On Thu, Jul 21, 2022 at 11:14 AM Jernej Škrabec <jernej.skra...@gmail.com> wrote: > > Hi! > > Dne četrtek, 21. julij 2022 ob 13:28:59 CEST je Andre Przywara napisal(a): > > On 21/07/2022 12:03, Da Xue wrote: > > > > Hi Da, > > > > > Users were reporting non-boot on our H5 boards (ALL-H3-CC-H5). u-boot > > > gets stuck in SPL with this message for SD/eMMC respectively. > > > > > > Trying to boot from MMC1 or Trying to boot from MMC2 > > > > > > I tested about 20 MicroSD cards from different brands and some were > > > happy and some were not. Increasing the udelay to 8-10ms in > > > drivers/mmc/sunxi_mmc.c sunxi_mmc_core_init after reset seems to fix > > > the issue for the MicroSD cards. > > > > That's interesting, thanks for the report. I don't remember hearing of > > issues with MMC before, at least not in the SPL. > > I certainly experienced this issue on board in question. I vaguely remember > asking about this issue on IRC. I also tried all sorts of tweaks, but it never > occured to me that mmc reset timeout would be too short. > > Da, how did you find this?
Someone on the Armbian forum posted that they had the same problem with eMMC so I got suspicious. I scoped the MicroSD clock line and realized the frequency goes high and then drops to very low as if it never found the card. I had a hunch it was a stabilization delay and got lucky. > > I only test one other H5 board occasionally, namely OrangePi PC2, but I never > observed such issue there. I always needed about 5 attempts to boot ALL-H3-CC- > H5 board, but once it's cold booted, warm boots always succeed. I had run into this too so it didn't make any sense. I tried 5ms and it helped on some cards but not others. I know the Orange Pis do not have the series resistor for ESD protection of the SD GPIOs but that shouldn't affect this. So...who knows? > > Best regards, > Jernej > > > It's a bit odd that waiting after the *controller* reset should affect > > SD cards, and 1ms seems plenty for just the reset. > > I just checked and at least the SOFT_RESET and FIFO_RESET bits are self > > clearing. Can you try to use wait_for_bit_le32() to wait for those parts > > to finish? See sun8i_emac_eth_start() for an example. I tested some more and here's the data: sandisk ultra 64gb 9/20 with 1ms, 20/20 with 10ms sandisk ultra 16gb 2/20 with 1ms, 20/20 with 10ms sandisk extreme 16gb 6/20 with 10ms, 20/20 with 20ms Given this, I don't think it's an issue with the bit set delays. Might need more than 10ms even. I didn't change the udelay in probe. > > > > And since you mentioned it's card related: can you check whether the > > delay is actually needed somewhere else, later? At some point where we > > wait to the card to response, for instance? > > > > I am not against taking this patch, if it fixes problems for you, but > > just want to avoid that it papers over other issues. > > > > Cheers, > > Andre > > > > > Author: Da Xue <da@libre.computer> > > > Date: Wed Jul 20 19:11:55 2022 -0400 > > > > > > sunxi: raise stabilization time for mmc from 1ms to 8ms > > > > > > diff --git a/drivers/mmc/sunxi_mmc.c b/drivers/mmc/sunxi_mmc.c > > > index 1bb7b6d0e9..499e057725 100644 > > > --- a/drivers/mmc/sunxi_mmc.c > > > +++ b/drivers/mmc/sunxi_mmc.c > > > @@ -297,7 +297,7 @@ static int sunxi_mmc_core_init(struct mmc *mmc) > > > > > > /* Reset controller */ > > > writel(SUNXI_MMC_GCTRL_RESET, &priv->reg->gctrl); > > > > > > - udelay(1000); > > > + udelay(8000); This might need to be even higher. Like 20ms. > > > > > > return 0; > > > > > > } > > > > > > I don't know the implications of this change so I am seeking feedback. > > > Are other boards having this issue as well or is it specific to our > > > hardware? > > > > > > Best, > > > Da >