Re: [PATCH v9 2/2] tty: serial: meson: Add a earlycon for the T7 SoC

From: Dmitry Rokosov
Date: Wed Aug 23 2023 - 04:36:02 EST


Hello Lucas,

Thank you for the patch! Please find my small comment below.

On Mon, Aug 14, 2023 at 09:01:28AM +0100, Lucas Tanure wrote:
> The new Amlogic T7 SoC does not have a always-on uart,
> so add OF_EARLYCON_DECLARE for it.
>
> Signed-off-by: Lucas Tanure <tanure@xxxxxxxxx>
> Acked-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> ---
> Since v8:
> - Fix issues with git send-mail command line
> Since v7:
> - Send to the correct maintainers
>
> drivers/tty/serial/meson_uart.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
> index 790d910dafa5..c4f61d82fb72 100644
> --- a/drivers/tty/serial/meson_uart.c
> +++ b/drivers/tty/serial/meson_uart.c
> @@ -648,6 +648,8 @@ meson_serial_early_console_setup(struct earlycon_device *device, const char *opt
>
> OF_EARLYCON_DECLARE(meson, "amlogic,meson-ao-uart",
> meson_serial_early_console_setup);
> +OF_EARLYCON_DECLARE(meson, "amlogic,t7-uart",
> + meson_serial_early_console_setup);
>
> #define MESON_SERIAL_CONSOLE_PTR(_devname) (&meson_serial_console_##_devname)
> #else

I suppose you need to add a separate meson_t7_uart_data to switch the T7
UART to a regular TTY devname 'ttyS'. For the new Amlogic SoCs, we have
agreed to use 'ttyS' instead of 'ttyAML'. Please refer to the already
applied patch series at [1] and the IRC discussion at [2].

Links:
[1] https://lore.kernel.org/all/20230705181833.16137-1-ddrokosov@xxxxxxxxxxxxxx/
[2] https://libera.irclog.whitequark.org/linux-amlogic/2023-07-03

--
Thank you,
Dmitry