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-rw-r--r--arch/arm/mach-omap2/omap-smp.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c
index ee83808de0ff..c1bf3ef0ba02 100644
--- a/arch/arm/mach-omap2/omap-smp.c
+++ b/arch/arm/mach-omap2/omap-smp.c
@@ -28,6 +28,8 @@
#include "common.h"
+#include "clockdomain.h"
+
/* SCU base address */
static void __iomem *scu_base;
@@ -68,6 +70,8 @@ void __cpuinit platform_secondary_init(unsigned int cpu)
int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
{
+ static struct clockdomain *cpu1_clkdm;
+ static bool booted;
/*
* Set synchronisation state between this boot processor
* and the secondary one
@@ -83,6 +87,29 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
omap_modify_auxcoreboot0(0x200, 0xfffffdff);
flush_cache_all();
smp_wmb();
+
+ if (!cpu1_clkdm)
+ cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
+
+ /*
+ * The SGI(Software Generated Interrupts) are not wakeup capable
+ * from low power states. This is known limitation on OMAP4 and
+ * needs to be worked around by using software forced clockdomain
+ * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
+ * software force wakeup. The clockdomain is then put back to
+ * hardware supervised mode.
+ * More details can be found in OMAP4430 TRM - Version J
+ * Section :
+ * 4.3.4.2 Power States of CPU0 and CPU1
+ */
+ if (booted) {
+ clkdm_wakeup(cpu1_clkdm);
+ clkdm_allow_idle(cpu1_clkdm);
+ } else {
+ dsb_sev();
+ booted = true;
+ }
+
gic_raise_softirq(cpumask_of(cpu), 1);
/*