1 files changed, 34 insertions, 22 deletions

diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
index 8fcec1cc101e..3e7a4b761a95 100644
--- a/arch/arm/mach-rockchip/platsmp.c
+++ b/arch/arm/mach-rockchip/platsmp.c
@@ -72,29 +72,22 @@ static struct reset_control *rockchip_get_core_reset(int cpu)
 static int pmu_set_power_domain(int pd, bool on)
 {
 	u32 val = (on) ? 0 : BIT(pd);
+	struct reset_control *rstc = rockchip_get_core_reset(pd);
 	int ret;
 
+	if (IS_ERR(rstc) && read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
+		pr_err("%s: could not get reset control for core %d\n",
+		       __func__, pd);
+		return PTR_ERR(rstc);
+	}
+
 	/*
 	 * We need to soft reset the cpu when we turn off the cpu power domain,
 	 * or else the active processors might be stalled when the individual
 	 * processor is powered down.
 	 */
-	if (read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
-		struct reset_control *rstc = rockchip_get_core_reset(pd);
-
-		if (IS_ERR(rstc)) {
-			pr_err("%s: could not get reset control for core %d\n",
-			       __func__, pd);
-			return PTR_ERR(rstc);
-		}
-
-		if (on)
-			reset_control_deassert(rstc);
-		else
-			reset_control_assert(rstc);
-
-		reset_control_put(rstc);
-	}
+	if (!IS_ERR(rstc) && !on)
+		reset_control_assert(rstc);
 
 	ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
 	if (ret < 0) {
@@ -107,11 +100,17 @@ static int pmu_set_power_domain(int pd, bool on)
 		ret = pmu_power_domain_is_on(pd);
 		if (ret < 0) {
 			pr_err("%s: could not read power domain state\n",
-				 __func__);
+			       __func__);
 			return ret;
 		}
 	}
 
+	if (!IS_ERR(rstc)) {
+		if (on)
+			reset_control_deassert(rstc);
+		reset_control_put(rstc);
+	}
+
 	return 0;
 }
 
@@ -130,7 +129,7 @@ static int rockchip_boot_secondary(unsigned int cpu, struct task_struct *idle)
 
 	if (cpu >= ncores) {
 		pr_err("%s: cpu %d outside maximum number of cpus %d\n",
-							__func__, cpu, ncores);
+		       __func__, cpu, ncores);
 		return -ENXIO;
 	}
 
@@ -140,14 +139,19 @@ static int rockchip_boot_secondary(unsigned int cpu, struct task_struct *idle)
 		return ret;
 
 	if (read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
-		/* We communicate with the bootrom to active the cpus other
+		/*
+		 * We communicate with the bootrom to active the cpus other
 		 * than cpu0, after a blob of initialize code, they will
 		 * stay at wfe state, once they are actived, they will check
 		 * the mailbox:
 		 * sram_base_addr + 4: 0xdeadbeaf
 		 * sram_base_addr + 8: start address for pc
-		 * */
-		udelay(10);
+		 * The cpu0 need to wait the other cpus other than cpu0 entering
+		 * the wfe state.The wait time is affected by many aspects.
+		 * (e.g: cpu frequency, bootrom frequency, sram frequency, ...)
+		 */
+		mdelay(1); /* ensure the cpus other than cpu0 to startup */
+
 		writel(virt_to_phys(secondary_startup), sram_base_addr + 8);
 		writel(0xDEADBEAF, sram_base_addr + 4);
 		dsb_sev();
@@ -317,6 +321,13 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus)
 #ifdef CONFIG_HOTPLUG_CPU
 static int rockchip_cpu_kill(unsigned int cpu)
 {
+	/*
+	 * We need a delay here to ensure that the dying CPU can finish
+	 * executing v7_coherency_exit() and reach the WFI/WFE state
+	 * prior to having the power domain disabled.
+	 */
+	mdelay(1);
+
 	pmu_set_power_domain(0 + cpu, false);
 	return 1;
 }
@@ -324,7 +335,7 @@ static int rockchip_cpu_kill(unsigned int cpu)
 static void rockchip_cpu_die(unsigned int cpu)
 {
 	v7_exit_coherency_flush(louis);
-	while(1)
+	while (1)
 		cpu_do_idle();
 }
 #endif
@@ -337,4 +348,5 @@ static struct smp_operations rockchip_smp_ops __initdata = {
 	.cpu_die		= rockchip_cpu_die,
 #endif
 };
+
 CPU_METHOD_OF_DECLARE(rk3066_smp, "rockchip,rk3066-smp", &rockchip_smp_ops);