/*-
* Copyright (c) 1996 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Adam Glass, David Jones, and Gordon W. Ross.
*
* 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.
*/
/*
* This file contains only the machine-dependent parts of the
* Sun3 SCSI driver. (Autoconfig stuff and DMA functions.)
* The machine-independent parts are in ncr5380sbc.c
*
* Supported hardware includes:
* Sun SCSI-3 on OBIO (Sun3/50,Sun3/60)
* Sun SCSI-3 on VME (Sun3/160,Sun3/260)
*
* Could be made to support the Sun3/E if someone wanted to.
*
* Note: Both supported variants of the Sun SCSI-3 adapter have
* some really unusual "features" for this driver to deal with,
* generally related to the DMA engine. The OBIO variant will
* ignore any attempt to write the FIFO count register while the
* SCSI bus is in DATA_IN or DATA_OUT phase. This is dealt with
* by setting the FIFO count early in COMMAND or MSG_IN phase.
*
* The VME variant has a bit to enable or disable the DMA engine,
* but that bit also gates the interrupt line from the NCR5380!
* Therefore, in order to get any interrupt from the 5380, (i.e.
* for reselect) one must clear the DMA engine transfer count and
* then enable DMA. This has the further complication that you
* CAN NOT touch the NCR5380 while the DMA enable bit is set, so
* we have to turn DMA back off before we even look at the 5380.
*
* What wonderfully whacky hardware this is!
*
* Credits, history:
*
* David Jones wrote the initial version of this module, which
* included support for the VME adapter only. (no reselection).
*
* Gordon Ross added support for the OBIO adapter, and re-worked
* both the VME and OBIO code to support disconnect/reselect.
* (Required figuring out the hardware "features" noted above.)
*
* The autoconfiguration boilerplate came from Adam Glass.
*/
if (csr & SI_CSR_DMA_CONFLICT) {
dma_error |= SI_CSR_DMA_CONFLICT;
printf("%s: DMA conflict\n", __func__);
}
if (csr & SI_CSR_DMA_BUS_ERR) {
dma_error |= SI_CSR_DMA_BUS_ERR;
printf("%s: DMA bus error\n", __func__);
}
if (dma_error) {
if (sc->ncr_sc.sc_state & NCR_DOINGDMA)
sc->ncr_sc.sc_state |= NCR_ABORTING;
/* Make sure we will call the main isr. */
csr |= SI_CSR_DMA_IP;
}
if (csr & (SI_CSR_SBC_IP | SI_CSR_DMA_IP)) {
claimed = ncr5380_intr(&sc->ncr_sc);
#ifdef DEBUG
if (!claimed) {
printf("%s: spurious from SBC\n", __func__);
if (si_debug & 4)
Debugger(); /* XXX */
}
#endif
/* Yes, we DID cause this interrupt. */
claimed = 1;
}
return claimed;
}
/*****************************************************************
* Common functions for DMA
****************************************************************/
/*
* Allocate a DMA handle and put it in sc->sc_dma. Prepare
* for DMA transfer. On the Sun3, this means mapping the buffer
* into DVMA space. dvma_mapin() flushes the cache for us.
*/
void
si_dma_alloc(struct ncr5380_softc *ncr_sc)
{
struct si_softc *sc = (struct si_softc *)ncr_sc;
struct sci_req *sr = ncr_sc->sc_current;
struct scsipi_xfer *xs = sr->sr_xs;
struct si_dma_handle *dh;
int i, xlen;
void *addr;
#ifdef DIAGNOSTIC
if (sr->sr_dma_hand != NULL)
panic("%s: already have DMA handle", __func__);
#endif
/* If the DMA start addr is misaligned then do PIO */
if (((vaddr_t)addr & 1) || (xlen & 1)) {
printf("%s: misaligned.\n", __func__);
return;
}
/* Make sure our caller checked sc_min_dma_len. */
if (xlen < MIN_DMA_LEN)
panic("%s: xlen=0x%x", __func__, xlen);
/*
* Never attempt single transfers of more than 63k, because
* our count register may be only 16 bits (an OBIO adapter).
* This should never happen since already bounded by minphys().
* XXX - Should just segment these...
*/
if (xlen > MAX_DMA_LEN) {
printf("%s: excessive xlen=0x%x\n", __func__, xlen);
Debugger();
ncr_sc->sc_datalen = xlen = MAX_DMA_LEN;
}
/* Find free DMA handle. Guaranteed to find one since we have
as many DMA handles as the driver has processes. */
for (i = 0; i < SCI_OPENINGS; i++) {
if ((sc->sc_dma[i].dh_flags & SIDH_BUSY) == 0)
goto found;
}
panic("si: no free DMA handles.");
found:
#if 0
/*
* Some machines might not need to remap B_PHYS buffers.
* The sun3 does not map B_PHYS buffers into DVMA space,
* (they are mapped into normal KV space) so on the sun3
* we must always remap to a DVMA address here. Re-map is
* cheap anyway, because it's done by segments, not pages.
*/
if (xs->bp && (xs->bp->b_flags & B_PHYS))
dh->dh_flags |= SIDH_PHYS;
#endif
/*
* Poll (spin-wait) for DMA completion.
* Called right after xx_dma_start(), and
* xx_dma_stop() will be called next.
* Same for either VME or OBIO.
*/
void
si_dma_poll(struct ncr5380_softc *ncr_sc)
{
struct si_softc *sc = (struct si_softc *)ncr_sc;
struct sci_req *sr = ncr_sc->sc_current;
volatile struct si_regs *si = sc->sc_regs;
int tmo;
/* Make sure DMA started successfully. */
if (ncr_sc->sc_state & NCR_ABORTING)
return;
/*
* XXX: The Sun driver waits for ~SI_CSR_DMA_ACTIVE here
* XXX: (on obio) or even worse (on vme) a 10mS. delay!
* XXX: I really doubt that is necessary...
*/
/* Wait for any "DMA complete" or error bits. */
tmo = POLL_TIMO;
for (;;) {
if (si->si_csr & CSR_MASK)
break;
if (--tmo <= 0) {
printf("si: DMA timeout (while polling)\n");
/* Indicate timeout as MI code would. */
sr->sr_flags |= SR_OVERDUE;
break;
}
delay(100);
}
NCR_TRACE("si_dma_poll: waited %d\n",
POLL_TIMO - tmo);
