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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/core-api/dma-api-howto.rst 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-map-ops.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 <linux/uaccess.h>
36#include <asm/tlbflush.h> /* for purge_tlb_*() macros */
37
38static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
39static unsigned long pcxl_used_bytes __read_mostly;
40static unsigned long pcxl_used_pages __read_mostly;
41
42unsigned long pcxl_dma_start __ro_after_init; /* pcxl dma mapping area start */
43static DEFINE_SPINLOCK(pcxl_res_lock);
44static char *pcxl_res_map;
45static int pcxl_res_hint;
46static 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
60static
61void 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
73static inline void dump_resmap(void) {;}
74#endif
75
76static inline int map_pte_uncached(pte_t * pte,
77 unsigned long vaddr,
78 unsigned long size, unsigned long *paddr_ptr)
79{
80 unsigned long end;
81 unsigned long orig_vaddr = vaddr;
82
83 vaddr &= ~PMD_MASK;
84 end = vaddr + size;
85 if (end > PMD_SIZE)
86 end = PMD_SIZE;
87 do {
88 unsigned long flags;
89
90 if (!pte_none(*pte))
91 printk(KERN_ERR "map_pte_uncached: page already exists\n");
92 purge_tlb_start(flags);
93 set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
94 pdtlb(SR_KERNEL, orig_vaddr);
95 purge_tlb_end(flags);
96 vaddr += PAGE_SIZE;
97 orig_vaddr += PAGE_SIZE;
98 (*paddr_ptr) += PAGE_SIZE;
99 pte++;
100 } while (vaddr < end);
101 return 0;
102}
103
104static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
105 unsigned long size, unsigned long *paddr_ptr)
106{
107 unsigned long end;
108 unsigned long orig_vaddr = vaddr;
109
110 vaddr &= ~PGDIR_MASK;
111 end = vaddr + size;
112 if (end > PGDIR_SIZE)
113 end = PGDIR_SIZE;
114 do {
115 pte_t * pte = pte_alloc_kernel(pmd, vaddr);
116 if (!pte)
117 return -ENOMEM;
118 if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
119 return -ENOMEM;
120 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
121 orig_vaddr += PMD_SIZE;
122 pmd++;
123 } while (vaddr < end);
124 return 0;
125}
126
127static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
128 unsigned long paddr)
129{
130 pgd_t * dir;
131 unsigned long end = vaddr + size;
132
133 dir = pgd_offset_k(vaddr);
134 do {
135 p4d_t *p4d;
136 pud_t *pud;
137 pmd_t *pmd;
138
139 p4d = p4d_offset(dir, vaddr);
140 pud = pud_offset(p4d, vaddr);
141 pmd = pmd_alloc(NULL, pud, vaddr);
142
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
153static 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_kernel(pmd, vaddr);
168 vaddr &= ~PMD_MASK;
169 end = vaddr + size;
170 if (end > PMD_SIZE)
171 end = PMD_SIZE;
172 do {
173 unsigned long flags;
174 pte_t page = *pte;
175
176 pte_clear(&init_mm, vaddr, pte);
177 purge_tlb_start(flags);
178 pdtlb(SR_KERNEL, orig_vaddr);
179 purge_tlb_end(flags);
180 vaddr += PAGE_SIZE;
181 orig_vaddr += PAGE_SIZE;
182 pte++;
183 if (pte_none(page) || pte_present(page))
184 continue;
185 printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
186 } while (vaddr < end);
187}
188
189static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
190 unsigned long size)
191{
192 pmd_t * pmd;
193 unsigned long end;
194 unsigned long orig_vaddr = vaddr;
195
196 if (pgd_none(*dir))
197 return;
198 if (pgd_bad(*dir)) {
199 pgd_ERROR(*dir);
200 pgd_clear(dir);
201 return;
202 }
203 pmd = pmd_offset(pud_offset(p4d_offset(dir, vaddr), vaddr), vaddr);
204 vaddr &= ~PGDIR_MASK;
205 end = vaddr + size;
206 if (end > PGDIR_SIZE)
207 end = PGDIR_SIZE;
208 do {
209 unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
210 vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
211 orig_vaddr += PMD_SIZE;
212 pmd++;
213 } while (vaddr < end);
214}
215
216static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
217{
218 pgd_t * dir;
219 unsigned long end = vaddr + size;
220
221 dir = pgd_offset_k(vaddr);
222 do {
223 unmap_uncached_pmd(dir, vaddr, end - vaddr);
224 vaddr = vaddr + PGDIR_SIZE;
225 dir++;
226 } while (vaddr && (vaddr < end));
227}
228
229#define PCXL_SEARCH_LOOP(idx, mask, size) \
230 for(; res_ptr < res_end; ++res_ptr) \
231 { \
232 if(0 == ((*res_ptr) & mask)) { \
233 *res_ptr |= mask; \
234 idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
235 pcxl_res_hint = idx + (size >> 3); \
236 goto resource_found; \
237 } \
238 }
239
240#define PCXL_FIND_FREE_MAPPING(idx, mask, size) { \
241 u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
242 u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
243 PCXL_SEARCH_LOOP(idx, mask, size); \
244 res_ptr = (u##size *)&pcxl_res_map[0]; \
245 PCXL_SEARCH_LOOP(idx, mask, size); \
246}
247
248static unsigned long
249pcxl_alloc_range(size_t size)
250{
251 int res_idx;
252 u_long mask, flags;
253 unsigned int pages_needed = size >> 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("%s: pcxl_alloc_range() Too many pages to map.\n",
271 __FILE__);
272 }
273
274 dump_resmap();
275 panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
276 __FILE__);
277
278resource_found:
279
280 DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
281 res_idx, mask, pcxl_res_hint);
282
283 pcxl_used_pages += pages_needed;
284 pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
285
286 spin_unlock_irqrestore(&pcxl_res_lock, flags);
287
288 dump_resmap();
289
290 /*
291 ** return the corresponding vaddr in the pcxl dma map
292 */
293 return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
294}
295
296#define PCXL_FREE_MAPPINGS(idx, m, size) \
297 u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
298 /* BUG_ON((*res_ptr & m) != m); */ \
299 *res_ptr &= ~m;
300
301/*
302** clear bits in the pcxl resource map
303*/
304static void
305pcxl_free_range(unsigned long vaddr, size_t size)
306{
307 u_long mask, flags;
308 unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
309 unsigned int pages_mapped = size >> PAGE_SHIFT;
310
311 mask = (u_long) -1L;
312 mask >>= BITS_PER_LONG - pages_mapped;
313
314 DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
315 res_idx, size, pages_mapped, mask);
316
317 spin_lock_irqsave(&pcxl_res_lock, flags);
318
319 if(pages_mapped <= 8) {
320 PCXL_FREE_MAPPINGS(res_idx, mask, 8);
321 } else if(pages_mapped <= 16) {
322 PCXL_FREE_MAPPINGS(res_idx, mask, 16);
323 } else if(pages_mapped <= 32) {
324 PCXL_FREE_MAPPINGS(res_idx, mask, 32);
325 } else {
326 panic("%s: pcxl_free_range() Too many pages to unmap.\n",
327 __FILE__);
328 }
329
330 pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
331 pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
332
333 spin_unlock_irqrestore(&pcxl_res_lock, flags);
334
335 dump_resmap();
336}
337
338static int __maybe_unused proc_pcxl_dma_show(struct seq_file *m, void *v)
339{
340#if 0
341 u_long i = 0;
342 unsigned long *res_ptr = (u_long *)pcxl_res_map;
343#endif
344 unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */
345
346 seq_printf(m, "\nDMA Mapping Area size : %d bytes (%ld pages)\n",
347 PCXL_DMA_MAP_SIZE, total_pages);
348
349 seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);
350
351 seq_puts(m, " total: free: used: % used:\n");
352 seq_printf(m, "blocks %8d %8ld %8ld %8ld%%\n", pcxl_res_size,
353 pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
354 (pcxl_used_bytes * 100) / pcxl_res_size);
355
356 seq_printf(m, "pages %8ld %8ld %8ld %8ld%%\n", total_pages,
357 total_pages - pcxl_used_pages, pcxl_used_pages,
358 (pcxl_used_pages * 100 / total_pages));
359
360#if 0
361 seq_puts(m, "\nResource bitmap:");
362
363 for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
364 if ((i & 7) == 0)
365 seq_puts(m,"\n ");
366 seq_printf(m, "%s %08lx", buf, *res_ptr);
367 }
368#endif
369 seq_putc(m, '\n');
370 return 0;
371}
372
373static int __init
374pcxl_dma_init(void)
375{
376 if (pcxl_dma_start == 0)
377 return 0;
378
379 pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
380 pcxl_res_hint = 0;
381 pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
382 get_order(pcxl_res_size));
383 memset(pcxl_res_map, 0, pcxl_res_size);
384 proc_gsc_root = proc_mkdir("bus/gsc", NULL);
385 if (!proc_gsc_root)
386 printk(KERN_WARNING
387 "pcxl_dma_init: Unable to create gsc /proc dir entry\n");
388 else {
389 struct proc_dir_entry* ent;
390 ent = proc_create_single("pcxl_dma", 0, proc_gsc_root,
391 proc_pcxl_dma_show);
392 if (!ent)
393 printk(KERN_WARNING
394 "pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
395 }
396 return 0;
397}
398
399__initcall(pcxl_dma_init);
400
401void *arch_dma_alloc(struct device *dev, size_t size,
402 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
403{
404 unsigned long vaddr;
405 unsigned long paddr;
406 int order;
407
408 if (boot_cpu_data.cpu_type != pcxl2 && boot_cpu_data.cpu_type != pcxl)
409 return NULL;
410
411 order = get_order(size);
412 size = 1 << (order + PAGE_SHIFT);
413 vaddr = pcxl_alloc_range(size);
414 paddr = __get_free_pages(gfp | __GFP_ZERO, order);
415 flush_kernel_dcache_range(paddr, size);
416 paddr = __pa(paddr);
417 map_uncached_pages(vaddr, size, paddr);
418 *dma_handle = (dma_addr_t) paddr;
419
420 return (void *)vaddr;
421}
422
423void arch_dma_free(struct device *dev, size_t size, void *vaddr,
424 dma_addr_t dma_handle, unsigned long attrs)
425{
426 int order = get_order(size);
427
428 WARN_ON_ONCE(boot_cpu_data.cpu_type != pcxl2 &&
429 boot_cpu_data.cpu_type != pcxl);
430
431 size = 1 << (order + PAGE_SHIFT);
432 unmap_uncached_pages((unsigned long)vaddr, size);
433 pcxl_free_range((unsigned long)vaddr, size);
434
435 free_pages((unsigned long)__va(dma_handle), order);
436}
437
438void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
439 enum dma_data_direction dir)
440{
441 /*
442 * fdc: The data cache line is written back to memory, if and only if
443 * it is dirty, and then invalidated from the data cache.
444 */
445 flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
446}
447
448void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
449 enum dma_data_direction dir)
450{
451 unsigned long addr = (unsigned long) phys_to_virt(paddr);
452
453 switch (dir) {
454 case DMA_TO_DEVICE:
455 case DMA_BIDIRECTIONAL:
456 flush_kernel_dcache_range(addr, size);
457 return;
458 case DMA_FROM_DEVICE:
459 purge_kernel_dcache_range_asm(addr, addr + size);
460 return;
461 default:
462 BUG();
463 }
464}