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
iosapic_read(void __iomem * iosapic,unsigned int reg)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
iosapic_write(void __iomem * iosapic,unsigned int reg,u32 val)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
iosapic_eoi(__le32 __iomem * addr,__le32 data)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
iosapic_alloc_irt(int num_entries)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
iosapic_load_irt(unsigned long cell_num,struct irt_entry ** irt)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
iosapic_init(void)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 *
irt_find_irqline(struct iosapic_info * isi,u8 slot,u8 intr_pin)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 *
iosapic_xlate_pin(struct iosapic_info * isi,struct pci_dev * pcidev)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
iosapic_rd_irt_entry(struct vector_info * vi,u32 * dp0,u32 * dp1)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
iosapic_wr_irt_entry(struct vector_info * vi,u32 dp0,u32 dp1)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
iosapic_set_irt_data(struct vector_info * vi,u32 * dp0,u32 * dp1)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
iosapic_mask_irq(struct irq_data * d)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
iosapic_unmask_irq(struct irq_data * d)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
iosapic_eoi_irq(struct irq_data * d)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
iosapic_set_affinity_irq(struct irq_data * d,const struct cpumask * dest,bool force)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
iosapic_fixup_irq(void * isi_obj,struct pci_dev * pcidev)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
iosapic_serial_irq(struct parisc_device * dev)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 EXPORT_SYMBOL(iosapic_serial_irq);
879 #endif
880
881
882 /*
883 ** squirrel away the I/O Sapic Version
884 */
885 static unsigned int
iosapic_rd_version(struct iosapic_info * isi)886 iosapic_rd_version(struct iosapic_info *isi)
887 {
888 return iosapic_read(isi->addr, IOSAPIC_REG_VERSION);
889 }
890
891
892 /*
893 ** iosapic_register() is called by "drivers" with an integrated I/O SAPIC.
894 ** Caller must be certain they have an I/O SAPIC and know its MMIO address.
895 **
896 ** o allocate iosapic_info and add it to the list
897 ** o read iosapic version and squirrel that away
898 ** o read size of IRdT.
899 ** o allocate and initialize isi_vector[]
900 ** o allocate irq region
901 */
iosapic_register(unsigned long hpa)902 void *iosapic_register(unsigned long hpa)
903 {
904 struct iosapic_info *isi = NULL;
905 struct irt_entry *irte = irt_cell;
906 struct vector_info *vip;
907 int cnt; /* track how many entries we've looked at */
908
909 /*
910 * Astro based platforms can only support PCI OLARD if they implement
911 * PAT PDC. Legacy PDC omits LBAs with no PCI devices from the IRT.
912 * Search the IRT and ignore iosapic's which aren't in the IRT.
913 */
914 for (cnt=0; cnt < irt_num_entry; cnt++, irte++) {
915 WARN_ON(IRT_IOSAPIC_TYPE != irte->entry_type);
916 if (COMPARE_IRTE_ADDR(irte, hpa))
917 break;
918 }
919
920 if (cnt >= irt_num_entry) {
921 DBG("iosapic_register() ignoring 0x%lx (NOT FOUND)\n", hpa);
922 return NULL;
923 }
924
925 isi = kzalloc(sizeof(struct iosapic_info), GFP_KERNEL);
926 if (!isi) {
927 BUG();
928 return NULL;
929 }
930
931 isi->addr = ioremap(hpa, 4096);
932 isi->isi_hpa = hpa;
933 isi->isi_version = iosapic_rd_version(isi);
934 isi->isi_num_vectors = IOSAPIC_IRDT_MAX_ENTRY(isi->isi_version) + 1;
935
936 vip = isi->isi_vector = kcalloc(isi->isi_num_vectors,
937 sizeof(struct vector_info), GFP_KERNEL);
938 if (vip == NULL) {
939 kfree(isi);
940 return NULL;
941 }
942
943 for (cnt=0; cnt < isi->isi_num_vectors; cnt++, vip++) {
944 vip->irqline = (unsigned char) cnt;
945 vip->iosapic = isi;
946 }
947 isi->isi_next = iosapic_list;
948 iosapic_list = isi;
949 return isi;
950 }
951
952
953 #ifdef DEBUG_IOSAPIC
954
955 static void
iosapic_prt_irt(void * irt,long num_entry)956 iosapic_prt_irt(void *irt, long num_entry)
957 {
958 unsigned int i, *irp = (unsigned int *) irt;
959
960
961 printk(KERN_DEBUG MODULE_NAME ": Interrupt Routing Table (%lx entries)\n", num_entry);
962
963 for (i=0; i<num_entry; i++, irp += 4) {
964 printk(KERN_DEBUG "%p : %2d %.8x %.8x %.8x %.8x\n",
965 irp, i, irp[0], irp[1], irp[2], irp[3]);
966 }
967 }
968
969
970 static void
iosapic_prt_vi(struct vector_info * vi)971 iosapic_prt_vi(struct vector_info *vi)
972 {
973 printk(KERN_DEBUG MODULE_NAME ": vector_info[%d] is at %p\n", vi->irqline, vi);
974 printk(KERN_DEBUG "\t\tstatus: %.4x\n", vi->status);
975 printk(KERN_DEBUG "\t\ttxn_irq: %d\n", vi->txn_irq);
976 printk(KERN_DEBUG "\t\ttxn_addr: %lx\n", vi->txn_addr);
977 printk(KERN_DEBUG "\t\ttxn_data: %lx\n", vi->txn_data);
978 printk(KERN_DEBUG "\t\teoi_addr: %p\n", vi->eoi_addr);
979 printk(KERN_DEBUG "\t\teoi_data: %x\n", vi->eoi_data);
980 }
981
982
983 static void
iosapic_prt_isi(struct iosapic_info * isi)984 iosapic_prt_isi(struct iosapic_info *isi)
985 {
986 printk(KERN_DEBUG MODULE_NAME ": io_sapic_info at %p\n", isi);
987 printk(KERN_DEBUG "\t\tisi_hpa: %lx\n", isi->isi_hpa);
988 printk(KERN_DEBUG "\t\tisi_status: %x\n", isi->isi_status);
989 printk(KERN_DEBUG "\t\tisi_version: %x\n", isi->isi_version);
990 printk(KERN_DEBUG "\t\tisi_vector: %p\n", isi->isi_vector);
991 }
992 #endif /* DEBUG_IOSAPIC */
993