diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2011-11-07 16:16:54 +0000 |
|---|---|---|
| committer | Nicolas Pitre <nicolas.pitre@linaro.org> | 2011-11-10 17:32:54 -0500 |
| commit | eced83e4cee69d44d7f5b9ff09da0660a00406ab (patch) | |
| tree | 8403be0e4dbdca8d0d76fd55cedd80822ebaa15f | |
| parent | c94496d8ac970c73bc00413a5e9c775ca72c4a8e (diff) | |
ARM: LPAE: Add context switching support
With LPAE, TTBRx registers are 64-bit. The ASID is stored in TTBR0
rather than a separate Context ID register. This patch makes the
necessary changes to handle context switching on LPAE.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm/mm/context.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c index b0ee9ba3cfa..fcdb1017cdc 100644 --- a/arch/arm/mm/context.c +++ b/arch/arm/mm/context.c @@ -22,6 +22,21 @@ unsigned int cpu_last_asid = ASID_FIRST_VERSION; 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)); \ +} +#else +#define cpu_set_asid(asid) \ + asm(" mcr p15, 0, %0, c13, c0, 1\n" : : "r" (asid)) +#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 @@ -37,7 +52,7 @@ 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 */ - asm("mcr p15, 0, %0, c13, c0, 1\n" : : "r" (0)); + cpu_set_asid(0); isb(); local_flush_tlb_all(); if (icache_is_vivt_asid_tagged()) { @@ -99,7 +114,7 @@ static void reset_context(void *info) set_mm_context(mm, asid); /* set the new ASID */ - asm("mcr p15, 0, %0, c13, c0, 1\n" : : "r" (mm->context.id)); + cpu_set_asid(mm->context.id); isb(); } |