Home | History | Annotate | Line # | Download | only in dev
si.c revision 1.61.2.1
      1 /*	$NetBSD: si.c,v 1.61.2.1 2008/05/18 12:32:54 yamt Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Adam Glass, David Jones, and Gordon W. Ross.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * This file contains only the machine-dependent parts of the
     34  * Sun3 SCSI driver.  (Autoconfig stuff and DMA functions.)
     35  * The machine-independent parts are in ncr5380sbc.c
     36  *
     37  * Supported hardware includes:
     38  * Sun SCSI-3 on OBIO (Sun3/50,Sun3/60)
     39  * Sun SCSI-3 on VME (Sun3/160,Sun3/260)
     40  *
     41  * Could be made to support the Sun3/E if someone wanted to.
     42  *
     43  * Note:  Both supported variants of the Sun SCSI-3 adapter have
     44  * some really unusual "features" for this driver to deal with,
     45  * generally related to the DMA engine.  The OBIO variant will
     46  * ignore any attempt to write the FIFO count register while the
     47  * SCSI bus is in DATA_IN or DATA_OUT phase.  This is dealt with
     48  * by setting the FIFO count early in COMMAND or MSG_IN phase.
     49  *
     50  * The VME variant has a bit to enable or disable the DMA engine,
     51  * but that bit also gates the interrupt line from the NCR5380!
     52  * Therefore, in order to get any interrupt from the 5380, (i.e.
     53  * for reselect) one must clear the DMA engine transfer count and
     54  * then enable DMA.  This has the further complication that you
     55  * CAN NOT touch the NCR5380 while the DMA enable bit is set, so
     56  * we have to turn DMA back off before we even look at the 5380.
     57  *
     58  * What wonderfully whacky hardware this is!
     59  *
     60  * Credits, history:
     61  *
     62  * David Jones wrote the initial version of this module, which
     63  * included support for the VME adapter only. (no reselection).
     64  *
     65  * Gordon Ross added support for the OBIO adapter, and re-worked
     66  * both the VME and OBIO code to support disconnect/reselect.
     67  * (Required figuring out the hardware "features" noted above.)
     68  *
     69  * The autoconfiguration boilerplate came from Adam Glass.
     70  */
     71 
     72 #include <sys/cdefs.h>
     73 __KERNEL_RCSID(0, "$NetBSD: si.c,v 1.61.2.1 2008/05/18 12:32:54 yamt Exp $");
     74 
     75 #include <sys/param.h>
     76 #include <sys/systm.h>
     77 #include <sys/errno.h>
     78 #include <sys/kernel.h>
     79 #include <sys/malloc.h>
     80 #include <sys/device.h>
     81 #include <sys/buf.h>
     82 #include <sys/proc.h>
     83 #include <sys/user.h>
     84 
     85 #include <dev/scsipi/scsi_all.h>
     86 #include <dev/scsipi/scsipi_all.h>
     87 #include <dev/scsipi/scsipi_debug.h>
     88 #include <dev/scsipi/scsiconf.h>
     89 
     90 #include <machine/autoconf.h>
     91 #include <machine/bus.h>
     92 #include <machine/dvma.h>
     93 
     94 /* #define DEBUG XXX */
     95 
     96 #include <dev/ic/ncr5380reg.h>
     97 #include <dev/ic/ncr5380var.h>
     98 
     99 #include "sireg.h"
    100 #include "sivar.h"
    101 
    102 /*
    103  * Transfers smaller than this are done using PIO
    104  * (on assumption they're not worth DMA overhead)
    105  */
    106 #define	MIN_DMA_LEN 128
    107 
    108 int si_debug = 0;
    109 #ifdef	DEBUG
    110 #endif
    111 
    112 /* How long to wait for DMA before declaring an error. */
    113 int si_dma_intr_timo = 500;	/* ticks (sec. X 100) */
    114 
    115 static void	si_minphys(struct buf *);
    116 
    117 /*
    118  * New-style autoconfig attachment. The cfattach
    119  * structures are in si_obio.c and si_vme.c
    120  */
    121 
    122 void
    123 si_attach(struct si_softc *sc)
    124 {
    125 	struct ncr5380_softc *ncr_sc = &sc->ncr_sc;
    126 	volatile struct si_regs *regs = sc->sc_regs;
    127 	int i;
    128 
    129 	/*
    130 	 * Support the "options" (config file flags).
    131 	 * Disconnect/reselect is a per-target mask.
    132 	 * Interrupts and DMA are per-controller.
    133 	 */
    134 	ncr_sc->sc_no_disconnect =
    135 	    (sc->sc_options & SI_NO_DISCONNECT);
    136 	ncr_sc->sc_parity_disable =
    137 	    (sc->sc_options & SI_NO_PARITY_CHK) >> 8;
    138 	if (sc->sc_options & SI_FORCE_POLLING)
    139 		ncr_sc->sc_flags |= NCR5380_FORCE_POLLING;
    140 
    141 #if 1	/* XXX - Temporary */
    142 	/* XXX - In case we think DMA is completely broken... */
    143 	if (sc->sc_options & SI_DISABLE_DMA) {
    144 		/* Override this function pointer. */
    145 		ncr_sc->sc_dma_alloc = NULL;
    146 	}
    147 #endif
    148 	ncr_sc->sc_min_dma_len = MIN_DMA_LEN;
    149 
    150 	/*
    151 	 * Initialize fields used by the MI code
    152 	 */
    153 	ncr_sc->sci_r0 = &regs->sci.sci_r0;
    154 	ncr_sc->sci_r1 = &regs->sci.sci_r1;
    155 	ncr_sc->sci_r2 = &regs->sci.sci_r2;
    156 	ncr_sc->sci_r3 = &regs->sci.sci_r3;
    157 	ncr_sc->sci_r4 = &regs->sci.sci_r4;
    158 	ncr_sc->sci_r5 = &regs->sci.sci_r5;
    159 	ncr_sc->sci_r6 = &regs->sci.sci_r6;
    160 	ncr_sc->sci_r7 = &regs->sci.sci_r7;
    161 
    162 	ncr_sc->sc_rev = NCR_VARIANT_NCR5380;
    163 
    164 	/*
    165 	 * Allocate DMA handles.
    166 	 */
    167 	i = SCI_OPENINGS * sizeof(struct si_dma_handle);
    168 	sc->sc_dma = (struct si_dma_handle *)
    169 		malloc(i, M_DEVBUF, M_WAITOK);
    170 	if (sc->sc_dma == NULL)
    171 		panic("si: dvma_malloc failed");
    172 	for (i = 0; i < SCI_OPENINGS; i++)
    173 		sc->sc_dma[i].dh_flags = 0;
    174 
    175 	ncr_sc->sc_channel.chan_id = 7;
    176 	ncr_sc->sc_adapter.adapt_minphys = si_minphys;
    177 
    178 	/*
    179 	 *  Initialize si board itself.
    180 	 */
    181 	ncr5380_attach(ncr_sc);
    182 }
    183 
    184 static void
    185 si_minphys(struct buf *bp)
    186 {
    187 
    188 	if (bp->b_bcount > MAX_DMA_LEN) {
    189 #ifdef	DEBUG
    190 		if (si_debug) {
    191 			printf("%s len = 0x%x.\n", __func__, bp->b_bcount);
    192 			Debugger();
    193 		}
    194 #endif
    195 		bp->b_bcount = MAX_DMA_LEN;
    196 	}
    197 	minphys(bp);
    198 }
    199 
    200 
    201 #define CSR_WANT (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
    202 	SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR )
    203 
    204 int
    205 si_intr(void *arg)
    206 {
    207 	struct si_softc *sc = arg;
    208 	volatile struct si_regs *si = sc->sc_regs;
    209 	int dma_error, claimed;
    210 	u_short csr;
    211 
    212 	claimed = 0;
    213 	dma_error = 0;
    214 
    215 	/* SBC interrupt? DMA interrupt? */
    216 	csr = si->si_csr;
    217 	NCR_TRACE("si_intr: csr=0x%x\n", csr);
    218 
    219 	if (csr & SI_CSR_DMA_CONFLICT) {
    220 		dma_error |= SI_CSR_DMA_CONFLICT;
    221 		printf("%s: DMA conflict\n", __func__);
    222 	}
    223 	if (csr & SI_CSR_DMA_BUS_ERR) {
    224 		dma_error |= SI_CSR_DMA_BUS_ERR;
    225 		printf("%s: DMA bus error\n", __func__);
    226 	}
    227 	if (dma_error) {
    228 		if (sc->ncr_sc.sc_state & NCR_DOINGDMA)
    229 			sc->ncr_sc.sc_state |= NCR_ABORTING;
    230 		/* Make sure we will call the main isr. */
    231 		csr |= SI_CSR_DMA_IP;
    232 	}
    233 
    234 	if (csr & (SI_CSR_SBC_IP | SI_CSR_DMA_IP)) {
    235 		claimed = ncr5380_intr(&sc->ncr_sc);
    236 #ifdef	DEBUG
    237 		if (!claimed) {
    238 			printf("%s: spurious from SBC\n", __func__);
    239 			if (si_debug & 4)
    240 				Debugger();	/* XXX */
    241 		}
    242 #endif
    243 		/* Yes, we DID cause this interrupt. */
    244 		claimed = 1;
    245 	}
    246 
    247 	return claimed;
    248 }
    249 
    250 
    251 /*****************************************************************
    252  * Common functions for DMA
    253  ****************************************************************/
    254 
    255 /*
    256  * Allocate a DMA handle and put it in sc->sc_dma.  Prepare
    257  * for DMA transfer.  On the Sun3, this means mapping the buffer
    258  * into DVMA space.  dvma_mapin() flushes the cache for us.
    259  */
    260 void
    261 si_dma_alloc(struct ncr5380_softc *ncr_sc)
    262 {
    263 	struct si_softc *sc = (struct si_softc *)ncr_sc;
    264 	struct sci_req *sr = ncr_sc->sc_current;
    265 	struct scsipi_xfer *xs = sr->sr_xs;
    266 	struct si_dma_handle *dh;
    267 	int i, xlen;
    268 	void *addr;
    269 
    270 #ifdef	DIAGNOSTIC
    271 	if (sr->sr_dma_hand != NULL)
    272 		panic("%s: already have DMA handle", __func__);
    273 #endif
    274 
    275 	addr = ncr_sc->sc_dataptr;
    276 	xlen = ncr_sc->sc_datalen;
    277 
    278 	/* If the DMA start addr is misaligned then do PIO */
    279 	if (((vaddr_t)addr & 1) || (xlen & 1)) {
    280 		printf("%s: misaligned.\n", __func__);
    281 		return;
    282 	}
    283 
    284 	/* Make sure our caller checked sc_min_dma_len. */
    285 	if (xlen < MIN_DMA_LEN)
    286 		panic("%s: xlen=0x%x", __func__, xlen);
    287 
    288 	/*
    289 	 * Never attempt single transfers of more than 63k, because
    290 	 * our count register may be only 16 bits (an OBIO adapter).
    291 	 * This should never happen since already bounded by minphys().
    292 	 * XXX - Should just segment these...
    293 	 */
    294 	if (xlen > MAX_DMA_LEN) {
    295 		printf("%s: excessive xlen=0x%x\n", __func__, xlen);
    296 		Debugger();
    297 		ncr_sc->sc_datalen = xlen = MAX_DMA_LEN;
    298 	}
    299 
    300 	/* Find free DMA handle.  Guaranteed to find one since we have
    301 	   as many DMA handles as the driver has processes. */
    302 	for (i = 0; i < SCI_OPENINGS; i++) {
    303 		if ((sc->sc_dma[i].dh_flags & SIDH_BUSY) == 0)
    304 			goto found;
    305 	}
    306 	panic("si: no free DMA handles.");
    307 found:
    308 
    309 	dh = &sc->sc_dma[i];
    310 	dh->dh_flags = SIDH_BUSY;
    311 
    312 	if (bus_dmamap_load(sc->sc_dmat, sc->sc_dmap, addr, xlen, NULL,
    313 	    BUS_DMA_NOWAIT) != 0)
    314 		panic("%s: can't load dmamap", device_xname(ncr_sc->sc_dev));
    315 	dh->dh_dmaaddr = sc->sc_dmap->dm_segs[0].ds_addr;
    316 	dh->dh_dmalen  = xlen;
    317 
    318 	/* Copy the "write" flag for convenience. */
    319 	if (xs->xs_control & XS_CTL_DATA_OUT)
    320 		dh->dh_flags |= SIDH_OUT;
    321 
    322 	bus_dmamap_sync(sc->sc_dmat, sc->sc_dmap, 0, dh->dh_dmalen,
    323 	    (dh->dh_flags & SIDH_OUT) == 0 ?
    324 	    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
    325 
    326 #if 0
    327 	/*
    328 	 * Some machines might not need to remap B_PHYS buffers.
    329 	 * The sun3 does not map B_PHYS buffers into DVMA space,
    330 	 * (they are mapped into normal KV space) so on the sun3
    331 	 * we must always remap to a DVMA address here. Re-map is
    332 	 * cheap anyway, because it's done by segments, not pages.
    333 	 */
    334 	if (xs->bp && (xs->bp->b_flags & B_PHYS))
    335 		dh->dh_flags |= SIDH_PHYS;
    336 #endif
    337 
    338 	/* success */
    339 	sr->sr_dma_hand = dh;
    340 
    341 	return;
    342 }
    343 
    344 
    345 void
    346 si_dma_free(struct ncr5380_softc *ncr_sc)
    347 {
    348 	struct si_softc *sc = (struct si_softc *)ncr_sc;
    349 	struct sci_req *sr = ncr_sc->sc_current;
    350 	struct si_dma_handle *dh = sr->sr_dma_hand;
    351 
    352 #ifdef	DIAGNOSTIC
    353 	if (dh == NULL)
    354 		panic("%s: no DMA handle", __func__);
    355 #endif
    356 
    357 	if (ncr_sc->sc_state & NCR_DOINGDMA)
    358 		panic("%s: free while in progress", __func__);
    359 
    360 	if (dh->dh_flags & SIDH_BUSY) {
    361 		bus_dmamap_sync(sc->sc_dmat, sc->sc_dmap, 0, dh->dh_dmalen,
    362 		    (dh->dh_flags & SIDH_OUT) == 0 ?
    363 		    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
    364 		bus_dmamap_unload(sc->sc_dmat, sc->sc_dmap);
    365 		dh->dh_dmaaddr = 0;
    366 		dh->dh_flags = 0;
    367 	}
    368 	sr->sr_dma_hand = NULL;
    369 }
    370 
    371 
    372 #define	CSR_MASK (SI_CSR_SBC_IP | SI_CSR_DMA_IP | \
    373 		SI_CSR_DMA_CONFLICT | SI_CSR_DMA_BUS_ERR)
    374 #define	POLL_TIMO	50000	/* X100 = 5 sec. */
    375 
    376 /*
    377  * Poll (spin-wait) for DMA completion.
    378  * Called right after xx_dma_start(), and
    379  * xx_dma_stop() will be called next.
    380  * Same for either VME or OBIO.
    381  */
    382 void
    383 si_dma_poll(struct ncr5380_softc *ncr_sc)
    384 {
    385 	struct si_softc *sc = (struct si_softc *)ncr_sc;
    386 	struct sci_req *sr = ncr_sc->sc_current;
    387 	volatile struct si_regs *si = sc->sc_regs;
    388 	int tmo;
    389 
    390 	/* Make sure DMA started successfully. */
    391 	if (ncr_sc->sc_state & NCR_ABORTING)
    392 		return;
    393 
    394 	/*
    395 	 * XXX: The Sun driver waits for ~SI_CSR_DMA_ACTIVE here
    396 	 * XXX: (on obio) or even worse (on vme) a 10mS. delay!
    397 	 * XXX: I really doubt that is necessary...
    398 	 */
    399 
    400 	/* Wait for any "DMA complete" or error bits. */
    401 	tmo = POLL_TIMO;
    402 	for (;;) {
    403 		if (si->si_csr & CSR_MASK)
    404 			break;
    405 		if (--tmo <= 0) {
    406 			printf("si: DMA timeout (while polling)\n");
    407 			/* Indicate timeout as MI code would. */
    408 			sr->sr_flags |= SR_OVERDUE;
    409 			break;
    410 		}
    411 		delay(100);
    412 	}
    413 	NCR_TRACE("si_dma_poll: waited %d\n",
    414 			  POLL_TIMO - tmo);
    415 
    416 #ifdef	DEBUG
    417 	if (si_debug & 2) {
    418 		printf("%s: done, csr=0x%x\n", __func__, si->si_csr);
    419 	}
    420 #endif
    421 }
    422