> -----Original Message----- > From: linux-mmc-owner@xxxxxxxxxxxxxxx [mailto:linux-mmc- > owner@xxxxxxxxxxxxxxx] On Behalf Of Shawn Lin > Sent: Monday, January 09, 2017 3:10 PM > To: Clemens Gruber <clemens.gruber@xxxxxxxxxxxx>; Shawn Lin > <shawn.lin@xxxxxxxxxxxxxx>; linux-mmc@xxxxxxxxxxxxxxx > Cc: shawn.lin@xxxxxxxxxxxxxx; Ulf Hansson <ulf.hansson@xxxxxxxxxx>; Linus > Walleij <linus.walleij@xxxxxxxxxx>; Adrian Hunter <adrian.hunter@xxxxxxxxx>; > A.S. Dong <aisheng.dong@xxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: eMMC boot problem: switch to bus width 8 ddr failed > > On 2017/1/6 23:56, Clemens Gruber wrote: > > On Fri, Jan 06, 2017 at 10:33:49AM +0800, Shawn Lin wrote: > >> On 2017/1/6 8:41, Clemens Gruber wrote: > >>> Hi, > >>> > >>> with the current mainline 4.10-rc2 kernel, I can no longer boot from > >>> the eMMC on my i.MX6Q board. > >>> > >>> Details: > >>> The eMMC is a Micron MTFC4GACAJCN-1M WT but as the i.MX6Q only > >>> supports eMMC 4.41 features and we did not implement voltage > >>> switching from 3.3V to 1.8V or lower, I did add no-1-8-v; (but none > >>> of the mmc-ddr or mmc-hs > >>> options) to the device tree. The bus-width is 8. > >>> > >>> With 4.9 the board booted fine, now with the current mainline 4.10 > >>> tree, I get the following (repeating) errors at boot: > >>> > >>> [ 4.326834] Waiting for root device /dev/mmcblk0p2... > >>> [ 14.563861] mmc0: Timeout waiting for hardware cmd interrupt. > >>> [ 14.569619] sdhci: =========== REGISTER DUMP (mmc0)=========== > >>> [ 14.575461] sdhci: Sys addr: 0x4e726000 | Version: 0x00000002 > >>> [ 14.581300] sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000001 > >>> [ 14.587140] sdhci: Argument: 0x00010000 | Trn mode: 0x00000013 > >>> [ 14.592979] sdhci: Present: 0x01fd8009 | Host ctl: 0x00000031 > >>> [ 14.598816] sdhci: Power: 0x00000002 | Blk gap: 0x00000080 > >>> [ 14.604654] sdhci: Wake-up: 0x00000008 | Clock: 0x0000001f > >>> [ 14.610493] sdhci: Timeout: 0x0000008f | Int stat: 0x00000000 > >>> [ 14.616332] sdhci: Int enab: 0x107f100b | Sig enab: 0x107f100b > >>> [ 14.622168] sdhci: AC12 err: 0x00000000 | Slot int: 0x00000003 > >>> [ 14.628007] sdhci: Caps: 0x07eb0000 | Caps_1: 0x0000a007 > >>> [ 14.633845] sdhci: Cmd: 0x00000d1a | Max curr: 0x00ffffff > >> > >> it shows you always fail to get resp of sending status within the > >> expected period of time. > >> > >> > >>> [ 14.639682] sdhci: Host ctl2: 0x00000000 > >>> [ 14.643611] sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x4e6f7208 > >>> [ 14.649447] sdhci: > =========================================== > >>> > >>> This repeats a few times, then more information is shown at the bottom: > >>> > >>> [ 86.893859] mmc0: Timeout waiting for hardware cmd interrupt. > >>> [ 86.899615] sdhci: =========== REGISTER DUMP (mmc0)=========== > >>> [ 86.905453] sdhci: Sys addr: 0x00000000 | Version: 0x00000002 > >>> [ 86.911291] sdhci: Blk size: 0x00000200 | Blk cnt: 0x00000001 > >>> [ 86.917129] sdhci: Argument: 0x00010000 | Trn mode: 0x00000013 > >>> [ 86.922967] sdhci: Present: 0x01fd8009 | Host ctl: 0x00000031 > >>> [ 86.928804] sdhci: Power: 0x00000002 | Blk gap: 0x00000080 > >>> [ 86.934642] sdhci: Wake-up: 0x00000008 | Clock: 0x0000001f > >>> [ 86.940479] sdhci: Timeout: 0x0000008f | Int stat: 0x00000000 > >>> [ 86.946316] sdhci: Int enab: 0x107f100b | Sig enab: 0x107f100b > >>> [ 86.952154] sdhci: AC12 err: 0x00000000 | Slot int: 0x00000003 > >>> [ 86.957992] sdhci: Caps: 0x07eb0000 | Caps_1: 0x0000a007 > >>> [ 86.963830] sdhci: Cmd: 0x00000d1a | Max curr: 0x00ffffff > >>> [ 86.969668] sdhci: Host ctl2: 0x00000000 > >>> [ 86.973596] sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x00000000 > >>> [ 86.979433] sdhci: > =========================================== > >>> [ 86.986356] mmc0: switch to bus width 8 ddr failed > >>> [ 86.991163] mmc0: error -110 whilst initialising MMC card > >>> [ 97.773859] mmc0: Timeout waiting for hardware cmd interrupt. > >>> > >>> -- > >>> > >>> After looking through the latest commits to mmc/core, I found the > >>> culprit: > >>> Commit e173f8911f091fa50ccf8cc1fa316dd5569bc470 ("mmc: core: Update > >>> CMD13 polling policy when switch to HS DDR mode") > >>> > >>> Reverting it fixes the problem. But I am unsure if that's the right > >>> course of action? > >>> > >>> Feel free to send me patches for testing! > >> > >> By looking the changes itself, it should be good from the view of spec. > >> Maybe you could try the patch below, but don't beat me if that > >> doesn't help at all. :) > >> > >> --- a/drivers/mmc/core/mmc.c > >> +++ b/drivers/mmc/core/mmc.c > >> @@ -1074,7 +1074,7 @@ static int mmc_select_hs_ddr(struct mmc_card > *card) > >> EXT_CSD_BUS_WIDTH, > >> ext_csd_bits, > >> card->ext_csd.generic_cmd6_time, > >> - MMC_TIMING_MMC_DDR52, > >> + 0, > >> true, true, true); > >> if (err) { > >> pr_err("%s: switch to bus width %d ddr failed\n", @@ > >> -1118,6 +1118,9 @@ static int mmc_select_hs_ddr(struct mmc_card *card) > >> if (err) > >> err = __mmc_set_signal_voltage(host, > >> MMC_SIGNAL_VOLTAGE_330); > >> > >> + if (!err) > >> + mmc_set_timing(host, MMC_TIMING_MMC_DDR52); > >> + > >> > >> > > > > Hi, > > > > thank you. This patch solves the problem! :) > > Again, from the view of spec, the code is fine. > > So I *guess* that seems your host driver doesn't work fine under > DDR52 when it's in 3V3 vccq. But I don't have a real hardware to debug it. Could > freescale guys help to check it? > > Hi All, Sorry for missing these email, I did a simple debug, and find the properity "no-1-8-v" has no impact for MMC DDR52 mode, after make sure the I/O voltage do not change(keep 3.3v), this issue gone, I just did a quick debug, will give the detail analysis later, but now I can confirm that commit e173f8911f (mmc: core: Update CMD13 polling policy when switch to HS DDR mode) is not the root cause. Regards, Haibo Chen > > > > > Tested-by: Clemens Gruber <clemens.gruber@xxxxxxxxxxxx> > > > > Regards, > > Clemens > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-mmc" > > in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo > > info at http://vger.kernel.org/majordomo-info.html > > > > > -- > Best Regards > Shawn Lin > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the > body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at > http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
