Hi Russell,
On 2017/3/31 2:56, Russell King - ARM Linux wrote:
> ----------------------------------------------------------------------
> On Thu, Mar 30, 2017 at 05:22:52PM +0200, Gregory CLEMENT wrote:
>> - Remove parse of child node mmc-card. Wait for a better solution.
>
> So for mcbin, I have:
>
> &ap_sdhci0 {
> bus-width = <8>;
> marvell,xenon-emmc;
> marvell,xenon-phy-type = "emmc 5.1 phy";
> /*
> * Not stable in HS modes - phy needs "more calibration", so add
> * the "slow-mode" and disable SDR104, SDR50 and DDR50 modes.
> */
> marvell,xenon-phy-slow-mode;
> no-1-8-v;
> non-removable;
> status = "okay";
> vqmmc-supply = <&v_vddo_h>;
>
> #address-cells = <1>;
> #size-cells = <0>;
> mmccard: mmccard@0 {
> compatible = "mmc-card";
> reg = <0>;
> };
> };
>
> Does this mean the "mmccard" bit is no longer required - or is it required
> for the eMMC to be detected but is no longer supported by the driver?
>
Based on the implementation in this release, "mmccard" is no longer required.
More details:
eMMC Vqmmc in Xenon is fixed without a regulator. Thus 1.8V Signaling Enable bit
in SDHC doesn't work.
As a result, Xenon driver has to skip sdhci_start_signal_voltage_switch() to avoid
checking 1.8V signaling enable bit when setting signaling voltage.
Previously, we use "mmccard" to inform Xenon driver that it is an eMMC card
and therefore sdhci_start_signal_voltage_switch() is skipped.
Currently, Xenon driver directly checks if Vqmmc regulator is provided.
Skip sdhci_start_signal_voltage_switch() if Vqmmc is fixed.
In my own opinion, it is more direct and clear, than checking eMMC card type.
Thank you.
Best regards,
Hu Ziji
> Thanks.
>
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