[U-Boot] [PATCH] powerpc: e6500: Lock/unlock 1 cache instead of L1 as init_ram

[Ruchika Gupta]

> -----Original Message-----
> From: york sun
> Sent: Saturday, March 25, 2017 10:16 PM
> To: Ruchika Gupta <ruchika.gupta at nxp.com>; u-boot at lists.denx.de;
> prabhakar.khushwaha at nxp.com
> Subject: Re: [U-Boot] [PATCH] powerpc: e6500: Lock/unlock 1 cache instead
> of L1 as init_ram
> 
> On 03/01/2017 07:37 PM, Ruchika Gupta wrote:
> > Fir E6500 cores, L2 cache has been used as init_ram. L1 cache is a
> > write through cache on E6500.If lines are not locked in both L1 and L2
> > caches, crashes are observed during secure boot. This patch
> > locks/unlocks both L1 as well as L2 cache to prevent the crash.
> 
> I didn't even know you could/should lock L1. Any reason why it would crash?
> 
> York
In secure boot scenarios, L2 cache is also locked by Rom for usage and then cleared before exiting ROM. Some castouts were being observed when only L2 cache lines were being locked in uboot hinting that lines were probably not getting locked. The e6500 core expert suggested to try locking in both the caches. This seems to resolve the crashed which we were observing. 

Ruchika