Date: Mon, 25 Aug 1997 21:19:19 -0700 From: Amancio Hasty <hasty@rah.star-gate.com> To: hackers@freebsd.org Subject: isa.c patch Message-ID: <199708260419.VAA00268@rah.star-gate.com>
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Here is a patch to alleviate the current problem with the dma interface
and the sound driver which uses auto dma.
The dma interface functionality remains however it now checks
to see if a dma is operating in auto dma mode and if so it bypasses
the busy flag check . I have modified the sound driver 3.5 to
adjust for this new behavior and tested it under FreeBSD 3.0 -current
Amancio
*** isa.c.orig Mon Aug 25 21:04:10 1997
--- isa.c Mon Aug 25 21:04:22 1997
***************
*** 570,575 ****
--- 570,576 ----
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;
#define VALID_DMA_MASK (7)
***************
*** 631,636 ****
--- 632,638 ----
return (EBUSY);
}
dma_inuse |= (1 << chan);
+ dma_auto_mode &= ~(1 << chan);
return (0);
}
***************
*** 662,667 ****
--- 664,670 ----
}
dma_inuse &= ~(1 << chan);
+ dma_auto_mode &= ~(1 << chan);
}
/*
***************
*** 736,741 ****
--- 739,750 ----
/* translate to physical */
phys = pmap_extract(pmap_kernel(), (vm_offset_t)addr);
+ if (flags & B_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
***************
*** 816,830 ****
printf("isa_dmadone: channel %d not acquired\n", chan);
#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)) == 0)
printf("isa_dmadone: channel %d not busy\n", chan);
! #endif
if (dma_bounced & (1 << chan)) {
/* copy bounce buffer on read */
--- 825,834 ----
printf("isa_dmadone: channel %d not acquired\n", chan);
#endif
! if (((dma_busy & (1 << chan)) == 0) &&
! (dma_auto_mode & (1 << chan)) == 0 )
printf("isa_dmadone: channel %d not busy\n", chan);
!
if (dma_bounced & (1 << chan)) {
/* copy bounce buffer on read */
***************
*** 913,924 ****
printf("isa_dmastatus: channel %d not active\n", chan);
return(-1);
}
! /* still busy? */
! if ((dma_busy & (1 << chan)) == 0) {
! return(0);
! }
!
if (chan < 4) { /* low DMA controller */
ffport = DMA1_FFC;
waport = DMA1_CHN(chan) + 1;
--- 917,929 ----
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;
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