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authorBen Dooks <ben-linux@fluff.org>2006-08-18 10:32:10 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2006-08-18 10:32:10 -0400
commitf57e1abd1bb297994c7398478b4c37e628095243 (patch)
treef25447fd37bf0b56c5aa8b197570ac802d8ac904 /arch/arm
parenta0c5a64552e3c57d7f9eb593c6ce21a285ac86b4 (diff)
[ARM] 3753/1: S3C24XX: DMA fixes
Patch from Ben Dooks A number of small issues with the S3C24XX DMA have cropped up, which this patch fixes. These are: - check wether we can load another buff in start - update state handling in s3c2410_dma_lastxfer - only reload in irq if channel is not idle - more informative timeout errors (add source) - do not call request_irq() with irqs locked - added waitforstop function The patch also adds a S3C2410_DMAOP_STARTED for the occasions when the driver wants to ensure that the DMA system load state is resynced after loading. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/mach-s3c2410/dma.c163
1 files changed, 144 insertions, 19 deletions
diff --git a/arch/arm/mach-s3c2410/dma.c b/arch/arm/mach-s3c2410/dma.c
index 094cc52745c5..25855452fe8c 100644
--- a/arch/arm/mach-s3c2410/dma.c
+++ b/arch/arm/mach-s3c2410/dma.c
@@ -112,7 +112,7 @@ dmadbg_capture(s3c2410_dma_chan_t *chan, struct s3c2410_dma_regstate *regs)
112} 112}
113 113
114static void 114static void
115dmadbg_showregs(const char *fname, int line, s3c2410_dma_chan_t *chan, 115dmadbg_dumpregs(const char *fname, int line, s3c2410_dma_chan_t *chan,
116 struct s3c2410_dma_regstate *regs) 116 struct s3c2410_dma_regstate *regs)
117{ 117{
118 printk(KERN_DEBUG "dma%d: %s:%d: DCSRC=%08lx, DISRC=%08lx, DSTAT=%08lx DMT=%02lx, DCON=%08lx\n", 118 printk(KERN_DEBUG "dma%d: %s:%d: DCSRC=%08lx, DISRC=%08lx, DSTAT=%08lx DMT=%02lx, DCON=%08lx\n",
@@ -132,7 +132,16 @@ dmadbg_showchan(const char *fname, int line, s3c2410_dma_chan_t *chan)
132 chan->number, fname, line, chan->load_state, 132 chan->number, fname, line, chan->load_state,
133 chan->curr, chan->next, chan->end); 133 chan->curr, chan->next, chan->end);
134 134
135 dmadbg_showregs(fname, line, chan, &state); 135 dmadbg_dumpregs(fname, line, chan, &state);
136}
137
138static void
139dmadbg_showregs(const char *fname, int line, s3c2410_dma_chan_t *chan)
140{
141 struct s3c2410_dma_regstate state;
142
143 dmadbg_capture(chan, &state);
144 dmadbg_dumpregs(fname, line, chan, &state);
136} 145}
137 146
138#define dbg_showregs(chan) dmadbg_showregs(__FUNCTION__, __LINE__, (chan)) 147#define dbg_showregs(chan) dmadbg_showregs(__FUNCTION__, __LINE__, (chan))
@@ -253,10 +262,14 @@ s3c2410_dma_loadbuffer(s3c2410_dma_chan_t *chan,
253 buf->next); 262 buf->next);
254 reload = (buf->next == NULL) ? S3C2410_DCON_NORELOAD : 0; 263 reload = (buf->next == NULL) ? S3C2410_DCON_NORELOAD : 0;
255 } else { 264 } else {
256 pr_debug("load_state is %d => autoreload\n", chan->load_state); 265 //pr_debug("load_state is %d => autoreload\n", chan->load_state);
257 reload = S3C2410_DCON_AUTORELOAD; 266 reload = S3C2410_DCON_AUTORELOAD;
258 } 267 }
259 268
269 if ((buf->data & 0xf0000000) != 0x30000000) {
270 dmawarn("dmaload: buffer is %p\n", (void *)buf->data);
271 }
272
260 writel(buf->data, chan->addr_reg); 273 writel(buf->data, chan->addr_reg);
261 274
262 dma_wrreg(chan, S3C2410_DMA_DCON, 275 dma_wrreg(chan, S3C2410_DMA_DCON,
@@ -370,7 +383,7 @@ static int s3c2410_dma_start(s3c2410_dma_chan_t *chan)
370 tmp |= S3C2410_DMASKTRIG_ON; 383 tmp |= S3C2410_DMASKTRIG_ON;
371 dma_wrreg(chan, S3C2410_DMA_DMASKTRIG, tmp); 384 dma_wrreg(chan, S3C2410_DMA_DMASKTRIG, tmp);
372 385
373 pr_debug("wrote %08lx to DMASKTRIG\n", tmp); 386 pr_debug("dma%d: %08lx to DMASKTRIG\n", chan->number, tmp);
374 387
375#if 0 388#if 0
376 /* the dma buffer loads should take care of clearing the AUTO 389 /* the dma buffer loads should take care of clearing the AUTO
@@ -384,7 +397,30 @@ static int s3c2410_dma_start(s3c2410_dma_chan_t *chan)
384 397
385 dbg_showchan(chan); 398 dbg_showchan(chan);
386 399
400 /* if we've only loaded one buffer onto the channel, then chec
401 * to see if we have another, and if so, try and load it so when
402 * the first buffer is finished, the new one will be loaded onto
403 * the channel */
404
405 if (chan->next != NULL) {
406 if (chan->load_state == S3C2410_DMALOAD_1LOADED) {
407
408 if (s3c2410_dma_waitforload(chan, __LINE__) == 0) {
409 pr_debug("%s: buff not yet loaded, no more todo\n",
410 __FUNCTION__);
411 } else {
412 chan->load_state = S3C2410_DMALOAD_1RUNNING;
413 s3c2410_dma_loadbuffer(chan, chan->next);
414 }
415
416 } else if (chan->load_state == S3C2410_DMALOAD_1RUNNING) {
417 s3c2410_dma_loadbuffer(chan, chan->next);
418 }
419 }
420
421
387 local_irq_restore(flags); 422 local_irq_restore(flags);
423
388 return 0; 424 return 0;
389} 425}
390 426
@@ -436,12 +472,11 @@ int s3c2410_dma_enqueue(unsigned int channel, void *id,
436 buf = kmem_cache_alloc(dma_kmem, GFP_ATOMIC); 472 buf = kmem_cache_alloc(dma_kmem, GFP_ATOMIC);
437 if (buf == NULL) { 473 if (buf == NULL) {
438 pr_debug("%s: out of memory (%ld alloc)\n", 474 pr_debug("%s: out of memory (%ld alloc)\n",
439 __FUNCTION__, sizeof(*buf)); 475 __FUNCTION__, (long)sizeof(*buf));
440 return -ENOMEM; 476 return -ENOMEM;
441 } 477 }
442 478
443 pr_debug("%s: new buffer %p\n", __FUNCTION__, buf); 479 //pr_debug("%s: new buffer %p\n", __FUNCTION__, buf);
444
445 //dbg_showchan(chan); 480 //dbg_showchan(chan);
446 481
447 buf->next = NULL; 482 buf->next = NULL;
@@ -537,14 +572,20 @@ s3c2410_dma_lastxfer(s3c2410_dma_chan_t *chan)
537 case S3C2410_DMALOAD_1LOADED: 572 case S3C2410_DMALOAD_1LOADED:
538 if (s3c2410_dma_waitforload(chan, __LINE__) == 0) { 573 if (s3c2410_dma_waitforload(chan, __LINE__) == 0) {
539 /* flag error? */ 574 /* flag error? */
540 printk(KERN_ERR "dma%d: timeout waiting for load\n", 575 printk(KERN_ERR "dma%d: timeout waiting for load (%s)\n",
541 chan->number); 576 chan->number, __FUNCTION__);
542 return; 577 return;
543 } 578 }
544 break; 579 break;
545 580
581 case S3C2410_DMALOAD_1LOADED_1RUNNING:
582 /* I belive in this case we do not have anything to do
583 * until the next buffer comes along, and we turn off the
584 * reload */
585 return;
586
546 default: 587 default:
547 pr_debug("dma%d: lastxfer: unhandled load_state %d with no next", 588 pr_debug("dma%d: lastxfer: unhandled load_state %d with no next\n",
548 chan->number, chan->load_state); 589 chan->number, chan->load_state);
549 return; 590 return;
550 591
@@ -629,7 +670,14 @@ s3c2410_dma_irq(int irq, void *devpw, struct pt_regs *regs)
629 } else { 670 } else {
630 } 671 }
631 672
632 if (chan->next != NULL) { 673 /* only reload if the channel is still running... our buffer done
674 * routine may have altered the state by requesting the dma channel
675 * to stop or shutdown... */
676
677 /* todo: check that when the channel is shut-down from inside this
678 * function, we cope with unsetting reload, etc */
679
680 if (chan->next != NULL && chan->state != S3C2410_DMA_IDLE) {
633 unsigned long flags; 681 unsigned long flags;
634 682
635 switch (chan->load_state) { 683 switch (chan->load_state) {
@@ -644,8 +692,8 @@ s3c2410_dma_irq(int irq, void *devpw, struct pt_regs *regs)
644 case S3C2410_DMALOAD_1LOADED: 692 case S3C2410_DMALOAD_1LOADED:
645 if (s3c2410_dma_waitforload(chan, __LINE__) == 0) { 693 if (s3c2410_dma_waitforload(chan, __LINE__) == 0) {
646 /* flag error? */ 694 /* flag error? */
647 printk(KERN_ERR "dma%d: timeout waiting for load\n", 695 printk(KERN_ERR "dma%d: timeout waiting for load (%s)\n",
648 chan->number); 696 chan->number, __FUNCTION__);
649 return IRQ_HANDLED; 697 return IRQ_HANDLED;
650 } 698 }
651 699
@@ -678,8 +726,6 @@ s3c2410_dma_irq(int irq, void *devpw, struct pt_regs *regs)
678 return IRQ_HANDLED; 726 return IRQ_HANDLED;
679} 727}
680 728
681
682
683/* s3c2410_request_dma 729/* s3c2410_request_dma
684 * 730 *
685 * get control of an dma channel 731 * get control of an dma channel
@@ -718,11 +764,17 @@ int s3c2410_dma_request(unsigned int channel, s3c2410_dma_client_t *client,
718 pr_debug("dma%d: %s : requesting irq %d\n", 764 pr_debug("dma%d: %s : requesting irq %d\n",
719 channel, __FUNCTION__, chan->irq); 765 channel, __FUNCTION__, chan->irq);
720 766
767 chan->irq_claimed = 1;
768 local_irq_restore(flags);
769
721 err = request_irq(chan->irq, s3c2410_dma_irq, IRQF_DISABLED, 770 err = request_irq(chan->irq, s3c2410_dma_irq, IRQF_DISABLED,
722 client->name, (void *)chan); 771 client->name, (void *)chan);
723 772
773 local_irq_save(flags);
774
724 if (err) { 775 if (err) {
725 chan->in_use = 0; 776 chan->in_use = 0;
777 chan->irq_claimed = 0;
726 local_irq_restore(flags); 778 local_irq_restore(flags);
727 779
728 printk(KERN_ERR "%s: cannot get IRQ %d for DMA %d\n", 780 printk(KERN_ERR "%s: cannot get IRQ %d for DMA %d\n",
@@ -730,7 +782,6 @@ int s3c2410_dma_request(unsigned int channel, s3c2410_dma_client_t *client,
730 return err; 782 return err;
731 } 783 }
732 784
733 chan->irq_claimed = 1;
734 chan->irq_enabled = 1; 785 chan->irq_enabled = 1;
735 } 786 }
736 787
@@ -810,6 +861,7 @@ static int s3c2410_dma_dostop(s3c2410_dma_chan_t *chan)
810 861
811 tmp = dma_rdreg(chan, S3C2410_DMA_DMASKTRIG); 862 tmp = dma_rdreg(chan, S3C2410_DMA_DMASKTRIG);
812 tmp |= S3C2410_DMASKTRIG_STOP; 863 tmp |= S3C2410_DMASKTRIG_STOP;
864 //tmp &= ~S3C2410_DMASKTRIG_ON;
813 dma_wrreg(chan, S3C2410_DMA_DMASKTRIG, tmp); 865 dma_wrreg(chan, S3C2410_DMA_DMASKTRIG, tmp);
814 866
815#if 0 867#if 0
@@ -819,6 +871,7 @@ static int s3c2410_dma_dostop(s3c2410_dma_chan_t *chan)
819 dma_wrreg(chan, S3C2410_DMA_DCON, tmp); 871 dma_wrreg(chan, S3C2410_DMA_DCON, tmp);
820#endif 872#endif
821 873
874 /* should stop do this, or should we wait for flush? */
822 chan->state = S3C2410_DMA_IDLE; 875 chan->state = S3C2410_DMA_IDLE;
823 chan->load_state = S3C2410_DMALOAD_NONE; 876 chan->load_state = S3C2410_DMALOAD_NONE;
824 877
@@ -827,6 +880,22 @@ static int s3c2410_dma_dostop(s3c2410_dma_chan_t *chan)
827 return 0; 880 return 0;
828} 881}
829 882
883void s3c2410_dma_waitforstop(s3c2410_dma_chan_t *chan)
884{
885 unsigned long tmp;
886 unsigned int timeout = 0x10000;
887
888 while (timeout-- > 0) {
889 tmp = dma_rdreg(chan, S3C2410_DMA_DMASKTRIG);
890
891 if (!(tmp & S3C2410_DMASKTRIG_ON))
892 return;
893 }
894
895 pr_debug("dma%d: failed to stop?\n", chan->number);
896}
897
898
830/* s3c2410_dma_flush 899/* s3c2410_dma_flush
831 * 900 *
832 * stop the channel, and remove all current and pending transfers 901 * stop the channel, and remove all current and pending transfers
@@ -837,7 +906,9 @@ static int s3c2410_dma_flush(s3c2410_dma_chan_t *chan)
837 s3c2410_dma_buf_t *buf, *next; 906 s3c2410_dma_buf_t *buf, *next;
838 unsigned long flags; 907 unsigned long flags;
839 908
840 pr_debug("%s:\n", __FUNCTION__); 909 pr_debug("%s: chan %p (%d)\n", __FUNCTION__, chan, chan->number);
910
911 dbg_showchan(chan);
841 912
842 local_irq_save(flags); 913 local_irq_save(flags);
843 914
@@ -864,11 +935,64 @@ static int s3c2410_dma_flush(s3c2410_dma_chan_t *chan)
864 } 935 }
865 } 936 }
866 937
938 dbg_showregs(chan);
939
940 s3c2410_dma_waitforstop(chan);
941
942#if 0
943 /* should also clear interrupts, according to WinCE BSP */
944 {
945 unsigned long tmp;
946
947 tmp = dma_rdreg(chan, S3C2410_DMA_DCON);
948 tmp |= S3C2410_DCON_NORELOAD;
949 dma_wrreg(chan, S3C2410_DMA_DCON, tmp);
950 }
951#endif
952
953 dbg_showregs(chan);
954
867 local_irq_restore(flags); 955 local_irq_restore(flags);
868 956
869 return 0; 957 return 0;
870} 958}
871 959
960int
961s3c2410_dma_started(s3c2410_dma_chan_t *chan)
962{
963 unsigned long flags;
964
965 local_irq_save(flags);
966
967 dbg_showchan(chan);
968
969 /* if we've only loaded one buffer onto the channel, then chec
970 * to see if we have another, and if so, try and load it so when
971 * the first buffer is finished, the new one will be loaded onto
972 * the channel */
973
974 if (chan->next != NULL) {
975 if (chan->load_state == S3C2410_DMALOAD_1LOADED) {
976
977 if (s3c2410_dma_waitforload(chan, __LINE__) == 0) {
978 pr_debug("%s: buff not yet loaded, no more todo\n",
979 __FUNCTION__);
980 } else {
981 chan->load_state = S3C2410_DMALOAD_1RUNNING;
982 s3c2410_dma_loadbuffer(chan, chan->next);
983 }
984
985 } else if (chan->load_state == S3C2410_DMALOAD_1RUNNING) {
986 s3c2410_dma_loadbuffer(chan, chan->next);
987 }
988 }
989
990
991 local_irq_restore(flags);
992
993 return 0;
994
995}
872 996
873int 997int
874s3c2410_dma_ctrl(dmach_t channel, s3c2410_chan_op_t op) 998s3c2410_dma_ctrl(dmach_t channel, s3c2410_chan_op_t op)
@@ -885,14 +1009,15 @@ s3c2410_dma_ctrl(dmach_t channel, s3c2410_chan_op_t op)
885 return s3c2410_dma_dostop(chan); 1009 return s3c2410_dma_dostop(chan);
886 1010
887 case S3C2410_DMAOP_PAUSE: 1011 case S3C2410_DMAOP_PAUSE:
888 return -ENOENT;
889
890 case S3C2410_DMAOP_RESUME: 1012 case S3C2410_DMAOP_RESUME:
891 return -ENOENT; 1013 return -ENOENT;
892 1014
893 case S3C2410_DMAOP_FLUSH: 1015 case S3C2410_DMAOP_FLUSH:
894 return s3c2410_dma_flush(chan); 1016 return s3c2410_dma_flush(chan);
895 1017
1018 case S3C2410_DMAOP_STARTED:
1019 return s3c2410_dma_started(chan);
1020
896 case S3C2410_DMAOP_TIMEOUT: 1021 case S3C2410_DMAOP_TIMEOUT:
897 return 0; 1022 return 0;
898 1023