Re: BUG: Cannot boot Odroid XU4 from eMMC without this patch

From: Jaehoon Chung <jh80.chung@samsung.com>
To: Krzysztof Kozlowski <krzk@kernel.org>,
	Christian Hewitt <christianshewitt@gmail.com>
Cc: "linux-samsung-soc@vger.kernel.org" 
	<linux-samsung-soc@vger.kernel.org>,
	Marian Mihailescu <mihailescu2m@gmail.com>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Sylwester Nawrocki <snawrocki@kernel.org>,
	Ulf Hansson <ulf.hansson@linaro.org>
Subject: Re: BUG: Cannot boot Odroid XU4 from eMMC without this patch
Date: Fri, 1 Oct 2021 09:40:51 +0900	[thread overview]
Message-ID: <fec1cc85-0c81-035b-fe89-1b6dedbb3bc5@samsung.com> (raw)
In-Reply-To: <CAJKOXPfUnLbhc6e_ccZxhVReV9jHsQ8aykkP=ghK-qURQLCdLA@mail.gmail.com>

On 9/27/21 8:09 PM, Krzysztof Kozlowski wrote:
> On Mon, 13 Sept 2021 at 06:32, Christian Hewitt
> <christianshewitt@gmail.com> wrote:
>>
>> https://protect2.fireeye.com/v1/url?k=6f7d4070-30e6793d-6f7ccb3f-0cc47aa8f5ba-2c8976d4b015314f&q=1&e=776d64d2-22f3-400a-a241-42af8b5f60d0&u=https%3A%2F%2Fgithub.com%2Fchewitt%2Flinux%2Fcommit%2F8a4ebfb43a394e5dc5e9fafc92a50d5e81a4f258
>>
>> If I boot any recent kernel without the above patch, the emmc module on the XU4 is not detected, see:
>>
>> Without:
>>
>> [    3.227837] mmc0: tuning execution failed: -5
>> [    3.231229] mmc0: error -5 whilst initialising MMC card
>> [    3.536450] mmc0: tuning execution failed: -5
>> [    3.539680] mmc0: error -5 whilst initialising MMC card
>> [    3.794056] mmc0: tuning execution failed: -5
>> [    3.794212] mmc0: error -5 whilst initialising MMC card
>> [    4.111097] mmc0: tuning execution failed: -5
>> [    4.115356] mmc0: error -5 whilst initialising MMC card
>> [    4.426164] mmc0: tuning execution failed: -5
>> [    4.429678] mmc0: error -5 whilst initialising MMC card
>> [    4.756226] mmc0: tuning execution failed: -5
>> [    4.760641] mmc0: error -5 whilst initialising MMC card
>>
>> With:
>>
>> [    3.305461] mmc0: new HS400 MMC card at address 0001
>> [    3.307444] mmcblk0: mmc0:0001 8GME4R 7.28 GiB
>> [    3.308132] mmcblk0boot0: mmc0:0001 8GME4R 4.00 MiB
>> [    3.309172] mmcblk0boot1: mmc0:0001 8GME4R 4.00 MiB
>> [    3.310255] mmcblk0rpmb: mmc0:0001 8GME4R 512 KiB, chardev (246:0)
>> [    3.315963]  mmcblk0: p1 p2
>>
>> The patch is sourced from a Linux 5.4 patchset used by several retro gaming distros for XU4 images shared in the HardKernel forums. I would be happy to submit it, but the original patch has no description in the commit message. Not being a coding developer myself I cannot explain whether it is correct or what it’s doing to add one. All I can do is confirm that it works, and is needed. SD card boot is not an issue.
>>
>> I’ve CC’d the original author (Marian) in case he remembers the patch and can comment. It would be good to get this upstream.
> 
> The patch might have sense but would require describing conditions -
> what MMC input and output clock settings work and which do not work.
> Also someone would need to test other Exynos5422 boards and other
> Exynos with HS200 and HS400 support (Exynos5433, Exynos7). I think
> this should not affect SD cards.

Thanks for adding me.
I didn't see XU4 booting fail with linux-5.15-rc1 kernel.

[    4.561934] mmc1: new HS400 MMC card at address 0001
[    4.572401] mmcblk1: mmc1:0001 SDW16G 14.7 GiB
[    4.602555]  mmcblk1: p1 p2 p3 p4 < p5 p6 p7 >
[    4.623201] mmcblk1boot0: mmc1:0001 SDW16G 4.00 MiB
[    4.640465] mmcblk1boot1: mmc1:0001 SDW16G 4.00 MiB

Which kernel version did you use?

Best Regards,
Jaehoon Chung

> 
> +Cc Marek, Sylwester, Jaehoon and Ulf.
> 
> Best regards,
> Krzysztof
> 