mxs/spi: Decrement the DMA/PIO border
This driver checks the length of transfer to be made and based
on this information, either chooses to transfer data via DMA or
PIO. Decrement this border further to gain better performace eg.
during SPI flash writes.
Empiric measurement shows that this gives extra 3kB/s write speed
with a M25P80 flash clocked at 40MHz.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c
index 138c852..21e1dca 100644
--- a/drivers/spi/spi-mxs.c
+++ b/drivers/spi/spi-mxs.c
@@ -445,7 +445,7 @@
* DMA only: 2.164808 seconds, 473.0KB/s
* Combined: 1.676276 seconds, 610.9KB/s
*/
- if (t->len <= 256) {
+ if (t->len < 32) {
writel(BM_SSP_CTRL1_DMA_ENABLE,
ssp->base + HW_SSP_CTRL1(ssp) +
STMP_OFFSET_REG_CLR);