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/types.h>
21 #include <linux/mm.h>
22 #include <linux/string.h>
23 #include <linux/pci.h>
24 #include <linux/init.h>
25
26 #include <linux/slab.h>
27 #include <linux/vmalloc.h>
28
29 #include <asm/uaccess.h>
30 #include <asm/pgalloc.h>
31
32 #include <asm/io.h>
33 #include <asm/page.h> /* get_order */
34 #include <asm/dma.h> /* for DMA_CHUNK_SIZE */
35
36 #include <linux/proc_fs.h>
37
38 static struct proc_dir_entry * proc_gsc_root = NULL;
39 static int pcxl_proc_info(char *buffer, char **start, off_t offset, int length);
40 static unsigned long pcxl_used_bytes = 0;
41 static unsigned long pcxl_used_pages = 0;
42
43 extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
44 static spinlock_t pcxl_res_lock;
45 static char *pcxl_res_map;
46 static int pcxl_res_hint;
47 static int pcxl_res_size;
48
49 #ifdef DEBUG_PCXL_RESOURCE
50 #define DBG_RES(x...) printk(x)
51 #else
52 #define DBG_RES(x...)
53 #endif
54
55
56 /*
57 ** Dump a hex representation of the resource map.
58 */
59
60 #ifdef DUMP_RESMAP
61 static
dump_resmap(void)62 void dump_resmap(void)
63 {
64 u_long *res_ptr = (unsigned long *)pcxl_res_map;
65 u_long i = 0;
66
67 printk("res_map: ");
68 for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
69 printk("%08lx ", *res_ptr);
70
71 printk("\n");
72 }
73 #else
dump_resmap(void)74 static inline void dump_resmap(void) {;}
75 #endif
76
pa11_dma_supported(struct pci_dev * dev,u64 mask)77 static int pa11_dma_supported( struct pci_dev *dev, u64 mask)
78 {
79 return 1;
80 }
81
map_pte_uncached(pte_t * pte,unsigned long vaddr,unsigned long size,unsigned long * paddr_ptr)82 static inline int map_pte_uncached(pte_t * pte,
83 unsigned long vaddr,
84 unsigned long size, unsigned long *paddr_ptr)
85 {
86 unsigned long end;
87 unsigned long orig_vaddr = vaddr;
88
89 vaddr &= ~PMD_MASK;
90 end = vaddr + size;
91 if (end > PMD_SIZE)
92 end = PMD_SIZE;
93 do {
94 if (!pte_none(*pte))
95 printk(KERN_ERR "map_pte_uncached: page already exists\n");
96 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
97 pdtlb_kernel(orig_vaddr);
98 vaddr += PAGE_SIZE;
99 orig_vaddr += PAGE_SIZE;
100 (*paddr_ptr) += PAGE_SIZE;
101 pte++;
102 } while (vaddr < end);
103 return 0;
104 }
105
map_pmd_uncached(pmd_t * pmd,unsigned long vaddr,unsigned long size,unsigned long * paddr_ptr)106 static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
107 unsigned long size, unsigned long *paddr_ptr)
108 {
109 unsigned long end;
110 unsigned long orig_vaddr = vaddr;
111
112 vaddr &= ~PGDIR_MASK;
113 end = vaddr + size;
114 if (end > PGDIR_SIZE)
115 end = PGDIR_SIZE;
116 do {
117 pte_t * pte = pte_alloc(NULL, pmd, vaddr);
118 if (!pte)
119 return -ENOMEM;
120 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
121 return -ENOMEM;
122 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
123 orig_vaddr += PMD_SIZE;
124 pmd++;
125 } while (vaddr < end);
126 return 0;
127 }
128
map_uncached_pages(unsigned long vaddr,unsigned long size,unsigned long paddr)129 static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
130 unsigned long paddr)
131 {
132 pgd_t * dir;
133 unsigned long end = vaddr + size;
134
135 dir = pgd_offset_k(vaddr);
136 do {
137 pmd_t *pmd;
138
139 pmd = pmd_alloc(NULL, dir, vaddr);
140 if (!pmd)
141 return -ENOMEM;
142 if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
143 return -ENOMEM;
144 vaddr = vaddr + PGDIR_SIZE;
145 dir++;
146 } while (vaddr && (vaddr < end));
147 return 0;
148 }
149
unmap_uncached_pte(pmd_t * pmd,unsigned long vaddr,unsigned long size)150 static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
151 unsigned long size)
152 {
153 pte_t * pte;
154 unsigned long end;
155 unsigned long orig_vaddr = vaddr;
156
157 if (pmd_none(*pmd))
158 return;
159 if (pmd_bad(*pmd)) {
160 pmd_ERROR(*pmd);
161 pmd_clear(pmd);
162 return;
163 }
164 pte = pte_offset(pmd, vaddr);
165 vaddr &= ~PMD_MASK;
166 end = vaddr + size;
167 if (end > PMD_SIZE)
168 end = PMD_SIZE;
169 do {
170 pte_t page = *pte;
171 pte_clear(pte);
172 pdtlb_kernel(orig_vaddr);
173 vaddr += PAGE_SIZE;
174 orig_vaddr += PAGE_SIZE;
175 pte++;
176 if (pte_none(page) || pte_present(page))
177 continue;
178 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
179 } while (vaddr < end);
180 }
181
unmap_uncached_pmd(pgd_t * dir,unsigned long vaddr,unsigned long size)182 static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
183 unsigned long size)
184 {
185 pmd_t * pmd;
186 unsigned long end;
187 unsigned long orig_vaddr = vaddr;
188
189 if (pgd_none(*dir))
190 return;
191 if (pgd_bad(*dir)) {
192 pgd_ERROR(*dir);
193 pgd_clear(dir);
194 return;
195 }
196 pmd = pmd_offset(dir, vaddr);
197 vaddr &= ~PGDIR_MASK;
198 end = vaddr + size;
199 if (end > PGDIR_SIZE)
200 end = PGDIR_SIZE;
201 do {
202 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
203 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
204 orig_vaddr += PMD_SIZE;
205 pmd++;
206 } while (vaddr < end);
207 }
208
unmap_uncached_pages(unsigned long vaddr,unsigned long size)209 static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
210 {
211 pgd_t * dir;
212 unsigned long end = vaddr + size;
213
214 dir = pgd_offset_k(vaddr);
215 do {
216 unmap_uncached_pmd(dir, vaddr, end - vaddr);
217 vaddr = vaddr + PGDIR_SIZE;
218 dir++;
219 } while (vaddr && (vaddr < end));
220 }
221
222 #define PCXL_SEARCH_LOOP(idx, mask, size) \
223 for(; res_ptr < res_end; ++res_ptr) \
224 { \
225 if(0 == ((*res_ptr) & mask)) { \
226 *res_ptr |= mask; \
227 idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
228 pcxl_res_hint = idx + (size >> 3); \
229 goto resource_found; \
230 } \
231 }
232
233 #define PCXL_FIND_FREE_MAPPING(idx, mask, size) { \
234 u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
235 u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
236 PCXL_SEARCH_LOOP(idx, mask, size); \
237 res_ptr = (u##size *)&pcxl_res_map[0]; \
238 PCXL_SEARCH_LOOP(idx, mask, size); \
239 }
240
241 unsigned long
pcxl_alloc_range(size_t size)242 pcxl_alloc_range(size_t size)
243 {
244 int res_idx;
245 u_long mask, flags;
246 unsigned int pages_needed = size >> PAGE_SHIFT;
247
248 ASSERT(pages_needed);
249 ASSERT((pages_needed * PAGE_SIZE) < DMA_CHUNK_SIZE);
250 ASSERT(pages_needed < (BITS_PER_LONG - PAGE_SHIFT));
251
252 mask = (u_long) -1L;
253 mask >>= BITS_PER_LONG - pages_needed;
254
255 DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n",
256 size, pages_needed, mask);
257
258 spin_lock_irqsave(&pcxl_res_lock, flags);
259
260 if(pages_needed <= 8) {
261 PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
262 } else if(pages_needed <= 16) {
263 PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
264 } else if(pages_needed <= 32) {
265 PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
266 } else {
267 panic(__FILE__ ": pcxl_alloc_range() Too many pages to map.\n");
268 }
269
270 dump_resmap();
271 panic(__FILE__ ": pcxl_alloc_range() out of dma mapping resources\n");
272
273 resource_found:
274
275 DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
276 res_idx, mask, pcxl_res_hint);
277
278 pcxl_used_pages += pages_needed;
279 pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
280
281 spin_unlock_irqrestore(&pcxl_res_lock, flags);
282
283 dump_resmap();
284
285 /*
286 ** return the corresponding vaddr in the pcxl dma map
287 */
288 return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
289 }
290
291 #define PCXL_FREE_MAPPINGS(idx, m, size) \
292 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
293 ASSERT((*res_ptr & m) == m); \
294 *res_ptr &= ~m;
295
296 /*
297 ** clear bits in the pcxl resource map
298 */
299 static void
pcxl_free_range(unsigned long vaddr,size_t size)300 pcxl_free_range(unsigned long vaddr, size_t size)
301 {
302 u_long mask, flags;
303 unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
304 unsigned int pages_mapped = size >> PAGE_SHIFT;
305
306 ASSERT(pages_mapped);
307 ASSERT((pages_mapped * PAGE_SIZE) < DMA_CHUNK_SIZE);
308 ASSERT(pages_mapped < (BITS_PER_LONG - PAGE_SHIFT));
309
310 mask = (u_long) -1L;
311 mask >>= BITS_PER_LONG - pages_mapped;
312
313 DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
314 res_idx, size, pages_mapped, mask);
315
316 spin_lock_irqsave(&pcxl_res_lock, flags);
317
318 if(pages_mapped <= 8) {
319 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
320 } else if(pages_mapped <= 16) {
321 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
322 } else if(pages_mapped <= 32) {
323 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
324 } else {
325 panic(__FILE__ ": pcxl_free_range() Too many pages to unmap.\n");
326 }
327
328 pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
329 pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
330
331 spin_unlock_irqrestore(&pcxl_res_lock, flags);
332
333 dump_resmap();
334 }
335
336 static int __init
pcxl_dma_init(void)337 pcxl_dma_init(void)
338 {
339 if (pcxl_dma_start == 0)
340 return 0;
341
342 spin_lock_init(&pcxl_res_lock);
343 pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
344 pcxl_res_hint = 0;
345 pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
346 get_order(pcxl_res_size));
347
348 proc_gsc_root = proc_mkdir("gsc", 0);
349 create_proc_info_entry("dino", 0, proc_gsc_root, pcxl_proc_info);
350 return 0;
351 }
352
353 __initcall(pcxl_dma_init);
354
pa11_dma_alloc_consistent(struct pci_dev * hwdev,size_t size,dma_addr_t * dma_handle)355 static void * pa11_dma_alloc_consistent (struct pci_dev *hwdev, size_t size, dma_addr_t *dma_handle)
356 {
357 unsigned long vaddr;
358 unsigned long paddr;
359 int order;
360
361 order = get_order(size);
362 size = 1 << (order + PAGE_SHIFT);
363 vaddr = pcxl_alloc_range(size);
364 paddr = __get_free_pages(GFP_ATOMIC, order);
365 flush_kernel_dcache_range(paddr, size);
366 paddr = __pa(paddr);
367 map_uncached_pages(vaddr, size, paddr);
368 *dma_handle = (dma_addr_t) paddr;
369
370 #if 0
371 /* This probably isn't needed to support EISA cards.
372 ** ISA cards will certainly only support 24-bit DMA addressing.
373 ** Not clear if we can, want, or need to support ISA.
374 */
375 if (!hwdev || hwdev->dma_mask != 0xffffffff)
376 gfp |= GFP_DMA;
377 #endif
378 return (void *)vaddr;
379 }
380
pa11_dma_free_consistent(struct pci_dev * hwdev,size_t size,void * vaddr,dma_addr_t dma_handle)381 static void pa11_dma_free_consistent (struct pci_dev *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
382 {
383 int order;
384
385 order = get_order(size);
386 size = 1 << (order + PAGE_SHIFT);
387 unmap_uncached_pages((unsigned long)vaddr, size);
388 pcxl_free_range((unsigned long)vaddr, size);
389 free_pages((unsigned long)__va(dma_handle), order);
390 }
391
pa11_dma_map_single(struct pci_dev * dev,void * addr,size_t size,int direction)392 static dma_addr_t pa11_dma_map_single(struct pci_dev *dev, void *addr, size_t size, int direction)
393 {
394 if (direction == PCI_DMA_NONE) {
395 printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
396 BUG();
397 }
398
399 flush_kernel_dcache_range((unsigned long) addr, size);
400 return virt_to_phys(addr);
401 }
402
pa11_dma_unmap_single(struct pci_dev * dev,dma_addr_t dma_handle,size_t size,int direction)403 static void pa11_dma_unmap_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
404 {
405 if (direction == PCI_DMA_NONE) {
406 printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
407 BUG();
408 }
409
410 if (direction == PCI_DMA_TODEVICE)
411 return;
412
413 /*
414 * For PCI_DMA_FROMDEVICE this flush is not necessary for the
415 * simple map/unmap case. However, it IS necessary if if
416 * pci_dma_sync_single has been called and the buffer reused.
417 */
418
419 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
420 return;
421 }
422
pa11_dma_map_sg(struct pci_dev * dev,struct scatterlist * sglist,int nents,int direction)423 static int pa11_dma_map_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
424 {
425 int i;
426
427 if (direction == PCI_DMA_NONE)
428 BUG();
429
430 for (i = 0; i < nents; i++, sglist++ ) {
431 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(sg_virt_addr(sglist));
432 sg_dma_len(sglist) = sglist->length;
433 flush_kernel_dcache_range((unsigned long)sg_virt_addr(sglist),
434 sglist->length);
435 }
436 return nents;
437 }
438
pa11_dma_unmap_sg(struct pci_dev * dev,struct scatterlist * sglist,int nents,int direction)439 static void pa11_dma_unmap_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
440 {
441 int i;
442
443 if (direction == PCI_DMA_NONE)
444 BUG();
445
446 if (direction == PCI_DMA_TODEVICE)
447 return;
448
449 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
450
451 for (i = 0; i < nents; i++, sglist++ )
452 flush_kernel_dcache_range((unsigned long) sg_virt_addr(sglist), sglist->length);
453 return;
454 }
455
pa11_dma_sync_single(struct pci_dev * dev,dma_addr_t dma_handle,size_t size,int direction)456 static void pa11_dma_sync_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
457 {
458 if (direction == PCI_DMA_NONE)
459 BUG();
460
461 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
462 }
463
pa11_dma_sync_sg(struct pci_dev * dev,struct scatterlist * sglist,int nents,int direction)464 static void pa11_dma_sync_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
465 {
466 int i;
467
468 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
469
470 for (i = 0; i < nents; i++, sglist++ )
471 flush_kernel_dcache_range((unsigned long) sg_virt_addr(sglist), sglist->length);
472 }
473
474 struct pci_dma_ops pcxl_dma_ops = {
475 pa11_dma_supported, /* dma_support */
476 pa11_dma_alloc_consistent,
477 pa11_dma_free_consistent,
478 pa11_dma_map_single, /* map_single */
479 pa11_dma_unmap_single, /* unmap_single */
480 pa11_dma_map_sg, /* map_sg */
481 pa11_dma_unmap_sg, /* unmap_sg */
482 pa11_dma_sync_single, /* dma_sync_single */
483 pa11_dma_sync_sg /* dma_sync_sg */
484 };
485
fail_alloc_consistent(struct pci_dev * hwdev,size_t size,dma_addr_t * dma_handle)486 static void *fail_alloc_consistent(struct pci_dev *hwdev, size_t size,
487 dma_addr_t *dma_handle)
488 {
489 return NULL;
490 }
491
fail_free_consistent(struct pci_dev * dev,size_t size,void * vaddr,dma_addr_t iova)492 static void fail_free_consistent(struct pci_dev *dev, size_t size,
493 void *vaddr, dma_addr_t iova)
494 {
495 return;
496 }
497
498 struct pci_dma_ops pcx_dma_ops = {
499 pa11_dma_supported, /* dma_support */
500 fail_alloc_consistent,
501 fail_free_consistent,
502 pa11_dma_map_single, /* map_single */
503 pa11_dma_unmap_single, /* unmap_single */
504 pa11_dma_map_sg, /* map_sg */
505 pa11_dma_unmap_sg, /* unmap_sg */
506 pa11_dma_sync_single, /* dma_sync_single */
507 pa11_dma_sync_sg /* dma_sync_sg */
508 };
509
510
pcxl_proc_info(char * buf,char ** start,off_t offset,int len)511 static int pcxl_proc_info(char *buf, char **start, off_t offset, int len)
512 {
513 u_long i = 0;
514 unsigned long *res_ptr = (u_long *)pcxl_res_map;
515 unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */
516
517 sprintf(buf, "\nDMA Mapping Area size : %d bytes (%d pages)\n",
518 PCXL_DMA_MAP_SIZE,
519 (pcxl_res_size << 3) ); /* 1 bit per page */
520
521 sprintf(buf, "%sResource bitmap : %d bytes (%d pages)\n",
522 buf, pcxl_res_size, pcxl_res_size << 3); /* 8 bits per byte */
523
524 strcat(buf, " total: free: used: % used:\n");
525 sprintf(buf, "%sblocks %8d %8ld %8ld %8ld%%\n", buf, pcxl_res_size,
526 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
527 (pcxl_used_bytes * 100) / pcxl_res_size);
528
529 sprintf(buf, "%spages %8ld %8ld %8ld %8ld%%\n", buf, total_pages,
530 total_pages - pcxl_used_pages, pcxl_used_pages,
531 (pcxl_used_pages * 100 / total_pages));
532
533 strcat(buf, "\nResource bitmap:");
534
535 for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
536 if ((i & 7) == 0)
537 strcat(buf,"\n ");
538 sprintf(buf, "%s %08lx", buf, *res_ptr);
539 }
540 strcat(buf, "\n");
541 return strlen(buf);
542 }
543
544