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Diffstat (limited to 'sys/x86/isa/isa_dma.c')
-rw-r--r--sys/x86/isa/isa_dma.c611
1 files changed, 611 insertions, 0 deletions
diff --git a/sys/x86/isa/isa_dma.c b/sys/x86/isa/isa_dma.c
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+++ b/sys/x86/isa/isa_dma.c
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+/*-
+ * 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);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-19 05:20:33 +0000