The SuperH BIOS earlyprintk code is protected by CONFIG_EARLY_PRINTK.
However, when this protection was added, it was missed that SuperH no
longer defines an EARLY_PRINTK config symbol since commit
e76fe57447e88916 ("sh: Remove old early serial console code V2"), so
BIOS earlyprintk can no longer be used.

Fix this by reviving the EARLY_PRINTK config symbol.

Fixes: d0380e6c3c0f6edb ("early_printk: consolidate random copies of identical code")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 arch/sh/Kconfig.debug | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
index c449e7c1b20ff5b5..8bcd6c1431a95be9 100644
--- a/arch/sh/Kconfig.debug
+++ b/arch/sh/Kconfig.debug
@@ -22,6 +22,17 @@ config STACK_DEBUG
 	  every function call and will therefore incur a major
 	  performance hit. Most users should say N.
 
+config EARLY_PRINTK
+	bool "Early printk"
+	depends on SH_STANDARD_BIOS
+	help
+	  Say Y here to redirect kernel printk messages to the serial port
+	  used by the SH-IPL bootloader, starting very early in the boot
+	  process and ending when the kernel's serial console is initialised.
+	  This option is only useful while porting the kernel to a new machine,
+	  when the kernel may crash or hang before the serial console is
+	  initialised.  If unsure, say N.
+
 config 4KSTACKS
 	bool "Use 4Kb for kernel stacks instead of 8Kb"
 	depends on DEBUG_KERNEL && (MMU || BROKEN) && !PAGE_SIZE_64KB
-- 
2.34.1

On Thu, 2023-10-19 at 11:46 +0200, Geert Uytterhoeven wrote:
> The SuperH BIOS earlyprintk code is protected by CONFIG_EARLY_PRINTK.
> However, when this protection was added, it was missed that SuperH no
> longer defines an EARLY_PRINTK config symbol since commit
> e76fe57447e88916 ("sh: Remove old early serial console code V2"), so
> BIOS earlyprintk can no longer be used.
> 
> Fix this by reviving the EARLY_PRINTK config symbol.
> 
> Fixes: d0380e6c3c0f6edb ("early_printk: consolidate random copies of identical code")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  arch/sh/Kconfig.debug | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
> index c449e7c1b20ff5b5..8bcd6c1431a95be9 100644
> --- a/arch/sh/Kconfig.debug
> +++ b/arch/sh/Kconfig.debug
> @@ -22,6 +22,17 @@ config STACK_DEBUG
>  	  every function call and will therefore incur a major
>  	  performance hit. Most users should say N.
>  
> +config EARLY_PRINTK
> +	bool "Early printk"
> +	depends on SH_STANDARD_BIOS
> +	help
> +	  Say Y here to redirect kernel printk messages to the serial port
> +	  used by the SH-IPL bootloader, starting very early in the boot
> +	  process and ending when the kernel's serial console is initialised.
> +	  This option is only useful while porting the kernel to a new machine,
> +	  when the kernel may crash or hang before the serial console is
> +	  initialised.  If unsure, say N.
> +
>  config 4KSTACKS
>  	bool "Use 4Kb for kernel stacks instead of 8Kb"
>  	depends on DEBUG_KERNEL && (MMU || BROKEN) && !PAGE_SIZE_64KB

Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
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