diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2016-11-03 20:23:09 +0000 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2016-11-11 18:25:44 +0000 |
| commit | 623b476fc815464a0241ea7483da7b3580b7d8ac (patch) | |
| tree | 5bfda3f2e218b2dd884f28188def7ba73e8104ed /arch/arm64/kernel/sleep.S | |
| parent | 9bbd4c56b0b642f04396da378296e68096d5afca (diff) | |
arm64: move sp_el0 and tpidr_el1 into cpu_suspend_ctx
When returning from idle, we rely on the fact that thread_info lives at
the end of the kernel stack, and restore this by masking the saved stack
pointer. Subsequent patches will sever the relationship between the
stack and thread_info, and to cater for this we must save/restore sp_el0
explicitly, storing it in cpu_suspend_ctx.
As cpu_suspend_ctx must be doubleword aligned, this leaves us with an
extra slot in cpu_suspend_ctx. We can use this to save/restore tpidr_el1
in the same way, which simplifies the code, avoiding pointer chasing on
the restore path (as we no longer need to load thread_info::cpu followed
by the relevant slot in __per_cpu_offset based on this).
This patch stashes both registers in cpu_suspend_ctx.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: James Morse <james.morse@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/sleep.S')
| -rw-r--r-- | arch/arm64/kernel/sleep.S | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S index 1bec41b5fda3..df67652e46f0 100644 --- a/arch/arm64/kernel/sleep.S +++ b/arch/arm64/kernel/sleep.S @@ -125,9 +125,6 @@ ENTRY(_cpu_resume) /* load sp from context */ ldr x2, [x0, #CPU_CTX_SP] mov sp, x2 - /* save thread_info */ - and x2, x2, #~(THREAD_SIZE - 1) - msr sp_el0, x2 /* * cpu_do_resume expects x0 to contain context address pointer */ |