Hi Will, Hi All,
it appears that "ARM: proc: add definition of cpu_reset for
ARMv6 and ARMv7 cores" (f4daf06fc23b99df5ca5b3e892428b91e148cc52),
which was introduced for 3.1-rc1, causes a regression and that
kexec no longer works on ARM. The board that I am testing
on is a Renesas Mackerel which has an SH7372 (ARMv7) processor.
I have included the patch below for reference.
commit f4daf06fc23b99df5ca5b3e892428b91e148cc52
Author: Will Deacon <will.deacon at arm.com>
Date: Mon Jun 6 12:27:34 2011 +0100
ARM: proc: add definition of cpu_reset for ARMv6 and ARMv7 cores
This patch adds simple definitions of cpu_reset for ARMv6 and ARMv7
cores, which disable the MMU via the SCTLR.
Signed-off-by: Will Deacon <will.deacon at arm.com>
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S
index 5ec1543..aedf3c5 100644
--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S
@@ -56,6 +56,11 @@ ENTRY(cpu_v6_proc_fin)
*/
.align 5
ENTRY(cpu_v6_reset)
+ mrc p15, 0, r1, c1, c0, 0 @ ctrl register
+ bic r1, r1, #0x1 @ ...............m
+ mcr p15, 0, r1, c1, c0, 0 @ disable MMU
+ mov r1, #0
+ mcr p15, 0, r1, c7, c5, 4 @ ISB
mov pc, r0
/*
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 5932854..54d1a63 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -58,9 +58,16 @@ ENDPROC(cpu_v7_proc_fin)
* to what would be the reset vector.
*
* - loc - location to jump to for soft reset
+ *
+ * This code must be executed using a flat identity mapping with
+ * caches disabled.
*/
.align 5
ENTRY(cpu_v7_reset)
+ mrc p15, 0, r1, c1, c0, 0 @ ctrl register
+ bic r1, r1, #0x1 @ ...............m
+ mcr p15, 0, r1, c1, c0, 0 @ disable MMU
+ isb
mov pc, r0
ENDPROC(cpu_v7_reset)
