Re: [PATCH v3 0/2] Configuring DMA threshold value for DW-MMC controllers

["Kaustabh Chakraborty" <kauschluss@disroot.org>]

On 2026-04-15 20:32 +05:30, Kaustabh Chakraborty wrote:
> In Samsung Exynos 7870 devices with Broadcom Wi-Fi, it has been observed
> that small sized DMA transfers are unreliable and are not written
> properly, which renders the cache incoherent.
>
> Experimental observations say that DMA transfer sizes of somewhere
> around 64 to 512 are intolerable. We must thus implement a mechanism to
> fall back to PIO transfer in this case. One such approach, which this
> series implements is allowing the DMA transfer threshold, which is
> already defined in the driver, to be configurable.
>
> Note that this patch is likely to be labelled as a workaround. These
> smaller transfers seem to be successful from downstream kernels,
> however efforts to figure out how so went in vain. It is also very
> possible that the downstream Broadcom Wi-Fi SDIO driver uses PIO
> transfers as well.
>
> Signed-off-by: Kaustabh Chakraborty <kauschluss@disroot.org>

Hi, bump! What's the status of this patch series? Both patches have been
reviewed.