diff options
Diffstat (limited to 'sys/x86/isa/isa_dma.c')
-rw-r--r-- | sys/x86/isa/isa_dma.c | 611 |
1 files changed, 611 insertions, 0 deletions
diff --git a/sys/x86/isa/isa_dma.c b/sys/x86/isa/isa_dma.c new file mode 100644 index 0000000..cbc9959 --- /dev/null +++ b/sys/x86/isa/isa_dma.c @@ -0,0 +1,611 @@ +/*- + * 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. + * 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 + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +/* + * 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 <sys/param.h> +#include <sys/systm.h> +#include <sys/bus.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/lock.h> +#include <sys/proc.h> +#include <sys/mutex.h> +#include <sys/module.h> +#include <vm/vm.h> +#include <vm/vm_param.h> +#include <vm/pmap.h> +#include <isa/isareg.h> +#include <isa/isavar.h> +#include <isa/isa_dmareg.h> + +#define ISARAM_END RAM_END + +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; +static struct mtx isa_dma_lock; +MTX_SYSINIT(isa_dma_lock, &isa_dma_lock, "isa DMA lock", MTX_DEF); + +#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. + */ +int +isa_dma_init(int chan, u_int bouncebufsize, int flag) +{ + void *buf; + int contig; + +#ifdef DIAGNOSTIC + if (chan & ~VALID_DMA_MASK) + panic("isa_dma_init: channel out of range"); +#endif + + + /* Try malloc() first. It works better if it works. */ + buf = malloc(bouncebufsize, M_DEVBUF, flag); + if (buf != NULL) { + if (isa_dmarangecheck(buf, bouncebufsize, chan) != 0) { + free(buf, M_DEVBUF); + buf = NULL; + } + contig = 0; + } + + if (buf == NULL) { + buf = contigmalloc(bouncebufsize, M_DEVBUF, flag, 0ul, 0xfffffful, + 1ul, chan & 4 ? 0x20000ul : 0x10000ul); + contig = 1; + } + + if (buf == NULL) + return (ENOMEM); + + mtx_lock(&isa_dma_lock); + /* + * If a DMA channel is shared, both drivers have to call isa_dma_init + * since they don't know that the other driver will do it. + * Just return if we're already set up good. + * XXX: this only works if they agree on the bouncebuf size. This + * XXX: is typically the case since they are multiple instances of + * XXX: the same driver. + */ + if (dma_bouncebuf[chan] != NULL) { + if (contig) + contigfree(buf, bouncebufsize, M_DEVBUF); + else + free(buf, M_DEVBUF); + mtx_unlock(&isa_dma_lock); + return (0); + } + + dma_bouncebufsize[chan] = bouncebufsize; + dma_bouncebuf[chan] = buf; + + mtx_unlock(&isa_dma_lock); + + return (0); +} + +/* + * Register a DMA channel's usage. Usually called from a device driver + * in open() or during its initialization. + */ +int +isa_dma_acquire(chan) + int chan; +{ +#ifdef DIAGNOSTIC + if (chan & ~VALID_DMA_MASK) + panic("isa_dma_acquire: channel out of range"); +#endif + + mtx_lock(&isa_dma_lock); + if (dma_inuse & (1 << chan)) { + printf("isa_dma_acquire: channel %d already in use\n", chan); + mtx_unlock(&isa_dma_lock); + return (EBUSY); + } + dma_inuse |= (1 << chan); + dma_auto_mode &= ~(1 << chan); + mtx_unlock(&isa_dma_lock); + + return (0); +} + +/* + * Unregister a DMA channel's usage. Usually called from a device driver + * during close() or during its shutdown. + */ +void +isa_dma_release(chan) + int chan; +{ +#ifdef DIAGNOSTIC + if (chan & ~VALID_DMA_MASK) + panic("isa_dma_release: channel out of range"); + + mtx_lock(&isa_dma_lock); + if ((dma_inuse & (1 << chan)) == 0) + printf("isa_dma_release: channel %d not in use\n", chan); +#else + mtx_lock(&isa_dma_lock); +#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); + + mtx_unlock(&isa_dma_lock); +} + +/* + * isa_dmacascade(): program 8237 DMA controller channel to accept + * external dma control by a board. + */ +void +isa_dmacascade(chan) + int chan; +{ +#ifdef DIAGNOSTIC + if (chan & ~VALID_DMA_MASK) + panic("isa_dmacascade: channel out of range"); +#endif + + mtx_lock(&isa_dma_lock); + /* 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); + } + mtx_unlock(&isa_dma_lock); +} + +/* + * 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; + int dma_range_checked; + + /* translate to physical */ + phys = pmap_extract(kernel_pmap, (vm_offset_t)addr); + dma_range_checked = isa_dmarangecheck(addr, nbytes, chan); + +#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) || (uintptr_t)addr & 1))) + panic("isa_dmastart: impossible request"); + + mtx_lock(&isa_dma_lock); + if ((dma_inuse & (1 << chan)) == 0) + printf("isa_dmastart: channel %d not acquired\n", chan); +#else + mtx_lock(&isa_dma_lock); +#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)) + printf("isa_dmastart: channel %d busy\n", chan); +#endif + + dma_busy |= (1 << chan); + + if (dma_range_checked) { + 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_READ)) + bcopy(addr, newaddr, nbytes); + addr = newaddr; + } + + 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); + } + mtx_unlock(&isa_dma_lock); +} + +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) + printf("isa_dmadone: channel %d not acquired\n", chan); +#endif + + mtx_lock(&isa_dma_lock); + if (((dma_busy & (1 << chan)) == 0) && + (dma_auto_mode & (1 << chan)) == 0 ) + printf("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); + mtx_unlock(&isa_dma_lock); +} + +/* + * 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)); + 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. + * + */ +static int +isa_dmastatus_locked(int chan) +{ + u_long cnt = 0; + int ffport, waport; + u_long low1, high1, low2, high2; + + mtx_assert(&isa_dma_lock, MA_OWNED); + + /* channel active? */ + if ((dma_inuse & (1 << chan)) == 0) { + printf("isa_dmastatus: channel %d not active\n", chan); + return(-1); + } + /* channel busy? */ + + if (((dma_busy & (1 << chan)) == 0) && + (dma_auto_mode & (1 << chan)) == 0 ) { + printf("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; + } + + disable_intr(); /* 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); + 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); +} + +int +isa_dmastatus(int chan) +{ + int status; + + mtx_lock(&isa_dma_lock); + status = isa_dmastatus_locked(chan); + mtx_unlock(&isa_dma_lock); + + return (status); +} + +/* + * Reached terminal count yet ? + */ +int +isa_dmatc(int chan) +{ + + if (chan < 4) + return(inb(DMA1_STATUS) & (1 << chan)); + else + return(inb(DMA2_STATUS) & (1 << (chan & 3))); +} + +/* + * Stop a DMA transfer currently in progress. + */ +int +isa_dmastop(int chan) +{ + int status; + + mtx_lock(&isa_dma_lock); + if ((dma_inuse & (1 << chan)) == 0) + printf("isa_dmastop: channel %d not acquired\n", chan); + + if (((dma_busy & (1 << chan)) == 0) && + ((dma_auto_mode & (1 << chan)) == 0)) { + printf("chan %d not busy\n", chan); + mtx_unlock(&isa_dma_lock); + return -2 ; + } + + if ((chan & 4) == 0) { + outb(DMA1_SMSK, (chan & 3) | 4 /* disable mask */); + } else { + outb(DMA2_SMSK, (chan & 3) | 4 /* disable mask */); + } + + status = isa_dmastatus_locked(chan); + + mtx_unlock(&isa_dma_lock); + + return (status); +} + +/* + * Attach to the ISA PnP descriptor for the AT DMA controller + */ +static struct isa_pnp_id atdma_ids[] = { + { 0x0002d041 /* PNP0200 */, "AT DMA controller" }, + { 0 } +}; + +static int +atdma_probe(device_t dev) +{ + int result; + + if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, atdma_ids)) <= 0) + device_quiet(dev); + return(result); +} + +static int +atdma_attach(device_t dev) +{ + return(0); +} + +static device_method_t atdma_methods[] = { + /* Device interface */ + DEVMETHOD(device_probe, atdma_probe), + DEVMETHOD(device_attach, atdma_attach), + DEVMETHOD(device_detach, bus_generic_detach), + DEVMETHOD(device_shutdown, bus_generic_shutdown), + DEVMETHOD(device_suspend, bus_generic_suspend), + DEVMETHOD(device_resume, bus_generic_resume), + { 0, 0 } +}; + +static driver_t atdma_driver = { + "atdma", + atdma_methods, + 1, /* no softc */ +}; + +static devclass_t atdma_devclass; + +DRIVER_MODULE(atdma, isa, atdma_driver, atdma_devclass, 0, 0); +DRIVER_MODULE(atdma, acpi, atdma_driver, atdma_devclass, 0, 0); |