xref: /openbmc/linux/drivers/parisc/iosapic.c (revision f9834f18)
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(void __iomem *addr, unsigned int data)
206 {
207 	__raw_writel(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 	unsigned long a;
225 
226 	/* The IRT needs to be 8-byte aligned for the PDC call.
227 	 * Normally kmalloc would guarantee larger alignment, but
228 	 * if CONFIG_DEBUG_SLAB is enabled, then we can get only
229 	 * 4-byte alignment on 32-bit kernels
230 	 */
231 	a = (unsigned long)kmalloc(sizeof(struct irt_entry) * num_entries + 8, GFP_KERNEL);
232 	a = (a + 7UL) & ~7UL;
233 	return (struct irt_entry *)a;
234 }
235 
236 /**
237  * iosapic_load_irt - Fill in the interrupt routing table
238  * @cell_num: The cell number of the CPU we're currently executing on
239  * @irt: The address to place the new IRT at
240  * @return The number of entries found
241  *
242  * The "Get PCI INT Routing Table Size" option returns the number of
243  * entries in the PCI interrupt routing table for the cell specified
244  * in the cell_number argument.  The cell number must be for a cell
245  * within the caller's protection domain.
246  *
247  * The "Get PCI INT Routing Table" option returns, for the cell
248  * specified in the cell_number argument, the PCI interrupt routing
249  * table in the caller allocated memory pointed to by mem_addr.
250  * We assume the IRT only contains entries for I/O SAPIC and
251  * calculate the size based on the size of I/O sapic entries.
252  *
253  * The PCI interrupt routing table entry format is derived from the
254  * IA64 SAL Specification 2.4.   The PCI interrupt routing table defines
255  * the routing of PCI interrupt signals between the PCI device output
256  * "pins" and the IO SAPICs' input "lines" (including core I/O PCI
257  * devices).  This table does NOT include information for devices/slots
258  * behind PCI to PCI bridges. See PCI to PCI Bridge Architecture Spec.
259  * for the architected method of routing of IRQ's behind PPB's.
260  */
261 
262 
263 static int __init
264 iosapic_load_irt(unsigned long cell_num, struct irt_entry **irt)
265 {
266 	long status;              /* PDC return value status */
267 	struct irt_entry *table;  /* start of interrupt routing tbl */
268 	unsigned long num_entries = 0UL;
269 
270 	BUG_ON(!irt);
271 
272 	if (is_pdc_pat()) {
273 		/* Use pat pdc routine to get interrupt routing table size */
274 		DBG("calling get_irt_size (cell %ld)\n", cell_num);
275 		status = pdc_pat_get_irt_size(&num_entries, cell_num);
276 		DBG("get_irt_size: %ld\n", status);
277 
278 		BUG_ON(status != PDC_OK);
279 		BUG_ON(num_entries == 0);
280 
281 		/*
282 		** allocate memory for interrupt routing table
283 		** This interface isn't really right. We are assuming
284 		** the contents of the table are exclusively
285 		** for I/O sapic devices.
286 		*/
287 		table = iosapic_alloc_irt(num_entries);
288 		if (table == NULL) {
289 			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
290 					"not alloc mem for IRT\n");
291 			return 0;
292 		}
293 
294 		/* get PCI INT routing table */
295 		status = pdc_pat_get_irt(table, cell_num);
296 		DBG("pdc_pat_get_irt: %ld\n", status);
297 		WARN_ON(status != PDC_OK);
298 	} else {
299 		/*
300 		** C3000/J5000 (and similar) platforms with Sprockets PDC
301 		** will return exactly one IRT for all iosapics.
302 		** So if we have one, don't need to get it again.
303 		*/
304 		if (irt_cell)
305 			return 0;
306 
307 		/* Should be using the Elroy's HPA, but it's ignored anyway */
308 		status = pdc_pci_irt_size(&num_entries, 0);
309 		DBG("pdc_pci_irt_size: %ld\n", status);
310 
311 		if (status != PDC_OK) {
312 			/* Not a "legacy" system with I/O SAPIC either */
313 			return 0;
314 		}
315 
316 		BUG_ON(num_entries == 0);
317 
318 		table = iosapic_alloc_irt(num_entries);
319 		if (!table) {
320 			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
321 					"not alloc mem for IRT\n");
322 			return 0;
323 		}
324 
325 		/* HPA ignored by this call too. */
326 		status = pdc_pci_irt(num_entries, 0, table);
327 		BUG_ON(status != PDC_OK);
328 	}
329 
330 	/* return interrupt table address */
331 	*irt = table;
332 
333 #ifdef DEBUG_IOSAPIC_IRT
334 {
335 	struct irt_entry *p = table;
336 	int i;
337 
338 	printk(MODULE_NAME " Interrupt Routing Table (cell %ld)\n", cell_num);
339 	printk(MODULE_NAME " start = 0x%p num_entries %ld entry_size %d\n",
340 		table,
341 		num_entries,
342 		(int) sizeof(struct irt_entry));
343 
344 	for (i = 0 ; i < num_entries ; i++, p++) {
345 		printk(MODULE_NAME " %02x %02x %02x %02x %02x %02x %02x %02x %08x%08x\n",
346 		p->entry_type, p->entry_length, p->interrupt_type,
347 		p->polarity_trigger, p->src_bus_irq_devno, p->src_bus_id,
348 		p->src_seg_id, p->dest_iosapic_intin,
349 		((u32 *) p)[2],
350 		((u32 *) p)[3]
351 		);
352 	}
353 }
354 #endif /* DEBUG_IOSAPIC_IRT */
355 
356 	return num_entries;
357 }
358 
359 
360 
361 void __init iosapic_init(void)
362 {
363 	unsigned long cell = 0;
364 
365 	DBG("iosapic_init()\n");
366 
367 #ifdef __LP64__
368 	if (is_pdc_pat()) {
369 		int status;
370 		struct pdc_pat_cell_num cell_info;
371 
372 		status = pdc_pat_cell_get_number(&cell_info);
373 		if (status == PDC_OK) {
374 			cell = cell_info.cell_num;
375 		}
376 	}
377 #endif
378 
379 	/* get interrupt routing table for this cell */
380 	irt_num_entry = iosapic_load_irt(cell, &irt_cell);
381 	if (irt_num_entry == 0)
382 		irt_cell = NULL;	/* old PDC w/o iosapic */
383 }
384 
385 
386 /*
387 ** Return the IRT entry in case we need to look something else up.
388 */
389 static struct irt_entry *
390 irt_find_irqline(struct iosapic_info *isi, u8 slot, u8 intr_pin)
391 {
392 	struct irt_entry *i = irt_cell;
393 	int cnt;	/* track how many entries we've looked at */
394 	u8 irq_devno = (slot << IRT_DEV_SHIFT) | (intr_pin-1);
395 
396 	DBG_IRT("irt_find_irqline() SLOT %d pin %d\n", slot, intr_pin);
397 
398 	for (cnt=0; cnt < irt_num_entry; cnt++, i++) {
399 
400 		/*
401 		** Validate: entry_type, entry_length, interrupt_type
402 		**
403 		** Difference between validate vs compare is the former
404 		** should print debug info and is not expected to "fail"
405 		** on current platforms.
406 		*/
407 		if (i->entry_type != IRT_IOSAPIC_TYPE) {
408 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d type %d\n", i, cnt, i->entry_type);
409 			continue;
410 		}
411 
412 		if (i->entry_length != IRT_IOSAPIC_LENGTH) {
413 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d  length %d\n", i, cnt, i->entry_length);
414 			continue;
415 		}
416 
417 		if (i->interrupt_type != IRT_VECTORED_INTR) {
418 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry  %d interrupt_type %d\n", i, cnt, i->interrupt_type);
419 			continue;
420 		}
421 
422 		if (!COMPARE_IRTE_ADDR(i, isi->isi_hpa))
423 			continue;
424 
425 		if ((i->src_bus_irq_devno & IRT_IRQ_DEVNO_MASK) != irq_devno)
426 			continue;
427 
428 		/*
429 		** Ignore: src_bus_id and rc_seg_id correlate with
430 		**         iosapic_info->isi_hpa on HP platforms.
431 		**         If needed, pass in "PFA" (aka config space addr)
432 		**         instead of slot.
433 		*/
434 
435 		/* Found it! */
436 		return i;
437 	}
438 
439 	printk(KERN_WARNING MODULE_NAME ": 0x%lx : no IRT entry for slot %d, pin %d\n",
440 			isi->isi_hpa, slot, intr_pin);
441 	return NULL;
442 }
443 
444 
445 /*
446 ** xlate_pin() supports the skewing of IRQ lines done by subsidiary bridges.
447 ** Legacy PDC already does this translation for us and stores it in INTR_LINE.
448 **
449 ** PAT PDC needs to basically do what legacy PDC does:
450 ** o read PIN
451 ** o adjust PIN in case device is "behind" a PPB
452 **     (eg 4-port 100BT and SCSI/LAN "Combo Card")
453 ** o convert slot/pin to I/O SAPIC input line.
454 **
455 ** HP platforms only support:
456 ** o one level of skewing for any number of PPBs
457 ** o only support PCI-PCI Bridges.
458 */
459 static struct irt_entry *
460 iosapic_xlate_pin(struct iosapic_info *isi, struct pci_dev *pcidev)
461 {
462 	u8 intr_pin, intr_slot;
463 
464 	pci_read_config_byte(pcidev, PCI_INTERRUPT_PIN, &intr_pin);
465 
466 	DBG_IRT("iosapic_xlate_pin(%s) SLOT %d pin %d\n",
467 		pcidev->slot_name, PCI_SLOT(pcidev->devfn), intr_pin);
468 
469 	if (intr_pin == 0) {
470 		/* The device does NOT support/use IRQ lines.  */
471 		return NULL;
472 	}
473 
474 	/* Check if pcidev behind a PPB */
475 	if (pcidev->bus->parent) {
476 		/* Convert pcidev INTR_PIN into something we
477 		** can lookup in the IRT.
478 		*/
479 #ifdef PCI_BRIDGE_FUNCS
480 		/*
481 		** Proposal #1:
482 		**
483 		** call implementation specific translation function
484 		** This is architecturally "cleaner". HP-UX doesn't
485 		** support other secondary bus types (eg. E/ISA) directly.
486 		** May be needed for other processor (eg IA64) architectures
487 		** or by some ambitous soul who wants to watch TV.
488 		*/
489 		if (pci_bridge_funcs->xlate_intr_line) {
490 			intr_pin = pci_bridge_funcs->xlate_intr_line(pcidev);
491 		}
492 #else	/* PCI_BRIDGE_FUNCS */
493 		struct pci_bus *p = pcidev->bus;
494 		/*
495 		** Proposal #2:
496 		** The "pin" is skewed ((pin + dev - 1) % 4).
497 		**
498 		** This isn't very clean since I/O SAPIC must assume:
499 		**   - all platforms only have PCI busses.
500 		**   - only PCI-PCI bridge (eg not PCI-EISA, PCI-PCMCIA)
501 		**   - IRQ routing is only skewed once regardless of
502 		**     the number of PPB's between iosapic and device.
503 		**     (Bit3 expansion chassis follows this rule)
504 		**
505 		** Advantage is it's really easy to implement.
506 		*/
507 		intr_pin = pci_swizzle_interrupt_pin(pcidev, intr_pin);
508 #endif /* PCI_BRIDGE_FUNCS */
509 
510 		/*
511 		 * Locate the host slot of the PPB.
512 		 */
513 		while (p->parent->parent)
514 			p = p->parent;
515 
516 		intr_slot = PCI_SLOT(p->self->devfn);
517 	} else {
518 		intr_slot = PCI_SLOT(pcidev->devfn);
519 	}
520 	DBG_IRT("iosapic_xlate_pin:  bus %d slot %d pin %d\n",
521 			pcidev->bus->busn_res.start, intr_slot, intr_pin);
522 
523 	return irt_find_irqline(isi, intr_slot, intr_pin);
524 }
525 
526 static void iosapic_rd_irt_entry(struct vector_info *vi , u32 *dp0, u32 *dp1)
527 {
528 	struct iosapic_info *isp = vi->iosapic;
529 	u8 idx = vi->irqline;
530 
531 	*dp0 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY(idx));
532 	*dp1 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY_HI(idx));
533 }
534 
535 
536 static void iosapic_wr_irt_entry(struct vector_info *vi, u32 dp0, u32 dp1)
537 {
538 	struct iosapic_info *isp = vi->iosapic;
539 
540 	DBG_IRT("iosapic_wr_irt_entry(): irq %d hpa %lx 0x%x 0x%x\n",
541 		vi->irqline, isp->isi_hpa, dp0, dp1);
542 
543 	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY(vi->irqline), dp0);
544 
545 	/* Read the window register to flush the writes down to HW  */
546 	dp0 = readl(isp->addr+IOSAPIC_REG_WINDOW);
547 
548 	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY_HI(vi->irqline), dp1);
549 
550 	/* Read the window register to flush the writes down to HW  */
551 	dp1 = readl(isp->addr+IOSAPIC_REG_WINDOW);
552 }
553 
554 /*
555 ** set_irt prepares the data (dp0, dp1) according to the vector_info
556 ** and target cpu (id_eid).  dp0/dp1 are then used to program I/O SAPIC
557 ** IRdT for the given "vector" (aka IRQ line).
558 */
559 static void
560 iosapic_set_irt_data( struct vector_info *vi, u32 *dp0, u32 *dp1)
561 {
562 	u32 mode = 0;
563 	struct irt_entry *p = vi->irte;
564 
565 	if ((p->polarity_trigger & IRT_PO_MASK) == IRT_ACTIVE_LO)
566 		mode |= IOSAPIC_IRDT_PO_LOW;
567 
568 	if (((p->polarity_trigger >> IRT_EL_SHIFT) & IRT_EL_MASK) == IRT_LEVEL_TRIG)
569 		mode |= IOSAPIC_IRDT_LEVEL_TRIG;
570 
571 	/*
572 	** IA64 REVISIT
573 	** PA doesn't support EXTINT or LPRIO bits.
574 	*/
575 
576 	*dp0 = mode | (u32) vi->txn_data;
577 
578 	/*
579 	** Extracting id_eid isn't a real clean way of getting it.
580 	** But the encoding is the same for both PA and IA64 platforms.
581 	*/
582 	if (is_pdc_pat()) {
583 		/*
584 		** PAT PDC just hands it to us "right".
585 		** txn_addr comes from cpu_data[x].txn_addr.
586 		*/
587 		*dp1 = (u32) (vi->txn_addr);
588 	} else {
589 		/*
590 		** eg if base_addr == 0xfffa0000),
591 		**    we want to get 0xa0ff0000.
592 		**
593 		** eid	0x0ff00000 -> 0x00ff0000
594 		** id	0x000ff000 -> 0xff000000
595 		*/
596 		*dp1 = (((u32)vi->txn_addr & 0x0ff00000) >> 4) |
597 			(((u32)vi->txn_addr & 0x000ff000) << 12);
598 	}
599 	DBG_IRT("iosapic_set_irt_data(): 0x%x 0x%x\n", *dp0, *dp1);
600 }
601 
602 
603 static void iosapic_mask_irq(struct irq_data *d)
604 {
605 	unsigned long flags;
606 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
607 	u32 d0, d1;
608 
609 	spin_lock_irqsave(&iosapic_lock, flags);
610 	iosapic_rd_irt_entry(vi, &d0, &d1);
611 	d0 |= IOSAPIC_IRDT_ENABLE;
612 	iosapic_wr_irt_entry(vi, d0, d1);
613 	spin_unlock_irqrestore(&iosapic_lock, flags);
614 }
615 
616 static void iosapic_unmask_irq(struct irq_data *d)
617 {
618 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
619 	u32 d0, d1;
620 
621 	/* data is initialized by fixup_irq */
622 	WARN_ON(vi->txn_irq  == 0);
623 
624 	iosapic_set_irt_data(vi, &d0, &d1);
625 	iosapic_wr_irt_entry(vi, d0, d1);
626 
627 #ifdef DEBUG_IOSAPIC_IRT
628 {
629 	u32 *t = (u32 *) ((ulong) vi->eoi_addr & ~0xffUL);
630 	printk("iosapic_enable_irq(): regs %p", vi->eoi_addr);
631 	for ( ; t < vi->eoi_addr; t++)
632 		printk(" %x", readl(t));
633 	printk("\n");
634 }
635 
636 printk("iosapic_enable_irq(): sel ");
637 {
638 	struct iosapic_info *isp = vi->iosapic;
639 
640 	for (d0=0x10; d0<0x1e; d0++) {
641 		d1 = iosapic_read(isp->addr, d0);
642 		printk(" %x", d1);
643 	}
644 }
645 printk("\n");
646 #endif
647 
648 	/*
649 	 * Issuing I/O SAPIC an EOI causes an interrupt IFF IRQ line is
650 	 * asserted.  IRQ generally should not be asserted when a driver
651 	 * enables their IRQ. It can lead to "interesting" race conditions
652 	 * in the driver initialization sequence.
653 	 */
654 	DBG(KERN_DEBUG "enable_irq(%d): eoi(%p, 0x%x)\n", d->irq,
655 			vi->eoi_addr, vi->eoi_data);
656 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
657 }
658 
659 static void iosapic_eoi_irq(struct irq_data *d)
660 {
661 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
662 
663 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
664 	cpu_eoi_irq(d);
665 }
666 
667 #ifdef CONFIG_SMP
668 static int iosapic_set_affinity_irq(struct irq_data *d,
669 				    const struct cpumask *dest, bool force)
670 {
671 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
672 	u32 d0, d1, dummy_d0;
673 	unsigned long flags;
674 	int dest_cpu;
675 
676 	dest_cpu = cpu_check_affinity(d, dest);
677 	if (dest_cpu < 0)
678 		return -1;
679 
680 	cpumask_copy(irq_data_get_affinity_mask(d), cpumask_of(dest_cpu));
681 	vi->txn_addr = txn_affinity_addr(d->irq, dest_cpu);
682 
683 	spin_lock_irqsave(&iosapic_lock, flags);
684 	/* d1 contains the destination CPU, so only want to set that
685 	 * entry */
686 	iosapic_rd_irt_entry(vi, &d0, &d1);
687 	iosapic_set_irt_data(vi, &dummy_d0, &d1);
688 	iosapic_wr_irt_entry(vi, d0, d1);
689 	spin_unlock_irqrestore(&iosapic_lock, flags);
690 
691 	return 0;
692 }
693 #endif
694 
695 static struct irq_chip iosapic_interrupt_type = {
696 	.name		=	"IO-SAPIC-level",
697 	.irq_unmask	=	iosapic_unmask_irq,
698 	.irq_mask	=	iosapic_mask_irq,
699 	.irq_ack	=	cpu_ack_irq,
700 	.irq_eoi	=	iosapic_eoi_irq,
701 #ifdef CONFIG_SMP
702 	.irq_set_affinity =	iosapic_set_affinity_irq,
703 #endif
704 };
705 
706 int iosapic_fixup_irq(void *isi_obj, struct pci_dev *pcidev)
707 {
708 	struct iosapic_info *isi = isi_obj;
709 	struct irt_entry *irte = NULL;  /* only used if PAT PDC */
710 	struct vector_info *vi;
711 	int isi_line;	/* line used by device */
712 
713 	if (!isi) {
714 		printk(KERN_WARNING MODULE_NAME ": hpa not registered for %s\n",
715 			pci_name(pcidev));
716 		return -1;
717 	}
718 
719 #ifdef CONFIG_SUPERIO
720 	/*
721 	 * HACK ALERT! (non-compliant PCI device support)
722 	 *
723 	 * All SuckyIO interrupts are routed through the PIC's on function 1.
724 	 * But SuckyIO OHCI USB controller gets an IRT entry anyway because
725 	 * it advertises INT D for INT_PIN.  Use that IRT entry to get the
726 	 * SuckyIO interrupt routing for PICs on function 1 (*BLEECCHH*).
727 	 */
728 	if (is_superio_device(pcidev)) {
729 		/* We must call superio_fixup_irq() to register the pdev */
730 		pcidev->irq = superio_fixup_irq(pcidev);
731 
732 		/* Don't return if need to program the IOSAPIC's IRT... */
733 		if (PCI_FUNC(pcidev->devfn) != SUPERIO_USB_FN)
734 			return pcidev->irq;
735 	}
736 #endif /* CONFIG_SUPERIO */
737 
738 	/* lookup IRT entry for isi/slot/pin set */
739 	irte = iosapic_xlate_pin(isi, pcidev);
740 	if (!irte) {
741 		printk("iosapic: no IRTE for %s (IRQ not connected?)\n",
742 				pci_name(pcidev));
743 		return -1;
744 	}
745 	DBG_IRT("iosapic_fixup_irq(): irte %p %x %x %x %x %x %x %x %x\n",
746 		irte,
747 		irte->entry_type,
748 		irte->entry_length,
749 		irte->polarity_trigger,
750 		irte->src_bus_irq_devno,
751 		irte->src_bus_id,
752 		irte->src_seg_id,
753 		irte->dest_iosapic_intin,
754 		(u32) irte->dest_iosapic_addr);
755 	isi_line = irte->dest_iosapic_intin;
756 
757 	/* get vector info for this input line */
758 	vi = isi->isi_vector + isi_line;
759 	DBG_IRT("iosapic_fixup_irq:  line %d vi 0x%p\n", isi_line, vi);
760 
761 	/* If this IRQ line has already been setup, skip it */
762 	if (vi->irte)
763 		goto out;
764 
765 	vi->irte = irte;
766 
767 	/*
768 	 * Allocate processor IRQ
769 	 *
770 	 * XXX/FIXME The txn_alloc_irq() code and related code should be
771 	 * moved to enable_irq(). That way we only allocate processor IRQ
772 	 * bits for devices that actually have drivers claiming them.
773 	 * Right now we assign an IRQ to every PCI device present,
774 	 * regardless of whether it's used or not.
775 	 */
776 	vi->txn_irq = txn_alloc_irq(8);
777 
778 	if (vi->txn_irq < 0)
779 		panic("I/O sapic: couldn't get TXN IRQ\n");
780 
781 	/* enable_irq() will use txn_* to program IRdT */
782 	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
783 	vi->txn_data = txn_alloc_data(vi->txn_irq);
784 
785 	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
786 	vi->eoi_data = cpu_to_le32(vi->txn_data);
787 
788 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
789 
790  out:
791 	pcidev->irq = vi->txn_irq;
792 
793 	DBG_IRT("iosapic_fixup_irq() %d:%d %x %x line %d irq %d\n",
794 		PCI_SLOT(pcidev->devfn), PCI_FUNC(pcidev->devfn),
795 		pcidev->vendor, pcidev->device, isi_line, pcidev->irq);
796 
797 	return pcidev->irq;
798 }
799 
800 static struct iosapic_info *iosapic_list;
801 
802 #ifdef CONFIG_64BIT
803 int iosapic_serial_irq(struct parisc_device *dev)
804 {
805 	struct iosapic_info *isi;
806 	struct irt_entry *irte;
807 	struct vector_info *vi;
808 	int cnt;
809 	int intin;
810 
811 	intin = (dev->mod_info >> 24) & 15;
812 
813 	/* lookup IRT entry for isi/slot/pin set */
814 	for (cnt = 0; cnt < irt_num_entry; cnt++) {
815 		irte = &irt_cell[cnt];
816 		if (COMPARE_IRTE_ADDR(irte, dev->mod0) &&
817 		    irte->dest_iosapic_intin == intin)
818 			break;
819 	}
820 	if (cnt >= irt_num_entry)
821 		return 0; /* no irq found, force polling */
822 
823 	DBG_IRT("iosapic_serial_irq(): irte %p %x %x %x %x %x %x %x %x\n",
824 		irte,
825 		irte->entry_type,
826 		irte->entry_length,
827 		irte->polarity_trigger,
828 		irte->src_bus_irq_devno,
829 		irte->src_bus_id,
830 		irte->src_seg_id,
831 		irte->dest_iosapic_intin,
832 		(u32) irte->dest_iosapic_addr);
833 
834 	/* search for iosapic */
835 	for (isi = iosapic_list; isi; isi = isi->isi_next)
836 		if (isi->isi_hpa == dev->mod0)
837 			break;
838 	if (!isi)
839 		return 0; /* no iosapic found, force polling */
840 
841 	/* get vector info for this input line */
842 	vi = isi->isi_vector + intin;
843 	DBG_IRT("iosapic_serial_irq:  line %d vi 0x%p\n", iosapic_intin, vi);
844 
845 	/* If this IRQ line has already been setup, skip it */
846 	if (vi->irte)
847 		goto out;
848 
849 	vi->irte = irte;
850 
851 	/*
852 	 * Allocate processor IRQ
853 	 *
854 	 * XXX/FIXME The txn_alloc_irq() code and related code should be
855 	 * moved to enable_irq(). That way we only allocate processor IRQ
856 	 * bits for devices that actually have drivers claiming them.
857 	 * Right now we assign an IRQ to every PCI device present,
858 	 * regardless of whether it's used or not.
859 	 */
860 	vi->txn_irq = txn_alloc_irq(8);
861 
862 	if (vi->txn_irq < 0)
863 		panic("I/O sapic: couldn't get TXN IRQ\n");
864 
865 	/* enable_irq() will use txn_* to program IRdT */
866 	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
867 	vi->txn_data = txn_alloc_data(vi->txn_irq);
868 
869 	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
870 	vi->eoi_data = cpu_to_le32(vi->txn_data);
871 
872 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
873 
874  out:
875 
876 	return vi->txn_irq;
877 }
878 #endif
879 
880 
881 /*
882 ** squirrel away the I/O Sapic Version
883 */
884 static unsigned int
885 iosapic_rd_version(struct iosapic_info *isi)
886 {
887 	return iosapic_read(isi->addr, IOSAPIC_REG_VERSION);
888 }
889 
890 
891 /*
892 ** iosapic_register() is called by "drivers" with an integrated I/O SAPIC.
893 ** Caller must be certain they have an I/O SAPIC and know its MMIO address.
894 **
895 **	o allocate iosapic_info and add it to the list
896 **	o read iosapic version and squirrel that away
897 **	o read size of IRdT.
898 **	o allocate and initialize isi_vector[]
899 **	o allocate irq region
900 */
901 void *iosapic_register(unsigned long hpa)
902 {
903 	struct iosapic_info *isi = NULL;
904 	struct irt_entry *irte = irt_cell;
905 	struct vector_info *vip;
906 	int cnt;	/* track how many entries we've looked at */
907 
908 	/*
909 	 * Astro based platforms can only support PCI OLARD if they implement
910 	 * PAT PDC.  Legacy PDC omits LBAs with no PCI devices from the IRT.
911 	 * Search the IRT and ignore iosapic's which aren't in the IRT.
912 	 */
913 	for (cnt=0; cnt < irt_num_entry; cnt++, irte++) {
914 		WARN_ON(IRT_IOSAPIC_TYPE != irte->entry_type);
915 		if (COMPARE_IRTE_ADDR(irte, hpa))
916 			break;
917 	}
918 
919 	if (cnt >= irt_num_entry) {
920 		DBG("iosapic_register() ignoring 0x%lx (NOT FOUND)\n", hpa);
921 		return NULL;
922 	}
923 
924 	isi = kzalloc(sizeof(struct iosapic_info), GFP_KERNEL);
925 	if (!isi) {
926 		BUG();
927 		return NULL;
928 	}
929 
930 	isi->addr = ioremap(hpa, 4096);
931 	isi->isi_hpa = hpa;
932 	isi->isi_version = iosapic_rd_version(isi);
933 	isi->isi_num_vectors = IOSAPIC_IRDT_MAX_ENTRY(isi->isi_version) + 1;
934 
935 	vip = isi->isi_vector = kcalloc(isi->isi_num_vectors,
936 					sizeof(struct vector_info), GFP_KERNEL);
937 	if (vip == NULL) {
938 		kfree(isi);
939 		return NULL;
940 	}
941 
942 	for (cnt=0; cnt < isi->isi_num_vectors; cnt++, vip++) {
943 		vip->irqline = (unsigned char) cnt;
944 		vip->iosapic = isi;
945 	}
946 	isi->isi_next = iosapic_list;
947 	iosapic_list = isi;
948 	return isi;
949 }
950 
951 
952 #ifdef DEBUG_IOSAPIC
953 
954 static void
955 iosapic_prt_irt(void *irt, long num_entry)
956 {
957 	unsigned int i, *irp = (unsigned int *) irt;
958 
959 
960 	printk(KERN_DEBUG MODULE_NAME ": Interrupt Routing Table (%lx entries)\n", num_entry);
961 
962 	for (i=0; i<num_entry; i++, irp += 4) {
963 		printk(KERN_DEBUG "%p : %2d %.8x %.8x %.8x %.8x\n",
964 					irp, i, irp[0], irp[1], irp[2], irp[3]);
965 	}
966 }
967 
968 
969 static void
970 iosapic_prt_vi(struct vector_info *vi)
971 {
972 	printk(KERN_DEBUG MODULE_NAME ": vector_info[%d] is at %p\n", vi->irqline, vi);
973 	printk(KERN_DEBUG "\t\tstatus:	 %.4x\n", vi->status);
974 	printk(KERN_DEBUG "\t\ttxn_irq:  %d\n",  vi->txn_irq);
975 	printk(KERN_DEBUG "\t\ttxn_addr: %lx\n", vi->txn_addr);
976 	printk(KERN_DEBUG "\t\ttxn_data: %lx\n", vi->txn_data);
977 	printk(KERN_DEBUG "\t\teoi_addr: %p\n",  vi->eoi_addr);
978 	printk(KERN_DEBUG "\t\teoi_data: %x\n",  vi->eoi_data);
979 }
980 
981 
982 static void
983 iosapic_prt_isi(struct iosapic_info *isi)
984 {
985 	printk(KERN_DEBUG MODULE_NAME ": io_sapic_info at %p\n", isi);
986 	printk(KERN_DEBUG "\t\tisi_hpa:       %lx\n", isi->isi_hpa);
987 	printk(KERN_DEBUG "\t\tisi_status:    %x\n", isi->isi_status);
988 	printk(KERN_DEBUG "\t\tisi_version:   %x\n", isi->isi_version);
989 	printk(KERN_DEBUG "\t\tisi_vector:    %p\n", isi->isi_vector);
990 }
991 #endif /* DEBUG_IOSAPIC */
992