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ARM: pm: CPU specific code should not overwrite r1 (v:p offset)
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r1 stores the v:p offset from the CPU invariant resume code, and is
expected to be preserved by the CPU specific code.  Overwriting it is
not a good idea.

We've managed to get away with it on sa1100 platforms because most
happen to have PHYS_OFFSET == PAGE_OFFSET, but that may not be the
case depending on kernel configuration.  So fix this latent bug.

This fixes xsc3 as well which was saving and restoring this register
independently.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King committed Aug 28, 2011
1 parent 0f81bb6 commit 6f354e5
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Showing 2 changed files with 8 additions and 8 deletions.
10 changes: 5 additions & 5 deletions arch/arm/mm/proc-sa1100.S
Original file line number Diff line number Diff line change
Expand Up @@ -182,11 +182,11 @@ ENDPROC(cpu_sa1100_do_suspend)

ENTRY(cpu_sa1100_do_resume)
ldmia r0, {r4 - r7} @ load cp regs
mov r1, #0
mcr p15, 0, r1, c8, c7, 0 @ flush I+D TLBs
mcr p15, 0, r1, c7, c7, 0 @ flush I&D cache
mcr p15, 0, r1, c9, c0, 0 @ invalidate RB
mcr p15, 0, r1, c9, c0, 5 @ allow user space to use RB
mov ip, #0
mcr p15, 0, ip, c8, c7, 0 @ flush I+D TLBs
mcr p15, 0, ip, c7, c7, 0 @ flush I&D cache
mcr p15, 0, ip, c9, c0, 0 @ invalidate RB
mcr p15, 0, ip, c9, c0, 5 @ allow user space to use RB

mcr p15, 0, r4, c3, c0, 0 @ domain ID
mcr p15, 0, r5, c2, c0, 0 @ translation table base addr
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6 changes: 3 additions & 3 deletions arch/arm/mm/proc-xsc3.S
Original file line number Diff line number Diff line change
Expand Up @@ -406,7 +406,7 @@ ENTRY(cpu_xsc3_set_pte_ext)
.align

.globl cpu_xsc3_suspend_size
.equ cpu_xsc3_suspend_size, 4 * 8
.equ cpu_xsc3_suspend_size, 4 * 7
#ifdef CONFIG_PM_SLEEP
ENTRY(cpu_xsc3_do_suspend)
stmfd sp!, {r4 - r10, lr}
Expand All @@ -418,12 +418,12 @@ ENTRY(cpu_xsc3_do_suspend)
mrc p15, 0, r9, c1, c0, 1 @ auxiliary control reg
mrc p15, 0, r10, c1, c0, 0 @ control reg
bic r4, r4, #2 @ clear frequency change bit
stmia r0, {r1, r4 - r10} @ store v:p offset + cp regs
stmia r0, {r4 - r10} @ store cp regs
ldmia sp!, {r4 - r10, pc}
ENDPROC(cpu_xsc3_do_suspend)

ENTRY(cpu_xsc3_do_resume)
ldmia r0, {r1, r4 - r10} @ load v:p offset + cp regs
ldmia r0, {r4 - r10} @ load cp regs
mov ip, #0
mcr p15, 0, ip, c7, c7, 0 @ invalidate I & D caches, BTB
mcr p15, 0, ip, c7, c10, 4 @ drain write (&fill) buffer
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