[PATCH v3 2/2] mmc: sdhci-esdhc-imx: Add HS400 support for iMX7ULP

sbabic at denx.de sbabic at denx.de
Wed Oct 20 14:20:31 CEST 2021

> Import HS400 support for iMX7ULP B0 from the Linux kernel:
> 2eaf5a533afd ("mmc: sdhci-esdhc-imx: Add HS400 support for iMX7ULP")
> According to IC suggest, need to clear the STROBE_DLL_CTRL_RESET
> before any setting of STROBE_DLL_CTRL register.
> USDHC has register bits(bit[27~20] of register STROBE_DLL_CTRL)
> for slave sel value. If this register bits value is 0,  it needs
> 256 ref_clk cycles to update slave sel value. IC suggest to set
> bit[27~20] to 0x4, it only need 4 ref_clk cycle to update slave
> sel value. This will short the lock time of slave.
> i.MX7ULP B0 will need more time to lock the REF and SLV, so change
> to add 5us delay.
> Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov at foundries.io>
> Reviewed-by: Fabio Estevam <festevam at gmail.com>
> Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>
> Reviewed-by: Igor Opaniuk <igor.opaniuk at foundries.io>
Applied to u-boot-imx, master, thanks !

Best regards,
Stefano Babic

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de

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