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mmc: Change the frequency to MMC_HS_52 when selecting hs400

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Per JESD84-B51 P47, host need to change frequency to <=52MHz
after setting HS_TIMING to 0x1, and host need to set the
8-bit DDR buswidth. Currently setting the frequency to 26MHz
and trying to switch 8-bit DDR buswidth resulting timeouts.

mmc dev 1 0
Select HS400 failed -110
switch to partitions #0, OK
mmc1(part 0) is current device

Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@amd.com>
This commit is contained in:
Venkatesh Yadav Abbarapu
2024-04-23 11:00:57 +05:30
committed by Tom Rini
parent fe11aa0b8c
commit efddda8f03
1 changed files with 3 additions and 3 deletions
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6
drivers/mmc/mmc.c
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@@ -997,8 +997,8 @@ static int mmc_set_card_speed(struct mmc *mmc, enum bus_mode mode,
* Extended CSD. Reconfigure the controller to run at HS mode.
*/
if (hsdowngrade) {
mmc_select_mode(mmc, MMC_HS);
mmc_set_clock(mmc, mmc_mode2freq(mmc, MMC_HS), false);
mmc_select_mode(mmc, MMC_HS_52);
mmc_set_clock(mmc, mmc_mode2freq(mmc, MMC_HS_52), false);
}
#endif
@@ -2077,7 +2077,7 @@ static int mmc_select_hs400(struct mmc *mmc)
}
/* Set back to HS */
mmc_set_card_speed(mmc, MMC_HS, true);
mmc_set_card_speed(mmc, MMC_HS_52, true);
err = mmc_hs400_prepare_ddr(mmc);
if (err)