• Yinbo Zhu's avatar
    mmc: sdhci-of-esdhc: add erratum A008171 support · b1f378ab
    Yinbo Zhu authored
    In tuning mode of operation, when TBCTL[TB_EN] is set, eSDHC may report
    one of the following errors :
    1)Tuning error while running tuning operation where SYSCTL2[SAMPCLKSEL]
    will not get set even when SYSCTL2[EXTN] is reset. OR
    2)Data transaction error (e.g. IRQSTAT[DCE], IRQSTAT[DEBE]) during data
    transaction errors.
    This issue occurs when the data window sampled within eSDHC is in full
    cycle. So, in that case, eSDHC is not able to find out the start and
    end points of the data window and sets the sampling pointer at default
    location (which is middle of the internal SD clock). If this sampling
    point coincides with the data eye boundary, then it can result in the
    above mentioned errors. Impact: Tuning mode of operation for SDR50,
    SDR104 or HS200 speed modes may not work properly
    Workaround: In case eSDHC reports tuning error or data errors in tuning
    mode of operation, by add the erratum A008171 support to fix the issue.
    Signed-off-by: default avatarYinbo Zhu <yinbo.zhu@nxp.com>
    Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
    Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    b1f378ab
sdhci-of-esdhc.c 26.5 KB