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Subject[PATCH] ARM: OMAP4: sleep/smp: switch CPU to BE if compiled for BE
Date
From: Victor Kamensky <victor.kamensky@linaro.org>

If kernel operates in BE mode on device that has LE bootloader/ROM code,
we need to switch CPU to operate in BE mode before it will start to
access BE data. Generic secondary_startup function that is called from
OMAP specific secondary startup code will do the switch, but we need
to do it earlier because OMAP's secondary_startup code works with BE data.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
---
This is a part of RFC series [1].
Based on v3.13-rc8.

[1] http://www.spinics.net/lists/linux-omap/msg99927.html

arch/arm/mach-omap2/omap-headsmp.S | 13 +++++++++++++
arch/arm/mach-omap2/sleep44xx.S | 6 ++++++
2 files changed, 19 insertions(+)

diff --git a/arch/arm/mach-omap2/omap-headsmp.S b/arch/arm/mach-omap2/omap-headsmp.S
index 75e9295..75c98d4 100644
--- a/arch/arm/mach-omap2/omap-headsmp.S
+++ b/arch/arm/mach-omap2/omap-headsmp.S
@@ -17,6 +17,7 @@

#include <linux/linkage.h>
#include <linux/init.h>
+#include <asm/assembler.h>

#include "omap44xx.h"

@@ -58,6 +59,12 @@ hold: ldr r12,=0x103
bne hold

/*
+ * ROM code operates in little endian mode, when we get control we
+ * need to switch it back to big endian mode.
+ */
+ARM_BE8(setend be)
+
+ /*
* we've been released from the wait loop,secondary_stack
* should now contain the SVC stack for this core
*/
@@ -75,6 +82,12 @@ hold_2: ldr r12,=0x103
bne hold_2

/*
+ * ROM code operates in little endian mode, when we get control we
+ * need to switch it back to big endian mode.
+ */
+ARM_BE8(setend be)
+
+ /*
* GIC distributor control register has changed between
* CortexA9 r1pX and r2pX. The Control Register secure
* banked version is now composed of 2 bits:
diff --git a/arch/arm/mach-omap2/sleep44xx.S b/arch/arm/mach-omap2/sleep44xx.S
index 9086ce0..e556c8b 100644
--- a/arch/arm/mach-omap2/sleep44xx.S
+++ b/arch/arm/mach-omap2/sleep44xx.S
@@ -249,6 +249,12 @@ ENDPROC(omap4_finish_suspend)
*/
ENTRY(omap4_cpu_resume)
/*
+ * ROM code operates in little endian mode, when we get control we
+ * need to switch it back to big endian mode.
+ */
+ARM_BE8(setend be)
+
+ /*
* Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
* OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
* init and for CPU1, a secure PPA API provided. CPU0 must be ON
--
1.7.9.5


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