diff options
Diffstat (limited to 'arch/arm/mach-imx/hotplug.c')
| -rw-r--r-- | arch/arm/mach-imx/hotplug.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/hotplug.c b/arch/arm/mach-imx/hotplug.c index 3daf1ed..bbbb96e 100644 --- a/arch/arm/mach-imx/hotplug.c +++ b/arch/arm/mach-imx/hotplug.c @@ -14,6 +14,9 @@ #include <linux/jiffies.h> #include <asm/cp15.h> #include <asm/proc-fns.h> +#include<asm/smp.h> +#include<asm/smp_plat.h> +#include<asm/cacheflush.h> #include "common.h" @@ -38,6 +41,22 @@ static inline void cpu_enter_lowpower(void) : "cc"); } +static inline void cpu_leave_lowpower(void) +{ + unsigned int v; + + asm volatile( + " mrc p15, 0, %0, c1, c0, 0\n" + " orr %0, %0, %1\n" + " mcr p15, 0, %0, c1, c0, 0\n" + " mrc p15, 0, %0, c1, c0, 1\n" + " orr %0, %0, %2\n" + " mcr p15, 0, %0, c1, c0, 1\n" + : "=&r" (v) + : "Ir" (CR_C), "Ir" (0x40) + : "cc"); +} + /* * platform-specific code to shutdown a CPU * @@ -66,3 +85,41 @@ int imx_cpu_kill(unsigned int cpu) imx_set_cpu_arg(cpu, 0); return 1; } + +/* + * For LS102x platforms, shutdowning a CPU is not supported by hardware. + * So we just put the offline CPU into lower-power state here. + */ +void __ref ls1021a_cpu_die(unsigned int cpu) +{ + v7_exit_coherency_flush(louis); + + /*we are ready to enter lower-power state*/ + wfi(); + /* + * bring this CPU back into the world of cache + * coherency, and then restore interrupts + */ + cpu_leave_lowpower(); + + /* + * Do not return to the idle loop - jump back to the secondary + * cpu initialisation. There's some initialisation which needs + * to be repeated to undo the effects of taking the CPU offline. + */ + __asm__("mov sp, %0\n" + " mov fp, #0\n" + " b secondary_startup" + : + : "r" (task_stack_page(current) + THREAD_SIZE - 8)); +} + +int ls1021a_cpu_kill(unsigned int cpu) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(50); + + while (!ls1_get_cpu_arg(cpu)) + if (time_after(jiffies, timeout)) + return 0; + return 1; +} |