[U-Boot] [PATCH v7 1/2] armv8: Support loading 32-bit OS in AArch32 execution state

[Alison Wang]

York,

                No, he don’t have my 32-bit kernel image. I am not sure he is using 32-bit kernel or 64-bit kernel.

Ryan,

                I am not familiar with the boards you tested, so I have some questions, please help to work with me to find the root cause.


1.       Are you loading 32-bit kernel or 64-bit kernel?

2.       Is CONFIG_ARMV8_SWITCH_TO_EL1 defined on these boards?

3.       Are you using some secure firmware on these boards? In detail, I want to know which EL is running on these boards when calling armv8_switch_to_el2 in arch/arm/lib/bootm.c. If it is already running in EL2 when calling armv8_swith_to_el2, the attached patch with PSCI enabled is needed.


Best Regards,
Alison Wang

From: york sun
Sent: Friday, November 04, 2016 10:04 AM
To: ryan.harkin at linaro.org
Cc: Wang Huan <b18965 at freescale.com>; agraf at suse.de; Scott Wood <scott.wood at nxp.com>; Stuart Yoder <stuart.yoder at nxp.com>; Leo Li <leoyang.li at nxp.com>; fenghua at phytium.com.cn; monstr at monstr.eu; thomas.ab at samsung.com; mk7.kang at samsung.com; u-boot at lists.denx.de; Jason Jin <jason.jin at nxp.com>; Alison Wang <alison.wang at nxp.com>
Subject: Re: [PATCH v7 1/2] armv8: Support loading 32-bit OS in AArch32 execution state


Alison,

Does Ryan have your 32-bit kernel image? I think kernel 32-bit doesn't support spin table. Please work with Ryan if your PSCI patch is required for the test.

York


-------- Original Message --------
From: Ryan Harkin <ryan.harkin at linaro.org<mailto:ryan.harkin at linaro.org>>
Sent: Thursday, November 3, 2016 12:17 PM
To: york sun <york.sun at nxp.com<mailto:york.sun at nxp.com>>
Subject: Re: [PATCH v7 1/2] armv8: Support loading 32-bit OS in AArch32 execution state
CC: Alison Wang <b18965 at freescale.com<mailto:b18965 at freescale.com>>,agraf at suse.de,Scott Wood <scott.wood at nxp.com<mailto:scott.wood at nxp.com>>,Stuart Yoder <stuart.yoder at nxp.com<mailto:stuart.yoder at nxp.com>>,Leo Li <leoyang.li at nxp.com<mailto:leoyang.li at nxp.com>>,fenghua at phytium.com.cn,monstr at monstr.eu,thomas.ab at samsung.com,mk7.kang at samsung.com,u-boot at lists.denx.de,Jason Jin <jason.jin at nxp.com<mailto:jason.jin at nxp.com>>,Alison Wang <alison.wang at nxp.com<mailto:alison.wang at nxp.com>>

Hi York/Alison,

Sorry for not having had time to look at this earlier.


On 26 October 2016 at 17:54, york sun <york.sun at nxp.com<mailto:york.sun at nxp.com>> wrote:
> On 10/07/2016 11:56 PM, Alison Wang wrote:
>> To support loading a 32-bit OS, the execution state will change from
>> AArch64 to AArch32 when jumping to kernel.
>>
>> The architecture information will be got through checking FIT image,
>> then U-Boot will load 32-bit OS or 64-bit OS automatically.
>>
>> Signed-off-by: Ebony Zhu <ebony.zhu at nxp.com<mailto:ebony.zhu at nxp.com>>
>> Signed-off-by: Alison Wang <alison.wang at nxp.com<mailto:alison.wang at nxp.com>>
>> Signed-off-by: Chenhui Zhao <chenhui.zhao at nxp.com<mailto:chenhui.zhao at nxp.com>>
>> ---
>> Changes in v7:
>> - Move the call for armv8_switch_to_el2_m into this patch.
>>
>
> Reviewers,
>
> May I have your comment please? I intend to merge this set when the
> merge window opens.
>

I've just tested these two patches on ARM's FVP Foundation and AEMv8
models and ARM's Juno board.

In all cases, with this patchset, the kernel fails to start.  I see a
continuous reboot, where the kernel starts then immediately resets:

--------------------------------------------------
Starting kernel ...

resetting ...
--------------------------------------------------

So I wouldn't want to see these patches merged.

Regards,
Ryan.
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