[PATCH u-boot v2019.04-aspeed-openbmc v3 2/3] arm/mach-aspeed: Add support for CONFIG_DRAM_UART_TO_UART1

[Zev Weiss]

On Thu, May 19, 2022 at 08:07:18AM PDT, Patrick Rudolph wrote:
> Update the Kconfig and allow a board to use CONFIG_DRAM_UART_TO_UART1.
> The platform code already uses this Kconfig symbol, but it always
> evaluated to false.
> This is required on IBM/Genesis3 as it uses RDX1/TDX1 as debug uart.
> 
> Signed-off-by: Patrick Rudolph <patrick.rudolph at 9elements.com>
> Reviewed-by: Joel Stanley <joel at jms.id.au>
> ---
>  arch/arm/mach-aspeed/ast2500/Kconfig | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/arch/arm/mach-aspeed/ast2500/Kconfig b/arch/arm/mach-aspeed/ast2500/Kconfig
> index 4f992f442d..e7ff00cdba 100644
> --- a/arch/arm/mach-aspeed/ast2500/Kconfig
> +++ b/arch/arm/mach-aspeed/ast2500/Kconfig
> @@ -17,6 +17,12 @@ config TARGET_EVB_AST2500
>  	  20 pin JTAG, pinouts for 14 I2Cs, 3 SPIs and eSPI, 8 PWMs.
>  endchoice
>  
> +config DRAM_UART_TO_UART1
> +	bool
> +	prompt "Route debug UART to UART1"
> +	help
> +	  Route debug UART to TXD1/RXD1 pins.
> +

Given that the debug UART is now disabled by default and only available 
via a combination of CONFIG_ASPEED_ALLOW_DANGEROUS_BACKDOORS=y and 
CONFIG_ASPEED_ENABLE_DEBUG_UART=y, I'd suggest moving this to 
arch/arm/mach-aspeed/Kconfig in the ASPEED_ALLOW_DANGEROUS_BACKDOORS 
'if' block, perhaps in a nested 'if' block conditional on 
ASPEED_ENABLE_DEBUG_UART.

Also, I realize that name comes from previously existing code in 
platform.S, but it's not exactly the clearest, most descriptive name in 
the world (it's the debug UART, what's it go to do with DRAM?).  If 
we're going to promote it to a Kconfig option I think it'd be nice to 
improve the naming somewhat, perhaps just s/DRAM/DEBUG/.

>  source "board/aspeed/evb_ast2500/Kconfig"
>  
>  endif
> -- 
> 2.35.3
>