[RFC PATCH 4/5] arm64: dts: sunxi: add SCPI driven clocks and nodes for A64 MMC

[Icenowy Zheng]

11.08.2016, 07:20, "André Przywara" <andre.przywara at arm.com>:
> On 10/08/16 16:01, Icenowy Zheng wrote:
>
> Hi,
>
>>  09.08.2016, 19:58, "Andre Przywara" <andre.przywara at arm.com>:
>>>   The MMC controllers in the Allwinner A64 SoC are somewhat compatible
>>>   with the versions used in other Allwinner SoCs.
>>>   Tell Linux about the three MMC clocks that the firmware implements and
>>>   add nodes to represent the MMC controllers.
>>>   The actual hardware is capable of new transfer modes, which the driver
>>>   does not fully support yet, also the clock part has changed, but it
>>>   works like this at least for SD card accesses.
>>>
>>>   Signed-off-by: Andre Przywara <andre.przywara at arm.com>
>>>   ---
>>>    arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 61 +++++++++++++++++++++++++++
>>>    1 file changed, 61 insertions(+)
>>>
>>>   diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
>>>   index 9fc540e..0f6044b 100644
>>>   --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
>>>   +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
>>>   @@ -157,6 +157,19 @@
>>>                    compatible = "arm,scpi";
>>>                    mboxes = <&mailbox 0>;
>>>                    shmem = <&cpu_scp_mem>;
>>>   +
>>>   + clocks {
>>>   + compatible = "arm,scpi-clocks";
>>>   +
>>>   + scpi_clk: scpi_clocks {
>>>   + compatible = "arm,scpi-variable-clocks";
>>>   + #clock-cells = <1>;
>>>   + clock-indices = <0>, <1>,
>>
>>  I found a problem of the "standardize" process.
>>  There cannot be an authority to keep the clock ID standardized, in both
>
> Why would this need to be standardized? All we would need to take care
> of is matching firmware and DT. Ideally firmware generates (or provides)
> that part of the DT, so it just puts in the bits and IDs it actually
> implements.
> Actually I am more for exploiting the "name" field for a clock that SCPI
> provides. It allows clocks to be identified without knowing any ID in
> advance, up to the point where we have something like "Ethernet" as a
> clock identifier. I wonder if Linux could make use of that somehow.
Using names is a good idea. 
>
> Cheers,
> Andre
>
>>>   + <2>;
>>>   + clock-output-names = "mmc0_clk", "mmc1_clk",
>>>   + "mmc2_clk";
>>>   + };
>>>   + };
>>>            };
>>>
>>>            soc {
>>>   @@ -165,6 +178,54 @@
>>>                    #size-cells = <1>;
>>>                    ranges;
>>>
>>>   + mmc0: mmc at 1c0f000 {
>>>   + compatible = "allwinner,sun50i-a64-mmc",
>>>   + "allwinner,sun5i-a13-mmc";
>>>   + reg = <0x01c0f000 0x1000>;
>>>   + clocks = <&bus_gates 8>, <&scpi_clk 0>,
>>>   + <&scpi_clk 0>, <&scpi_clk 0>;
>>>   + clock-names = "ahb", "mmc",
>>>   + "output", "sample";
>>>   + resets = <&ahb_rst 8>;
>>>   + reset-names = "ahb";
>>>   + interrupts = <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
>>>   + status = "disabled";
>>>   + #address-cells = <1>;
>>>   + #size-cells = <0>;
>>>   + };
>>>   +
>>>   + mmc1: mmc at 1c10000 {
>>>   + compatible = "allwinner,sun50i-a64-mmc",
>>>   + "allwinner,sun5i-a13-mmc";
>>>   + reg = <0x01c10000 0x1000>;
>>>   + clocks = <&bus_gates 9>, <&scpi_clk 1>,
>>>   + <&scpi_clk 1>, <&scpi_clk 1>;
>>>   + clock-names = "ahb", "mmc",
>>>   + "output", "sample";
>>>   + resets = <&ahb_rst 9>;
>>>   + reset-names = "ahb";
>>>   + interrupts = <GIC_SPI 61 IRQ_TYPE_LEVEL_HIGH>;
>>>   + status = "disabled";
>>>   + #address-cells = <1>;
>>>   + #size-cells = <0>;
>>>   + };
>>>   +
>>>   + mmc2: mmc at 1c11000 {
>>>   + compatible = "allwinner,sun50i-a64-mmc",
>>>   + "allwinner,sun5i-a13-mmc";
>>>   + reg = <0x01c11000 0x1000>;
>>>   + clocks = <&bus_gates 10>, <&scpi_clk 2>,
>>>   + <&scpi_clk 2>, <&scpi_clk 2>;
>>>   + clock-names = "ahb", "mmc",
>>>   + "output", "sample";
>>>   + resets = <&ahb_rst 10>;
>>>   + reset-names = "ahb";
>>>   + interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
>>>   + status = "disabled";
>>>   + #address-cells = <1>;
>>>   + #size-cells = <0>;
>>>   + };
>>>   +
>>>                    pio: pinctrl at 1c20800 {
>>>                            compatible = "allwinner,sun50i-a64-pinctrl";
>>>                            reg = <0x01c20800 0x400>;
>>>   --
>>>   2.9.0
>>>
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