[PATCH 3.2 145/164] ARM: 8216/1: xscale: correct auxiliary register in suspend/resume

From: Ben Hutchings
Date: Fri Dec 12 2014 - 01:43:01 EST


3.2.65-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Dmitry Eremin-Solenikov <dbaryshkov@xxxxxxxxx>

commit ef59a20ba375aeb97b3150a118318884743452a8 upstream.

According to the manuals I have, XScale auxiliary register should be
reached with opc_2 = 1 instead of crn = 1. cpu_xscale_proc_init
correctly uses c1, c0, 1 arguments, but cpu_xscale_do_suspend and
cpu_xscale_do_resume use c1, c1, 0. Correct suspend/resume functions to
also use c1, c0, 1.

The issue was primarily noticed thanks to qemu reporing "unsupported
instruction" on the pxa suspend path. Confirmed in PXA210/250 and PXA255
XScale Core manuals and in PXA270 and PXA320 Developers Guides.

Harware tested by me on tosa (pxa255). Robert confirmed on pxa270 board.

Tested-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@xxxxxxxxx>
Acked-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/arm/mm/proc-xscale.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/arm/mm/proc-xscale.S
+++ b/arch/arm/mm/proc-xscale.S
@@ -528,7 +528,7 @@ ENTRY(cpu_xscale_do_suspend)
mrc p15, 0, r5, c15, c1, 0 @ CP access reg
mrc p15, 0, r6, c13, c0, 0 @ PID
mrc p15, 0, r7, c3, c0, 0 @ domain ID
- mrc p15, 0, r8, c1, c1, 0 @ auxiliary control reg
+ mrc p15, 0, r8, c1, c0, 1 @ auxiliary control reg
mrc p15, 0, r9, c1, c0, 0 @ control reg
bic r4, r4, #2 @ clear frequency change bit
stmia r0, {r4 - r9} @ store cp regs
@@ -545,7 +545,7 @@ ENTRY(cpu_xscale_do_resume)
mcr p15, 0, r6, c13, c0, 0 @ PID
mcr p15, 0, r7, c3, c0, 0 @ domain ID
mcr p15, 0, r1, c2, c0, 0 @ translation table base addr
- mcr p15, 0, r8, c1, c1, 0 @ auxiliary control reg
+ mcr p15, 0, r8, c1, c0, 1 @ auxiliary control reg
mov r0, r9 @ control register
b cpu_resume_mmu
ENDPROC(cpu_xscale_do_resume)

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/