 		(int) sizeof(struct irt_entry));
334 
335 	for (i = 0 ; i < num_entries ; i++, p++) {
336 		printk(MODULE_NAME " %02x %02x %02x %02x %02x %02x %02x %02x %08x%08x\n",
337 		p->entry_type, p->entry_length, p->interrupt_type,
338 		p->polarity_trigger, p->src_bus_irq_devno, p->src_bus_id,
339 		p->src_seg_id, p->dest_iosapic_intin,
340 		((u32 *) p)[2],
341 		((u32 *) p)[3]
342 		);
343 	}
344 }
345 #endif /* DEBUG_IOSAPIC_IRT */
346 
347 	return num_entries;
348 }
349 
350 
351 static int __init iosapic_init(void)
352 {
353 	unsigned long cell = 0;
354 
355 #ifdef __LP64__
356 	if (is_pdc_pat()) {
357 		int status;
358 		struct pdc_pat_cell_num cell_info;
359 
360 		status = pdc_pat_cell_get_number(&cell_info);
361 		if (status == PDC_OK) {
362 			cell = cell_info.cell_num;
363 		}
364 	}
365 #endif
366 
367 	/* get interrupt routing table for this cell */
368 	irt_num_entry = iosapic_load_irt(cell, &irt_cell);
369 	if (irt_num_entry == 0)
370 		irt_cell = NULL;	/* old PDC w/o iosapic */
371 
372 	return 0;
373 }
374 arch_initcall(iosapic_init);
375 
376 
377 /*
378 ** Return the IRT entry in case we need to look something else up.
379 */
380 static struct irt_entry *
381 irt_find_irqline(struct iosapic_info *isi, u8 slot, u8 intr_pin)
382 {
383 	struct irt_entry *i = irt_cell;
384 	int cnt;	/* track how many entries we've looked at */
385 	u8 irq_devno = (slot << IRT_DEV_SHIFT) | (intr_pin-1);
386 
387 	DBG_IRT("irt_find_irqline() SLOT %d pin %d\n", slot, intr_pin);
388 
389 	for (cnt=0; cnt < irt_num_entry; cnt++, i++) {
390 
391 		/*
392 		** Validate: entry_type, entry_length, interrupt_type
393 		**
394 		** Difference between validate vs compare is the former
395 		** should print debug info and is not expected to "fail"
396 		** on current platforms.
397 		*/
398 		if (i->entry_type != IRT_IOSAPIC_TYPE) {
399 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d type %d\n", i, cnt, i->entry_type);
400 			continue;
401 		}
402 
403 		if (i->entry_length != IRT_IOSAPIC_LENGTH) {
404 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d  length %d\n", i, cnt, i->entry_length);
405 			continue;
406 		}
407 
408 		if (i->interrupt_type != IRT_VECTORED_INTR) {
409 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry  %d interrupt_type %d\n", i, cnt, i->interrupt_type);
410 			continue;
411 		}
412 
413 		if (!COMPARE_IRTE_ADDR(i, isi->isi_hpa))
414 			continue;
415 
416 		if ((i->src_bus_irq_devno & IRT_IRQ_DEVNO_MASK) != irq_devno)
417 			continue;
418 
419 		/*
420 		** Ignore: src_bus_id and rc_seg_id correlate with
421 		**         iosapic_info->isi_hpa on HP platforms.
422 		**         If needed, pass in "PFA" (aka config space addr)
423 		**         instead of slot.
424 		*/
425 
426 		/* Found it! */
427 		return i;
428 	}
429 
430 	printk(KERN_WARNING MODULE_NAME ": 0x%lx : no IRT entry for slot %d, pin %d\n",
431 			isi->isi_hpa, slot, intr_pin);
432 	return NULL;
433 }
434 
435 
436 /*
437 ** xlate_pin() supports the skewing of IRQ lines done by subsidiary bridges.
438 ** Legacy PDC already does this translation for us and stores it in INTR_LINE.
439 **
440 ** PAT PDC needs to basically do what legacy PDC does:
441 ** o read PIN
442 ** o adjust PIN in case device is "behind" a PPB
443 **     (eg 4-port 100BT and SCSI/LAN "Combo Card")
444 ** o convert slot/pin to I/O SAPIC input line.
445 **
446 ** HP platforms only support:
447 ** o one level of skewing for any number of PPBs
448 ** o only support PCI-PCI Bridges.
449 */
450 static struct irt_entry *
451 iosapic_xlate_pin(struct iosapic_info *isi, struct pci_dev *pcidev)
452 {
453 	u8 intr_pin, intr_slot;
454 
455 	pci_read_config_byte(pcidev, PCI_INTERRUPT_PIN, &intr_pin);
456 
457 	DBG_IRT("iosapic_xlate_pin(%s) SLOT %d pin %d\n",
458 		pcidev->slot_name, PCI_SLOT(pcidev->devfn), intr_pin);
459 
460 	if (intr_pin == 0) {
461 		/* The device does NOT support/use IRQ lines.  */
462 		return NULL;
463 	}
464 
465 	/* Check if pcidev behind a PPB */
466 	if (pcidev->bus->parent) {
467 		/* Convert pcidev INTR_PIN into something we
468 		** can lookup in the IRT.
469 		*/
470 #ifdef PCI_BRIDGE_FUNCS
471 		/*
472 		** Proposal #1:
473 		**
474 		** call implementation specific translation function
475 		** This is architecturally "cleaner". HP-UX doesn't
476 		** support other secondary bus types (eg. E/ISA) directly.
477 		** May be needed for other processor (eg IA64) architectures
478 		** or by some ambitous soul who wants to watch TV.
479 		*/
480 		if (pci_bridge_funcs->xlate_intr_line) {
481 			intr_pin = pci_bridge_funcs->xlate_intr_line(pcidev);
482 		}
483 #else	/* PCI_BRIDGE_FUNCS */
484 		struct pci_bus *p = pcidev->bus;
485 		/*
486 		** Proposal #2:
487 		** The "pin" is skewed ((pin + dev - 1) % 4).
488 		**
489 		** This isn't very clean since I/O SAPIC must assume:
490 		**   - all platforms only have PCI busses.
491 		**   - only PCI-PCI bridge (eg not PCI-EISA, PCI-PCMCIA)
492 		**   - IRQ routing is only skewed once regardless of
493 		**     the number of PPB's between iosapic and device.
494 		**     (Bit3 expansion chassis follows this rule)
495 		**
496 		** Advantage is it's really easy to implement.
497 		*/
498 		intr_pin = pci_swizzle_interrupt_pin(pcidev, intr_pin);
499 #endif /* PCI_BRIDGE_FUNCS */
500 
501 		/*
502 		 * Locate the host slot of the PPB.
503 		 */
504 		while (p->parent->parent)
505 			p = p->parent;
506 
507 		intr_slot = PCI_SLOT(p->self->devfn);
508 	} else {
509 		intr_slot = PCI_SLOT(pcidev->devfn);
510 	}
511 	DBG_IRT("iosapic_xlate_pin:  bus %d slot %d pin %d\n",
512 			pcidev->bus->busn_res.start, intr_slot, intr_pin);
513 
514 	return irt_find_irqline(isi, intr_slot, intr_pin);
515 }
516 
517 static void iosapic_rd_irt_entry(struct vector_info *vi , u32 *dp0, u32 *dp1)
518 {
519 	struct iosapic_info *isp = vi->iosapic;
520 	u8 idx = vi->irqline;
521 
522 	*dp0 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY(idx));
523 	*dp1 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY_HI(idx));
524 }
525 
526 
527 static void iosapic_wr_irt_entry(struct vector_info *vi, u32 dp0, u32 dp1)
528 {
529 	struct iosapic_info *isp = vi->iosapic;
530 
531 	DBG_IRT("iosapic_wr_irt_entry(): irq %d hpa %lx 0x%x 0x%x\n",
532 		vi->irqline, isp->isi_hpa, dp0, dp1);
533 
534 	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY(vi->irqline), dp0);
535 
536 	/* Read the window register to flush the writes down to HW  */
537 	dp0 = readl(isp->addr+IOSAPIC_REG_WINDOW);
538 
539 	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY_HI(vi->irqline), dp1);
540 
541 	/* Read the window register to flush the writes down to HW  */
542 	dp1 = readl(isp->addr+IOSAPIC_REG_WINDOW);
543 }
544 
545 /*
546 ** set_irt prepares the data (dp0, dp1) according to the vector_info
547 ** and target cpu (id_eid).  dp0/dp1 are then used to program I/O SAPIC
548 ** IRdT for the given "vector" (aka IRQ line).
549 */
550 static void
551 iosapic_set_irt_data( struct vector_info *vi, u32 *dp0, u32 *dp1)
552 {
553 	u32 mode = 0;
554 	struct irt_entry *p = vi->irte;
555 
556 	if ((p->polarity_trigger & IRT_PO_MASK) == IRT_ACTIVE_LO)
557 		mode |= IOSAPIC_IRDT_PO_LOW;
558 
559 	if (((p->polarity_trigger >> IRT_EL_SHIFT) & IRT_EL_MASK) == IRT_LEVEL_TRIG)
560 		mode |= IOSAPIC_IRDT_LEVEL_TRIG;
561 
562 	/*
563 	** IA64 REVISIT
564 	** PA doesn't support EXTINT or LPRIO bits.
565 	*/
566 
567 	*dp0 = mode | (u32) vi->txn_data;
568 
569 	/*
570 	** Extracting id_eid isn't a real clean way of getting it.
571 	** But the encoding is the same for both PA and IA64 platforms.
572 	*/
573 	if (is_pdc_pat()) {
574 		/*
575 		** PAT PDC just hands it to us "right".
576 		** txn_addr comes from cpu_data[x].txn_addr.
577 		*/
578 		*dp1 = (u32) (vi->txn_addr);
579 	} else {
580 		/*
581 		** eg if base_addr == 0xfffa0000),
582 		**    we want to get 0xa0ff0000.
583 		**
584 		** eid	0x0ff00000 -> 0x00ff0000
585 		** id	0x000ff000 -> 0xff000000
586 		*/
587 		*dp1 = (((u32)vi->txn_addr & 0x0ff00000) >> 4) |
588 			(((u32)vi->txn_addr & 0x000ff000) << 12);
589 	}
590 	DBG_IRT("iosapic_set_irt_data(): 0x%x 0x%x\n", *dp0, *dp1);
591 }
592 
593 
594 static void iosapic_mask_irq(struct irq_data *d)
595 {
596 	unsigned long flags;
597 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
598 	u32 d0, d1;
599 
600 	spin_lock_irqsave(&iosapic_lock, flags);
601 	iosapic_rd_irt_entry(vi, &d0, &d1);
602 	d0 |= IOSAPIC_IRDT_ENABLE;
603 	iosapic_wr_irt_entry(vi, d0, d1);
604 	spin_unlock_irqrestore(&iosapic_lock, flags);
605 }
606 
607 static void iosapic_unmask_irq(struct irq_data *d)
608 {
609 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
610 	u32 d0, d1;
611 
612 	/* data is initialized by fixup_irq */
613 	WARN_ON(vi->txn_irq  == 0);
614 
615 	iosapic_set_irt_data(vi, &d0, &d1);
616 	iosapic_wr_irt_entry(vi, d0, d1);
617 
618 #ifdef DEBUG_IOSAPIC_IRT
619 {
620 	u32 *t = (u32 *) ((ulong) vi->eoi_addr & ~0xffUL);
621 	printk("iosapic_enable_irq(): regs %p", vi->eoi_addr);
622 	for ( ; t < vi->eoi_addr; t++)
623 		printk(" %x", readl(t));
624 	printk("\n");
625 }
626 
627 printk("iosapic_enable_irq(): sel ");
628 {
629 	struct iosapic_info *isp = vi->iosapic;
630 
631 	for (d0=0x10; d0<0x1e; d0++) {
632 		d1 = iosapic_read(isp->addr, d0);
633 		printk(" %x", d1);
634 	}
635 }
636 printk("\n");
637 #endif
638 
639 	/*
640 	 * Issuing I/O SAPIC an EOI causes an interrupt IFF IRQ line is
641 	 * asserted.  IRQ generally should not be asserted when a driver
642 	 * enables their IRQ. It can lead to "interesting" race conditions
643 	 * in the driver initialization sequence.
644 	 */
645 	DBG(KERN_DEBUG "enable_irq(%d): eoi(%p, 0x%x)\n", d->irq,
646 			vi->eoi_addr, vi->eoi_data);
647 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
648 }
649 
650 static void iosapic_eoi_irq(struct irq_data *d)
651 {
652 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
653 
654 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
655 	cpu_eoi_irq(d);
656 }
657 
658 #ifdef CONFIG_SMP
659 static int iosapic_set_affinity_irq(struct irq_data *d,
660 				    const struct cpumask *dest, bool force)
661 {
662 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
663 	u32 d0, d1, dummy_d0;
664 	unsigned long flags;
665 	int dest_cpu;
666 
667 	dest_cpu = cpu_check_affinity(d, dest);
668 	if (dest_cpu < 0)
669 		return -1;
670 
671 	irq_data_update_affinity(d, cpumask_of(dest_cpu));
672 	vi->txn_addr = txn_affinity_addr(d->irq, dest_cpu);
673 
674 	spin_lock_irqsave(&iosapic_lock, flags);
675 	/* d1 contains the destination CPU, so only want to set that
676 	 * entry */
677 	iosapic_rd_irt_entry(vi, &d0, &d1);
678 	iosapic_set_irt_data(vi, &dummy_d0, &d1);
679 	iosapic_wr_irt_entry(vi, d0, d1);
680 	spin_unlock_irqrestore(&iosapic_lock, flags);
681 
682 	return 0;
683 }
684 #endif
685 
686 static struct irq_chip iosapic_interrupt_type = {
687 	.name		=	"IO-SAPIC-level",
688 	.irq_unmask	=	iosapic_unmask_irq,
689 	.irq_mask	=	iosapic_mask_irq,
690 	.irq_ack	=	cpu_ack_irq,
691 	.irq_eoi	=	iosapic_eoi_irq,
692 #ifdef CONFIG_SMP
693 	.irq_set_affinity =	iosapic_set_affinity_irq,
694 #endif
695 };
696 
697 int iosapic_fixup_irq(void *isi_obj, struct pci_dev *pcidev)
698 {
699 	struct iosapic_info *isi = isi_obj;
700 	struct irt_entry *irte = NULL;  /* only used if PAT PDC */
701 	struct vector_info *vi;
702 	int isi_line;	/* line used by device */
703 
704 	if (!isi) {
705 		printk(KERN_WARNING MODULE_NAME ": hpa not registered for %s\n",
706 			pci_name(pcidev));
707 		return -1;
708 	}
709 
710 #ifdef CONFIG_SUPERIO
711 	/*
712 	 * HACK ALERT! (non-compliant PCI device support)
713 	 *
714 	 * All SuckyIO interrupts are routed through the PIC's on function 1.
715 	 * But SuckyIO OHCI USB controller gets an IRT entry anyway because
716 	 * it advertises INT D for INT_PIN.  Use that IRT entry to get the
717 	 * SuckyIO interrupt routing for PICs on function 1 (*BLEECCHH*).
718 	 */
719 	if (is_superio_device(pcidev)) {
720 		/* We must call superio_fixup_irq() to register the pdev */
721 		pcidev->irq = superio_fixup_irq(pcidev);
722 
723 		/* Don't return if need to program the IOSAPIC's IRT... */
724 		if (PCI_FUNC(pcidev->devfn) != SUPERIO_USB_FN)
725 			return pcidev->irq;
726 	}
727 #endif /* CONFIG_SUPERIO */
728 
729 	/* lookup IRT entry for isi/slot/pin set */
730 	irte = iosapic_xlate_pin(isi, pcidev);
731 	if (!irte) {
732 		printk("iosapic: no IRTE for %s (IRQ not connected?)\n",
733 				pci_name(pcidev));
734 		return -1;
735 	}
736 	DBG_IRT("iosapic_fixup_irq(): irte %p %x %x %x %x %x %x %x %x\n",
737 		irte,
738 		irte->entry_type,
739 		irte->entry_length,
740 		irte->polarity_trigger,
741 		irte->src_bus_irq_devno,
742 		irte->src_bus_id,
743 		irte->src_seg_id,
744 		irte->dest_iosapic_intin,
745 		(u32) irte->dest_iosapic_addr);
746 	isi_line = irte->dest_iosapic_intin;
747 
748 	/* get vector info for this input line */
749 	vi = isi->isi_vector + isi_line;
750 	DBG_IRT("iosapic_fixup_irq:  line %d vi 0x%p\n", isi_line, vi);
751 
752 	/* If this IRQ line has already been setup, skip it */
753 	if (vi->irte)
754 		goto out;
755 
756 	vi->irte = irte;
757 
758 	/*
759 	 * Allocate processor IRQ
760 	 *
761 	 * XXX/FIXME The txn_alloc_irq() code and related code should be
762 	 * moved to enable_irq(). That way we only allocate processor IRQ
763 	 * bits for devices that actually have drivers claiming them.
764 	 * Right now we assign an IRQ to every PCI device present,
765 	 * regardless of whether it's used or not.
766 	 */
767 	vi->txn_irq = txn_alloc_irq(8);
768 
769 	if (vi->txn_irq < 0)
770 		panic("I/O sapic: couldn't get TXN IRQ\n");
771 
772 	/* enable_irq() will use txn_* to program IRdT */
773 	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
774 	vi->txn_data = txn_alloc_data(vi->txn_irq);
775 
776 	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
777 	vi->eoi_data = cpu_to_le32(vi->txn_data);
778 
779 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
780 
781  out:
782 	pcidev->irq = vi->txn_irq;
783 
784 	DBG_IRT("iosapic_fixup_irq() %d:%d %x %x line %d irq %d\n",
785 		PCI_SLOT(pcidev->devfn), PCI_FUNC(pcidev->devfn),
786 		pcidev->vendor, pcidev->device, isi_line, pcidev->irq);
787 
788 	return pcidev->irq;
789 }
790 
791 static struct iosapic_info *iosapic_list;
792 
793 #ifdef CONFIG_64BIT
794 int iosapic_serial_irq(struct parisc_device *dev)
795 {
796 	struct iosapic_info *isi;
797 	struct irt_entry *irte;
798 	struct vector_info *vi;
799 	int cnt;
800 	int intin;
801 
802 	intin = (dev->mod_info >> 24) & 15;
803 
804 	/* lookup IRT entry for isi/slot/pin set */
805 	for (cnt = 0; cnt < irt_num_entry; cnt++) {
806 		irte = &irt_cell[cnt];
807 		if (COMPARE_IRTE_ADDR(irte, dev->mod0) &&
808 		    irte->dest_iosapic_intin == intin)
809 			break;
810 	}
811 	if (cnt >= irt_num_entry)
812 		return 0; /* no irq found, force polling */
813 
814 	DBG_IRT("iosapic_serial_irq(): irte %p %x %x %x %x %x %x %x %x\n",
815 		irte,
816 		irte->entry_type,
817 		irte->entry_length,
818 		irte->polarity_trigger,
819 		irte->src_bus_irq_devno,
820 		irte->src_bus_id,
821 		irte->src_seg_id,
822 		irte->dest_iosapic_intin,
823 		(u32) irte->dest_iosapic_addr);
824 
825 	/* search for iosapic */
826 	for (isi = iosapic_list; isi; isi = isi->isi_next)
827 		if (isi->isi_hpa == dev->mod0)
828 			break;
829 	if (!isi)
830 		return 0; /* no iosapic found, force polling */
831 
832 	/* get vector info for this input line */
833 	vi = isi->isi_vector + intin;
834 	DBG_IRT("iosapic_serial_irq:  line %d vi 0x%p\n", iosapic_intin, vi);
835 
836 	/* If this IRQ line has already been setup, skip it */
837 	if (vi->irte)
838 		goto out;
839 
840 	vi->irte = irte;
841 
842 	/*
843 	 * Allocate processor IRQ
844 	 *
845 	 * XXX/FIXME The txn_alloc_irq() code and related code should be
846 	 * moved to enable_irq(). That way we only allocate processor IRQ
847 	 * bits for devices that actually have drivers claiming them.
848 	 * Right now we assign an IRQ to every PCI device present,
849 	 * regardless of whether it's used or not.
850 	 */
851 	vi->txn_irq = txn_alloc_irq(8);
852 
853 	if (vi->txn_irq < 0)
854 		panic("I/O sapic: couldn't get TXN IRQ\n");
855 
856 	/* enable_irq() will use txn_* to program IRdT */
857 	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
858 	vi->txn_data = txn_alloc_data(vi->txn_irq);
859 
860 	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
861 	vi->eoi_data = cpu_to_le32(vi->txn_data);
862 
863 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
864 
865  out:
866 
867 	return vi->txn_irq;
868 }
869 EXPORT_SYMBOL(iosapic_serial_irq);
870 #endif
871 
872 
873 /*
874 ** squirrel away the I/O Sapic Version
875 */
876 static unsigned int
877 iosapic_rd_version(struct iosapic_info *isi)
878 {
879 	return iosapic_read(isi->addr, IOSAPIC_REG_VERSION);
880 }
881 
882 
883 /*
884 ** iosapic_register() is called by "drivers" with an integrated I/O SAPIC.
885 ** Caller must be certain they have an I/O SAPIC and know its MMIO address.
886 **
887 **	o allocate iosapic_info and add it to the list
888 **	o read iosapic version and squirrel that away
889 **	o read size of IRdT.
890 **	o allocate and initialize isi_vector[]
891 **	o allocate irq region
892 */
893 void *iosapic_register(unsigned long hpa, void __iomem *vaddr)
894 {
895 	struct iosapic_info *isi = NULL;
896 	struct irt_entry *irte = irt_cell;
897 	struct vector_info *vip;
898 	int cnt;	/* track how many entries we've looked at */
899 
900 	/*
901 	 * Astro based platforms can only support PCI OLARD if they implement
902 	 * PAT PDC.  Legacy PDC omits LBAs with no PCI devices from the IRT.
903 	 * Search the IRT and ignore iosapic's which aren't in the IRT.
904 	 */
905 	for (cnt=0; cnt < irt_num_entry; cnt++, irte++) {
906 		WARN_ON(IRT_IOSAPIC_TYPE != irte->entry_type);
907 		if (COMPARE_IRTE_ADDR(irte, hpa))
908 			break;
909 	}
910 
911 	if (cnt >= irt_num_entry) {
912 		DBG("iosapic_register() ignoring 0x%lx (NOT FOUND)\n", hpa);
913 		return NULL;
914 	}
915 
916 	isi = kzalloc(sizeof(struct iosapic_info), GFP_KERNEL);
917 	if (!isi) {
918 		BUG();
919 		return NULL;
920 	}
921 
922 	isi->addr = vaddr;
923 	isi->isi_hpa = hpa;
924 	isi->isi_version = iosapic_rd_version(isi);
925 	isi->isi_num_vectors = IOSAPIC_IRDT_MAX_ENTRY(isi->isi_version) + 1;
926 
927 	vip = isi->isi_vector = kcalloc(isi->isi_num_vectors,
928 					sizeof(struct vector_info), GFP_KERNEL);
929 	if (vip == NULL) {
930 		kfree(isi);
931 		return NULL;
932 	}
933 
934 	for (cnt=0; cnt < isi->isi_num_vectors; cnt++, vip++) {
935 		vip->irqline = (unsigned char) cnt;
936 		vip->iosapic = isi;
937 	}
938 	isi->isi_next = iosapic_list;
939 	iosapic_list = isi;
940 	return isi;
941 }
942 
943 
944 #ifdef DEBUG_IOSAPIC
945 
946 static void
947 iosapic_prt_irt(void *irt, long num_entry)
948 {
949 	unsigned int i, *irp = (unsigned int *) irt;
950 
951 
952 	printk(KERN_DEBUG MODULE_NAME ": Interrupt Routing Table (%lx entries)\n", num_entry);
953 
954 	for (i=0; i<num_entry; i++, irp += 4) {
955 		printk(KERN_DEBUG "%p : %2d %.8x %.8x %.8x %.8x\n",
956 					irp, i, irp[0], irp[1], irp[2], irp[3]);
957 	}
958 }
959 
960 
961 static void
962 iosapic_prt_vi(struct vector_info *vi)
963 {
964 	printk(KERN_DEBUG MODULE_NAME ": vector_info[%d] is at %p\n", vi->irqline, vi);
965 	printk(KERN_DEBUG "\t\tstatus:	 %.4x\n", vi->status);
966 	printk(KERN_DEBUG "\t\ttxn_irq:  %d\n",  vi->txn_irq);
967 	printk(KERN_DEBUG "\t\ttxn_addr: %lx\n", vi->txn_addr);
968 	printk(KERN_DEBUG "\t\ttxn_data: %lx\n", vi->txn_data);
969 	printk(KERN_DEBUG "\t\teoi_addr: %p\n",  vi->eoi_addr);
970 	printk(KERN_DEBUG "\t\teoi_data: %x\n",  vi->eoi_data);
971 }
972 
973 
974 static void
975 iosapic_prt_isi(struct iosapic_info *isi)
976 {
977 	printk(KERN_DEBUG MODULE_NAME ": io_sapic_info at %p\n", isi);
978 	printk(KERN_DEBUG "\t\tisi_hpa:       %lx\n", isi->isi_hpa);
979 	printk(KERN_DEBUG "\t\tisi_status:    %x\n", isi->isi_status);
980 	printk(KERN_DEBUG "\t\tisi_version:   %x\n", isi->isi_version);
981 	printk(KERN_DEBUG "\t\tisi_vector:    %p\n", isi->isi_vector);
982 }
983 #endif /* DEBUG_IOSAPIC */
984