arm: Add bootblock_mainboard_early_init() for pre-console initialization

On most platforms, enabling the console and exception handlers are
amongst the very first things you want to do, as they help you see
what's going on and debug errors in other early init code. However, most
ARM boards require some small amount of board-specific initialization
(pinmuxing, maybe clocks) to get the UART running, which is why
bootblock_mainboard_init() (and with it almost all of the actual
bootblock code) always had to run before console initialization for now.

This patch introduces an explicit bootblock_mainboard_early_init() hook
for only that part of initialization that absolutely needs to run before
console output. The other two hooks for SoC and mainboard are moved
below console_init(). This model has already proven its worth before in
the tegra124 and tegra132 custom bootblocks.

BRANCH=None
BUG=chrome-os-partner:32123
TEST=Booted on Pinky. Compiled for Daisy, Storm and Ryu.

Change-Id: I510c58189faf0c08c740bcc3b5a654f81f892464
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: f58e84a2fc1c9951e9c4c65cdec1dbeb6a20d597
Original-Change-Id: I4257b5a8807595140e8c973ca04e68ea8630bf9a
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/231941
Reviewed-on: http://review.coreboot.org/9603
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

3 files changed, 11 insertions, 4 deletions

diff --git a/src/arch/arm/armv4/bootblock_simple.c b/src/arch/arm/armv4/bootblock_simple.c
index 9e399a9b7c..26646eebf5 100644
--- a/src/arch/arm/armv4/bootblock_simple.c
+++ b/src/arch/arm/armv4/bootblock_simple.c
@@ -26,18 +26,21 @@
 #include <console/console.h>
 #include <program_loading.h>
 
+__attribute__((weak)) void bootblock_mainboard_early_init(void) { /* no-op */ }
 __attribute__((weak)) void bootblock_soc_init(void) { /* do nothing */ }
 __attribute__((weak)) void bootblock_mainboard_init(void) { /* do nothing */ }
 
 void main(void)
 {
-	bootblock_soc_init();
-	bootblock_mainboard_init();
+	bootblock_mainboard_early_init();
 
 	if (CONFIG_BOOTBLOCK_CONSOLE) {
 		console_init();
 		exception_init();
 	}
 
+	bootblock_soc_init();
+	bootblock_mainboard_init();
+
 	run_romstage();
 }
diff --git a/src/arch/arm/armv7/bootblock_simple.c b/src/arch/arm/armv7/bootblock_simple.c
index 450e5b437b..564db5b80a 100644
--- a/src/arch/arm/armv7/bootblock_simple.c
+++ b/src/arch/arm/armv7/bootblock_simple.c
@@ -27,18 +27,21 @@
 #include <program_loading.h>
 #include <smp/node.h>
 
+__attribute__((weak)) void bootblock_mainboard_early_init(void) { /* no-op */ }
 __attribute__((weak)) void bootblock_soc_init(void) { /* do nothing */ }
 __attribute__((weak)) void bootblock_mainboard_init(void) { /* do nothing */ }
 
 void main(void)
 {
-	bootblock_soc_init();
-	bootblock_mainboard_init();
+	bootblock_mainboard_early_init();
 
 #if CONFIG_BOOTBLOCK_CONSOLE
 	console_init();
 	exception_init();
 #endif
 
+	bootblock_soc_init();
+	bootblock_mainboard_init();
+
 	run_romstage();
 }
diff --git a/src/arch/arm/include/bootblock_common.h b/src/arch/arm/include/bootblock_common.h
index 413a206177..06312928da 100644
--- a/src/arch/arm/include/bootblock_common.h
+++ b/src/arch/arm/include/bootblock_common.h
@@ -21,6 +21,7 @@
 #define __ARCH_BOOTBLOCK_COMMON_H
 
 /* These are defined as weak no-ops that can be overridden by mainboard/SoC. */
+void bootblock_mainboard_early_init(void);
 void bootblock_mainboard_init(void);
 void bootblock_soc_init(void);