Hi,

On 02/27/2016 12:43 AM, Tony Lindgren wrote:

Hi,

* Vignesh R [off-list ref] [160224 20:49]:

quoted

According to Data Manual(SPRS915P) of AM57x, TI QSPI controller on
DRA74(rev 1.1+) can support up to 64MHz in MODE-0, whereas MODE-3 is
limited to 48MHz. Hence, switch to MODE-0 for better throughput.

Signed-off-by: Vignesh R <vigneshr@ti.com>
---
 arch/arm/boot/dts/dra7-evm.dts | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/arm/boot/dts/dra7-evm.dts b/arch/arm/boot/dts/dra7-evm.dts
index cfc24e52244e..15f10bdc8c31 100644
--- a/arch/arm/boot/dts/dra7-evm.dts
+++ b/arch/arm/boot/dts/dra7-evm.dts

@@ -653,15 +653,13 @@
 	pinctrl-names = "default";
 	pinctrl-0 = <&qspi1_pins>;
 
-	spi-max-frequency = <48000000>;
+	spi-max-frequency = <64000000>;
 	m25p80@0 {
 		compatible = "s25fl256s1";
-		spi-max-frequency = <48000000>;
+		spi-max-frequency = <64000000>;
 		reg = <0>;
 		spi-tx-bus-width = <1>;
 		spi-rx-bus-width = <4>;
-		spi-cpol;
-		spi-cpha;
 		#address-cells = <1>;
 		#size-cells = <1>;
 

Do we have any earlier pre DRA74(rev 1.1)versions in use too?

Yes, there are pre 1.1 boards (production boards are all rev 1.1+), but
QSPI is broken on them due to erratas (even w/o this patch).

What about the spi-cpol and spi-cpha changes? Those should be
at least documented?

Ok, I will add a NOTE in the documentation saying "spi-cpol" and
"spi-cpha" are not supported by ti-qspi in
Documentation/devicetree/bindings/spi/ti_qspi.txt.

-- 
Regards
Vignesh