Re: [PATCH 1/1] ARM: dts: bcm2711: Enable ddr modes on emmc2 controller

[Florian Fainelli]

On 8/29/2020 4:15 PM, Tobias Schramm wrote:
> This patch enables ddr modes for eMMC and SD storage on emmc2,
> doubling transfer speed. Previously only single data rate modes were
> used, wasting half the available throughput.
> The bcm2711 supports both SD and eMMC storage using ddr modes. Testing
> show that pcb layout of the Raspberry Pi 4 can support them, too.
>
> Signed-off-by: Tobias Schramm <t.schramm@xxxxxxxxxxx>

This depends on Stefan's patch here:

https://lore.kernel.org/linux-arm-kernel/1598651234-29826-1-git-send-email-stefan.wahren@xxxxxxxx/

I am fine with us taking the DTS patch, as long as they all land in 5.10 
at some point.

> ---
>   arch/arm/boot/dts/bcm2711-rpi-4-b.dts | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
> index 222d7825e1ab..8b61e258e906 100644
> --- a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
> +++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
> @@ -191,6 +191,8 @@ &emmc2 {
>   	vqmmc-supply = <&sd_io_1v8_reg>;
>   	vmmc-supply = <&sd_vcc_reg>;
>   	broken-cd;
> +	mmc-ddr-3_3v;
> +	sd-uhs-ddr50;
>   	status = "okay";
>   };
>   

--
Florian