• weijun yang's avatar
    mmc: sirf: update sdhci_sirf_execute_tuning procedure · b36ac1b4
    weijun yang authored
    For the original tuning code, delay value is set to SD Bus Clock Delay
    Register (SD_CLK_DELAY_SETTING) as (val | (Val << 7) | (val << 16)),
    which means CLK_DELAY_IN1, CLK_DELAY_IN2 and CLK_DELAY_OUT are the
    same and with 128 steps. This is doubtful. In CSR design specification
    documents CS-304575-DR-3H, this issue is clarified, the delay[13:0] in
    SD_CLK_DELAY_SETTING is simplied to the concatenation of {CLK_DELAY_IN2,
    CLK_DELAY_IN1}.
    Besides, for CMD19 tuning, no need to set CLK_DELAY_OUT([22,16]
    of SD_CLK_DELAY_SETTING).
    Signed-off-by: default avatarweijun yang <york.yang@csr.com>
    Signed-off-by: default avatarBarry Song <baohua.song@csr.com>
    Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    b36ac1b4
sdhci-sirf.c 6.51 KB