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| Started by | Vignesh R <vigneshr@ti.com> |
|---|---|
| First post | 2016-04-20 13:40 +0200 |
| Last post | 2016-04-26 20:00 +0200 |
| Articles | 3 — 3 participants |
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[PATCH v2 2/2] ARM: dts: dra7x: Support QSPI MODE-0 operation at 64MHz Vignesh R <vigneshr@ti.com> - 2016-04-20 13:40 +0200
Re: [PATCH v2 2/2] ARM: dts: dra7x: Support QSPI MODE-0 operation at 64MHz Rob Herring <robh@kernel.org> - 2016-04-22 21:40 +0200
Re: [PATCH v2 2/2] ARM: dts: dra7x: Support QSPI MODE-0 operation at 64MHz Tony Lindgren <tony@atomide.com> - 2016-04-26 20:00 +0200
| From | Vignesh R <vigneshr@ti.com> |
|---|---|
| Date | 2016-04-20 13:40 +0200 |
| Subject | [PATCH v2 2/2] ARM: dts: dra7x: Support QSPI MODE-0 operation at 64MHz |
| Message-ID | <rpYEa-7aC-17@gated-at.bofh.it> |
According to Data Manual(SPRS915P) of AM57x, TI QSPI controller on
DRA74(rev 1.1+)/DRA72 EVM 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>
---
v2: rebased on linux-next 20160419 to include moving to
dra72-evm-common.dtsi
Documentation/devicetree/bindings/spi/ti_qspi.txt | 7 +++++++
arch/arm/boot/dts/dra7-evm.dts | 6 ++----
arch/arm/boot/dts/dra72-evm-common.dtsi | 6 ++----
3 files changed, 11 insertions(+), 8 deletions(-)
diff --git a/Documentation/devicetree/bindings/spi/ti_qspi.txt b/Documentation/devicetree/bindings/spi/ti_qspi.txt
index cc8304aa64ac..50b14f6b53a3 100644
--- a/Documentation/devicetree/bindings/spi/ti_qspi.txt
+++ b/Documentation/devicetree/bindings/spi/ti_qspi.txt
@@ -19,6 +19,13 @@ Optional properties:
- syscon-chipselects: Handle to system control region contains QSPI
chipselect register and offset of that register.
+NOTE: TI QSPI controller requires different pinmux and IODelay
+paramaters for Mode-0 and Mode-3 operations, which needs to be set up by
+the bootloader (U-Boot). Default configuration only supports Mode-0
+operation. Hence, "spi-cpol" and "spi-cpha" DT properties cannot be
+specified in the slave nodes of TI QSPI controller without appropriate
+modification to bootloader.
+
Example:
For am4372:
diff --git a/arch/arm/boot/dts/dra7-evm.dts b/arch/arm/boot/dts/dra7-evm.dts
index 47d0745a08ad..507a8ec0a268 100644
--- a/arch/arm/boot/dts/dra7-evm.dts
+++ b/arch/arm/boot/dts/dra7-evm.dts
@@ -664,15 +664,13 @@
&qspi {
status = "okay";
- 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>;
diff --git a/arch/arm/boot/dts/dra72-evm-common.dtsi b/arch/arm/boot/dts/dra72-evm-common.dtsi
index beef82502ea0..e53b1ef8c7aa 100644
--- a/arch/arm/boot/dts/dra72-evm-common.dtsi
+++ b/arch/arm/boot/dts/dra72-evm-common.dtsi
@@ -681,15 +681,13 @@
&qspi {
status = "okay";
- 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>;
--
2.8.1
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| From | Rob Herring <robh@kernel.org> |
|---|---|
| Date | 2016-04-22 21:40 +0200 |
| Subject | Re: [PATCH v2 2/2] ARM: dts: dra7x: Support QSPI MODE-0 operation at 64MHz |
| Message-ID | <rqP5M-7go-19@gated-at.bofh.it> |
| In reply to | #1383319 |
On Wed, Apr 20, 2016 at 05:03:00PM +0530, Vignesh R wrote: > According to Data Manual(SPRS915P) of AM57x, TI QSPI controller on > DRA74(rev 1.1+)/DRA72 EVM 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> > --- > > v2: rebased on linux-next 20160419 to include moving to > dra72-evm-common.dtsi > > > Documentation/devicetree/bindings/spi/ti_qspi.txt | 7 +++++++ > arch/arm/boot/dts/dra7-evm.dts | 6 ++---- > arch/arm/boot/dts/dra72-evm-common.dtsi | 6 ++---- > 3 files changed, 11 insertions(+), 8 deletions(-) Acked-by: Rob Herring <robh@kernel.org>
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| From | Tony Lindgren <tony@atomide.com> |
|---|---|
| Date | 2016-04-26 20:00 +0200 |
| Subject | Re: [PATCH v2 2/2] ARM: dts: dra7x: Support QSPI MODE-0 operation at 64MHz |
| Message-ID | <rsfrc-3gJ-13@gated-at.bofh.it> |
| In reply to | #1385460 |
* Rob Herring <robh@kernel.org> [160422 12:35]: > On Wed, Apr 20, 2016 at 05:03:00PM +0530, Vignesh R wrote: > > According to Data Manual(SPRS915P) of AM57x, TI QSPI controller on > > DRA74(rev 1.1+)/DRA72 EVM 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> > > --- > > > > v2: rebased on linux-next 20160419 to include moving to > > dra72-evm-common.dtsi > > > > > > Documentation/devicetree/bindings/spi/ti_qspi.txt | 7 +++++++ > > arch/arm/boot/dts/dra7-evm.dts | 6 ++---- > > arch/arm/boot/dts/dra72-evm-common.dtsi | 6 ++---- > > 3 files changed, 11 insertions(+), 8 deletions(-) > > Acked-by: Rob Herring <robh@kernel.org> Applying both into omap-for-v4.7/dt thanks. Tony
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