ioat3: enable dca for completion writes

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>
This commit is contained in:
Dan Williams 2009-09-08 17:42:57 -07:00
parent 5669e31c5a
commit e61dacaeb3
2 changed files with 3 additions and 1 deletions

View File

@ -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)

View File

@ -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