isa_dma.c revision 204309
145720Speter/*- 245720Speter * Copyright (c) 1991 The Regents of the University of California. 345720Speter * All rights reserved. 445720Speter * 545720Speter * This code is derived from software contributed to Berkeley by 645720Speter * William Jolitz. 745720Speter * 845720Speter * Redistribution and use in source and binary forms, with or without 945720Speter * modification, are permitted provided that the following conditions 1045720Speter * are met: 1145720Speter * 1. Redistributions of source code must retain the above copyright 1245720Speter * notice, this list of conditions and the following disclaimer. 1345720Speter * 2. Redistributions in binary form must reproduce the above copyright 1445720Speter * notice, this list of conditions and the following disclaimer in the 1545720Speter * documentation and/or other materials provided with the distribution. 1645720Speter * 4. Neither the name of the University nor the names of its contributors 1745720Speter * may be used to endorse or promote products derived from this software 1845720Speter * without specific prior written permission. 1945720Speter * 2045720Speter * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2145720Speter * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2245720Speter * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2345720Speter * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2445720Speter * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2545720Speter * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2645720Speter * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2745720Speter * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2845720Speter * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2945720Speter * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3045720Speter * SUCH DAMAGE. 3145720Speter * 3245720Speter * from: @(#)isa.c 7.2 (Berkeley) 5/13/91 3345720Speter */ 3445720Speter 3545720Speter#include <sys/cdefs.h> 3645720Speter__FBSDID("$FreeBSD: head/sys/x86/isa/isa_dma.c 204309 2010-02-25 14:13:39Z attilio $"); 3750477Speter 3845720Speter/* 3945720Speter * code to manage AT bus 4045720Speter * 4145720Speter * 92/08/18 Frank P. MacLachlan (fpm@crash.cts.com): 4245720Speter * Fixed uninitialized variable problem and added code to deal 4345720Speter * with DMA page boundaries in isa_dmarangecheck(). Fixed word 4445720Speter * mode DMA count compution and reorganized DMA setup code in 4545720Speter * isa_dmastart() 4645720Speter */ 4745720Speter 4845720Speter#include <sys/param.h> 4945720Speter#include <sys/systm.h> 5045720Speter#include <sys/bus.h> 5145720Speter#include <sys/kernel.h> 5261994Smsmith#include <sys/malloc.h> 5361994Smsmith#include <sys/lock.h> 5445720Speter#include <sys/proc.h> 5561994Smsmith#include <sys/mutex.h> 5645720Speter#include <sys/module.h> 5745720Speter#include <vm/vm.h> 5845720Speter#include <vm/vm_param.h> 5945720Speter#include <vm/pmap.h> 6045720Speter#include <isa/isareg.h> 6161994Smsmith#include <isa/isavar.h> 6245720Speter#include <isa/isa_dmareg.h> 6345720Speter 6445720Speter#define ISARAM_END RAM_END 6545720Speter 6645720Speterstatic int isa_dmarangecheck(caddr_t va, u_int length, int chan); 6745720Speter 6845720Speterstatic caddr_t dma_bouncebuf[8]; 6945720Speterstatic u_int dma_bouncebufsize[8]; 7045720Speterstatic u_int8_t dma_bounced = 0; 7145720Speterstatic u_int8_t dma_busy = 0; /* Used in isa_dmastart() */ 7245720Speterstatic u_int8_t dma_inuse = 0; /* User for acquire/release */ 7345720Speterstatic u_int8_t dma_auto_mode = 0; 7445720Speterstatic struct mtx isa_dma_lock; 7545720SpeterMTX_SYSINIT(isa_dma_lock, &isa_dma_lock, "isa DMA lock", MTX_DEF); 7645720Speter 7745720Speter#define VALID_DMA_MASK (7) 7845720Speter 7945720Speter/* high byte of address is stored in this port for i-th dma channel */ 8045720Speterstatic int dmapageport[8] = { 0x87, 0x83, 0x81, 0x82, 0x8f, 0x8b, 0x89, 0x8a }; 8145720Speter 8245720Speter/* 8345720Speter * Setup a DMA channel's bounce buffer. 8445720Speter */ 8545720Speterint 8645720Speterisa_dma_init(int chan, u_int bouncebufsize, int flag) 8745720Speter{ 8845720Speter void *buf; 8945720Speter int contig; 9045720Speter 9145720Speter#ifdef DIAGNOSTIC 9245720Speter if (chan & ~VALID_DMA_MASK) 9345720Speter panic("isa_dma_init: channel out of range"); 9445720Speter#endif 9545720Speter 9645720Speter 9745720Speter /* Try malloc() first. It works better if it works. */ 9845720Speter buf = malloc(bouncebufsize, M_DEVBUF, flag); 9945720Speter if (buf != NULL) { 10045720Speter if (isa_dmarangecheck(buf, bouncebufsize, chan) != 0) { 10145720Speter free(buf, M_DEVBUF); 10245720Speter buf = NULL; 10345720Speter } 10445720Speter contig = 0; 10545720Speter } 10645720Speter 10745720Speter if (buf == NULL) { 10845720Speter buf = contigmalloc(bouncebufsize, M_DEVBUF, flag, 0ul, 0xfffffful, 10945720Speter 1ul, chan & 4 ? 0x20000ul : 0x10000ul); 11045720Speter contig = 1; 11145720Speter } 11245720Speter 11345720Speter if (buf == NULL) 11445720Speter return (ENOMEM); 11545720Speter 11645720Speter mtx_lock(&isa_dma_lock); 11745720Speter /* 11845720Speter * If a DMA channel is shared, both drivers have to call isa_dma_init 11945720Speter * since they don't know that the other driver will do it. 12045720Speter * Just return if we're already set up good. 12145720Speter * XXX: this only works if they agree on the bouncebuf size. This 12245720Speter * XXX: is typically the case since they are multiple instances of 12345720Speter * XXX: the same driver. 12445720Speter */ 12545720Speter if (dma_bouncebuf[chan] != NULL) { 12645720Speter if (contig) 12745720Speter contigfree(buf, bouncebufsize, M_DEVBUF); 12845720Speter else 12945720Speter free(buf, M_DEVBUF); 13045720Speter mtx_unlock(&isa_dma_lock); 13145720Speter return (0); 13245720Speter } 13345720Speter 13445720Speter dma_bouncebufsize[chan] = bouncebufsize; 13545720Speter dma_bouncebuf[chan] = buf; 13645720Speter 13745720Speter mtx_unlock(&isa_dma_lock); 13845720Speter 13945720Speter return (0); 14045720Speter} 14145720Speter 14245720Speter/* 14345720Speter * Register a DMA channel's usage. Usually called from a device driver 14445720Speter * in open() or during its initialization. 14545720Speter */ 14645720Speterint 14745720Speterisa_dma_acquire(chan) 14845720Speter int chan; 14945720Speter{ 15045720Speter#ifdef DIAGNOSTIC 15145720Speter if (chan & ~VALID_DMA_MASK) 15245720Speter panic("isa_dma_acquire: channel out of range"); 15345720Speter#endif 15445720Speter 15545720Speter mtx_lock(&isa_dma_lock); 15645720Speter if (dma_inuse & (1 << chan)) { 15745720Speter printf("isa_dma_acquire: channel %d already in use\n", chan); 15845720Speter mtx_unlock(&isa_dma_lock); 15945720Speter return (EBUSY); 16045720Speter } 16145720Speter dma_inuse |= (1 << chan); 16245720Speter dma_auto_mode &= ~(1 << chan); 16345720Speter mtx_unlock(&isa_dma_lock); 16445720Speter 16545720Speter return (0); 16645720Speter} 16745720Speter 16845720Speter/* 16945720Speter * Unregister a DMA channel's usage. Usually called from a device driver 17045720Speter * during close() or during its shutdown. 17145720Speter */ 17245720Spetervoid 17345720Speterisa_dma_release(chan) 17445720Speter int chan; 17545720Speter{ 17645720Speter#ifdef DIAGNOSTIC 17745720Speter if (chan & ~VALID_DMA_MASK) 17845720Speter panic("isa_dma_release: channel out of range"); 17945720Speter 18045720Speter mtx_lock(&isa_dma_lock); 18145720Speter if ((dma_inuse & (1 << chan)) == 0) 18245720Speter printf("isa_dma_release: channel %d not in use\n", chan); 18345720Speter#else 18445720Speter mtx_lock(&isa_dma_lock); 18545720Speter#endif 18645720Speter 18745720Speter if (dma_busy & (1 << chan)) { 18845720Speter dma_busy &= ~(1 << chan); 18945720Speter /* 19045720Speter * XXX We should also do "dma_bounced &= (1 << chan);" 19145720Speter * because we are acting on behalf of isa_dmadone() which 19245720Speter * was not called to end the last DMA operation. This does 19345720Speter * not matter now, but it may in the future. 19445720Speter */ 19545720Speter } 19645720Speter 19745720Speter dma_inuse &= ~(1 << chan); 19845720Speter dma_auto_mode &= ~(1 << chan); 19945720Speter 20045720Speter mtx_unlock(&isa_dma_lock); 20145720Speter} 20245720Speter 20345720Speter/* 20445720Speter * isa_dmacascade(): program 8237 DMA controller channel to accept 20545720Speter * external dma control by a board. 20645720Speter */ 20745720Spetervoid 20845720Speterisa_dmacascade(chan) 20945720Speter int chan; 21045720Speter{ 21145720Speter#ifdef DIAGNOSTIC 21245720Speter if (chan & ~VALID_DMA_MASK) 21345720Speter panic("isa_dmacascade: channel out of range"); 21445720Speter#endif 21545720Speter 21645720Speter mtx_lock(&isa_dma_lock); 21745720Speter /* set dma channel mode, and set dma channel mode */ 21845720Speter if ((chan & 4) == 0) { 21945720Speter outb(DMA1_MODE, DMA37MD_CASCADE | chan); 22045720Speter outb(DMA1_SMSK, chan); 22145720Speter } else { 22245720Speter outb(DMA2_MODE, DMA37MD_CASCADE | (chan & 3)); 22345720Speter outb(DMA2_SMSK, chan & 3); 22445720Speter } 22545720Speter mtx_unlock(&isa_dma_lock); 22645720Speter} 22745720Speter 22845720Speter/* 22945720Speter * isa_dmastart(): program 8237 DMA controller channel, avoid page alignment 23045720Speter * problems by using a bounce buffer. 23145720Speter */ 23245720Spetervoid 23345720Speterisa_dmastart(int flags, caddr_t addr, u_int nbytes, int chan) 23445720Speter{ 23545720Speter vm_paddr_t phys; 23645720Speter int waport; 23745720Speter caddr_t newaddr; 23845720Speter int dma_range_checked; 23945720Speter 24045720Speter /* translate to physical */ 24145720Speter phys = pmap_extract(kernel_pmap, (vm_offset_t)addr); 24245720Speter dma_range_checked = isa_dmarangecheck(addr, nbytes, chan); 24345720Speter 24445720Speter#ifdef DIAGNOSTIC 24545720Speter if (chan & ~VALID_DMA_MASK) 24645720Speter panic("isa_dmastart: channel out of range"); 24745720Speter 24845720Speter if ((chan < 4 && nbytes > (1<<16)) 24957973Sphk || (chan >= 4 && (nbytes > (1<<17) || (uintptr_t)addr & 1))) 25045720Speter panic("isa_dmastart: impossible request"); 25145720Speter 25245720Speter mtx_lock(&isa_dma_lock); 25345720Speter if ((dma_inuse & (1 << chan)) == 0) 25445720Speter printf("isa_dmastart: channel %d not acquired\n", chan); 25545720Speter#else 25645720Speter mtx_lock(&isa_dma_lock); 25757973Sphk#endif 25845720Speter 25945720Speter#if 0 26045720Speter /* 26145720Speter * XXX This should be checked, but drivers like ad1848 only call 26245720Speter * isa_dmastart() once because they use Auto DMA mode. If we 26345720Speter * leave this in, drivers that do this will print this continuously. 26445720Speter */ 26545720Speter if (dma_busy & (1 << chan)) 26645720Speter printf("isa_dmastart: channel %d busy\n", chan); 26745720Speter#endif 26845720Speter 26945720Speter dma_busy |= (1 << chan); 27057973Sphk 27157973Sphk if (dma_range_checked) { 27257973Sphk if (dma_bouncebuf[chan] == NULL 27345720Speter || dma_bouncebufsize[chan] < nbytes) 27445720Speter panic("isa_dmastart: bad bounce buffer"); 27545720Speter dma_bounced |= (1 << chan); 27645720Speter newaddr = dma_bouncebuf[chan]; 27745720Speter 27857973Sphk /* copy bounce buffer on write */ 27945720Speter if (!(flags & ISADMA_READ)) 28045720Speter bcopy(addr, newaddr, nbytes); 28145720Speter addr = newaddr; 28245720Speter } 28345720Speter 28445720Speter if (flags & ISADMA_RAW) { 28545720Speter dma_auto_mode |= (1 << chan); 28645720Speter } else { 28745720Speter dma_auto_mode &= ~(1 << chan); 28845720Speter } 28945720Speter 29045720Speter if ((chan & 4) == 0) { 29145720Speter /* 29245720Speter * Program one of DMA channels 0..3. These are 29345720Speter * byte mode channels. 29445720Speter */ 29545720Speter /* set dma channel mode, and reset address ff */ 29645720Speter 29745720Speter /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 29845720Speter if (flags & ISADMA_RAW) { 29945720Speter if (flags & ISADMA_READ) 30045720Speter outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_WRITE|chan); 30145720Speter else 30245720Speter outb(DMA1_MODE, DMA37MD_AUTO|DMA37MD_READ|chan); 30357973Sphk } 30457973Sphk else 30557973Sphk if (flags & ISADMA_READ) 30645720Speter outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|chan); 30745720Speter else 30845720Speter outb(DMA1_MODE, DMA37MD_SINGLE|DMA37MD_READ|chan); 30945720Speter outb(DMA1_FFC, 0); 31045720Speter 31157973Sphk /* send start address */ 31245720Speter waport = DMA1_CHN(chan); 31345720Speter outb(waport, phys); 31445720Speter outb(waport, phys>>8); 31545720Speter outb(dmapageport[chan], phys>>16); 31645720Speter 31745720Speter /* send count */ 31845720Speter outb(waport + 1, --nbytes); 31945720Speter outb(waport + 1, nbytes>>8); 32045720Speter 32145720Speter /* unmask channel */ 32245720Speter outb(DMA1_SMSK, chan); 32345720Speter } else { 32445720Speter /* 32545720Speter * Program one of DMA channels 4..7. These are 32645720Speter * word mode channels. 32745720Speter */ 32845720Speter /* set dma channel mode, and reset address ff */ 32945720Speter 33045720Speter /* If ISADMA_RAW flag is set, then use autoinitialise mode */ 33145720Speter if (flags & ISADMA_RAW) { 33245720Speter if (flags & ISADMA_READ) 33345720Speter outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_WRITE|(chan&3)); 33445720Speter else 33545720Speter outb(DMA2_MODE, DMA37MD_AUTO|DMA37MD_READ|(chan&3)); 33645720Speter } 33745720Speter else 33845720Speter if (flags & ISADMA_READ) 33945720Speter outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_WRITE|(chan&3)); 34045720Speter else 34145720Speter outb(DMA2_MODE, DMA37MD_SINGLE|DMA37MD_READ|(chan&3)); 34245720Speter outb(DMA2_FFC, 0); 34345720Speter 34445720Speter /* send start address */ 34545720Speter waport = DMA2_CHN(chan - 4); 34645720Speter outb(waport, phys>>1); 34745720Speter outb(waport, phys>>9); 34845720Speter outb(dmapageport[chan], phys>>16); 34945720Speter 35045720Speter /* send count */ 35145720Speter nbytes >>= 1; 35245720Speter outb(waport + 2, --nbytes); 35357973Sphk outb(waport + 2, nbytes>>8); 35445720Speter 35545720Speter /* unmask channel */ 35645720Speter outb(DMA2_SMSK, chan & 3); 35745720Speter } 35845720Speter mtx_unlock(&isa_dma_lock); 35945720Speter} 36045720Speter 36145720Spetervoid 36245720Speterisa_dmadone(int flags, caddr_t addr, int nbytes, int chan) 36345720Speter{ 36445720Speter#ifdef DIAGNOSTIC 36545720Speter if (chan & ~VALID_DMA_MASK) 36645720Speter panic("isa_dmadone: channel out of range"); 36745720Speter 36845720Speter if ((dma_inuse & (1 << chan)) == 0) 36945720Speter printf("isa_dmadone: channel %d not acquired\n", chan); 37045720Speter#endif 37145720Speter 37245720Speter mtx_lock(&isa_dma_lock); 37345720Speter if (((dma_busy & (1 << chan)) == 0) && 37445720Speter (dma_auto_mode & (1 << chan)) == 0 ) 37545720Speter printf("isa_dmadone: channel %d not busy\n", chan); 37645720Speter 37745720Speter if ((dma_auto_mode & (1 << chan)) == 0) 37845720Speter outb(chan & 4 ? DMA2_SMSK : DMA1_SMSK, (chan & 3) | 4); 37945720Speter 38045720Speter if (dma_bounced & (1 << chan)) { 38145720Speter /* copy bounce buffer on read */ 38245720Speter if (flags & ISADMA_READ) 38345720Speter bcopy(dma_bouncebuf[chan], addr, nbytes); 38445720Speter 38545720Speter dma_bounced &= ~(1 << chan); 38645720Speter } 38745720Speter dma_busy &= ~(1 << chan); 38845720Speter mtx_unlock(&isa_dma_lock); 38945720Speter} 39045720Speter 39145720Speter/* 39245720Speter * Check for problems with the address range of a DMA transfer 39345720Speter * (non-contiguous physical pages, outside of bus address space, 39445720Speter * crossing DMA page boundaries). 39545720Speter * Return true if special handling needed. 39645720Speter */ 39745720Speter 39845720Speterstatic int 39945720Speterisa_dmarangecheck(caddr_t va, u_int length, int chan) 40045720Speter{ 40145720Speter vm_paddr_t phys, priorpage = 0; 40245720Speter vm_offset_t endva; 40345720Speter u_int dma_pgmsk = (chan & 4) ? ~(128*1024-1) : ~(64*1024-1); 40445720Speter 40545720Speter endva = (vm_offset_t)round_page((vm_offset_t)va + length); 40645720Speter for (; va < (caddr_t) endva ; va += PAGE_SIZE) { 40745720Speter phys = trunc_page(pmap_extract(kernel_pmap, (vm_offset_t)va)); 40845720Speter if (phys == 0) 40945720Speter panic("isa_dmacheck: no physical page present"); 41045720Speter if (phys >= ISARAM_END) 41145720Speter return (1); 41245720Speter if (priorpage) { 41345720Speter if (priorpage + PAGE_SIZE != phys) 41445720Speter return (1); 41545720Speter /* check if crossing a DMA page boundary */ 41645720Speter if (((u_int)priorpage ^ (u_int)phys) & dma_pgmsk) 41745720Speter return (1); 41845720Speter } 41945720Speter priorpage = phys; 42045720Speter } 42145720Speter return (0); 42245720Speter} 42345720Speter 42445720Speter/* 42545720Speter * Query the progress of a transfer on a DMA channel. 42645720Speter * 42745720Speter * To avoid having to interrupt a transfer in progress, we sample 42845720Speter * each of the high and low databytes twice, and apply the following 42945720Speter * logic to determine the correct count. 43045720Speter * 43145720Speter * Reads are performed with interrupts disabled, thus it is to be 43245720Speter * expected that the time between reads is very small. At most 43345720Speter * one rollover in the low count byte can be expected within the 43445720Speter * four reads that are performed. 43545720Speter * 43645720Speter * There are three gaps in which a rollover can occur : 43745720Speter * 43845720Speter * - read low1 43945720Speter * gap1 44045720Speter * - read high1 44145720Speter * gap2 44245720Speter * - read low2 44345720Speter * gap3 44445720Speter * - read high2 44545720Speter * 44645720Speter * If a rollover occurs in gap1 or gap2, the low2 value will be 44745720Speter * greater than the low1 value. In this case, low2 and high2 are a 44845720Speter * corresponding pair. 44945720Speter * 45045720Speter * In any other case, low1 and high1 can be considered to be correct. 45145720Speter * 45245720Speter * The function returns the number of bytes remaining in the transfer, 45345720Speter * or -1 if the channel requested is not active. 45445720Speter * 45545720Speter */ 45645720Speterstatic int 45745720Speterisa_dmastatus_locked(int chan) 45845720Speter{ 45945720Speter u_long cnt = 0; 46045720Speter int ffport, waport; 46145720Speter u_long low1, high1, low2, high2; 46245720Speter 46345720Speter mtx_assert(&isa_dma_lock, MA_OWNED); 46445720Speter 46545720Speter /* channel active? */ 46645720Speter if ((dma_inuse & (1 << chan)) == 0) { 46745720Speter printf("isa_dmastatus: channel %d not active\n", chan); 46845720Speter return(-1); 46945720Speter } 47045720Speter /* channel busy? */ 47145720Speter 47245720Speter if (((dma_busy & (1 << chan)) == 0) && 47345720Speter (dma_auto_mode & (1 << chan)) == 0 ) { 47445720Speter printf("chan %d not busy\n", chan); 47545720Speter return -2 ; 47645720Speter } 47745720Speter if (chan < 4) { /* low DMA controller */ 47845720Speter ffport = DMA1_FFC; 47945720Speter waport = DMA1_CHN(chan) + 1; 48045720Speter } else { /* high DMA controller */ 48145720Speter ffport = DMA2_FFC; 48245720Speter waport = DMA2_CHN(chan - 4) + 2; 48345720Speter } 48445720Speter 48545720Speter disable_intr(); /* no interrupts Mr Jones! */ 48645720Speter outb(ffport, 0); /* clear register LSB flipflop */ 48745720Speter low1 = inb(waport); 48845720Speter high1 = inb(waport); 48945720Speter outb(ffport, 0); /* clear again */ 49045720Speter low2 = inb(waport); 49145720Speter high2 = inb(waport); 49245720Speter enable_intr(); /* enable interrupts again */ 49345720Speter 49445720Speter /* 49545720Speter * Now decide if a wrap has tried to skew our results. 49645720Speter * Note that after TC, the count will read 0xffff, while we want 49745720Speter * to return zero, so we add and then mask to compensate. 49845720Speter */ 49945720Speter if (low1 >= low2) { 50061994Smsmith cnt = (low1 + (high1 << 8) + 1) & 0xffff; 50161994Smsmith } else { 50261994Smsmith cnt = (low2 + (high2 << 8) + 1) & 0xffff; 50361994Smsmith } 50461994Smsmith 50561994Smsmith if (chan >= 4) /* high channels move words */ 50661994Smsmith cnt *= 2; 50761994Smsmith return(cnt); 50861994Smsmith} 50961994Smsmith 51061994Smsmithint 51161994Smsmithisa_dmastatus(int chan) 51261994Smsmith{ 51361994Smsmith int status; 51461994Smsmith 51561994Smsmith mtx_lock(&isa_dma_lock); 51661994Smsmith status = isa_dmastatus_locked(chan); 51761994Smsmith mtx_unlock(&isa_dma_lock); 51861994Smsmith 51961994Smsmith return (status); 52061994Smsmith} 52161994Smsmith 52261994Smsmith/* 52361994Smsmith * Reached terminal count yet ? 52461994Smsmith */ 52561994Smsmithint 52661994Smsmithisa_dmatc(int chan) 52761994Smsmith{ 52861994Smsmith 52961994Smsmith if (chan < 4) 53061994Smsmith return(inb(DMA1_STATUS) & (1 << chan)); 53161994Smsmith else 53261994Smsmith return(inb(DMA2_STATUS) & (1 << (chan & 3))); 53361994Smsmith} 53461994Smsmith 53561994Smsmith/* 53661994Smsmith * Stop a DMA transfer currently in progress. 53761994Smsmith */ 53861994Smsmithint 53961994Smsmithisa_dmastop(int chan) 54061994Smsmith{ 54161994Smsmith int status; 54261994Smsmith 54361994Smsmith mtx_lock(&isa_dma_lock); 54461994Smsmith if ((dma_inuse & (1 << chan)) == 0) 545 printf("isa_dmastop: channel %d not acquired\n", chan); 546 547 if (((dma_busy & (1 << chan)) == 0) && 548 ((dma_auto_mode & (1 << chan)) == 0)) { 549 printf("chan %d not busy\n", chan); 550 mtx_unlock(&isa_dma_lock); 551 return -2 ; 552 } 553 554 if ((chan & 4) == 0) { 555 outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */); 556 } else { 557 outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */); 558 } 559 560 status = isa_dmastatus_locked(chan); 561 562 mtx_unlock(&isa_dma_lock); 563 564 return (status); 565} 566 567/* 568 * Attach to the ISA PnP descriptor for the AT DMA controller 569 */ 570static struct isa_pnp_id atdma_ids[] = { 571 { 0x0002d041 /* PNP0200 */, "AT DMA controller" }, 572 { 0 } 573}; 574 575static int 576atdma_probe(device_t dev) 577{ 578 int result; 579 580 if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0) 581 device_quiet(dev); 582 return(result); 583} 584 585static int 586atdma_attach(device_t dev) 587{ 588 return(0); 589} 590 591static device_method_t atdma_methods[] = { 592 /* Device interface */ 593 DEVMETHOD(device_probe, atdma_probe), 594 DEVMETHOD(device_attach, atdma_attach), 595 DEVMETHOD(device_detach, bus_generic_detach), 596 DEVMETHOD(device_shutdown, bus_generic_shutdown), 597 DEVMETHOD(device_suspend, bus_generic_suspend), 598 DEVMETHOD(device_resume, bus_generic_resume), 599 { 0, 0 } 600}; 601 602static driver_t atdma_driver = { 603 "atdma", 604 atdma_methods, 605 1, /* no softc */ 606}; 607 608static devclass_t atdma_devclass; 609 610DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0); 611DRIVER_MODULE(atdma, acpi, atdma_driver, atdma_devclass, 0, 0); 612