1 // SPDX-License-Identifier: GPL-2.0
3 * Mips Jazz DMA controller support
4 * Copyright (C) 1995, 1996 by Andreas Busse
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.
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/export.h>
14 #include <linux/errno.h>
16 #include <linux/bootmem.h>
17 #include <linux/spinlock.h>
18 #include <linux/gfp.h>
19 #include <linux/dma-direct.h>
20 #include <linux/dma-noncoherent.h>
21 #include <asm/mipsregs.h>
24 #include <linux/uaccess.h>
26 #include <asm/jazzdma.h>
27 #include <asm/pgtable.h>
30 * Set this to one to enable additional vdma debug code.
32 #define CONF_DEBUG_VDMA 0
34 static VDMA_PGTBL_ENTRY *pgtbl;
36 static DEFINE_SPINLOCK(vdma_lock);
41 #define vdma_debug ((CONF_DEBUG_VDMA) ? debuglvl : 0)
43 static int debuglvl = 3;
46 * Initialize the pagetable with a one-to-one mapping of
47 * the first 16 Mbytes of main memory and declare all
48 * entries to be unused. Using this method will at least
49 * allow some early device driver operations to work.
51 static inline void vdma_pgtbl_init(void)
53 unsigned long paddr = 0;
56 for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
57 pgtbl[i].frame = paddr;
58 pgtbl[i].owner = VDMA_PAGE_EMPTY;
59 paddr += VDMA_PAGESIZE;
64 * Initialize the Jazz R4030 dma controller
66 static int __init vdma_init(void)
69 * Allocate 32k of memory for DMA page tables. This needs to be page
70 * aligned and should be uncached to avoid cache flushing after every
73 pgtbl = (VDMA_PGTBL_ENTRY *)__get_free_pages(GFP_KERNEL | GFP_DMA,
74 get_order(VDMA_PGTBL_SIZE));
76 dma_cache_wback_inv((unsigned long)pgtbl, VDMA_PGTBL_SIZE);
77 pgtbl = (VDMA_PGTBL_ENTRY *)CKSEG1ADDR((unsigned long)pgtbl);
80 * Clear the R4030 translation table
84 r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE,
85 CPHYSADDR((unsigned long)pgtbl));
86 r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE);
87 r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
89 printk(KERN_INFO "VDMA: R4030 DMA pagetables initialized.\n");
92 arch_initcall(vdma_init);
95 * Allocate DMA pagetables using a simple first-fit algorithm
97 unsigned long vdma_alloc(unsigned long paddr, unsigned long size)
99 int first, last, pages, frame, i;
100 unsigned long laddr, flags;
102 /* check arguments */
104 if (paddr > 0x1fffffff) {
106 printk("vdma_alloc: Invalid physical address: %08lx\n",
108 return VDMA_ERROR; /* invalid physical address */
110 if (size > 0x400000 || size == 0) {
112 printk("vdma_alloc: Invalid size: %08lx\n", size);
113 return VDMA_ERROR; /* invalid physical address */
116 spin_lock_irqsave(&vdma_lock, flags);
120 pages = VDMA_PAGE(paddr + size) - VDMA_PAGE(paddr) + 1;
123 while (pgtbl[first].owner != VDMA_PAGE_EMPTY &&
124 first < VDMA_PGTBL_ENTRIES) first++;
125 if (first + pages > VDMA_PGTBL_ENTRIES) { /* nothing free */
126 spin_unlock_irqrestore(&vdma_lock, flags);
131 while (pgtbl[last].owner == VDMA_PAGE_EMPTY
132 && last - first < pages)
135 if (last - first == pages)
141 * Mark pages as allocated
143 laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1));
144 frame = paddr & ~(VDMA_PAGESIZE - 1);
146 for (i = first; i < last; i++) {
147 pgtbl[i].frame = frame;
148 pgtbl[i].owner = laddr;
149 frame += VDMA_PAGESIZE;
153 * Update translation table and return logical start address
155 r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
158 printk("vdma_alloc: Allocated %d pages starting from %08lx\n",
161 if (vdma_debug > 2) {
163 for (i = first; i < last; i++)
164 printk("%08x ", i << 12);
166 for (i = first; i < last; i++)
167 printk("%08x ", pgtbl[i].frame);
169 for (i = first; i < last; i++)
170 printk("%08x ", pgtbl[i].owner);
174 spin_unlock_irqrestore(&vdma_lock, flags);
179 EXPORT_SYMBOL(vdma_alloc);
182 * Free previously allocated dma translation pages
183 * Note that this does NOT change the translation table,
184 * it just marks the free'd pages as unused!
186 int vdma_free(unsigned long laddr)
192 if (pgtbl[i].owner != laddr) {
194 ("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
199 while (i < VDMA_PGTBL_ENTRIES && pgtbl[i].owner == laddr) {
200 pgtbl[i].owner = VDMA_PAGE_EMPTY;
205 printk("vdma_free: freed %ld pages starting from %08lx\n",
206 i - (laddr >> 12), laddr);
211 EXPORT_SYMBOL(vdma_free);
214 * Map certain page(s) to another physical address.
215 * Caller must have allocated the page(s) before.
217 int vdma_remap(unsigned long laddr, unsigned long paddr, unsigned long size)
221 if (laddr > 0xffffff) {
224 ("vdma_map: Invalid logical address: %08lx\n",
226 return -EINVAL; /* invalid logical address */
228 if (paddr > 0x1fffffff) {
231 ("vdma_map: Invalid physical address: %08lx\n",
233 return -EINVAL; /* invalid physical address */
236 pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
239 printk("vdma_remap: first=%x, pages=%x\n", first, pages);
240 if (first + pages > VDMA_PGTBL_ENTRIES) {
242 printk("vdma_alloc: Invalid size: %08lx\n", size);
246 paddr &= ~(VDMA_PAGESIZE - 1);
247 while (pages > 0 && first < VDMA_PGTBL_ENTRIES) {
248 if (pgtbl[first].owner != laddr) {
250 printk("Trying to remap other's pages.\n");
251 return -EPERM; /* not owner */
253 pgtbl[first].frame = paddr;
254 paddr += VDMA_PAGESIZE;
260 * Update translation table
262 r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
264 if (vdma_debug > 2) {
266 pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
269 for (i = first; i < first + pages; i++)
270 printk("%08x ", i << 12);
272 for (i = first; i < first + pages; i++)
273 printk("%08x ", pgtbl[i].frame);
275 for (i = first; i < first + pages; i++)
276 printk("%08x ", pgtbl[i].owner);
284 * Translate a physical address to a logical address.
285 * This will return the logical address of the first
288 unsigned long vdma_phys2log(unsigned long paddr)
293 frame = paddr & ~(VDMA_PAGESIZE - 1);
295 for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
296 if (pgtbl[i].frame == frame)
300 if (i == VDMA_PGTBL_ENTRIES)
303 return (i << 12) + (paddr & (VDMA_PAGESIZE - 1));
306 EXPORT_SYMBOL(vdma_phys2log);
309 * Translate a logical DMA address to a physical address
311 unsigned long vdma_log2phys(unsigned long laddr)
313 return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1));
316 EXPORT_SYMBOL(vdma_log2phys);
319 * Print DMA statistics
321 void vdma_stats(void)
325 printk("vdma_stats: CONFIG: %08x\n",
326 r4030_read_reg32(JAZZ_R4030_CONFIG));
327 printk("R4030 translation table base: %08x\n",
328 r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
329 printk("R4030 translation table limit: %08x\n",
330 r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
331 printk("vdma_stats: INV_ADDR: %08x\n",
332 r4030_read_reg32(JAZZ_R4030_INV_ADDR));
333 printk("vdma_stats: R_FAIL_ADDR: %08x\n",
334 r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
335 printk("vdma_stats: M_FAIL_ADDR: %08x\n",
336 r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
337 printk("vdma_stats: IRQ_SOURCE: %08x\n",
338 r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
339 printk("vdma_stats: I386_ERROR: %08x\n",
340 r4030_read_reg32(JAZZ_R4030_I386_ERROR));
341 printk("vdma_chnl_modes: ");
342 for (i = 0; i < 8; i++)
344 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
347 printk("vdma_chnl_enables: ");
348 for (i = 0; i < 8; i++)
350 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
356 * DMA transfer functions
360 * Enable a DMA channel. Also clear any error conditions.
362 void vdma_enable(int channel)
367 printk("vdma_enable: channel %d\n", channel);
370 * Check error conditions first
372 status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
374 printk("VDMA: Channel %d: Address error!\n", channel);
376 printk("VDMA: Channel %d: Memory error!\n", channel);
379 * Clear all interrupt flags
381 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
382 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
383 (channel << 5)) | R4030_TC_INTR
384 | R4030_MEM_INTR | R4030_ADDR_INTR);
387 * Enable the desired channel
389 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
390 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
395 EXPORT_SYMBOL(vdma_enable);
398 * Disable a DMA channel
400 void vdma_disable(int channel)
404 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
407 printk("vdma_disable: channel %d\n", channel);
408 printk("VDMA: channel %d status: %04x (%s) mode: "
409 "%02x addr: %06x count: %06x\n",
411 ((status & 0x600) ? "ERROR" : "OK"),
412 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
414 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR +
416 (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT +
420 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
421 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
426 * After disabling a DMA channel a remote bus register should be
427 * read to ensure that the current DMA acknowledge cycle is completed.
429 *((volatile unsigned int *) JAZZ_DUMMY_DEVICE);
432 EXPORT_SYMBOL(vdma_disable);
435 * Set DMA mode. This function accepts the mode values used
436 * to set a PC-style DMA controller. For the SCSI and FDC
437 * channels, we also set the default modes each time we're
439 * NOTE: The FAST and BURST dma modes are supported by the
440 * R4030 Rev. 2 and PICA chipsets only. I leave them disabled
443 void vdma_set_mode(int channel, int mode)
446 printk("vdma_set_mode: channel %d, mode 0x%x\n", channel,
450 case JAZZ_SCSI_DMA: /* scsi */
451 r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
452 /* R4030_MODE_FAST | */
453 /* R4030_MODE_BURST | */
455 R4030_MODE_WIDTH_16 |
456 R4030_MODE_ATIME_80);
459 case JAZZ_FLOPPY_DMA: /* floppy */
460 r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
461 /* R4030_MODE_FAST | */
462 /* R4030_MODE_BURST | */
465 R4030_MODE_ATIME_120);
468 case JAZZ_AUDIOL_DMA:
469 case JAZZ_AUDIOR_DMA:
470 printk("VDMA: Audio DMA not supported yet.\n");
475 ("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
481 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
482 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
488 r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
489 r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
496 ("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",
501 EXPORT_SYMBOL(vdma_set_mode);
504 * Set Transfer Address
506 void vdma_set_addr(int channel, long addr)
509 printk("vdma_set_addr: channel %d, addr %lx\n", channel,
512 r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr);
515 EXPORT_SYMBOL(vdma_set_addr);
520 void vdma_set_count(int channel, int count)
523 printk("vdma_set_count: channel %d, count %08x\n", channel,
526 r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count);
529 EXPORT_SYMBOL(vdma_set_count);
534 int vdma_get_residue(int channel)
538 residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5));
541 printk("vdma_get_residual: channel %d: residual=%d\n",
548 * Get DMA channel enable register
550 int vdma_get_enable(int channel)
554 enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
557 printk("vdma_get_enable: channel %d: enable=%d\n", channel,
563 static void *jazz_dma_alloc(struct device *dev, size_t size,
564 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
568 ret = dma_direct_alloc(dev, size, dma_handle, gfp, attrs);
572 *dma_handle = vdma_alloc(virt_to_phys(ret), size);
573 if (*dma_handle == VDMA_ERROR) {
574 dma_direct_free(dev, size, ret, *dma_handle, attrs);
578 if (!(attrs & DMA_ATTR_NON_CONSISTENT)) {
579 dma_cache_wback_inv((unsigned long)ret, size);
580 ret = (void *)UNCAC_ADDR(ret);
585 static void jazz_dma_free(struct device *dev, size_t size, void *vaddr,
586 dma_addr_t dma_handle, unsigned long attrs)
588 vdma_free(dma_handle);
589 if (!(attrs & DMA_ATTR_NON_CONSISTENT))
590 vaddr = (void *)CAC_ADDR((unsigned long)vaddr);
591 return dma_direct_free(dev, size, vaddr, dma_handle, attrs);
594 static dma_addr_t jazz_dma_map_page(struct device *dev, struct page *page,
595 unsigned long offset, size_t size, enum dma_data_direction dir,
598 phys_addr_t phys = page_to_phys(page) + offset;
600 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
601 arch_sync_dma_for_device(dev, phys, size, dir);
602 return vdma_alloc(phys, size);
605 static void jazz_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
606 size_t size, enum dma_data_direction dir, unsigned long attrs)
608 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
609 arch_sync_dma_for_cpu(dev, vdma_log2phys(dma_addr), size, dir);
613 static int jazz_dma_map_sg(struct device *dev, struct scatterlist *sglist,
614 int nents, enum dma_data_direction dir, unsigned long attrs)
617 struct scatterlist *sg;
619 for_each_sg(sglist, sg, nents, i) {
620 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
621 arch_sync_dma_for_device(dev, sg_phys(sg), sg->length,
623 sg->dma_address = vdma_alloc(sg_phys(sg), sg->length);
624 if (sg->dma_address == VDMA_ERROR)
626 sg_dma_len(sg) = sg->length;
632 static void jazz_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
633 int nents, enum dma_data_direction dir, unsigned long attrs)
636 struct scatterlist *sg;
638 for_each_sg(sglist, sg, nents, i) {
639 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
640 arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length,
642 vdma_free(sg->dma_address);
646 static void jazz_dma_sync_single_for_device(struct device *dev,
647 dma_addr_t addr, size_t size, enum dma_data_direction dir)
649 arch_sync_dma_for_device(dev, vdma_log2phys(addr), size, dir);
652 static void jazz_dma_sync_single_for_cpu(struct device *dev,
653 dma_addr_t addr, size_t size, enum dma_data_direction dir)
655 arch_sync_dma_for_cpu(dev, vdma_log2phys(addr), size, dir);
658 static void jazz_dma_sync_sg_for_device(struct device *dev,
659 struct scatterlist *sgl, int nents, enum dma_data_direction dir)
661 struct scatterlist *sg;
664 for_each_sg(sgl, sg, nents, i)
665 arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir);
668 static void jazz_dma_sync_sg_for_cpu(struct device *dev,
669 struct scatterlist *sgl, int nents, enum dma_data_direction dir)
671 struct scatterlist *sg;
674 for_each_sg(sgl, sg, nents, i)
675 arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir);
678 static int jazz_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
680 return dma_addr == VDMA_ERROR;
683 const struct dma_map_ops jazz_dma_ops = {
684 .alloc = jazz_dma_alloc,
685 .free = jazz_dma_free,
686 .mmap = arch_dma_mmap,
687 .map_page = jazz_dma_map_page,
688 .unmap_page = jazz_dma_unmap_page,
689 .map_sg = jazz_dma_map_sg,
690 .unmap_sg = jazz_dma_unmap_sg,
691 .sync_single_for_cpu = jazz_dma_sync_single_for_cpu,
692 .sync_single_for_device = jazz_dma_sync_single_for_device,
693 .sync_sg_for_cpu = jazz_dma_sync_sg_for_cpu,
694 .sync_sg_for_device = jazz_dma_sync_sg_for_device,
695 .dma_supported = dma_direct_supported,
696 .cache_sync = arch_dma_cache_sync,
697 .mapping_error = jazz_dma_mapping_error,
699 EXPORT_SYMBOL(jazz_dma_ops);