--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Intel Corporation
+ * Author: Johannes Berg <johannes@sipsolutions.net>
+ */
+#include <linux/platform_device.h>
+#include <linux/time-internal.h>
+#include <linux/suspend.h>
+#include <linux/err.h>
+#include <linux/rtc.h>
+#include <kern_util.h>
+#include <irq_kern.h>
+#include <os.h>
+#include "rtc.h"
+
+static time64_t uml_rtc_alarm_time;
+static bool uml_rtc_alarm_enabled;
+static struct rtc_device *uml_rtc;
+static int uml_rtc_irq_fd, uml_rtc_irq;
+
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+
+static void uml_rtc_time_travel_alarm(struct time_travel_event *ev)
+{
+ uml_rtc_send_timetravel_alarm();
+}
+
+static struct time_travel_event uml_rtc_alarm_event = {
+ .fn = uml_rtc_time_travel_alarm,
+};
+#endif
+
+static int uml_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct timespec64 ts;
+
+ /* Use this to get correct time in time-travel mode */
+ read_persistent_clock64(&ts);
+ rtc_time64_to_tm(timespec64_to_ktime(ts) / NSEC_PER_SEC, tm);
+
+ return 0;
+}
+
+static int uml_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ rtc_time64_to_tm(uml_rtc_alarm_time, &alrm->time);
+ alrm->enabled = uml_rtc_alarm_enabled;
+
+ return 0;
+}
+
+static int uml_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
+{
+ unsigned long long secs;
+
+ if (!enable && !uml_rtc_alarm_enabled)
+ return 0;
+
+ uml_rtc_alarm_enabled = enable;
+
+ secs = uml_rtc_alarm_time - ktime_get_real_seconds();
+
+ if (time_travel_mode == TT_MODE_OFF) {
+ if (!enable) {
+ uml_rtc_disable_alarm();
+ return 0;
+ }
+
+ /* enable or update */
+ return uml_rtc_enable_alarm(secs);
+ } else {
+ time_travel_del_event(¨_rtc_alarm_event);
+
+ if (enable)
+ time_travel_add_event_rel(¨_rtc_alarm_event,
+ secs * NSEC_PER_SEC);
+ }
+
+ return 0;
+}
+
+static int uml_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ uml_rtc_alarm_irq_enable(dev, 0);
+ uml_rtc_alarm_time = rtc_tm_to_time64(&alrm->time);
+ uml_rtc_alarm_irq_enable(dev, alrm->enabled);
+
+ return 0;
+}
+
+static const struct rtc_class_ops uml_rtc_ops = {
+ .read_time = uml_rtc_read_time,
+ .read_alarm = uml_rtc_read_alarm,
+ .alarm_irq_enable = uml_rtc_alarm_irq_enable,
+ .set_alarm = uml_rtc_set_alarm,
+};
+
+static irqreturn_t uml_rtc_interrupt(int irq, void *data)
+{
+ unsigned long long c = 0;
+
+ /* alarm triggered, it's now off */
+ uml_rtc_alarm_enabled = false;
+
+ os_read_file(uml_rtc_irq_fd, &c, sizeof(c));
+ WARN_ON(c == 0);
+
+ pm_system_wakeup();
+ rtc_update_irq(uml_rtc, 1, RTC_IRQF | RTC_AF);
+
+ return IRQ_HANDLED;
+}
+
+static int uml_rtc_setup(void)
+{
+ int err;
+
+ err = uml_rtc_start(time_travel_mode != TT_MODE_OFF);
+ if (WARN(err < 0, "err = %d\n", err))
+ return err;
+
+ uml_rtc_irq_fd = err;
+
+ err = um_request_irq(UM_IRQ_ALLOC, uml_rtc_irq_fd, IRQ_READ,
+ uml_rtc_interrupt, 0, "rtc", NULL);
+ if (err < 0) {
+ uml_rtc_stop(time_travel_mode != TT_MODE_OFF);
+ return err;
+ }
+
+ irq_set_irq_wake(err, 1);
+
+ uml_rtc_irq = err;
+ return 0;
+}
+
+static void uml_rtc_cleanup(void)
+{
+ um_free_irq(uml_rtc_irq, NULL);
+ uml_rtc_stop(time_travel_mode != TT_MODE_OFF);
+}
+
+static int uml_rtc_probe(struct platform_device *pdev)
+{
+ int err;
+
+ err = uml_rtc_setup();
+ if (err)
+ return err;
+
+ uml_rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(uml_rtc)) {
+ err = PTR_ERR(uml_rtc);
+ goto cleanup;
+ }
+
+ uml_rtc->ops = ¨_rtc_ops;
+
+ device_init_wakeup(&pdev->dev, 1);
+
+ err = devm_rtc_register_device(uml_rtc);
+ if (err)
+ goto cleanup;
+
+ return 0;
+cleanup:
+ uml_rtc_cleanup();
+ return err;
+}
+
+static int uml_rtc_remove(struct platform_device *pdev)
+{
+ device_init_wakeup(&pdev->dev, 0);
+ uml_rtc_cleanup();
+ return 0;
+}
+
+static struct platform_driver uml_rtc_driver = {
+ .probe = uml_rtc_probe,
+ .remove = uml_rtc_remove,
+ .driver = {
+ .name = "uml-rtc",
+ },
+};
+
+static int __init uml_rtc_init(void)
+{
+ struct platform_device *pdev;
+ int err;
+
+ err = platform_driver_register(¨_rtc_driver);
+ if (err)
+ return err;
+
+ pdev = platform_device_alloc("uml-rtc", 0);
+ if (!pdev) {
+ err = -ENOMEM;
+ goto unregister;
+ }
+
+ err = platform_device_add(pdev);
+ if (err)
+ goto unregister;
+ return 0;
+
+unregister:
+ platform_device_put(pdev);
+ platform_driver_unregister(¨_rtc_driver);
+ return err;
+}
+device_initcall(uml_rtc_init);
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Intel Corporation
+ * Author: Johannes Berg <johannes@sipsolutions.net>
+ */
+#include <os.h>
+#include <errno.h>
+#include <sched.h>
+#include <unistd.h>
+#include <kern_util.h>
+#include <sys/select.h>
+#include <stdio.h>
+#include <sys/timerfd.h>
+#include "rtc.h"
+
+static int uml_rtc_irq_fds[2];
+
+void uml_rtc_send_timetravel_alarm(void)
+{
+ unsigned long long c = 1;
+
+ CATCH_EINTR(write(uml_rtc_irq_fds[1], &c, sizeof(c)));
+}
+
+int uml_rtc_start(bool timetravel)
+{
+ int err;
+
+ if (timetravel) {
+ int err = os_pipe(uml_rtc_irq_fds, 1, 1);
+ if (err)
+ goto fail;
+ } else {
+ uml_rtc_irq_fds[0] = timerfd_create(CLOCK_REALTIME, TFD_CLOEXEC);
+ if (uml_rtc_irq_fds[0] < 0) {
+ err = -errno;
+ goto fail;
+ }
+
+ /* apparently timerfd won't send SIGIO, use workaround */
+ sigio_broken(uml_rtc_irq_fds[0]);
+ err = add_sigio_fd(uml_rtc_irq_fds[0]);
+ if (err < 0) {
+ close(uml_rtc_irq_fds[0]);
+ goto fail;
+ }
+ }
+
+ return uml_rtc_irq_fds[0];
+fail:
+ uml_rtc_stop(timetravel);
+ return err;
+}
+
+int uml_rtc_enable_alarm(unsigned long long delta_seconds)
+{
+ struct itimerspec it = {
+ .it_value = {
+ .tv_sec = delta_seconds,
+ },
+ };
+
+ if (timerfd_settime(uml_rtc_irq_fds[0], 0, &it, NULL))
+ return -errno;
+ return 0;
+}
+
+void uml_rtc_disable_alarm(void)
+{
+ uml_rtc_enable_alarm(0);
+}
+
+void uml_rtc_stop(bool timetravel)
+{
+ if (timetravel)
+ os_close_file(uml_rtc_irq_fds[1]);
+ else
+ ignore_sigio_fd(uml_rtc_irq_fds[0]);
+ os_close_file(uml_rtc_irq_fds[0]);
+}
projects / platform / kernel / linux-starfive.git / commitdiff