On Wed, 3 Mar 2021 at 12:00, Ulf Hansson <ulf.hans...@linaro.org> wrote: > >On Wed, 3 Mar 2021 at 07:30, DooHyun Hwang <dh0421.hw...@samsung.com> wrote: >> >> On Tue, 2 Mar 2021 at 10:38, Ulf Hansson <ulf.hans...@linaro.org> wrote: >> >On Wed, 10 Feb 2021 at 06:12, DooHyun Hwang >> ><dh0421.hw...@samsung.com> >> >wrote: >> >> >> >> A power cycle is required if CMD11 fails. >> >> CMD11 failure should be handled as no response. >> >> >> >> If there is a timeout error that means no response to the CMD11, do >> >> not send the CMD11 again and the power cycle is required. >> >> Any other errors for CMD11 are the same because CMD11 failed. >> >> >> >> On some bad SD Card, CMD11 may fail but the card may have already >> >> invoked the voltage switch sequence. >> >> In this case, it is necessary to retry without voltage switching >> >> after power cycle. >> >> >> >> Signed-off-by: DooHyun Hwang <dh0421.hw...@samsung.com> >> > >> >Applied for next, thanks! >> > >> >I took the liberty of updating the commit message a bit, to try to >> >clarify things. Moreover, I have tagged this for stable kernels. >> > >> >BTW, did you try to force the error to -EAGAIN, to keep retrying for >> >a couple of times? If so, did it end up with the same kind of errors? >> >> Thank you for reviewing this. >> >> Yes. I tested with 2 SD cards. >> I think the power cycle is needed before retrying because SD card >> doesn't respond SD_ROCR_S18A when retrying without power cycle. > >Thanks for sharing the logs and the details below! > >If I understand correctly, forcing the error to -EAGAIN combined with the >power cycle when the CMD11 fails, actually makes us succeed with the >voltage switch in the second retry. Correct?
Yes, That's right. > >In that case, it seems like a good idea to extend $subject patch to return >-EAGAIN in case we get an error from the CMD11, right? Yes, I think so. But it looks good to retry CMD11 only for a couple of times, and if it still fails, it would be better to remove SD_OCR_S18R and retry ACMD41 as before. > >[...] > >> >> #4. SD card responded with SD_ROCR_S18A from ACMD41 after power cycle, >> and change CMD11's error value to -EAGAIN // send ACMD41 + with >SD_OCR_S18R (bit[24]) >> <7>[ 156.884623] [0: kworker/0:1: 7] mmc0: starting CMD41 arg >51040000 flags 000000e1 >> // resp ACMD41 + with SD_ROCR_S18A (bit[24]) >> <7>[ 156.884975] I[0: highpool[3]: 5440] mmc0: req done (CMD41): 0: >c1ff8000 00000000 00000000 00000000 >> // send CMD11 and error occurs >> <7>[ 156.885051] [0: kworker/0:1: 7] mmc0: starting CMD11 arg >00000000 flags 00000015 >> <7>[ 156.885759] I[0: highpool[3]: 5440] mmc0: req done (CMD11): -84: >00000000 00000000 00000000 00000000 >> // retry with power cycle (tested with this patch) >> <7>[ 156.885834] [0: kworker/0:1: 7] mmc0: Signal voltage switch >failed, power cycling card >> <7>[ 156.885875] [0: kworker/0:1: 7] mmc0: clock 0Hz busmode 2 >powermode 0 cs 0 Vdd 0 width 1 timing 0 >> <7>[ 156.920185] [0: kworker/0:1: 7] mmc0: clock 400000Hz busmode 2 >powermode 2 cs 0 Vdd 18 width 1 timing 0 >> // change CMD11's error value to -EAGAIN >> <3>[ 156.932288] [0: kworker/0:1: 7] mmc_sd_get_cid: rocr=0xc1ff8000, >retries=10. err=-84 -> -11. >> <7>[ 156.932336] [0: kworker/0:1: 7] mmc0: clock 400000Hz busmode 2 >powermode 2 cs 1 Vdd 18 width 1 timing 0 >> <7>[ 156.933834] [0: kworker/0:1: 7] mmc0: starting CMD0 arg >00000000 flags 000000c0 >> <7>[ 156.934101] I[0:ung.android.mdx:10229] mmc0: req done (CMD0): 0: >00000000 00000000 00000000 00000000 >> <7>[ 156.935562] [0: kworker/0:1: 7] mmc0: clock 400000Hz busmode 2 >powermode 2 cs 0 Vdd 18 width 1 timing 0 >> <7>[ 156.937009] [0: kworker/0:1: 7] mmc0: starting CMD8 arg >000001aa flags 000002f5 >> <7>[ 156.937372] I[0:ung.android.mdx:10229] mmc0: req done (CMD8): 0: >> 000001aa 00000000 00000000 00000000 // send ACMD41 + with SD_OCR_S18R >(bit[24]) >> <7>[ 157.044190] [0: kworker/0:1: 7] mmc0: starting CMD55 arg >00000000 flags 000000f5 >> <7>[ 157.044924] I[0:ung.android.mdx:10229] mmc0: req done (CMD55): 0: >00000120 00000000 00000000 00000000 >> <7>[ 157.045023] [0: kworker/0:1: 7] mmc0: starting CMD41 arg >51040000 flags 000000e1 >> // resp ACMD41 + with SD_ROCR_S18A (bit[24]) <7>[ 157.045389] >> I[0:ung.android.mdx:10229] mmc0: req done (CMD41): 0: c1ff8000 >> 00000000 00000000 00000000 // send CMD11 and complete >> <7>[ 157.045467] [0: kworker/0:1: 7] mmc0: starting CMD11 arg >00000000 flags 00000015 >> <7>[ 157.045855] I[0: Binder:798_2: 805] mmc0: req done (CMD11): 0: >00000320 00000000 00000000 00000000 >> >> >> > >> >> --- >> >> drivers/mmc/core/core.c | 2 +- >> >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> >> >> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c >> >> index 1136b859ddd8..a6674df2a7bb 100644 >> >> --- a/drivers/mmc/core/core.c >> >> +++ b/drivers/mmc/core/core.c >> >> @@ -1207,7 +1207,7 @@ int mmc_set_uhs_voltage(struct mmc_host >> >> *host, >> >> u32 ocr) >> >> >> >> err = mmc_wait_for_cmd(host, &cmd, 0); >> >> if (err) >> >> - return err; >> >> + goto power_cycle; >> >> >> >> if (!mmc_host_is_spi(host) && (cmd.resp[0] & R1_ERROR)) >> >> return -EIO; >> >> -- >> >> 2.29.0 >> >> > >Kind regards >Uffe Thanks and regards. DooHyun Hwang.
