пн, 24 бер. 2025 р. о 22:01 Artur Kowalski <arturkow2...@gmail.com> пише: > > Hello > > Thanks for quick response. I know UARTD is the dedicated UART for > debugging on TF101, but exposing UART over microSD > is a handy trick useful for development. As I'm doing development on
It is a handy trick indeed, but it is still just a trick and not smth that fits mainline. Maximum I can propose is picking funcmux change along with uart over sd section in transformer t20 documentation. > this tablet (bringing U-Boot's UEFI support and latest > Linux), and also still using the device on old OS I'd like to avoid > disassembling and reassembling it over and over again. I am not sure what are you doing but TF101 has full support of U-Boot as primary bootloader along with full mainline support till 6.14 including. It uses extlinux boot method and needs no intermediates or chainloading. If you wish to use U-Boot for tethered booting that is perfectly fine as well. > Others too may find the feature useful e. g. to avoid having to solder > which requires specialized equipment, skills and > is potentially dangerous for the board. Also, there already seems to be > support for that on Sunxi platforms through > CONFIG_UART0_PORT_F. > > Apart from pinmux changes, would it be acceptable to include an option > to allow switching UARTA mux to > SDB/SDD (currently this has to be selected from board's Kconfig file). > Doing so would allow to enable UART > over microSD without patching U-Boot's source without changing any > existing configuration. Then I would > keep DTS overlays and config changes local. > I am fine with any changes which may simplify debugging for you as long as they do not invade into completed device configuration without a valid reason. Device must expose a dedicated UART for debug, not a mux which breaks some device features just because you do not want to contain them locally. For example, patches which add UART-E support along with funcmux change which exposes uart-e over usd were accepted, but patch similar to yours which would reconfigure usd to uart for surface rt or p880 would be rejected. > Also, today, after running U-Boot with debug enabled, I discovered some > failed assertions in pinmux code probably > caused by my changes, I will get that fixed before sending v2. > > Best regards > Artur Kowalski > > W dniu 18.03.2025 o 09:54, Svyatoslav Ryhel pisze: > > вт, 18 бер. 2025 р. о 10:31 Artur Kowalski <arturkow2...@gmail.com> пише: > >> > >> The first patch in the series brings general pinmux support for exposing > >> UART over SDB/SDD pins on T20. The following patches bring support > >> Transformer T20 allowing to enable UART over uSD by setting > >> > >> CONFIG_TEGRA_ENABLE_UARTA=y > >> CONFIG_DEVICE_TREE_INCLUDES="tegra20-asus-transformer-uart-usd.dtsi" > >> > >> Similarily, support for UART over uSD could be brought to Ventana which > >> has uSD on the same pins as TF101, and other Ventana-based boards. > >> > > Hey there, thank you for looking into U-Boot for Tegra. If something I > > will say hurts or offends you, I am sorry it was not intentional. > > > > Anyway, apart funcmux changes, all other changes you propose are > > redundant. Asus dedicated uart for logging and console is UARTD any > > other uart configuration must not be added since it will disrupt > > existing configuration. If you need uart and cannot resolve an issue > > without it you can always solder to uart-d or locally mux sd to uart > > console fix your issue and remove it. Uart is not intended way to > > interact with Asus TF101 and doesn't need to be exposed, panel and > > fastboot console are and can be used to resolve most of issues. > > > > Best regards, > > Svyatoslav R. > > > >> Artur Kowalski (4): > >> tegra: add funcmux for exposing UART over uSD slot on Tegra 20 > >> tegra: respect CONFIG_TEGRA_ENABLE_UART* options on Transformer T20 > >> ARM: tegra: expose UART-A over uSD on Transformer T20 > >> board: asus: transformer: add DTSI file for enabling UART over uSD > >> slot > >> > >> .../tegra20-asus-transformer-uart-usd.dtsi | 31 +++++++++++++++++++ > >> arch/arm/include/asm/arch-tegra20/funcmux.h | 1 + > >> arch/arm/mach-tegra/board.c | 4 ++- > >> arch/arm/mach-tegra/tegra20/Kconfig | 4 +++ > >> drivers/pinctrl/tegra/funcmux-tegra20.c | 9 +++++- > >> include/configs/transformer-t20.h | 10 ++++++ > >> 6 files changed, 57 insertions(+), 2 deletions(-) > >> create mode 100644 arch/arm/dts/tegra20-asus-transformer-uart-usd.dtsi > >> > >> -- > >> 2.48.1 > >>
