Re: [PATCH 4/6] riscv: dts: spacemit: enable QSPI and add SPI NOR on Milk-V Jupiter

[Yixun Lan <dlan@kernel.org>]

Hi Aurelien,

On 21:28 Sun 22 Mar     , Aurelien Jarno wrote:
> Add the QSPI controller node for the Milk-V Jupiter board and describe
> the attached SPI NOR flash (GD25Q64E).
> 
> The flash supports a frequency up to 133MHz (80 MHz for reads), and the
> SoC supports a frequency up to 104 MHz. However tests have shown that
> the flash is not reliably detected above 26.5 MHz, consistent with
> frequency used in the vendor kernel. Therefore, use this frequency.
> 
..
> The m25p,fast-read properties is taken from the vendor kernel.
> 
So long as this is verified and works fine on board?

> Add a corresponding flash partition layout, matching the layout and the
> names used in the vendor U-Boot.
> 
..
> Also add the bootph-pre-ram property to make the device tree usable by
> early firmware/bootloaders without modification, as U-Boot is stored on
> this NOR flash.
Is the dtb file actually used by U-Boot? I'd highly doubt about this,
if not the case or has not been tested, I'd suggest then not to add
this property..

> 
> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
> ---
>  .../boot/dts/spacemit/k1-milkv-jupiter.dts    | 44 ++++++++++++++++++-
>  1 file changed, 43 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/boot/dts/spacemit/k1-milkv-jupiter.dts b/arch/riscv/boot/dts/spacemit/k1-milkv-jupiter.dts
> index 836311c3f035c..05ab5df50be51 100644
> --- a/arch/riscv/boot/dts/spacemit/k1-milkv-jupiter.dts
> +++ b/arch/riscv/boot/dts/spacemit/k1-milkv-jupiter.dts
> @@ -173,7 +173,7 @@ buck3_1v8: buck3 {
>  				regulator-always-on;
>  			};
>  
> -			buck4 {
> +			buck4_3v3: buck4 {
>  				regulator-min-microvolt = <500000>;
>  				regulator-max-microvolt = <3300000>;
>  				regulator-ramp-delay = <5000>;
> @@ -256,6 +256,48 @@ dldo7 {
>  	};
>  };
>  
> +&qspi {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&qspi_cfg>;
> +	status = "okay";
> +
> +	flash@0 {
> +		compatible = "jedec,spi-nor";
> +		reg = <0>;
> +		spi-max-frequency = <26500000>;
> +		spi-rx-bus-width = <4>;
> +		spi-tx-bus-width = <4>;
> +		vcc-supply = <&buck4_3v3>; /* QSPI_VCC1833 */
> +		m25p,fast-read;
> +		bootph-pre-ram;
> +
> +		partitions {
> +			compatible = "fixed-partitions";
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +
> +			bootinfo@0 {
> +				reg = <0x0 0x10000>;
> +			};
> +			private@10000 {
> +				reg = <0x10000 0x10000>;
> +			};
> +			fsbl@20000 {
> +				reg = <0x20000 0x40000>;
> +			};
> +			env@60000 {
> +				reg = <0x60000 0x10000>;
> +			};
> +			opensbi@70000 {
> +				reg = <0x70000 0x30000>;
> +			};
> +			uboot@a00000 {
> +				reg = <0xa0000 0x760000>;
> +			};
> +		};
> +	};
> +};
> +
>  &uart0 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&uart0_2_cfg>;
> -- 
> 2.51.0
> 

-- 
Yixun Lan (dlan)