From aa1aadc3305c4917c39f0291613a5ec81dd4c73b Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 23 Feb 2012 13:51:38 +0000 Subject: ARM: suspend: fix CPU suspend code for !CONFIG_MMU configurations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 (commit_signer:1/3=33%) CC: Santosh Shilimkar (commit_signer:1/3=33%) 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 c59c97ea8268..38a50676213b 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 919405e20b80..2d1ef87328a1 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 2c73a7301ff7..a851e3433afe 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 -- cgit