Re: beaglebone black boot failure Linux v5.15.rc1

From: Suman Anna
Date: Tue Sep 21 2021 - 12:49:37 EST


On 9/21/21 11:40 AM, H. Nikolaus Schaller wrote:
> Hi Matti, Tony,
>
>> Am 21.09.2021 um 18:07 schrieb Suman Anna <s-anna@xxxxxx>:
>>
>> Hi Matti, Tony,
>>
>> On 9/21/21 2:47 AM, Tony Lindgren wrote:
>>> * Matti Vaittinen <mazziesaccount@xxxxxxxxx> [210920 08:23]:
>>>> Finally, adding the udelay(100); (as Tony suggested) at the end of the
>>>> omap_reset_deassert() did make the oops go away even when pruss_tm was
>>>> enabled. I don't know what would be a proper fix though.
>>
>> I have been able to boot v5.15-rc1 just fine on my BBB without any additional
>> changes [1].
>
> Same for me with a v5.15-rc1 based kernel.
>
>> May I ask what is your BBB board version? My board is rev.A5C.
>
> I have an Rev B6 with EXP41 display attached. I think Matti reported a Rev C board?
>
>> I vaguely remember from all those years ago when I first enabled PRUSS on AM335x
>> that some earlier BBB versions had some issues around PRUSS.
>
> What I am not using is PRUSS so it may (or may not) be disabled in CONFIG.

Hi Nikolaus,

Irrespective of whether you enable PRUSS configs or not (it's not enabled by
default), the ti-sysc bus driver performs a enable and disable sequence during
it's probe of the pruss_tm target-module. The module quirks are applied using
the SYSC revision register value.

The module will be disabled by the time you get to the console, and thereafter
the enabling of PRUSS IP is done through pm_runtime API when the pruss module is
probed.

regards
Suman