mips: Add CONFIG_MIPS_MACH_EARLY_INIT for very early mach init code
This patch adds the optional call to mips_mach_early_init() to start.S
at a very early stage. Its disabled per default. It can be used for
very early machine / platform specific init code. Its called very
early and at this stage the PC is allowed to differ from the linking
address (CONFIG_TEXT_BASE) as no absolute jump has been performed until
this call.
It will be used by thje Octeon platform.
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index eb00ee7..652e6a9 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -270,6 +270,15 @@
Normally this is CKSEG0. If the MIPS system needs to move this block
to some SRAM or ScratchPad RAM, adapt this option accordingly.
+config MIPS_MACH_EARLY_INIT
+ bool "Enable mach specific very early init code"
+ help
+ Use this to enable the call to mips_mach_early_init() very early
+ from start.S. This function can be used e.g. to do some very early
+ CPU / SoC intitialization or image copying. Its called very early
+ and at this stage the PC might not match the linking address
+ (CONFIG_TEXT_BASE) - no absolute jump done until this call.
+
config MIPS_CACHE_SETUP
bool "Allow generic start code to initialize and setup caches"
default n if SKIP_LOWLEVEL_INIT
diff --git a/arch/mips/cpu/start.S b/arch/mips/cpu/start.S
index e227717..d0c4122 100644
--- a/arch/mips/cpu/start.S
+++ b/arch/mips/cpu/start.S
@@ -236,6 +236,11 @@
# endif
#endif
+#ifdef CONFIG_MIPS_MACH_EARLY_INIT
+ bal mips_mach_early_init
+ nop
+#endif
+
#ifdef CONFIG_MIPS_CACHE_SETUP
/* Initialize caches... */
PTR_LA t9, mips_cache_reset