diff options
Diffstat (limited to 'arch/arm/vfp/vfpmodule.c')
| -rw-r--r-- | arch/arm/vfp/vfpmodule.c | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 8063a322c790..bbf3da012afd 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -10,9 +10,12 @@ */ #include <linux/module.h> #include <linux/types.h> +#include <linux/cpu.h> #include <linux/kernel.h> +#include <linux/notifier.h> #include <linux/signal.h> #include <linux/sched.h> +#include <linux/smp.h> #include <linux/init.h> #include <asm/cputype.h> @@ -150,7 +153,7 @@ static struct notifier_block vfp_notifier_block = { * Raise a SIGFPE for the current process. * sicode describes the signal being raised. */ -void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs) +static void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs) { siginfo_t info; @@ -484,7 +487,27 @@ void vfp_flush_hwstate(struct thread_info *thread) put_cpu(); } -#include <linux/smp.h> +/* + * VFP hardware can lose all context when a CPU goes offline. + * As we will be running in SMP mode with CPU hotplug, we will save the + * hardware state at every thread switch. We clear our held state when + * a CPU has been killed, indicating that the VFP hardware doesn't contain + * a threads VFP state. When a CPU starts up, we re-enable access to the + * VFP hardware. + * + * Both CPU_DYING and CPU_STARTING are called on the CPU which + * is being offlined/onlined. + */ +static int vfp_hotplug(struct notifier_block *b, unsigned long action, + void *hcpu) +{ + if (action == CPU_DYING || action == CPU_DYING_FROZEN) { + unsigned int cpu = (long)hcpu; + last_VFP_context[cpu] = NULL; + } else if (action == CPU_STARTING || action == CPU_STARTING_FROZEN) + vfp_enable(NULL); + return NOTIFY_OK; +} /* * VFP support code initialisation. @@ -514,6 +537,8 @@ static int __init vfp_init(void) else if (vfpsid & FPSID_NODOUBLE) { printk("no double precision support\n"); } else { + hotcpu_notifier(vfp_hotplug, 0); + smp_call_function(vfp_enable, NULL, 1); VFP_arch = (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT; /* Extract the architecture version */ |
