[PATCH RFC 0/2] Add Renesas RPC-IF support

[PATCH RFC 0/2] Add Renesas RPC-IF support

[Sergei Shtylyov]

Hello!

Here's a set of 2 patches against the 'for-mfd-next' branch of Lee Jones's
'mfd.git' repo. Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI
flash or HyperFlash connected to the SoC to be accessed via the external
address space read mode or the manual mode. The MFD driver for RPC-IF
registers either the SPI or HyperFLash subdevice, depending on the contents
of the device tree subnode; it also provides the absract "back end" API
that can be used by the "front end" SPI/MTD drivers to talk to the real
hardware... The HyperFlash subdriver isn't ready yet, so the MFD driver
may need some updates in order to serve it, hence the RFC status...

Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.

[1/2] dt-bindings: mfd: document Renesas RPC-IF bindings
[2/2] mfd: add Renesas RPC-IF driver

MBR, Sergei

[PATCH RFC 1/2] dt-bindings: mfd: document Renesas RPC-IF bindings

[Sergei Shtylyov]

Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI flash or
HyperFlash connected to the SoC to be accessed via the external address
space read mode or the manual mode.

Document the device tree bindings for the Renesas RPC-IF found in the R-Car
gen3 SoCs.

Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

---
 Documentation/devicetree/bindings/mfd/rpc-if.txt |   52 +++++++++++++++++++++++
 1 file changed, 52 insertions(+)

Index: mfd/Documentation/devicetree/bindings/mfd/rpc-if.txt
===================================================================
--- /dev/null
+++ mfd/Documentation/devicetree/bindings/mfd/rpc-if.txt
@@ -0,0 +1,52 @@
+Renesas Reduced Pin Count Interface (RPC-IF)
+--------------------------------------------
+
+Renesas RPC-IF allows a SPI flash or HyperFlash connected to the SoC to
+be accessed via the external address space read mode or the manual mode.
+
+Required properties:
+- compatible: should be an SoC-specific compatible value, followed by
+		"renesas,rcar-gen3-rpcif" as a fallback.
+		supported SoC-specific values are:
+		"renesas,r8a77980-rpcif" (R-Car V3H),
+		"renesas,r8a77995-rpcif" (R-Car D3).
+- reg: should list 3 register areas:
+	1st for the RPC-IF registers,
+	2nd for the direct mapping read mode,
+	3rd for the write buffer area.
+- reg-names: should contain "regs", "dirmap", and "wbuf".
+- clocks: should contain the clock phandle/specifier pair for the module clock.
+- power-domains: should contain the power domain phandle/specifier pair.
+- resets: should contain the reset controller phandle/specifier pair.
+- #address-cells: should be 1.
+- #size-cells: should be 0.
+
+The flash chip itself should be represented by a subnode of the RPC-IF node.
+The flash interface is selected based on the "compatible" property of this
+subnode:
+- if it contains "jedec,spi-nor", then SPI is used;
+- if it contains "cfi-flash", then HyperFlash is used.
+
+Example:
+
+	rpc: spi@ee200000 {
+		compatible = "renesas,r8a77995-rpcif",
+			     "renesas,rcar-gen3-rpcif";
+		reg = <0 0xee200000 0 0x200>,
+		      <0 0x08000000 0 0x4000000>,
+		      <0 0xee208000 0 0x100>;
+		reg-names = "regs", "dirmap", "wbuf";
+		clocks = <&cpg CPG_MOD 917>;
+		power-domains = <&sysc R8A77995_PD_ALWAYS_ON>;
+		resets = <&cpg 917>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		flash@0 {
+			compatible = "jedec,spi-nor";
+			reg = <0>;
+			spi-max-frequency = <40000000>;
+			spi-tx-bus-width = <1>;
+			spi-rx-bus-width = <1>;
+		};
+	};

Re: [PATCH RFC 0/2] Add Renesas RPC-IF support

[Lee Jones]

On Thu, 30 May 2019, Sergei Shtylyov wrote:

> Hello!
> 
> Here's a set of 2 patches against the 'for-mfd-next' branch of Lee Jones's
> 'mfd.git' repo. Renesas Reduced Pin Count Interface (RPC-IF) allows a SPI
> flash or HyperFlash connected to the SoC to be accessed via the external
> address space read mode or the manual mode. The MFD driver for RPC-IF
> registers either the SPI or HyperFLash subdevice, depending on the contents
> of the device tree subnode; it also provides the absract "back end" API
> that can be used by the "front end" SPI/MTD drivers to talk to the real
> hardware... The HyperFlash subdriver isn't ready yet, so the MFD driver
> may need some updates in order to serve it, hence the RFC status...
> 
> Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.
> 
> [1/2] dt-bindings: mfd: document Renesas RPC-IF bindings
> [2/2] mfd: add Renesas RPC-IF driver

Please use `git` to create your cover letters.

You are missing useful information e.g. the change stats.

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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