[poky] [PATCH] genericx86: tune for i586 instead of atom

[Jonathan Liu]

On 4 September 2013 13:44, Bruce Ashfield <bruce.ashfield at gmail.com> wrote:
> On Tue, Sep 3, 2013 at 11:30 PM, Jonathan Liu <net147 at gmail.com> wrote:
>> Hi Bruce,
>>
>> The kernel output is the following:
>> Loading /vmlinuz.........ready.
>> This kernel requires the following features not present on the CPU:
>> movbe
>> Unable to boot - please use a kernel appropriate for your CPU.
>>
>> It stops at that stage and the kernel doesn't boot at all. I started
>> having this issue after switching my BSP to Linux 3.10.
>
> I take it your BSP is based on the genericx86 BSP/configuration ? The entire
> kernel build is done with:
>
> oe_runmake ${KERNEL_IMAGETYPE_FOR_MAKE} ${KERNEL_ALT_IMAGETYPE}
> CC="${KERNEL_CC}" LD="${KERNEL_LD}" ${KERNEL_EXTRA_ARGS}
>
> And unless you've put something in KERNEL_EXTRA_ARGS, that means
> the kernel configuration and its own Makefiles determine all compile flags and
> optimizations.
>
> So switching that config file should have no impact on the build.
>
> To confirm .. you are saying after that change you can boot again ? Best to
> hear from Darren/Tom or Ross on this one.
>
> Bruce

You're right. It doesn't seem to have any impact.
Please disregard this patch.

I will try to look into this further to work out what is enabling the
use of movbe in the kernel.

Regards,
Jonathan

>
>>
>> Regards,
>> Jonathan
>>
>> On 4 September 2013 13:23, Bruce Ashfield <bruce.ashfield at gmail.com> wrote:
>>> On Tue, Sep 3, 2013 at 9:43 PM, Jonathan Liu <net147 at gmail.com> wrote:
>>>> Tuning for Intel Atom CPU can in result instructions being used that are
>>>> not compatible with older x86 CPUs such as Intel Pentium Dual-Core
>>>> E2200. This can result in Linux 3.10 failing to boot with:
>>>> "This kernel requires the following features not present on the CPU:
>>>> movbe
>>>> Unable to boot - please use a kernel appropriate for your CPU.".
>>>
>>> That's a bit surprising, do you have a bootlog to share ? This tune
>>> file shouldn't
>>> impact the kernel build options, and if it is, that's a bug.
>>>
>>> If the error shows up on the switch to userspace, then that's a different story.
>>>
>>> Bruce
>>>
>>>>
>>>> Signed-off-by: Jonathan Liu <net147 at gmail.com>
>>>> ---
>>>>  meta-yocto-bsp/conf/machine/genericx86.conf | 2 +-
>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/meta-yocto-bsp/conf/machine/genericx86.conf b/meta-yocto-bsp/conf/machine/genericx86.conf
>>>> index ff5cbc9..f5d9cd5 100644
>>>> --- a/meta-yocto-bsp/conf/machine/genericx86.conf
>>>> +++ b/meta-yocto-bsp/conf/machine/genericx86.conf
>>>> @@ -3,7 +3,7 @@
>>>>
>>>>  #@DESCRIPTION: Machine configuration for generic X86 (32-bit) PCs. Supports a moderately wide range of drivers that should boot and be usable on "typical" hardware.
>>>>
>>>> -include conf/machine/include/tune-atom.inc
>>>> +include conf/machine/include/tune-i586.inc
>>>>
>>>>  MACHINE_FEATURES = "screen keyboard pci usbhost ext2 ext3 x86 wifi acpi alsa"
>>>>
>>>> --
>>>> 1.8.4
>>>>
>>>> _______________________________________________
>>>> poky mailing list
>>>> poky at yoctoproject.org
>>>> https://lists.yoctoproject.org/listinfo/poky
>>>
>>>
>>>
>>> --
>>> "Thou shalt not follow the NULL pointer, for chaos and madness await
>>> thee at its end"
>
>
>
> --
> "Thou shalt not follow the NULL pointer, for chaos and madness await
> thee at its end"