#include <linux/arm-smccc.h>
#include <linux/bitops.h>
#include <linux/compiler.h>
+#include <linux/cpuhotplug.h>
+#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/hardirq.h>
#include <linux/kernel.h>
#include <linux/kvm_host.h>
#include <linux/list.h>
#include <linux/mutex.h>
+#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/percpu.h>
#include <linux/platform_device.h>
+#include <linux/pm.h>
#include <linux/ptrace.h>
#include <linux/preempt.h>
+#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
static unsigned long sdei_entry_point;
struct sdei_event {
+ /* These three are protected by the sdei_list_lock */
struct list_head list;
+ bool reregister;
+ bool reenable;
+
u32 event_num;
u8 type;
u8 priority;
sdei_mask_local_cpu();
}
+static int sdei_cpuhp_down(unsigned int ignored)
+{
+ return sdei_mask_local_cpu();
+}
+
int sdei_unmask_local_cpu(void)
{
int err;
sdei_unmask_local_cpu();
}
+static int sdei_cpuhp_up(unsigned int ignored)
+{
+ return sdei_unmask_local_cpu();
+}
+
static void _ipi_private_reset(void *ignored)
{
int err;
return -ENOENT;
}
+ spin_lock(&sdei_list_lock);
+ event->reenable = true;
+ spin_unlock(&sdei_list_lock);
+
if (event->type == SDEI_EVENT_TYPE_SHARED)
err = sdei_api_event_enable(event->event_num);
mutex_unlock(&sdei_events_lock);
return -ENOENT;
}
+ spin_lock(&sdei_list_lock);
+ event->reenable = false;
+ spin_unlock(&sdei_list_lock);
+
if (event->type == SDEI_EVENT_TYPE_SHARED)
err = sdei_api_event_disable(event->event_num);
mutex_unlock(&sdei_events_lock);
{
lockdep_assert_held(&sdei_events_lock);
+ spin_lock(&sdei_list_lock);
+ event->reregister = false;
+ event->reenable = false;
+ spin_unlock(&sdei_list_lock);
+
if (event->type == SDEI_EVENT_TYPE_SHARED)
return sdei_api_event_unregister(event->event_num);
}
EXPORT_SYMBOL(sdei_event_unregister);
+/*
+ * unregister events, but don't destroy them as they are re-registered by
+ * sdei_reregister_shared().
+ */
+static int sdei_unregister_shared(void)
+{
+ int err = 0;
+ struct sdei_event *event;
+
+ mutex_lock(&sdei_events_lock);
+ spin_lock(&sdei_list_lock);
+ list_for_each_entry(event, &sdei_list, list) {
+ if (event->type != SDEI_EVENT_TYPE_SHARED)
+ continue;
+
+ err = _sdei_event_unregister(event);
+ if (err)
+ break;
+ }
+ spin_unlock(&sdei_list_lock);
+ mutex_unlock(&sdei_events_lock);
+
+ return err;
+}
+
static int sdei_api_event_register(u32 event_num, unsigned long entry_point,
void *arg, u64 flags, u64 affinity)
{
}
EXPORT_SYMBOL(sdei_event_register);
+static int sdei_reregister_event(struct sdei_event *event)
+{
+ int err;
+
+ lockdep_assert_held(&sdei_events_lock);
+
+ err = _sdei_event_register(event);
+ if (err) {
+ pr_err("Failed to re-register event %u\n", event->event_num);
+ sdei_event_destroy(event);
+ return err;
+ }
+
+ if (event->reenable) {
+ if (event->type == SDEI_EVENT_TYPE_SHARED)
+ err = sdei_api_event_enable(event->event_num);
+ }
+
+ if (err)
+ pr_err("Failed to re-enable event %u\n", event->event_num);
+
+ return err;
+}
+
+static int sdei_reregister_shared(void)
+{
+ int err = 0;
+ struct sdei_event *event;
+
+ mutex_lock(&sdei_events_lock);
+ spin_lock(&sdei_list_lock);
+ list_for_each_entry(event, &sdei_list, list) {
+ if (event->type != SDEI_EVENT_TYPE_SHARED)
+ continue;
+
+ if (event->reregister) {
+ err = sdei_reregister_event(event);
+ if (err)
+ break;
+ }
+ }
+ spin_unlock(&sdei_list_lock);
+ mutex_unlock(&sdei_events_lock);
+
+ return err;
+}
+
+/* When entering idle, mask/unmask events for this cpu */
+static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ int rv;
+
+ switch (action) {
+ case CPU_PM_ENTER:
+ rv = sdei_mask_local_cpu();
+ break;
+ case CPU_PM_EXIT:
+ case CPU_PM_ENTER_FAILED:
+ rv = sdei_unmask_local_cpu();
+ break;
+ default:
+ return NOTIFY_DONE;
+ }
+
+ if (rv)
+ return notifier_from_errno(rv);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block sdei_pm_nb = {
+ .notifier_call = sdei_pm_notifier,
+};
+
+static int sdei_device_suspend(struct device *dev)
+{
+ on_each_cpu(_ipi_mask_cpu, NULL, true);
+
+ return 0;
+}
+
+static int sdei_device_resume(struct device *dev)
+{
+ on_each_cpu(_ipi_unmask_cpu, NULL, true);
+
+ return 0;
+}
+
+/*
+ * We need all events to be reregistered when we resume from hibernate.
+ *
+ * The sequence is freeze->thaw. Reboot. freeze->restore. We unregister
+ * events during freeze, then re-register and re-enable them during thaw
+ * and restore.
+ */
+static int sdei_device_freeze(struct device *dev)
+{
+ int err;
+
+ cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
+
+ err = sdei_unregister_shared();
+ if (err)
+ return err;
+
+ return 0;
+}
+
+static int sdei_device_thaw(struct device *dev)
+{
+ int err;
+
+ /* re-register shared events */
+ err = sdei_reregister_shared();
+ if (err) {
+ pr_warn("Failed to re-register shared events...\n");
+ sdei_mark_interface_broken();
+ return err;
+ }
+
+ err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
+ &sdei_cpuhp_up, &sdei_cpuhp_down);
+ if (err)
+ pr_warn("Failed to re-register CPU hotplug notifier...\n");
+
+ return err;
+}
+
+static int sdei_device_restore(struct device *dev)
+{
+ int err;
+
+ err = sdei_platform_reset();
+ if (err)
+ return err;
+
+ return sdei_device_thaw(dev);
+}
+
+static const struct dev_pm_ops sdei_pm_ops = {
+ .suspend = sdei_device_suspend,
+ .resume = sdei_device_resume,
+ .freeze = sdei_device_freeze,
+ .thaw = sdei_device_thaw,
+ .restore = sdei_device_restore,
+};
+
+/*
+ * Mask all CPUs and unregister all events on panic, reboot or kexec.
+ */
+static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ /*
+ * We are going to reset the interface, after this there is no point
+ * doing work when we take CPUs offline.
+ */
+ cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
+
+ sdei_platform_reset();
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block sdei_reboot_nb = {
+ .notifier_call = sdei_reboot_notifier,
+};
+
static void sdei_smccc_smc(unsigned long function_id,
unsigned long arg0, unsigned long arg1,
unsigned long arg2, unsigned long arg3,
return 0;
}
- on_each_cpu(&_ipi_unmask_cpu, NULL, false);
+ err = cpu_pm_register_notifier(&sdei_pm_nb);
+ if (err) {
+ pr_warn("Failed to register CPU PM notifier...\n");
+ goto error;
+ }
+
+ err = register_reboot_notifier(&sdei_reboot_nb);
+ if (err) {
+ pr_warn("Failed to register reboot notifier...\n");
+ goto remove_cpupm;
+ }
+
+ err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
+ &sdei_cpuhp_up, &sdei_cpuhp_down);
+ if (err) {
+ pr_warn("Failed to register CPU hotplug notifier...\n");
+ goto remove_reboot;
+ }
return 0;
+
+remove_reboot:
+ unregister_reboot_notifier(&sdei_reboot_nb);
+
+remove_cpupm:
+ cpu_pm_unregister_notifier(&sdei_pm_nb);
+
+error:
+ sdei_mark_interface_broken();
+ return err;
}
static const struct of_device_id sdei_of_match[] = {
static struct platform_driver sdei_driver = {
.driver = {
.name = "sdei",
+ .pm = &sdei_pm_ops,
.of_match_table = sdei_of_match,
},
.probe = sdei_probe,
projects / linux-2.6-microblaze.git / commitdiff