This is a note to let you know that I've just added the patch titled
sh: bios: Revive earlyprintk support
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sh-bios-revive-earlyprintk-support.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6c893fe043fedcc736e2fe58357a8875218d7e5b
Author: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Date: Thu Oct 19 11:46:43 2023 +0200
sh: bios: Revive earlyprintk support
[ Upstream commit 553f7ac78fbb41b2c93ab9b9d78e42274d27daa9 ]
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@xxxxxxxxx>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/c40972dfec3dcc6719808d5df388857360262878.1697708489.git.geert+renesas@xxxxxxxxx
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
index 71acd3d9b9e83..dfc784f897972 100644
--- a/arch/sh/Kconfig.debug
+++ b/arch/sh/Kconfig.debug
@@ -26,6 +26,17 @@ 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
