Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6/libata-dev.git] / arch / parisc / kernel / pci-dma.c
blobd87d1c476d851c233b02580beaffbb25cc22eb1a
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-API-HOWTO.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
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)
15 ** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
17 ** - ggg
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 #include <linux/export.h>
31 #include <asm/cacheflush.h>
32 #include <asm/dma.h> /* for DMA_CHUNK_SIZE */
33 #include <asm/io.h>
34 #include <asm/page.h> /* get_order */
35 #include <asm/pgalloc.h>
36 #include <asm/uaccess.h>
37 #include <asm/tlbflush.h> /* for purge_tlb_*() macros */
39 static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
40 static unsigned long pcxl_used_bytes __read_mostly = 0;
41 static unsigned long pcxl_used_pages __read_mostly = 0;
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;
49 #ifdef DEBUG_PCXL_RESOURCE
50 #define DBG_RES(x...) printk(x)
51 #else
52 #define DBG_RES(x...)
53 #endif
57 ** Dump a hex representation of the resource map.
60 #ifdef DUMP_RESMAP
61 static
62 void dump_resmap(void)
64 u_long *res_ptr = (unsigned long *)pcxl_res_map;
65 u_long i = 0;
67 printk("res_map: ");
68 for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
69 printk("%08lx ", *res_ptr);
71 printk("\n");
73 #else
74 static inline void dump_resmap(void) {;}
75 #endif
77 static int pa11_dma_supported( struct device *dev, u64 mask)
79 return 1;
82 static inline int map_pte_uncached(pte_t * pte,
83 unsigned long vaddr,
84 unsigned long size, unsigned long *paddr_ptr)
86 unsigned long end;
87 unsigned long orig_vaddr = vaddr;
89 vaddr &= ~PMD_MASK;
90 end = vaddr + size;
91 if (end > PMD_SIZE)
92 end = PMD_SIZE;
93 do {
94 unsigned long flags;
96 if (!pte_none(*pte))
97 printk(KERN_ERR "map_pte_uncached: page already exists\n");
98 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
99 purge_tlb_start(flags);
100 pdtlb_kernel(orig_vaddr);
101 purge_tlb_end(flags);
102 vaddr += PAGE_SIZE;
103 orig_vaddr += PAGE_SIZE;
104 (*paddr_ptr) += PAGE_SIZE;
105 pte++;
106 } while (vaddr < end);
107 return 0;
110 static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
111 unsigned long size, unsigned long *paddr_ptr)
113 unsigned long end;
114 unsigned long orig_vaddr = vaddr;
116 vaddr &= ~PGDIR_MASK;
117 end = vaddr + size;
118 if (end > PGDIR_SIZE)
119 end = PGDIR_SIZE;
120 do {
121 pte_t * pte = pte_alloc_kernel(pmd, vaddr);
122 if (!pte)
123 return -ENOMEM;
124 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
125 return -ENOMEM;
126 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
127 orig_vaddr += PMD_SIZE;
128 pmd++;
129 } while (vaddr < end);
130 return 0;
133 static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
134 unsigned long paddr)
136 pgd_t * dir;
137 unsigned long end = vaddr + size;
139 dir = pgd_offset_k(vaddr);
140 do {
141 pmd_t *pmd;
143 pmd = pmd_alloc(NULL, dir, vaddr);
144 if (!pmd)
145 return -ENOMEM;
146 if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
147 return -ENOMEM;
148 vaddr = vaddr + PGDIR_SIZE;
149 dir++;
150 } while (vaddr && (vaddr < end));
151 return 0;
154 static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
155 unsigned long size)
157 pte_t * pte;
158 unsigned long end;
159 unsigned long orig_vaddr = vaddr;
161 if (pmd_none(*pmd))
162 return;
163 if (pmd_bad(*pmd)) {
164 pmd_ERROR(*pmd);
165 pmd_clear(pmd);
166 return;
168 pte = pte_offset_map(pmd, vaddr);
169 vaddr &= ~PMD_MASK;
170 end = vaddr + size;
171 if (end > PMD_SIZE)
172 end = PMD_SIZE;
173 do {
174 unsigned long flags;
175 pte_t page = *pte;
177 pte_clear(&init_mm, vaddr, pte);
178 purge_tlb_start(flags);
179 pdtlb_kernel(orig_vaddr);
180 purge_tlb_end(flags);
181 vaddr += PAGE_SIZE;
182 orig_vaddr += PAGE_SIZE;
183 pte++;
184 if (pte_none(page) || pte_present(page))
185 continue;
186 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
187 } while (vaddr < end);
190 static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
191 unsigned long size)
193 pmd_t * pmd;
194 unsigned long end;
195 unsigned long orig_vaddr = vaddr;
197 if (pgd_none(*dir))
198 return;
199 if (pgd_bad(*dir)) {
200 pgd_ERROR(*dir);
201 pgd_clear(dir);
202 return;
204 pmd = pmd_offset(dir, vaddr);
205 vaddr &= ~PGDIR_MASK;
206 end = vaddr + size;
207 if (end > PGDIR_SIZE)
208 end = PGDIR_SIZE;
209 do {
210 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
211 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
212 orig_vaddr += PMD_SIZE;
213 pmd++;
214 } while (vaddr < end);
217 static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
219 pgd_t * dir;
220 unsigned long end = vaddr + size;
222 dir = pgd_offset_k(vaddr);
223 do {
224 unmap_uncached_pmd(dir, vaddr, end - vaddr);
225 vaddr = vaddr + PGDIR_SIZE;
226 dir++;
227 } while (vaddr && (vaddr < end));
230 #define PCXL_SEARCH_LOOP(idx, mask, size) \
231 for(; res_ptr < res_end; ++res_ptr) \
233 if(0 == ((*res_ptr) & mask)) { \
234 *res_ptr |= mask; \
235 idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
236 pcxl_res_hint = idx + (size >> 3); \
237 goto resource_found; \
241 #define PCXL_FIND_FREE_MAPPING(idx, mask, size) { \
242 u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
243 u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
244 PCXL_SEARCH_LOOP(idx, mask, size); \
245 res_ptr = (u##size *)&pcxl_res_map[0]; \
246 PCXL_SEARCH_LOOP(idx, mask, size); \
249 unsigned long
250 pcxl_alloc_range(size_t size)
252 int res_idx;
253 u_long mask, flags;
254 unsigned int pages_needed = size >> PAGE_SHIFT;
256 mask = (u_long) -1L;
257 mask >>= BITS_PER_LONG - pages_needed;
259 DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n",
260 size, pages_needed, mask);
262 spin_lock_irqsave(&pcxl_res_lock, flags);
264 if(pages_needed <= 8) {
265 PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
266 } else if(pages_needed <= 16) {
267 PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
268 } else if(pages_needed <= 32) {
269 PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
270 } else {
271 panic("%s: pcxl_alloc_range() Too many pages to map.\n",
272 __FILE__);
275 dump_resmap();
276 panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
277 __FILE__);
279 resource_found:
281 DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
282 res_idx, mask, pcxl_res_hint);
284 pcxl_used_pages += pages_needed;
285 pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
287 spin_unlock_irqrestore(&pcxl_res_lock, flags);
289 dump_resmap();
292 ** return the corresponding vaddr in the pcxl dma map
294 return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
297 #define PCXL_FREE_MAPPINGS(idx, m, size) \
298 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
299 /* BUG_ON((*res_ptr & m) != m); */ \
300 *res_ptr &= ~m;
303 ** clear bits in the pcxl resource map
305 static void
306 pcxl_free_range(unsigned long vaddr, size_t size)
308 u_long mask, flags;
309 unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
310 unsigned int pages_mapped = size >> PAGE_SHIFT;
312 mask = (u_long) -1L;
313 mask >>= BITS_PER_LONG - pages_mapped;
315 DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
316 res_idx, size, pages_mapped, mask);
318 spin_lock_irqsave(&pcxl_res_lock, flags);
320 if(pages_mapped <= 8) {
321 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
322 } else if(pages_mapped <= 16) {
323 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
324 } else if(pages_mapped <= 32) {
325 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
326 } else {
327 panic("%s: pcxl_free_range() Too many pages to unmap.\n",
328 __FILE__);
331 pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
332 pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
334 spin_unlock_irqrestore(&pcxl_res_lock, flags);
336 dump_resmap();
339 static int proc_pcxl_dma_show(struct seq_file *m, void *v)
341 #if 0
342 u_long i = 0;
343 unsigned long *res_ptr = (u_long *)pcxl_res_map;
344 #endif
345 unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */
347 seq_printf(m, "\nDMA Mapping Area size : %d bytes (%ld pages)\n",
348 PCXL_DMA_MAP_SIZE, total_pages);
350 seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);
352 seq_puts(m, " total: free: used: % used:\n");
353 seq_printf(m, "blocks %8d %8ld %8ld %8ld%%\n", pcxl_res_size,
354 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
355 (pcxl_used_bytes * 100) / pcxl_res_size);
357 seq_printf(m, "pages %8ld %8ld %8ld %8ld%%\n", total_pages,
358 total_pages - pcxl_used_pages, pcxl_used_pages,
359 (pcxl_used_pages * 100 / total_pages));
361 #if 0
362 seq_puts(m, "\nResource bitmap:");
364 for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
365 if ((i & 7) == 0)
366 seq_puts(m,"\n ");
367 seq_printf(m, "%s %08lx", buf, *res_ptr);
369 #endif
370 seq_putc(m, '\n');
371 return 0;
374 static int proc_pcxl_dma_open(struct inode *inode, struct file *file)
376 return single_open(file, proc_pcxl_dma_show, NULL);
379 static const struct file_operations proc_pcxl_dma_ops = {
380 .owner = THIS_MODULE,
381 .open = proc_pcxl_dma_open,
382 .read = seq_read,
383 .llseek = seq_lseek,
384 .release = single_release,
387 static int __init
388 pcxl_dma_init(void)
390 if (pcxl_dma_start == 0)
391 return 0;
393 spin_lock_init(&pcxl_res_lock);
394 pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
395 pcxl_res_hint = 0;
396 pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
397 get_order(pcxl_res_size));
398 memset(pcxl_res_map, 0, pcxl_res_size);
399 proc_gsc_root = proc_mkdir("gsc", NULL);
400 if (!proc_gsc_root)
401 printk(KERN_WARNING
402 "pcxl_dma_init: Unable to create gsc /proc dir entry\n");
403 else {
404 struct proc_dir_entry* ent;
405 ent = proc_create("pcxl_dma", 0, proc_gsc_root,
406 &proc_pcxl_dma_ops);
407 if (!ent)
408 printk(KERN_WARNING
409 "pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
411 return 0;
414 __initcall(pcxl_dma_init);
416 static void * pa11_dma_alloc_consistent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag)
418 unsigned long vaddr;
419 unsigned long paddr;
420 int order;
422 order = get_order(size);
423 size = 1 << (order + PAGE_SHIFT);
424 vaddr = pcxl_alloc_range(size);
425 paddr = __get_free_pages(flag, order);
426 flush_kernel_dcache_range(paddr, size);
427 paddr = __pa(paddr);
428 map_uncached_pages(vaddr, size, paddr);
429 *dma_handle = (dma_addr_t) paddr;
431 #if 0
432 /* This probably isn't needed to support EISA cards.
433 ** ISA cards will certainly only support 24-bit DMA addressing.
434 ** Not clear if we can, want, or need to support ISA.
436 if (!dev || *dev->coherent_dma_mask < 0xffffffff)
437 gfp |= GFP_DMA;
438 #endif
439 return (void *)vaddr;
442 static void pa11_dma_free_consistent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle)
444 int order;
446 order = get_order(size);
447 size = 1 << (order + PAGE_SHIFT);
448 unmap_uncached_pages((unsigned long)vaddr, size);
449 pcxl_free_range((unsigned long)vaddr, size);
450 free_pages((unsigned long)__va(dma_handle), order);
453 static dma_addr_t pa11_dma_map_single(struct device *dev, void *addr, size_t size, enum dma_data_direction direction)
455 BUG_ON(direction == DMA_NONE);
457 flush_kernel_dcache_range((unsigned long) addr, size);
458 return virt_to_phys(addr);
461 static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
463 BUG_ON(direction == DMA_NONE);
465 if (direction == DMA_TO_DEVICE)
466 return;
469 * For PCI_DMA_FROMDEVICE this flush is not necessary for the
470 * simple map/unmap case. However, it IS necessary if if
471 * pci_dma_sync_single_* has been called and the buffer reused.
474 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
475 return;
478 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
480 int i;
482 BUG_ON(direction == DMA_NONE);
484 for (i = 0; i < nents; i++, sglist++ ) {
485 unsigned long vaddr = sg_virt_addr(sglist);
486 sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
487 sg_dma_len(sglist) = sglist->length;
488 flush_kernel_dcache_range(vaddr, sglist->length);
490 return nents;
493 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
495 int i;
497 BUG_ON(direction == DMA_NONE);
499 if (direction == DMA_TO_DEVICE)
500 return;
502 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
504 for (i = 0; i < nents; i++, sglist++ )
505 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
506 return;
509 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)
511 BUG_ON(direction == DMA_NONE);
513 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
516 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)
518 BUG_ON(direction == DMA_NONE);
520 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
523 static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
525 int i;
527 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
529 for (i = 0; i < nents; i++, sglist++ )
530 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
533 static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
535 int i;
537 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
539 for (i = 0; i < nents; i++, sglist++ )
540 flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
543 struct hppa_dma_ops pcxl_dma_ops = {
544 .dma_supported = pa11_dma_supported,
545 .alloc_consistent = pa11_dma_alloc_consistent,
546 .alloc_noncoherent = pa11_dma_alloc_consistent,
547 .free_consistent = pa11_dma_free_consistent,
548 .map_single = pa11_dma_map_single,
549 .unmap_single = pa11_dma_unmap_single,
550 .map_sg = pa11_dma_map_sg,
551 .unmap_sg = pa11_dma_unmap_sg,
552 .dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
553 .dma_sync_single_for_device = pa11_dma_sync_single_for_device,
554 .dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
555 .dma_sync_sg_for_device = pa11_dma_sync_sg_for_device,
558 static void *fail_alloc_consistent(struct device *dev, size_t size,
559 dma_addr_t *dma_handle, gfp_t flag)
561 return NULL;
564 static void *pa11_dma_alloc_noncoherent(struct device *dev, size_t size,
565 dma_addr_t *dma_handle, gfp_t flag)
567 void *addr;
569 addr = (void *)__get_free_pages(flag, get_order(size));
570 if (addr)
571 *dma_handle = (dma_addr_t)virt_to_phys(addr);
573 return addr;
576 static void pa11_dma_free_noncoherent(struct device *dev, size_t size,
577 void *vaddr, dma_addr_t iova)
579 free_pages((unsigned long)vaddr, get_order(size));
580 return;
583 struct hppa_dma_ops pcx_dma_ops = {
584 .dma_supported = pa11_dma_supported,
585 .alloc_consistent = fail_alloc_consistent,
586 .alloc_noncoherent = pa11_dma_alloc_noncoherent,
587 .free_consistent = pa11_dma_free_noncoherent,
588 .map_single = pa11_dma_map_single,
589 .unmap_single = pa11_dma_unmap_single,
590 .map_sg = pa11_dma_map_sg,
591 .unmap_sg = pa11_dma_unmap_sg,
592 .dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
593 .dma_sync_single_for_device = pa11_dma_sync_single_for_device,
594 .dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
595 .dma_sync_sg_for_device = pa11_dma_sync_sg_for_device,