Invalidatin Cortex-A9 SCU

vsiles — Mon, 12 Sep 2016 14:48:47 GMT

Hi !

I'm trying to understand how to enable ACTLR.SMP and the SCU on our own secure OS, and the Cortex-A9 TRM states that:

For the primary processor:
1. Invalidate:
• the SCU duplicate tags for all processors
• the data cache.
2. Enable the SCU.
3. Enable the data cache, set the SMP mode with ACTLR.SMP=1.

While reading Linux code, I found that the SCU is enabled quite late in the boot process (mmu is already on, and L1/L2 caches are already configured), and the only bit set at this time are ENABLE and STANDBY_ENABLE. I can't find any invalidation of the SCU tags.

Is not invalidating the SCU before enabling an issue ?
Why does Linux enables the SCU so late in the boot process ?

Best,

Re: Invalidatin Cortex-A9 SCU

Yuri — Mon, 10 Oct 2016 07:42:14 GMT

Hello,

It is assumed, that the SCU after POR is invalidated.

Have a great day,

Yuri

------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct

Answer button. Thank you!

------------------------------------------------------------------------------

i.MX ProcessorsのトピックInvalidatin Cortex-A9 SCU

Invalidatin Cortex-A9 SCU

Re: Invalidatin Cortex-A9 SCU