[U-Boot] [PATCH 08/10] x86: qemu: Add MP initialization

[Bin Meng]

Hi Simon,

On Sat, Jul 18, 2015 at 10:37 PM, Simon Glass <sjg at chromium.org> wrote:
> Hi Bin,
>
> On 15 July 2015 at 02:23, Bin Meng <bmeng.cn at gmail.com> wrote:
>> The existing MP initialization process works on QEMU multicore,
>> except that we need increase delay time for BSP to wait APs to
>> show up online. Use a Kconfig option to control the delay time
>> factor to the normal one.
>>
>> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
>> ---
>>
>>  arch/x86/cpu/mp_init.c           |  4 ++++
>>  arch/x86/cpu/qemu/Kconfig        | 11 +++++++++++
>>  arch/x86/dts/qemu-x86_i440fx.dts | 20 ++++++++++++++++++++
>>  arch/x86/dts/qemu-x86_q35.dts    | 20 ++++++++++++++++++++
>>  configs/qemu-x86_defconfig       |  4 ++++
>>  doc/README.x86                   |  5 +++++
>>  6 files changed, 64 insertions(+)
>
> Why does qemu need a longer delay? Can we put this in as a property of
> the /cpus node instead?
>

I have no idea. I suspect it is caused by QEMU's multicore simulation
is not real paralleled. Yep, we can define a parameter in the /cpus
node to control this.

Regards,
Bin