From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: [PATCH v2 1/2] ARM: Add cpu_resume_arm() for firmwares that resume in ARM state Date: Tue, 2 Jun 2015 12:12:57 -0700 Message-ID: <1433272378-8470-2-git-send-email-sboyd@codeaurora.org> References: <1433272378-8470-1-git-send-email-sboyd@codeaurora.org> Return-path: In-Reply-To: <1433272378-8470-1-git-send-email-sboyd@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org To: Russell King Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Kevin Hilman , Andy Gross , Kumar Gala , Ard Biesheuvel , Lina Iyer List-Id: linux-arm-msm@vger.kernel.org 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 Cc: Ard Biesheuvel Cc: Lina Iyer Signed-off-by: Stephen Boyd --- 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: -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project From mboxrd@z Thu Jan 1 00:00:00 1970 From: sboyd@codeaurora.org (Stephen Boyd) Date: Tue, 2 Jun 2015 12:12:57 -0700 Subject: [PATCH v2 1/2] ARM: Add cpu_resume_arm() for firmwares that resume in ARM state In-Reply-To: <1433272378-8470-1-git-send-email-sboyd@codeaurora.org> References: <1433272378-8470-1-git-send-email-sboyd@codeaurora.org> Message-ID: <1433272378-8470-2-git-send-email-sboyd@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Cc: Ard Biesheuvel Cc: Lina Iyer Signed-off-by: Stephen Boyd --- 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: -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project