ccd61b9567a6e8f837426961ec1c4de231c517f2
[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/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/mm.h>
22 #include <linux/pci.h>
23 #include <linux/proc_fs.h>
24 #include <linux/seq_file.h>
25 #include <linux/slab.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                 if (!pte_none(*pte))
94                         printk(KERN_ERR "map_pte_uncached: page already exists\n");
95                 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
96                 purge_tlb_start();
97                 pdtlb_kernel(orig_vaddr);
98                 purge_tlb_end();
99                 vaddr += PAGE_SIZE;
100                 orig_vaddr += PAGE_SIZE;
101                 (*paddr_ptr) += PAGE_SIZE;
102                 pte++;
103         } while (vaddr < end);
104         return 0;
105 }
106
107 static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
108                 unsigned long size, unsigned long *paddr_ptr)
109 {
110         unsigned long end;
111         unsigned long orig_vaddr = vaddr;
112
113         vaddr &= ~PGDIR_MASK;
114         end = vaddr + size;
115         if (end > PGDIR_SIZE)
116                 end = PGDIR_SIZE;
117         do {
118                 pte_t * pte = pte_alloc_kernel(pmd, vaddr);
119                 if (!pte)
120                         return -ENOMEM;
121                 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
122                         return -ENOMEM;
123                 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
124                 orig_vaddr += PMD_SIZE;
125                 pmd++;
126         } while (vaddr < end);
127         return 0;
128 }
129
130 static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
131                 unsigned long paddr)
132 {
133         pgd_t * dir;
134         unsigned long end = vaddr + size;
135
136         dir = pgd_offset_k(vaddr);
137         do {
138                 pmd_t *pmd;
139                 
140                 pmd = pmd_alloc(NULL, dir, vaddr);
141                 if (!pmd)
142                         return -ENOMEM;
143                 if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
144                         return -ENOMEM;
145                 vaddr = vaddr + PGDIR_SIZE;
146                 dir++;
147         } while (vaddr && (vaddr < end));
148         return 0;
149 }
150
151 static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
152                 unsigned long size)
153 {
154         pte_t * pte;
155         unsigned long end;
156         unsigned long orig_vaddr = vaddr;
157
158         if (pmd_none(*pmd))
159                 return;
160         if (pmd_bad(*pmd)) {
161                 pmd_ERROR(*pmd);
162                 pmd_clear(pmd);
163                 return;
164         }
165         pte = pte_offset_map(pmd, vaddr);
166         vaddr &= ~PMD_MASK;
167         end = vaddr + size;
168         if (end > PMD_SIZE)
169                 end = PMD_SIZE;
170         do {
171                 pte_t page = *pte;
172                 pte_clear(&init_mm, vaddr, pte);
173                 purge_tlb_start();
174                 pdtlb_kernel(orig_vaddr);
175                 purge_tlb_end();
176                 vaddr += PAGE_SIZE;
177                 orig_vaddr += PAGE_SIZE;
178                 pte++;
179                 if (pte_none(page) || pte_present(page))
180                         continue;
181                 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
182         } while (vaddr < end);
183 }
184
185 static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
186                 unsigned long size)
187 {
188         pmd_t * pmd;
189         unsigned long end;
190         unsigned long orig_vaddr = vaddr;
191
192         if (pgd_none(*dir))
193                 return;
194         if (pgd_bad(*dir)) {
195                 pgd_ERROR(*dir);
196                 pgd_clear(dir);
197                 return;
198         }
199         pmd = pmd_offset(dir, vaddr);
200         vaddr &= ~PGDIR_MASK;
201         end = vaddr + size;
202         if (end > PGDIR_SIZE)
203                 end = PGDIR_SIZE;
204         do {
205                 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
206                 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
207                 orig_vaddr += PMD_SIZE;
208                 pmd++;
209         } while (vaddr < end);
210 }
211
212 static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
213 {
214         pgd_t * dir;
215         unsigned long end = vaddr + size;
216
217         dir = pgd_offset_k(vaddr);
218         do {
219                 unmap_uncached_pmd(dir, vaddr, end - vaddr);
220                 vaddr = vaddr + PGDIR_SIZE;
221                 dir++;
222         } while (vaddr && (vaddr < end));
223 }
224
225 #define PCXL_SEARCH_LOOP(idx, mask, size)  \
226        for(; res_ptr < res_end; ++res_ptr) \
227        { \
228                if(0 == ((*res_ptr) & mask)) { \
229                        *res_ptr |= mask; \
230                        idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
231                        pcxl_res_hint = idx + (size >> 3); \
232                        goto resource_found; \
233                } \
234        }
235
236 #define PCXL_FIND_FREE_MAPPING(idx, mask, size)  { \
237        u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
238        u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
239        PCXL_SEARCH_LOOP(idx, mask, size); \
240        res_ptr = (u##size *)&pcxl_res_map[0]; \
241        PCXL_SEARCH_LOOP(idx, mask, size); \
242 }
243
244 unsigned long
245 pcxl_alloc_range(size_t size)
246 {
247         int res_idx;
248         u_long mask, flags;
249         unsigned int pages_needed = size >> PAGE_SHIFT;
250
251         mask = (u_long) -1L;
252         mask >>= BITS_PER_LONG - pages_needed;
253
254         DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n", 
255                 size, pages_needed, mask);
256
257         spin_lock_irqsave(&pcxl_res_lock, flags);
258
259         if(pages_needed <= 8) {
260                 PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
261         } else if(pages_needed <= 16) {
262                 PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
263         } else if(pages_needed <= 32) {
264                 PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
265         } else {
266                 panic("%s: pcxl_alloc_range() Too many pages to map.\n",
267                       __FILE__);
268         }
269
270         dump_resmap();
271         panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
272               __FILE__);
273         
274 resource_found:
275         
276         DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
277                 res_idx, mask, pcxl_res_hint);
278
279         pcxl_used_pages += pages_needed;
280         pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
281
282         spin_unlock_irqrestore(&pcxl_res_lock, flags);
283
284         dump_resmap();
285
286         /* 
287         ** return the corresponding vaddr in the pcxl dma map
288         */
289         return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
290 }
291
292 #define PCXL_FREE_MAPPINGS(idx, m, size) \
293                 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
294                 /* BUG_ON((*res_ptr & m) != m); */ \
295                 *res_ptr &= ~m;
296
297 /*
298 ** clear bits in the pcxl resource map
299 */
300 static void
301 pcxl_free_range(unsigned long vaddr, size_t size)
302 {
303         u_long mask, flags;
304         unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
305         unsigned int pages_mapped = size >> PAGE_SHIFT;
306
307         mask = (u_long) -1L;
308         mask >>= BITS_PER_LONG - pages_mapped;
309
310         DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n", 
311                 res_idx, size, pages_mapped, mask);
312
313         spin_lock_irqsave(&pcxl_res_lock, flags);
314
315         if(pages_mapped <= 8) {
316                 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
317         } else if(pages_mapped <= 16) {
318                 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
319         } else if(pages_mapped <= 32) {
320                 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
321         } else {
322                 panic("%s: pcxl_free_range() Too many pages to unmap.\n",
323                       __FILE__);
324         }
325         
326         pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
327         pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
328
329         spin_unlock_irqrestore(&pcxl_res_lock, flags);
330
331         dump_resmap();
332 }
333
334 static int proc_pcxl_dma_show(struct seq_file *m, void *v)
335 {
336 #if 0
337         u_long i = 0;
338         unsigned long *res_ptr = (u_long *)pcxl_res_map;
339 #endif
340         unsigned long total_pages = pcxl_res_size << 3;   /* 8 bits per byte */
341
342         seq_printf(m, "\nDMA Mapping Area size    : %d bytes (%ld pages)\n",
343                 PCXL_DMA_MAP_SIZE, total_pages);
344
345         seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);
346
347         seq_puts(m,  "            total:    free:    used:   % used:\n");
348         seq_printf(m, "blocks  %8d %8ld %8ld %8ld%%\n", pcxl_res_size,
349                 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
350                 (pcxl_used_bytes * 100) / pcxl_res_size);
351
352         seq_printf(m, "pages   %8ld %8ld %8ld %8ld%%\n", total_pages,
353                 total_pages - pcxl_used_pages, pcxl_used_pages,
354                 (pcxl_used_pages * 100 / total_pages));
355
356 #if 0
357         seq_puts(m, "\nResource bitmap:");
358
359         for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
360                 if ((i & 7) == 0)
361                     seq_puts(m,"\n   ");
362                 seq_printf(m, "%s %08lx", buf, *res_ptr);
363         }
364 #endif
365         seq_putc(m, '\n');
366         return 0;
367 }
368
369 static int proc_pcxl_dma_open(struct inode *inode, struct file *file)
370 {
371         return single_open(file, proc_pcxl_dma_show, NULL);
372 }
373
374 static const struct file_operations proc_pcxl_dma_ops = {
375         .owner          = THIS_MODULE,
376         .open           = proc_pcxl_dma_open,
377         .read           = seq_read,
378         .llseek         = seq_lseek,
379         .release        = single_release,
380 };
381
382 static int __init
383 pcxl_dma_init(void)
384 {
385         if (pcxl_dma_start == 0)
386                 return 0;
387
388         spin_lock_init(&pcxl_res_lock);
389         pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
390         pcxl_res_hint = 0;
391         pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
392                                             get_order(pcxl_res_size));
393         memset(pcxl_res_map, 0, pcxl_res_size);
394         proc_gsc_root = proc_mkdir("gsc", NULL);
395         if (!proc_gsc_root)
396                 printk(KERN_WARNING
397                         "pcxl_dma_init: Unable to create gsc /proc dir entry\n");
398         else {
399                 struct proc_dir_entry* ent;
400                 ent = proc_create("pcxl_dma", 0, proc_gsc_root,
401                                   &proc_pcxl_dma_ops);
402                 if (!ent)
403                         printk(KERN_WARNING
404                                 "pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
405         }
406         return 0;
407 }
408
409 __initcall(pcxl_dma_init);
410
411 static void * pa11_dma_alloc_consistent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag)
412 {
413         unsigned long vaddr;
414         unsigned long paddr;
415         int order;
416
417         order = get_order(size);
418         size = 1 << (order + PAGE_SHIFT);
419         vaddr = pcxl_alloc_range(size);
420         paddr = __get_free_pages(flag, order);
421         flush_kernel_dcache_range(paddr, size);
422         paddr = __pa(paddr);
423         map_uncached_pages(vaddr, size, paddr);
424         *dma_handle = (dma_addr_t) paddr;
425
426 #if 0
427 /* This probably isn't needed to support EISA cards.
428 ** ISA cards will certainly only support 24-bit DMA addressing.
429 ** Not clear if we can, want, or need to support ISA.
430 */
431         if (!dev || *dev->coherent_dma_mask < 0xffffffff)
432                 gfp |= GFP_DMA;
433 #endif
434         return (void *)vaddr;
435 }
436
437 static void pa11_dma_free_consistent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle)
438 {
439         int order;
440
441         order = get_order(size);
442         size = 1 << (order + PAGE_SHIFT);
443         unmap_uncached_pages((unsigned long)vaddr, size);
444         pcxl_free_range((unsigned long)vaddr, size);
445         free_pages((unsigned long)__va(dma_handle), order);
446 }
447
448 static dma_addr_t pa11_dma_map_single(struct device *dev, void *addr, size_t size, enum dma_data_direction direction)
449 {
450         if (direction == DMA_NONE) {
451                 printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
452                 BUG();
453         }
454
455         flush_kernel_dcache_range((unsigned long) addr, size);
456         return virt_to_phys(addr);
457 }
458
459 static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
460 {
461         if (direction == DMA_NONE) {
462                 printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
463                 BUG();
464         }
465
466         if (direction == DMA_TO_DEVICE)
467             return;
468
469         /*
470          * For PCI_DMA_FROMDEVICE this flush is not necessary for the
471          * simple map/unmap case. However, it IS necessary if if
472          * pci_dma_sync_single_* has been called and the buffer reused.
473          */
474
475         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
476         return;
477 }
478
479 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
480 {
481         int i;
482
483         if (direction == DMA_NONE)
484             BUG();
485
486         for (i = 0; i < nents; i++, sglist++ ) {
487                 unsigned long vaddr = sg_virt_addr(sglist);
488                 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
489                 sg_dma_len(sglist) = sglist->length;
490                 flush_kernel_dcache_range(vaddr, sglist->length);
491         }
492         return nents;
493 }
494
495 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
496 {
497         int i;
498
499         if (direction == DMA_NONE)
500             BUG();
501
502         if (direction == DMA_TO_DEVICE)
503             return;
504
505         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
506
507         for (i = 0; i < nents; i++, sglist++ )
508                 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
509         return;
510 }
511
512 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)
513 {
514         if (direction == DMA_NONE)
515             BUG();
516
517         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
518 }
519
520 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)
521 {
522         if (direction == DMA_NONE)
523             BUG();
524
525         flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
526 }
527
528 static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
529 {
530         int i;
531
532         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
533
534         for (i = 0; i < nents; i++, sglist++ )
535                 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
536 }
537
538 static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
539 {
540         int i;
541
542         /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
543
544         for (i = 0; i < nents; i++, sglist++ )
545                 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
546 }
547
548 struct hppa_dma_ops pcxl_dma_ops = {
549         .dma_supported =        pa11_dma_supported,
550         .alloc_consistent =     pa11_dma_alloc_consistent,
551         .alloc_noncoherent =    pa11_dma_alloc_consistent,
552         .free_consistent =      pa11_dma_free_consistent,
553         .map_single =           pa11_dma_map_single,
554         .unmap_single =         pa11_dma_unmap_single,
555         .map_sg =               pa11_dma_map_sg,
556         .unmap_sg =             pa11_dma_unmap_sg,
557         .dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
558         .dma_sync_single_for_device = pa11_dma_sync_single_for_device,
559         .dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
560         .dma_sync_sg_for_device = pa11_dma_sync_sg_for_device,
561 };
562
563 static void *fail_alloc_consistent(struct device *dev, size_t size,
564                                    dma_addr_t *dma_handle, gfp_t flag)
565 {
566         return NULL;
567 }
568
569 static void *pa11_dma_alloc_noncoherent(struct device *dev, size_t size,
570                                           dma_addr_t *dma_handle, gfp_t flag)
571 {
572         void *addr;
573
574         addr = (void *)__get_free_pages(flag, get_order(size));
575         if (addr)
576                 *dma_handle = (dma_addr_t)virt_to_phys(addr);
577
578         return addr;
579 }
580
581 static void pa11_dma_free_noncoherent(struct device *dev, size_t size,
582                                         void *vaddr, dma_addr_t iova)
583 {
584         free_pages((unsigned long)vaddr, get_order(size));
585         return;
586 }
587
588 struct hppa_dma_ops pcx_dma_ops = {
589         .dma_supported =        pa11_dma_supported,
590         .alloc_consistent =     fail_alloc_consistent,
591         .alloc_noncoherent =    pa11_dma_alloc_noncoherent,
592         .free_consistent =      pa11_dma_free_noncoherent,
593         .map_single =           pa11_dma_map_single,
594         .unmap_single =         pa11_dma_unmap_single,
595         .map_sg =               pa11_dma_map_sg,
596         .unmap_sg =             pa11_dma_unmap_sg,
597         .dma_sync_single_for_cpu =      pa11_dma_sync_single_for_cpu,
598         .dma_sync_single_for_device =   pa11_dma_sync_single_for_device,
599         .dma_sync_sg_for_cpu =          pa11_dma_sync_sg_for_cpu,
600         .dma_sync_sg_for_device =       pa11_dma_sync_sg_for_device,
601 };