Re: [PATCH] arm64: defconfig: Enable Qualcomm UFS and QMP UFS PHY drivers as built-in

From: Krzysztof Kozlowski

Date: Fri Apr 17 2026 - 04:48:42 EST


On 17/04/2026 10:37, Shawn Guo wrote:
> On Fri, Apr 17, 2026 at 10:14:23AM +0200, Krzysztof Kozlowski wrote:
>> On 17/04/2026 05:55, Shawn Guo wrote:
>>> UFS is the primary storage for Linux rootfs across the breadth of
>>> Qualcomm development boards - Mobile, Automotive and IoT. With
>>> Qualcomm UFS host controller driver (SCSI_UFS_QCOM) and the UFS PHY
>>> driver (PHY_QCOM_QMP_UFS) as modules, developers need an initramfs
>>
>> Yes, you always need initramfs and every developer has it.
>>
>>> to boot from UFS, which adds friction to daily development workflows.
>>
>> No friction, it's both standard, easy and all of Qualcomm and Linaro
>> developers have it solved long time ago.
>
> I'm looking at a kernel regression by running git bisect, where kernel
> version string varies for every single boot. How do you usually deal
> with it by using initramfs?

No difference from every other build and boot? I build kernel and the
same step I have initramfs with modules. Whether I bisect or build
kernel for normal boot is exactly the same.

The only difference is `git bisect good`.

>
> If using initramfs is standard and easy, I wonder why Qualcomm QLI
> (meta-qcom) kernel has UFS drivers as built-in.

This I don't know. Distros do various things, but of course there might
be an argument I do not know (e.g. like it was why distros do not make
IPV6 a module).

Best regards,
Krzysztof