On 03/21/2012 11:13 AM, Simon Glass wrote:
Hi Stephen,
On Wed, Mar 21, 2012 at 10:09 AM, Stephen Warren swarren@wwwdotorg.org wrote:
On 03/21/2012 10:59 AM, Simon Glass wrote:
- What you propose is actually very easy to implement - it just
requires a new config like CONFIG_DEFAULT_UART or CONFIG_PRE_CONSOLE_UART to be defined, and used in the board_pre_console_putc() code.
One question here: We already have CONFIG_TEGRA2_ENABLE_UART* and CONFIG_SYS_NS16550_COM* to select which UART to use. Surely one of those is appropriate for this, rather than inventing yet another config option?
These will only exist when CONFIG_OF_CONTROL is not defined. It might confusing to use the same CONFIGs for the pre-console panic() case, knowing that they will in fact be ignored in a normal boot. I would suggest a new option, at least in the CONFIG_OF_CONTROL case where the two options you mention will not be used.
Oh.
But in u-boot-tegra/master, both Seaboard and Ventana still set those options even though they have CONFIG_OF_CONTROL turned on. And it looks like board_init_uart_f() both uses those defines irrespective of CONFIG_OF_CONTROL /and/ is called solely based on CONFIG_BOARD_EARLY_INIT_F (not CONFIG_OF_CONTROL), which is also defined for Seaboard and Ventana.
I thought the upshot of this discussion was that there wasn't any need for any kind of pre-console stuff, either putc, puts/printf or whatever; instead, the console should simply be registered as early as possible based on the board/config's UART selection?
(and of course the DT parsed after that console was registered; no need for it before)