[U-Boot] [PATCH] x86: Use microcode update from device tree for all processors

Bin Meng
2018-06-12T02:05:19Z

Hi Ivan,

On Sat, Apr 21, 2018 at 1:47 AM, Ivan Gorinov <ivan.gorinov@intel.com> wrote:
> Hi Bin,
>
> On Wed, Apr 18, 2018 at 07:05:28PM -0600, Bin Meng wrote:
>> >> >
>> >> > If there is no ROM image, ucode_base and ucode_size are not initialized and
>> >> > the microcode update data from DTB applied by microcode_update_intel() to the
>> >> > bootstrap CPU is not used by the multiprocessing code.
>> >>
>> >> Correct. If it's not a ROM image, which means U-Boot is probably not
>> >> the 1st stage bootloader, which means updating microcode is not
>> >> necessary. So is there any issue with current implementation?
>> >
>> > If the 1st stage bootloader is running from the on-chip SRAM, there may be
>> > not enough space to include the microcode update data. In this case, U-Boot
>> > is a secondary boot loader but still has to update the microcode.
>>
>> Thanks for the information. Correct, if that's the case, then we
>> should tune our codes to support that.
>>
>> But I guess the "1st stage" bootloader is loaded by some on-chip
>> BOOTROM to the internal SRAM?
>
> Correct.
>
>> Is the "1st stage" bootloader running from SRAM the U-Boot SPL? Or
>> some proprietary implementation?
>
> It's usually a proprietary implementation.

Do you still see any problem with current U-Boot implementation on
microcode update? If yes, can you please respin, and resend the patch,
and describe what problem you are seeing? Otherwise, we can close this
thread.

Regards,
Bin