[PATCH] x86_64: Calgary IOMMU - fix off by one error
[pandora-kernel.git] / arch / x86_64 / kernel / pci-calgary.c
1 /*
2  * Derived from arch/powerpc/kernel/iommu.c
3  *
4  * Copyright (C) IBM Corporation, 2006
5  *
6  * Author: Jon Mason <jdmason@us.ibm.com>
7  * Author: Muli Ben-Yehuda <muli@il.ibm.com>
8
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
22  */
23
24 #include <linux/config.h>
25 #include <linux/kernel.h>
26 #include <linux/init.h>
27 #include <linux/types.h>
28 #include <linux/slab.h>
29 #include <linux/mm.h>
30 #include <linux/spinlock.h>
31 #include <linux/string.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/init.h>
34 #include <linux/bitops.h>
35 #include <linux/pci_ids.h>
36 #include <linux/pci.h>
37 #include <linux/delay.h>
38 #include <asm/proto.h>
39 #include <asm/calgary.h>
40 #include <asm/tce.h>
41 #include <asm/pci-direct.h>
42 #include <asm/system.h>
43 #include <asm/dma.h>
44
45 #define PCI_DEVICE_ID_IBM_CALGARY 0x02a1
46 #define PCI_VENDOR_DEVICE_ID_CALGARY \
47         (PCI_VENDOR_ID_IBM | PCI_DEVICE_ID_IBM_CALGARY << 16)
48
49 /* we need these for register space address calculation */
50 #define START_ADDRESS           0xfe000000
51 #define CHASSIS_BASE            0
52 #define ONE_BASED_CHASSIS_NUM   1
53
54 /* register offsets inside the host bridge space */
55 #define PHB_CSR_OFFSET          0x0110
56 #define PHB_PLSSR_OFFSET        0x0120
57 #define PHB_CONFIG_RW_OFFSET    0x0160
58 #define PHB_IOBASE_BAR_LOW      0x0170
59 #define PHB_IOBASE_BAR_HIGH     0x0180
60 #define PHB_MEM_1_LOW           0x0190
61 #define PHB_MEM_1_HIGH          0x01A0
62 #define PHB_IO_ADDR_SIZE        0x01B0
63 #define PHB_MEM_1_SIZE          0x01C0
64 #define PHB_MEM_ST_OFFSET       0x01D0
65 #define PHB_AER_OFFSET          0x0200
66 #define PHB_CONFIG_0_HIGH       0x0220
67 #define PHB_CONFIG_0_LOW        0x0230
68 #define PHB_CONFIG_0_END        0x0240
69 #define PHB_MEM_2_LOW           0x02B0
70 #define PHB_MEM_2_HIGH          0x02C0
71 #define PHB_MEM_2_SIZE_HIGH     0x02D0
72 #define PHB_MEM_2_SIZE_LOW      0x02E0
73 #define PHB_DOSHOLE_OFFSET      0x08E0
74
75 /* PHB_CONFIG_RW */
76 #define PHB_TCE_ENABLE          0x20000000
77 #define PHB_SLOT_DISABLE        0x1C000000
78 #define PHB_DAC_DISABLE         0x01000000
79 #define PHB_MEM2_ENABLE         0x00400000
80 #define PHB_MCSR_ENABLE         0x00100000
81 /* TAR (Table Address Register) */
82 #define TAR_SW_BITS             0x0000ffffffff800fUL
83 #define TAR_VALID               0x0000000000000008UL
84 /* CSR (Channel/DMA Status Register) */
85 #define CSR_AGENT_MASK          0xffe0ffff
86
87 #define MAX_NUM_OF_PHBS         8 /* how many PHBs in total? */
88 #define MAX_PHB_BUS_NUM         (MAX_NUM_OF_PHBS * 2) /* max dev->bus->number */
89 #define PHBS_PER_CALGARY        4
90
91 /* register offsets in Calgary's internal register space */
92 static const unsigned long tar_offsets[] = {
93         0x0580 /* TAR0 */,
94         0x0588 /* TAR1 */,
95         0x0590 /* TAR2 */,
96         0x0598 /* TAR3 */
97 };
98
99 static const unsigned long split_queue_offsets[] = {
100         0x4870 /* SPLIT QUEUE 0 */,
101         0x5870 /* SPLIT QUEUE 1 */,
102         0x6870 /* SPLIT QUEUE 2 */,
103         0x7870 /* SPLIT QUEUE 3 */
104 };
105
106 static const unsigned long phb_offsets[] = {
107         0x8000 /* PHB0 */,
108         0x9000 /* PHB1 */,
109         0xA000 /* PHB2 */,
110         0xB000 /* PHB3 */
111 };
112
113 void* tce_table_kva[MAX_NUM_OF_PHBS * MAX_NUMNODES];
114 unsigned int specified_table_size = TCE_TABLE_SIZE_UNSPECIFIED;
115 static int translate_empty_slots __read_mostly = 0;
116 static int calgary_detected __read_mostly = 0;
117
118 /*
119  * the bitmap of PHBs the user requested that we disable
120  * translation on.
121  */
122 static DECLARE_BITMAP(translation_disabled, MAX_NUMNODES * MAX_PHB_BUS_NUM);
123
124 static void tce_cache_blast(struct iommu_table *tbl);
125
126 /* enable this to stress test the chip's TCE cache */
127 #ifdef CONFIG_IOMMU_DEBUG
128 static inline void tce_cache_blast_stress(struct iommu_table *tbl)
129 {
130         tce_cache_blast(tbl);
131 }
132 #else
133 static inline void tce_cache_blast_stress(struct iommu_table *tbl)
134 {
135 }
136 #endif /* BLAST_TCE_CACHE_ON_UNMAP */
137
138 static inline unsigned int num_dma_pages(unsigned long dma, unsigned int dmalen)
139 {
140         unsigned int npages;
141
142         npages = PAGE_ALIGN(dma + dmalen) - (dma & PAGE_MASK);
143         npages >>= PAGE_SHIFT;
144
145         return npages;
146 }
147
148 static inline int translate_phb(struct pci_dev* dev)
149 {
150         int disabled = test_bit(dev->bus->number, translation_disabled);
151         return !disabled;
152 }
153
154 static void iommu_range_reserve(struct iommu_table *tbl,
155         unsigned long start_addr, unsigned int npages)
156 {
157         unsigned long index;
158         unsigned long end;
159
160         index = start_addr >> PAGE_SHIFT;
161
162         /* bail out if we're asked to reserve a region we don't cover */
163         if (index >= tbl->it_size)
164                 return;
165
166         end = index + npages;
167         if (end > tbl->it_size) /* don't go off the table */
168                 end = tbl->it_size;
169
170         while (index < end) {
171                 if (test_bit(index, tbl->it_map))
172                         printk(KERN_ERR "Calgary: entry already allocated at "
173                                "0x%lx tbl %p dma 0x%lx npages %u\n",
174                                index, tbl, start_addr, npages);
175                 ++index;
176         }
177         set_bit_string(tbl->it_map, start_addr >> PAGE_SHIFT, npages);
178 }
179
180 static unsigned long iommu_range_alloc(struct iommu_table *tbl,
181         unsigned int npages)
182 {
183         unsigned long offset;
184
185         BUG_ON(npages == 0);
186
187         offset = find_next_zero_string(tbl->it_map, tbl->it_hint,
188                                        tbl->it_size, npages);
189         if (offset == ~0UL) {
190                 tce_cache_blast(tbl);
191                 offset = find_next_zero_string(tbl->it_map, 0,
192                                                tbl->it_size, npages);
193                 if (offset == ~0UL) {
194                         printk(KERN_WARNING "Calgary: IOMMU full.\n");
195                         if (panic_on_overflow)
196                                 panic("Calgary: fix the allocator.\n");
197                         else
198                                 return bad_dma_address;
199                 }
200         }
201
202         set_bit_string(tbl->it_map, offset, npages);
203         tbl->it_hint = offset + npages;
204         BUG_ON(tbl->it_hint > tbl->it_size);
205
206         return offset;
207 }
208
209 static dma_addr_t iommu_alloc(struct iommu_table *tbl, void *vaddr,
210         unsigned int npages, int direction)
211 {
212         unsigned long entry, flags;
213         dma_addr_t ret = bad_dma_address;
214
215         spin_lock_irqsave(&tbl->it_lock, flags);
216
217         entry = iommu_range_alloc(tbl, npages);
218
219         if (unlikely(entry == bad_dma_address))
220                 goto error;
221
222         /* set the return dma address */
223         ret = (entry << PAGE_SHIFT) | ((unsigned long)vaddr & ~PAGE_MASK);
224
225         /* put the TCEs in the HW table */
226         tce_build(tbl, entry, npages, (unsigned long)vaddr & PAGE_MASK,
227                   direction);
228
229         spin_unlock_irqrestore(&tbl->it_lock, flags);
230
231         return ret;
232
233 error:
234         spin_unlock_irqrestore(&tbl->it_lock, flags);
235         printk(KERN_WARNING "Calgary: failed to allocate %u pages in "
236                "iommu %p\n", npages, tbl);
237         return bad_dma_address;
238 }
239
240 static void __iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
241         unsigned int npages)
242 {
243         unsigned long entry;
244         unsigned long i;
245
246         entry = dma_addr >> PAGE_SHIFT;
247
248         BUG_ON(entry + npages > tbl->it_size);
249
250         tce_free(tbl, entry, npages);
251
252         for (i = 0; i < npages; ++i) {
253                 if (!test_bit(entry + i, tbl->it_map))
254                         printk(KERN_ERR "Calgary: bit is off at 0x%lx "
255                                "tbl %p dma 0x%Lx entry 0x%lx npages %u\n",
256                                entry + i, tbl, dma_addr, entry, npages);
257         }
258
259         __clear_bit_string(tbl->it_map, entry, npages);
260
261         tce_cache_blast_stress(tbl);
262 }
263
264 static void iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr,
265         unsigned int npages)
266 {
267         unsigned long flags;
268
269         spin_lock_irqsave(&tbl->it_lock, flags);
270
271         __iommu_free(tbl, dma_addr, npages);
272
273         spin_unlock_irqrestore(&tbl->it_lock, flags);
274 }
275
276 static void __calgary_unmap_sg(struct iommu_table *tbl,
277         struct scatterlist *sglist, int nelems, int direction)
278 {
279         while (nelems--) {
280                 unsigned int npages;
281                 dma_addr_t dma = sglist->dma_address;
282                 unsigned int dmalen = sglist->dma_length;
283
284                 if (dmalen == 0)
285                         break;
286
287                 npages = num_dma_pages(dma, dmalen);
288                 __iommu_free(tbl, dma, npages);
289                 sglist++;
290         }
291 }
292
293 void calgary_unmap_sg(struct device *dev, struct scatterlist *sglist,
294                       int nelems, int direction)
295 {
296         unsigned long flags;
297         struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
298
299         if (!translate_phb(to_pci_dev(dev)))
300                 return;
301
302         spin_lock_irqsave(&tbl->it_lock, flags);
303
304         __calgary_unmap_sg(tbl, sglist, nelems, direction);
305
306         spin_unlock_irqrestore(&tbl->it_lock, flags);
307 }
308
309 static int calgary_nontranslate_map_sg(struct device* dev,
310         struct scatterlist *sg, int nelems, int direction)
311 {
312         int i;
313
314         for (i = 0; i < nelems; i++ ) {
315                 struct scatterlist *s = &sg[i];
316                 BUG_ON(!s->page);
317                 s->dma_address = virt_to_bus(page_address(s->page) +s->offset);
318                 s->dma_length = s->length;
319         }
320         return nelems;
321 }
322
323 int calgary_map_sg(struct device *dev, struct scatterlist *sg,
324         int nelems, int direction)
325 {
326         struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
327         unsigned long flags;
328         unsigned long vaddr;
329         unsigned int npages;
330         unsigned long entry;
331         int i;
332
333         if (!translate_phb(to_pci_dev(dev)))
334                 return calgary_nontranslate_map_sg(dev, sg, nelems, direction);
335
336         spin_lock_irqsave(&tbl->it_lock, flags);
337
338         for (i = 0; i < nelems; i++ ) {
339                 struct scatterlist *s = &sg[i];
340                 BUG_ON(!s->page);
341
342                 vaddr = (unsigned long)page_address(s->page) + s->offset;
343                 npages = num_dma_pages(vaddr, s->length);
344
345                 entry = iommu_range_alloc(tbl, npages);
346                 if (entry == bad_dma_address) {
347                         /* makes sure unmap knows to stop */
348                         s->dma_length = 0;
349                         goto error;
350                 }
351
352                 s->dma_address = (entry << PAGE_SHIFT) | s->offset;
353
354                 /* insert into HW table */
355                 tce_build(tbl, entry, npages, vaddr & PAGE_MASK,
356                           direction);
357
358                 s->dma_length = s->length;
359         }
360
361         spin_unlock_irqrestore(&tbl->it_lock, flags);
362
363         return nelems;
364 error:
365         __calgary_unmap_sg(tbl, sg, nelems, direction);
366         for (i = 0; i < nelems; i++) {
367                 sg[i].dma_address = bad_dma_address;
368                 sg[i].dma_length = 0;
369         }
370         spin_unlock_irqrestore(&tbl->it_lock, flags);
371         return 0;
372 }
373
374 dma_addr_t calgary_map_single(struct device *dev, void *vaddr,
375         size_t size, int direction)
376 {
377         dma_addr_t dma_handle = bad_dma_address;
378         unsigned long uaddr;
379         unsigned int npages;
380         struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
381
382         uaddr = (unsigned long)vaddr;
383         npages = num_dma_pages(uaddr, size);
384
385         if (translate_phb(to_pci_dev(dev)))
386                 dma_handle = iommu_alloc(tbl, vaddr, npages, direction);
387         else
388                 dma_handle = virt_to_bus(vaddr);
389
390         return dma_handle;
391 }
392
393 void calgary_unmap_single(struct device *dev, dma_addr_t dma_handle,
394         size_t size, int direction)
395 {
396         struct iommu_table *tbl = to_pci_dev(dev)->bus->self->sysdata;
397         unsigned int npages;
398
399         if (!translate_phb(to_pci_dev(dev)))
400                 return;
401
402         npages = num_dma_pages(dma_handle, size);
403         iommu_free(tbl, dma_handle, npages);
404 }
405
406 void* calgary_alloc_coherent(struct device *dev, size_t size,
407         dma_addr_t *dma_handle, gfp_t flag)
408 {
409         void *ret = NULL;
410         dma_addr_t mapping;
411         unsigned int npages, order;
412         struct iommu_table *tbl;
413
414         tbl = to_pci_dev(dev)->bus->self->sysdata;
415
416         size = PAGE_ALIGN(size); /* size rounded up to full pages */
417         npages = size >> PAGE_SHIFT;
418         order = get_order(size);
419
420         /* alloc enough pages (and possibly more) */
421         ret = (void *)__get_free_pages(flag, order);
422         if (!ret)
423                 goto error;
424         memset(ret, 0, size);
425
426         if (translate_phb(to_pci_dev(dev))) {
427                 /* set up tces to cover the allocated range */
428                 mapping = iommu_alloc(tbl, ret, npages, DMA_BIDIRECTIONAL);
429                 if (mapping == bad_dma_address)
430                         goto free;
431
432                 *dma_handle = mapping;
433         } else /* non translated slot */
434                 *dma_handle = virt_to_bus(ret);
435
436         return ret;
437
438 free:
439         free_pages((unsigned long)ret, get_order(size));
440         ret = NULL;
441 error:
442         return ret;
443 }
444
445 static struct dma_mapping_ops calgary_dma_ops = {
446         .alloc_coherent = calgary_alloc_coherent,
447         .map_single = calgary_map_single,
448         .unmap_single = calgary_unmap_single,
449         .map_sg = calgary_map_sg,
450         .unmap_sg = calgary_unmap_sg,
451 };
452
453 static inline int busno_to_phbid(unsigned char num)
454 {
455         return bus_to_phb(num) % PHBS_PER_CALGARY;
456 }
457
458 static inline unsigned long split_queue_offset(unsigned char num)
459 {
460         size_t idx = busno_to_phbid(num);
461
462         return split_queue_offsets[idx];
463 }
464
465 static inline unsigned long tar_offset(unsigned char num)
466 {
467         size_t idx = busno_to_phbid(num);
468
469         return tar_offsets[idx];
470 }
471
472 static inline unsigned long phb_offset(unsigned char num)
473 {
474         size_t idx = busno_to_phbid(num);
475
476         return phb_offsets[idx];
477 }
478
479 static inline void __iomem* calgary_reg(void __iomem *bar, unsigned long offset)
480 {
481         unsigned long target = ((unsigned long)bar) | offset;
482         return (void __iomem*)target;
483 }
484
485 static void tce_cache_blast(struct iommu_table *tbl)
486 {
487         u64 val;
488         u32 aer;
489         int i = 0;
490         void __iomem *bbar = tbl->bbar;
491         void __iomem *target;
492
493         /* disable arbitration on the bus */
494         target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_AER_OFFSET);
495         aer = readl(target);
496         writel(0, target);
497
498         /* read plssr to ensure it got there */
499         target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_PLSSR_OFFSET);
500         val = readl(target);
501
502         /* poll split queues until all DMA activity is done */
503         target = calgary_reg(bbar, split_queue_offset(tbl->it_busno));
504         do {
505                 val = readq(target);
506                 i++;
507         } while ((val & 0xff) != 0xff && i < 100);
508         if (i == 100)
509                 printk(KERN_WARNING "Calgary: PCI bus not quiesced, "
510                        "continuing anyway\n");
511
512         /* invalidate TCE cache */
513         target = calgary_reg(bbar, tar_offset(tbl->it_busno));
514         writeq(tbl->tar_val, target);
515
516         /* enable arbitration */
517         target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_AER_OFFSET);
518         writel(aer, target);
519         (void)readl(target); /* flush */
520 }
521
522 static void __init calgary_reserve_mem_region(struct pci_dev *dev, u64 start,
523         u64 limit)
524 {
525         unsigned int numpages;
526
527         limit = limit | 0xfffff;
528         limit++;
529
530         numpages = ((limit - start) >> PAGE_SHIFT);
531         iommu_range_reserve(dev->sysdata, start, numpages);
532 }
533
534 static void __init calgary_reserve_peripheral_mem_1(struct pci_dev *dev)
535 {
536         void __iomem *target;
537         u64 low, high, sizelow;
538         u64 start, limit;
539         struct iommu_table *tbl = dev->sysdata;
540         unsigned char busnum = dev->bus->number;
541         void __iomem *bbar = tbl->bbar;
542
543         /* peripheral MEM_1 region */
544         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_1_LOW);
545         low = be32_to_cpu(readl(target));
546         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_1_HIGH);
547         high = be32_to_cpu(readl(target));
548         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_1_SIZE);
549         sizelow = be32_to_cpu(readl(target));
550
551         start = (high << 32) | low;
552         limit = sizelow;
553
554         calgary_reserve_mem_region(dev, start, limit);
555 }
556
557 static void __init calgary_reserve_peripheral_mem_2(struct pci_dev *dev)
558 {
559         void __iomem *target;
560         u32 val32;
561         u64 low, high, sizelow, sizehigh;
562         u64 start, limit;
563         struct iommu_table *tbl = dev->sysdata;
564         unsigned char busnum = dev->bus->number;
565         void __iomem *bbar = tbl->bbar;
566
567         /* is it enabled? */
568         target = calgary_reg(bbar, phb_offset(busnum) | PHB_CONFIG_RW_OFFSET);
569         val32 = be32_to_cpu(readl(target));
570         if (!(val32 & PHB_MEM2_ENABLE))
571                 return;
572
573         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_LOW);
574         low = be32_to_cpu(readl(target));
575         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_HIGH);
576         high = be32_to_cpu(readl(target));
577         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_SIZE_LOW);
578         sizelow = be32_to_cpu(readl(target));
579         target = calgary_reg(bbar, phb_offset(busnum) | PHB_MEM_2_SIZE_HIGH);
580         sizehigh = be32_to_cpu(readl(target));
581
582         start = (high << 32) | low;
583         limit = (sizehigh << 32) | sizelow;
584
585         calgary_reserve_mem_region(dev, start, limit);
586 }
587
588 /*
589  * some regions of the IO address space do not get translated, so we
590  * must not give devices IO addresses in those regions. The regions
591  * are the 640KB-1MB region and the two PCI peripheral memory holes.
592  * Reserve all of them in the IOMMU bitmap to avoid giving them out
593  * later.
594  */
595 static void __init calgary_reserve_regions(struct pci_dev *dev)
596 {
597         unsigned int npages;
598         void __iomem *bbar;
599         unsigned char busnum;
600         u64 start;
601         struct iommu_table *tbl = dev->sysdata;
602
603         bbar = tbl->bbar;
604         busnum = dev->bus->number;
605
606         /* reserve bad_dma_address in case it's a legal address */
607         iommu_range_reserve(tbl, bad_dma_address, 1);
608
609         /* avoid the BIOS/VGA first 640KB-1MB region */
610         start = (640 * 1024);
611         npages = ((1024 - 640) * 1024) >> PAGE_SHIFT;
612         iommu_range_reserve(tbl, start, npages);
613
614         /* reserve the two PCI peripheral memory regions in IO space */
615         calgary_reserve_peripheral_mem_1(dev);
616         calgary_reserve_peripheral_mem_2(dev);
617 }
618
619 static int __init calgary_setup_tar(struct pci_dev *dev, void __iomem *bbar)
620 {
621         u64 val64;
622         u64 table_phys;
623         void __iomem *target;
624         int ret;
625         struct iommu_table *tbl;
626
627         /* build TCE tables for each PHB */
628         ret = build_tce_table(dev, bbar);
629         if (ret)
630                 return ret;
631
632         calgary_reserve_regions(dev);
633
634         /* set TARs for each PHB */
635         target = calgary_reg(bbar, tar_offset(dev->bus->number));
636         val64 = be64_to_cpu(readq(target));
637
638         /* zero out all TAR bits under sw control */
639         val64 &= ~TAR_SW_BITS;
640
641         tbl = dev->sysdata;
642         table_phys = (u64)__pa(tbl->it_base);
643         val64 |= table_phys;
644
645         BUG_ON(specified_table_size > TCE_TABLE_SIZE_8M);
646         val64 |= (u64) specified_table_size;
647
648         tbl->tar_val = cpu_to_be64(val64);
649         writeq(tbl->tar_val, target);
650         readq(target); /* flush */
651
652         return 0;
653 }
654
655 static void __init calgary_free_tar(struct pci_dev *dev)
656 {
657         u64 val64;
658         struct iommu_table *tbl = dev->sysdata;
659         void __iomem *target;
660
661         target = calgary_reg(tbl->bbar, tar_offset(dev->bus->number));
662         val64 = be64_to_cpu(readq(target));
663         val64 &= ~TAR_SW_BITS;
664         writeq(cpu_to_be64(val64), target);
665         readq(target); /* flush */
666
667         kfree(tbl);
668         dev->sysdata = NULL;
669 }
670
671 static void calgary_watchdog(unsigned long data)
672 {
673         struct pci_dev *dev = (struct pci_dev *)data;
674         struct iommu_table *tbl = dev->sysdata;
675         void __iomem *bbar = tbl->bbar;
676         u32 val32;
677         void __iomem *target;
678
679         target = calgary_reg(bbar, phb_offset(tbl->it_busno) | PHB_CSR_OFFSET);
680         val32 = be32_to_cpu(readl(target));
681
682         /* If no error, the agent ID in the CSR is not valid */
683         if (val32 & CSR_AGENT_MASK) {
684                 printk(KERN_EMERG "calgary_watchdog: DMA error on bus %d, "
685                                   "CSR = %#x\n", dev->bus->number, val32);
686                 writel(0, target);
687
688                 /* Disable bus that caused the error */
689                 target = calgary_reg(bbar, phb_offset(tbl->it_busno) |
690                                            PHB_CONFIG_RW_OFFSET);
691                 val32 = be32_to_cpu(readl(target));
692                 val32 |= PHB_SLOT_DISABLE;
693                 writel(cpu_to_be32(val32), target);
694                 readl(target); /* flush */
695         } else {
696                 /* Reset the timer */
697                 mod_timer(&tbl->watchdog_timer, jiffies + 2 * HZ);
698         }
699 }
700
701 static void __init calgary_enable_translation(struct pci_dev *dev)
702 {
703         u32 val32;
704         unsigned char busnum;
705         void __iomem *target;
706         void __iomem *bbar;
707         struct iommu_table *tbl;
708
709         busnum = dev->bus->number;
710         tbl = dev->sysdata;
711         bbar = tbl->bbar;
712
713         /* enable TCE in PHB Config Register */
714         target = calgary_reg(bbar, phb_offset(busnum) | PHB_CONFIG_RW_OFFSET);
715         val32 = be32_to_cpu(readl(target));
716         val32 |= PHB_TCE_ENABLE | PHB_DAC_DISABLE | PHB_MCSR_ENABLE;
717
718         printk(KERN_INFO "Calgary: enabling translation on PHB %d\n", busnum);
719         printk(KERN_INFO "Calgary: errant DMAs will now be prevented on this "
720                "bus.\n");
721
722         writel(cpu_to_be32(val32), target);
723         readl(target); /* flush */
724
725         init_timer(&tbl->watchdog_timer);
726         tbl->watchdog_timer.function = &calgary_watchdog;
727         tbl->watchdog_timer.data = (unsigned long)dev;
728         mod_timer(&tbl->watchdog_timer, jiffies);
729 }
730
731 static void __init calgary_disable_translation(struct pci_dev *dev)
732 {
733         u32 val32;
734         unsigned char busnum;
735         void __iomem *target;
736         void __iomem *bbar;
737         struct iommu_table *tbl;
738
739         busnum = dev->bus->number;
740         tbl = dev->sysdata;
741         bbar = tbl->bbar;
742
743         /* disable TCE in PHB Config Register */
744         target = calgary_reg(bbar, phb_offset(busnum) | PHB_CONFIG_RW_OFFSET);
745         val32 = be32_to_cpu(readl(target));
746         val32 &= ~(PHB_TCE_ENABLE | PHB_DAC_DISABLE | PHB_MCSR_ENABLE);
747
748         printk(KERN_INFO "Calgary: disabling translation on PHB %d!\n", busnum);
749         writel(cpu_to_be32(val32), target);
750         readl(target); /* flush */
751
752         del_timer_sync(&tbl->watchdog_timer);
753 }
754
755 static inline unsigned int __init locate_register_space(struct pci_dev *dev)
756 {
757         int rionodeid;
758         u32 address;
759
760         rionodeid = (dev->bus->number % 15 > 4) ? 3 : 2;
761         /*
762          * register space address calculation as follows:
763          * FE0MB-8MB*OneBasedChassisNumber+1MB*(RioNodeId-ChassisBase)
764          * ChassisBase is always zero for x366/x260/x460
765          * RioNodeId is 2 for first Calgary, 3 for second Calgary
766          */
767         address = START_ADDRESS -
768                 (0x800000 * (ONE_BASED_CHASSIS_NUM + dev->bus->number / 15)) +
769                 (0x100000) * (rionodeid - CHASSIS_BASE);
770         return address;
771 }
772
773 static int __init calgary_init_one_nontraslated(struct pci_dev *dev)
774 {
775         dev->sysdata = NULL;
776         dev->bus->self = dev;
777
778         return 0;
779 }
780
781 static int __init calgary_init_one(struct pci_dev *dev)
782 {
783         u32 address;
784         void __iomem *bbar;
785         int ret;
786
787         address = locate_register_space(dev);
788         /* map entire 1MB of Calgary config space */
789         bbar = ioremap_nocache(address, 1024 * 1024);
790         if (!bbar) {
791                 ret = -ENODATA;
792                 goto done;
793         }
794
795         ret = calgary_setup_tar(dev, bbar);
796         if (ret)
797                 goto iounmap;
798
799         dev->bus->self = dev;
800         calgary_enable_translation(dev);
801
802         return 0;
803
804 iounmap:
805         iounmap(bbar);
806 done:
807         return ret;
808 }
809
810 static int __init calgary_init(void)
811 {
812         int i, ret = -ENODEV;
813         struct pci_dev *dev = NULL;
814
815         for (i = 0; i < num_online_nodes() * MAX_NUM_OF_PHBS; i++) {
816                 dev = pci_get_device(PCI_VENDOR_ID_IBM,
817                                      PCI_DEVICE_ID_IBM_CALGARY,
818                                      dev);
819                 if (!dev)
820                         break;
821                 if (!translate_phb(dev)) {
822                         calgary_init_one_nontraslated(dev);
823                         continue;
824                 }
825                 if (!tce_table_kva[i] && !translate_empty_slots) {
826                         pci_dev_put(dev);
827                         continue;
828                 }
829                 ret = calgary_init_one(dev);
830                 if (ret)
831                         goto error;
832         }
833
834         return ret;
835
836 error:
837         for (i--; i >= 0; i--) {
838                 dev = pci_find_device_reverse(PCI_VENDOR_ID_IBM,
839                                               PCI_DEVICE_ID_IBM_CALGARY,
840                                               dev);
841                 if (!translate_phb(dev)) {
842                         pci_dev_put(dev);
843                         continue;
844                 }
845                 if (!tce_table_kva[i] && !translate_empty_slots)
846                         continue;
847                 calgary_disable_translation(dev);
848                 calgary_free_tar(dev);
849                 pci_dev_put(dev);
850         }
851
852         return ret;
853 }
854
855 static inline int __init determine_tce_table_size(u64 ram)
856 {
857         int ret;
858
859         if (specified_table_size != TCE_TABLE_SIZE_UNSPECIFIED)
860                 return specified_table_size;
861
862         /*
863          * Table sizes are from 0 to 7 (TCE_TABLE_SIZE_64K to
864          * TCE_TABLE_SIZE_8M). Table size 0 has 8K entries and each
865          * larger table size has twice as many entries, so shift the
866          * max ram address by 13 to divide by 8K and then look at the
867          * order of the result to choose between 0-7.
868          */
869         ret = get_order(ram >> 13);
870         if (ret > TCE_TABLE_SIZE_8M)
871                 ret = TCE_TABLE_SIZE_8M;
872
873         return ret;
874 }
875
876 void __init detect_calgary(void)
877 {
878         u32 val;
879         int bus, table_idx;
880         void *tbl;
881         int detected = 0;
882
883         /*
884          * if the user specified iommu=off or iommu=soft or we found
885          * another HW IOMMU already, bail out.
886          */
887         if (swiotlb || no_iommu || iommu_detected)
888                 return;
889
890         specified_table_size = determine_tce_table_size(end_pfn * PAGE_SIZE);
891
892         for (bus = 0, table_idx = 0;
893              bus < num_online_nodes() * MAX_PHB_BUS_NUM;
894              bus++) {
895                 if (read_pci_config(bus, 0, 0, 0) != PCI_VENDOR_DEVICE_ID_CALGARY)
896                         continue;
897                 if (test_bit(bus, translation_disabled)) {
898                         printk(KERN_INFO "Calgary: translation is disabled for "
899                                "PHB 0x%x\n", bus);
900                         /* skip this phb, don't allocate a tbl for it */
901                         tce_table_kva[table_idx] = NULL;
902                         table_idx++;
903                         continue;
904                 }
905                 /*
906                  * scan the first slot of the PCI bus to see if there
907                  * are any devices present
908                  */
909                 val = read_pci_config(bus, 1, 0, 0);
910                 if (val != 0xffffffff || translate_empty_slots) {
911                         tbl = alloc_tce_table();
912                         if (!tbl)
913                                 goto cleanup;
914                         detected = 1;
915                 } else
916                         tbl = NULL;
917
918                 tce_table_kva[table_idx] = tbl;
919                 table_idx++;
920         }
921
922         if (detected) {
923                 iommu_detected = 1;
924                 calgary_detected = 1;
925                 printk(KERN_INFO "PCI-DMA: Calgary IOMMU detected. "
926                        "TCE table spec is %d.\n", specified_table_size);
927         }
928         return;
929
930 cleanup:
931         for (--table_idx; table_idx >= 0; --table_idx)
932                 if (tce_table_kva[table_idx])
933                         free_tce_table(tce_table_kva[table_idx]);
934 }
935
936 int __init calgary_iommu_init(void)
937 {
938         int ret;
939
940         if (no_iommu || swiotlb)
941                 return -ENODEV;
942
943         if (!calgary_detected)
944                 return -ENODEV;
945
946         /* ok, we're trying to use Calgary - let's roll */
947         printk(KERN_INFO "PCI-DMA: Using Calgary IOMMU\n");
948
949         ret = calgary_init();
950         if (ret) {
951                 printk(KERN_ERR "PCI-DMA: Calgary init failed %d, "
952                        "falling back to no_iommu\n", ret);
953                 if (end_pfn > MAX_DMA32_PFN)
954                         printk(KERN_ERR "WARNING more than 4GB of memory, "
955                                         "32bit PCI may malfunction.\n");
956                 return ret;
957         }
958
959         force_iommu = 1;
960         dma_ops = &calgary_dma_ops;
961
962         return 0;
963 }
964
965 static int __init calgary_parse_options(char *p)
966 {
967         unsigned int bridge;
968         size_t len;
969         char* endp;
970
971         while (*p) {
972                 if (!strncmp(p, "64k", 3))
973                         specified_table_size = TCE_TABLE_SIZE_64K;
974                 else if (!strncmp(p, "128k", 4))
975                         specified_table_size = TCE_TABLE_SIZE_128K;
976                 else if (!strncmp(p, "256k", 4))
977                         specified_table_size = TCE_TABLE_SIZE_256K;
978                 else if (!strncmp(p, "512k", 4))
979                         specified_table_size = TCE_TABLE_SIZE_512K;
980                 else if (!strncmp(p, "1M", 2))
981                         specified_table_size = TCE_TABLE_SIZE_1M;
982                 else if (!strncmp(p, "2M", 2))
983                         specified_table_size = TCE_TABLE_SIZE_2M;
984                 else if (!strncmp(p, "4M", 2))
985                         specified_table_size = TCE_TABLE_SIZE_4M;
986                 else if (!strncmp(p, "8M", 2))
987                         specified_table_size = TCE_TABLE_SIZE_8M;
988
989                 len = strlen("translate_empty_slots");
990                 if (!strncmp(p, "translate_empty_slots", len))
991                         translate_empty_slots = 1;
992
993                 len = strlen("disable");
994                 if (!strncmp(p, "disable", len)) {
995                         p += len;
996                         if (*p == '=')
997                                 ++p;
998                         if (*p == '\0')
999                                 break;
1000                         bridge = simple_strtol(p, &endp, 0);
1001                         if (p == endp)
1002                                 break;
1003
1004                         if (bridge < (num_online_nodes() * MAX_PHB_BUS_NUM)) {
1005                                 printk(KERN_INFO "Calgary: disabling "
1006                                        "translation for PHB 0x%x\n", bridge);
1007                                 set_bit(bridge, translation_disabled);
1008                         }
1009                 }
1010
1011                 p = strpbrk(p, ",");
1012                 if (!p)
1013                         break;
1014
1015                 p++; /* skip ',' */
1016         }
1017         return 1;
1018 }
1019 __setup("calgary=", calgary_parse_options);