[PATCH 3/4] phy: rockchip-emmc: configure default output tap delay

Heiko Stuebner heiko at sntech.de
Thu Jun 16 16:36:45 PDT 2016

Am Donnerstag, 12. Mai 2016, 15:43:05 schrieb Brian Norris:
> The output tap delay controls helps maintain the hold requirements for
> eMMC. The exact value is dependent on the SoC and other factors, though
> it isn't really an exact science. But the default of 0 is not very good,
> as it doesn't give the eMMC much hold time, so let's bump up to 4
> (approx 90 degree phase?). If we need to configure this any further
> (e.g., based on board or speed factors), we may need to consider a
> device tree representation.
> Suggested-by: Shawn Lin <shawn.lin at rock-chips.com>
> Signed-off-by: Brian Norris <briannorris at chromium.org>

on my rk3399-evb board the emmc still runs nicely with this patch, so

Tested-by: Heiko Stuebner <heiko at sntech.de>

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