Messages in this thread Patch in this message | | | Subject | [PATCH 09/18] ioat3: enable dca for completion writes | From | Dan Williams <> | Date | Thu, 03 Sep 2009 23:45:20 -0700 |
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Tag completion writes for direct cache access to reduce the latency of checking for descriptor completions.
Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- drivers/dma/ioat/dma_v3.c | 3 ++- drivers/dma/ioat/registers.h | 1 + 2 files changed, 3 insertions(+), 1 deletions(-)
diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c index 22af78e..0913d11 100644 --- a/drivers/dma/ioat/dma_v3.c +++ b/drivers/dma/ioat/dma_v3.c @@ -167,7 +167,8 @@ static void ioat3_cleanup_tasklet(unsigned long data) struct ioat2_dma_chan *ioat = (void *) data; ioat3_cleanup(ioat); - writew(IOAT_CHANCTRL_RUN, ioat->base.reg_base + IOAT_CHANCTRL_OFFSET); + writew(IOAT_CHANCTRL_RUN | IOAT3_CHANCTRL_COMPL_DCA_EN, + ioat->base.reg_base + IOAT_CHANCTRL_OFFSET); } static void ioat3_restart_channel(struct ioat2_dma_chan *ioat) diff --git a/drivers/dma/ioat/registers.h b/drivers/dma/ioat/registers.h index 85d04b8..97d26ea 100644 --- a/drivers/dma/ioat/registers.h +++ b/drivers/dma/ioat/registers.h @@ -84,6 +84,7 @@ /* DMA Channel Registers */ #define IOAT_CHANCTRL_OFFSET 0x00 /* 16-bit Channel Control Register */ #define IOAT_CHANCTRL_CHANNEL_PRIORITY_MASK 0xF000 +#define IOAT3_CHANCTRL_COMPL_DCA_EN 0x0200 #define IOAT_CHANCTRL_CHANNEL_IN_USE 0x0100 #define IOAT_CHANCTRL_DESCRIPTOR_ADDR_SNOOP_CONTROL 0x0020 #define IOAT_CHANCTRL_ERR_INT_EN 0x0010
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