Re: 8641D with linux 2.6.29 did'n show second cpu

[Kumar Gala <galak@kernel.crashing.org>]

On Apr 1, 2009, at 8:36 AM, Eduard Fuchs wrote:

> Hi,
>
> Am Mittwoch 01 April 2009 06:10:36 schrieb Kumar Gala:
>> On Mar 31, 2009, at 10:06 AM, Eduard Fuchs wrote:
>>> Hi,
>>>
>>> Am Dienstag 31 M=E4rz 2009 15:20:21 schrieb Kumar Gala:
>>>> On Mar 31, 2009, at 5:15 AM, Eduard Fuchs wrote:
>>>>> Hi,
>>>>>
>>>>> I'm testing the evaluation board from freescale (MPC8641DHPCN) =20
>>>>> with
>>>>> the latest
>>>>> linux kernel (2.6.29) and the second core seems disabled. =20
>>>>> CONFIG_SPM
>>>>> is
>>>>> enabled but the /proc/cpuinfo shows only one cpu. With original
>>>>> 2.6.27 kernel
>>>>> both cpu cores appears in /proc/cpuinfo.
>>>>>
>>>>> Has anyone an idea how can i enable the second core?
>>>>
>>>> Are you using u-boot?  I can't remember if you need a newer u-=20
>>>> boot to
>>>> deal with changes in how we bring up the second core.
>>>
>>> Yes. My u-boot version is 2009.03. Are there some additional config
>>> keys for
>>> SMP support in u-boot?
>>
>> It appears we introduced a bug in v2009.03 of u-boot.
>
> I never thought that the problem could be in u-boot. I tested the =20
> board with
> u-boot v2009.01 and it works well.

the u-boot bug is that we are over-writting the page of code we need =20
to bring up the second core.  Thus when the kernel releases the 2nd =20
core it goes off in the weeds.

I've sent some patches to the u-boot list that should fix the problem =20=

by making sure that u-boot avoids using the page of memory we need for =20=

the 2nd core.

- k=