summaryrefslogtreecommitdiffstats
path: root/arch/parisc/kernel/pci-dma.c
blob: 0c3aecb85a5ccb344ffe8d0f391f6ebaebbf17a6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
/*
** PARISC 1.1 Dynamic DMA mapping support.
** This implementation is for PA-RISC platforms that do not support
** I/O TLBs (aka DMA address translation hardware).
** See Documentation/DMA-mapping.txt for interface definitions.
**
**      (c) Copyright 1999,2000 Hewlett-Packard Company
**      (c) Copyright 2000 Grant Grundler
**	(c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
**      (c) Copyright 2000 John Marvin
**
** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c.
** (I assume it's from David Mosberger-Tang but there was no Copyright)
**
** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
**
** - ggg
*/

#include <linux/init.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>

#include <asm/cacheflush.h>
#include <asm/dma.h>    /* for DMA_CHUNK_SIZE */
#include <asm/io.h>
#include <asm/page.h>	/* get_order */
#include <asm/pgalloc.h>
#include <asm/uaccess.h>
#include <asm/tlbflush.h>	/* for purge_tlb_*() macros */

static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
static int pcxl_proc_info(char *buffer, char **start, off_t offset, int length);
static unsigned long pcxl_used_bytes __read_mostly = 0;
static unsigned long pcxl_used_pages __read_mostly = 0;

extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
static spinlock_t   pcxl_res_lock;
static char    *pcxl_res_map;
static int     pcxl_res_hint;
static int     pcxl_res_size;

#ifdef DEBUG_PCXL_RESOURCE
#define DBG_RES(x...)	printk(x)
#else
#define DBG_RES(x...)
#endif


/*
** Dump a hex representation of the resource map.
*/

#ifdef DUMP_RESMAP
static
void dump_resmap(void)
{
	u_long *res_ptr = (unsigned long *)pcxl_res_map;
	u_long i = 0;

	printk("res_map: ");
	for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
		printk("%08lx ", *res_ptr);

	printk("\n");
}
#else
static inline void dump_resmap(void) {;}
#endif

static int pa11_dma_supported( struct device *dev, u64 mask)
{
	return 1;
}

static inline int map_pte_uncached(pte_t * pte,
		unsigned long vaddr,
		unsigned long size, unsigned long *paddr_ptr)
{
	unsigned long end;
	unsigned long orig_vaddr = vaddr;

	vaddr &= ~PMD_MASK;
	end = vaddr + size;
	if (end > PMD_SIZE)
		end = PMD_SIZE;
	do {
		if (!pte_none(*pte))
			printk(KERN_ERR "map_pte_uncached: page already exists\n");
		set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
		purge_tlb_start();
		pdtlb_kernel(orig_vaddr);
		purge_tlb_end();
		vaddr += PAGE_SIZE;
		orig_vaddr += PAGE_SIZE;
		(*paddr_ptr) += PAGE_SIZE;
		pte++;
	} while (vaddr < end);
	return 0;
}

static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
		unsigned long size, unsigned long *paddr_ptr)
{
	unsigned long end;
	unsigned long orig_vaddr = vaddr;

	vaddr &= ~PGDIR_MASK;
	end = vaddr + size;
	if (end > PGDIR_SIZE)
		end = PGDIR_SIZE;
	do {
		pte_t * pte = pte_alloc_kernel(pmd, vaddr);
		if (!pte)
			return -ENOMEM;
		if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
			return -ENOMEM;
		vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
		orig_vaddr += PMD_SIZE;
		pmd++;
	} while (vaddr < end);
	return 0;
}

static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
		unsigned long paddr)
{
	pgd_t * dir;
	unsigned long end = vaddr + size;

	dir = pgd_offset_k(vaddr);
	do {
		pmd_t *pmd;
		
		pmd = pmd_alloc(NULL, dir, vaddr);
		if (!pmd)
			return -ENOMEM;
		if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
			return -ENOMEM;
		vaddr = vaddr + PGDIR_SIZE;
		dir++;
	} while (vaddr && (vaddr < end));
	return 0;
}

static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
		unsigned long size)
{
	pte_t * pte;
	unsigned long end;
	unsigned long orig_vaddr = vaddr;

	if (pmd_none(*pmd))
		return;
	if (pmd_bad(*pmd)) {
		pmd_ERROR(*pmd);
		pmd_clear(pmd);
		return;
	}
	pte = pte_offset_map(pmd, vaddr);
	vaddr &= ~PMD_MASK;
	end = vaddr + size;
	if (end > PMD_SIZE)
		end = PMD_SIZE;
	do {
		pte_t page = *pte;
		pte_clear(&init_mm, vaddr, pte);
		purge_tlb_start();
		pdtlb_kernel(orig_vaddr);
		purge_tlb_end();
		vaddr += PAGE_SIZE;
		orig_vaddr += PAGE_SIZE;
		pte++;
		if (pte_none(page) || pte_present(page))
			continue;
		printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
	} while (vaddr < end);
}

static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
		unsigned long size)
{
	pmd_t * pmd;
	unsigned long end;
	unsigned long orig_vaddr = vaddr;

	if (pgd_none(*dir))
		return;
	if (pgd_bad(*dir)) {
		pgd_ERROR(*dir);
		pgd_clear(dir);
		return;
	}
	pmd = pmd_offset(dir, vaddr);
	vaddr &= ~PGDIR_MASK;
	end = vaddr + size;
	if (end > PGDIR_SIZE)
		end = PGDIR_SIZE;
	do {
		unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
		vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
		orig_vaddr += PMD_SIZE;
		pmd++;
	} while (vaddr < end);
}

static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
{
	pgd_t * dir;
	unsigned long end = vaddr + size;

	dir = pgd_offset_k(vaddr);
	do {
		unmap_uncached_pmd(dir, vaddr, end - vaddr);
		vaddr = vaddr + PGDIR_SIZE;
		dir++;
	} while (vaddr && (vaddr < end));
}

#define PCXL_SEARCH_LOOP(idx, mask, size)  \
       for(; res_ptr < res_end; ++res_ptr) \
       { \
               if(0 == ((*res_ptr) & mask)) { \
                       *res_ptr |= mask; \
		       idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
		       pcxl_res_hint = idx + (size >> 3); \
                       goto resource_found; \
               } \
       }

#define PCXL_FIND_FREE_MAPPING(idx, mask, size)  { \
       u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
       u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
       PCXL_SEARCH_LOOP(idx, mask, size); \
       res_ptr = (u##size *)&pcxl_res_map[0]; \
       PCXL_SEARCH_LOOP(idx, mask, size); \
}

unsigned long
pcxl_alloc_range(size_t size)
{
	int res_idx;
	u_long mask, flags;
	unsigned int pages_needed = size >> PAGE_SHIFT;

	mask = (u_long) -1L;
 	mask >>= BITS_PER_LONG - pages_needed;

	DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n", 
		size, pages_needed, mask);

	spin_lock_irqsave(&pcxl_res_lock, flags);

	if(pages_needed <= 8) {
		PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
	} else if(pages_needed <= 16) {
		PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
	} else if(pages_needed <= 32) {
		PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
	} else {
		panic("%s: pcxl_alloc_range() Too many pages to map.\n",
		      __FILE__);
	}

	dump_resmap();
	panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
	      __FILE__);
	
resource_found:
	
	DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
		res_idx, mask, pcxl_res_hint);

	pcxl_used_pages += pages_needed;
	pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);

	spin_unlock_irqrestore(&pcxl_res_lock, flags);

	dump_resmap();

	/* 
	** return the corresponding vaddr in the pcxl dma map
	*/
	return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
}

#define PCXL_FREE_MAPPINGS(idx, m, size) \
		u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
		/* BUG_ON((*res_ptr & m) != m); */ \
		*res_ptr &= ~m;

/*
** clear bits in the pcxl resource map
*/
static void
pcxl_free_range(unsigned long vaddr, size_t size)
{
	u_long mask, flags;
	unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
	unsigned int pages_mapped = size >> PAGE_SHIFT;

	mask = (u_long) -1L;
 	mask >>= BITS_PER_LONG - pages_mapped;

	DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n", 
		res_idx, size, pages_mapped, mask);

	spin_lock_irqsave(&pcxl_res_lock, flags);

	if(pages_mapped <= 8) {
		PCXL_FREE_MAPPINGS(res_idx, mask, 8);
	} else if(pages_mapped <= 16) {
		PCXL_FREE_MAPPINGS(res_idx, mask, 16);
	} else if(pages_mapped <= 32) {
		PCXL_FREE_MAPPINGS(res_idx, mask, 32);
	} else {
		panic("%s: pcxl_free_range() Too many pages to unmap.\n",
		      __FILE__);
	}
	
	pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
	pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);

	spin_unlock_irqrestore(&pcxl_res_lock, flags);

	dump_resmap();
}

static int __init
pcxl_dma_init(void)
{
	if (pcxl_dma_start == 0)
		return 0;

	spin_lock_init(&pcxl_res_lock);
	pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
	pcxl_res_hint = 0;
	pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
					    get_order(pcxl_res_size));
	memset(pcxl_res_map, 0, pcxl_res_size);
	proc_gsc_root = proc_mkdir("gsc", NULL);
	if (!proc_gsc_root)
    		printk(KERN_WARNING
			"pcxl_dma_init: Unable to create gsc /proc dir entry\n");
	else {
		struct proc_dir_entry* ent;
		ent = create_proc_info_entry("pcxl_dma", 0,
				proc_gsc_root, pcxl_proc_info);
		if (!ent)
			printk(KERN_WARNING
				"pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
	}
	return 0;
}

__initcall(pcxl_dma_init);

static void * pa11_dma_alloc_consistent (struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag)
{
	unsigned long vaddr;
	unsigned long paddr;
	int order;

	order = get_order(size);
	size = 1 << (order + PAGE_SHIFT);
	vaddr = pcxl_alloc_range(size);
	paddr = __get_free_pages(flag, order);
	flush_kernel_dcache_range(paddr, size);
	paddr = __pa(paddr);
	map_uncached_pages(vaddr, size, paddr);
	*dma_handle = (dma_addr_t) paddr;

#if 0
/* This probably isn't needed to support EISA cards.
** ISA cards will certainly only support 24-bit DMA addressing.
** Not clear if we can, want, or need to support ISA.
*/
	if (!dev || *dev->coherent_dma_mask < 0xffffffff)
		gfp |= GFP_DMA;
#endif
	return (void *)vaddr;
}

static void pa11_dma_free_consistent (struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle)
{
	int order;

	order = get_order(size);
	size = 1 << (order + PAGE_SHIFT);
	unmap_uncached_pages((unsigned long)vaddr, size);
	pcxl_free_range((unsigned long)vaddr, size);
	free_pages((unsigned long)__va(dma_handle), order);
}

static dma_addr_t pa11_dma_map_single(struct device *dev, void *addr, size_t size, enum dma_data_direction direction)
{
	if (direction == DMA_NONE) {
		printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
		BUG();
	}

	flush_kernel_dcache_range((unsigned long) addr, size);
	return virt_to_phys(addr);
}

static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
{
	if (direction == DMA_NONE) {
		printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
		BUG();
	}

	if (direction == DMA_TO_DEVICE)
	    return;

	/*
	 * For PCI_DMA_FROMDEVICE this flush is not necessary for the
	 * simple map/unmap case. However, it IS necessary if if
	 * pci_dma_sync_single_* has been called and the buffer reused.
	 */

	flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
	return;
}

static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	if (direction == DMA_NONE)
	    BUG();

	for (i = 0; i < nents; i++, sglist++ ) {
		unsigned long vaddr = sg_virt_addr(sglist);
		sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
		sg_dma_len(sglist) = sglist->length;
		flush_kernel_dcache_range(vaddr, sglist->length);
	}
	return nents;
}

static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	if (direction == DMA_NONE)
	    BUG();

	if (direction == DMA_TO_DEVICE)
	    return;

	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */

	for (i = 0; i < nents; i++, sglist++ )
		flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
	return;
}

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)
{
	if (direction == DMA_NONE)
	    BUG();

	flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
}

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)
{
	if (direction == DMA_NONE)
	    BUG();

	flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle) + offset, size);
}

static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */

	for (i = 0; i < nents; i++, sglist++ )
		flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
}

static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
{
	int i;

	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */

	for (i = 0; i < nents; i++, sglist++ )
		flush_kernel_dcache_range(sg_virt_addr(sglist), sglist->length);
}

struct hppa_dma_ops pcxl_dma_ops = {
	.dma_supported =	pa11_dma_supported,
	.alloc_consistent =	pa11_dma_alloc_consistent,
	.alloc_noncoherent =	pa11_dma_alloc_consistent,
	.free_consistent =	pa11_dma_free_consistent,
	.map_single =		pa11_dma_map_single,
	.unmap_single =		pa11_dma_unmap_single,
	.map_sg =		pa11_dma_map_sg,
	.unmap_sg =		pa11_dma_unmap_sg,
	.dma_sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
	.dma_sync_single_for_device = pa11_dma_sync_single_for_device,
	.dma_sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
	.dma_sync_sg_for_device = pa11_dma_sync_sg_for_device,
};

static void *fail_alloc_consistent(struct device *dev, size_t size,
				   dma_addr_t *dma_handle, gfp_t flag)
{
	return NULL;
}

static void *pa11_dma_alloc_noncoherent(struct device *dev, size_t size,
					  dma_addr_t *dma_handle, gfp_t flag)
{
	void *addr = NULL;

	/* rely on kmalloc to be cacheline aligned */
	addr = kmalloc(size, flag);
	if(addr)
		*dma_handle = (dma_addr_t)virt_to_phys(addr);

	return addr;
}

static void pa11_dma_free_noncoherent(struct device *dev, size_t size,
					void *vaddr, dma_addr_t iova)
{
	kfree(vaddr);
	return;
}

struct hppa_dma_ops pcx_dma_ops = {
	.dma_supported =	pa11_dma_supported,
	.alloc_consistent =	fail_alloc_consistent,
	.alloc_noncoherent =	pa11_dma_alloc_noncoherent,
	.free_consistent =	pa11_dma_free_noncoherent,
	.map_single =		pa11_dma_map_single,
	.unmap_single =		pa11_dma_unmap_single,
	.map_sg =		pa11_dma_map_sg,
	.unmap_sg =		pa11_dma_unmap_sg,
	.dma_sync_single_for_cpu =	pa11_dma_sync_single_for_cpu,
	.dma_sync_single_for_device =	pa11_dma_sync_single_for_device,
	.dma_sync_sg_for_cpu =		pa11_dma_sync_sg_for_cpu,
	.dma_sync_sg_for_device =	pa11_dma_sync_sg_for_device,
};


static int pcxl_proc_info(char *buf, char **start, off_t offset, int len)
{
#if 0
	u_long i = 0;
	unsigned long *res_ptr = (u_long *)pcxl_res_map;
#endif
	unsigned long total_pages = pcxl_res_size << 3;   /* 8 bits per byte */

	sprintf(buf, "\nDMA Mapping Area size    : %d bytes (%ld pages)\n",
		PCXL_DMA_MAP_SIZE, total_pages);
	
	sprintf(buf, "%sResource bitmap : %d bytes\n", buf, pcxl_res_size);

	strcat(buf,  "     	  total:    free:    used:   % used:\n");
	sprintf(buf, "%sblocks  %8d %8ld %8ld %8ld%%\n", buf, pcxl_res_size,
		pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
		(pcxl_used_bytes * 100) / pcxl_res_size);

	sprintf(buf, "%spages   %8ld %8ld %8ld %8ld%%\n", buf, total_pages,
		total_pages - pcxl_used_pages, pcxl_used_pages,
		(pcxl_used_pages * 100 / total_pages));

#if 0
	strcat(buf, "\nResource bitmap:");

	for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
		if ((i & 7) == 0)
		    strcat(buf,"\n   ");
		sprintf(buf, "%s %08lx", buf, *res_ptr);
	}
#endif
	strcat(buf, "\n");
	return strlen(buf);
}

OpenPOWER on IntegriCloud