]> nv-tegra.nvidia Code Review - linux-2.6.git/blob - arch/parisc/kernel/pci-dma.c
Merge branch 'bkl/procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic...
[linux-2.6.git] / arch / parisc / kernel / pci-dma.c
1 /*
2 ** PARISC 1.1 Dynamic DMA mapping support.
3 ** This implementation is for PA-RISC platforms that do not support
4 ** I/O TLBs (aka DMA address translation hardware).
5 ** See Documentation/PCI/PCI-DMA-mapping.txt for interface definitions.
6 **
7 **      (c) Copyright 1999,2000 Hewlett-Packard Company
8 **      (c) Copyright 2000 Grant Grundler
9 **      (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
10 **      (c) Copyright 2000 John Marvin
11 **
12 ** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c.
13 ** (I assume it's from David Mosberger-Tang but there was no Copyright)
14 **
15 ** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
16 **
17 ** - ggg
18 */
19
20 #include <linux/init.h>
21 #include <linux/gfp.h>
22 #include <linux/mm.h>
23 #include <linux/pci.h>
24 #include <linux/proc_fs.h>
25 #include <linux/seq_file.h>
26 #include <linux/string.h>
27 #include <linux/types.h>
28 #include <linux/scatterlist.h>
29
30 #include <asm/cacheflush.h>
31 #include <asm/dma.h>    /* for DMA_CHUNK_SIZE */
32 #include <asm/io.h>
33 #include <asm/page.h>   /* get_order */
34 #include <asm/pgalloc.h>
35 #include <asm/uaccess.h>
36 #include <asm/tlbflush.h>       /* for purge_tlb_*() macros */
37
38 static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
39 static unsigned long pcxl_used_bytes __read_mostly = 0;
40 static unsigned long pcxl_used_pages __read_mostly = 0;
41
42 extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
43 static spinlock_t   pcxl_res_lock;
44 static char    *pcxl_res_map;
45 static int     pcxl_res_hint;
46 static int     pcxl_res_size;
47
48 #ifdef DEBUG_PCXL_RESOURCE
49 #define DBG_RES(x...)   printk(x)
50 #else
51 #define DBG_RES(x...)
52 #endif
53
54
55 /*
56 ** Dump a hex representation of the resource map.
57 */
58
59 #ifdef DUMP_RESMAP
60 static
61 void dump_resmap(void)
62 {
63         u_long *res_ptr = (unsigned long *)pcxl_res_map;
64         u_long i = 0;
65
66         printk("res_map: ");
67         for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
68                 printk("%08lx ", *res_ptr);
69
70         printk("\n");
71 }
72 #else
73 static inline void dump_resmap(void) {;}
74 #endif
75
76 static int pa11_dma_supported( struct device *dev, u64 mask)
77 {
78         return 1;
79 }
80
81 static inline int map_pte_uncached(pte_t * pte,
82                 unsigned long vaddr,
83                 unsigned long size, unsigned long *paddr_ptr)
84 {
85         unsigned long end;
86         unsigned long orig_vaddr = vaddr;
87
88         vaddr &= ~PMD_MASK;
89         end = vaddr + size;
90         if (end > PMD_SIZE)
91                 end = PMD_SIZE;
92         do {
93                 unsigned long flags;
94
95                 if (!pte_none(*pte))
96                         printk(KERN_ERR "map_pte_uncached: page already exists\n");
97                 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
98                 purge_tlb_start(flags);
99                 pdtlb_kernel(orig_vaddr);
100                 purge_tlb_end(flags);
101                 vaddr += PAGE_SIZE;
102                 orig_vaddr += PAGE_SIZE;
103                 (*paddr_ptr) += PAGE_SIZE;
104                 pte++;
105         } while (vaddr < end);
106         return 0;
107 }
108
109 static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
110                 unsigned long size, unsigned long *paddr_ptr)
111 {
112         unsigned long end;
113         unsigned long orig_vaddr = vaddr;
114
115         vaddr &= ~PGDIR_MASK;
116         end = vaddr + size;
117         if (end > PGDIR_SIZE)
118                 end = PGDIR_SIZE;
119         do {
120                 pte_t * pte = pte_alloc_kernel(pmd, vaddr);
121                 if (!pte)
122                         return -ENOMEM;
123                 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
124                         return -ENOMEM;
125                 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
126                 orig_vaddr += PMD_SIZE;
127                 pmd++;
128         } while (vaddr < end);
129         return 0;
130 }
131
132 static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
133                 unsigned long paddr)
134 {
135         pgd_t * dir;
136         unsigned long end = vaddr + size;
137
138         dir = pgd_offset_k(vaddr);
139         do {
140                 pmd_t *pmd;
141                 
142                 pmd = pmd_alloc(NULL, dir, vaddr);
143                 if (!pmd)
144                         return -ENOMEM;
145                 if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
146                         return -ENOMEM;
147                 vaddr = vaddr + PGDIR_SIZE;
148                 dir++;
149         } while (vaddr && (vaddr < end));
150         return 0;
151 }
152
153 static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
154                 unsigned long size)
155 {
156         pte_t * pte;
157         unsigned long end;
158         unsigned long orig_vaddr = vaddr;
159
160         if (pmd_none(*pmd))
161                 return;
162         if (pmd_bad(*pmd)) {
163                 pmd_ERROR(*pmd);
164                 pmd_clear(pmd);
165                 return;
166         }
167         pte = pte_offset_map(pmd, vaddr);
168         vaddr &= ~PMD_MASK;
169         end = vaddr + size;
170         if (end > PMD_SIZE)
171                 end = PMD_SIZE;
172         do {
173                 unsigned long flags;
174                 pte_t page = *pte;
175
176                 pte_clear(&init_mm, vaddr, pte);
177                 purge_tlb_start(flags);
178                 pdtlb_kernel(orig_vaddr);
179                 purge_tlb_end(flags);
180                 vaddr += PAGE_SIZE;
181                 orig_vaddr += PAGE_SIZE;
182                 pte++;
183                 if (pte_none(page) || pte_present(page))
184                         continue;
185                 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
186         } while (vaddr < end);
187 }
188
189 static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
190                 unsigned long size)
191 {
192         pmd_t * pmd;
193         unsigned long end;
194         unsigned long orig_vaddr = vaddr;
195
196         if (pgd_none(*dir))
197                 return;
198         if (pgd_bad(*dir)) {
199                 pgd_ERROR(*dir);
200                 pgd_clear(dir);
201                 return;
202         }
203         pmd = pmd_offset(dir, vaddr);
204         vaddr &= ~PGDIR_MASK;
205         end = vaddr + size;
206         if (end > PGDIR_SIZE)
207                 end = PGDIR_SIZE;
208         do {
209                 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
210                 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
211                 orig_vaddr += PMD_SIZE;
212                 pmd++;
213         } while (vaddr < end);
214 }
215
216 static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
217 {
218         pgd_t * dir;
219         unsigned long end = vaddr + size;
220
221         dir = pgd_offset_k(vaddr);
222         do {
223                 unmap_uncached_pmd(dir, vaddr, end - vaddr);
224                 vaddr = vaddr + PGDIR_SIZE;
225                 dir++;
226         } while (vaddr && (vaddr < end));
227 }
228
229 #define PCXL_SEARCH_LOOP(idx, mask, size)  \
230        for(; res_ptr < res_end; ++res_ptr) \
231        { \
232                if(0 == ((*res_ptr) & mask)) { \
233                        *res_ptr |= mask; \
234                        idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
235                        pcxl_res_hint = idx + (size >> 3); \
236                        goto resource_found; \
237                } \
238        }
239
240 #define PCXL_FIND_FREE_MAPPING(idx, mask, size)  { \
241        u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
242        u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
243        PCXL_SEARCH_LOOP(idx, mask, size); \
244        res_ptr = (u##size *)&pcxl_res_map[0]; \
245        PCXL_SEARCH_LOOP(idx, mask, size); \
246 }
247
248 unsigned long
249 pcxl_alloc_range(size_t size)
250 {
251         int res_idx;
252         u_long mask, flags;
253         unsigned int pages_needed = size >> PAGE_SHIFT;
254
255         mask = (u_long) -1L;
256         mask >>= BITS_PER_LONG - pages_needed;
257
258         DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n", 
259                 size, pages_needed, mask);
260
261         spin_lock_irqsave(&pcxl_res_lock, flags);
262
263         if(pages_needed <= 8) {
264                 PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
265         } else if(pages_needed <= 16) {
266                 PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
267         } else if(pages_needed <= 32) {
268                 PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
269         } else {
270                 panic("%s: pcxl_alloc_range() Too many pages to map.\n",
271                       __FILE__);
272         }
273
274         dump_resmap();
275         panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
276               __FILE__);
277         
278 resource_found:
279         
280         DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
281                 res_idx, mask, pcxl_res_hint);
282
283         pcxl_used_pages += pages_needed;
284         pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
285
286         spin_unlock_irqrestore(&pcxl_res_lock, flags);
287
288         dump_resmap();
289
290         /* 
291         ** return the corresponding vaddr in the pcxl dma map
292         */
293         return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
294 }
295
296 #define PCXL_FREE_MAPPINGS(idx, m, size) \
297                 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
298                 /* BUG_ON((*res_ptr & m) != m); */ \
299                 *res_ptr &= ~m;
300
301 /*
302 ** clear bits in the pcxl resource map
303 */
304 static void
305 pcxl_free_range(unsigned long vaddr, size_t size)
306 {
307         u_long mask, flags;
308         unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
309         unsigned int pages_mapped = size >> PAGE_SHIFT;
310
311         mask = (u_long) -1L;
312         mask >>= BITS_PER_LONG - pages_mapped;
313
314         DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n", 
315                 res_idx, size, pages_mapped, mask);
316
317         spin_lock_irqsave(&pcxl_res_lock, flags);
318
319         if(pages_mapped <= 8) {
320                 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
321         } else if(pages_mapped <= 16) {
322                 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
323         } else if(pages_mapped <= 32) {
324                 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
325         } else {
326                 panic("%s: pcxl_free_range() Too many pages to unmap.\n",
327                       __FILE__);
328         }
329         
330         pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
331         pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
332
333         spin_unlock_irqrestore(&pcxl_res_lock, flags);
334
335         dump_resmap();
336 }
337
338 static int proc_pcxl_dma_show(struct seq_file *m, void *v)
339 {
340 #if 0
341         u_long i = 0;
342         unsigned long *res_ptr = (u_long *)pcxl_res_map;
343 #endif
344         unsigned long total_pages = pcxl_res_size << 3;   /* 8 bits per byte */
345
346         seq_printf(m, "\nDMA Mapping Area size    : %d bytes (%ld pages)\n",
347                 PCXL_DMA_MAP_SIZE, total_pages);
348
349         seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);
350
351         seq_puts(m,  "            total:    free:    used:   % used:\n");
352         seq_printf(m, "blocks  %8d %8ld %8ld %8ld%%\n", pcxl_res_size,
353                 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
354                 (pcxl_used_bytes * 100) / pcxl_res_size);
355
356         seq_printf(m, "pages   %8ld %8ld %8ld %8ld%%\n", total_pages,
357                 total_pages - pcxl_used_pages, pcxl_used_pages,
358                 (pcxl_used_pages * 100 / total_pages));
359
360 #if 0
361         seq_puts(m, "\nResource bitmap:");
362
363         for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
364                 if ((i & 7) == 0)
365                     seq_puts(m,"\n   ");
366                 seq_printf(m, "%s %08lx", buf, *res_ptr);
367         }
368 #endif
369         seq_putc(m, '\n');
370         return 0;
371 }
372
373 static int proc_pcxl_dma_open(struct inode *inode, struct file *file)
374 {
375         return single_open(file, proc_pcxl_dma_show, NULL);
376 }
377
378 static const struct file_operations proc_pcxl_dma_ops = {
379         .owner          = THIS_MODULE,
380         .open           = proc_pcxl_dma_open,
381         .read           = seq_read,
382         .llseek         = seq_lseek,
383         .release        = single_release,
384 };
385
386 static int __init
387 pcxl_dma_init(void)
388 {
389         if (pcxl_dma_start == 0)
390                 return 0;
391
392         spin_lock_init(&pcxl_res_lock);
393         pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
394         pcxl_res_hint = 0;
395         pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
396                                             get_order(pcxl_res_size));
397         memset(pcxl_res_map, 0, pcxl_res_size);
398         proc_gsc_root = proc_mkdir("gsc", NULL);
399         if (!proc_gsc_root)
400                 printk(KERN_WARNING
401                         "pcxl_dma_init: Unable to create gsc /proc dir entry\n");
402         else {
403                 struct proc_dir_entry* ent;
404                 ent = proc_create("pcxl_dma", 0, proc_gsc_root,
405                                   &proc_pcxl_dma_ops);
406                 if (!ent)
407                         printk(KERN_WARNING
408                                 "pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
409         }
410         return 0;
411 }
412
413 __initcall(pcxl_dma_init);
414
415 static void * pa11_dma_alloc_consistent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag)
416 {
417         unsigned long vaddr;
418         unsigned long paddr;
419         int order;
420
421         order = get_order(size);
422         size = 1 << (order + PAGE_SHIFT);
423         vaddr = pcxl_alloc_range(size);
424         paddr = __get_free_pages(flag, order);
425         flush_kernel_dcache_range(paddr, size);
426         paddr = __pa(paddr);
427         map_uncached_pages(vaddr, size, paddr);
428         *dma_handle = (dma_addr_t) paddr;
429
430 #if 0
431 /* This probably isn't needed to support EISA cards.
432 ** ISA cards will certainly only support 24-bit DMA addressing.
433 ** Not clear if we can, want, or need to support ISA.
434 */
435         if (!dev || *dev->coherent_dma_mask < 0xffffffff)
436                 gfp |= GFP_DMA;
437 #endif
438         return (void *)vaddr;
439 }
440
441 static void pa11_dma_free_consistent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle)
442 {
443         int order;
444
445         order = get_order(size);
446         size = 1 << (order + PAGE_SHIFT);
447         unmap_uncached_pages((unsigned long)vaddr, size);
448         pcxl_free_range((unsigned long)vaddr, size);
449         free_pages((unsigned long)__va(dma_handle), order);
450 }
451
452 static dma_addr_t pa11_dma_map_single(struct device *dev, void *addr, size_t size, enum dma_data_direction direction)
453 {
454         BUG_ON(direction == DMA_NONE);
455
456         flush_kernel_dcache_range((unsigned long) addr, size);
457         return virt_to_phys(addr);
458 }
459
460 static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
461 {
462         BUG_ON(direction == DMA_NONE);
463
464         if (direction == DMA_TO_DEVICE)
465             return;
466
467         /*
468          * For PCI_DMA_FROMDEVICE this flush is not necessary for the
469          * simple map/unmap case. However, it IS necessary if if
470          * pci_dma_sync_single_* has been called and the buffer reused.
471          */
472
473         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
474         return;
475 }
476
477 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
478 {
479         int i;
480
481         BUG_ON(direction == DMA_NONE);
482
483         for (i = 0; i < nents; i++, sglist++ ) {
484                 unsigned long vaddr = sg_virt_addr(sglist);
485                 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
486                 sg_dma_len(sglist) = sglist->length;
487                 flush_kernel_dcache_range(vaddr, sglist->length);
488         }
489         return nents;
490 }
491
492 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
493 {
494         int i;
495
496         BUG_ON(direction == DMA_NONE);
497
498         if (direction == DMA_TO_DEVICE)
499             return;
500
501         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
502
503         for (i = 0; i < nents; i++, sglist++ )
504                 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
505         return;
506 }
507
508 static void pa11_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, enum dma_data_direction direction)
509 {
510         BUG_ON(direction == DMA_NONE);
511
512         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
513 }
514
515 static void pa11_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, unsigned long offset, size_t size, enum dma_data_direction direction)
516 {
517         BUG_ON(direction == DMA_NONE);
518
519         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
520 }
521
522 static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
523 {
524         int i;
525
526         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
527
528         for (i = 0; i < nents; i++, sglist++ )
529                 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
530 }
531
532 static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
533 {
534         int i;
535
536         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
537
538         for (i = 0; i < nents; i++, sglist++ )
539                 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
540 }
541
542 struct hppa_dma_ops pcxl_dma_ops = {
543         .dma_supported =        pa11_dma_supported,
544         .alloc_consistent =     pa11_dma_alloc_consistent,
545         .alloc_noncoherent =    pa11_dma_alloc_consistent,
546         .free_consistent =      pa11_dma_free_consistent,
547         .map_single =           pa11_dma_map_single,
548         .unmap_single =         pa11_dma_unmap_single,
549         .map_sg =               pa11_dma_map_sg,
550         .unmap_sg =             pa11_dma_unmap_sg,
551         .dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
552         .dma_sync_single_for_device = pa11_dma_sync_single_for_device,
553         .dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
554         .dma_sync_sg_for_device = pa11_dma_sync_sg_for_device,
555 };
556
557 static void *fail_alloc_consistent(struct device *dev, size_t size,
558                                    dma_addr_t *dma_handle, gfp_t flag)
559 {
560         return NULL;
561 }
562
563 static void *pa11_dma_alloc_noncoherent(struct device *dev, size_t size,
564                                           dma_addr_t *dma_handle, gfp_t flag)
565 {
566         void *addr;
567
568         addr = (void *)__get_free_pages(flag, get_order(size));
569         if (addr)
570                 *dma_handle = (dma_addr_t)virt_to_phys(addr);
571
572         return addr;
573 }
574
575 static void pa11_dma_free_noncoherent(struct device *dev, size_t size,
576                                         void *vaddr, dma_addr_t iova)
577 {
578         free_pages((unsigned long)vaddr, get_order(size));
579         return;
580 }
581
582 struct hppa_dma_ops pcx_dma_ops = {
583         .dma_supported =        pa11_dma_supported,
584         .alloc_consistent =     fail_alloc_consistent,
585         .alloc_noncoherent =    pa11_dma_alloc_noncoherent,
586         .free_consistent =      pa11_dma_free_noncoherent,
587         .map_single =           pa11_dma_map_single,
588         .unmap_single =         pa11_dma_unmap_single,
589         .map_sg =               pa11_dma_map_sg,
590         .unmap_sg =             pa11_dma_unmap_sg,
591         .dma_sync_single_for_cpu =      pa11_dma_sync_single_for_cpu,
592         .dma_sync_single_for_device =   pa11_dma_sync_single_for_device,
593         .dma_sync_sg_for_cpu =          pa11_dma_sync_sg_for_cpu,
594         .dma_sync_sg_for_device =       pa11_dma_sync_sg_for_device,
595 };