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-rw-r--r--drivers/dma/dw_dmac.c46
1 files changed, 18 insertions, 28 deletions
diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index d3038a03503..6b456f04255 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -191,6 +191,21 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
/*----------------------------------------------------------------------*/
+static inline unsigned int dwc_fast_fls(unsigned long long v)
+{
+ /*
+ * We can be a lot more clever here, but this should take care
+ * of the most common optimization.
+ */
+ if (!(v & 7))
+ return 3;
+ else if (!(v & 3))
+ return 2;
+ else if (!(v & 1))
+ return 1;
+ return 0;
+}
+
static void dwc_dump_chan_regs(struct dw_dma_chan *dwc)
{
dev_err(chan2dev(&dwc->chan),
@@ -641,18 +656,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
return NULL;
}
- /*
- * We can be a lot more clever here, but this should take care
- * of the most common optimization.
- */
- if (!((src | dest | len) & 7))
- src_width = dst_width = 3;
- else if (!((src | dest | len) & 3))
- src_width = dst_width = 2;
- else if (!((src | dest | len) & 1))
- src_width = dst_width = 1;
- else
- src_width = dst_width = 0;
+ src_width = dst_width = dwc_fast_fls(src | dest | len);
ctllo = DWC_DEFAULT_CTLLO(chan)
| DWC_CTLL_DST_WIDTH(dst_width)
@@ -752,14 +756,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
mem = sg_dma_address(sg);
len = sg_dma_len(sg);
- if (!((mem | len) & 7))
- mem_width = 3;
- else if (!((mem | len) & 3))
- mem_width = 2;
- else if (!((mem | len) & 1))
- mem_width = 1;
- else
- mem_width = 0;
+ mem_width = dwc_fast_fls(mem | len);
slave_sg_todev_fill_desc:
desc = dwc_desc_get(dwc);
@@ -819,14 +816,7 @@ slave_sg_todev_fill_desc:
mem = sg_dma_address(sg);
len = sg_dma_len(sg);
- if (!((mem | len) & 7))
- mem_width = 3;
- else if (!((mem | len) & 3))
- mem_width = 2;
- else if (!((mem | len) & 1))
- mem_width = 1;
- else
- mem_width = 0;
+ mem_width = dwc_fast_fls(mem | len);
slave_sg_fromdev_fill_desc:
desc = dwc_desc_get(dwc);