// SPDX-License-Identifier: GPL-2.0 /* * Mips Jazz DMA controller support * Copyright (C) 1995, 1996 by Andreas Busse * * NOTE: Some of the argument checking could be removed when * things have settled down. Also, instead of returning 0xffffffff * on failure of vdma_alloc() one could leave page #0 unused * and return the more usual NULL pointer as logical address. */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/export.h> #include <linux/errno.h> #include <linux/mm.h> #include <linux/bootmem.h> #include <linux/spinlock.h> #include <linux/gfp.h> #include <asm/mipsregs.h> #include <asm/jazz.h> #include <asm/io.h> #include <linux/uaccess.h> #include <asm/dma.h> #include <asm/jazzdma.h> #include <asm/pgtable.h> /* * Set this to one to enable additional vdma debug code. */ #define CONF_DEBUG_VDMA 0 static VDMA_PGTBL_ENTRY *pgtbl; static DEFINE_SPINLOCK(vdma_lock); /* * Debug stuff */ #define vdma_debug ((CONF_DEBUG_VDMA) ? debuglvl : 0) static int debuglvl = 3; /* * Initialize the pagetable with a one-to-one mapping of * the first 16 Mbytes of main memory and declare all * entries to be unused. Using this method will at least * allow some early device driver operations to work. */ static inline void vdma_pgtbl_init(void) { unsigned long paddr = 0; int i; for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) { pgtbl[i].frame = paddr; pgtbl[i].owner = VDMA_PAGE_EMPTY; paddr += VDMA_PAGESIZE; } } /* * Initialize the Jazz R4030 dma controller */ static int __init vdma_init(void) { /* * Allocate 32k of memory for DMA page tables. This needs to be page * aligned and should be uncached to avoid cache flushing after every * update. */ pgtbl = (VDMA_PGTBL_ENTRY *)__get_free_pages(GFP_KERNEL | GFP_DMA, get_order(VDMA_PGTBL_SIZE)); BUG_ON(!pgtbl); dma_cache_wback_inv((unsigned long)pgtbl, VDMA_PGTBL_SIZE); pgtbl = (VDMA_PGTBL_ENTRY *)KSEG1ADDR(pgtbl); /* * Clear the R4030 translation table */ vdma_pgtbl_init(); r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE, CPHYSADDR(pgtbl)); r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE); r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0); printk(KERN_INFO "VDMA: R4030 DMA pagetables initialized.\n"); return 0; } /* * Allocate DMA pagetables using a simple first-fit algorithm */ unsigned long vdma_alloc(unsigned long paddr, unsigned long size) { int first, last, pages, frame, i; unsigned long laddr, flags; /* check arguments */ if (paddr > 0x1fffffff) { if (vdma_debug) printk("vdma_alloc: Invalid physical address: %08lx\n", paddr); return VDMA_ERROR; /* invalid physical address */ } if (size > 0x400000 || size == 0) { if (vdma_debug) printk("vdma_alloc: Invalid size: %08lx\n", size); return VDMA_ERROR; /* invalid physical address */ } spin_lock_irqsave(&vdma_lock, flags); /* * Find free chunk */ pages = VDMA_PAGE(paddr + size) - VDMA_PAGE(paddr) + 1; first = 0; while (1) { while (pgtbl[first].owner != VDMA_PAGE_EMPTY && first < VDMA_PGTBL_ENTRIES) first++; if (first + pages > VDMA_PGTBL_ENTRIES) { /* nothing free */ spin_unlock_irqrestore(&vdma_lock, flags); return VDMA_ERROR; } last = first + 1; while (pgtbl[last].owner == VDMA_PAGE_EMPTY && last - first < pages) last++; if (last - first == pages) break; /* found */ first = last + 1; } /* * Mark pages as allocated */ laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1)); frame = paddr & ~(VDMA_PAGESIZE - 1); for (i = first; i < last; i++) { pgtbl[i].frame = frame; pgtbl[i].owner = laddr; frame += VDMA_PAGESIZE; } /* * Update translation table and return logical start address */ r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0); if (vdma_debug > 1) printk("vdma_alloc: Allocated %d pages starting from %08lx\n", pages, laddr); if (vdma_debug > 2) { printk("LADDR: "); for (i = first; i < last; i++) printk("%08x ", i << 12); printk("\nPADDR: "); for (i = first; i < last; i++) printk("%08x ", pgtbl[i].frame); printk("\nOWNER: "); for (i = first; i < last; i++) printk("%08x ", pgtbl[i].owner); printk("\n"); } spin_unlock_irqrestore(&vdma_lock, flags); return laddr; } EXPORT_SYMBOL(vdma_alloc); /* * Free previously allocated dma translation pages * Note that this does NOT change the translation table, * it just marks the free'd pages as unused! */ int vdma_free(unsigned long laddr) { int i; i = laddr >> 12; if (pgtbl[i].owner != laddr) { printk ("vdma_free: trying to free other's dma pages, laddr=%8lx\n", laddr); return -1; } while (i < VDMA_PGTBL_ENTRIES && pgtbl[i].owner == laddr) { pgtbl[i].owner = VDMA_PAGE_EMPTY; i++; } if (vdma_debug > 1) printk("vdma_free: freed %ld pages starting from %08lx\n", i - (laddr >> 12), laddr); return 0; } EXPORT_SYMBOL(vdma_free); /* * Map certain page(s) to another physical address. * Caller must have allocated the page(s) before. */ int vdma_remap(unsigned long laddr, unsigned long paddr, unsigned long size) { int first, pages; if (laddr > 0xffffff) { if (vdma_debug) printk ("vdma_map: Invalid logical address: %08lx\n", laddr); return -EINVAL; /* invalid logical address */ } if (paddr > 0x1fffffff) { if (vdma_debug) printk ("vdma_map: Invalid physical address: %08lx\n", paddr); return -EINVAL; /* invalid physical address */ } pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1; first = laddr >> 12; if (vdma_debug) printk("vdma_remap: first=%x, pages=%x\n", first, pages); if (first + pages > VDMA_PGTBL_ENTRIES) { if (vdma_debug) printk("vdma_alloc: Invalid size: %08lx\n", size); return -EINVAL; } paddr &= ~(VDMA_PAGESIZE - 1); while (pages > 0 && first < VDMA_PGTBL_ENTRIES) { if (pgtbl[first].owner != laddr) { if (vdma_debug) printk("Trying to remap other's pages.\n"); return -EPERM; /* not owner */ } pgtbl[first].frame = paddr; paddr += VDMA_PAGESIZE; first++; pages--; } /* * Update translation table */ r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0); if (vdma_debug > 2) { int i; pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1; first = laddr >> 12; printk("LADDR: "); for (i = first; i < first + pages; i++) printk("%08x ", i << 12); printk("\nPADDR: "); for (i = first; i < first + pages; i++) printk("%08x ", pgtbl[i].frame); printk("\nOWNER: "); for (i = first; i < first + pages; i++) printk("%08x ", pgtbl[i].owner); printk("\n"); } return 0; } /* * Translate a physical address to a logical address. * This will return the logical address of the first * match. */ unsigned long vdma_phys2log(unsigned long paddr) { int i; int frame; frame = paddr & ~(VDMA_PAGESIZE - 1); for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) { if (pgtbl[i].frame == frame) break; } if (i == VDMA_PGTBL_ENTRIES) return ~0UL; return (i << 12) + (paddr & (VDMA_PAGESIZE - 1)); } EXPORT_SYMBOL(vdma_phys2log); /* * Translate a logical DMA address to a physical address */ unsigned long vdma_log2phys(unsigned long laddr) { return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1)); } EXPORT_SYMBOL(vdma_log2phys); /* * Print DMA statistics */ void vdma_stats(void) { int i; printk("vdma_stats: CONFIG: %08x\n", r4030_read_reg32(JAZZ_R4030_CONFIG)); printk("R4030 translation table base: %08x\n", r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE)); printk("R4030 translation table limit: %08x\n", r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM)); printk("vdma_stats: INV_ADDR: %08x\n", r4030_read_reg32(JAZZ_R4030_INV_ADDR)); printk("vdma_stats: R_FAIL_ADDR: %08x\n", r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR)); printk("vdma_stats: M_FAIL_ADDR: %08x\n", r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR)); printk("vdma_stats: IRQ_SOURCE: %08x\n", r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE)); printk("vdma_stats: I386_ERROR: %08x\n", r4030_read_reg32(JAZZ_R4030_I386_ERROR)); printk("vdma_chnl_modes: "); for (i = 0; i < 8; i++) printk("%04x ", (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE + (i << 5))); printk("\n"); printk("vdma_chnl_enables: "); for (i = 0; i < 8; i++) printk("%04x ", (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (i << 5))); printk("\n"); } /* * DMA transfer functions */ /* * Enable a DMA channel. Also clear any error conditions. */ void vdma_enable(int channel) { int status; if (vdma_debug) printk("vdma_enable: channel %d\n", channel); /* * Check error conditions first */ status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)); if (status & 0x400) printk("VDMA: Channel %d: Address error!\n", channel); if (status & 0x200) printk("VDMA: Channel %d: Memory error!\n", channel); /* * Clear all interrupt flags */ r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5), r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)) | R4030_TC_INTR | R4030_MEM_INTR | R4030_ADDR_INTR); /* * Enable the desired channel */ r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5), r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)) | R4030_CHNL_ENABLE); } EXPORT_SYMBOL(vdma_enable); /* * Disable a DMA channel */ void vdma_disable(int channel) { if (vdma_debug) { int status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)); printk("vdma_disable: channel %d\n", channel); printk("VDMA: channel %d status: %04x (%s) mode: " "%02x addr: %06x count: %06x\n", channel, status, ((status & 0x600) ? "ERROR" : "OK"), (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5)), (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5)), (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5))); } r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5), r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)) & ~R4030_CHNL_ENABLE); /* * After disabling a DMA channel a remote bus register should be * read to ensure that the current DMA acknowledge cycle is completed. */ *((volatile unsigned int *) JAZZ_DUMMY_DEVICE); } EXPORT_SYMBOL(vdma_disable); /* * Set DMA mode. This function accepts the mode values used * to set a PC-style DMA controller. For the SCSI and FDC * channels, we also set the default modes each time we're * called. * NOTE: The FAST and BURST dma modes are supported by the * R4030 Rev. 2 and PICA chipsets only. I leave them disabled * for now. */ void vdma_set_mode(int channel, int mode) { if (vdma_debug) printk("vdma_set_mode: channel %d, mode 0x%x\n", channel, mode); switch (channel) { case JAZZ_SCSI_DMA: /* scsi */ r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5), /* R4030_MODE_FAST | */ /* R4030_MODE_BURST | */ R4030_MODE_INTR_EN | R4030_MODE_WIDTH_16 | R4030_MODE_ATIME_80); break; case JAZZ_FLOPPY_DMA: /* floppy */ r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5), /* R4030_MODE_FAST | */ /* R4030_MODE_BURST | */ R4030_MODE_INTR_EN | R4030_MODE_WIDTH_8 | R4030_MODE_ATIME_120); break; case JAZZ_AUDIOL_DMA: case JAZZ_AUDIOR_DMA: printk("VDMA: Audio DMA not supported yet.\n"); break; default: printk ("VDMA: vdma_set_mode() called with unsupported channel %d!\n", channel); } switch (mode) { case DMA_MODE_READ: r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5), r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)) & ~R4030_CHNL_WRITE); break; case DMA_MODE_WRITE: r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5), r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)) | R4030_CHNL_WRITE); break; default: printk ("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n", mode); } } EXPORT_SYMBOL(vdma_set_mode); /* * Set Transfer Address */ void vdma_set_addr(int channel, long addr) { if (vdma_debug) printk("vdma_set_addr: channel %d, addr %lx\n", channel, addr); r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr); } EXPORT_SYMBOL(vdma_set_addr); /* * Set Transfer Count */ void vdma_set_count(int channel, int count) { if (vdma_debug) printk("vdma_set_count: channel %d, count %08x\n", channel, (unsigned) count); r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count); } EXPORT_SYMBOL(vdma_set_count); /* * Get Residual */ int vdma_get_residue(int channel) { int residual; residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5)); if (vdma_debug) printk("vdma_get_residual: channel %d: residual=%d\n", channel, residual); return residual; } /* * Get DMA channel enable register */ int vdma_get_enable(int channel) { int enable; enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5)); if (vdma_debug) printk("vdma_get_enable: channel %d: enable=%d\n", channel, enable); return enable; } arch_initcall(vdma_init);