Hi Nicolas,

Am 09.04.21 um 12:54 schrieb Nicolas Saenz Julienne:

Hi again,

On Wed, 2021-04-07 at 16:37 -0400, Alan Cooper wrote:

quoted

Nicolas,

I got a better description of the failure and it looks like the bus
clock needs to be limited to 300KHz for a 500MHz core clock.
What's happening is that an internal reset sequence is needed after a
command timeout and the reset signal needs to be asserted for at least
2 ticks of the bus clock. This is done using a 12 bit counter clocked
by the core clock. That means a 500MHz core clock produces a 122KHz
reset signal which is too fast for 2 ticks of the 200KHz bus clock
(100KHz) but is okay for the 300KHz (150Khz) bus clock.

Is there any value in implementing this in a generic way?

i don't have any idea which callback could manipulate the reset
duration. Limiting the min clk frequency looks like the less invasive
solution to me. Touching the DT isn't recommend.

Best regards




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