msm: hotplug: Change the pen variable in one place
Other WFI based hotplug implementations set the pen variable to
-1 in C code and do the appropriate flushing operations in one
location. They also don't try to invalidate the cache on a
spurious wakeup and report how many spurious wakeups there were.
Let's do the same in our code so that we can remove our
dependence on the dmac_{inv,flush}_range() functions (which are
no longer upstream) and easily report spurious wakeups to the
kernel logs.
This does delay the time we set the pen back to its default
value, but that doesn't actually matter because generic ARM
hotplug code already waits for a completion before continuing.
Change-Id: Ic36fbf744fe8abeda20ad9859a207b5e37c5e63c
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
diff --git a/arch/arm/mach-msm/hotplug.c b/arch/arm/mach-msm/hotplug.c
index 1a5fd5b..5cd5057 100644
--- a/arch/arm/mach-msm/hotplug.c
+++ b/arch/arm/mach-msm/hotplug.c
@@ -43,7 +43,7 @@
{
}
-static inline void platform_do_lowpower(unsigned int cpu)
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
{
/* Just enter wfi for now. TODO: Properly shut off the cpu. */
for (;;) {
@@ -53,9 +53,6 @@
/*
* OK, proper wakeup, we're done
*/
- pen_release = -1;
- dmac_flush_range((char *)&pen_release,
- (char *)&pen_release + sizeof(pen_release));
break;
}
@@ -67,9 +64,7 @@
* possible, since we are currently running incoherently, and
* therefore cannot safely call printk() or anything else
*/
- dmac_inv_range((char *)&pen_release,
- (char *)&pen_release + sizeof(pen_release));
- pr_debug("CPU%u: spurious wakeup call\n", cpu);
+ (*spurious)++;
}
}
@@ -85,6 +80,8 @@
*/
void platform_cpu_die(unsigned int cpu)
{
+ int spurious = 0;
+
if (unlikely(cpu != smp_processor_id())) {
pr_crit("%s: running on %u, should be %u\n",
__func__, smp_processor_id(), cpu);
@@ -95,10 +92,13 @@
* we're ready for shutdown now, so do it
*/
cpu_enter_lowpower();
- platform_do_lowpower(cpu);
+ platform_do_lowpower(cpu, &spurious);
pr_debug("CPU%u: %s: normal wakeup\n", cpu, __func__);
cpu_leave_lowpower();
+
+ if (spurious)
+ pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
}
int platform_cpu_disable(unsigned int cpu)