On 20 April 2017 at 10:14, Yangbo Lu <yangbo.lu@xxxxxxx> wrote: > It's complicated to support SD UHS-I and eMMC HS200 for eSDHC because > there're many differences between eSDHC and SD/eMMC spec. Several > differences as below must be considered: > 1. Peripheral clock must be used instead of platform clock. > - eSDHC could select peripheral clock or platform clock as its clock > source. According to RM, UHS-I/HS200 must use peripheral clock since > it supports higher frequency than platform clock. > - Patch 1 is to support this. > 2. Signal voltage switching requires a control circuit out of eSDHC. > - eSDHC supports signal voltage switch from 3.3v to 1.8v by > eSDHC_PROCTL[VOLT_SEL] bit. This bit changes the value of output > signal SDHC_VS, and there must be a control circuit out of eSDHC > to change the signal voltage according to SDHC_VS output signal. > - Patch 2 is to support this. > 3. eSDHC uses tuning block for tuning procedure. > - Tuning clock control register must be configured before tuning. > - Patch 3 is to support this. > 4. Delay is needed between tuning cycles for HS200 tuning. > - Once a patch removed mdelay between tuning cycles. > But eSDHC needs it. > - Patch 4 and patch 5 is to support this. > > Adrian Hunter (1): > mmc: sdhci: Control the delay between tuning commands > > Yangbo Lu (4): > mmc: sdhci-of-esdhc: add peripheral clock support > mmc: sdhci-of-esdhc: add support for signal voltage switch > mmc: sdhci-of-esdhc: add tuning support > mmc: sdhci-of-esdhc: add delay between tuning cycles > > drivers/mmc/host/sdhci-esdhc.h | 7 ++ > drivers/mmc/host/sdhci-of-esdhc.c | 168 +++++++++++++++++++++++++++++++++++++- > drivers/mmc/host/sdhci.c | 11 ++- > drivers/mmc/host/sdhci.h | 2 + > 4 files changed, 183 insertions(+), 5 deletions(-) > > -- > 2.1.0.27.g96db324 > Thanks, applied for next! Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
