ARM: PSCI: use only r0 and r3 in psci_get_cpu_stack_top()

For psci_get_cpu_stack_top() to be usable in C code, it must adhere to
the ARM calling conventions. Since it could be called when the stack
is still unavailable, and the entry code to linux also expects r1 and
r2 to remain unchanged, stick to r0 and r3.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
This commit is contained in:
Chen-Yu Tsai 2016-06-07 10:54:24 +08:00 committed by Hans de Goede
parent 3da9536e8f
commit dae08d2281

View file

@ -196,15 +196,15 @@ ENDPROC(psci_cpu_off_common)
@ expects CPU ID in r0 and returns stack top in r0
ENTRY(psci_get_cpu_stack_top)
mov r5, #0x400 @ 1kB of stack per CPU
mul r0, r0, r5
mov r3, #0x400 @ 1kB of stack per CPU
mul r0, r0, r3
ldr r5, =psci_text_end @ end of monitor text
add r5, r5, #0x2000 @ Skip two pages
lsr r5, r5, #12 @ Align to start of page
lsl r5, r5, #12
sub r5, r5, #4 @ reserve 1 word for target PC
sub r0, r5, r0 @ here's our stack!
ldr r3, =psci_text_end @ end of monitor text
add r3, r3, #0x2000 @ Skip two pages
lsr r3, r3, #12 @ Align to start of page
lsl r3, r3, #12
sub r3, r3, #4 @ reserve 1 word for target PC
sub r0, r3, r0 @ here's our stack!
bx lr
ENDPROC(psci_get_cpu_stack_top)