From patchwork Tue May 14 11:48:55 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jonathan Austin X-Patchwork-Id: 2565511 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) by patchwork1.kernel.org (Postfix) with ESMTP id B943B3FD85 for ; Tue, 14 May 2013 11:57:45 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UcDmn-0002BE-MK; Tue, 14 May 2013 11:52:58 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UcDkz-0003s4-E5; Tue, 14 May 2013 11:51:01 +0000 Received: from service87.mimecast.com ([91.220.42.44]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UcDkg-0003oF-2w for linux-arm-kernel@lists.infradead.org; Tue, 14 May 2013 11:50:44 +0000 Received: from cam-owa2.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Tue, 14 May 2013 12:50:22 +0100 Received: from e102895-lin.cambridge.arm.com ([10.1.255.212]) by cam-owa2.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Tue, 14 May 2013 12:50:22 +0100 From: Jonathan Austin To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 5/7] ARM: suspend: fix CPU suspend code for !CONFIG_MMU configurations Date: Tue, 14 May 2013 12:48:55 +0100 Message-Id: <1368532137-8871-6-git-send-email-jonathan.austin@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1368532137-8871-1-git-send-email-jonathan.austin@arm.com> References: <1368532137-8871-1-git-send-email-jonathan.austin@arm.com> MIME-Version: 1.0 X-OriginalArrivalTime: 14 May 2013 11:50:22.0275 (UTC) FILETIME=[36F7C930:01CE5099] X-MC-Unique: 113051412502201401 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130514_075042_381705_1208F0C3 X-CRM114-Status: GOOD ( 14.23 ) X-Spam-Score: -2.6 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [91.220.42.44 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Santosh Shilimkar , Lorenzo Pieralisi , will.deacon@arm.com, u.kleine-koenig@pengutronix.de X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Will Deacon The ARM CPU suspend code can be selected even for a !CONFIG_MMU configuration. The resulting kernel will not compile and, even if it did, would access undefined co-processor registers when executing. This patch fixes the v6 and v7 CPU suspend code for the nommu case. Signed-off-by: Will Deacon Tested-by: Jonathan Austin CC: Lorenzo Pieralisi CC: Santosh Shilimkar CC: Uwe Kleine-König --- arch/arm/kernel/suspend.c | 64 +++++++++++++++++++++++++-------------------- arch/arm/mm/proc-v6.S | 6 ++++- arch/arm/mm/proc-v7.S | 14 ++++++---- 3 files changed, 50 insertions(+), 34 deletions(-) diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c index c59c97e..38a5067 100644 --- a/arch/arm/kernel/suspend.c +++ b/arch/arm/kernel/suspend.c @@ -10,6 +10,42 @@ extern int __cpu_suspend(unsigned long, int (*)(unsigned long)); extern void cpu_resume_mmu(void); +#ifdef CONFIG_MMU +/* + * Hide the first two arguments to __cpu_suspend - these are an implementation + * detail which platform code shouldn't have to know about. + */ +int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) +{ + struct mm_struct *mm = current->active_mm; + int ret; + + if (!idmap_pgd) + return -EINVAL; + + /* + * Provide a temporary page table with an identity mapping for + * the MMU-enable code, required for resuming. On successful + * resume (indicated by a zero return code), we need to switch + * back to the correct page tables. + */ + ret = __cpu_suspend(arg, fn); + if (ret == 0) { + cpu_switch_mm(mm->pgd, mm); + local_flush_bp_all(); + local_flush_tlb_all(); + } + + return ret; +} +#else +int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) +{ + return __cpu_suspend(arg, fn); +} +#define idmap_pgd NULL +#endif + /* * This is called by __cpu_suspend() to save the state, and do whatever * flushing is required to ensure that when the CPU goes to sleep we have @@ -46,31 +82,3 @@ void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr) outer_clean_range(virt_to_phys(save_ptr), virt_to_phys(save_ptr) + sizeof(*save_ptr)); } - -/* - * Hide the first two arguments to __cpu_suspend - these are an implementation - * detail which platform code shouldn't have to know about. - */ -int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) -{ - struct mm_struct *mm = current->active_mm; - int ret; - - if (!idmap_pgd) - return -EINVAL; - - /* - * Provide a temporary page table with an identity mapping for - * the MMU-enable code, required for resuming. On successful - * resume (indicated by a zero return code), we need to switch - * back to the correct page tables. - */ - ret = __cpu_suspend(arg, fn); - if (ret == 0) { - cpu_switch_mm(mm->pgd, mm); - local_flush_bp_all(); - local_flush_tlb_all(); - } - - return ret; -} diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S index 919405e..2d1ef87 100644 --- a/arch/arm/mm/proc-v6.S +++ b/arch/arm/mm/proc-v6.S @@ -140,8 +140,10 @@ ENTRY(cpu_v6_set_pte_ext) ENTRY(cpu_v6_do_suspend) stmfd sp!, {r4 - r9, lr} mrc p15, 0, r4, c13, c0, 0 @ FCSE/PID +#ifdef CONFIG_MMU mrc p15, 0, r5, c3, c0, 0 @ Domain ID mrc p15, 0, r6, c2, c0, 1 @ Translation table base 1 +#endif mrc p15, 0, r7, c1, c0, 1 @ auxiliary control register mrc p15, 0, r8, c1, c0, 2 @ co-processor access control mrc p15, 0, r9, c1, c0, 0 @ control register @@ -158,14 +160,16 @@ ENTRY(cpu_v6_do_resume) mcr p15, 0, ip, c13, c0, 1 @ set reserved context ID ldmia r0, {r4 - r9} mcr p15, 0, r4, c13, c0, 0 @ FCSE/PID +#ifdef CONFIG_MMU mcr p15, 0, r5, c3, c0, 0 @ Domain ID ALT_SMP(orr r1, r1, #TTB_FLAGS_SMP) ALT_UP(orr r1, r1, #TTB_FLAGS_UP) mcr p15, 0, r1, c2, c0, 0 @ Translation table base 0 mcr p15, 0, r6, c2, c0, 1 @ Translation table base 1 + mcr p15, 0, ip, c2, c0, 2 @ TTB control register +#endif mcr p15, 0, r7, c1, c0, 1 @ auxiliary control register mcr p15, 0, r8, c1, c0, 2 @ co-processor access control - mcr p15, 0, ip, c2, c0, 2 @ TTB control register mcr p15, 0, ip, c7, c5, 4 @ ISB mov r0, r9 @ control register b cpu_resume_mmu diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 2c73a73..a851e34 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -98,9 +98,11 @@ ENTRY(cpu_v7_do_suspend) mrc p15, 0, r4, c13, c0, 0 @ FCSE/PID mrc p15, 0, r5, c13, c0, 3 @ User r/o thread ID stmia r0!, {r4 - r5} +#ifdef CONFIG_MMU mrc p15, 0, r6, c3, c0, 0 @ Domain ID mrc p15, 0, r7, c2, c0, 1 @ TTB 1 mrc p15, 0, r11, c2, c0, 2 @ TTB control register +#endif mrc p15, 0, r8, c1, c0, 0 @ Control register mrc p15, 0, r9, c1, c0, 1 @ Auxiliary control register mrc p15, 0, r10, c1, c0, 2 @ Co-processor access control @@ -110,13 +112,14 @@ ENDPROC(cpu_v7_do_suspend) ENTRY(cpu_v7_do_resume) mov ip, #0 - mcr p15, 0, ip, c8, c7, 0 @ invalidate TLBs mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache mcr p15, 0, ip, c13, c0, 1 @ set reserved context ID ldmia r0!, {r4 - r5} mcr p15, 0, r4, c13, c0, 0 @ FCSE/PID mcr p15, 0, r5, c13, c0, 3 @ User r/o thread ID ldmia r0, {r6 - r11} +#ifdef CONFIG_MMU + mcr p15, 0, ip, c8, c7, 0 @ invalidate TLBs mcr p15, 0, r6, c3, c0, 0 @ Domain ID #ifndef CONFIG_ARM_LPAE ALT_SMP(orr r1, r1, #TTB_FLAGS_SMP) @@ -125,14 +128,15 @@ ENTRY(cpu_v7_do_resume) mcr p15, 0, r1, c2, c0, 0 @ TTB 0 mcr p15, 0, r7, c2, c0, 1 @ TTB 1 mcr p15, 0, r11, c2, c0, 2 @ TTB control register - mrc p15, 0, r4, c1, c0, 1 @ Read Auxiliary control register - teq r4, r9 @ Is it already set? - mcrne p15, 0, r9, c1, c0, 1 @ No, so write it - mcr p15, 0, r10, c1, c0, 2 @ Co-processor access control ldr r4, =PRRR @ PRRR ldr r5, =NMRR @ NMRR mcr p15, 0, r4, c10, c2, 0 @ write PRRR mcr p15, 0, r5, c10, c2, 1 @ write NMRR +#endif /* CONFIG_MMU */ + mrc p15, 0, r4, c1, c0, 1 @ Read Auxiliary control register + teq r4, r9 @ Is it already set? + mcrne p15, 0, r9, c1, c0, 1 @ No, so write it + mcr p15, 0, r10, c1, c0, 2 @ Co-processor access control isb dsb mov r0, r8 @ control register