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authorTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>2010-12-01 13:49:48 +0300
committerDan Williams <dan.j.williams@intel.com>2010-12-08 02:07:08 +0300
commit943d8d8bca431d6c93f17bf38f4b09c65e0a81d7 (patch)
treee9b81cba5e8c3f761a4848c4e7de73e4ab0b5aab /drivers/dma/pch_dma.c
parentcf2f9c59807f173b1c6a537fde7c83c8da876e56 (diff)
downloadlinux-943d8d8bca431d6c93f17bf38f4b09c65e0a81d7.tar.xz
dma : EG20T PCH: Fix miss-setting DMA descriptor
Currently, in case of using scatter/gather mode, head of data is not sent to destination. The cause is second descriptor address is set to NEXT. The NEXT must have head of descriptor address. This patch sets head of descriptor address to the NEXT. Acked-by: Yong Wang <youg.y.wang@intel.com> Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com> [dan.j.williams@intel.com: fixed up usage of virt_to_phys()] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma/pch_dma.c')
-rw-r--r--drivers/dma/pch_dma.c15
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/dma/pch_dma.c b/drivers/dma/pch_dma.c
index 92b679024fed..c064c89420d0 100644
--- a/drivers/dma/pch_dma.c
+++ b/drivers/dma/pch_dma.c
@@ -259,11 +259,6 @@ static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
return;
}
- channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
- channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
- channel_writel(pd_chan, SIZE, desc->regs.size);
- channel_writel(pd_chan, NEXT, desc->regs.next);
-
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
pd_chan->chan.chan_id, desc->regs.dev_addr);
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
@@ -273,10 +268,16 @@ static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
pd_chan->chan.chan_id, desc->regs.next);
- if (list_empty(&desc->tx_list))
+ if (list_empty(&desc->tx_list)) {
+ channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
+ channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
+ channel_writel(pd_chan, SIZE, desc->regs.size);
+ channel_writel(pd_chan, NEXT, desc->regs.next);
pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
- else
+ } else {
+ channel_writel(pd_chan, NEXT, desc->txd.phys);
pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
+ }
val = dma_readl(pd, CTL2);
val |= 1 << (DMA_CTL2_START_SHIFT_BITS + pd_chan->chan.chan_id);