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-rw-r--r--arch/arm/mm/context.c45
-rw-r--r--arch/arm/mm/proc-v7-2level.S10
2 files changed, 31 insertions, 24 deletions
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index ee9bb363d606..aaa291fc072e 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -23,25 +23,37 @@ DEFINE_PER_CPU(struct mm_struct *, current_mm);
#endif
#ifdef CONFIG_ARM_LPAE
-#define cpu_set_asid(asid) { \
- unsigned long ttbl, ttbh; \
- asm volatile( \
- " mrrc p15, 0, %0, %1, c2 @ read TTBR0\n" \
- " mov %1, %2, lsl #(48 - 32) @ set ASID\n" \
- " mcrr p15, 0, %0, %1, c2 @ set TTBR0\n" \
- : "=&r" (ttbl), "=&r" (ttbh) \
- : "r" (asid & ~ASID_MASK)); \
+static void cpu_set_reserved_ttbr0(void)
+{
+ unsigned long ttbl = __pa(swapper_pg_dir);
+ unsigned long ttbh = 0;
+
+ /*
+ * Set TTBR0 to swapper_pg_dir which contains only global entries. The
+ * ASID is set to 0.
+ */
+ asm volatile(
+ " mcrr p15, 0, %0, %1, c2 @ set TTBR0\n"
+ :
+ : "r" (ttbl), "r" (ttbh));
+ isb();
}
#else
-#define cpu_set_asid(asid) \
- asm(" mcr p15, 0, %0, c13, c0, 1\n" : : "r" (asid))
+static void cpu_set_reserved_ttbr0(void)
+{
+ u32 ttb;
+ /* Copy TTBR1 into TTBR0 */
+ asm volatile(
+ " mrc p15, 0, %0, c2, c0, 1 @ read TTBR1\n"
+ " mcr p15, 0, %0, c2, c0, 0 @ set TTBR0\n"
+ : "=r" (ttb));
+ isb();
+}
#endif
/*
* We fork()ed a process, and we need a new context for the child
- * to run in. We reserve version 0 for initial tasks so we will
- * always allocate an ASID. The ASID 0 is reserved for the TTBR
- * register changing sequence.
+ * to run in.
*/
void __init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
@@ -51,9 +63,7 @@ void __init_new_context(struct task_struct *tsk, struct mm_struct *mm)
static void flush_context(void)
{
- /* set the reserved ASID before flushing the TLB */
- cpu_set_asid(0);
- isb();
+ cpu_set_reserved_ttbr0();
local_flush_tlb_all();
if (icache_is_vivt_asid_tagged()) {
__flush_icache_all();
@@ -114,8 +124,7 @@ static void reset_context(void *info)
set_mm_context(mm, asid);
/* set the new ASID */
- cpu_set_asid(mm->context.id);
- isb();
+ cpu_switch_mm(mm->pgd, mm);
}
#else
diff --git a/arch/arm/mm/proc-v7-2level.S b/arch/arm/mm/proc-v7-2level.S
index 3a4b3e7b888c..72270482a922 100644
--- a/arch/arm/mm/proc-v7-2level.S
+++ b/arch/arm/mm/proc-v7-2level.S
@@ -46,18 +46,16 @@ ENTRY(cpu_v7_switch_mm)
#ifdef CONFIG_ARM_ERRATA_430973
mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB
#endif
-#ifdef CONFIG_ARM_ERRATA_754322
- dsb
-#endif
- mcr p15, 0, r2, c13, c0, 1 @ set reserved context ID
- isb
-1: mcr p15, 0, r0, c2, c0, 0 @ set TTB 0
+ mrc p15, 0, r2, c2, c0, 1 @ load TTB 1
+ mcr p15, 0, r2, c2, c0, 0 @ into TTB 0
isb
#ifdef CONFIG_ARM_ERRATA_754322
dsb
#endif
mcr p15, 0, r1, c13, c0, 1 @ set context ID
isb
+ mcr p15, 0, r0, c2, c0, 0 @ set TTB 0
+ isb
#endif
mov pc, lr
ENDPROC(cpu_v7_switch_mm)