ENGR00154648 [Mx6]SMP hotplug sometimes hang

1. boot_secondary ioremap need unmap, or the
stress test of hot-plug and suspend/resume will
cause the virtual address space leak;

2. Disable secondary CPUs need done by CPU0, move
the SRC_SCR setting to platform_cpu_kill.

Signed-off-by: Anson Huang <b20788@freescale.com>

diff --git a/arch/arm/mach-mx6/plat_hotplug.c b/arch/arm/mach-mx6/plat_hotplug.c
index 6ef057f6865ab36aaa303bf5313d46add848e38c..3a124b084744499b505fbde60da2a3e798763de9 100644 (file)
--- a/arch/arm/mach-mx6/plat_hotplug.c
+++ b/arch/arm/mach-mx6/plat_hotplug.c
@@ -26,9 +26,28 @@
 #include <linux/sched.h>
 #include <asm/cacheflush.h>
 
-
+static atomic_t cpu_die_done = ATOMIC_INIT(0);
 int platform_cpu_kill(unsigned int cpu)
 {
+       void __iomem *src_base = IO_ADDRESS(SRC_BASE_ADDR);
+       unsigned int val;
+
+       val = jiffies;
+       /* wait secondary cpu to die, timeout is 500ms */
+       while (atomic_read(&cpu_die_done) == 0) {
+               if (time_after(jiffies, (unsigned long)(val + HZ / 2))) {
+                       printk(KERN_WARNING "cpu %d: cpu could not die\n", cpu);
+                       break;
+               }
+       }
+       /*
+        * we're ready for shutdown now, so do it
+        */
+       val = readl(src_base + SRC_SCR_OFFSET);
+       val &= ~(1 << (BP_SRC_SCR_CORES_DBG_RST + cpu));
+       writel(val, src_base + SRC_SCR_OFFSET);
+
+       atomic_set(&cpu_die_done, 0);
        return 1;
 }
 
@@ -38,23 +57,16 @@ int platform_cpu_kill(unsigned int cpu)
  */
 void platform_cpu_die(unsigned int cpu)
 {
-       void __iomem *src_base = IO_ADDRESS(SRC_BASE_ADDR);
-       unsigned int val;
-
        if (cpu == 0) {
                printk(KERN_ERR "CPU0 can't be disabled!\n");
                return;
        }
+
        flush_cache_all();
        dsb();
 
-       /*
-        * we're ready for shutdown now, so do it
-        */
-       val = readl(src_base + SRC_SCR_OFFSET);
-       val &= ~(1 << (BP_SRC_SCR_CORES_DBG_RST + cpu));
-       writel(val, src_base + SRC_SCR_OFFSET);
-
+       /* tell cpu0 to kill me */
+       atomic_set(&cpu_die_done, 1);
        for (;;) {
                /*
                 * Execute WFI

diff --git a/arch/arm/mach-mx6/platsmp.c b/arch/arm/mach-mx6/platsmp.c
index 123063b31ecc23caa873011be6e2ce4cd3b3ba9c..5155efe0d6da304afe95b0295073f9a3e455371f 100644 (file)
--- a/arch/arm/mach-mx6/platsmp.c
+++ b/arch/arm/mach-mx6/platsmp.c
@@ -104,6 +104,8 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
        writel(0, src_base + SRC_GPR1_OFFSET + 4 * 2 * cpu + 4);
        smp_send_reschedule(cpu);
 
+       /* unmap iram base */
+       iounmap(boot_iram_base);
        /*
        * now the secondary core is starting up let it run its
        * calibrations, then wait for it to finish