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NetBSD/sys/arch/next68k/dev/nextdma.c

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/* $NetBSD: nextdma.c,v 1.4 1998/07/21 06:17:35 dbj Exp $ */
/*
* Copyright (c) 1998 Darrin B. Jewell
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Darrin B. Jewell
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/syslog.h>
#include <sys/socket.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <machine/autoconf.h>
#include <machine/cpu.h>
#include <machine/intr.h>
#include <next68k/next68k/isr.h>
#define _GENERIC_BUS_DMA_PRIVATE
#include <machine/bus.h>
#include "nextdmareg.h"
#include "nextdmavar.h"
#if 0
#define ND_DEBUG
#endif
#if defined(ND_DEBUG)
#define DPRINTF(x) printf x;
#else
#define DPRINTF(x)
#endif
/* @@@ for debugging */
struct nextdma_config *debugernd;
struct nextdma_config *debugexnd;
int nextdma_intr __P((void *));
void next_dmamap_sync __P((bus_dma_tag_t, bus_dmamap_t, bus_addr_t,
bus_size_t, int));
int next_dma_continue __P((struct nextdma_config *));
void next_dma_rotate __P((struct nextdma_config *));
void next_dma_setup_cont_regs __P((struct nextdma_config *));
void next_dma_setup_curr_regs __P((struct nextdma_config *));
void next_dma_print __P((struct nextdma_config *));
void
nextdma_config(nd)
struct nextdma_config *nd;
{
/* Initialize the dma_tag. As a hack, we currently
* put the dma tag in the structure itself. It shouldn't be there.
*/
{
bus_dma_tag_t t;
t = &nd->_nd_dmat;
t->_cookie = nd;
t->_get_tag = NULL; /* lose */
t->_dmamap_create = _bus_dmamap_create;
t->_dmamap_destroy = _bus_dmamap_destroy;
t->_dmamap_load = _bus_dmamap_load_direct;
t->_dmamap_load_mbuf = _bus_dmamap_load_mbuf_direct;
t->_dmamap_load_uio = _bus_dmamap_load_uio_direct;
t->_dmamap_load_raw = _bus_dmamap_load_raw_direct;
t->_dmamap_unload = _bus_dmamap_unload;
t->_dmamap_sync = next_dmamap_sync;
t->_dmamem_alloc = _bus_dmamem_alloc;
t->_dmamem_free = _bus_dmamem_free;
t->_dmamem_map = _bus_dmamem_map;
t->_dmamem_unmap = _bus_dmamem_unmap;
t->_dmamem_mmap = _bus_dmamem_mmap;
nd->nd_dmat = t;
}
/* @@@ for debugging */
if (nd->nd_intr == NEXT_I_ENETR_DMA) {
debugernd = nd;
}
if (nd->nd_intr == NEXT_I_ENETX_DMA) {
debugexnd = nd;
}
nextdma_init(nd);
isrlink_autovec(nextdma_intr, nd, NEXT_I_IPL(nd->nd_intr), 10);
INTR_ENABLE(nd->nd_intr);
}
void
nextdma_init(nd)
struct nextdma_config *nd;
{
DPRINTF(("DMA init ipl (%ld) intr(0x%b)\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS));
/* @@@ should probably check and free these maps */
nd->_nd_map = NULL;
nd->_nd_idx = 0;
nd->_nd_map_cont = NULL;
nd->_nd_idx_cont = 0;
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR, 0);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_INITBUF | DMACSR_CLRCOMPLETE | DMACSR_RESET);
next_dma_setup_curr_regs(nd);
next_dma_setup_cont_regs(nd);
#if 0 && defined(DIAGNOSTIC)
/* Today, my computer (mourning) appears to fail this test.
* yesterday, another NeXT (milo) didn't have this problem
* Darrin B. Jewell <jewell@mit.edu> Mon May 25 07:53:05 1998
*/
{
u_long state;
state = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_CSR);
state = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_CSR);
state &= (DMACSR_BUSEXC | DMACSR_COMPLETE |
DMACSR_SUPDATE | DMACSR_ENABLE);
if (state) {
next_dma_print(nd);
panic("DMA did not reset\n");
}
}
#endif
}
void
nextdma_reset(nd)
struct nextdma_config *nd;
{
int s;
s = spldma(); /* @@@ should this be splimp()? */
nextdma_init(nd);
splx(s);
}
/****************************************************************/
/* If the next had multiple busses, this should probably
* go elsewhere, but it is here anyway */
void
next_dmamap_sync(t, map, offset, len, ops)
bus_dma_tag_t t;
bus_dmamap_t map;
bus_addr_t offset;
bus_size_t len;
int ops;
{
/* flush/purge the cache.
* assumes pointers are aligned
* @@@ should probably be fixed to use offset and len args.
* should also optimize this to work on pages for larger regions?
*/
if (ops & BUS_DMASYNC_PREWRITE) {
int i;
for(i=0;i<map->dm_nsegs;i++) {
bus_addr_t p = map->dm_segs[i].ds_addr;
bus_addr_t e = p+map->dm_segs[i].ds_len;
while(p<e) {
DCFL(p); /* flush */
p += 16; /* cache line length */
}
}
}
if (ops & BUS_DMASYNC_POSTREAD) {
int i;
for(i=0;i<map->dm_nsegs;i++) {
bus_addr_t p = map->dm_segs[i].ds_addr;
bus_addr_t e = p+map->dm_segs[i].ds_len;
while(p<e) {
DCPL(p); /* purge */
p += 16; /* cache line length */
}
}
}
}
/****************************************************************/
/* Call the completed and continue callbacks to try to fill
* in the dma continue buffers.
*/
void
next_dma_rotate(nd)
struct nextdma_config *nd;
{
DPRINTF(("DMA next_dma_rotate()\n"));
/* If we've reached the end of the current map, then inform
* that we've completed that map.
*/
if (nd->_nd_map && ((nd->_nd_idx+1) == nd->_nd_map->dm_nsegs)) {
if (nd->nd_completed_cb)
(*nd->nd_completed_cb)(nd->_nd_map, nd->nd_cb_arg);
}
/* Rotate the continue map into the current map */
nd->_nd_map = nd->_nd_map_cont;
nd->_nd_idx = nd->_nd_idx_cont;
if ((!nd->_nd_map_cont) ||
((nd->_nd_map_cont) &&
(++nd->_nd_idx_cont >= nd->_nd_map_cont->dm_nsegs))) {
if (nd->nd_continue_cb) {
nd->_nd_map_cont = (*nd->nd_continue_cb)(nd->nd_cb_arg);
} else {
nd->_nd_map_cont = 0;
}
nd->_nd_idx_cont = 0;
}
}
void
next_dma_setup_cont_regs(nd)
struct nextdma_config *nd;
{
DPRINTF(("DMA next_dma_setup_regs()\n"));
if (nd->_nd_map_cont) {
if (nd->nd_intr == NEXT_I_ENETX_DMA) {
/* Ethernet transmit needs secret magic */
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_START,
nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_addr);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_STOP,
((nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_addr +
nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_len)
+ 0x0) | 0x80000000);
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_START,
nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_addr);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_STOP,
nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_addr +
nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_len);
}
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_START,0);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_STOP, 0);
}
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_START,
bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_START));
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_STOP,
bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_STOP));
}
void
next_dma_setup_curr_regs(nd)
struct nextdma_config *nd;
{
DPRINTF(("DMA next_dma_setup_curr_regs()\n"));
if (nd->nd_intr == NEXT_I_ENETX_DMA) {
/* Ethernet transmit needs secret magic */
if (nd->_nd_map) {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_NEXT_INITBUF,
nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT,
((nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr +
nd->_nd_map->dm_segs[nd->_nd_idx].ds_len)
+ 0x0) | 0x80000000);
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_NEXT_INITBUF,0);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT, 0);
}
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_NEXT,
bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_NEXT_INITBUF));
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_LIMIT,
bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT));
} else {
if (nd->_nd_map) {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_NEXT,
nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT,
nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr +
nd->_nd_map->dm_segs[nd->_nd_idx].ds_len);
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_NEXT,0);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT, 0);
}
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_NEXT,
bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_NEXT));
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_LIMIT,
bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT));
}
}
/* This routine is used for debugging */
void
next_dma_print(nd)
struct nextdma_config *nd;
{
u_long dd_csr;
u_long dd_next;
u_long dd_next_initbuf;
u_long dd_limit;
u_long dd_start;
u_long dd_stop;
u_long dd_saved_next;
u_long dd_saved_limit;
u_long dd_saved_start;
u_long dd_saved_stop;
/* Read all of the registers before we print anything out,
* in case something changes
*/
dd_csr = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_CSR);
dd_next = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_NEXT);
dd_next_initbuf = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_NEXT_INITBUF);
dd_limit = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_LIMIT);
dd_start = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_START);
dd_stop = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_STOP);
dd_saved_next = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_NEXT);
dd_saved_limit = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_LIMIT);
dd_saved_start = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_START);
dd_saved_stop = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_STOP);
if (nd->_nd_map) {
printf("NDMAP: nd->_nd_map->dm_segs[%d].ds_addr = 0x%08lx\n",
nd->_nd_idx,nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr);
printf("NDMAP: nd->_nd_map->dm_segs[%d].ds_len = %d\n",
nd->_nd_idx,nd->_nd_map->dm_segs[nd->_nd_idx].ds_len);
} else {
printf("NDMAP: nd->_nd_map = NULL\n");
}
if (nd->_nd_map_cont) {
printf("NDMAP: nd->_nd_map_cont->dm_segs[%d].ds_addr = 0x%08lx\n",
nd->_nd_idx_cont,nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_addr);
printf("NDMAP: nd->_nd_map_cont->dm_segs[%d].ds_len = %d\n",
nd->_nd_idx_cont,nd->_nd_map_cont->dm_segs[nd->_nd_idx_cont].ds_len);
} else {
printf("NDMAP: nd->_nd_map_cont = NULL\n");
}
printf("NDMAP: dd->dd_csr = 0x%b\n", dd_csr, DMACSR_BITS);
printf("NDMAP: dd->dd_saved_next = 0x%08x\n", dd_saved_next);
printf("NDMAP: dd->dd_saved_limit = 0x%08x\n", dd_saved_limit);
printf("NDMAP: dd->dd_saved_start = 0x%08x\n", dd_saved_start);
printf("NDMAP: dd->dd_saved_stop = 0x%08x\n", dd_saved_stop);
printf("NDMAP: dd->dd_next = 0x%08x\n", dd_next);
printf("NDMAP: dd->dd_next_initbuf = 0x%08x\n", dd_next_initbuf);
printf("NDMAP: dd->dd_limit = 0x%08x\n", dd_limit);
printf("NDMAP: dd->dd_start = 0x%08x\n", dd_start);
printf("NDMAP: dd->dd_stop = 0x%08x\n", dd_stop);
printf("NDMAP: interrupt ipl (%ld) intr(0x%b)\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS);
}
/****************************************************************/
int
nextdma_intr(arg)
void *arg;
{
struct nextdma_config *nd = arg;
/* @@@ This is bogus, we can't be certain of arg's type
* unless the interrupt is for us
*/
if (!INTR_OCCURRED(nd->nd_intr)) return 0;
/* Handle dma interrupts */
#ifdef DIAGNOSTIC
if (nd->nd_intr == NEXT_I_ENETR_DMA) {
if (debugernd != nd) {
panic("DMA incorrect handling of rx nd->nd_intr");
}
}
if (nd->nd_intr == NEXT_I_ENETX_DMA) {
if (debugexnd != nd) {
panic("DMA incorrect handling of tx nd->nd_intr");
}
}
#endif
DPRINTF(("DMA interrupt ipl (%ld) intr(0x%b)\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS));
{
int state = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_CSR);
state &= (DMACSR_BUSEXC | DMACSR_COMPLETE |
DMACSR_SUPDATE | DMACSR_ENABLE);
if (state & DMACSR_BUSEXC) {
#if 0 /* This bit seems to get set periodically and I don't know why */
next_dma_print(nd);
panic("Bus exception in DMA ipl (%ld) intr(0x%b)\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS);
#endif
}
#ifdef DIAGNOSTIC
if (!(state & DMACSR_COMPLETE)) {
next_dma_print(nd);
#if 0 /* This bit doesn't seem to get set every once in a while,
* and I don't know why. Let's try treating it as a spurious
* interrupt. ie. report it and ignore the interrupt.
*/
printf("DEBUG: state = 0x%b\n", state,DMACSR_BITS);
panic("DMA ipl (%ld) intr(0x%b), DMACSR_COMPLETE not set in intr\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS);
#else
printf("DMA ipl (%ld) intr(0x%b), DMACSR_COMPLETE not set in intr\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS);
return(1);
#endif
}
#endif
/* Set the length of the segment to match actual length.
* @@@ is it okay to resize dma segments here?
* i should probably ask jason about this.
*/
if (nd->_nd_map) {
bus_addr_t next;
bus_addr_t limit;
#if 0
if (state & DMACSR_ENABLE) {
next = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_NEXT);
} else {
next = nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr;
}
#else
next = nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr;
#endif
limit = bus_space_read_4(nd->nd_bst, nd->nd_bsh, DD_SAVED_LIMIT);
if (nd->nd_intr == NEXT_I_ENETX_DMA) {
limit &= ~0x80000000;
}
#ifdef DIAGNOSTIC
if (next != nd->_nd_map->dm_segs[nd->_nd_idx].ds_addr) {
next_dma_print(nd);
printf("DEBUG: state = 0x%b\n", state,DMACSR_BITS);
panic("DMA ipl (%ld) intr(0x%b), unexpected completed address\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS);
}
#endif
/* @@@ I observed a case where DMACSR_ENABLE wasn't set and
* DD_SAVED_LIMIT didn't contain the expected limit value. This
* should be tested, fixed, and removed. */
if (((limit-next) > nd->_nd_map->dm_segs[nd->_nd_idx].ds_len)
|| (limit-next < 0)) {
#if 0
next_dma_print(nd);
printf("DEBUG: state = 0x%b\n", state,DMACSR_BITS);
panic("DMA packlen: next = 0x%08x limit = 0x%08x\n",next,limit);
#else
DPRINTF(("DMA packlen: next = 0x%08x limit = 0x%08x",next,limit));
#endif
} else {
nd->_nd_map->dm_segs[nd->_nd_idx].ds_len = limit - next;
}
}
if ((state & DMACSR_ENABLE) == 0) {
/* Non chaining interrupts shutdown immediately */
if (!nd->nd_chaining_flag) {
nd->_nd_map = nd->_nd_map_cont;
nd->_nd_idx = nd->_nd_idx_cont;
nd->_nd_map_cont = 0;
nd->_nd_idx_cont = 0;
}
/* Call the completed callback for the last packet */
if (nd->_nd_map && ((nd->_nd_idx+1) == nd->_nd_map->dm_nsegs)) {
if (nd->nd_completed_cb)
(*nd->nd_completed_cb)(nd->_nd_map, nd->nd_cb_arg);
}
nd->_nd_map = 0;
nd->_nd_idx = 0;
if (nd->_nd_map_cont) {
DPRINTF(("DMA ipl (%ld) intr(0x%b), restarting\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS));
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_SETSUPDATE | DMACSR_SETENABLE);
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_CLRCOMPLETE | DMACSR_RESET);
DPRINTF(("DMA: enable not set w/o continue map, shutting down dma\n"));
if (nd->nd_shutdown_cb) (*nd->nd_shutdown_cb)(nd->nd_cb_arg);
}
} else {
next_dma_rotate(nd);
next_dma_setup_cont_regs(nd);
if (nd->_nd_map_cont) {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_SETSUPDATE | DMACSR_CLRCOMPLETE);
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_CLRCOMPLETE);
}
}
}
DPRINTF(("DMA exiting interrupt ipl (%ld) intr(0x%b)\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS));
return(1);
}
/*
* Check to see if dma has finished for a channel */
int
nextdma_finished(nd)
struct nextdma_config *nd;
{
int r;
int s;
s = spldma(); /* @@@ should this be splimp()? */
r = (nd->_nd_map == NULL) && (nd->_nd_map_cont == NULL);
splx(s);
return(r);
}
void
nextdma_start(nd, dmadir)
struct nextdma_config *nd;
u_long dmadir; /* DMACSR_READ or DMACSR_WRITE */
{
#ifdef DIAGNOSTIC
if (!nextdma_finished(nd)) {
panic("DMA trying to start before previous finished on intr(0x%b)\n",
NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS);
}
#endif
DPRINTF(("DMA start (%ld) intr(0x%b)\n",
NEXT_I_IPL(nd->nd_intr), NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS));
#ifdef DIAGNOSTIC
if (nd->_nd_map) {
next_dma_print(nd);
panic("DMA: nextdma_start() with non null map\n");
}
if (nd->_nd_map_cont) {
next_dma_print(nd);
panic("DMA: nextdma_start() with non null continue map\n");
}
#endif
next_dma_rotate(nd);
#ifdef DIAGNOSTIC
if (!nd->_nd_map_cont) {
panic("No map available in nextdma_start()");
}
if (!DMA_BEGINALIGNED(nd->_nd_map_cont->dm_segs[nd->_nd_idx].ds_addr)) {
panic("unaligned begin dma at start\n");
}
if (!DMA_ENDALIGNED(nd->_nd_map_cont->dm_segs[nd->_nd_idx].ds_addr +
nd->_nd_map_cont->dm_segs[nd->_nd_idx].ds_len)) {
panic("unaligned end dma at start\n");
}
#endif
DPRINTF(("DMA initiating DMA %s of %d segments on intr(0x%b)\n",
(dmadir == DMACSR_READ ? "read" : "write"), nd->_nd_map_cont->dm_nsegs,
NEXT_I_BIT(nd->nd_intr),NEXT_INTR_BITS));
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR, 0);
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_INITBUF | DMACSR_RESET | dmadir);
next_dma_setup_cont_regs(nd);
/* When starting DMA, we must put the continue map
* into the current register. We reset the nd->_nd_map
* pointer here to avoid duplicated completed callbacks
* for the first buffer.
*/
nd->_nd_map = nd->_nd_map_cont;
nd->_nd_idx = nd->_nd_idx_cont;
next_dma_setup_curr_regs(nd);
nd->_nd_map = 0;
nd->_nd_idx = 0;
#if (defined(ND_DEBUG))
next_dma_print(nd);
#endif
if (nd->nd_chaining_flag) {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_SETSUPDATE | DMACSR_SETENABLE);
} else {
bus_space_write_4(nd->nd_bst, nd->nd_bsh, DD_CSR,
DMACSR_SETENABLE);
}
}
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