[PATCH v2 1/2] ARM: Add cpu_resume_arm() for firmwares that resume in ARM state
From: Stephen Boyd <hidden>
Date: 2015-06-02 19:13:10
Also in:
linux-arm-msm, lkml
Subsystem:
arm port, hibernation (aka software suspend, aka swsusp), the rest · Maintainers:
Russell King, "Rafael J. Wysocki", Linus Torvalds
Some platforms always enter the kernel in the ARM state even if the kernel is compiled for THUMB2. Add a small wrapper on top of cpu_resume() that switches into THUMB2 state. This fixes a problem reported by Kevin Hilman on next-20150601 where the ifc6410 fails to boot a THUMB2 kernel because the platform's firmware always enters the kernel in ARM mode from deep idle states. Reported-by: Kevin Hilman <redacted> Cc: Ard Biesheuvel <redacted> Cc: Lina Iyer <redacted> Signed-off-by: Stephen Boyd <redacted> --- arch/arm/include/asm/suspend.h | 1 + arch/arm/kernel/sleep.S | 7 +++++++ 2 files changed, 8 insertions(+)
diff --git a/arch/arm/include/asm/suspend.h b/arch/arm/include/asm/suspend.h
index cd20029bcd94..6c7182f32cef 100644
--- a/arch/arm/include/asm/suspend.h
+++ b/arch/arm/include/asm/suspend.h@@ -7,6 +7,7 @@ struct sleep_save_sp { }; extern void cpu_resume(void); +extern void cpu_resume_arm(void); extern int cpu_suspend(unsigned long, int (*)(unsigned long)); #endif
diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S
index 76bb3128e135..f37593567ef5 100644
--- a/arch/arm/kernel/sleep.S
+++ b/arch/arm/kernel/sleep.S@@ -118,6 +118,12 @@ ENDPROC(cpu_resume_after_mmu) .text .align + .arm +ENTRY(cpu_resume_arm) + THUMB( badr r9, 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(cpu_resume) ARM_BE8(setend be) @ ensure we are in BE mode #ifdef CONFIG_ARM_VIRT_EXT
@@ -149,6 +155,7 @@ THUMB( ldmia r0!, {r1, r2, r3} ) THUMB( mov sp, r2 ) THUMB( bx r3 ) ENDPROC(cpu_resume) +ENDPROC(cpu_resume_arm) .align 2 _sleep_save_sp:
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