REGRESSION: HiKey eMMC corruption

[John Stultz]

The last few months have been busy and I've not been ontop of my
upstream testing as well as I'd like, but today I did manage to chase
down an issue I've been seeing since 4.17-rc1 on the HiKey board,
which was causing emmc corruption and stopping the board from booting.

Symptoms usually looked like:
[    1.690448] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
...
[    1.777288] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[    1.777760] mmc0: new HS200 MMC card at address 0001
...
[   12.214381] dwmmc_k3 f723d000.dwmmc0: Unexpected command timeout, state 3
[   12.457420] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   12.536676] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   12.616827] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   12.695742] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   12.772067] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   12.850429] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   12.863384] print_req_error: I/O error, dev mmcblk0, sector 8810504
[   12.869778] Aborting journal on device mmcblk0p10-8.
[   12.887900] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   12.967509] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   13.130182] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   13.209438] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   13.302085] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   13.380462] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   13.494539] mmc_host mmc0: Bus speed (slot 0) = 24800000Hz (slot
req 400000Hz, actual 400000HZ div = 31)
[   13.571420] mmc_host mmc0: Bus speed (slot 0) = 148800000Hz (slot
req 150000000Hz, actual 148800000HZ div = 0)
[   13.640817] EXT4-fs error (device mmcblk0p10):
ext4_journal_check_start:61: Detected aborted journal
[   13.650043] EXT4-fs (mmcblk0p10): Remounting filesystem read-only

And quite often this would result in a disk that wouldn't properly
boot even with older kernels.

I've narrowed the issue down to the following change:
abd7d0972a192 ("arm64: dts: hikey: Enable HS200 mode on eMMC")

Reverting this change seems to make things work reliably for me.

Should we revert that upstream for now?

thanks
-john