Re: [REGRESSION] sdhci no longer detects SD cards on LX2160A

[Russell King - ARM Linux admin <linux@armlinux.org.uk>]

On Tue, Sep 17, 2019 at 10:24:57AM -0300, Fabio Estevam wrote:
> Hi Russell,
> 
> On Tue, Sep 17, 2019 at 10:10 AM Russell King - ARM Linux admin
> <linux@armlinux.org.uk> wrote:
> 
> > Will suggested reverting bd2e75633c80 ("dma-contiguous: use fallback
> > alloc_pages for single pages") which has been implicated in the same
> > problem here:
> >
> > https://www.spinics.net/lists/arm-kernel/msg750623.html
> 
> It seems that the final fix was:
> https://lore.kernel.org/patchwork/patch/1121600/
> 
> Does it work for you if we follow the same idea?
> 
> --- a/drivers/mmc/host/sdhci-of-esdhc.c
> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
> @@ -1105,6 +1105,7 @@ static int sdhci_esdhc_probe(struct platform_device *pdev)
> 
>         esdhc_init(pdev, host);
> 
> +       sdhci_enable_v4_mode(host);
>         sdhci_get_of_property(pdev);
> 
>         pltfm_host = sdhci_priv(host);

That attempts to set bit 12 of the host control register 2 (0x3e).
The LX2160A documentation states that bit 28 of 0x3c (they're 32-bit
wide registers there) is "reserved".

So, you're asking for a documented reserved bit to be set...

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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