[ARM] 5349/1: VFP: Add PM code to save and restore current VFP state

[linux-2.6-omap-h63xx.git] / arch / arm / vfp / vfpmodule.c

diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 67ca340a7c85c364d184d15f92c1a9205f84f472..9f476a1be2cace8280a4f7dfad0d3fcf8f92cfc0 100644 (file)
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -322,6 +322,61 @@ static void vfp_enable(void *unused)
        set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11));
 }
 
+#ifdef CONFIG_PM
+#include <linux/sysdev.h>
+
+static int vfp_pm_suspend(struct sys_device *dev, pm_message_t state)
+{
+       struct thread_info *ti = current_thread_info();
+       u32 fpexc = fmrx(FPEXC);
+
+       /* if vfp is on, then save state for resumption */
+       if (fpexc & FPEXC_EN) {
+               printk(KERN_DEBUG "%s: saving vfp state\n", __func__);
+               vfp_save_state(&ti->vfpstate, fpexc);
+
+               /* disable, just in case */
+               fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN);
+       }
+
+       /* clear any information we had about last context state */
+       memset(last_VFP_context, 0, sizeof(last_VFP_context));
+
+       return 0;
+}
+
+static int vfp_pm_resume(struct sys_device *dev)
+{
+       /* ensure we have access to the vfp */
+       vfp_enable(NULL);
+
+       /* and disable it to ensure the next usage restores the state */
+       fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN);
+
+       return 0;
+}
+
+static struct sysdev_class vfp_pm_sysclass = {
+       .name           = "vfp",
+       .suspend        = vfp_pm_suspend,
+       .resume         = vfp_pm_resume,
+};
+
+static struct sys_device vfp_pm_sysdev = {
+       .cls    = &vfp_pm_sysclass,
+};
+
+static void vfp_pm_init(void)
+{
+       sysdev_class_register(&vfp_pm_sysclass);
+       sysdev_register(&vfp_pm_sysdev);
+}
+
+
+#else
+static inline void vfp_pm_init(void) { }
+#endif /* CONFIG_PM */
+
 #include <linux/smp.h>
 
 /*
@@ -365,6 +420,7 @@ static int __init vfp_init(void)
                vfp_vector = vfp_support_entry;
 
                thread_register_notifier(&vfp_notifier_block);
+               vfp_pm_init();
 
                /*
                 * We detected VFP, and the support code is