xref: /linux/arch/sparc/kernel/pci_sun4v.c (revision 2277ab4a1df50e05bc732fe9488d4e902bb8399a)
1 /* pci_sun4v.c: SUN4V specific PCI controller support.
2  *
3  * Copyright (C) 2006, 2007, 2008 David S. Miller (davem@davemloft.net)
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/types.h>
8 #include <linux/pci.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/interrupt.h>
12 #include <linux/percpu.h>
13 #include <linux/irq.h>
14 #include <linux/msi.h>
15 #include <linux/log2.h>
16 #include <linux/of_device.h>
17 
18 #include <asm/iommu.h>
19 #include <asm/irq.h>
20 #include <asm/hypervisor.h>
21 #include <asm/prom.h>
22 
23 #include "pci_impl.h"
24 #include "iommu_common.h"
25 
26 #include "pci_sun4v.h"
27 
28 #define DRIVER_NAME	"pci_sun4v"
29 #define PFX		DRIVER_NAME ": "
30 
31 static unsigned long vpci_major = 1;
32 static unsigned long vpci_minor = 1;
33 
34 #define PGLIST_NENTS	(PAGE_SIZE / sizeof(u64))
35 
36 struct iommu_batch {
37 	struct device	*dev;		/* Device mapping is for.	*/
38 	unsigned long	prot;		/* IOMMU page protections	*/
39 	unsigned long	entry;		/* Index into IOTSB.		*/
40 	u64		*pglist;	/* List of physical pages	*/
41 	unsigned long	npages;		/* Number of pages in list.	*/
42 };
43 
44 static DEFINE_PER_CPU(struct iommu_batch, iommu_batch);
45 static int iommu_batch_initialized;
46 
47 /* Interrupts must be disabled.  */
48 static inline void iommu_batch_start(struct device *dev, unsigned long prot, unsigned long entry)
49 {
50 	struct iommu_batch *p = &__get_cpu_var(iommu_batch);
51 
52 	p->dev		= dev;
53 	p->prot		= prot;
54 	p->entry	= entry;
55 	p->npages	= 0;
56 }
57 
58 /* Interrupts must be disabled.  */
59 static long iommu_batch_flush(struct iommu_batch *p)
60 {
61 	struct pci_pbm_info *pbm = p->dev->archdata.host_controller;
62 	unsigned long devhandle = pbm->devhandle;
63 	unsigned long prot = p->prot;
64 	unsigned long entry = p->entry;
65 	u64 *pglist = p->pglist;
66 	unsigned long npages = p->npages;
67 
68 	while (npages != 0) {
69 		long num;
70 
71 		num = pci_sun4v_iommu_map(devhandle, HV_PCI_TSBID(0, entry),
72 					  npages, prot, __pa(pglist));
73 		if (unlikely(num < 0)) {
74 			if (printk_ratelimit())
75 				printk("iommu_batch_flush: IOMMU map of "
76 				       "[%08lx:%08llx:%lx:%lx:%lx] failed with "
77 				       "status %ld\n",
78 				       devhandle, HV_PCI_TSBID(0, entry),
79 				       npages, prot, __pa(pglist), num);
80 			return -1;
81 		}
82 
83 		entry += num;
84 		npages -= num;
85 		pglist += num;
86 	}
87 
88 	p->entry = entry;
89 	p->npages = 0;
90 
91 	return 0;
92 }
93 
94 static inline void iommu_batch_new_entry(unsigned long entry)
95 {
96 	struct iommu_batch *p = &__get_cpu_var(iommu_batch);
97 
98 	if (p->entry + p->npages == entry)
99 		return;
100 	if (p->entry != ~0UL)
101 		iommu_batch_flush(p);
102 	p->entry = entry;
103 }
104 
105 /* Interrupts must be disabled.  */
106 static inline long iommu_batch_add(u64 phys_page)
107 {
108 	struct iommu_batch *p = &__get_cpu_var(iommu_batch);
109 
110 	BUG_ON(p->npages >= PGLIST_NENTS);
111 
112 	p->pglist[p->npages++] = phys_page;
113 	if (p->npages == PGLIST_NENTS)
114 		return iommu_batch_flush(p);
115 
116 	return 0;
117 }
118 
119 /* Interrupts must be disabled.  */
120 static inline long iommu_batch_end(void)
121 {
122 	struct iommu_batch *p = &__get_cpu_var(iommu_batch);
123 
124 	BUG_ON(p->npages >= PGLIST_NENTS);
125 
126 	return iommu_batch_flush(p);
127 }
128 
129 static void *dma_4v_alloc_coherent(struct device *dev, size_t size,
130 				   dma_addr_t *dma_addrp, gfp_t gfp)
131 {
132 	unsigned long flags, order, first_page, npages, n;
133 	struct iommu *iommu;
134 	struct page *page;
135 	void *ret;
136 	long entry;
137 	int nid;
138 
139 	size = IO_PAGE_ALIGN(size);
140 	order = get_order(size);
141 	if (unlikely(order >= MAX_ORDER))
142 		return NULL;
143 
144 	npages = size >> IO_PAGE_SHIFT;
145 
146 	nid = dev->archdata.numa_node;
147 	page = alloc_pages_node(nid, gfp, order);
148 	if (unlikely(!page))
149 		return NULL;
150 
151 	first_page = (unsigned long) page_address(page);
152 	memset((char *)first_page, 0, PAGE_SIZE << order);
153 
154 	iommu = dev->archdata.iommu;
155 
156 	spin_lock_irqsave(&iommu->lock, flags);
157 	entry = iommu_range_alloc(dev, iommu, npages, NULL);
158 	spin_unlock_irqrestore(&iommu->lock, flags);
159 
160 	if (unlikely(entry == DMA_ERROR_CODE))
161 		goto range_alloc_fail;
162 
163 	*dma_addrp = (iommu->page_table_map_base +
164 		      (entry << IO_PAGE_SHIFT));
165 	ret = (void *) first_page;
166 	first_page = __pa(first_page);
167 
168 	local_irq_save(flags);
169 
170 	iommu_batch_start(dev,
171 			  (HV_PCI_MAP_ATTR_READ |
172 			   HV_PCI_MAP_ATTR_WRITE),
173 			  entry);
174 
175 	for (n = 0; n < npages; n++) {
176 		long err = iommu_batch_add(first_page + (n * PAGE_SIZE));
177 		if (unlikely(err < 0L))
178 			goto iommu_map_fail;
179 	}
180 
181 	if (unlikely(iommu_batch_end() < 0L))
182 		goto iommu_map_fail;
183 
184 	local_irq_restore(flags);
185 
186 	return ret;
187 
188 iommu_map_fail:
189 	/* Interrupts are disabled.  */
190 	spin_lock(&iommu->lock);
191 	iommu_range_free(iommu, *dma_addrp, npages);
192 	spin_unlock_irqrestore(&iommu->lock, flags);
193 
194 range_alloc_fail:
195 	free_pages(first_page, order);
196 	return NULL;
197 }
198 
199 static void dma_4v_free_coherent(struct device *dev, size_t size, void *cpu,
200 				 dma_addr_t dvma)
201 {
202 	struct pci_pbm_info *pbm;
203 	struct iommu *iommu;
204 	unsigned long flags, order, npages, entry;
205 	u32 devhandle;
206 
207 	npages = IO_PAGE_ALIGN(size) >> IO_PAGE_SHIFT;
208 	iommu = dev->archdata.iommu;
209 	pbm = dev->archdata.host_controller;
210 	devhandle = pbm->devhandle;
211 	entry = ((dvma - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
212 
213 	spin_lock_irqsave(&iommu->lock, flags);
214 
215 	iommu_range_free(iommu, dvma, npages);
216 
217 	do {
218 		unsigned long num;
219 
220 		num = pci_sun4v_iommu_demap(devhandle, HV_PCI_TSBID(0, entry),
221 					    npages);
222 		entry += num;
223 		npages -= num;
224 	} while (npages != 0);
225 
226 	spin_unlock_irqrestore(&iommu->lock, flags);
227 
228 	order = get_order(size);
229 	if (order < 10)
230 		free_pages((unsigned long)cpu, order);
231 }
232 
233 static dma_addr_t dma_4v_map_page(struct device *dev, struct page *page,
234 				  unsigned long offset, size_t sz,
235 				  enum dma_data_direction direction)
236 {
237 	struct iommu *iommu;
238 	unsigned long flags, npages, oaddr;
239 	unsigned long i, base_paddr;
240 	u32 bus_addr, ret;
241 	unsigned long prot;
242 	long entry;
243 
244 	iommu = dev->archdata.iommu;
245 
246 	if (unlikely(direction == DMA_NONE))
247 		goto bad;
248 
249 	oaddr = (unsigned long)(page_address(page) + offset);
250 	npages = IO_PAGE_ALIGN(oaddr + sz) - (oaddr & IO_PAGE_MASK);
251 	npages >>= IO_PAGE_SHIFT;
252 
253 	spin_lock_irqsave(&iommu->lock, flags);
254 	entry = iommu_range_alloc(dev, iommu, npages, NULL);
255 	spin_unlock_irqrestore(&iommu->lock, flags);
256 
257 	if (unlikely(entry == DMA_ERROR_CODE))
258 		goto bad;
259 
260 	bus_addr = (iommu->page_table_map_base +
261 		    (entry << IO_PAGE_SHIFT));
262 	ret = bus_addr | (oaddr & ~IO_PAGE_MASK);
263 	base_paddr = __pa(oaddr & IO_PAGE_MASK);
264 	prot = HV_PCI_MAP_ATTR_READ;
265 	if (direction != DMA_TO_DEVICE)
266 		prot |= HV_PCI_MAP_ATTR_WRITE;
267 
268 	local_irq_save(flags);
269 
270 	iommu_batch_start(dev, prot, entry);
271 
272 	for (i = 0; i < npages; i++, base_paddr += IO_PAGE_SIZE) {
273 		long err = iommu_batch_add(base_paddr);
274 		if (unlikely(err < 0L))
275 			goto iommu_map_fail;
276 	}
277 	if (unlikely(iommu_batch_end() < 0L))
278 		goto iommu_map_fail;
279 
280 	local_irq_restore(flags);
281 
282 	return ret;
283 
284 bad:
285 	if (printk_ratelimit())
286 		WARN_ON(1);
287 	return DMA_ERROR_CODE;
288 
289 iommu_map_fail:
290 	/* Interrupts are disabled.  */
291 	spin_lock(&iommu->lock);
292 	iommu_range_free(iommu, bus_addr, npages);
293 	spin_unlock_irqrestore(&iommu->lock, flags);
294 
295 	return DMA_ERROR_CODE;
296 }
297 
298 static void dma_4v_unmap_page(struct device *dev, dma_addr_t bus_addr,
299 			      size_t sz, enum dma_data_direction direction)
300 {
301 	struct pci_pbm_info *pbm;
302 	struct iommu *iommu;
303 	unsigned long flags, npages;
304 	long entry;
305 	u32 devhandle;
306 
307 	if (unlikely(direction == DMA_NONE)) {
308 		if (printk_ratelimit())
309 			WARN_ON(1);
310 		return;
311 	}
312 
313 	iommu = dev->archdata.iommu;
314 	pbm = dev->archdata.host_controller;
315 	devhandle = pbm->devhandle;
316 
317 	npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK);
318 	npages >>= IO_PAGE_SHIFT;
319 	bus_addr &= IO_PAGE_MASK;
320 
321 	spin_lock_irqsave(&iommu->lock, flags);
322 
323 	iommu_range_free(iommu, bus_addr, npages);
324 
325 	entry = (bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT;
326 	do {
327 		unsigned long num;
328 
329 		num = pci_sun4v_iommu_demap(devhandle, HV_PCI_TSBID(0, entry),
330 					    npages);
331 		entry += num;
332 		npages -= num;
333 	} while (npages != 0);
334 
335 	spin_unlock_irqrestore(&iommu->lock, flags);
336 }
337 
338 static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist,
339 			 int nelems, enum dma_data_direction direction)
340 {
341 	struct scatterlist *s, *outs, *segstart;
342 	unsigned long flags, handle, prot;
343 	dma_addr_t dma_next = 0, dma_addr;
344 	unsigned int max_seg_size;
345 	unsigned long seg_boundary_size;
346 	int outcount, incount, i;
347 	struct iommu *iommu;
348 	unsigned long base_shift;
349 	long err;
350 
351 	BUG_ON(direction == DMA_NONE);
352 
353 	iommu = dev->archdata.iommu;
354 	if (nelems == 0 || !iommu)
355 		return 0;
356 
357 	prot = HV_PCI_MAP_ATTR_READ;
358 	if (direction != DMA_TO_DEVICE)
359 		prot |= HV_PCI_MAP_ATTR_WRITE;
360 
361 	outs = s = segstart = &sglist[0];
362 	outcount = 1;
363 	incount = nelems;
364 	handle = 0;
365 
366 	/* Init first segment length for backout at failure */
367 	outs->dma_length = 0;
368 
369 	spin_lock_irqsave(&iommu->lock, flags);
370 
371 	iommu_batch_start(dev, prot, ~0UL);
372 
373 	max_seg_size = dma_get_max_seg_size(dev);
374 	seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
375 				  IO_PAGE_SIZE) >> IO_PAGE_SHIFT;
376 	base_shift = iommu->page_table_map_base >> IO_PAGE_SHIFT;
377 	for_each_sg(sglist, s, nelems, i) {
378 		unsigned long paddr, npages, entry, out_entry = 0, slen;
379 
380 		slen = s->length;
381 		/* Sanity check */
382 		if (slen == 0) {
383 			dma_next = 0;
384 			continue;
385 		}
386 		/* Allocate iommu entries for that segment */
387 		paddr = (unsigned long) SG_ENT_PHYS_ADDRESS(s);
388 		npages = iommu_num_pages(paddr, slen, IO_PAGE_SIZE);
389 		entry = iommu_range_alloc(dev, iommu, npages, &handle);
390 
391 		/* Handle failure */
392 		if (unlikely(entry == DMA_ERROR_CODE)) {
393 			if (printk_ratelimit())
394 				printk(KERN_INFO "iommu_alloc failed, iommu %p paddr %lx"
395 				       " npages %lx\n", iommu, paddr, npages);
396 			goto iommu_map_failed;
397 		}
398 
399 		iommu_batch_new_entry(entry);
400 
401 		/* Convert entry to a dma_addr_t */
402 		dma_addr = iommu->page_table_map_base +
403 			(entry << IO_PAGE_SHIFT);
404 		dma_addr |= (s->offset & ~IO_PAGE_MASK);
405 
406 		/* Insert into HW table */
407 		paddr &= IO_PAGE_MASK;
408 		while (npages--) {
409 			err = iommu_batch_add(paddr);
410 			if (unlikely(err < 0L))
411 				goto iommu_map_failed;
412 			paddr += IO_PAGE_SIZE;
413 		}
414 
415 		/* If we are in an open segment, try merging */
416 		if (segstart != s) {
417 			/* We cannot merge if:
418 			 * - allocated dma_addr isn't contiguous to previous allocation
419 			 */
420 			if ((dma_addr != dma_next) ||
421 			    (outs->dma_length + s->length > max_seg_size) ||
422 			    (is_span_boundary(out_entry, base_shift,
423 					      seg_boundary_size, outs, s))) {
424 				/* Can't merge: create a new segment */
425 				segstart = s;
426 				outcount++;
427 				outs = sg_next(outs);
428 			} else {
429 				outs->dma_length += s->length;
430 			}
431 		}
432 
433 		if (segstart == s) {
434 			/* This is a new segment, fill entries */
435 			outs->dma_address = dma_addr;
436 			outs->dma_length = slen;
437 			out_entry = entry;
438 		}
439 
440 		/* Calculate next page pointer for contiguous check */
441 		dma_next = dma_addr + slen;
442 	}
443 
444 	err = iommu_batch_end();
445 
446 	if (unlikely(err < 0L))
447 		goto iommu_map_failed;
448 
449 	spin_unlock_irqrestore(&iommu->lock, flags);
450 
451 	if (outcount < incount) {
452 		outs = sg_next(outs);
453 		outs->dma_address = DMA_ERROR_CODE;
454 		outs->dma_length = 0;
455 	}
456 
457 	return outcount;
458 
459 iommu_map_failed:
460 	for_each_sg(sglist, s, nelems, i) {
461 		if (s->dma_length != 0) {
462 			unsigned long vaddr, npages;
463 
464 			vaddr = s->dma_address & IO_PAGE_MASK;
465 			npages = iommu_num_pages(s->dma_address, s->dma_length,
466 						 IO_PAGE_SIZE);
467 			iommu_range_free(iommu, vaddr, npages);
468 			/* XXX demap? XXX */
469 			s->dma_address = DMA_ERROR_CODE;
470 			s->dma_length = 0;
471 		}
472 		if (s == outs)
473 			break;
474 	}
475 	spin_unlock_irqrestore(&iommu->lock, flags);
476 
477 	return 0;
478 }
479 
480 static void dma_4v_unmap_sg(struct device *dev, struct scatterlist *sglist,
481 			    int nelems, enum dma_data_direction direction)
482 {
483 	struct pci_pbm_info *pbm;
484 	struct scatterlist *sg;
485 	struct iommu *iommu;
486 	unsigned long flags;
487 	u32 devhandle;
488 
489 	BUG_ON(direction == DMA_NONE);
490 
491 	iommu = dev->archdata.iommu;
492 	pbm = dev->archdata.host_controller;
493 	devhandle = pbm->devhandle;
494 
495 	spin_lock_irqsave(&iommu->lock, flags);
496 
497 	sg = sglist;
498 	while (nelems--) {
499 		dma_addr_t dma_handle = sg->dma_address;
500 		unsigned int len = sg->dma_length;
501 		unsigned long npages, entry;
502 
503 		if (!len)
504 			break;
505 		npages = iommu_num_pages(dma_handle, len, IO_PAGE_SIZE);
506 		iommu_range_free(iommu, dma_handle, npages);
507 
508 		entry = ((dma_handle - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
509 		while (npages) {
510 			unsigned long num;
511 
512 			num = pci_sun4v_iommu_demap(devhandle, HV_PCI_TSBID(0, entry),
513 						    npages);
514 			entry += num;
515 			npages -= num;
516 		}
517 
518 		sg = sg_next(sg);
519 	}
520 
521 	spin_unlock_irqrestore(&iommu->lock, flags);
522 }
523 
524 static void dma_4v_sync_single_for_cpu(struct device *dev,
525 				       dma_addr_t bus_addr, size_t sz,
526 				       enum dma_data_direction direction)
527 {
528 	/* Nothing to do... */
529 }
530 
531 static void dma_4v_sync_sg_for_cpu(struct device *dev,
532 				   struct scatterlist *sglist, int nelems,
533 				   enum dma_data_direction direction)
534 {
535 	/* Nothing to do... */
536 }
537 
538 static const struct dma_ops sun4v_dma_ops = {
539 	.alloc_coherent			= dma_4v_alloc_coherent,
540 	.free_coherent			= dma_4v_free_coherent,
541 	.map_page			= dma_4v_map_page,
542 	.unmap_page			= dma_4v_unmap_page,
543 	.map_sg				= dma_4v_map_sg,
544 	.unmap_sg			= dma_4v_unmap_sg,
545 	.sync_single_for_cpu		= dma_4v_sync_single_for_cpu,
546 	.sync_sg_for_cpu		= dma_4v_sync_sg_for_cpu,
547 };
548 
549 static void __devinit pci_sun4v_scan_bus(struct pci_pbm_info *pbm,
550 					 struct device *parent)
551 {
552 	struct property *prop;
553 	struct device_node *dp;
554 
555 	dp = pbm->op->node;
556 	prop = of_find_property(dp, "66mhz-capable", NULL);
557 	pbm->is_66mhz_capable = (prop != NULL);
558 	pbm->pci_bus = pci_scan_one_pbm(pbm, parent);
559 
560 	/* XXX register error interrupt handlers XXX */
561 }
562 
563 static unsigned long __devinit probe_existing_entries(struct pci_pbm_info *pbm,
564 						      struct iommu *iommu)
565 {
566 	struct iommu_arena *arena = &iommu->arena;
567 	unsigned long i, cnt = 0;
568 	u32 devhandle;
569 
570 	devhandle = pbm->devhandle;
571 	for (i = 0; i < arena->limit; i++) {
572 		unsigned long ret, io_attrs, ra;
573 
574 		ret = pci_sun4v_iommu_getmap(devhandle,
575 					     HV_PCI_TSBID(0, i),
576 					     &io_attrs, &ra);
577 		if (ret == HV_EOK) {
578 			if (page_in_phys_avail(ra)) {
579 				pci_sun4v_iommu_demap(devhandle,
580 						      HV_PCI_TSBID(0, i), 1);
581 			} else {
582 				cnt++;
583 				__set_bit(i, arena->map);
584 			}
585 		}
586 	}
587 
588 	return cnt;
589 }
590 
591 static int __devinit pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
592 {
593 	static const u32 vdma_default[] = { 0x80000000, 0x80000000 };
594 	struct iommu *iommu = pbm->iommu;
595 	unsigned long num_tsb_entries, sz, tsbsize;
596 	u32 dma_mask, dma_offset;
597 	const u32 *vdma;
598 
599 	vdma = of_get_property(pbm->op->node, "virtual-dma", NULL);
600 	if (!vdma)
601 		vdma = vdma_default;
602 
603 	if ((vdma[0] | vdma[1]) & ~IO_PAGE_MASK) {
604 		printk(KERN_ERR PFX "Strange virtual-dma[%08x:%08x].\n",
605 		       vdma[0], vdma[1]);
606 		return -EINVAL;
607 	};
608 
609 	dma_mask = (roundup_pow_of_two(vdma[1]) - 1UL);
610 	num_tsb_entries = vdma[1] / IO_PAGE_SIZE;
611 	tsbsize = num_tsb_entries * sizeof(iopte_t);
612 
613 	dma_offset = vdma[0];
614 
615 	/* Setup initial software IOMMU state. */
616 	spin_lock_init(&iommu->lock);
617 	iommu->ctx_lowest_free = 1;
618 	iommu->page_table_map_base = dma_offset;
619 	iommu->dma_addr_mask = dma_mask;
620 
621 	/* Allocate and initialize the free area map.  */
622 	sz = (num_tsb_entries + 7) / 8;
623 	sz = (sz + 7UL) & ~7UL;
624 	iommu->arena.map = kzalloc(sz, GFP_KERNEL);
625 	if (!iommu->arena.map) {
626 		printk(KERN_ERR PFX "Error, kmalloc(arena.map) failed.\n");
627 		return -ENOMEM;
628 	}
629 	iommu->arena.limit = num_tsb_entries;
630 
631 	sz = probe_existing_entries(pbm, iommu);
632 	if (sz)
633 		printk("%s: Imported %lu TSB entries from OBP\n",
634 		       pbm->name, sz);
635 
636 	return 0;
637 }
638 
639 #ifdef CONFIG_PCI_MSI
640 struct pci_sun4v_msiq_entry {
641 	u64		version_type;
642 #define MSIQ_VERSION_MASK		0xffffffff00000000UL
643 #define MSIQ_VERSION_SHIFT		32
644 #define MSIQ_TYPE_MASK			0x00000000000000ffUL
645 #define MSIQ_TYPE_SHIFT			0
646 #define MSIQ_TYPE_NONE			0x00
647 #define MSIQ_TYPE_MSG			0x01
648 #define MSIQ_TYPE_MSI32			0x02
649 #define MSIQ_TYPE_MSI64			0x03
650 #define MSIQ_TYPE_INTX			0x08
651 #define MSIQ_TYPE_NONE2			0xff
652 
653 	u64		intx_sysino;
654 	u64		reserved1;
655 	u64		stick;
656 	u64		req_id;  /* bus/device/func */
657 #define MSIQ_REQID_BUS_MASK		0xff00UL
658 #define MSIQ_REQID_BUS_SHIFT		8
659 #define MSIQ_REQID_DEVICE_MASK		0x00f8UL
660 #define MSIQ_REQID_DEVICE_SHIFT		3
661 #define MSIQ_REQID_FUNC_MASK		0x0007UL
662 #define MSIQ_REQID_FUNC_SHIFT		0
663 
664 	u64		msi_address;
665 
666 	/* The format of this value is message type dependent.
667 	 * For MSI bits 15:0 are the data from the MSI packet.
668 	 * For MSI-X bits 31:0 are the data from the MSI packet.
669 	 * For MSG, the message code and message routing code where:
670 	 * 	bits 39:32 is the bus/device/fn of the msg target-id
671 	 *	bits 18:16 is the message routing code
672 	 *	bits 7:0 is the message code
673 	 * For INTx the low order 2-bits are:
674 	 *	00 - INTA
675 	 *	01 - INTB
676 	 *	10 - INTC
677 	 *	11 - INTD
678 	 */
679 	u64		msi_data;
680 
681 	u64		reserved2;
682 };
683 
684 static int pci_sun4v_get_head(struct pci_pbm_info *pbm, unsigned long msiqid,
685 			      unsigned long *head)
686 {
687 	unsigned long err, limit;
688 
689 	err = pci_sun4v_msiq_gethead(pbm->devhandle, msiqid, head);
690 	if (unlikely(err))
691 		return -ENXIO;
692 
693 	limit = pbm->msiq_ent_count * sizeof(struct pci_sun4v_msiq_entry);
694 	if (unlikely(*head >= limit))
695 		return -EFBIG;
696 
697 	return 0;
698 }
699 
700 static int pci_sun4v_dequeue_msi(struct pci_pbm_info *pbm,
701 				 unsigned long msiqid, unsigned long *head,
702 				 unsigned long *msi)
703 {
704 	struct pci_sun4v_msiq_entry *ep;
705 	unsigned long err, type;
706 
707 	/* Note: void pointer arithmetic, 'head' is a byte offset  */
708 	ep = (pbm->msi_queues + ((msiqid - pbm->msiq_first) *
709 				 (pbm->msiq_ent_count *
710 				  sizeof(struct pci_sun4v_msiq_entry))) +
711 	      *head);
712 
713 	if ((ep->version_type & MSIQ_TYPE_MASK) == 0)
714 		return 0;
715 
716 	type = (ep->version_type & MSIQ_TYPE_MASK) >> MSIQ_TYPE_SHIFT;
717 	if (unlikely(type != MSIQ_TYPE_MSI32 &&
718 		     type != MSIQ_TYPE_MSI64))
719 		return -EINVAL;
720 
721 	*msi = ep->msi_data;
722 
723 	err = pci_sun4v_msi_setstate(pbm->devhandle,
724 				     ep->msi_data /* msi_num */,
725 				     HV_MSISTATE_IDLE);
726 	if (unlikely(err))
727 		return -ENXIO;
728 
729 	/* Clear the entry.  */
730 	ep->version_type &= ~MSIQ_TYPE_MASK;
731 
732 	(*head) += sizeof(struct pci_sun4v_msiq_entry);
733 	if (*head >=
734 	    (pbm->msiq_ent_count * sizeof(struct pci_sun4v_msiq_entry)))
735 		*head = 0;
736 
737 	return 1;
738 }
739 
740 static int pci_sun4v_set_head(struct pci_pbm_info *pbm, unsigned long msiqid,
741 			      unsigned long head)
742 {
743 	unsigned long err;
744 
745 	err = pci_sun4v_msiq_sethead(pbm->devhandle, msiqid, head);
746 	if (unlikely(err))
747 		return -EINVAL;
748 
749 	return 0;
750 }
751 
752 static int pci_sun4v_msi_setup(struct pci_pbm_info *pbm, unsigned long msiqid,
753 			       unsigned long msi, int is_msi64)
754 {
755 	if (pci_sun4v_msi_setmsiq(pbm->devhandle, msi, msiqid,
756 				  (is_msi64 ?
757 				   HV_MSITYPE_MSI64 : HV_MSITYPE_MSI32)))
758 		return -ENXIO;
759 	if (pci_sun4v_msi_setstate(pbm->devhandle, msi, HV_MSISTATE_IDLE))
760 		return -ENXIO;
761 	if (pci_sun4v_msi_setvalid(pbm->devhandle, msi, HV_MSIVALID_VALID))
762 		return -ENXIO;
763 	return 0;
764 }
765 
766 static int pci_sun4v_msi_teardown(struct pci_pbm_info *pbm, unsigned long msi)
767 {
768 	unsigned long err, msiqid;
769 
770 	err = pci_sun4v_msi_getmsiq(pbm->devhandle, msi, &msiqid);
771 	if (err)
772 		return -ENXIO;
773 
774 	pci_sun4v_msi_setvalid(pbm->devhandle, msi, HV_MSIVALID_INVALID);
775 
776 	return 0;
777 }
778 
779 static int pci_sun4v_msiq_alloc(struct pci_pbm_info *pbm)
780 {
781 	unsigned long q_size, alloc_size, pages, order;
782 	int i;
783 
784 	q_size = pbm->msiq_ent_count * sizeof(struct pci_sun4v_msiq_entry);
785 	alloc_size = (pbm->msiq_num * q_size);
786 	order = get_order(alloc_size);
787 	pages = __get_free_pages(GFP_KERNEL | __GFP_COMP, order);
788 	if (pages == 0UL) {
789 		printk(KERN_ERR "MSI: Cannot allocate MSI queues (o=%lu).\n",
790 		       order);
791 		return -ENOMEM;
792 	}
793 	memset((char *)pages, 0, PAGE_SIZE << order);
794 	pbm->msi_queues = (void *) pages;
795 
796 	for (i = 0; i < pbm->msiq_num; i++) {
797 		unsigned long err, base = __pa(pages + (i * q_size));
798 		unsigned long ret1, ret2;
799 
800 		err = pci_sun4v_msiq_conf(pbm->devhandle,
801 					  pbm->msiq_first + i,
802 					  base, pbm->msiq_ent_count);
803 		if (err) {
804 			printk(KERN_ERR "MSI: msiq register fails (err=%lu)\n",
805 			       err);
806 			goto h_error;
807 		}
808 
809 		err = pci_sun4v_msiq_info(pbm->devhandle,
810 					  pbm->msiq_first + i,
811 					  &ret1, &ret2);
812 		if (err) {
813 			printk(KERN_ERR "MSI: Cannot read msiq (err=%lu)\n",
814 			       err);
815 			goto h_error;
816 		}
817 		if (ret1 != base || ret2 != pbm->msiq_ent_count) {
818 			printk(KERN_ERR "MSI: Bogus qconf "
819 			       "expected[%lx:%x] got[%lx:%lx]\n",
820 			       base, pbm->msiq_ent_count,
821 			       ret1, ret2);
822 			goto h_error;
823 		}
824 	}
825 
826 	return 0;
827 
828 h_error:
829 	free_pages(pages, order);
830 	return -EINVAL;
831 }
832 
833 static void pci_sun4v_msiq_free(struct pci_pbm_info *pbm)
834 {
835 	unsigned long q_size, alloc_size, pages, order;
836 	int i;
837 
838 	for (i = 0; i < pbm->msiq_num; i++) {
839 		unsigned long msiqid = pbm->msiq_first + i;
840 
841 		(void) pci_sun4v_msiq_conf(pbm->devhandle, msiqid, 0UL, 0);
842 	}
843 
844 	q_size = pbm->msiq_ent_count * sizeof(struct pci_sun4v_msiq_entry);
845 	alloc_size = (pbm->msiq_num * q_size);
846 	order = get_order(alloc_size);
847 
848 	pages = (unsigned long) pbm->msi_queues;
849 
850 	free_pages(pages, order);
851 
852 	pbm->msi_queues = NULL;
853 }
854 
855 static int pci_sun4v_msiq_build_irq(struct pci_pbm_info *pbm,
856 				    unsigned long msiqid,
857 				    unsigned long devino)
858 {
859 	unsigned int virt_irq = sun4v_build_irq(pbm->devhandle, devino);
860 
861 	if (!virt_irq)
862 		return -ENOMEM;
863 
864 	if (pci_sun4v_msiq_setstate(pbm->devhandle, msiqid, HV_MSIQSTATE_IDLE))
865 		return -EINVAL;
866 	if (pci_sun4v_msiq_setvalid(pbm->devhandle, msiqid, HV_MSIQ_VALID))
867 		return -EINVAL;
868 
869 	return virt_irq;
870 }
871 
872 static const struct sparc64_msiq_ops pci_sun4v_msiq_ops = {
873 	.get_head	=	pci_sun4v_get_head,
874 	.dequeue_msi	=	pci_sun4v_dequeue_msi,
875 	.set_head	=	pci_sun4v_set_head,
876 	.msi_setup	=	pci_sun4v_msi_setup,
877 	.msi_teardown	=	pci_sun4v_msi_teardown,
878 	.msiq_alloc	=	pci_sun4v_msiq_alloc,
879 	.msiq_free	=	pci_sun4v_msiq_free,
880 	.msiq_build_irq	=	pci_sun4v_msiq_build_irq,
881 };
882 
883 static void pci_sun4v_msi_init(struct pci_pbm_info *pbm)
884 {
885 	sparc64_pbm_msi_init(pbm, &pci_sun4v_msiq_ops);
886 }
887 #else /* CONFIG_PCI_MSI */
888 static void pci_sun4v_msi_init(struct pci_pbm_info *pbm)
889 {
890 }
891 #endif /* !(CONFIG_PCI_MSI) */
892 
893 static int __devinit pci_sun4v_pbm_init(struct pci_pbm_info *pbm,
894 					struct of_device *op, u32 devhandle)
895 {
896 	struct device_node *dp = op->node;
897 	int err;
898 
899 	pbm->numa_node = of_node_to_nid(dp);
900 
901 	pbm->pci_ops = &sun4v_pci_ops;
902 	pbm->config_space_reg_bits = 12;
903 
904 	pbm->index = pci_num_pbms++;
905 
906 	pbm->op = op;
907 
908 	pbm->devhandle = devhandle;
909 
910 	pbm->name = dp->full_name;
911 
912 	printk("%s: SUN4V PCI Bus Module\n", pbm->name);
913 	printk("%s: On NUMA node %d\n", pbm->name, pbm->numa_node);
914 
915 	pci_determine_mem_io_space(pbm);
916 
917 	pci_get_pbm_props(pbm);
918 
919 	err = pci_sun4v_iommu_init(pbm);
920 	if (err)
921 		return err;
922 
923 	pci_sun4v_msi_init(pbm);
924 
925 	pci_sun4v_scan_bus(pbm, &op->dev);
926 
927 	pbm->next = pci_pbm_root;
928 	pci_pbm_root = pbm;
929 
930 	return 0;
931 }
932 
933 static int __devinit pci_sun4v_probe(struct of_device *op,
934 				     const struct of_device_id *match)
935 {
936 	const struct linux_prom64_registers *regs;
937 	static int hvapi_negotiated = 0;
938 	struct pci_pbm_info *pbm;
939 	struct device_node *dp;
940 	struct iommu *iommu;
941 	u32 devhandle;
942 	int i, err;
943 
944 	dp = op->node;
945 
946 	if (!hvapi_negotiated++) {
947 		err = sun4v_hvapi_register(HV_GRP_PCI,
948 					   vpci_major,
949 					   &vpci_minor);
950 
951 		if (err) {
952 			printk(KERN_ERR PFX "Could not register hvapi, "
953 			       "err=%d\n", err);
954 			return err;
955 		}
956 		printk(KERN_INFO PFX "Registered hvapi major[%lu] minor[%lu]\n",
957 		       vpci_major, vpci_minor);
958 
959 		dma_ops = &sun4v_dma_ops;
960 	}
961 
962 	regs = of_get_property(dp, "reg", NULL);
963 	err = -ENODEV;
964 	if (!regs) {
965 		printk(KERN_ERR PFX "Could not find config registers\n");
966 		goto out_err;
967 	}
968 	devhandle = (regs->phys_addr >> 32UL) & 0x0fffffff;
969 
970 	err = -ENOMEM;
971 	if (!iommu_batch_initialized) {
972 		for_each_possible_cpu(i) {
973 			unsigned long page = get_zeroed_page(GFP_KERNEL);
974 
975 			if (!page)
976 				goto out_err;
977 
978 			per_cpu(iommu_batch, i).pglist = (u64 *) page;
979 		}
980 		iommu_batch_initialized = 1;
981 	}
982 
983 	pbm = kzalloc(sizeof(*pbm), GFP_KERNEL);
984 	if (!pbm) {
985 		printk(KERN_ERR PFX "Could not allocate pci_pbm_info\n");
986 		goto out_err;
987 	}
988 
989 	iommu = kzalloc(sizeof(struct iommu), GFP_KERNEL);
990 	if (!iommu) {
991 		printk(KERN_ERR PFX "Could not allocate pbm iommu\n");
992 		goto out_free_controller;
993 	}
994 
995 	pbm->iommu = iommu;
996 
997 	err = pci_sun4v_pbm_init(pbm, op, devhandle);
998 	if (err)
999 		goto out_free_iommu;
1000 
1001 	dev_set_drvdata(&op->dev, pbm);
1002 
1003 	return 0;
1004 
1005 out_free_iommu:
1006 	kfree(pbm->iommu);
1007 
1008 out_free_controller:
1009 	kfree(pbm);
1010 
1011 out_err:
1012 	return err;
1013 }
1014 
1015 static struct of_device_id __initdata pci_sun4v_match[] = {
1016 	{
1017 		.name = "pci",
1018 		.compatible = "SUNW,sun4v-pci",
1019 	},
1020 	{},
1021 };
1022 
1023 static struct of_platform_driver pci_sun4v_driver = {
1024 	.name		= DRIVER_NAME,
1025 	.match_table	= pci_sun4v_match,
1026 	.probe		= pci_sun4v_probe,
1027 };
1028 
1029 static int __init pci_sun4v_init(void)
1030 {
1031 	return of_register_driver(&pci_sun4v_driver, &of_bus_type);
1032 }
1033 
1034 subsys_initcall(pci_sun4v_init);
1035