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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
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#include <linux/export.h>
30
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 */
38
39static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
40static unsigned long pcxl_used_bytes __read_mostly = 0;
41static unsigned long pcxl_used_pages __read_mostly = 0;
42
43extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
44static spinlock_t pcxl_res_lock;
45static char *pcxl_res_map;
46static int pcxl_res_hint;
47static 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
61static
62void 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
74static inline void dump_resmap(void) {;}
75#endif
76
77static int pa11_dma_supported( struct device *dev, u64 mask)
78{
79 return 1;
80}
81
82static 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 unsigned long flags;
95
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;
108}
109
110static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
111 unsigned long size, unsigned long *paddr_ptr)
112{
113 unsigned long end;
114 unsigned long orig_vaddr = vaddr;
115
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;
131}
132
133static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
134 unsigned long paddr)
135{
136 pgd_t * dir;
137 unsigned long end = vaddr + size;
138
139 dir = pgd_offset_k(vaddr);
140 do {
141 pmd_t *pmd;
142
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;
152}
153
154static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
155 unsigned long size)
156{
157 pte_t * pte;
158 unsigned long end;
159 unsigned long orig_vaddr = vaddr;
160
161 if (pmd_none(*pmd))
162 return;
163 if (pmd_bad(*pmd)) {
164 pmd_ERROR(*pmd);
165 pmd_clear(pmd);
166 return;
167 }
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;
176
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);
188}
189
190static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
191 unsigned long size)
192{
193 pmd_t * pmd;
194 unsigned long end;
195 unsigned long orig_vaddr = vaddr;
196
197 if (pgd_none(*dir))
198 return;
199 if (pgd_bad(*dir)) {
200 pgd_ERROR(*dir);
201 pgd_clear(dir);
202 return;
203 }
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);
215}
216
217static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
218{
219 pgd_t * dir;
220 unsigned long end = vaddr + size;
221
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));
228}
229
230#define PCXL_SEARCH_LOOP(idx, mask, size) \
231 for(; res_ptr < res_end; ++res_ptr) \
232 { \
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; \
238 } \
239 }
240
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); \
247}
248
249unsigned long
250pcxl_alloc_range(size_t size)
251{
252 int res_idx;
253 u_long mask, flags;
254 unsigned int pages_needed = size >> PAGE_SHIFT;
255
256 mask = (u_long) -1L;
257 mask >>= BITS_PER_LONG - pages_needed;
258
259 DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n",
260 size, pages_needed, mask);
261
262 spin_lock_irqsave(&pcxl_res_lock, flags);
263
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__);
273 }
274
275 dump_resmap();
276 panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
277 __FILE__);
278
279resource_found:
280
281 DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
282 res_idx, mask, pcxl_res_hint);
283
284 pcxl_used_pages += pages_needed;
285 pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
286
287 spin_unlock_irqrestore(&pcxl_res_lock, flags);
288
289 dump_resmap();
290
291 /*
292 ** return the corresponding vaddr in the pcxl dma map
293 */
294 return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
295}
296
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;
301
302/*
303** clear bits in the pcxl resource map
304*/
305static void
306pcxl_free_range(unsigned long vaddr, size_t size)
307{
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;
311
312 mask = (u_long) -1L;
313 mask >>= BITS_PER_LONG - pages_mapped;
314
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);
317
318 spin_lock_irqsave(&pcxl_res_lock, flags);
319
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__);
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
339static int proc_pcxl_dma_show(struct seq_file *m, void *v)
340{
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 */
346
347 seq_printf(m, "\nDMA Mapping Area size : %d bytes (%ld pages)\n",
348 PCXL_DMA_MAP_SIZE, total_pages);
349
350 seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);
351
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);
356
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));
360
361#if 0
362 seq_puts(m, "\nResource bitmap:");
363
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);
368 }
369#endif
370 seq_putc(m, '\n');
371 return 0;
372}
373
374static int proc_pcxl_dma_open(struct inode *inode, struct file *file)
375{
376 return single_open(file, proc_pcxl_dma_show, NULL);
377}
378
379static 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,
385};
386
387static int __init
388pcxl_dma_init(void)
389{
390 if (pcxl_dma_start == 0)
391 return 0;
392
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");
410 }
411 return 0;
412}
413
414__initcall(pcxl_dma_init);
415
416static void *pa11_dma_alloc(struct device *dev, size_t size,
417 dma_addr_t *dma_handle, gfp_t flag, struct dma_attrs *attrs)
418{
419 unsigned long vaddr;
420 unsigned long paddr;
421 int order;
422
423 order = get_order(size);
424 size = 1 << (order + PAGE_SHIFT);
425 vaddr = pcxl_alloc_range(size);
426 paddr = __get_free_pages(flag, order);
427 flush_kernel_dcache_range(paddr, size);
428 paddr = __pa(paddr);
429 map_uncached_pages(vaddr, size, paddr);
430 *dma_handle = (dma_addr_t) paddr;
431
432#if 0
433/* This probably isn't needed to support EISA cards.
434** ISA cards will certainly only support 24-bit DMA addressing.
435** Not clear if we can, want, or need to support ISA.
436*/
437 if (!dev || *dev->coherent_dma_mask < 0xffffffff)
438 gfp |= GFP_DMA;
439#endif
440 return (void *)vaddr;
441}
442
443static void pa11_dma_free(struct device *dev, size_t size, void *vaddr,
444 dma_addr_t dma_handle, struct dma_attrs *attrs)
445{
446 int order;
447
448 order = get_order(size);
449 size = 1 << (order + PAGE_SHIFT);
450 unmap_uncached_pages((unsigned long)vaddr, size);
451 pcxl_free_range((unsigned long)vaddr, size);
452 free_pages((unsigned long)__va(dma_handle), order);
453}
454
455static dma_addr_t pa11_dma_map_page(struct device *dev, struct page *page,
456 unsigned long offset, size_t size,
457 enum dma_data_direction direction, struct dma_attrs *attrs)
458{
459 void *addr = page_address(page) + offset;
460 BUG_ON(direction == DMA_NONE);
461
462 flush_kernel_dcache_range((unsigned long) addr, size);
463 return virt_to_phys(addr);
464}
465
466static void pa11_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
467 size_t size, enum dma_data_direction direction,
468 struct dma_attrs *attrs)
469{
470 BUG_ON(direction == DMA_NONE);
471
472 if (direction == DMA_TO_DEVICE)
473 return;
474
475 /*
476 * For PCI_DMA_FROMDEVICE this flush is not necessary for the
477 * simple map/unmap case. However, it IS necessary if if
478 * pci_dma_sync_single_* has been called and the buffer reused.
479 */
480
481 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
482 return;
483}
484
485static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist,
486 int nents, enum dma_data_direction direction,
487 struct dma_attrs *attrs)
488{
489 int i;
490 struct scatterlist *sg;
491
492 BUG_ON(direction == DMA_NONE);
493
494 for_each_sg(sglist, sg, nents, i) {
495 unsigned long vaddr = (unsigned long)sg_virt(sg);
496
497 sg_dma_address(sg) = (dma_addr_t) virt_to_phys(vaddr);
498 sg_dma_len(sg) = sg->length;
499 flush_kernel_dcache_range(vaddr, sg->length);
500 }
501 return nents;
502}
503
504static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
505 int nents, enum dma_data_direction direction,
506 struct dma_attrs *attrs)
507{
508 int i;
509 struct scatterlist *sg;
510
511 BUG_ON(direction == DMA_NONE);
512
513 if (direction == DMA_TO_DEVICE)
514 return;
515
516 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
517
518 for_each_sg(sglist, sg, nents, i)
519 flush_kernel_vmap_range(sg_virt(sg), sg->length);
520 return;
521}
522
523static void pa11_dma_sync_single_for_cpu(struct device *dev,
524 dma_addr_t dma_handle, size_t size,
525 enum dma_data_direction direction)
526{
527 BUG_ON(direction == DMA_NONE);
528
529 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle),
530 size);
531}
532
533static void pa11_dma_sync_single_for_device(struct device *dev,
534 dma_addr_t dma_handle, size_t size,
535 enum dma_data_direction direction)
536{
537 BUG_ON(direction == DMA_NONE);
538
539 flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle),
540 size);
541}
542
543static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
544{
545 int i;
546 struct scatterlist *sg;
547
548 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
549
550 for_each_sg(sglist, sg, nents, i)
551 flush_kernel_vmap_range(sg_virt(sg), sg->length);
552}
553
554static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
555{
556 int i;
557 struct scatterlist *sg;
558
559 /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
560
561 for_each_sg(sglist, sg, nents, i)
562 flush_kernel_vmap_range(sg_virt(sg), sg->length);
563}
564
565struct dma_map_ops pcxl_dma_ops = {
566 .dma_supported = pa11_dma_supported,
567 .alloc = pa11_dma_alloc,
568 .free = pa11_dma_free,
569 .map_page = pa11_dma_map_page,
570 .unmap_page = pa11_dma_unmap_page,
571 .map_sg = pa11_dma_map_sg,
572 .unmap_sg = pa11_dma_unmap_sg,
573 .sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
574 .sync_single_for_device = pa11_dma_sync_single_for_device,
575 .sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
576 .sync_sg_for_device = pa11_dma_sync_sg_for_device,
577};
578
579static void *pcx_dma_alloc(struct device *dev, size_t size,
580 dma_addr_t *dma_handle, gfp_t flag, struct dma_attrs *attrs)
581{
582 void *addr;
583
584 if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs))
585 return NULL;
586
587 addr = (void *)__get_free_pages(flag, get_order(size));
588 if (addr)
589 *dma_handle = (dma_addr_t)virt_to_phys(addr);
590
591 return addr;
592}
593
594static void pcx_dma_free(struct device *dev, size_t size, void *vaddr,
595 dma_addr_t iova, struct dma_attrs *attrs)
596{
597 free_pages((unsigned long)vaddr, get_order(size));
598 return;
599}
600
601struct dma_map_ops pcx_dma_ops = {
602 .dma_supported = pa11_dma_supported,
603 .alloc = pcx_dma_alloc,
604 .free = pcx_dma_free,
605 .map_page = pa11_dma_map_page,
606 .unmap_page = pa11_dma_unmap_page,
607 .map_sg = pa11_dma_map_sg,
608 .unmap_sg = pa11_dma_unmap_sg,
609 .sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
610 .sync_single_for_device = pa11_dma_sync_single_for_device,
611 .sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
612 .sync_sg_for_device = pa11_dma_sync_sg_for_device,
613};
1// SPDX-License-Identifier: GPL-2.0
2/*
3** PARISC 1.1 Dynamic DMA mapping support.
4** This implementation is for PA-RISC platforms that do not support
5** I/O TLBs (aka DMA address translation hardware).
6** See Documentation/DMA-API-HOWTO.txt for interface definitions.
7**
8** (c) Copyright 1999,2000 Hewlett-Packard Company
9** (c) Copyright 2000 Grant Grundler
10** (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
11** (c) Copyright 2000 John Marvin
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**
18** - ggg
19*/
20
21#include <linux/init.h>
22#include <linux/gfp.h>
23#include <linux/mm.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/dma-direct.h>
29#include <linux/dma-noncoherent.h>
30
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 <linux/uaccess.h>
37#include <asm/tlbflush.h> /* for purge_tlb_*() macros */
38
39static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
40static unsigned long pcxl_used_bytes __read_mostly = 0;
41static unsigned long pcxl_used_pages __read_mostly = 0;
42
43extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
44static DEFINE_SPINLOCK(pcxl_res_lock);
45static char *pcxl_res_map;
46static int pcxl_res_hint;
47static 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
61static
62void 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
74static inline void dump_resmap(void) {;}
75#endif
76
77static inline int map_pte_uncached(pte_t * pte,
78 unsigned long vaddr,
79 unsigned long size, unsigned long *paddr_ptr)
80{
81 unsigned long end;
82 unsigned long orig_vaddr = vaddr;
83
84 vaddr &= ~PMD_MASK;
85 end = vaddr + size;
86 if (end > PMD_SIZE)
87 end = PMD_SIZE;
88 do {
89 unsigned long flags;
90
91 if (!pte_none(*pte))
92 printk(KERN_ERR "map_pte_uncached: page already exists\n");
93 purge_tlb_start(flags);
94 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
95 pdtlb_kernel(orig_vaddr);
96 purge_tlb_end(flags);
97 vaddr += PAGE_SIZE;
98 orig_vaddr += PAGE_SIZE;
99 (*paddr_ptr) += PAGE_SIZE;
100 pte++;
101 } while (vaddr < end);
102 return 0;
103}
104
105static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
106 unsigned long size, unsigned long *paddr_ptr)
107{
108 unsigned long end;
109 unsigned long orig_vaddr = vaddr;
110
111 vaddr &= ~PGDIR_MASK;
112 end = vaddr + size;
113 if (end > PGDIR_SIZE)
114 end = PGDIR_SIZE;
115 do {
116 pte_t * pte = pte_alloc_kernel(pmd, vaddr);
117 if (!pte)
118 return -ENOMEM;
119 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
120 return -ENOMEM;
121 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
122 orig_vaddr += PMD_SIZE;
123 pmd++;
124 } while (vaddr < end);
125 return 0;
126}
127
128static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
129 unsigned long paddr)
130{
131 pgd_t * dir;
132 unsigned long end = vaddr + size;
133
134 dir = pgd_offset_k(vaddr);
135 do {
136 pmd_t *pmd;
137
138 pmd = pmd_alloc(NULL, dir, vaddr);
139 if (!pmd)
140 return -ENOMEM;
141 if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
142 return -ENOMEM;
143 vaddr = vaddr + PGDIR_SIZE;
144 dir++;
145 } while (vaddr && (vaddr < end));
146 return 0;
147}
148
149static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
150 unsigned long size)
151{
152 pte_t * pte;
153 unsigned long end;
154 unsigned long orig_vaddr = vaddr;
155
156 if (pmd_none(*pmd))
157 return;
158 if (pmd_bad(*pmd)) {
159 pmd_ERROR(*pmd);
160 pmd_clear(pmd);
161 return;
162 }
163 pte = pte_offset_map(pmd, vaddr);
164 vaddr &= ~PMD_MASK;
165 end = vaddr + size;
166 if (end > PMD_SIZE)
167 end = PMD_SIZE;
168 do {
169 unsigned long flags;
170 pte_t page = *pte;
171
172 pte_clear(&init_mm, vaddr, pte);
173 purge_tlb_start(flags);
174 pdtlb_kernel(orig_vaddr);
175 purge_tlb_end(flags);
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
185static 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
212static 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
244unsigned long
245pcxl_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
274resource_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*/
300static void
301pcxl_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
334static 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
369static int __init
370pcxl_dma_init(void)
371{
372 if (pcxl_dma_start == 0)
373 return 0;
374
375 pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
376 pcxl_res_hint = 0;
377 pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
378 get_order(pcxl_res_size));
379 memset(pcxl_res_map, 0, pcxl_res_size);
380 proc_gsc_root = proc_mkdir("gsc", NULL);
381 if (!proc_gsc_root)
382 printk(KERN_WARNING
383 "pcxl_dma_init: Unable to create gsc /proc dir entry\n");
384 else {
385 struct proc_dir_entry* ent;
386 ent = proc_create_single("pcxl_dma", 0, proc_gsc_root,
387 proc_pcxl_dma_show);
388 if (!ent)
389 printk(KERN_WARNING
390 "pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
391 }
392 return 0;
393}
394
395__initcall(pcxl_dma_init);
396
397void *arch_dma_alloc(struct device *dev, size_t size,
398 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
399{
400 unsigned long vaddr;
401 unsigned long paddr;
402 int order;
403
404 if (boot_cpu_data.cpu_type != pcxl2 && boot_cpu_data.cpu_type != pcxl)
405 return NULL;
406
407 order = get_order(size);
408 size = 1 << (order + PAGE_SHIFT);
409 vaddr = pcxl_alloc_range(size);
410 paddr = __get_free_pages(gfp | __GFP_ZERO, order);
411 flush_kernel_dcache_range(paddr, size);
412 paddr = __pa(paddr);
413 map_uncached_pages(vaddr, size, paddr);
414 *dma_handle = (dma_addr_t) paddr;
415
416#if 0
417/* This probably isn't needed to support EISA cards.
418** ISA cards will certainly only support 24-bit DMA addressing.
419** Not clear if we can, want, or need to support ISA.
420*/
421 if (!dev || *dev->coherent_dma_mask < 0xffffffff)
422 gfp |= GFP_DMA;
423#endif
424 return (void *)vaddr;
425}
426
427void arch_dma_free(struct device *dev, size_t size, void *vaddr,
428 dma_addr_t dma_handle, unsigned long attrs)
429{
430 int order = get_order(size);
431
432 WARN_ON_ONCE(boot_cpu_data.cpu_type != pcxl2 &&
433 boot_cpu_data.cpu_type != pcxl);
434
435 size = 1 << (order + PAGE_SHIFT);
436 unmap_uncached_pages((unsigned long)vaddr, size);
437 pcxl_free_range((unsigned long)vaddr, size);
438
439 free_pages((unsigned long)__va(dma_handle), order);
440}
441
442void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
443 size_t size, enum dma_data_direction dir)
444{
445 flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
446}
447
448void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
449 size_t size, enum dma_data_direction dir)
450{
451 flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
452}
453
454void arch_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
455 enum dma_data_direction direction)
456{
457 flush_kernel_dcache_range((unsigned long)vaddr, size);
458}