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authorRussell King - ARM Linux <linux@arm.linux.org.uk>2011-07-21 17:14:08 +0100
committerVinod Koul <vinod.koul@intel.com>2011-07-26 15:33:29 +0530
commit760596c6b986e6345a28392cf40ee344bfd209a6 (patch)
tree4c08d2b8a0c28c4eb6ac558d672be5bb5e4eae05 /drivers/dma
parent121c8476a3c39a483326c33526e72a07661df1fc (diff)
DMA: PL08x: cleanup selection of burst size
Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/amba-pl08x.c58
1 files changed, 28 insertions, 30 deletions
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index a84db8b39ba..9aa2bd4452d 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1048,50 +1048,42 @@ pl08x_dma_tx_status(struct dma_chan *chan,
/* PrimeCell DMA extension */
struct burst_table {
- int burstwords;
+ u32 burstwords;
u32 reg;
};
static const struct burst_table burst_sizes[] = {
{
.burstwords = 256,
- .reg = (PL080_BSIZE_256 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_256 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_256,
},
{
.burstwords = 128,
- .reg = (PL080_BSIZE_128 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_128 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_128,
},
{
.burstwords = 64,
- .reg = (PL080_BSIZE_64 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_64 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_64,
},
{
.burstwords = 32,
- .reg = (PL080_BSIZE_32 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_32 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_32,
},
{
.burstwords = 16,
- .reg = (PL080_BSIZE_16 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_16 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_16,
},
{
.burstwords = 8,
- .reg = (PL080_BSIZE_8 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_8 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_8,
},
{
.burstwords = 4,
- .reg = (PL080_BSIZE_4 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_4 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .reg = PL080_BSIZE_4,
},
{
- .burstwords = 1,
- .reg = (PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT),
+ .burstwords = 0,
+ .reg = PL080_BSIZE_1,
},
};
@@ -1135,15 +1127,25 @@ static u32 pl08x_width(enum dma_slave_buswidth width)
return ~0;
}
+static u32 pl08x_burst(u32 maxburst)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(burst_sizes); i++)
+ if (burst_sizes[i].burstwords <= maxburst)
+ break;
+
+ return burst_sizes[i].reg;
+}
+
static int dma_set_runtime_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
struct pl08x_dma_chan *plchan = to_pl08x_chan(chan);
struct pl08x_driver_data *pl08x = plchan->host;
enum dma_slave_buswidth addr_width;
- u32 width, maxburst;
+ u32 width, burst, maxburst;
u32 cctl = 0;
- int i;
if (!plchan->slave)
return -EINVAL;
@@ -1173,20 +1175,16 @@ static int dma_set_runtime_config(struct dma_chan *chan,
cctl |= width << PL080_CONTROL_DWIDTH_SHIFT;
/*
- * Now decide on a maxburst:
* If this channel will only request single transfers, set this
* down to ONE element. Also select one element if no maxburst
* is specified.
*/
- if (plchan->cd->single || maxburst == 0) {
- cctl |= (PL080_BSIZE_1 << PL080_CONTROL_SB_SIZE_SHIFT) |
- (PL080_BSIZE_1 << PL080_CONTROL_DB_SIZE_SHIFT);
- } else {
- for (i = 0; i < ARRAY_SIZE(burst_sizes); i++)
- if (burst_sizes[i].burstwords <= maxburst)
- break;
- cctl |= burst_sizes[i].reg;
- }
+ if (plchan->cd->single)
+ maxburst = 1;
+
+ burst = pl08x_burst(maxburst);
+ cctl |= burst << PL080_CONTROL_SB_SIZE_SHIFT;
+ cctl |= burst << PL080_CONTROL_DB_SIZE_SHIFT;
if (plchan->runtime_direction == DMA_FROM_DEVICE) {
plchan->src_addr = config->src_addr;