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authorH. Peter Anvin <hpa@linux.intel.com>2012-10-19 07:54:24 -0700
committerH. Peter Anvin <hpa@linux.intel.com>2012-10-19 07:55:09 -0700
commit4533d86270d7986e00594495dde9a109d6be27ae (patch)
treec2473cac653f7b98e5bd5e6475e63734be4b7644 /arch/arm/lib/delay.c
parent21c5e50e15b1abd797e62f18fd7f90b9cc004cbd (diff)
parent5bc66170dc486556a1e36fd384463536573f4b82 (diff)
Merge commit '5bc66170dc486556a1e36fd384463536573f4b82' into x86/urgent
From Borislav Petkov <bp@amd64.org>: Below is a RAS fix which reverts the addition of a sysfs attribute which we agreed is not needed, post-factum. And this should go in now because that sysfs attribute is going to end up in 3.7 otherwise and thus exposed to userspace; removing it then would be a lot harder. This is done as a merge rather than a simple patch/cherry-pick since the baseline for this patch was not in the previous x86/urgent. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/arm/lib/delay.c')
-rw-r--r--arch/arm/lib/delay.c34
1 files changed, 26 insertions, 8 deletions
diff --git a/arch/arm/lib/delay.c b/arch/arm/lib/delay.c
index d6dacc69254..9d0a30032d7 100644
--- a/arch/arm/lib/delay.c
+++ b/arch/arm/lib/delay.c
@@ -34,7 +34,18 @@ struct arm_delay_ops arm_delay_ops = {
.udelay = __loop_udelay,
};
-#ifdef ARCH_HAS_READ_CURRENT_TIMER
+static const struct delay_timer *delay_timer;
+static bool delay_calibrated;
+
+int read_current_timer(unsigned long *timer_val)
+{
+ if (!delay_timer)
+ return -ENXIO;
+
+ *timer_val = delay_timer->read_current_timer();
+ return 0;
+}
+
static void __timer_delay(unsigned long cycles)
{
cycles_t start = get_cycles();
@@ -55,17 +66,24 @@ static void __timer_udelay(unsigned long usecs)
__timer_const_udelay(usecs * UDELAY_MULT);
}
-void __init init_current_timer_delay(unsigned long freq)
+void __init register_current_timer_delay(const struct delay_timer *timer)
{
- pr_info("Switching to timer-based delay loop\n");
- lpj_fine = freq / HZ;
- arm_delay_ops.delay = __timer_delay;
- arm_delay_ops.const_udelay = __timer_const_udelay;
- arm_delay_ops.udelay = __timer_udelay;
+ if (!delay_calibrated) {
+ pr_info("Switching to timer-based delay loop\n");
+ delay_timer = timer;
+ lpj_fine = timer->freq / HZ;
+ loops_per_jiffy = lpj_fine;
+ arm_delay_ops.delay = __timer_delay;
+ arm_delay_ops.const_udelay = __timer_const_udelay;
+ arm_delay_ops.udelay = __timer_udelay;
+ delay_calibrated = true;
+ } else {
+ pr_info("Ignoring duplicate/late registration of read_current_timer delay\n");
+ }
}
unsigned long __cpuinit calibrate_delay_is_known(void)
{
+ delay_calibrated = true;
return lpj_fine;
}
-#endif