On 2018/8/14 18:41, Jerome Brunet wrote:
> On Tue, 2018-08-14 at 02:18 -0400, 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 <hanjie.lin@xxxxxxxxxxx>
>> Signed-off-by: Hanjie Lin <hanjie.lin@xxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/pci/amlogic,meson-pcie.txt | 57 ++++++++++++++++++++++
>> 1 file changed, 57 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..48233e4
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/pci/amlogic,meson-pcie.txt
>> @@ -0,0 +1,57 @@
>> +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
>> +- clocks: Must contain an entry for each entry in clock-names.
>> +- clock-names: Must include the following entries:
>> + - "pcie"
>> + - "pcie_bus"
>> + - "pcie_general"
>> + - "pcie_mipi_en"
>
> Could you briefly describe what each clock is needed for ?
>
Yes, is this more clear?
- clock-names: Amlogic Meson AXG
Usage: required for
Value type: <stringlist>
Definition: Should contain the following entries
- "pclk" PCIe GEN 100M PLL clock
- "port" PCIe_x(A 0r B) RC clock gate
- "general" PCIe Phy clock
- "mipi" PCIe_x(A or B) 100M ref clock gate
>> +
>> +Example configuration:
>> +
>> + pcie: pcie@dffff000 {
>> + 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-gpio = <&gpio GPIOX_19 GPIO_ACTIVE_HIGH>;
>> + interrupts = <0 177 IRQ_TYPE_EDGE_RISING>;
>
> replace 0 with GIC_SPI please
Right, I will fix it.
>
>> + #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";
>> + phys = <&pcie_phy>;
>> + ranges = <0x82000000 0 0 0x0 0xf9c00000 0 0x00300000>;
>> + num-lanes = <1>;
>> + pcie-num = <1>;
>> +
>> + clocks = <&clkc CLKID_USB
>> + &clkc CLKID_MIPI_ENABLE
>> + &clkc CLKID_PCIE_A
>> + &clkc CLKID_PCIE_CML_EN0>;
>> + clock-names = "pcie_general",
>> + "pcie_refpll",
>> + "pcie_mipi_en",
>> + "pcie",
>> + "port";
>
> Several things are disturbing above:
> * pcie_general is provided by the USB clock gate ???
> * pcie_refpll: I suppose this is a copy/paste error, not used in your driver
> (and shouldn't be need BTW)
>
> suggested names:
> * pcie_general -> general
> * pcie_mipi_en -> mipi
> * pcie -> pclk
> * port (OK)
>
Thanks, we will follow your suggestion.
>> + };
>
>
> .
>
