[PATCH v1 0/3] mmc: dw_mmc-rockchip: Add stability quirk for NanoPi R76S

[Marco Schirrmeister]

On Mon, Jan 12, 2026 at 2:32 AM Shawn Lin <shawn.lin at rock-chips.com> wrote:
>
> > Evidence of the failure in dmesg:
> > [Fri Jan  2 01:28:02 2026] mmc_host mmc1: Bus speed (slot 0) = 400000Hz
> > [Fri Jan  2 01:28:03 2026] mmc_host mmc1: Bus speed (slot 0) = 198000000Hz
> > [Fri Jan  2 01:28:03 2026] dwmmc_rockchip 2a310000.mmc: Successfully tuned phase to 233
> > [Fri Jan  2 01:28:04 2026] mmc_host mmc1: Bus speed (slot 0) = 400000Hz
> >
>
> Does this problem happen with all microSDs or just *a* microSD per
> your description?
> Have you ever tried to disable SDR104 support?

I tested with multiple SanDisk Extreme and Ultra.
Yes, I have tried to disable SDR104. Also others for testing. Nothing
made a difference.