/*- * Copyright (c) 1991 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * William Jolitz. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)isa.c 7.2 (Berkeley) 5/13/91 * $FreeBSD: src/sys/i386/isa/isa_dma.c,v 1.4.2.1 2000/08/08 19:49:53 peter Exp $ */ /* * code to manage AT bus * * 92/08/18 Frank P. MacLachlan (fpm@crash.cts.com): * Fixed uninitialized variable problem and added code to deal * with DMA page boundaries in isa_dmarangecheck(). Fixed word * mode DMA count compution and reorganized DMA setup code in * isa_dmastart() */ #include #include #include #include #include #include #include #include #include #include "isa.h" #include #include #include /* ** Register definitions for DMA controller 1 (channels 0..3): */ #define DMA1_CHN(c) (IO_DMA1 + 1*(2*(c))) /* addr reg for channel c */ #define DMA1_SMSK (IO_DMA1 + 1*10) /* single mask register */ #define DMA1_MODE (IO_DMA1 + 1*11) /* mode register */ #define DMA1_FFC (IO_DMA1 + 1*12) /* clear first/last FF */ /* ** Register definitions for DMA controller 2 (channels 4..7): */ #define DMA2_CHN(c) (IO_DMA2 + 2*(2*(c))) /* addr reg for channel c */ #define DMA2_SMSK (IO_DMA2 + 2*10) /* single mask register */ #define DMA2_MODE (IO_DMA2 + 2*11) /* mode register */ #define DMA2_FFC (IO_DMA2 + 2*12) /* clear first/last FF */ static int isa_dmarangecheck (caddr_t va, u_int length, int chan); static caddr_t dma_bouncebuf[8]; static u_int dma_bouncebufsize[8]; static u_int8_t dma_bounced = 0; static u_int8_t dma_busy = 0; /* Used in isa_dmastart() */ static u_int8_t dma_inuse = 0; /* User for acquire/release */ static u_int8_t dma_auto_mode = 0; #define VALID_DMA_MASK (7) /* high byte of address is stored in this port for i-th dma channel */ static int dmapageport[8] = { 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a }; /* * Setup a DMA channel's bounce buffer. */ void isa_dmainit(int chan, u_int bouncebufsize) { void *buf; #ifdef DIAGNOSTIC if (chan & ~VALID_DMA_MASK) panic("isa_dmainit: channel out of range"); if (dma_bouncebuf[chan] != NULL) panic("isa_dmainit: impossible request"); #endif dma_bouncebufsize[chan] = bouncebufsize; /* Try malloc() first. It works better if it works. */ buf = kmalloc(bouncebufsize, M_DEVBUF, M_NOWAIT); if (buf != NULL) { if (isa_dmarangecheck(buf, bouncebufsize, chan) == 0) { dma_bouncebuf[chan] = buf; return; } kfree(buf, M_DEVBUF); } buf = contigmalloc(bouncebufsize, M_DEVBUF, M_NOWAIT, 0ul, 0xfffffful, 1ul, chan & 4 ? 0x20000ul : 0x10000ul); if (buf == NULL) kprintf("isa_dmainit(%d, %d) failed\n", chan, bouncebufsize); else dma_bouncebuf[chan] = buf; } /* * Register a DMA channel's usage. Usually called from a device driver * in open() or during its initialization. */ int isa_dma_acquire(int chan) { #ifdef DIAGNOSTIC if (chan & ~VALID_DMA_MASK) panic("isa_dma_acquire: channel out of range"); #endif if (dma_inuse & (1 << chan)) { kprintf("isa_dma_acquire: channel %d already in use\n", chan); return (EBUSY); } dma_inuse |= (1 << chan); dma_auto_mode &= ~(1 << chan); return (0); } /* * Unregister a DMA channel's usage. Usually called from a device driver * during close() or during its shutdown. */ void isa_dma_release(int chan) { #ifdef DIAGNOSTIC if (chan & ~VALID_DMA_MASK) panic("isa_dma_release: channel out of range"); if ((dma_inuse & (1 << chan)) == 0) kprintf("isa_dma_release: channel %d not in use\n", chan); #endif if (dma_busy & (1 << chan)) { dma_busy &= ~(1 << chan); /* * XXX We should also do "dma_bounced &= (1 << chan);" * because we are acting on behalf of isa_dmadone() which * was not called to end the last DMA operation. This does * not matter now, but it may in the future. */ } dma_inuse &= ~(1 << chan); dma_auto_mode &= ~(1 << chan); } /* * isa_dmacascade(): program 8237 DMA controller channel to accept * external dma control by a board. */ void isa_dmacascade(int chan) { #ifdef DIAGNOSTIC if (chan & ~VALID_DMA_MASK) panic("isa_dmacascade: channel out of range"); #endif /* set dma channel mode, and set dma channel mode */ if ((chan & 4) == 0) { outb(DMA1_MODE, DMA37MD_CASCADE | chan); outb(DMA1_SMSK, chan); } else { outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3)); outb(DMA2_SMSK, chan & 3); } } /* * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment * problems by using a bounce buffer. */ void isa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan) { vm_paddr_t phys; int waport; caddr_t newaddr; #ifdef DIAGNOSTIC if (chan & ~VALID_DMA_MASK) panic("isa_dmastart: channel out of range"); if ((chan < 4 && nbytes > (1<<16)) || (chan >= 4 && (nbytes > (1<<17) || (u_int)(uintptr_t)addr & 1))) panic("isa_dmastart: impossible request"); if ((dma_inuse & (1 << chan)) == 0) kprintf("isa_dmastart: channel %d not acquired\n", chan); #endif #if 0 /* * XXX This should be checked, but drivers like ad1848 only call * isa_dmastart() once because they use Auto DMA mode. If we * leave this in, drivers that do this will print this continuously. */ if (dma_busy & (1 << chan)) kprintf("isa_dmastart: channel %d busy\n", chan); #endif dma_busy |= (1 << chan); if (isa_dmarangecheck(addr, nbytes, chan)) { if (dma_bouncebuf[chan] == NULL || dma_bouncebufsize[chan] < nbytes) panic("isa_dmastart: bad bounce buffer"); dma_bounced |= (1 << chan); newaddr = dma_bouncebuf[chan]; /* copy bounce buffer on write */ if (flags & ISADMA_WRITE) bcopy(addr, newaddr, nbytes); addr = newaddr; } /* translate to physical */ phys = pmap_extract(&kernel_pmap, (vm_offset_t)addr); if (flags & ISADMA_RAW) { dma_auto_mode |= (1 << chan); } else { dma_auto_mode &= ~(1 << chan); } if ((chan & 4) == 0) { /* * Program one of DMA channels 0..3. These are * byte mode channels. */ /* set dma channel mode, and reset address ff */ /* If ISADMA_RAW flag is set, then use autoinitialise mode */ if (flags & ISADMA_RAW) { if (flags & ISADMA_READ) outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan); else outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan); } else if (flags & ISADMA_READ) outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan); else outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan); outb(DMA1_FFC, 0); /* send start address */ waport = DMA1_CHN(chan); outb(waport, phys); outb(waport, phys>>8); outb(dmapageport[chan], phys>>16); /* send count */ outb(waport + 1, --nbytes); outb(waport + 1, nbytes>>8); /* unmask channel */ outb(DMA1_SMSK, chan); } else { /* * Program one of DMA channels 4..7. These are * word mode channels. */ /* set dma channel mode, and reset address ff */ /* If ISADMA_RAW flag is set, then use autoinitialise mode */ if (flags & ISADMA_RAW) { if (flags & ISADMA_READ) outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3)); else outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3)); } else if (flags & ISADMA_READ) outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3)); else outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3)); outb(DMA2_FFC, 0); /* send start address */ waport = DMA2_CHN(chan - 4); outb(waport, phys>>1); outb(waport, phys>>9); outb(dmapageport[chan], phys>>16); /* send count */ nbytes >>= 1; outb(waport + 2, --nbytes); outb(waport + 2, nbytes>>8); /* unmask channel */ outb(DMA2_SMSK, chan & 3); } } void isa_dmadone(int flags, caddr_t addr, int nbytes, int chan) { #ifdef DIAGNOSTIC if (chan & ~VALID_DMA_MASK) panic("isa_dmadone: channel out of range"); if ((dma_inuse & (1 << chan)) == 0) kprintf("isa_dmadone: channel %d not acquired\n", chan); #endif if (((dma_busy & (1 << chan)) == 0) && (dma_auto_mode & (1 << chan)) == 0 ) kprintf("isa_dmadone: channel %d not busy\n", chan); if ((dma_auto_mode & (1 << chan)) == 0) outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4); if (dma_bounced & (1 << chan)) { /* copy bounce buffer on read */ if (flags & ISADMA_READ) bcopy(dma_bouncebuf[chan], addr, nbytes); dma_bounced &= ~(1 << chan); } dma_busy &= ~(1 << chan); } /* * Check for problems with the address range of a DMA transfer * (non-contiguous physical pages, outside of bus address space, * crossing DMA page boundaries). * Return true if special handling needed. */ static int isa_dmarangecheck(caddr_t va, u_int length, int chan) { vm_paddr_t phys, priorpage = 0; vm_offset_t endva; u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1); endva = (vm_offset_t)round_page((vm_offset_t)va + length); for (; va < (caddr_t) endva ; va += PAGE_SIZE) { phys = trunc_page(pmap_extract(&kernel_pmap, (vm_offset_t)va)); #define ISARAM_END RAM_END if (phys == 0) panic("isa_dmacheck: no physical page present"); if (phys >= ISARAM_END) return (1); if (priorpage) { if (priorpage + PAGE_SIZE != phys) return (1); /* check if crossing a DMA page boundary */ if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk) return (1); } priorpage = phys; } return (0); } /* * Query the progress of a transfer on a DMA channel. * * To avoid having to interrupt a transfer in progress, we sample * each of the high and low databytes twice, and apply the following * logic to determine the correct count. * * Reads are performed with interrupts disabled, thus it is to be * expected that the time between reads is very small. At most * one rollover in the low count byte can be expected within the * four reads that are performed. * * There are three gaps in which a rollover can occur : * * - read low1 * gap1 * - read high1 * gap2 * - read low2 * gap3 * - read high2 * * If a rollover occurs in gap1 or gap2, the low2 value will be * greater than the low1 value. In this case, low2 and high2 are a * corresponding pair. * * In any other case, low1 and high1 can be considered to be correct. * * The function returns the number of bytes remaining in the transfer, * or -1 if the channel requested is not active. * */ int isa_dmastatus(int chan) { u_long cnt = 0; int ffport, waport; u_long low1, high1, low2, high2; /* channel active? */ if ((dma_inuse & (1 << chan)) == 0) { kprintf("isa_dmastatus: channel %d not active\n", chan); return(-1); } /* channel busy? */ if (((dma_busy & (1 << chan)) == 0) && (dma_auto_mode & (1 << chan)) == 0 ) { kprintf("chan %d not busy\n", chan); return -2 ; } if (chan < 4) { /* low DMA controller */ ffport = DMA1_FFC; waport = DMA1_CHN(chan) + 1; } else { /* high DMA controller */ ffport = DMA2_FFC; waport = DMA2_CHN(chan - 4) + 2; } cpu_disable_intr(); /* YYY *//* no interrupts Mr Jones! */ outb(ffport, 0); /* clear register LSB flipflop */ low1 = inb(waport); high1 = inb(waport); outb(ffport, 0); /* clear again */ low2 = inb(waport); high2 = inb(waport); cpu_enable_intr(); /* enable interrupts again */ /* * Now decide if a wrap has tried to skew our results. * Note that after TC, the count will read 0xffff, while we want * to return zero, so we add and then mask to compensate. */ if (low1 >= low2) { cnt = (low1 + (high1 << 8) + 1) & 0xffff; } else { cnt = (low2 + (high2 << 8) + 1) & 0xffff; } if (chan >= 4) /* high channels move words */ cnt *= 2; return(cnt); } /* * Stop a DMA transfer currently in progress. */ int isa_dmastop(int chan) { if ((dma_inuse & (1 << chan)) == 0) kprintf("isa_dmastop: channel %d not acquired\n", chan); if (((dma_busy & (1 << chan)) == 0) && ((dma_auto_mode & (1 << chan)) == 0)) { kprintf("chan %d not busy\n", chan); return -2 ; } if ((chan & 4) == 0) { outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */); } else { outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */); } return(isa_dmastatus(chan)); } unsigned isa_dmabp(struct buf *bp) { unsigned flags = 0; KKASSERT(bp->b_cmd != BUF_CMD_DONE); if (bp->b_flags & B_RAW) flags |= ISADMA_RAW; if (bp->b_cmd == BUF_CMD_READ) { flags |= ISADMA_READ; } else { /* BUF_CMD_WRITE, BUF_CMD_FORMAT */ flags |= ISADMA_WRITE; } return(flags); }