Re: [PATCH 8/8] arm64: dts: rockchip: Enable SD-card interface on Radxa E20C

Yao Zi
2025-03-04T20:05:58Z

On Tue, Mar 04, 2025 at 08:55:36PM +0100, Jonas Karlman wrote:
> Hi Yao Zi,
>
> On 2025-03-04 20:49, Yao Zi wrote:
> > On Tue, Mar 04, 2025 at 08:10:36PM +0800, Chukun Pan wrote:
> >> Hi,
> >>
> >>> + aliases {
> >>> + mmc0 = &sdmmc;
> >>
> >> s/mmc0/mmc1
> >
> > Will take it and add the missing pinctrl, as Jonas already pointed out.
> >
> >>> +&sdmmc {
> >>> + bus-width = <4>;
> >>> + cap-mmc-highspeed;
> >>> + cap-sd-highspeed;
> >>
> >> I think for sdcard, only cap-sd-highspeed
> >> is needed, not cap-mmc-highspeed?
> >
> > This makes sense, will remove it in the next version.
>
> Please do not remove the cap-mmc-highspeed prop, I tested the controller
> with a microSD to eMMC adapter and MMC HS speed is supported:
>
> mmc1: card 59b4 removed
> mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0)
> mmc_host mmc1: Bus speed (slot 0) = 49800000Hz (slot req 52000000Hz, actual 49800000HZ div = 0)
> mmc1: new high speed MMC card at address 0001
> mmcblk1: mmc1:0001 DG4008 7.28 GiB
> mmcblk1: p1 p2
> mmcblk1boot0: mmc1:0001 DG4008 4.00 MiB
> mmcblk1boot1: mmc1:0001 DG4008 4.00 MiB
> mmcblk1rpmb: mmc1:0001 DG4008 4.00 MiB, chardev (499:0)
>
> ~ # cat /sys/kernel/debug/mmc1/ios
> clock: 52000000 Hz
> vdd: 21 (3.3 ~ 3.4 V)
> bus mode: 2 (push-pull)
> chip select: 0 (don't care)
> power mode: 2 (on)
> bus width: 2 (4 bits)
> timing spec: 1 (mmc high-speed)
> signal voltage: 0 (3.30 V)
> driver type: 0 (driver type B)

Oops, indeed, I didn't expect the adapted usecase and thought only
sdcards could be connected through the interface.

> Regards,
> Jonas

Thanks for the correction,
Yao Zi