[PATCH] serial: stm32: restrict _debug_uart_init() usage

[Patrick DELAUNAY]

Hi,

On 1/30/25 12:57, Patrice Chotard wrote:
> Since commit 948da7773e34 ("arm: Add new config option ARCH_VERY_EARLY_INIT")
> debug_uart_init() is called respectively in crt0.S and crt0_64.S.
> That means that _debug_uart_init() is called for all STM32MP platforms
> even for those which doesn't support SPL_BUILD.
>
> So restrict _debug_uart_init() execution for platforms which can have
> SPL_BUILD enabled (STM32MP1 platform only).
>
> It's more needed to call debug_uart_init() in stm32mp1/cpu.c.
>
> Signed-off-by: Patrice Chotard <patrice.chotard at foss.st.com>
> ---
>
>   arch/arm/mach-stm32mp/stm32mp1/cpu.c |  2 --
>   drivers/serial/serial_stm32.c        | 18 ++++++++++++------
>   2 files changed, 12 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm/mach-stm32mp/stm32mp1/cpu.c b/arch/arm/mach-stm32mp/stm32mp1/cpu.c
> index cb1b84c9af9..bc410128479 100644
> --- a/arch/arm/mach-stm32mp/stm32mp1/cpu.c
> +++ b/arch/arm/mach-stm32mp/stm32mp1/cpu.c
> @@ -138,8 +138,6 @@ int mach_cpu_init(void)
>   	if (IS_ENABLED(CONFIG_CMD_STM32PROG_SERIAL) &&
>   	    (boot_mode & TAMP_BOOT_DEVICE_MASK) == BOOT_SERIAL_UART)
>   		gd->flags |= GD_FLG_SILENT | GD_FLG_DISABLE_CONSOLE;
> -	else if (IS_ENABLED(CONFIG_DEBUG_UART) && IS_ENABLED(CONFIG_XPL_BUILD))
> -		debug_uart_init();
>   
>   	return 0;
>   }
> diff --git a/drivers/serial/serial_stm32.c b/drivers/serial/serial_stm32.c
> index 1ee58142b3f..1675a9cb9d1 100644
> --- a/drivers/serial/serial_stm32.c
> +++ b/drivers/serial/serial_stm32.c
> @@ -299,13 +299,19 @@ static inline struct stm32_uart_info *_debug_uart_info(void)
>   
>   static inline void _debug_uart_init(void)
>   {
> -	void __iomem *base = (void __iomem *)CONFIG_VAL(DEBUG_UART_BASE);
> -	struct stm32_uart_info *uart_info = _debug_uart_info();
> +	void __maybe_unused __iomem *base = (void __iomem *)CONFIG_VAL(DEBUG_UART_BASE);
> +	struct stm32_uart_info *uart_info __maybe_unused = _debug_uart_info();
>   
> -	_stm32_serial_init(base, uart_info);
> -	_stm32_serial_setbrg(base, uart_info,
> -			     CONFIG_DEBUG_UART_CLOCK,
> -			     CONFIG_BAUDRATE);
> +	/*
> +	 * debug_uart_init() is only usable when SPL_BUILD is enabled
> +	 * (STM32MP1 case only)
> +	 */
> +	if (IS_ENABLED(CONFIG_DEBUG_UART) && IS_ENABLED(CONFIG_SPL_BUILD)) {
> +		_stm32_serial_init(base, uart_info);
> +		_stm32_serial_setbrg(base, uart_info,
> +				     CONFIG_DEBUG_UART_CLOCK,
> +				     CONFIG_BAUDRATE);
> +	}
>   }
>   
>   static inline void _debug_uart_putc(int c)


Reviewed-by: Patrick Delaunay <patrick.delaunay at foss.st.com>

Thanks
Patrick