freebsd-dev/sys/dev/esp/esp_pci.c

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/*-
* Copyright (c) 2011 Marius Strobl <marius@FreeBSD.org>
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/* $NetBSD: pcscp.c,v 1.45 2010/11/13 13:52:08 uebayasi Exp $ */
/*-
* Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center; Izumi Tsutsui.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* esp_pci.c: device dependent code for AMD Am53c974 (PCscsi-PCI)
* written by Izumi Tsutsui <tsutsui@NetBSD.org>
*
* Technical manual available at
* http://www.amd.com/files/connectivitysolutions/networking/archivednetworking/19113.pdf
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/resource.h>
#include <sys/rman.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <cam/scsi/scsi_all.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/esp/ncr53c9xreg.h>
#include <dev/esp/ncr53c9xvar.h>
#include <dev/esp/am53c974reg.h>
#define PCI_DEVICE_ID_AMD53C974 0x20201022
struct esp_pci_softc {
struct ncr53c9x_softc sc_ncr53c9x; /* glue to MI code */
device_t sc_dev;
struct resource *sc_res[2];
#define ESP_PCI_RES_INTR 0
#define ESP_PCI_RES_IO 1
bus_dma_tag_t sc_pdmat;
bus_dma_tag_t sc_xferdmat; /* DMA tag for transfers */
bus_dmamap_t sc_xferdmam; /* DMA map for transfers */
void *sc_ih; /* interrupt handler */
size_t sc_dmasize; /* DMA size */
void **sc_dmaaddr; /* DMA address */
size_t *sc_dmalen; /* DMA length */
int sc_active; /* DMA state */
int sc_datain; /* DMA Data Direction */
};
static struct resource_spec esp_pci_res_spec[] = {
{ SYS_RES_IRQ, 0, RF_SHAREABLE | RF_ACTIVE }, /* ESP_PCI_RES_INTR */
{ SYS_RES_IOPORT, PCIR_BAR(0), RF_ACTIVE }, /* ESP_PCI_RES_IO */
{ -1, 0 }
};
#define READ_DMAREG(sc, reg) \
bus_read_4((sc)->sc_res[ESP_PCI_RES_IO], (reg))
#define WRITE_DMAREG(sc, reg, var) \
bus_write_4((sc)->sc_res[ESP_PCI_RES_IO], (reg), (var))
#define READ_ESPREG(sc, reg) \
bus_read_1((sc)->sc_res[ESP_PCI_RES_IO], (reg) << 2)
#define WRITE_ESPREG(sc, reg, val) \
bus_write_1((sc)->sc_res[ESP_PCI_RES_IO], (reg) << 2, (val))
static int esp_pci_probe(device_t);
static int esp_pci_attach(device_t);
static int esp_pci_detach(device_t);
static int esp_pci_suspend(device_t);
static int esp_pci_resume(device_t);
static device_method_t esp_pci_methods[] = {
DEVMETHOD(device_probe, esp_pci_probe),
DEVMETHOD(device_attach, esp_pci_attach),
DEVMETHOD(device_detach, esp_pci_detach),
DEVMETHOD(device_suspend, esp_pci_suspend),
DEVMETHOD(device_resume, esp_pci_resume),
DEVMETHOD_END
};
static driver_t esp_pci_driver = {
"esp",
esp_pci_methods,
sizeof(struct esp_pci_softc)
};
DRIVER_MODULE(esp, pci, esp_pci_driver, esp_devclass, 0, 0);
MODULE_DEPEND(esp, pci, 1, 1, 1);
/*
* Functions and the switch for the MI code
*/
static void esp_pci_dma_go(struct ncr53c9x_softc *);
static int esp_pci_dma_intr(struct ncr53c9x_softc *);
static int esp_pci_dma_isactive(struct ncr53c9x_softc *);
static int esp_pci_dma_isintr(struct ncr53c9x_softc *);
static void esp_pci_dma_reset(struct ncr53c9x_softc *);
static int esp_pci_dma_setup(struct ncr53c9x_softc *, void **, size_t *,
int, size_t *);
static void esp_pci_dma_stop(struct ncr53c9x_softc *);
static void esp_pci_write_reg(struct ncr53c9x_softc *, int, uint8_t);
static uint8_t esp_pci_read_reg(struct ncr53c9x_softc *, int);
static void esp_pci_xfermap(void *arg, bus_dma_segment_t *segs, int nseg,
int error);
static struct ncr53c9x_glue esp_pci_glue = {
esp_pci_read_reg,
esp_pci_write_reg,
esp_pci_dma_isintr,
esp_pci_dma_reset,
esp_pci_dma_intr,
esp_pci_dma_setup,
esp_pci_dma_go,
esp_pci_dma_stop,
esp_pci_dma_isactive,
};
static int
esp_pci_probe(device_t dev)
{
if (pci_get_devid(dev) == PCI_DEVICE_ID_AMD53C974) {
device_set_desc(dev, "AMD Am53C974 Fast-SCSI");
return (BUS_PROBE_DEFAULT);
}
return (ENXIO);
}
/*
* Attach this instance, and then all the sub-devices
*/
static int
esp_pci_attach(device_t dev)
{
struct esp_pci_softc *esc;
struct ncr53c9x_softc *sc;
int error;
esc = device_get_softc(dev);
sc = &esc->sc_ncr53c9x;
NCR_LOCK_INIT(sc);
esc->sc_dev = dev;
sc->sc_glue = &esp_pci_glue;
pci_enable_busmaster(dev);
error = bus_alloc_resources(dev, esp_pci_res_spec, esc->sc_res);
if (error != 0) {
device_printf(dev, "failed to allocate resources\n");
bus_release_resources(dev, esp_pci_res_spec, esc->sc_res);
return (error);
}
error = bus_dma_tag_create(bus_get_dma_tag(dev), 1, 0,
BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
BUS_SPACE_MAXSIZE_32BIT, BUS_SPACE_UNRESTRICTED,
BUS_SPACE_MAXSIZE_32BIT, 0, NULL, NULL, &esc->sc_pdmat);
if (error != 0) {
device_printf(dev, "cannot create parent DMA tag\n");
goto fail_res;
}
/*
* XXX More of this should be in ncr53c9x_attach(), but
* XXX should we really poke around the chip that much in
* XXX the MI code? Think about this more...
*/
/*
* Set up static configuration info.
*
* XXX we should read the configuration from the EEPROM.
*/
sc->sc_id = 7;
sc->sc_cfg1 = sc->sc_id | NCRCFG1_PARENB;
sc->sc_cfg2 = NCRCFG2_SCSI2 | NCRCFG2_FE;
sc->sc_cfg3 = NCRAMDCFG3_IDM | NCRAMDCFG3_FCLK;
sc->sc_cfg4 = NCRAMDCFG4_GE12NS | NCRAMDCFG4_RADE;
sc->sc_rev = NCR_VARIANT_AM53C974;
sc->sc_features = NCR_F_FASTSCSI | NCR_F_DMASELECT;
sc->sc_cfg3_fscsi = NCRAMDCFG3_FSCSI;
sc->sc_freq = 40; /* MHz */
/*
* This is the value used to start sync negotiations
* Note that the NCR register "SYNCTP" is programmed
* in "clocks per byte", and has a minimum value of 4.
* The SCSI period used in negotiation is one-fourth
* of the time (in nanoseconds) needed to transfer one byte.
* Since the chip's clock is given in MHz, we have the following
* formula: 4 * period = (1000 / freq) * 4
*/
sc->sc_minsync = 1000 / sc->sc_freq;
sc->sc_maxxfer = DFLTPHYS; /* see below */
sc->sc_maxoffset = 15;
sc->sc_extended_geom = 1;
#define MDL_SEG_SIZE 0x1000 /* 4kbyte per segment */
/*
* Create the DMA tag and map for the data transfers.
*
* Note: given that bus_dma(9) only adheres to the requested alignment
* for the first segment (and that also only for bus_dmamem_alloc()ed
* DMA maps) we can't use the Memory Descriptor List. However, also
* when not using the MDL, the maximum transfer size apparently is
* limited to 4k so we have to split transfers up, which plain sucks.
*/
error = bus_dma_tag_create(esc->sc_pdmat, PAGE_SIZE, 0,
BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
MDL_SEG_SIZE, 1, MDL_SEG_SIZE, BUS_DMA_ALLOCNOW,
busdma_lock_mutex, &sc->sc_lock, &esc->sc_xferdmat);
if (error != 0) {
device_printf(dev, "cannot create transfer DMA tag\n");
goto fail_pdmat;
}
error = bus_dmamap_create(esc->sc_xferdmat, 0, &esc->sc_xferdmam);
if (error != 0) {
device_printf(dev, "cannot create transfer DMA map\n");
goto fail_xferdmat;
}
error = bus_setup_intr(dev, esc->sc_res[ESP_PCI_RES_INTR],
INTR_MPSAFE | INTR_TYPE_CAM, NULL, ncr53c9x_intr, sc,
&esc->sc_ih);
if (error != 0) {
device_printf(dev, "cannot set up interrupt\n");
goto fail_xferdmam;
}
/* Do the common parts of attachment. */
sc->sc_dev = esc->sc_dev;
error = ncr53c9x_attach(sc);
if (error != 0) {
device_printf(esc->sc_dev, "ncr53c9x_attach failed\n");
goto fail_intr;
}
return (0);
fail_intr:
bus_teardown_intr(esc->sc_dev, esc->sc_res[ESP_PCI_RES_INTR],
esc->sc_ih);
fail_xferdmam:
bus_dmamap_destroy(esc->sc_xferdmat, esc->sc_xferdmam);
fail_xferdmat:
bus_dma_tag_destroy(esc->sc_xferdmat);
fail_pdmat:
bus_dma_tag_destroy(esc->sc_pdmat);
fail_res:
bus_release_resources(dev, esp_pci_res_spec, esc->sc_res);
NCR_LOCK_DESTROY(sc);
return (error);
}
static int
esp_pci_detach(device_t dev)
{
struct ncr53c9x_softc *sc;
struct esp_pci_softc *esc;
int error;
esc = device_get_softc(dev);
sc = &esc->sc_ncr53c9x;
bus_teardown_intr(esc->sc_dev, esc->sc_res[ESP_PCI_RES_INTR],
esc->sc_ih);
error = ncr53c9x_detach(sc);
if (error != 0)
return (error);
bus_dmamap_destroy(esc->sc_xferdmat, esc->sc_xferdmam);
bus_dma_tag_destroy(esc->sc_xferdmat);
bus_dma_tag_destroy(esc->sc_pdmat);
bus_release_resources(dev, esp_pci_res_spec, esc->sc_res);
NCR_LOCK_DESTROY(sc);
return (0);
}
static int
esp_pci_suspend(device_t dev)
{
return (ENXIO);
}
static int
esp_pci_resume(device_t dev)
{
return (ENXIO);
}
static void
esp_pci_xfermap(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)arg;
if (error != 0)
return;
KASSERT(nsegs == 1, ("%s: bad transfer segment count %d", __func__,
nsegs));
KASSERT(segs[0].ds_len <= MDL_SEG_SIZE,
("%s: bad transfer segment length %ld", __func__,
(long)segs[0].ds_len));
/* Program the DMA Starting Physical Address. */
WRITE_DMAREG(esc, DMA_SPA, segs[0].ds_addr);
}
/*
* Glue functions
*/
static uint8_t
esp_pci_read_reg(struct ncr53c9x_softc *sc, int reg)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
return (READ_ESPREG(esc, reg));
}
static void
esp_pci_write_reg(struct ncr53c9x_softc *sc, int reg, uint8_t v)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
WRITE_ESPREG(esc, reg, v);
}
static int
esp_pci_dma_isintr(struct ncr53c9x_softc *sc)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
return (READ_ESPREG(esc, NCR_STAT) & NCRSTAT_INT) != 0;
}
static void
esp_pci_dma_reset(struct ncr53c9x_softc *sc)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE);
esc->sc_active = 0;
}
static int
esp_pci_dma_intr(struct ncr53c9x_softc *sc)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
bus_dma_tag_t xferdmat;
bus_dmamap_t xferdmam;
size_t dmasize;
int datain, i, resid, trans;
uint32_t dmastat;
char *p = NULL;
xferdmat = esc->sc_xferdmat;
xferdmam = esc->sc_xferdmam;
datain = esc->sc_datain;
dmastat = READ_DMAREG(esc, DMA_STAT);
if ((dmastat & DMASTAT_ERR) != 0) {
/* XXX not tested... */
WRITE_DMAREG(esc, DMA_CMD, DMACMD_ABORT | (datain != 0 ?
DMACMD_DIR : 0));
device_printf(esc->sc_dev, "DMA error detected; Aborting.\n");
bus_dmamap_sync(xferdmat, xferdmam, datain != 0 ?
BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
bus_dmamap_unload(xferdmat, xferdmam);
return (-1);
}
if ((dmastat & DMASTAT_ABT) != 0) {
/* XXX what should be done? */
device_printf(esc->sc_dev, "DMA aborted.\n");
WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | (datain != 0 ?
DMACMD_DIR : 0));
esc->sc_active = 0;
return (0);
}
KASSERT(esc->sc_active != 0, ("%s: DMA wasn't active", __func__));
/* DMA has stopped. */
esc->sc_active = 0;
dmasize = esc->sc_dmasize;
if (dmasize == 0) {
/* A "Transfer Pad" operation completed. */
NCR_DMA(("%s: discarded %d bytes (tcl=%d, tcm=%d)\n",
__func__, READ_ESPREG(esc, NCR_TCL) |
(READ_ESPREG(esc, NCR_TCM) << 8),
READ_ESPREG(esc, NCR_TCL), READ_ESPREG(esc, NCR_TCM)));
return (0);
}
resid = 0;
/*
* If a transfer onto the SCSI bus gets interrupted by the device
* (e.g. for a SAVEPOINTER message), the data in the FIFO counts
* as residual since the ESP counter registers get decremented as
* bytes are clocked into the FIFO.
*/
if (datain == 0 &&
(resid = (READ_ESPREG(esc, NCR_FFLAG) & NCRFIFO_FF)) != 0)
NCR_DMA(("%s: empty esp FIFO of %d ", __func__, resid));
if ((sc->sc_espstat & NCRSTAT_TC) == 0) {
/*
* "Terminal count" is off, so read the residue
* out of the ESP counter registers.
*/
if (datain != 0) {
resid = READ_ESPREG(esc, NCR_FFLAG) & NCRFIFO_FF;
while (resid > 1)
resid =
READ_ESPREG(esc, NCR_FFLAG) & NCRFIFO_FF;
WRITE_DMAREG(esc, DMA_CMD, DMACMD_BLAST | DMACMD_DIR);
for (i = 0; i < 0x8000; i++) /* XXX 0x8000 ? */
if ((READ_DMAREG(esc, DMA_STAT) &
DMASTAT_BCMP) != 0)
break;
/* See the below comments... */
if (resid != 0)
p = *esc->sc_dmaaddr;
}
resid += READ_ESPREG(esc, NCR_TCL) |
(READ_ESPREG(esc, NCR_TCM) << 8) |
(READ_ESPREG(esc, NCR_TCH) << 16);
} else
while ((dmastat & DMASTAT_DONE) == 0)
dmastat = READ_DMAREG(esc, DMA_STAT);
WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | (datain != 0 ?
DMACMD_DIR : 0));
/* Sync the transfer buffer. */
bus_dmamap_sync(xferdmat, xferdmam, datain != 0 ?
BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
bus_dmamap_unload(xferdmat, xferdmam);
trans = dmasize - resid;
/*
* From the technical manual notes:
*
* "In some odd byte conditions, one residual byte will be left
* in the SCSI FIFO, and the FIFO flags will never count to 0.
* When this happens, the residual byte should be retrieved
* via PIO following completion of the BLAST operation."
*/
if (p != NULL) {
p += trans;
*p = READ_ESPREG(esc, NCR_FIFO);
trans++;
}
if (trans < 0) { /* transferred < 0 ? */
#if 0
/*
* This situation can happen in perfectly normal operation
* if the ESP is reselected while using DMA to select
* another target. As such, don't print the warning.
*/
device_printf(dev, "xfer (%d) > req (%d)\n", trans, dmasize);
#endif
trans = dmasize;
}
NCR_DMA(("%s: tcl=%d, tcm=%d, tch=%d; trans=%d, resid=%d\n", __func__,
READ_ESPREG(esc, NCR_TCL), READ_ESPREG(esc, NCR_TCM),
READ_ESPREG(esc, NCR_TCH), trans, resid));
*esc->sc_dmalen -= trans;
*esc->sc_dmaaddr = (char *)*esc->sc_dmaaddr + trans;
return (0);
}
static int
esp_pci_dma_setup(struct ncr53c9x_softc *sc, void **addr, size_t *len,
int datain, size_t *dmasize)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
int error;
WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | (datain != 0 ? DMACMD_DIR :
0));
*dmasize = esc->sc_dmasize = ulmin(*dmasize, MDL_SEG_SIZE);
esc->sc_dmaaddr = addr;
esc->sc_dmalen = len;
esc->sc_datain = datain;
/*
* There's no need to set up DMA for a "Transfer Pad" operation.
*/
if (*dmasize == 0)
return (0);
/* Set the transfer length. */
WRITE_DMAREG(esc, DMA_STC, *dmasize);
/*
* Load the transfer buffer and program the DMA address.
* Note that the NCR53C9x core can't handle EINPROGRESS so we set
* BUS_DMA_NOWAIT.
*/
error = bus_dmamap_load(esc->sc_xferdmat, esc->sc_xferdmam,
*esc->sc_dmaaddr, *dmasize, esp_pci_xfermap, sc, BUS_DMA_NOWAIT);
return (error);
}
static void
esp_pci_dma_go(struct ncr53c9x_softc *sc)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
int datain;
datain = esc->sc_datain;
/* No DMA transfer for a "Transfer Pad" operation */
if (esc->sc_dmasize == 0)
return;
/* Sync the transfer buffer. */
bus_dmamap_sync(esc->sc_xferdmat, esc->sc_xferdmam, datain != 0 ?
BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
/* Set the DMA engine to the IDLE state. */
/* XXX DMA Transfer Interrupt Enable bit is broken? */
WRITE_DMAREG(esc, DMA_CMD, DMACMD_IDLE | /* DMACMD_INTE | */
(datain != 0 ? DMACMD_DIR : 0));
/* Issue a DMA start command. */
WRITE_DMAREG(esc, DMA_CMD, DMACMD_START | /* DMACMD_INTE | */
(datain != 0 ? DMACMD_DIR : 0));
esc->sc_active = 1;
}
static void
esp_pci_dma_stop(struct ncr53c9x_softc *sc)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
/* DMA stop */
/* XXX what should we do here ? */
WRITE_DMAREG(esc, DMA_CMD,
DMACMD_ABORT | (esc->sc_datain != 0 ? DMACMD_DIR : 0));
bus_dmamap_unload(esc->sc_xferdmat, esc->sc_xferdmam);
esc->sc_active = 0;
}
static int
esp_pci_dma_isactive(struct ncr53c9x_softc *sc)
{
struct esp_pci_softc *esc = (struct esp_pci_softc *)sc;
/* XXX should we check esc->sc_active? */
if ((READ_DMAREG(esc, DMA_CMD) & DMACMD_CMD) != DMACMD_IDLE)
return (1);
return (0);
}