[PATCH] arch: arm64: dts: add delay between CS and CLK signal for flash device

Meng Li Meng.Li at windriver.com
Tue Nov 2 20:38:38 PDT 2021


Based on commit d59c90a2400f("spi: spi-fsl-dspi: Convert
TCFQ users to XSPI FIFO mode ") and 6c1c26ecd9a3("spi:
spi-fsl-dspi: Accelerate transfers using larger word size if possible"),
on ls1043a-rdb platform, the spi work mode is changed from TCFQ
mode to XSPI mode. In order to keep the transmission sequence matches
with flash device, it is need to add delay between CS and CLK signal.
The strategy of generating delay value refers to QorIQ LS1043A
Reference Manual.

Signed-off-by: Meng Li <Meng.Li at windriver.com>
---
 arch/arm64/boot/dts/freescale/fsl-ls1043a-rdb.dts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1043a-rdb.dts b/arch/arm64/boot/dts/freescale/fsl-ls1043a-rdb.dts
index 3a669238a0b8..3b1a31a063c6 100644
--- a/arch/arm64/boot/dts/freescale/fsl-ls1043a-rdb.dts
+++ b/arch/arm64/boot/dts/freescale/fsl-ls1043a-rdb.dts
@@ -98,6 +98,8 @@
 		compatible = "n25q128a13", "jedec,spi-nor";  /* 16MB */
 		reg = <0>;
 		spi-max-frequency = <1000000>; /* input clock */
+		fsl,spi-cs-sck-delay = <100>;
+		fsl,spi-sck-cs-delay = <100>;
 	};
 
 	slic at 2 {
-- 
2.17.1




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