linux-stable.git/arch/arm/kernel/sleep.S, branch linux-3.1.y Linux kernel stable tree ARM: pm: allow suspend finisher to return error codes 2011-07-02T08:54:01+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-07-02T08:54:01+00:00 29cb3cd208dd0e4471bb80bec4facc49ceb199fa There are SoCs where attempting to enter a low power state is ignored, and the CPU continues executing instructions with all state preserved. It is over-complex at that point to disable the MMU just to call the resume path. Instead, allow the suspend finisher to return error codes to abort suspend in this circumstance, where the cpu_suspend internals will then unwind the saved state on the stack. Also omit the tlb flush as no changes to the page tables will have happened. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
There are SoCs where attempting to enter a low power state is ignored,
and the CPU continues executing instructions with all state preserved.
It is over-complex at that point to disable the MMU just to call the
resume path.

Instead, allow the suspend finisher to return error codes to abort
suspend in this circumstance, where the cpu_suspend internals will then
unwind the saved state on the stack.  Also omit the tlb flush as no
changes to the page tables will have happened.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: hide 1st and 2nd arguments to cpu_suspend from platform code 2011-06-24T08:54:39+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-22T16:41:48+00:00 2c74a0cefa463a7a483b07ba4d2ea8e4ec7b996c The first and second arguments shouldn't concern platform code, so hide them from each platforms caller. Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
The first and second arguments shouldn't concern platform code, so
hide them from each platforms caller.

Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: move cpu_init() call into core code 2011-06-24T07:48:43+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-21T15:32:58+00:00 14cd8fd574bce1cfbe510ccb1f73c7c1024d770f As we have core code dealing with CPU suspend/resume, we can re-initialize the CPUs exception banked registers via that code rather than having platforms deal with that level of detail. So, move the call to cpu_init() out of platform code into core code. Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
As we have core code dealing with CPU suspend/resume, we can
re-initialize the CPUs exception banked registers via that code rather
than having platforms deal with that level of detail.  So, move the
call to cpu_init() out of platform code into core code.

Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: convert cpu_suspend() to a normal function 2011-06-24T07:48:43+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T14:58:34+00:00 e8856a8797e76e6883ae81f8f9ecbb231cc535df cpu_suspend() has a weird calling method which makes it only possible to call from assembly code: it returns with a modified stack pointer to finish the suspend, but on resume, it 'returns' via a provided pointer. We can make cpu_suspend() appear to be a normal function merely by swapping the resume pointer argument and the link register. Do so, and update all callers to take account of this more traditional behaviour. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
cpu_suspend() has a weird calling method which makes it only possible to
call from assembly code: it returns with a modified stack pointer to
finish the suspend, but on resume, it 'returns' via a provided pointer.

We can make cpu_suspend() appear to be a normal function merely by
swapping the resume pointer argument and the link register.

Do so, and update all callers to take account of this more traditional
behaviour.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: rejig suspend follow-on function calling convention 2011-06-24T07:47:36+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T14:28:40+00:00 3799bbe57843d279008c9ec3406838966cad5f15 Save the suspend function pointer onto the stack for use when returning. Allocate r2 to pass an argument to the suspend function. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Save the suspend function pointer onto the stack for use when returning.
Allocate r2 to pass an argument to the suspend function.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: reallocate registers to avoid r2, r3 2011-06-24T07:47:32+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T14:25:11+00:00 8111eaa6d424ab3ba8a4d7a3148d4681ae5c6ae3 Avoid using r2 and r3 in the suspend code, allowing these to be passed further into the function as arguments. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Avoid using r2 and r3 in the suspend code, allowing these to be
passed further into the function as arguments.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: preserve r4 - r11 across a suspend 2011-06-24T07:47:29+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T14:04:14+00:00 5fa94c812c0001ac7c3d8868e956ec514734a352 Make cpu_suspend()..return function preserve r4 to r11 across a suspend cycle. This is in preparation of relieving platform support code from this task. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Make cpu_suspend()..return function preserve r4 to r11 across a suspend
cycle.  This is in preparation of relieving platform support code from
this task.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: extract common code from MULTI_CPU/!MULTI_CPU paths 2011-06-24T07:47:26+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T12:53:06+00:00 3fd431bd0cbc75a506b90b42619de3b04fe813a7 Very little code is different between these two paths now, so extract the common code. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Very little code is different between these two paths now, so extract
the common code.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: move return address (for cpu_resume) to top of stack 2011-06-24T07:47:23+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T12:45:34+00:00 2fefbcd58590cf33189c6178098e12b31b994b5f Move the return address for cpu_resume to the top of stack so that cpu_resume looks more like a normal function. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Move the return address for cpu_resume to the top of stack so that
cpu_resume looks more like a normal function.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: pm: make MULTI_CPU and !MULTI_CPU resume paths the same 2011-06-24T07:47:20+00:00 Russell King rmk+kernel@arm.linux.org.uk 2011-06-13T12:39:44+00:00 6b5f6ab0e1c33beaed828271f13c03ed02ee3c15 Eliminate the differences between MULTI_CPU and non-MULTI_CPU resume paths, making the saved structure identical irrespective of the way the kernel was configured. Acked-by: Frank Hofmann <frank.hofmann@tomtom.com> Tested-by: Kevin Hilman <khilman@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Eliminate the differences between MULTI_CPU and non-MULTI_CPU resume
paths, making the saved structure identical irrespective of the way
the kernel was configured.

Acked-by: Frank Hofmann <frank.hofmann@tomtom.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>