Hi Jaehoon,
> -----Original Message----- > From: Jaehoon Chung [mailto:jh80.ch...@samsung.com] > Sent: Thursday, July 28, 2016 4:40 PM > To: Yangbo Lu; Ziyuan Xu; u-boot@lists.denx.de; Tom Rini > Cc: Pantelis Antoniou > Subject: Re: [U-Boot] [PATCH] mmc: send CMD0 before CMD1 for some MMC > cards > > Hi Yangbo, > > On 07/28/2016 11:45 AM, Yangbo Lu wrote: > > Hi Ziyuan and Jaehoon, > > > > > >> -----Original Message----- > >> From: Ziyuan Xu [mailto:xzy...@rock-chips.com] > >> Sent: Wednesday, July 27, 2016 9:37 PM > >> To: Jaehoon Chung; Yangbo Lu; u-boot@lists.denx.de; Tom Rini > >> Cc: Pantelis Antoniou > >> Subject: Re: [U-Boot] [PATCH] mmc: send CMD0 before CMD1 for some MMC > >> cards > >> > >> > >> > >> On 2016年07月27日 19:15, Jaehoon Chung wrote: > >>> On 07/27/2016 04:28 PM, Yangbo Lu wrote: > >>>> Hi Tom, > >>>> > >>>> Could you help to assign this mmc patch reviewing to right person? > >>>> It seems no one had reviewed it for almost half year. > >>>> > >>>> And another my mmc patch also needs to be reviewed. > >>>> I submitted in May. Please help. > >>>> http://patchwork.ozlabs.org/patch/624448/ > >>>> > >>>> > >>>> Thank you very much. > >>>> > >>>> > >>>> Best regards, > >>>> Yangbo Lu > >>>> > >>>>> -----Original Message----- > >>>>> From: Yangbo Lu [mailto:yangbo...@nxp.com] > >>>>> Sent: Wednesday, March 09, 2016 11:00 AM > >>>>> To: u-boot@lists.denx.de > >>>>> Cc: Pantelis Antoniou; Yangbo Lu > >>>>> Subject: [PATCH] mmc: send CMD0 before CMD1 for some MMC cards > >>>>> > >>>>> When the MMC framework was added in u-boot, the mmc_go_idle was > >>>>> added before mmc_send_op_cond_iter in function mmc_send_op_cond > >>>>> annotating that some cards seemed to need this. Actually, we still > >>>>> need to do this in function mmc_complete_op_cond for those cards. > >>>>> This has been verified on Micron MTFC4GACAECN eMMC chip. > >>> If there is no go_idle(), then what happen? > >>> If you share the information more, i can check the more.. > >> Sounds interesting, I also want want to know what happen? > >> It seems like you failed in CMD1? The eMMC device was always in busy > >> device within 1 second? > > > > [Lu Yangbo-B47093] This was an issue which our customer reported and > required us to fix in March. > > They used NXP LS1020A platform and Micron MTFC4GACAECN eMMC, and > reported they had to add CMD0 as below. > > Otherwise it couldn’t read OCR. > > > > static int mmc_complete_op_cond(struct mmc *mmc) { > > struct mmc_cmd cmd; > > int timeout = 1000; > > uint start; > > int err; > > > > #if defined (XXX_CHANGED) > > // our eMMC chip (Micron MTFC4GACAECN) requires that it be put in > idle mode before > > // negociating the operating voltage levels. > > mmc_go_idle(mmc); > > #endif > > Well, it seems to fix workaround. mmc_go_idle() means Device Reset. > > mmc_complete_op_cond() function has added for reducing the booting time. > If mmc_go_idle() is added at here, there is no benefit, and it should be > back to old concept. > > I don't agree this patch..now. > [Lu Yangbo-B47093] Did you notice mmc_send_op_cond function? Before mmc_send_op_cond_iter sending CMD1, there always was mmc_go_idle. I don’t know why said 'Some cards seem to need this', but it must fix some issue. static int mmc_send_op_cond(struct mmc *mmc) { int err, i; /* Some cards seem to need this */ mmc_go_idle(mmc); /* Asking to the card its capabilities */ for (i = 0; i < 2; i++) { err = mmc_send_op_cond_iter(mmc, i != 0); if (err) return err; /* exit if not busy (flag seems to be inverted) */ if (mmc->ocr & OCR_BUSY) break; } mmc->op_cond_pending = 1; return 0; } Now in mmc_complete_op_cond function, there may be the same issue. Without the mmc_go_idle, mmc_send_op_cond_iter failed to get ocr. Maybe I should move mmc_go_idle just before mmc_send_op_cond_iter, like this. static int mmc_complete_op_cond(struct mmc *mmc) { struct mmc_cmd cmd; int timeout = 1000; uint start; int err; mmc->op_cond_pending = 0; if (!(mmc->ocr & OCR_BUSY)) { start = get_timer(0); while (1) { /* Some cards seem to need this */ mmc_go_idle(mmc); err = mmc_send_op_cond_iter(mmc, 1); If you think it's not proper, do you have any suggestion? :) Thanks a lot. > Best Regards, > Jaehoon Chung > > > > > > > I hadn’t reproduce this to get more details about this issue since I > didn’t have one this kind eMMC card that time. > > Thanks. > > > >>> > >>> Best Regards, > >>> Jaehoon Chung > >>> > >>>>> Signed-off-by: Yangbo Lu <yangbo...@nxp.com> > >>>>> --- > >>>>> drivers/mmc/mmc.c | 3 +++ > >>>>> 1 file changed, 3 insertions(+) > >>>>> > >>>>> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index > >>>>> ede5d6e..82e3268 > >>>>> 100644 > >>>>> --- a/drivers/mmc/mmc.c > >>>>> +++ b/drivers/mmc/mmc.c > >>>>> @@ -418,6 +418,9 @@ static int mmc_complete_op_cond(struct mmc *mmc) > >>>>> uint start; > >>>>> int err; > >>>>> > >>>>> + /* Some cards seem to need this */ > >>>>> + mmc_go_idle(mmc); > >>>>> + > >>>>> mmc->op_cond_pending = 0; > >>>>> if (!(mmc->ocr & OCR_BUSY)) { > >>>>> start = get_timer(0); > >>>>> -- > >>>>> 2.1.0.27.g96db324 > >>>> _______________________________________________ > >>>> U-Boot mailing list > >>>> U-Boot@lists.denx.de > >>>> http://lists.denx.de/mailman/listinfo/u-boot > >>>> > >>>> > >>>> > >>> _______________________________________________ > >>> U-Boot mailing list > >>> U-Boot@lists.denx.de > >>> http://lists.denx.de/mailman/listinfo/u-boot > >> > > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
