diff options
| author | Robin Gong <b38343@freescale.com> | 2014-09-11 09:18:44 +0800 |
|---|---|---|
| committer | Nitin Garg <nitin.garg@freescale.com> | 2015-04-14 14:01:30 -0500 |
| commit | 5c5bd923a370a80bb0e897a89984598c5224627f (patch) | |
| tree | 9e6abc9156f4b5bac899bda98c561d546292702a /Documentation | |
| parent | 20ee278e6eb64ec0bb9784cdb4d20a58a0c52d37 (diff) | |
spi: spi-imx: add DMA support
Enable DMA support on i.mx6. The read speed can increase from 600KB/s
to 1.2MB/s on i.mx6q. You can disable or enable dma function in dts.
If not set "dma-names" in dts, spi will use PIO mode. This patch only
validate on i.mx6, not i.mx5, but encourage ones to apply this patch
on i.mx5 since they share the same IP.
Note:
Sometime, there is a weid data in rxfifo after one full tx/rx
transfer finish by DMA on i.mx6dl, so we disable dma functhion on
i.mx6dl.
Signed-off-by: Frank Li <Frank.Li@freescale.com>
Signed-off-by: Robin Gong <b38343@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit f62caccd12c17e4cb516d43a6e4dd8a3abc1f7e0)
(cherry picked from commit b87c98a8944c76840ed1375ed4792ef608de5c01)
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt b/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt index 4256a6df9b79..aad527b357a0 100644 --- a/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt +++ b/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt @@ -7,6 +7,9 @@ Required properties: - interrupts : Should contain CSPI/eCSPI interrupt - fsl,spi-num-chipselects : Contains the number of the chipselect - cs-gpios : Specifies the gpio pins to be used for chipselects. +- dmas: DMA specifiers for tx and rx dma. See the DMA client binding, + Documentation/devicetree/bindings/dma/dma.txt +- dma-names: DMA request names should include "tx" and "rx" if present. Example: @@ -19,4 +22,6 @@ ecspi@70010000 { fsl,spi-num-chipselects = <2>; cs-gpios = <&gpio3 24 0>, /* GPIO3_24 */ <&gpio3 25 0>; /* GPIO3_25 */ + dmas = <&sdma 3 7 1>, <&sdma 4 7 2>; + dma-names = "rx", "tx"; }; |