[U-Boot] [PATCH 00/10] sunxi: Add basic PSCI support to enable SMP on the A80's first cluster

[Chen-Yu Tsai]

On Tue, May 2, 2017 at 6:50 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
> On Tue, May 2, 2017 at 4:16 PM, Jagan Teki <jagannadh.teki at gmail.com> wrote:
>> On Fri, Jan 27, 2017 at 4:14 AM, Rask Ingemann Lambertsen
>> <rask at formelder.dk> wrote:
>>> On Wed, Jan 25, 2017 at 06:40:38PM +0800, Chen-Yu Tsai wrote:
>>>
>>> [hacking around the broken A80 TrustZone implementation]
>>>> This is doable, and it is actually what Allwinner's kernel does, but is
>>>> really hackish. The released 3.4 kernel also has the same workarounds
>>>> for A83T. So it's also possible the A83T has the same issues.
>>>
>>> FWIW, the kernel that ships with my A80 based media player produces this:
>>> [    0.000000] Linux version 3.4.39+ (lzq at sunchip-CS24-TY) (gcc version 4.6.3 20120201 (prerelease) (crosstool-NG linaro-1.13.1-2012.02-20120222 - Linaro GCC 2012.02) ) #1 SMP PREEMPT Sat Nov 14 03:33:12 UTC 2015
>>> ...
>>> [    0.262230] CPU4: failed to boot: -22
>>> [    0.302298] CPU5: failed to boot: -22
>>> [    0.342350] CPU6: failed to boot: -22
>>> [    0.382421] CPU7: failed to boot: -22
>>>
>>> So I guess you are not alone in having trouble getting PSCI to work on the
>>> A80. However, when trying out your patches, I also once or twice got a
>>> failure booting CPU2 although CPU3 and CPU4 came up fine.
>>>
>>>> So, if there's still interest in getting a working PSCI environment
>>>> for the A80/A83T, I'll look into doing a workaround patch for GIC-400.
>>>> Otherwise I'm going to go back and revive my MCPM patches for in-kernel
>>>> SMP support.
>>>
>>> I vote for whatever works. I'll also happily test it. Is there a git tree
>>> I should keep an eye on?
>>
>> Any further update on this series? I think there is an issue this wrt comment on
>> "[U-Boot,09/10] sunxi: Enable PSCI on sun9i/A80"  patch, Please send
>> the next version on once resolved. Will mark this series as
>> "Superseded"

This needs some work on the kernel side before it will work properly,
due to the A80's security features being somewhat broken. And the kernel
side fix is really ugly. To be honest I'm not much for pursuing this
right now. I'm hoping the A83T isn't broken in a similar fashion.

ChenYu