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author | Michael Walle | 2021-09-10 11:20:52 +0200 |
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committer | Peng Fan | 2021-09-13 11:46:50 +0800 |
commit | 285edfd7821e79de579b0bf1a7328dead2304a0b (patch) | |
tree | 8065f834531b36c340486cd1d5244834db977e84 /include | |
parent | fb8c2e8fa936f8ebe4b7cc822abe33ff620585cd (diff) |
mmc: fsl_esdhc: remove 1ms sleep in esdhc_send_cmd_common()
Since the beginning of this driver which was initially for the MPC8379
and MPC8536 SoCs, there is this spurious 1ms delay. According to the
comment it should actually be only 8 clock cycles. Esp. during EFI block
transfers, this 1ms add up to a significant delay and slows down EFI
boot.
I couldn't find any mention in the MPC8536 that there should be a delay
of 8 clock cycles between commands. The SD card specification mentions that
the clock has to be left enabled for 8 cycles after a command or
response. But I don't see how this delay will help with this.
Go ahead and just remove it. If there will ever be any regression we can
introduce a compile time flag, but for now I'd like to keep it simple.
In the split off imx driver this delay was also removed in commit
9098682200e6 ("mmc: fsl_esdhc_imx: remove the 1ms delay before sending
command").
Signed-off-by: Michael Walle <michael@walle.cc>
Diffstat (limited to 'include')
0 files changed, 0 insertions, 0 deletions