Re: eMMC boot problem: switch to bus width 8 ddr failed
From: Shawn Lin
Date: Mon Jan 09 2017 - 20:05:34 EST
Hi Jagan,
On 2017/1/10 6:25, Jagan Teki wrote:
On Fri, Jan 6, 2017 at 5:07 PM, Clemens Gruber
<clemens.gruber@xxxxxxxxxxxx> wrote:
On Fri, Jan 06, 2017 at 10:54:35AM +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
[ 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!
I just look into both of sdhci and sdhci-esdhc-imx again, and seems the
code miss a bit, so could you also try this one?
drivers/mmc/core/mmc_ops.c
@@ -486,7 +486,8 @@ static int mmc_poll_for_busy(struct mmc_card *card,
unsigned int timeout_ms,
busy = host->ops->card_busy(host);
} else {
err = mmc_send_status(card, &status);
- if (retry_crc_err && err == -EILSEQ) {
+ if (retry_crc_err && (err == -EILSEQ ||
+ err == -ETIMEDOUT)) {
busy = true;
} else if (err) {
return err;
Hi,
this patch (alone) does not solve the problem. The error message is the
same as before.
But applying both your first patch and this one does work. Is this one
beneficial anyway, even if it does not fix my problem?
Able to detect the eMMC, but getting kernel panic while formatting the
disk, (even remove the mmc_ops change)
Both of my test patch and Ulf's patchset didn't touch that area.
Given that the log didn't show up too much useful infomation, it
is hard to say you should blame for these change.
Could you help do git-bitsect and try to find out the problematic
commit?
Log:
----
Disk /dev/mmcblk1: 3791 MB, 3791650816 bytes
4 heads, 16 sectors/track, 115712 cylinders
Units = cylinders of 64 * 512 = 32768 bytes
Device Boot Start End Blocks Id System
/dev/mmcblk1p1 1 115712 3702776 83 Linux
Maximum filesystem blocks=4194304
29 block groups
32768 blocks per group, 32768 fragments per group
7984 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736
[ 256.769236] Kernel panic - not syncing: Attempted to kill init!
exitcode=0x00000004
[ 256.769236]
[ 256.778779] ---[ end Kernel panic - not syncing: Attempted to kill
init! exitcode=0x00000004
[ 256.778779]
Jagan.
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--
Best Regards
Shawn Lin