Re: [PATCH RFC 0/2] Introduce PRU UART driver

Judith Mendez
2025-05-07T16:31:47Z

Hi Andy,

On 5/2/25 4:38 AM, Andy Shevchenko wrote:
> On Wed, Apr 30, 2025 at 07:31:11PM -0500, Judith Mendez wrote:
>> This patch series is sent as an RFC to get some initial comments
>> on the PRU UART driver.
>>
>> The ICSSM modules on am64x SoC and the PRUSS module on am62 SoC or am335x
>> SoCs have a UART sub-module. This patch series introduces the driver and the
>> corresponding binding documentation for this sub-module.
>>
>> The DTS patches for adding PRU nodes and enabling PRU UART will be added
>> in a later v1 version of the series if accepted.
>>
>> This driver has been previously tested on the following boards:
>> am64x SK, am62x SK, and am335x SK boards.
>
> The first and main question here: Have you checked the existing zillion of
> drivers and become with an idea that none of them not even close to this one
> (based on RTL)?
>

Thanks for reviewing.

I have looked through the drivers in tty/serial/8250 and I believe there
are no drivers we could leverage, especially since this driver has a
dependency on the PRU drivers for clock and power. This PORT_16550A UART
is in PRU module which is specific to TI, so besides simplifying the
driver a bit further, I don't think we can use another driver.

~ Judith