1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Mips Jazz DMA controller support
4 * Copyright (C) 1995, 1996 by Andreas Busse
5 *
6 * NOTE: Some of the argument checking could be removed when
7 * things have settled down. Also, instead of returning 0xffffffff
8 * on failure of vdma_alloc() one could leave page #0 unused
9 * and return the more usual NULL pointer as logical address.
10 */
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/export.h>
14 #include <linux/errno.h>
15 #include <linux/mm.h>
16 #include <linux/memblock.h>
17 #include <linux/spinlock.h>
18 #include <linux/gfp.h>
19 #include <linux/dma-map-ops.h>
20 #include <asm/mipsregs.h>
21 #include <asm/jazz.h>
22 #include <asm/io.h>
23 #include <linux/uaccess.h>
24 #include <asm/dma.h>
25 #include <asm/jazzdma.h>
26
27 /*
28 * Set this to one to enable additional vdma debug code.
29 */
30 #define CONF_DEBUG_VDMA 0
31
32 static VDMA_PGTBL_ENTRY *pgtbl;
33
34 static DEFINE_SPINLOCK(vdma_lock);
35
36 /*
37 * Debug stuff
38 */
39 #define vdma_debug ((CONF_DEBUG_VDMA) ? debuglvl : 0)
40
41 static int debuglvl = 3;
42
43 /*
44 * Initialize the pagetable with a one-to-one mapping of
45 * the first 16 Mbytes of main memory and declare all
46 * entries to be unused. Using this method will at least
47 * allow some early device driver operations to work.
48 */
49 static inline void vdma_pgtbl_init(void)
50 {
51 unsigned long paddr = 0;
52 int i;
53
54 for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
55 pgtbl[i].frame = paddr;
56 pgtbl[i].owner = VDMA_PAGE_EMPTY;
57 paddr += VDMA_PAGESIZE;
58 }
59 }
60
61 /*
62 * Initialize the Jazz R4030 dma controller
63 */
64 static int __init vdma_init(void)
65 {
66 /*
67 * Allocate 32k of memory for DMA page tables. This needs to be page
68 * aligned and should be uncached to avoid cache flushing after every
69 * update.
70 */
71 pgtbl = (VDMA_PGTBL_ENTRY *)__get_free_pages(GFP_KERNEL | GFP_DMA,
72 get_order(VDMA_PGTBL_SIZE));
73 BUG_ON(!pgtbl);
74 dma_cache_wback_inv((unsigned long)pgtbl, VDMA_PGTBL_SIZE);
75 pgtbl = (VDMA_PGTBL_ENTRY *)CKSEG1ADDR((unsigned long)pgtbl);
76
77 /*
78 * Clear the R4030 translation table
79 */
80 vdma_pgtbl_init();
81
82 r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE,
83 CPHYSADDR((unsigned long)pgtbl));
84 r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE);
85 r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
86
87 printk(KERN_INFO "VDMA: R4030 DMA pagetables initialized.\n");
88 return 0;
89 }
90 arch_initcall(vdma_init);
91
92 /*
93 * Allocate DMA pagetables using a simple first-fit algorithm
94 */
95 unsigned long vdma_alloc(unsigned long paddr, unsigned long size)
96 {
97 int first, last, pages, frame, i;
98 unsigned long laddr, flags;
99
100 /* check arguments */
101
102 if (paddr > 0x1fffffff) {
103 if (vdma_debug)
104 printk("vdma_alloc: Invalid physical address: %08lx\n",
105 paddr);
106 return DMA_MAPPING_ERROR; /* invalid physical address */
107 }
108 if (size > 0x400000 || size == 0) {
109 if (vdma_debug)
110 printk("vdma_alloc: Invalid size: %08lx\n", size);
111 return DMA_MAPPING_ERROR; /* invalid physical address */
112 }
113
114 spin_lock_irqsave(&vdma_lock, flags);
115 /*
116 * Find free chunk
117 */
118 pages = VDMA_PAGE(paddr + size) - VDMA_PAGE(paddr) + 1;
119 first = 0;
120 while (1) {
121 while (pgtbl[first].owner != VDMA_PAGE_EMPTY &&
122 first < VDMA_PGTBL_ENTRIES) first++;
123 if (first + pages > VDMA_PGTBL_ENTRIES) { /* nothing free */
124 spin_unlock_irqrestore(&vdma_lock, flags);
125 return DMA_MAPPING_ERROR;
126 }
127
128 last = first + 1;
129 while (pgtbl[last].owner == VDMA_PAGE_EMPTY
130 && last - first < pages)
131 last++;
132
133 if (last - first == pages)
134 break; /* found */
135 first = last + 1;
136 }
137
138 /*
139 * Mark pages as allocated
140 */
141 laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1));
142 frame = paddr & ~(VDMA_PAGESIZE - 1);
143
144 for (i = first; i < last; i++) {
145 pgtbl[i].frame = frame;
146 pgtbl[i].owner = laddr;
147 frame += VDMA_PAGESIZE;
148 }
149
150 /*
151 * Update translation table and return logical start address
152 */
153 r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
154
155 if (vdma_debug > 1)
156 printk("vdma_alloc: Allocated %d pages starting from %08lx\n",
157 pages, laddr);
158
159 if (vdma_debug > 2) {
160 printk("LADDR: ");
161 for (i = first; i < last; i++)
162 printk("%08x ", i << 12);
163 printk("\nPADDR: ");
164 for (i = first; i < last; i++)
165 printk("%08x ", pgtbl[i].frame);
166 printk("\nOWNER: ");
167 for (i = first; i < last; i++)
168 printk("%08x ", pgtbl[i].owner);
169 printk("\n");
170 }
171
172 spin_unlock_irqrestore(&vdma_lock, flags);
173
174 return laddr;
175 }
176
177 EXPORT_SYMBOL(vdma_alloc);
178
179 /*
180 * Free previously allocated dma translation pages
181 * Note that this does NOT change the translation table,
182 * it just marks the free'd pages as unused!
183 */
184 int vdma_free(unsigned long laddr)
185 {
186 int i;
187
188 i = laddr >> 12;
189
190 if (pgtbl[i].owner != laddr) {
191 printk
192 ("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
193 laddr);
194 return -1;
195 }
196
197 while (i < VDMA_PGTBL_ENTRIES && pgtbl[i].owner == laddr) {
198 pgtbl[i].owner = VDMA_PAGE_EMPTY;
199 i++;
200 }
201
202 if (vdma_debug > 1)
203 printk("vdma_free: freed %ld pages starting from %08lx\n",
204 i - (laddr >> 12), laddr);
205
206 return 0;
207 }
208
209 EXPORT_SYMBOL(vdma_free);
210
211 /*
212 * Translate a physical address to a logical address.
213 * This will return the logical address of the first
214 * match.
215 */
216 unsigned long vdma_phys2log(unsigned long paddr)
217 {
218 int i;
219 int frame;
220
221 frame = paddr & ~(VDMA_PAGESIZE - 1);
222
223 for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
224 if (pgtbl[i].frame == frame)
225 break;
226 }
227
228 if (i == VDMA_PGTBL_ENTRIES)
229 return ~0UL;
230
231 return (i << 12) + (paddr & (VDMA_PAGESIZE - 1));
232 }
233
234 EXPORT_SYMBOL(vdma_phys2log);
235
236 /*
237 * Translate a logical DMA address to a physical address
238 */
239 unsigned long vdma_log2phys(unsigned long laddr)
240 {
241 return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1));
242 }
243
244 EXPORT_SYMBOL(vdma_log2phys);
245
246 /*
247 * Print DMA statistics
248 */
249 void vdma_stats(void)
250 {
251 int i;
252
253 printk("vdma_stats: CONFIG: %08x\n",
254 r4030_read_reg32(JAZZ_R4030_CONFIG));
255 printk("R4030 translation table base: %08x\n",
256 r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
257 printk("R4030 translation table limit: %08x\n",
258 r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
259 printk("vdma_stats: INV_ADDR: %08x\n",
260 r4030_read_reg32(JAZZ_R4030_INV_ADDR));
261 printk("vdma_stats: R_FAIL_ADDR: %08x\n",
262 r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
263 printk("vdma_stats: M_FAIL_ADDR: %08x\n",
264 r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
265 printk("vdma_stats: IRQ_SOURCE: %08x\n",
266 r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
267 printk("vdma_stats: I386_ERROR: %08x\n",
268 r4030_read_reg32(JAZZ_R4030_I386_ERROR));
269 printk("vdma_chnl_modes: ");
270 for (i = 0; i < 8; i++)
271 printk("%04x ",
272 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
273 (i << 5)));
274 printk("\n");
275 printk("vdma_chnl_enables: ");
276 for (i = 0; i < 8; i++)
277 printk("%04x ",
278 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
279 (i << 5)));
280 printk("\n");
281 }
282
283 /*
284 * DMA transfer functions
285 */
286
287 /*
288 * Enable a DMA channel. Also clear any error conditions.
289 */
290 void vdma_enable(int channel)
291 {
292 int status;
293
294 if (vdma_debug)
295 printk("vdma_enable: channel %d\n", channel);
296
297 /*
298 * Check error conditions first
299 */
300 status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
301 if (status & 0x400)
302 printk("VDMA: Channel %d: Address error!\n", channel);
303 if (status & 0x200)
304 printk("VDMA: Channel %d: Memory error!\n", channel);
305
306 /*
307 * Clear all interrupt flags
308 */
309 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
310 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
311 (channel << 5)) | R4030_TC_INTR
312 | R4030_MEM_INTR | R4030_ADDR_INTR);
313
314 /*
315 * Enable the desired channel
316 */
317 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
318 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
319 (channel << 5)) |
320 R4030_CHNL_ENABLE);
321 }
322
323 EXPORT_SYMBOL(vdma_enable);
324
325 /*
326 * Disable a DMA channel
327 */
328 void vdma_disable(int channel)
329 {
330 if (vdma_debug) {
331 int status =
332 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
333 (channel << 5));
334
335 printk("vdma_disable: channel %d\n", channel);
336 printk("VDMA: channel %d status: %04x (%s) mode: "
337 "%02x addr: %06x count: %06x\n",
338 channel, status,
339 ((status & 0x600) ? "ERROR" : "OK"),
340 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
341 (channel << 5)),
342 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR +
343 (channel << 5)),
344 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT +
345 (channel << 5)));
346 }
347
348 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
349 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
350 (channel << 5)) &
351 ~R4030_CHNL_ENABLE);
352
353 /*
354 * After disabling a DMA channel a remote bus register should be
355 * read to ensure that the current DMA acknowledge cycle is completed.
356 */
357 *((volatile unsigned int *) JAZZ_DUMMY_DEVICE);
358 }
359
360 EXPORT_SYMBOL(vdma_disable);
361
362 /*
363 * Set DMA mode. This function accepts the mode values used
364 * to set a PC-style DMA controller. For the SCSI and FDC
365 * channels, we also set the default modes each time we're
366 * called.
367 * NOTE: The FAST and BURST dma modes are supported by the
368 * R4030 Rev. 2 and PICA chipsets only. I leave them disabled
369 * for now.
370 */
371 void vdma_set_mode(int channel, int mode)
372 {
373 if (vdma_debug)
374 printk("vdma_set_mode: channel %d, mode 0x%x\n", channel,
375 mode);
376
377 switch (channel) {
378 case JAZZ_SCSI_DMA: /* scsi */
379 r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
380 /* R4030_MODE_FAST | */
381 /* R4030_MODE_BURST | */
382 R4030_MODE_INTR_EN |
383 R4030_MODE_WIDTH_16 |
384 R4030_MODE_ATIME_80);
385 break;
386
387 case JAZZ_FLOPPY_DMA: /* floppy */
388 r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
389 /* R4030_MODE_FAST | */
390 /* R4030_MODE_BURST | */
391 R4030_MODE_INTR_EN |
392 R4030_MODE_WIDTH_8 |
393 R4030_MODE_ATIME_120);
394 break;
395
396 case JAZZ_AUDIOL_DMA:
397 case JAZZ_AUDIOR_DMA:
398 printk("VDMA: Audio DMA not supported yet.\n");
399 break;
400
401 default:
402 printk
403 ("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
404 channel);
405 }
406
407 switch (mode) {
408 case DMA_MODE_READ:
409 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
410 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
411 (channel << 5)) &
412 ~R4030_CHNL_WRITE);
413 break;
414
415 case DMA_MODE_WRITE:
416 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
417 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
418 (channel << 5)) |
419 R4030_CHNL_WRITE);
420 break;
421
422 default:
423 printk
424 ("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",
425 mode);
426 }
427 }
428
429 EXPORT_SYMBOL(vdma_set_mode);
430
431 /*
432 * Set Transfer Address
433 */
434 void vdma_set_addr(int channel, long addr)
435 {
436 if (vdma_debug)
437 printk("vdma_set_addr: channel %d, addr %lx\n", channel,
438 addr);
439
440 r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr);
441 }
442
443 EXPORT_SYMBOL(vdma_set_addr);
444
445 /*
446 * Set Transfer Count
447 */
448 void vdma_set_count(int channel, int count)
449 {
450 if (vdma_debug)
451 printk("vdma_set_count: channel %d, count %08x\n", channel,
452 (unsigned) count);
453
454 r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count);
455 }
456
457 EXPORT_SYMBOL(vdma_set_count);
458
459 /*
460 * Get Residual
461 */
462 int vdma_get_residue(int channel)
463 {
464 int residual;
465
466 residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5));
467
468 if (vdma_debug)
469 printk("vdma_get_residual: channel %d: residual=%d\n",
470 channel, residual);
471
472 return residual;
473 }
474
475 /*
476 * Get DMA channel enable register
477 */
478 int vdma_get_enable(int channel)
479 {
480 int enable;
481
482 enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
483
484 if (vdma_debug)
485 printk("vdma_get_enable: channel %d: enable=%d\n", channel,
486 enable);
487
488 return enable;
489 }
490
491 static void *jazz_dma_alloc(struct device *dev, size_t size,
492 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
493 {
494 struct page *page;
495 void *ret;
496
497 if (attrs & DMA_ATTR_NO_WARN)
498 gfp |= __GFP_NOWARN;
499
500 size = PAGE_ALIGN(size);
501 page = alloc_pages(gfp, get_order(size));
502 if (!page)
503 return NULL;
504 ret = page_address(page);
505 memset(ret, 0, size);
506 *dma_handle = vdma_alloc(virt_to_phys(ret), size);
507 if (*dma_handle == DMA_MAPPING_ERROR)
508 goto out_free_pages;
509 arch_dma_prep_coherent(page, size);
510 return (void *)(UNCAC_BASE + __pa(ret));
511
512 out_free_pages:
513 __free_pages(page, get_order(size));
514 return NULL;
515 }
516
517 static void jazz_dma_free(struct device *dev, size_t size, void *vaddr,
518 dma_addr_t dma_handle, unsigned long attrs)
519 {
520 vdma_free(dma_handle);
521 __free_pages(virt_to_page(vaddr), get_order(size));
522 }
523
524 static dma_addr_t jazz_dma_map_page(struct device *dev, struct page *page,
525 unsigned long offset, size_t size, enum dma_data_direction dir,
526 unsigned long attrs)
527 {
528 phys_addr_t phys = page_to_phys(page) + offset;
529
530 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
531 arch_sync_dma_for_device(phys, size, dir);
532 return vdma_alloc(phys, size);
533 }
534
535 static void jazz_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
536 size_t size, enum dma_data_direction dir, unsigned long attrs)
537 {
538 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
539 arch_sync_dma_for_cpu(vdma_log2phys(dma_addr), size, dir);
540 vdma_free(dma_addr);
541 }
542
543 static int jazz_dma_map_sg(struct device *dev, struct scatterlist *sglist,
544 int nents, enum dma_data_direction dir, unsigned long attrs)
545 {
546 int i;
547 struct scatterlist *sg;
548
549 for_each_sg(sglist, sg, nents, i) {
550 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
551 arch_sync_dma_for_device(sg_phys(sg), sg->length,
552 dir);
553 sg->dma_address = vdma_alloc(sg_phys(sg), sg->length);
554 if (sg->dma_address == DMA_MAPPING_ERROR)
555 return -EIO;
556 sg_dma_len(sg) = sg->length;
557 }
558
559 return nents;
560 }
561
562 static void jazz_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
563 int nents, enum dma_data_direction dir, unsigned long attrs)
564 {
565 int i;
566 struct scatterlist *sg;
567
568 for_each_sg(sglist, sg, nents, i) {
569 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
570 arch_sync_dma_for_cpu(sg_phys(sg), sg->length, dir);
571 vdma_free(sg->dma_address);
572 }
573 }
574
575 static void jazz_dma_sync_single_for_device(struct device *dev,
576 dma_addr_t addr, size_t size, enum dma_data_direction dir)
577 {
578 arch_sync_dma_for_device(vdma_log2phys(addr), size, dir);
579 }
580
581 static void jazz_dma_sync_single_for_cpu(struct device *dev,
582 dma_addr_t addr, size_t size, enum dma_data_direction dir)
583 {
584 arch_sync_dma_for_cpu(vdma_log2phys(addr), size, dir);
585 }
586
587 static void jazz_dma_sync_sg_for_device(struct device *dev,
588 struct scatterlist *sgl, int nents, enum dma_data_direction dir)
589 {
590 struct scatterlist *sg;
591 int i;
592
593 for_each_sg(sgl, sg, nents, i)
594 arch_sync_dma_for_device(sg_phys(sg), sg->length, dir);
595 }
596
597 static void jazz_dma_sync_sg_for_cpu(struct device *dev,
598 struct scatterlist *sgl, int nents, enum dma_data_direction dir)
599 {
600 struct scatterlist *sg;
601 int i;
602
603 for_each_sg(sgl, sg, nents, i)
604 arch_sync_dma_for_cpu(sg_phys(sg), sg->length, dir);
605 }
606
607 const struct dma_map_ops jazz_dma_ops = {
608 .alloc = jazz_dma_alloc,
609 .free = jazz_dma_free,
610 .map_page = jazz_dma_map_page,
611 .unmap_page = jazz_dma_unmap_page,
612 .map_sg = jazz_dma_map_sg,
613 .unmap_sg = jazz_dma_unmap_sg,
614 .sync_single_for_cpu = jazz_dma_sync_single_for_cpu,
615 .sync_single_for_device = jazz_dma_sync_single_for_device,
616 .sync_sg_for_cpu = jazz_dma_sync_sg_for_cpu,
617 .sync_sg_for_device = jazz_dma_sync_sg_for_device,
618 .mmap = dma_common_mmap,
619 .get_sgtable = dma_common_get_sgtable,
620 .alloc_pages_op = dma_common_alloc_pages,
621 .free_pages = dma_common_free_pages,
622 };
623 EXPORT_SYMBOL(jazz_dma_ops);
624
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