armv7R: K3: am654: U-Boot

[Michal Simek]

Hi Lokesh,

On 25. 09. 20 16:17, Lokesh Vutla wrote:
> Hi Michal,
>
> On 14/09/20 8:29 pm, Michal Simek wrote:
> Hi Tom,
> 
> On 14. 09. 20 16:47, Tom Rini wrote:
>>>> On Mon, Sep 14, 2020 at 04:42:56PM +0200, Michal Simek wrote:
>>>>
>>>>> Hi Tom and Lokesh,
>>>>>
>>>>> I have been validating R5 on ZynqMP if u-boot is still working
>>>>> with latest u-boot. I found that you have added support for
>>>>> platform in subject. Can you please tell me how you use u-boot on
>>>>> R5s? Have you tried to run Linux on it too?
> 
>> The whole boot flow is captured here[0]. See if it helps
> 
>> [0] https://gitlab.denx.de/u-boot/u-boot/-/blob/master/board/ti/am65x/README

thanks.

> 
>> No, we never tried Linux on R5. But I did verify U-Boot(non-SPL) on R5 just for
>> experimentation sake, and it works well. One hurdle I faced was that by default
>> any region above 0x8000_0000 is marked as execute never. Need to setup right MPU
>> configurations before jumping to U-Boot/Linux.

I wanted to always run Linux on it. Was talking to Nicolas Pitre about
it in past but never really had time to run it but should be possible to
do so.


> 
>>>>
>>>> I'll let Lokesh point to where the design of the am65x platform has
>>>> been talked about.  But I can confirm that the combination of
>>>> am65x_evm_r5 + am65x_evm_a53 are part of my regular HW testing
>>>> cycle that I do for each PR.
> 
> Do you have any logs from that?
> 
>> I don't think anything interesting will be obtained from R5 SPL logs. Just the
>> SPL banner and boot device. Anything specific you are looking for? I am on a
>> vacation. If you insist, I can get logs once I am back from vacation (i.e.next
>> week).
> 
> I see that you use SPL and also enabling booting Linux.
> Are you also testing booting to OS?
> 
>> No.
> 
> Are you also supporting booting R5 from A53 and vice versa?
> 
>> Yes, R5 starting A53 and A53 starting R5 are supported.

ok. As I see you have remoteproc driver for it.
Is that DT binding which you are using approved via dt mailing list?
Just curious because I can't see dt binding document.

Thanks,
Michal