--- /dev/null
+/*
+ * IBM OPAL RTC driver
+ * Copyright (C) 2014 IBM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#define DRVNAME "rtc-opal"
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/rtc.h>
+#include <linux/delay.h>
+#include <linux/bcd.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <asm/opal.h>
+#include <asm/firmware.h>
+
+static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm)
+{
+ tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) +
+ bcd2bin((y_m_d >> 16) & 0xff)) - 1900;
+ tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1;
+ tm->tm_mday = bcd2bin(y_m_d & 0xff);
+ tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff);
+ tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff);
+ tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff);
+
+ GregorianDay(tm);
+}
+
+static void tm_to_opal(struct rtc_time *tm, u32 *y_m_d, u64 *h_m_s_ms)
+{
+ *y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24;
+ *y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16;
+ *y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8;
+ *y_m_d |= ((u32)bin2bcd(tm->tm_mday));
+
+ *h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56;
+ *h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48;
+ *h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40;
+}
+
+static int opal_get_rtc_time(struct device *dev, struct rtc_time *tm)
+{
+ long rc = OPAL_BUSY;
+ u32 y_m_d;
+ u64 h_m_s_ms;
+ __be32 __y_m_d;
+ __be64 __h_m_s_ms;
+
+ while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+ rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms);
+ if (rc == OPAL_BUSY_EVENT)
+ opal_poll_events(NULL);
+ else
+ msleep(10);
+ }
+
+ if (rc != OPAL_SUCCESS)
+ return -EIO;
+
+ y_m_d = be32_to_cpu(__y_m_d);
+ h_m_s_ms = be64_to_cpu(__h_m_s_ms);
+ opal_to_tm(y_m_d, h_m_s_ms, tm);
+
+ return 0;
+}
+
+static int opal_set_rtc_time(struct device *dev, struct rtc_time *tm)
+{
+ long rc = OPAL_BUSY;
+ u32 y_m_d = 0;
+ u64 h_m_s_ms = 0;
+
+ tm_to_opal(tm, &y_m_d, &h_m_s_ms);
+ while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+ rc = opal_rtc_write(y_m_d, h_m_s_ms);
+ if (rc == OPAL_BUSY_EVENT)
+ opal_poll_events(NULL);
+ else
+ msleep(10);
+ }
+
+ return rc == OPAL_SUCCESS ? 0 : -EIO;
+}
+
+/*
+ * TPO Timed Power-On
+ *
+ * TPO get/set OPAL calls care about the hour and min and to make it consistent
+ * with the rtc utility time conversion functions, we use the 'u64' to store
+ * its value and perform bit shift by 32 before use..
+ */
+static int opal_get_tpo_time(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ __be32 __y_m_d, __h_m;
+ struct opal_msg msg;
+ int rc, token;
+ u64 h_m_s_ms;
+ u32 y_m_d;
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ if (token != -ERESTARTSYS)
+ pr_err("Failed to get the async token\n");
+
+ return token;
+ }
+
+ rc = opal_tpo_read(token, &__y_m_d, &__h_m);
+ if (rc != OPAL_ASYNC_COMPLETION) {
+ rc = -EIO;
+ goto exit;
+ }
+
+ rc = opal_async_wait_response(token, &msg);
+ if (rc) {
+ rc = -EIO;
+ goto exit;
+ }
+
+ rc = be64_to_cpu(msg.params[1]);
+ if (rc != OPAL_SUCCESS) {
+ rc = -EIO;
+ goto exit;
+ }
+
+ y_m_d = be32_to_cpu(__y_m_d);
+ h_m_s_ms = ((u64)be32_to_cpu(__h_m) << 32);
+ opal_to_tm(y_m_d, h_m_s_ms, &alarm->time);
+
+exit:
+ opal_async_release_token(token);
+ return rc;
+}
+
+/* Set Timed Power-On */
+static int opal_set_tpo_time(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ u64 h_m_s_ms = 0, token;
+ struct opal_msg msg;
+ u32 y_m_d = 0;
+ int rc;
+
+ tm_to_opal(&alarm->time, &y_m_d, &h_m_s_ms);
+
+ token = opal_async_get_token_interruptible();
+ if (token < 0) {
+ if (token != -ERESTARTSYS)
+ pr_err("Failed to get the async token\n");
+
+ return token;
+ }
+
+ /* TPO, we care about hour and minute */
+ rc = opal_tpo_write(token, y_m_d,
+ (u32)((h_m_s_ms >> 32) & 0xffff0000));
+ if (rc != OPAL_ASYNC_COMPLETION) {
+ rc = -EIO;
+ goto exit;
+ }
+
+ rc = opal_async_wait_response(token, &msg);
+ if (rc) {
+ rc = -EIO;
+ goto exit;
+ }
+
+ rc = be64_to_cpu(msg.params[1]);
+ if (rc != OPAL_SUCCESS)
+ rc = -EIO;
+
+exit:
+ opal_async_release_token(token);
+ return rc;
+}
+
+static const struct rtc_class_ops opal_rtc_ops = {
+ .read_time = opal_get_rtc_time,
+ .set_time = opal_set_rtc_time,
+ .read_alarm = opal_get_tpo_time,
+ .set_alarm = opal_set_tpo_time,
+};
+
+static int opal_rtc_probe(struct platform_device *pdev)
+{
+ struct rtc_device *rtc;
+
+ if (pdev->dev.of_node && of_get_property(pdev->dev.of_node, "has-tpo",
+ NULL))
+ device_set_wakeup_capable(&pdev->dev, true);
+
+ rtc = devm_rtc_device_register(&pdev->dev, DRVNAME, &opal_rtc_ops,
+ THIS_MODULE);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ rtc->uie_unsupported = 1;
+
+ return 0;
+}
+
+static const struct of_device_id opal_rtc_match[] = {
+ {
+ .compatible = "ibm,opal-rtc",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, opal_rtc_match);
+
+static const struct platform_device_id opal_rtc_driver_ids[] = {
+ {
+ .name = "opal-rtc",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, opal_rtc_driver_ids);
+
+static struct platform_driver opal_rtc_driver = {
+ .probe = opal_rtc_probe,
+ .id_table = opal_rtc_driver_ids,
+ .driver = {
+ .name = DRVNAME,
+ .owner = THIS_MODULE,
+ .of_match_table = opal_rtc_match,
+ },
+};
+
+static int __init opal_rtc_init(void)
+{
+ if (!firmware_has_feature(FW_FEATURE_OPAL))
+ return -ENODEV;
+
+ return platform_driver_register(&opal_rtc_driver);
+}
+
+static void __exit opal_rtc_exit(void)
+{
+ platform_driver_unregister(&opal_rtc_driver);
+}
+
+MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
+MODULE_DESCRIPTION("IBM OPAL RTC driver");
+MODULE_LICENSE("GPL");
+
+module_init(opal_rtc_init);
+module_exit(opal_rtc_exit);
Code Review / kvmfornfv.git / blobdiff