[U-Boot] Commit 294b91a5817147d4b7f47be2ac69bac2a1f26491 broke mpc85xx

[York Sun]

On 10/01/2014 08:11 AM, Simon Glass wrote:
> Hi York,
> 
> 
> On 30 September 2014 22:06, York Sun <yorksun at freescale.com> wrote:
>> Simon,
>>
>> I didn't notice until today the commit
>> 294b91a5817147d4b7f47be2ac69bac2a1f26491 broke at least T4240QDS. I have
>> narrowed down to these two lines in common/board_r.c
>>
>> initr_barrier,
>>         initr_malloc,
>>
>> If I move these two lines below this part
>>
>>
>> #if defined(CONFIG_SYS_INIT_RAM_LOCK) && defined(CONFIG_E500)
>>         initr_unlock_ram_in_cache,
>> #endif
>>
>>
>> U-boot boots OK on T4240QDS (I can see the prompt). But if I move them
>> anywhere above this initr_unlock_ram_in_cache, it hangs the core when
>> initializing PCI. It may break other mpc85xx platforms but I didn't have
>> time to check more today. I haven't figured out why you have to move these
>> two lines up. Please take a close look.
> 
> I could adjust this so that the ordering changes only when driver model is used.
> 
> This would be a case of putting '#ifdef CONFIG_DM' around the first
> section, then repeating it later with '#ifndef CONFIG_DM'. You can see
> that I did this for stdio out of an abundance of caution.
> 
> However, in the interests of supporting driver model on these
> platforms I wonder if it might be possible to move the cache logic
> earlier. I suspect that the unlock/invalidate should happen before
> post-relocation RAM is used.
> 
> Please take a look and let me know if that might be possible.
> Otherwise we'll have to go with the fallback.

I can change init sequence as far as I put initr_unlock_ram_in_cache before
initr_malloc, T4240QDS still boots.

I examine the code but don't understand why I have to do so. P4080DS doesn't
suffer this issue. I am going to seek some help from Scott and other in-house
experts.

> 
> BTW I don't have any of these boards. If there is one that is readily
> and cheaply available, or if you have an old one you can send me, I'd
> be happy to test on this and take a closer look at driver model
> support.

I checked but we don't have surplus. This board is relatively new and it sells
for $4000. I will keep an eye on it.

York