Subject: [PATCH 1/2] ARM: Add a secondary_startup that assumes ARM mode

From: [email-masked] (Stephen Boyd)
Date: Wed, 21 Jan 2015 11:48:17 -0800

Some platforms always enter the kernel in ARM mode even if the
kernel is compiled for THUMB2. Add a small wrapper on top of
secondary_startup() that switches into THUMB2 mode.

Signed-off-by: Stephen Boyd <[email-masked]>
---
 arch/arm/kernel/head.S | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 664eee8c4a26..22bb6d54e90d 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -346,6 +346,12 @@ __turn_mmu_on_loc:
 
 #if defined(CONFIG_SMP)
 	.text
+ENTRY(secondary_startup_arm)
+	.arm
+ THUMB(	adr	r9, BSYM(1f)	)	@ Kernel is entered in ARM.
+ THUMB(	bx	r9		)	@ If this is a Thumb-2 kernel,
+ THUMB(	.thumb			)	@ switch to Thumb now.
+ THUMB(1:			)
 ENTRY(secondary_startup)
 	/*
 	 * Common entry point for secondary CPUs.
@@ -385,6 +391,7 @@ ENTRY(secondary_startup)
  THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)
  THUMB(	ret	r12				)
 ENDPROC(secondary_startup)
+ENDPROC(secondary_startup_arm)
 
 	/*
 	 * r6  = &secondary_data
-- 
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