Hi Lee,

On Wed, 26 Aug 2015, Lee Jones wrote:

On Wed, 08 Jul 2015, Peter Griffin wrote:

quoted

These nodes are required to get the fdma and xbar driver working
on STiH407 based silicon.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
---
 arch/arm/boot/dts/stih407-family.dtsi | 59 +++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/arch/arm/boot/dts/stih407-family.dtsi b/arch/arm/boot/dts/stih407-family.dtsi
index 838b812..b6d9e20 100644
--- a/arch/arm/boot/dts/stih407-family.dtsi
+++ b/arch/arm/boot/dts/stih407-family.dtsi

@@ -565,5 +565,64 @@
 						  <&phy_port2 PHY_TYPE_USB3>;
 			};
 		};
+
+		xbar0: fdma-xbar-mpe@0 {

The unit address should match the one in the reg property.

Will fix in v2.

quoted

+			compatible = "st,fdma-xbar-1.0";

Is that a version number in the compatible string?

Yes it is the version number of the IP.

quoted

+			reg = <0x8e80000 0x1000>;
+			dma-requests = <79>;
+			#st,fdma-xbar-cells = <1>;

Why can't FDMA use the generic DMA properties?

Well the FDMA controller does, but this is a seperate piece of hw
which is really a router rather than a controller.

However I plan on temporarily removing xbar from this series,
as I think it should be re-worked to use the of_dma_router_register
and friends provided by the TI xbar driver.

It looks like the two xbar hw are serving a very similar purpose,
so once that re-work is done it can also use generic DMA propoerties
as I believe using that framework it will get registered as a controller.

quoted

+		};
+
+		fdma0: fdma-audio@0 {

Same comment as above.

Will fix in v2.

quoted

+			compatible = "st,fdma_mpe31";

DT doesn't usually like underscores.

Obviously I can trivially change it, but out of interest is there
a technical reason for doing so? Clearly it works OK with
an underscore and a quick grep reveals a lot of ste, and some tegra
and vexpress compatibles using underscore as well.

quoted

+			reg = <0x8e20000 0x20000>;
+			interrupts = <GIC_SPI 5 IRQ_TYPE_NONE>;
+			dma-channels = <16>;
+			#dma-cells = <3>;
+			st,fw-name = "fdma_STiH407_0.elf";

I've bought this up before somewhere (although there doesn't appear to
be a Firmware Maintainer), surely we should define a generic binding
for passing firmware names?  Many vendors are going to require it.

A generic binding would certainly be useful.

From what I can see TI are using: -

    ti,pm-firmware in wkup_m3_rproc.c

and Freescale are using: -

fsl,sdma-ram-script-name in imx-sdma.c

So other platforms are putting it in device tree, there are probably other
examples.

Most other STi drivers keep the firmware name in the C code, which is
usually my first preference. However with fdma it is more comlicated
as there is a seperate firmware file for each instance of the IP block.

I will see if there is a way to remove this from DT and keep it in
the driver.

quoted

+			clocks = <&clk_s_c0_flexgen CLK_FDMA>,
+				 <&clk_s_c0_flexgen CLK_EXT2F_A9>,
+				 <&clk_s_c0_flexgen CLK_EXT2F_A9>,
+				 <&clk_s_c0_flexgen CLK_EXT2F_A9>;
+			clock-names = "fdma_slim",
+				      "fdma_hi",
+				      "fdma_low",
+				      "fdma_ic";
+		};
+
+		fdma1: fdma-app@1 {

As above.

Will fix

quoted

+			compatible = "st,fdma_mpe31";

As above.

Will fix

quoted

+			reg = <0x8e40000 0x20000>;
+			interrupts = <GIC_SPI 7 IRQ_TYPE_NONE>;
+			dma-channels = <16>;
+			#dma-cells = <3>;
+			st,fdma-xbar = <&xbar0 0>;
+			st,fw-name = "fdma_STiH407_1.elf";
+			clocks = <&clk_s_c0_flexgen CLK_FDMA>,
+				 <&clk_s_c0_flexgen CLK_TX_ICN_DMU>,
+				 <&clk_s_c0_flexgen CLK_TX_ICN_DMU>,
+				 <&clk_s_c0_flexgen CLK_EXT2F_A9>;
+			clock-names = "fdma_slim",
+				      "fdma_hi",
+				      "fdma_low",
+				      "fdma_ic";
+		};
+
+		fdma2: fdma-free_running@2 {
+			compatible = "st,fdma_mpe31";
+			reg = <0x8e60000 0x20000>;
+			interrupts = <GIC_SPI 9 IRQ_TYPE_NONE>;
+			dma-channels = <16>;
+			#dma-cells = <3>;
+			st,fw-name = "fdma_STiH407_2.elf";
+			clocks = <&clk_s_c0_flexgen CLK_FDMA>,
+				 <&clk_s_c0_flexgen CLK_EXT2F_A9>,
+				 <&clk_s_c0_flexgen CLK_TX_ICN_DISP_0>,
+				 <&clk_s_c0_flexgen CLK_EXT2F_A9>;
+			clock-names = "fdma_slim",
+				      "fdma_hi",
+				      "fdma_low",
+				      "fdma_ic";
+		};
 	};
 };

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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regards,

Peter.