aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/mach-shmobile/setup-rcar-gen2.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-shmobile/setup-rcar-gen2.c')
-rw-r--r--arch/arm/mach-shmobile/setup-rcar-gen2.c21
1 files changed, 16 insertions, 5 deletions
diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
index 5734c24bf6c7..b6275ab6085c 100644
--- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -78,12 +78,23 @@ void __init rcar_gen2_timer_init(void)
/* Remap "armgcnt address map" space */
base = ioremap(0xe6080000, PAGE_SIZE);
- /* Update registers with correct frequency */
- iowrite32(freq, base + CNTFID0);
- asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
+ /*
+ * Update the timer if it is either not running, or is not at the
+ * right frequency. The timer is only configurable in secure mode
+ * so this avoids an abort if the loader started the timer and
+ * entered the kernel in non-secure mode.
+ */
+
+ if ((ioread32(base + CNTCR) & 1) == 0 ||
+ ioread32(base + CNTFID0) != freq) {
+ /* Update registers with correct frequency */
+ iowrite32(freq, base + CNTFID0);
+ asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
+
+ /* make sure arch timer is started by setting bit 0 of CNTCR */
+ iowrite32(1, base + CNTCR);
+ }
- /* make sure arch timer is started by setting bit 0 of CNTCR */
- iowrite32(1, base + CNTCR);
iounmap(base);
#endif /* CONFIG_ARM_ARCH_TIMER */