On 28/10/2022 15:17, Thierry Reding wrote:
On Fri, Oct 28, 2022 at 01:35:56PM +0100, Jon Hunter wrote:
The Tegra Combined UART (TCU) is the default serial interface for Jetson
Xavier and Orin platforms and so update the bootargs for these platforms
to use the TCU.
Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
---
arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi | 2 +-
arch/arm64/boot/dts/nvidia/tegra194-p3668.dtsi | 2 +-
arch/arm64/boot/dts/nvidia/tegra234-p3737-0000+p3701-0000.dts | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
I'm a little confused now. You're certainly right that the TCU is the
serial interface, but then why haven't we seen any fallout from this?
That is, why does console=ttyS0,115200n8 still work just fine?
For Jetson Xavier platforms, ttyS0 is the UART on the 40-pin header and
yes could be used, but probably not obvious. I thought about keeping
both and we could if we wanted. I certainly have not used ttyS0 on Orin.
Looking a little more into stdout-path (which we already point to the
TCU), that ends up adding TCU as the preferred console already. So I
wonder if we really need to set the console here at all.
>
Do you see any difference in behavior after this patch? Does it fix
anything? Could you perhaps try to remove this option altogether and see
if that makes a difference?
I wondered about that, but I was not seeing any console until the rootfs
was mounted. However, looking at of_console_check() it appears that the
cmdline takes precedence over stdout-path. OK, let me try removing the
bootargs all together.
Jon
--
nvpublic
