• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2 ** I/O Sapic Driver - PCI interrupt line support
3 **
4 **      (c) Copyright 1999 Grant Grundler
5 **      (c) Copyright 1999 Hewlett-Packard Company
6 **
7 **      This program is free software; you can redistribute it and/or modify
8 **      it under the terms of the GNU General Public License as published by
9 **      the Free Software Foundation; either version 2 of the License, or
10 **      (at your option) any later version.
11 **
12 ** The I/O sapic driver manages the Interrupt Redirection Table which is
13 ** the control logic to convert PCI line based interrupts into a Message
14 ** Signaled Interrupt (aka Transaction Based Interrupt, TBI).
15 **
16 ** Acronyms
17 ** --------
18 ** HPA  Hard Physical Address (aka MMIO address)
19 ** IRQ  Interrupt ReQuest. Implies Line based interrupt.
20 ** IRT	Interrupt Routing Table (provided by PAT firmware)
21 ** IRdT Interrupt Redirection Table. IRQ line to TXN ADDR/DATA
22 **      table which is implemented in I/O SAPIC.
23 ** ISR  Interrupt Service Routine. aka Interrupt handler.
24 ** MSI	Message Signaled Interrupt. PCI 2.2 functionality.
25 **      aka Transaction Based Interrupt (or TBI).
26 ** PA   Precision Architecture. HP's RISC architecture.
27 ** RISC Reduced Instruction Set Computer.
28 **
29 **
30 ** What's a Message Signalled Interrupt?
31 ** -------------------------------------
32 ** MSI is a write transaction which targets a processor and is similar
33 ** to a processor write to memory or MMIO. MSIs can be generated by I/O
34 ** devices as well as processors and require *architecture* to work.
35 **
36 ** PA only supports MSI. So I/O subsystems must either natively generate
37 ** MSIs (e.g. GSC or HP-PB) or convert line based interrupts into MSIs
38 ** (e.g. PCI and EISA).  IA64 supports MSIs via a "local SAPIC" which
39 ** acts on behalf of a processor.
40 **
41 ** MSI allows any I/O device to interrupt any processor. This makes
42 ** load balancing of the interrupt processing possible on an SMP platform.
43 ** Interrupts are also ordered WRT to DMA data.  It's possible on I/O
44 ** coherent systems to completely eliminate PIO reads from the interrupt
45 ** path. The device and driver must be designed and implemented to
46 ** guarantee all DMA has been issued (issues about atomicity here)
47 ** before the MSI is issued. I/O status can then safely be read from
48 ** DMA'd data by the ISR.
49 **
50 **
51 ** PA Firmware
52 ** -----------
53 ** PA-RISC platforms have two fundamentally different types of firmware.
54 ** For PCI devices, "Legacy" PDC initializes the "INTERRUPT_LINE" register
55 ** and BARs similar to a traditional PC BIOS.
56 ** The newer "PAT" firmware supports PDC calls which return tables.
57 ** PAT firmware only initializes the PCI Console and Boot interface.
58 ** With these tables, the OS can program all other PCI devices.
59 **
60 ** One such PAT PDC call returns the "Interrupt Routing Table" (IRT).
61 ** The IRT maps each PCI slot's INTA-D "output" line to an I/O SAPIC
62 ** input line.  If the IRT is not available, this driver assumes
63 ** INTERRUPT_LINE register has been programmed by firmware. The latter
64 ** case also means online addition of PCI cards can NOT be supported
65 ** even if HW support is present.
66 **
67 ** All platforms with PAT firmware to date (Oct 1999) use one Interrupt
68 ** Routing Table for the entire platform.
69 **
70 ** Where's the iosapic?
71 ** --------------------
72 ** I/O sapic is part of the "Core Electronics Complex". And on HP platforms
73 ** it's integrated as part of the PCI bus adapter, "lba".  So no bus walk
74 ** will discover I/O Sapic. I/O Sapic driver learns about each device
75 ** when lba driver advertises the presence of the I/O sapic by calling
76 ** iosapic_register().
77 **
78 **
79 ** IRQ handling notes
80 ** ------------------
81 ** The IO-SAPIC can indicate to the CPU which interrupt was asserted.
82 ** So, unlike the GSC-ASIC and Dino, we allocate one CPU interrupt per
83 ** IO-SAPIC interrupt and call the device driver's handler directly.
84 ** The IO-SAPIC driver hijacks the CPU interrupt handler so it can
85 ** issue the End Of Interrupt command to the IO-SAPIC.
86 **
87 ** Overview of exported iosapic functions
88 ** --------------------------------------
89 ** (caveat: code isn't finished yet - this is just the plan)
90 **
91 ** iosapic_init:
92 **   o initialize globals (lock, etc)
93 **   o try to read IRT. Presence of IRT determines if this is
94 **     a PAT platform or not.
95 **
96 ** iosapic_register():
97 **   o create iosapic_info instance data structure
98 **   o allocate vector_info array for this iosapic
99 **   o initialize vector_info - read corresponding IRdT?
100 **
101 ** iosapic_xlate_pin: (only called by fixup_irq for PAT platform)
102 **   o intr_pin = read cfg (INTERRUPT_PIN);
103 **   o if (device under PCI-PCI bridge)
104 **               translate slot/pin
105 **
106 ** iosapic_fixup_irq:
107 **   o if PAT platform (IRT present)
108 **	   intr_pin = iosapic_xlate_pin(isi,pcidev):
109 **         intr_line = find IRT entry(isi, PCI_SLOT(pcidev), intr_pin)
110 **         save IRT entry into vector_info later
111 **         write cfg INTERRUPT_LINE (with intr_line)?
112 **     else
113 **         intr_line = pcidev->irq
114 **         IRT pointer = NULL
115 **     endif
116 **   o locate vector_info (needs: isi, intr_line)
117 **   o allocate processor "irq" and get txn_addr/data
118 **   o request_irq(processor_irq,  iosapic_interrupt, vector_info,...)
119 **
120 ** iosapic_enable_irq:
121 **   o clear any pending IRQ on that line
122 **   o enable IRdT - call enable_irq(vector[line]->processor_irq)
123 **   o write EOI in case line is already asserted.
124 **
125 ** iosapic_disable_irq:
126 **   o disable IRdT - call disable_irq(vector[line]->processor_irq)
127 */
128 
129 
130 /* FIXME: determine which include files are really needed */
131 #include <linux/types.h>
132 #include <linux/kernel.h>
133 #include <linux/spinlock.h>
134 #include <linux/pci.h>
135 #include <linux/init.h>
136 #include <linux/slab.h>
137 #include <linux/interrupt.h>
138 
139 #include <asm/byteorder.h>	/* get in-line asm for swab */
140 #include <asm/pdc.h>
141 #include <asm/pdcpat.h>
142 #include <asm/page.h>
143 #include <asm/io.h>		/* read/write functions */
144 #ifdef CONFIG_SUPERIO
145 #include <asm/superio.h>
146 #endif
147 
148 #include <asm/ropes.h>
149 #include "iosapic_private.h"
150 
151 #define MODULE_NAME "iosapic"
152 
153 /* "local" compile flags */
154 #undef PCI_BRIDGE_FUNCS
155 #undef DEBUG_IOSAPIC
156 #undef DEBUG_IOSAPIC_IRT
157 
158 
159 #ifdef DEBUG_IOSAPIC
160 #define DBG(x...) printk(x)
161 #else /* DEBUG_IOSAPIC */
162 #define DBG(x...)
163 #endif /* DEBUG_IOSAPIC */
164 
165 #ifdef DEBUG_IOSAPIC_IRT
166 #define DBG_IRT(x...) printk(x)
167 #else
168 #define DBG_IRT(x...)
169 #endif
170 
171 #ifdef CONFIG_64BIT
172 #define COMPARE_IRTE_ADDR(irte, hpa)	((irte)->dest_iosapic_addr == (hpa))
173 #else
174 #define COMPARE_IRTE_ADDR(irte, hpa)	\
175 		((irte)->dest_iosapic_addr == ((hpa) | 0xffffffff00000000ULL))
176 #endif
177 
178 #define IOSAPIC_REG_SELECT              0x00
179 #define IOSAPIC_REG_WINDOW              0x10
180 #define IOSAPIC_REG_EOI                 0x40
181 
182 #define IOSAPIC_REG_VERSION		0x1
183 
184 #define IOSAPIC_IRDT_ENTRY(idx)		(0x10+(idx)*2)
185 #define IOSAPIC_IRDT_ENTRY_HI(idx)	(0x11+(idx)*2)
186 
iosapic_read(void __iomem * iosapic,unsigned int reg)187 static inline unsigned int iosapic_read(void __iomem *iosapic, unsigned int reg)
188 {
189 	writel(reg, iosapic + IOSAPIC_REG_SELECT);
190 	return readl(iosapic + IOSAPIC_REG_WINDOW);
191 }
192 
iosapic_write(void __iomem * iosapic,unsigned int reg,u32 val)193 static inline void iosapic_write(void __iomem *iosapic, unsigned int reg, u32 val)
194 {
195 	writel(reg, iosapic + IOSAPIC_REG_SELECT);
196 	writel(val, iosapic + IOSAPIC_REG_WINDOW);
197 }
198 
199 #define IOSAPIC_VERSION_MASK	0x000000ff
200 #define	IOSAPIC_VERSION(ver)	((int) (ver & IOSAPIC_VERSION_MASK))
201 
202 #define IOSAPIC_MAX_ENTRY_MASK          0x00ff0000
203 #define IOSAPIC_MAX_ENTRY_SHIFT         0x10
204 #define	IOSAPIC_IRDT_MAX_ENTRY(ver)	\
205 	(int) (((ver) & IOSAPIC_MAX_ENTRY_MASK) >> IOSAPIC_MAX_ENTRY_SHIFT)
206 
207 /* bits in the "low" I/O Sapic IRdT entry */
208 #define IOSAPIC_IRDT_ENABLE       0x10000
209 #define IOSAPIC_IRDT_PO_LOW       0x02000
210 #define IOSAPIC_IRDT_LEVEL_TRIG   0x08000
211 #define IOSAPIC_IRDT_MODE_LPRI    0x00100
212 
213 /* bits in the "high" I/O Sapic IRdT entry */
214 #define IOSAPIC_IRDT_ID_EID_SHIFT              0x10
215 
216 
217 static DEFINE_SPINLOCK(iosapic_lock);
218 
iosapic_eoi(void __iomem * addr,unsigned int data)219 static inline void iosapic_eoi(void __iomem *addr, unsigned int data)
220 {
221 	__raw_writel(data, addr);
222 }
223 
224 /*
225 ** REVISIT: future platforms may have more than one IRT.
226 ** If so, the following three fields form a structure which
227 ** then be linked into a list. Names are chosen to make searching
228 ** for them easy - not necessarily accurate (eg "cell").
229 **
230 ** Alternative: iosapic_info could point to the IRT it's in.
231 ** iosapic_register() could search a list of IRT's.
232 */
233 static struct irt_entry *irt_cell;
234 static size_t irt_num_entry;
235 
iosapic_alloc_irt(int num_entries)236 static struct irt_entry *iosapic_alloc_irt(int num_entries)
237 {
238 	unsigned long a;
239 
240 	/* The IRT needs to be 8-byte aligned for the PDC call.
241 	 * Normally kmalloc would guarantee larger alignment, but
242 	 * if CONFIG_DEBUG_SLAB is enabled, then we can get only
243 	 * 4-byte alignment on 32-bit kernels
244 	 */
245 	a = (unsigned long)kmalloc(sizeof(struct irt_entry) * num_entries + 8, GFP_KERNEL);
246 	a = (a + 7UL) & ~7UL;
247 	return (struct irt_entry *)a;
248 }
249 
250 /**
251  * iosapic_load_irt - Fill in the interrupt routing table
252  * @cell_num: The cell number of the CPU we're currently executing on
253  * @irt: The address to place the new IRT at
254  * @return The number of entries found
255  *
256  * The "Get PCI INT Routing Table Size" option returns the number of
257  * entries in the PCI interrupt routing table for the cell specified
258  * in the cell_number argument.  The cell number must be for a cell
259  * within the caller's protection domain.
260  *
261  * The "Get PCI INT Routing Table" option returns, for the cell
262  * specified in the cell_number argument, the PCI interrupt routing
263  * table in the caller allocated memory pointed to by mem_addr.
264  * We assume the IRT only contains entries for I/O SAPIC and
265  * calculate the size based on the size of I/O sapic entries.
266  *
267  * The PCI interrupt routing table entry format is derived from the
268  * IA64 SAL Specification 2.4.   The PCI interrupt routing table defines
269  * the routing of PCI interrupt signals between the PCI device output
270  * "pins" and the IO SAPICs' input "lines" (including core I/O PCI
271  * devices).  This table does NOT include information for devices/slots
272  * behind PCI to PCI bridges. See PCI to PCI Bridge Architecture Spec.
273  * for the architected method of routing of IRQ's behind PPB's.
274  */
275 
276 
277 static int __init
iosapic_load_irt(unsigned long cell_num,struct irt_entry ** irt)278 iosapic_load_irt(unsigned long cell_num, struct irt_entry **irt)
279 {
280 	long status;              /* PDC return value status */
281 	struct irt_entry *table;  /* start of interrupt routing tbl */
282 	unsigned long num_entries = 0UL;
283 
284 	BUG_ON(!irt);
285 
286 	if (is_pdc_pat()) {
287 		/* Use pat pdc routine to get interrupt routing table size */
288 		DBG("calling get_irt_size (cell %ld)\n", cell_num);
289 		status = pdc_pat_get_irt_size(&num_entries, cell_num);
290 		DBG("get_irt_size: %ld\n", status);
291 
292 		BUG_ON(status != PDC_OK);
293 		BUG_ON(num_entries == 0);
294 
295 		/*
296 		** allocate memory for interrupt routing table
297 		** This interface isn't really right. We are assuming
298 		** the contents of the table are exclusively
299 		** for I/O sapic devices.
300 		*/
301 		table = iosapic_alloc_irt(num_entries);
302 		if (table == NULL) {
303 			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
304 					"not alloc mem for IRT\n");
305 			return 0;
306 		}
307 
308 		/* get PCI INT routing table */
309 		status = pdc_pat_get_irt(table, cell_num);
310 		DBG("pdc_pat_get_irt: %ld\n", status);
311 		WARN_ON(status != PDC_OK);
312 	} else {
313 		/*
314 		** C3000/J5000 (and similar) platforms with Sprockets PDC
315 		** will return exactly one IRT for all iosapics.
316 		** So if we have one, don't need to get it again.
317 		*/
318 		if (irt_cell)
319 			return 0;
320 
321 		/* Should be using the Elroy's HPA, but it's ignored anyway */
322 		status = pdc_pci_irt_size(&num_entries, 0);
323 		DBG("pdc_pci_irt_size: %ld\n", status);
324 
325 		if (status != PDC_OK) {
326 			/* Not a "legacy" system with I/O SAPIC either */
327 			return 0;
328 		}
329 
330 		BUG_ON(num_entries == 0);
331 
332 		table = iosapic_alloc_irt(num_entries);
333 		if (!table) {
334 			printk(KERN_WARNING MODULE_NAME ": read_irt : can "
335 					"not alloc mem for IRT\n");
336 			return 0;
337 		}
338 
339 		/* HPA ignored by this call too. */
340 		status = pdc_pci_irt(num_entries, 0, table);
341 		BUG_ON(status != PDC_OK);
342 	}
343 
344 	/* return interrupt table address */
345 	*irt = table;
346 
347 #ifdef DEBUG_IOSAPIC_IRT
348 {
349 	struct irt_entry *p = table;
350 	int i;
351 
352 	printk(MODULE_NAME " Interrupt Routing Table (cell %ld)\n", cell_num);
353 	printk(MODULE_NAME " start = 0x%p num_entries %ld entry_size %d\n",
354 		table,
355 		num_entries,
356 		(int) sizeof(struct irt_entry));
357 
358 	for (i = 0 ; i < num_entries ; i++, p++) {
359 		printk(MODULE_NAME " %02x %02x %02x %02x %02x %02x %02x %02x %08x%08x\n",
360 		p->entry_type, p->entry_length, p->interrupt_type,
361 		p->polarity_trigger, p->src_bus_irq_devno, p->src_bus_id,
362 		p->src_seg_id, p->dest_iosapic_intin,
363 		((u32 *) p)[2],
364 		((u32 *) p)[3]
365 		);
366 	}
367 }
368 #endif /* DEBUG_IOSAPIC_IRT */
369 
370 	return num_entries;
371 }
372 
373 
374 
iosapic_init(void)375 void __init iosapic_init(void)
376 {
377 	unsigned long cell = 0;
378 
379 	DBG("iosapic_init()\n");
380 
381 #ifdef __LP64__
382 	if (is_pdc_pat()) {
383 		int status;
384 		struct pdc_pat_cell_num cell_info;
385 
386 		status = pdc_pat_cell_get_number(&cell_info);
387 		if (status == PDC_OK) {
388 			cell = cell_info.cell_num;
389 		}
390 	}
391 #endif
392 
393 	/* get interrupt routing table for this cell */
394 	irt_num_entry = iosapic_load_irt(cell, &irt_cell);
395 	if (irt_num_entry == 0)
396 		irt_cell = NULL;	/* old PDC w/o iosapic */
397 }
398 
399 
400 /*
401 ** Return the IRT entry in case we need to look something else up.
402 */
403 static struct irt_entry *
irt_find_irqline(struct iosapic_info * isi,u8 slot,u8 intr_pin)404 irt_find_irqline(struct iosapic_info *isi, u8 slot, u8 intr_pin)
405 {
406 	struct irt_entry *i = irt_cell;
407 	int cnt;	/* track how many entries we've looked at */
408 	u8 irq_devno = (slot << IRT_DEV_SHIFT) | (intr_pin-1);
409 
410 	DBG_IRT("irt_find_irqline() SLOT %d pin %d\n", slot, intr_pin);
411 
412 	for (cnt=0; cnt < irt_num_entry; cnt++, i++) {
413 
414 		/*
415 		** Validate: entry_type, entry_length, interrupt_type
416 		**
417 		** Difference between validate vs compare is the former
418 		** should print debug info and is not expected to "fail"
419 		** on current platforms.
420 		*/
421 		if (i->entry_type != IRT_IOSAPIC_TYPE) {
422 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d type %d\n", i, cnt, i->entry_type);
423 			continue;
424 		}
425 
426 		if (i->entry_length != IRT_IOSAPIC_LENGTH) {
427 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry %d  length %d\n", i, cnt, i->entry_length);
428 			continue;
429 		}
430 
431 		if (i->interrupt_type != IRT_VECTORED_INTR) {
432 			DBG_IRT(KERN_WARNING MODULE_NAME ":find_irqline(0x%p): skipping entry  %d interrupt_type %d\n", i, cnt, i->interrupt_type);
433 			continue;
434 		}
435 
436 		if (!COMPARE_IRTE_ADDR(i, isi->isi_hpa))
437 			continue;
438 
439 		if ((i->src_bus_irq_devno & IRT_IRQ_DEVNO_MASK) != irq_devno)
440 			continue;
441 
442 		/*
443 		** Ignore: src_bus_id and rc_seg_id correlate with
444 		**         iosapic_info->isi_hpa on HP platforms.
445 		**         If needed, pass in "PFA" (aka config space addr)
446 		**         instead of slot.
447 		*/
448 
449 		/* Found it! */
450 		return i;
451 	}
452 
453 	printk(KERN_WARNING MODULE_NAME ": 0x%lx : no IRT entry for slot %d, pin %d\n",
454 			isi->isi_hpa, slot, intr_pin);
455 	return NULL;
456 }
457 
458 
459 /*
460 ** xlate_pin() supports the skewing of IRQ lines done by subsidiary bridges.
461 ** Legacy PDC already does this translation for us and stores it in INTR_LINE.
462 **
463 ** PAT PDC needs to basically do what legacy PDC does:
464 ** o read PIN
465 ** o adjust PIN in case device is "behind" a PPB
466 **     (eg 4-port 100BT and SCSI/LAN "Combo Card")
467 ** o convert slot/pin to I/O SAPIC input line.
468 **
469 ** HP platforms only support:
470 ** o one level of skewing for any number of PPBs
471 ** o only support PCI-PCI Bridges.
472 */
473 static struct irt_entry *
iosapic_xlate_pin(struct iosapic_info * isi,struct pci_dev * pcidev)474 iosapic_xlate_pin(struct iosapic_info *isi, struct pci_dev *pcidev)
475 {
476 	u8 intr_pin, intr_slot;
477 
478 	pci_read_config_byte(pcidev, PCI_INTERRUPT_PIN, &intr_pin);
479 
480 	DBG_IRT("iosapic_xlate_pin(%s) SLOT %d pin %d\n",
481 		pcidev->slot_name, PCI_SLOT(pcidev->devfn), intr_pin);
482 
483 	if (intr_pin == 0) {
484 		/* The device does NOT support/use IRQ lines.  */
485 		return NULL;
486 	}
487 
488 	/* Check if pcidev behind a PPB */
489 	if (pcidev->bus->parent) {
490 		/* Convert pcidev INTR_PIN into something we
491 		** can lookup in the IRT.
492 		*/
493 #ifdef PCI_BRIDGE_FUNCS
494 		/*
495 		** Proposal #1:
496 		**
497 		** call implementation specific translation function
498 		** This is architecturally "cleaner". HP-UX doesn't
499 		** support other secondary bus types (eg. E/ISA) directly.
500 		** May be needed for other processor (eg IA64) architectures
501 		** or by some ambitous soul who wants to watch TV.
502 		*/
503 		if (pci_bridge_funcs->xlate_intr_line) {
504 			intr_pin = pci_bridge_funcs->xlate_intr_line(pcidev);
505 		}
506 #else	/* PCI_BRIDGE_FUNCS */
507 		struct pci_bus *p = pcidev->bus;
508 		/*
509 		** Proposal #2:
510 		** The "pin" is skewed ((pin + dev - 1) % 4).
511 		**
512 		** This isn't very clean since I/O SAPIC must assume:
513 		**   - all platforms only have PCI busses.
514 		**   - only PCI-PCI bridge (eg not PCI-EISA, PCI-PCMCIA)
515 		**   - IRQ routing is only skewed once regardless of
516 		**     the number of PPB's between iosapic and device.
517 		**     (Bit3 expansion chassis follows this rule)
518 		**
519 		** Advantage is it's really easy to implement.
520 		*/
521 		intr_pin = pci_swizzle_interrupt_pin(pcidev, intr_pin);
522 #endif /* PCI_BRIDGE_FUNCS */
523 
524 		/*
525 		 * Locate the host slot of the PPB.
526 		 */
527 		while (p->parent->parent)
528 			p = p->parent;
529 
530 		intr_slot = PCI_SLOT(p->self->devfn);
531 	} else {
532 		intr_slot = PCI_SLOT(pcidev->devfn);
533 	}
534 	DBG_IRT("iosapic_xlate_pin:  bus %d slot %d pin %d\n",
535 			pcidev->bus->busn_res.start, intr_slot, intr_pin);
536 
537 	return irt_find_irqline(isi, intr_slot, intr_pin);
538 }
539 
iosapic_rd_irt_entry(struct vector_info * vi,u32 * dp0,u32 * dp1)540 static void iosapic_rd_irt_entry(struct vector_info *vi , u32 *dp0, u32 *dp1)
541 {
542 	struct iosapic_info *isp = vi->iosapic;
543 	u8 idx = vi->irqline;
544 
545 	*dp0 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY(idx));
546 	*dp1 = iosapic_read(isp->addr, IOSAPIC_IRDT_ENTRY_HI(idx));
547 }
548 
549 
iosapic_wr_irt_entry(struct vector_info * vi,u32 dp0,u32 dp1)550 static void iosapic_wr_irt_entry(struct vector_info *vi, u32 dp0, u32 dp1)
551 {
552 	struct iosapic_info *isp = vi->iosapic;
553 
554 	DBG_IRT("iosapic_wr_irt_entry(): irq %d hpa %lx 0x%x 0x%x\n",
555 		vi->irqline, isp->isi_hpa, dp0, dp1);
556 
557 	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY(vi->irqline), dp0);
558 
559 	/* Read the window register to flush the writes down to HW  */
560 	dp0 = readl(isp->addr+IOSAPIC_REG_WINDOW);
561 
562 	iosapic_write(isp->addr, IOSAPIC_IRDT_ENTRY_HI(vi->irqline), dp1);
563 
564 	/* Read the window register to flush the writes down to HW  */
565 	dp1 = readl(isp->addr+IOSAPIC_REG_WINDOW);
566 }
567 
568 /*
569 ** set_irt prepares the data (dp0, dp1) according to the vector_info
570 ** and target cpu (id_eid).  dp0/dp1 are then used to program I/O SAPIC
571 ** IRdT for the given "vector" (aka IRQ line).
572 */
573 static void
iosapic_set_irt_data(struct vector_info * vi,u32 * dp0,u32 * dp1)574 iosapic_set_irt_data( struct vector_info *vi, u32 *dp0, u32 *dp1)
575 {
576 	u32 mode = 0;
577 	struct irt_entry *p = vi->irte;
578 
579 	if ((p->polarity_trigger & IRT_PO_MASK) == IRT_ACTIVE_LO)
580 		mode |= IOSAPIC_IRDT_PO_LOW;
581 
582 	if (((p->polarity_trigger >> IRT_EL_SHIFT) & IRT_EL_MASK) == IRT_LEVEL_TRIG)
583 		mode |= IOSAPIC_IRDT_LEVEL_TRIG;
584 
585 	/*
586 	** IA64 REVISIT
587 	** PA doesn't support EXTINT or LPRIO bits.
588 	*/
589 
590 	*dp0 = mode | (u32) vi->txn_data;
591 
592 	/*
593 	** Extracting id_eid isn't a real clean way of getting it.
594 	** But the encoding is the same for both PA and IA64 platforms.
595 	*/
596 	if (is_pdc_pat()) {
597 		/*
598 		** PAT PDC just hands it to us "right".
599 		** txn_addr comes from cpu_data[x].txn_addr.
600 		*/
601 		*dp1 = (u32) (vi->txn_addr);
602 	} else {
603 		/*
604 		** eg if base_addr == 0xfffa0000),
605 		**    we want to get 0xa0ff0000.
606 		**
607 		** eid	0x0ff00000 -> 0x00ff0000
608 		** id	0x000ff000 -> 0xff000000
609 		*/
610 		*dp1 = (((u32)vi->txn_addr & 0x0ff00000) >> 4) |
611 			(((u32)vi->txn_addr & 0x000ff000) << 12);
612 	}
613 	DBG_IRT("iosapic_set_irt_data(): 0x%x 0x%x\n", *dp0, *dp1);
614 }
615 
616 
iosapic_mask_irq(struct irq_data * d)617 static void iosapic_mask_irq(struct irq_data *d)
618 {
619 	unsigned long flags;
620 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
621 	u32 d0, d1;
622 
623 	spin_lock_irqsave(&iosapic_lock, flags);
624 	iosapic_rd_irt_entry(vi, &d0, &d1);
625 	d0 |= IOSAPIC_IRDT_ENABLE;
626 	iosapic_wr_irt_entry(vi, d0, d1);
627 	spin_unlock_irqrestore(&iosapic_lock, flags);
628 }
629 
iosapic_unmask_irq(struct irq_data * d)630 static void iosapic_unmask_irq(struct irq_data *d)
631 {
632 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
633 	u32 d0, d1;
634 
635 	/* data is initialized by fixup_irq */
636 	WARN_ON(vi->txn_irq  == 0);
637 
638 	iosapic_set_irt_data(vi, &d0, &d1);
639 	iosapic_wr_irt_entry(vi, d0, d1);
640 
641 #ifdef DEBUG_IOSAPIC_IRT
642 {
643 	u32 *t = (u32 *) ((ulong) vi->eoi_addr & ~0xffUL);
644 	printk("iosapic_enable_irq(): regs %p", vi->eoi_addr);
645 	for ( ; t < vi->eoi_addr; t++)
646 		printk(" %x", readl(t));
647 	printk("\n");
648 }
649 
650 printk("iosapic_enable_irq(): sel ");
651 {
652 	struct iosapic_info *isp = vi->iosapic;
653 
654 	for (d0=0x10; d0<0x1e; d0++) {
655 		d1 = iosapic_read(isp->addr, d0);
656 		printk(" %x", d1);
657 	}
658 }
659 printk("\n");
660 #endif
661 
662 	/*
663 	 * Issuing I/O SAPIC an EOI causes an interrupt IFF IRQ line is
664 	 * asserted.  IRQ generally should not be asserted when a driver
665 	 * enables their IRQ. It can lead to "interesting" race conditions
666 	 * in the driver initialization sequence.
667 	 */
668 	DBG(KERN_DEBUG "enable_irq(%d): eoi(%p, 0x%x)\n", d->irq,
669 			vi->eoi_addr, vi->eoi_data);
670 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
671 }
672 
iosapic_eoi_irq(struct irq_data * d)673 static void iosapic_eoi_irq(struct irq_data *d)
674 {
675 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
676 
677 	iosapic_eoi(vi->eoi_addr, vi->eoi_data);
678 	cpu_eoi_irq(d);
679 }
680 
681 #ifdef CONFIG_SMP
iosapic_set_affinity_irq(struct irq_data * d,const struct cpumask * dest,bool force)682 static int iosapic_set_affinity_irq(struct irq_data *d,
683 				    const struct cpumask *dest, bool force)
684 {
685 	struct vector_info *vi = irq_data_get_irq_chip_data(d);
686 	u32 d0, d1, dummy_d0;
687 	unsigned long flags;
688 	int dest_cpu;
689 
690 	dest_cpu = cpu_check_affinity(d, dest);
691 	if (dest_cpu < 0)
692 		return -1;
693 
694 	cpumask_copy(d->affinity, cpumask_of(dest_cpu));
695 	vi->txn_addr = txn_affinity_addr(d->irq, dest_cpu);
696 
697 	spin_lock_irqsave(&iosapic_lock, flags);
698 	/* d1 contains the destination CPU, so only want to set that
699 	 * entry */
700 	iosapic_rd_irt_entry(vi, &d0, &d1);
701 	iosapic_set_irt_data(vi, &dummy_d0, &d1);
702 	iosapic_wr_irt_entry(vi, d0, d1);
703 	spin_unlock_irqrestore(&iosapic_lock, flags);
704 
705 	return 0;
706 }
707 #endif
708 
709 static struct irq_chip iosapic_interrupt_type = {
710 	.name		=	"IO-SAPIC-level",
711 	.irq_unmask	=	iosapic_unmask_irq,
712 	.irq_mask	=	iosapic_mask_irq,
713 	.irq_ack	=	cpu_ack_irq,
714 	.irq_eoi	=	iosapic_eoi_irq,
715 #ifdef CONFIG_SMP
716 	.irq_set_affinity =	iosapic_set_affinity_irq,
717 #endif
718 };
719 
iosapic_fixup_irq(void * isi_obj,struct pci_dev * pcidev)720 int iosapic_fixup_irq(void *isi_obj, struct pci_dev *pcidev)
721 {
722 	struct iosapic_info *isi = isi_obj;
723 	struct irt_entry *irte = NULL;  /* only used if PAT PDC */
724 	struct vector_info *vi;
725 	int isi_line;	/* line used by device */
726 
727 	if (!isi) {
728 		printk(KERN_WARNING MODULE_NAME ": hpa not registered for %s\n",
729 			pci_name(pcidev));
730 		return -1;
731 	}
732 
733 #ifdef CONFIG_SUPERIO
734 	/*
735 	 * HACK ALERT! (non-compliant PCI device support)
736 	 *
737 	 * All SuckyIO interrupts are routed through the PIC's on function 1.
738 	 * But SuckyIO OHCI USB controller gets an IRT entry anyway because
739 	 * it advertises INT D for INT_PIN.  Use that IRT entry to get the
740 	 * SuckyIO interrupt routing for PICs on function 1 (*BLEECCHH*).
741 	 */
742 	if (is_superio_device(pcidev)) {
743 		/* We must call superio_fixup_irq() to register the pdev */
744 		pcidev->irq = superio_fixup_irq(pcidev);
745 
746 		/* Don't return if need to program the IOSAPIC's IRT... */
747 		if (PCI_FUNC(pcidev->devfn) != SUPERIO_USB_FN)
748 			return pcidev->irq;
749 	}
750 #endif /* CONFIG_SUPERIO */
751 
752 	/* lookup IRT entry for isi/slot/pin set */
753 	irte = iosapic_xlate_pin(isi, pcidev);
754 	if (!irte) {
755 		printk("iosapic: no IRTE for %s (IRQ not connected?)\n",
756 				pci_name(pcidev));
757 		return -1;
758 	}
759 	DBG_IRT("iosapic_fixup_irq(): irte %p %x %x %x %x %x %x %x %x\n",
760 		irte,
761 		irte->entry_type,
762 		irte->entry_length,
763 		irte->polarity_trigger,
764 		irte->src_bus_irq_devno,
765 		irte->src_bus_id,
766 		irte->src_seg_id,
767 		irte->dest_iosapic_intin,
768 		(u32) irte->dest_iosapic_addr);
769 	isi_line = irte->dest_iosapic_intin;
770 
771 	/* get vector info for this input line */
772 	vi = isi->isi_vector + isi_line;
773 	DBG_IRT("iosapic_fixup_irq:  line %d vi 0x%p\n", isi_line, vi);
774 
775 	/* If this IRQ line has already been setup, skip it */
776 	if (vi->irte)
777 		goto out;
778 
779 	vi->irte = irte;
780 
781 	/*
782 	 * Allocate processor IRQ
783 	 *
784 	 * XXX/FIXME The txn_alloc_irq() code and related code should be
785 	 * moved to enable_irq(). That way we only allocate processor IRQ
786 	 * bits for devices that actually have drivers claiming them.
787 	 * Right now we assign an IRQ to every PCI device present,
788 	 * regardless of whether it's used or not.
789 	 */
790 	vi->txn_irq = txn_alloc_irq(8);
791 
792 	if (vi->txn_irq < 0)
793 		panic("I/O sapic: couldn't get TXN IRQ\n");
794 
795 	/* enable_irq() will use txn_* to program IRdT */
796 	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
797 	vi->txn_data = txn_alloc_data(vi->txn_irq);
798 
799 	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
800 	vi->eoi_data = cpu_to_le32(vi->txn_data);
801 
802 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
803 
804  out:
805 	pcidev->irq = vi->txn_irq;
806 
807 	DBG_IRT("iosapic_fixup_irq() %d:%d %x %x line %d irq %d\n",
808 		PCI_SLOT(pcidev->devfn), PCI_FUNC(pcidev->devfn),
809 		pcidev->vendor, pcidev->device, isi_line, pcidev->irq);
810 
811 	return pcidev->irq;
812 }
813 
814 static struct iosapic_info *iosapic_list;
815 
816 #ifdef CONFIG_64BIT
iosapic_serial_irq(struct parisc_device * dev)817 int iosapic_serial_irq(struct parisc_device *dev)
818 {
819 	struct iosapic_info *isi;
820 	struct irt_entry *irte;
821 	struct vector_info *vi;
822 	int cnt;
823 	int intin;
824 
825 	intin = (dev->mod_info >> 24) & 15;
826 
827 	/* lookup IRT entry for isi/slot/pin set */
828 	for (cnt = 0; cnt < irt_num_entry; cnt++) {
829 		irte = &irt_cell[cnt];
830 		if (COMPARE_IRTE_ADDR(irte, dev->mod0) &&
831 		    irte->dest_iosapic_intin == intin)
832 			break;
833 	}
834 	if (cnt >= irt_num_entry)
835 		return 0; /* no irq found, force polling */
836 
837 	DBG_IRT("iosapic_serial_irq(): irte %p %x %x %x %x %x %x %x %x\n",
838 		irte,
839 		irte->entry_type,
840 		irte->entry_length,
841 		irte->polarity_trigger,
842 		irte->src_bus_irq_devno,
843 		irte->src_bus_id,
844 		irte->src_seg_id,
845 		irte->dest_iosapic_intin,
846 		(u32) irte->dest_iosapic_addr);
847 
848 	/* search for iosapic */
849 	for (isi = iosapic_list; isi; isi = isi->isi_next)
850 		if (isi->isi_hpa == dev->mod0)
851 			break;
852 	if (!isi)
853 		return 0; /* no iosapic found, force polling */
854 
855 	/* get vector info for this input line */
856 	vi = isi->isi_vector + intin;
857 	DBG_IRT("iosapic_serial_irq:  line %d vi 0x%p\n", iosapic_intin, vi);
858 
859 	/* If this IRQ line has already been setup, skip it */
860 	if (vi->irte)
861 		goto out;
862 
863 	vi->irte = irte;
864 
865 	/*
866 	 * Allocate processor IRQ
867 	 *
868 	 * XXX/FIXME The txn_alloc_irq() code and related code should be
869 	 * moved to enable_irq(). That way we only allocate processor IRQ
870 	 * bits for devices that actually have drivers claiming them.
871 	 * Right now we assign an IRQ to every PCI device present,
872 	 * regardless of whether it's used or not.
873 	 */
874 	vi->txn_irq = txn_alloc_irq(8);
875 
876 	if (vi->txn_irq < 0)
877 		panic("I/O sapic: couldn't get TXN IRQ\n");
878 
879 	/* enable_irq() will use txn_* to program IRdT */
880 	vi->txn_addr = txn_alloc_addr(vi->txn_irq);
881 	vi->txn_data = txn_alloc_data(vi->txn_irq);
882 
883 	vi->eoi_addr = isi->addr + IOSAPIC_REG_EOI;
884 	vi->eoi_data = cpu_to_le32(vi->txn_data);
885 
886 	cpu_claim_irq(vi->txn_irq, &iosapic_interrupt_type, vi);
887 
888  out:
889 
890 	return vi->txn_irq;
891 }
892 #endif
893 
894 
895 /*
896 ** squirrel away the I/O Sapic Version
897 */
898 static unsigned int
iosapic_rd_version(struct iosapic_info * isi)899 iosapic_rd_version(struct iosapic_info *isi)
900 {
901 	return iosapic_read(isi->addr, IOSAPIC_REG_VERSION);
902 }
903 
904 
905 /*
906 ** iosapic_register() is called by "drivers" with an integrated I/O SAPIC.
907 ** Caller must be certain they have an I/O SAPIC and know its MMIO address.
908 **
909 **	o allocate iosapic_info and add it to the list
910 **	o read iosapic version and squirrel that away
911 **	o read size of IRdT.
912 **	o allocate and initialize isi_vector[]
913 **	o allocate irq region
914 */
iosapic_register(unsigned long hpa)915 void *iosapic_register(unsigned long hpa)
916 {
917 	struct iosapic_info *isi = NULL;
918 	struct irt_entry *irte = irt_cell;
919 	struct vector_info *vip;
920 	int cnt;	/* track how many entries we've looked at */
921 
922 	/*
923 	 * Astro based platforms can only support PCI OLARD if they implement
924 	 * PAT PDC.  Legacy PDC omits LBAs with no PCI devices from the IRT.
925 	 * Search the IRT and ignore iosapic's which aren't in the IRT.
926 	 */
927 	for (cnt=0; cnt < irt_num_entry; cnt++, irte++) {
928 		WARN_ON(IRT_IOSAPIC_TYPE != irte->entry_type);
929 		if (COMPARE_IRTE_ADDR(irte, hpa))
930 			break;
931 	}
932 
933 	if (cnt >= irt_num_entry) {
934 		DBG("iosapic_register() ignoring 0x%lx (NOT FOUND)\n", hpa);
935 		return NULL;
936 	}
937 
938 	isi = kzalloc(sizeof(struct iosapic_info), GFP_KERNEL);
939 	if (!isi) {
940 		BUG();
941 		return NULL;
942 	}
943 
944 	isi->addr = ioremap_nocache(hpa, 4096);
945 	isi->isi_hpa = hpa;
946 	isi->isi_version = iosapic_rd_version(isi);
947 	isi->isi_num_vectors = IOSAPIC_IRDT_MAX_ENTRY(isi->isi_version) + 1;
948 
949 	vip = isi->isi_vector = kcalloc(isi->isi_num_vectors,
950 					sizeof(struct vector_info), GFP_KERNEL);
951 	if (vip == NULL) {
952 		kfree(isi);
953 		return NULL;
954 	}
955 
956 	for (cnt=0; cnt < isi->isi_num_vectors; cnt++, vip++) {
957 		vip->irqline = (unsigned char) cnt;
958 		vip->iosapic = isi;
959 	}
960 	isi->isi_next = iosapic_list;
961 	iosapic_list = isi;
962 	return isi;
963 }
964 
965 
966 #ifdef DEBUG_IOSAPIC
967 
968 static void
iosapic_prt_irt(void * irt,long num_entry)969 iosapic_prt_irt(void *irt, long num_entry)
970 {
971 	unsigned int i, *irp = (unsigned int *) irt;
972 
973 
974 	printk(KERN_DEBUG MODULE_NAME ": Interrupt Routing Table (%lx entries)\n", num_entry);
975 
976 	for (i=0; i<num_entry; i++, irp += 4) {
977 		printk(KERN_DEBUG "%p : %2d %.8x %.8x %.8x %.8x\n",
978 					irp, i, irp[0], irp[1], irp[2], irp[3]);
979 	}
980 }
981 
982 
983 static void
iosapic_prt_vi(struct vector_info * vi)984 iosapic_prt_vi(struct vector_info *vi)
985 {
986 	printk(KERN_DEBUG MODULE_NAME ": vector_info[%d] is at %p\n", vi->irqline, vi);
987 	printk(KERN_DEBUG "\t\tstatus:	 %.4x\n", vi->status);
988 	printk(KERN_DEBUG "\t\ttxn_irq:  %d\n",  vi->txn_irq);
989 	printk(KERN_DEBUG "\t\ttxn_addr: %lx\n", vi->txn_addr);
990 	printk(KERN_DEBUG "\t\ttxn_data: %lx\n", vi->txn_data);
991 	printk(KERN_DEBUG "\t\teoi_addr: %p\n",  vi->eoi_addr);
992 	printk(KERN_DEBUG "\t\teoi_data: %x\n",  vi->eoi_data);
993 }
994 
995 
996 static void
iosapic_prt_isi(struct iosapic_info * isi)997 iosapic_prt_isi(struct iosapic_info *isi)
998 {
999 	printk(KERN_DEBUG MODULE_NAME ": io_sapic_info at %p\n", isi);
1000 	printk(KERN_DEBUG "\t\tisi_hpa:       %lx\n", isi->isi_hpa);
1001 	printk(KERN_DEBUG "\t\tisi_status:    %x\n", isi->isi_status);
1002 	printk(KERN_DEBUG "\t\tisi_version:   %x\n", isi->isi_version);
1003 	printk(KERN_DEBUG "\t\tisi_vector:    %p\n", isi->isi_vector);
1004 }
1005 #endif /* DEBUG_IOSAPIC */
1006