Re: [PATCH v2 1/2] dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller

From: Hanjie Lin
Date: Mon Aug 27 2018 - 04:55:08 EST




On 2018/8/24 16:22, Jerome Brunet wrote:
> On Fri, 2018-08-24 at 15:36 +0800, Hanjie Lin wrote:
>> From: Yue Wang <yue.wang@xxxxxxxxxxx>
>>
>> The Amlogic Meson PCIe host controller is based on the Synopsys DesignWare
>> PCI core. This patch adds documentation for the DT bindings in Meson PCIe
>> controller.
>>
>> Signed-off-by: Yue Wang <yue.wang@xxxxxxxxxxx>
>> Signed-off-by: Hanjie Lin <hanjie.lin@xxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/pci/amlogic,meson-pcie.txt | 63 ++++++++++++++++++++++
>> 1 file changed, 63 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
>>
>> diff --git a/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt b/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
>> new file mode 100644
>> index 0000000..8a831d1
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
>> @@ -0,0 +1,63 @@
>> +Amlogic Meson AXG DWC PCIE SoC controller
>> +
>> +Amlogic Meson PCIe host controller is based on the Synopsys DesignWare PCI core.
>> +It shares common functions with the PCIe DesignWare core driver and
>> +inherits common properties defined in
>> +Documentation/devicetree/bindings/pci/designware-pci.txt.
>> +
>> +Additional properties are described here:
>> +
>> +Required properties:
>> +- compatible:
>> + should contain "amlogic,axg-pcie" to identify the core.
>> +- reg:
>> + Should contain the configuration address space.
>> +- reg-names: Must be
>> + - "elbi" External local bus interface registers
>> + - "cfg" Meson specific registers
>> + - "config" PCIe configuration space
>> +- reset-gpios: The GPIO to generate PCIe PERST# assert and deassert signal.
>> +- clocks: Must contain an entry for each entry in clock-names.
>> +- clock-names: Must include the following entries:
>> + - "pclk" PCIe GEN 100M PLL clock
>> + - "port" PCIe_x(A or B) RC clock gate
>> + - "general" PCIe Phy clock
>> + - "mipi" PCIe_x(A or B) 100M ref clock gate
>> +- resets: phandle to the reset lines.
>> +- reset-names: must contain "phy" and "peripheral"
>> + - "port" Port A or B reset
>> + - "apb" APB reset
>
> The above description is not coherent (phy <=> port)
>

Yes, this should be port and apb here.
We'll integrate phy driver into ctrl driver, and move phy reset to here also.

>> +
>> +Example configuration:
>> +
>> + pcie: pcie@f9800000 {
>> + compatible = "amlogic,axg-pcie", "snps,dw-pcie";
>> + reg = <0x0 0xf9800000 0x0 0x400000
>> + 0x0 0xff646000 0x0 0x2000
>> + 0x0 0xf9f00000 0x0 0x100000>;
>> + reg-names = "elbi", "cfg", "config";
>> + reset-gpios = <&gpio GPIOX_19 GPIO_ACTIVE_HIGH>;
>> + interrupts = <GIC_SPI 177 IRQ_TYPE_EDGE_RISING>;
>> + #interrupt-cells = <1>;
>> + interrupt-map-mask = <0 0 0 0>;
>> + interrupt-map = <0 0 0 0 &gic GIC_SPI 179 IRQ_TYPE_EDGE_RISING>;
>> + bus-range = <0x0 0xff>;
>> + #address-cells = <3>;
>> + #size-cells = <2>;
>> + device_type = "pci";
>
> Not described above - is it even used ?
>

It's necessary, specified in designware-pcie.txt:
- device_type:
Usage: required
Value type: <string>
Definition: Should be "pci".

>> + phys = <&pcie_phy>;
>
> Not documented and not necessary. Please remove this.
>

We'll remove phy driver and this also.

>> + ranges = <0x82000000 0 0 0x0 0xf9c00000 0 0x00300000>;
>> +
>> + clocks = <&clkc CLKID_USB
>> + &clkc CLKID_MIPI_ENABLE
>> + &clkc CLKID_PCIE_A
>> + &clkc CLKID_PCIE_CML_EN0>;
>> + clock-names = "general",
>> + "mipi",
>> + "pclk",
>> + "port";
>> + resets = <&reset RESET_PCIE_A>,
>> + <&reset RESET_PCIE_APB>;
>> + reset-names = "port",
>> + "apb";
>> + };
>
>
> .
>