File: /usr/src/linux/arch/parisc/kernel/pci-dma.c
1 /*
2 ** Dynamic DMA mapping support.
3 ** See Documentation/DMA-mapping.txt for interface definitions.
4 **
5 ** (c) Copyright 1999,2000 Hewlett-Packard Company
6 ** (c) Copyright 2000 Grant Grundler
7 ** (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
8 ** (c) Copyright 2000 John Marvin
9 **
10 ** This implementation is for PA-RISC platforms that do not support
11 ** I/O TLBs (aka DMA address translation hardware).
12 **
13 ** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c.
14 ** (I assume it's from David Mosberger-Tang but there was no Copyright)
15 **
16 ** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
17 ** All PA2.0 machines but V-class can alias xxx_alloc_consistent()
18 ** to use regular cacheable memory.
19 **
20 ** - ggg
21 */
22
23 #include <linux/types.h>
24 #include <linux/mm.h>
25 #include <linux/string.h>
26 #include <linux/pci.h>
27 #include <linux/init.h>
28
29 #include <linux/slab.h>
30 #include <linux/vmalloc.h>
31
32 #include <asm/uaccess.h>
33 #include <asm/pgalloc.h>
34
35 #include <asm/io.h>
36 #include <asm/page.h> /* get_order */
37 #include <asm/dma.h> /* for DMA_CHUNK_SIZE */
38
39 #include <linux/proc_fs.h>
40
41 static struct proc_dir_entry * proc_gsc_root = NULL;
42 static int pcxl_proc_info(char *buffer, char **start, off_t offset, int length);
43 static unsigned long pcxl_used_bytes = 0;
44 static unsigned long pcxl_used_pages = 0;
45
46 extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
47 static spinlock_t pcxl_res_lock;
48 static char *pcxl_res_map;
49 static int pcxl_res_hint;
50 static int pcxl_res_size;
51
52 #ifdef DEBUG_PCXL_RESOURCE
53 #define DBG_RES(x...) printk(x)
54 #else
55 #define DBG_RES(x...)
56 #endif
57
58
59 /*
60 ** Dump a hex representation of the resource map.
61 */
62
63 #ifdef DUMP_RESMAP
64 static
65 void dump_resmap(void)
66 {
67 u_long *res_ptr = (unsigned long *)pcxl_res_map;
68 u_long i = 0;
69
70 printk("res_map: ");
71 for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
72 printk("%08lx ", *res_ptr);
73
74 printk("\n");
75 }
76 #else
77 static inline void dump_resmap(void) {;}
78 #endif
79
80 static int pa11_dma_supported( struct pci_dev *dev, dma_addr_t mask)
81 {
82 return 1;
83 }
84
85 static inline int map_pte_uncached(pte_t * pte,
86 unsigned long vaddr,
87 unsigned long size, unsigned long *paddr_ptr)
88 {
89 unsigned long end;
90 unsigned long orig_vaddr = vaddr;
91
92 vaddr &= ~PMD_MASK;
93 end = vaddr + size;
94 if (end > PMD_SIZE)
95 end = PMD_SIZE;
96 do {
97 if (!pte_none(*pte))
98 printk(KERN_ERR "map_pte_uncached: page already exists\n");
99 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
100 pdtlb_kernel(orig_vaddr);
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_kernel(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(pmd, vaddr);
168 vaddr &= ~PMD_MASK;
169 end = vaddr + size;
170 if (end > PMD_SIZE)
171 end = PMD_SIZE;
172 do {
173 pte_t page = *pte;
174 pte_clear(pte);
175 pdtlb_kernel(orig_vaddr);
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 ASSERT(pages_needed);
252 ASSERT((pages_needed * PAGE_SIZE) < DMA_CHUNK_SIZE);
253 ASSERT(pages_needed < (BITS_PER_LONG - 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(__FILE__ ": pcxl_alloc_range() Too many pages to map.\n");
271 }
272
273 dump_resmap();
274 panic(__FILE__ ": pcxl_alloc_range() out of dma mapping resources\n");
275
276 resource_found:
277
278 DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
279 res_idx, mask, pcxl_res_hint);
280
281 pcxl_used_pages += pages_needed;
282 pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
283
284 spin_unlock_irqrestore(&pcxl_res_lock, flags);
285
286 dump_resmap();
287
288 /*
289 ** return the corresponding vaddr in the pcxl dma map
290 */
291 return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
292 }
293
294 #define PCXL_FREE_MAPPINGS(idx, m, size) \
295 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
296 ASSERT((*res_ptr & m) == m); \
297 *res_ptr &= ~m;
298
299 /*
300 ** clear bits in the pcxl resource map
301 */
302 static void
303 pcxl_free_range(unsigned long vaddr, size_t size)
304 {
305 u_long mask, flags;
306 unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
307 unsigned int pages_mapped = size >> PAGE_SHIFT;
308
309 ASSERT(pages_mapped);
310 ASSERT((pages_mapped * PAGE_SIZE) < DMA_CHUNK_SIZE);
311 ASSERT(pages_mapped < (BITS_PER_LONG - PAGE_SHIFT));
312
313 mask = (u_long) -1L;
314 mask >>= BITS_PER_LONG - pages_mapped;
315
316 DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
317 res_idx, size, pages_mapped, mask);
318
319 spin_lock_irqsave(&pcxl_res_lock, flags);
320
321 if(pages_mapped <= 8) {
322 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
323 } else if(pages_mapped <= 16) {
324 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
325 } else if(pages_mapped <= 32) {
326 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
327 } else {
328 panic(__FILE__ ": pcxl_free_range() Too many pages to unmap.\n");
329 }
330
331 pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
332 pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
333
334 spin_unlock_irqrestore(&pcxl_res_lock, flags);
335
336 dump_resmap();
337 }
338
339 static int __init
340 pcxl_dma_init(void)
341 {
342 if (pcxl_dma_start == 0)
343 return 0;
344
345 spin_lock_init(&pcxl_res_lock);
346 pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
347 pcxl_res_hint = 0;
348 pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
349 get_order(pcxl_res_size));
350
351 proc_gsc_root = proc_mkdir("gsc", 0);
352 create_proc_info_entry("dino", 0, proc_gsc_root, pcxl_proc_info);
353 return 0;
354 }
355
356 __initcall(pcxl_dma_init);
357
358 static void * pa11_dma_alloc_consistent (struct pci_dev *hwdev, size_t size, dma_addr_t *dma_handle)
359 {
360 unsigned long vaddr;
361 unsigned long paddr;
362 int order;
363
364 order = get_order(size);
365 size = 1 << (order + PAGE_SHIFT);
366 vaddr = pcxl_alloc_range(size);
367 paddr = __get_free_pages(GFP_ATOMIC, order);
368 flush_kernel_dcache_range(paddr, size);
369 paddr = __pa(paddr);
370 map_uncached_pages(vaddr, size, paddr);
371 *dma_handle = (dma_addr_t) paddr;
372
373 #if 0
374 /* This probably isn't needed to support EISA cards.
375 ** ISA cards will certainly only support 24-bit DMA addressing.
376 ** Not clear if we can, want, or need to support ISA.
377 */
378 if (!hwdev || hwdev->dma_mask != 0xffffffff)
379 gfp |= GFP_DMA;
380 #endif
381 return (void *)vaddr;
382 }
383
384 static void pa11_dma_free_consistent (struct pci_dev *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
385 {
386 int order;
387
388 order = get_order(size);
389 size = 1 << (order + PAGE_SHIFT);
390 unmap_uncached_pages((unsigned long)vaddr, size);
391 pcxl_free_range((unsigned long)vaddr, size);
392 free_pages((unsigned long)__va(dma_handle), order);
393 }
394
395 static dma_addr_t pa11_dma_map_single(struct pci_dev *dev, void *addr, size_t size, int direction)
396 {
397 if (direction == PCI_DMA_NONE) {
398 printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
399 BUG();
400 }
401
402 flush_kernel_dcache_range((unsigned long) addr, size);
403 return virt_to_phys(addr);
404 }
405
406 static void pa11_dma_unmap_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
407 {
408 if (direction == PCI_DMA_NONE) {
409 printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
410 BUG();
411 }
412
413 if (direction == PCI_DMA_TODEVICE)
414 return;
415
416 /*
417 * For PCI_DMA_FROMDEVICE this flush is not necessary for the
418 * simple map/unmap case. However, it IS necessary if if
419 * pci_dma_sync_single has been called and the buffer reused.
420 */
421
422 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
423 return;
424 }
425
426 static int pa11_dma_map_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
427 {
428 int i;
429
430 if (direction == PCI_DMA_NONE)
431 BUG();
432
433 for (i = 0; i < nents; i++, sglist++ ) {
434 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(sglist->address);
435 sg_dma_len(sglist) = sglist->length;
436 flush_kernel_dcache_range((unsigned long)sglist->address,
437 sglist->length);
438 }
439 return nents;
440 }
441
442 static void pa11_dma_unmap_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
443 {
444 int i;
445
446 if (direction == PCI_DMA_NONE)
447 BUG();
448
449 if (direction == PCI_DMA_TODEVICE)
450 return;
451
452 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
453
454 for (i = 0; i < nents; i++, sglist++ )
455 flush_kernel_dcache_range((unsigned long) sglist->address, sglist->length);
456 return;
457 }
458
459 static void pa11_dma_sync_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
460 {
461 if (direction == PCI_DMA_NONE)
462 BUG();
463
464 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
465 }
466
467 static void pa11_dma_sync_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
468 {
469 int i;
470
471 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
472
473 for (i = 0; i < nents; i++, sglist++ )
474 flush_kernel_dcache_range((unsigned long) sglist->address, sglist->length);
475 }
476
477 struct pci_dma_ops pcxl_dma_ops = {
478 pa11_dma_supported, /* dma_support */
479 pa11_dma_alloc_consistent,
480 pa11_dma_free_consistent,
481 pa11_dma_map_single, /* map_single */
482 pa11_dma_unmap_single, /* unmap_single */
483 pa11_dma_map_sg, /* map_sg */
484 pa11_dma_unmap_sg, /* unmap_sg */
485 pa11_dma_sync_single, /* dma_sync_single */
486 pa11_dma_sync_sg /* dma_sync_sg */
487 };
488
489 static void *fail_alloc_consistent(struct pci_dev *hwdev, size_t size,
490 dma_addr_t *dma_handle)
491 {
492 return NULL;
493 }
494
495 static void fail_free_consistent(struct pci_dev *dev, size_t size,
496 void *vaddr, dma_addr_t iova)
497 {
498 return;
499 }
500
501 struct pci_dma_ops pcx_dma_ops = {
502 pa11_dma_supported, /* dma_support */
503 fail_alloc_consistent,
504 fail_free_consistent,
505 pa11_dma_map_single, /* map_single */
506 pa11_dma_unmap_single, /* unmap_single */
507 pa11_dma_map_sg, /* map_sg */
508 pa11_dma_unmap_sg, /* unmap_sg */
509 pa11_dma_sync_single, /* dma_sync_single */
510 pa11_dma_sync_sg /* dma_sync_sg */
511 };
512
513 struct pci_dma_ops *hppa_dma_ops;
514
515 static int pcxl_proc_info(char *buf, char **start, off_t offset, int len)
516 {
517 u_long i = 0;
518 unsigned long *res_ptr = (u_long *)pcxl_res_map;
519 unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */
520
521 sprintf(buf, "\nDMA Mapping Area size : %d bytes (%d pages)\n",
522 PCXL_DMA_MAP_SIZE,
523 (pcxl_res_size << 3) ); /* 1 bit per page */
524
525 sprintf(buf, "%sResource bitmap : %d bytes (%d pages)\n",
526 buf, pcxl_res_size, pcxl_res_size << 3); /* 8 bits per byte */
527
528 strcat(buf, " total: free: used: % used:\n");
529 sprintf(buf, "%sblocks %8d %8ld %8ld %8ld%%\n", buf, pcxl_res_size,
530 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
531 (pcxl_used_bytes * 100) / pcxl_res_size);
532
533 sprintf(buf, "%spages %8ld %8ld %8ld %8ld%%\n", buf, total_pages,
534 total_pages - pcxl_used_pages, pcxl_used_pages,
535 (pcxl_used_pages * 100 / total_pages));
536
537 strcat(buf, "\nResource bitmap:");
538
539 for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
540 if ((i & 7) == 0)
541 strcat(buf,"\n ");
542 sprintf(buf, "%s %08lx", buf, *res_ptr);
543 }
544 strcat(buf, "\n");
545 return strlen(buf);
546 }
547
548