mmc: sdhci: add support for programmable clock mode
Host Controller v3.00 supports programmable clock mode as an optional feature. The support for this mode is indicated by non-zero value in bits 48-55 of the Capabilities register. If supported, the actual value of Clock Multiplier is one more than the value provided in the bit fields. We only set Clock Generator Select (bit 5) and SDCLK Frequency Select (bits 8-15) of the Clock Control register in case Preset Value Enable is not set, otherwise these fields are automatically set by the Host Controller based on the UHS mode selected. Also, since the maximum and minimum clock frequency in this mode can be (Base Clock * Clock Mul) and (Base Clock * Clock Mul)/1024 respectively, f_max and f_min have been recalculated to reflect this change. Tested by Zhangfei Gao with a Toshiba uhs card and general hs card, on mmp2 in SDMA mode. Signed-off-by:Arindam Nath <arindam.nath@amd.com> Reviewed-by:
Philip Rakity <prakity@marvell.com> Tested-by:
Philip Rakity <prakity@marvell.com> Acked-by:
Zhangfei Gao <zhangfei.gao@marvell.com> Signed-off-by:
Chris Ball <cjb@laptop.org>
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4d55c5a1
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