--- /dev/null
+/*
+ * Driver for the RTC in Marvell SoCs.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/gfp.h>
+#include <linux/module.h>
+
+
+#define RTC_TIME_REG_OFFS 0
+#define RTC_SECONDS_OFFS 0
+#define RTC_MINUTES_OFFS 8
+#define RTC_HOURS_OFFS 16
+#define RTC_WDAY_OFFS 24
+#define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */
+
+#define RTC_DATE_REG_OFFS 4
+#define RTC_MDAY_OFFS 0
+#define RTC_MONTH_OFFS 8
+#define RTC_YEAR_OFFS 16
+
+#define RTC_ALARM_TIME_REG_OFFS 8
+#define RTC_ALARM_DATE_REG_OFFS 0xc
+#define RTC_ALARM_VALID (1 << 7)
+
+#define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10
+#define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14
+
+struct rtc_plat_data {
+ struct rtc_device *rtc;
+ void __iomem *ioaddr;
+ int irq;
+ struct clk *clk;
+};
+
+static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 rtc_reg;
+
+ rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) |
+ (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) |
+ (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) |
+ (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS);
+ writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS);
+
+ rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) |
+ (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) |
+ (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS);
+ writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS);
+
+ return 0;
+}
+
+static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 rtc_time, rtc_date;
+ unsigned int year, month, day, hour, minute, second, wday;
+
+ rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS);
+ rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS);
+
+ second = rtc_time & 0x7f;
+ minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f;
+ hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */
+ wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7;
+
+ day = rtc_date & 0x3f;
+ month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f;
+ year = (rtc_date >> RTC_YEAR_OFFS) & 0xff;
+
+ tm->tm_sec = bcd2bin(second);
+ tm->tm_min = bcd2bin(minute);
+ tm->tm_hour = bcd2bin(hour);
+ tm->tm_mday = bcd2bin(day);
+ tm->tm_wday = bcd2bin(wday);
+ tm->tm_mon = bcd2bin(month) - 1;
+ /* hw counts from year 2000, but tm_year is relative to 1900 */
+ tm->tm_year = bcd2bin(year) + 100;
+
+ return rtc_valid_tm(tm);
+}
+
+static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 rtc_time, rtc_date;
+ unsigned int year, month, day, hour, minute, second, wday;
+
+ rtc_time = readl(ioaddr + RTC_ALARM_TIME_REG_OFFS);
+ rtc_date = readl(ioaddr + RTC_ALARM_DATE_REG_OFFS);
+
+ second = rtc_time & 0x7f;
+ minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f;
+ hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */
+ wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7;
+
+ day = rtc_date & 0x3f;
+ month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f;
+ year = (rtc_date >> RTC_YEAR_OFFS) & 0xff;
+
+ alm->time.tm_sec = bcd2bin(second);
+ alm->time.tm_min = bcd2bin(minute);
+ alm->time.tm_hour = bcd2bin(hour);
+ alm->time.tm_mday = bcd2bin(day);
+ alm->time.tm_wday = bcd2bin(wday);
+ alm->time.tm_mon = bcd2bin(month) - 1;
+ /* hw counts from year 2000, but tm_year is relative to 1900 */
+ alm->time.tm_year = bcd2bin(year) + 100;
+
+ if (rtc_valid_tm(&alm->time) < 0) {
+ dev_err(dev, "retrieved alarm date/time is not valid.\n");
+ rtc_time_to_tm(0, &alm->time);
+ }
+
+ alm->enabled = !!readl(ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+ return 0;
+}
+
+static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 rtc_reg = 0;
+
+ if (alm->time.tm_sec >= 0)
+ rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec))
+ << RTC_SECONDS_OFFS;
+ if (alm->time.tm_min >= 0)
+ rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min))
+ << RTC_MINUTES_OFFS;
+ if (alm->time.tm_hour >= 0)
+ rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour))
+ << RTC_HOURS_OFFS;
+
+ writel(rtc_reg, ioaddr + RTC_ALARM_TIME_REG_OFFS);
+
+ if (alm->time.tm_mday >= 0)
+ rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday))
+ << RTC_MDAY_OFFS;
+ else
+ rtc_reg = 0;
+
+ if (alm->time.tm_mon >= 0)
+ rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1))
+ << RTC_MONTH_OFFS;
+
+ if (alm->time.tm_year >= 0)
+ rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year % 100))
+ << RTC_YEAR_OFFS;
+
+ writel(rtc_reg, ioaddr + RTC_ALARM_DATE_REG_OFFS);
+ writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS);
+ writel(alm->enabled ? 1 : 0,
+ ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+
+ return 0;
+}
+
+static int mv_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+ void __iomem *ioaddr = pdata->ioaddr;
+
+ if (pdata->irq < 0)
+ return -EINVAL; /* fall back into rtc-dev's emulation */
+
+ if (enabled)
+ writel(1, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+ else
+ writel(0, ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+ return 0;
+}
+
+static irqreturn_t mv_rtc_interrupt(int irq, void *data)
+{
+ struct rtc_plat_data *pdata = data;
+ void __iomem *ioaddr = pdata->ioaddr;
+
+ /* alarm irq? */
+ if (!readl(ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS))
+ return IRQ_NONE;
+
+ /* clear interrupt */
+ writel(0, ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS);
+ rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF);
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops mv_rtc_ops = {
+ .read_time = mv_rtc_read_time,
+ .set_time = mv_rtc_set_time,
+};
+
+static const struct rtc_class_ops mv_rtc_alarm_ops = {
+ .read_time = mv_rtc_read_time,
+ .set_time = mv_rtc_set_time,
+ .read_alarm = mv_rtc_read_alarm,
+ .set_alarm = mv_rtc_set_alarm,
+ .alarm_irq_enable = mv_rtc_alarm_irq_enable,
+};
+
+static int __init mv_rtc_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct rtc_plat_data *pdata;
+ u32 rtc_time;
+ u32 rtc_date;
+ int ret = 0;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pdata->ioaddr))
+ return PTR_ERR(pdata->ioaddr);
+
+ pdata->clk = devm_clk_get(&pdev->dev, NULL);
+ /* Not all SoCs require a clock.*/
+ if (!IS_ERR(pdata->clk))
+ clk_prepare_enable(pdata->clk);
+
+ /* make sure the 24 hours mode is enabled */
+ rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS);
+ if (rtc_time & RTC_HOURS_12H_MODE) {
+ dev_err(&pdev->dev, "24 Hours mode not supported.\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* make sure it is actually functional */
+ if (rtc_time == 0x01000000) {
+ ssleep(1);
+ rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS);
+ if (rtc_time == 0x01000000) {
+ dev_err(&pdev->dev, "internal RTC not ticking\n");
+ ret = -ENODEV;
+ goto out;
+ }
+ }
+
+ /*
+ * A date after January 19th, 2038 does not fit on 32 bits and
+ * will confuse the kernel and userspace. Reset to a sane date
+ * (January 1st, 2013) if we're after 2038.
+ */
+ rtc_date = readl(pdata->ioaddr + RTC_DATE_REG_OFFS);
+ if (bcd2bin((rtc_date >> RTC_YEAR_OFFS) & 0xff) >= 38) {
+ dev_info(&pdev->dev, "invalid RTC date, resetting to January 1st, 2013\n");
+ writel(0x130101, pdata->ioaddr + RTC_DATE_REG_OFFS);
+ }
+
+ pdata->irq = platform_get_irq(pdev, 0);
+
+ platform_set_drvdata(pdev, pdata);
+
+ if (pdata->irq >= 0) {
+ device_init_wakeup(&pdev->dev, 1);
+ pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &mv_rtc_alarm_ops,
+ THIS_MODULE);
+ } else {
+ pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &mv_rtc_ops, THIS_MODULE);
+ }
+ if (IS_ERR(pdata->rtc)) {
+ ret = PTR_ERR(pdata->rtc);
+ goto out;
+ }
+
+ if (pdata->irq >= 0) {
+ writel(0, pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS);
+ if (devm_request_irq(&pdev->dev, pdata->irq, mv_rtc_interrupt,
+ IRQF_SHARED,
+ pdev->name, pdata) < 0) {
+ dev_warn(&pdev->dev, "interrupt not available.\n");
+ pdata->irq = -1;
+ }
+ }
+
+ return 0;
+out:
+ if (!IS_ERR(pdata->clk))
+ clk_disable_unprepare(pdata->clk);
+
+ return ret;
+}
+
+static int __exit mv_rtc_remove(struct platform_device *pdev)
+{
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+
+ if (pdata->irq >= 0)
+ device_init_wakeup(&pdev->dev, 0);
+
+ if (!IS_ERR(pdata->clk))
+ clk_disable_unprepare(pdata->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id rtc_mv_of_match_table[] = {
+ { .compatible = "marvell,orion-rtc", },
+ {}
+};
+#endif
+
+static struct platform_driver mv_rtc_driver = {
+ .remove = __exit_p(mv_rtc_remove),
+ .driver = {
+ .name = "rtc-mv",
+ .of_match_table = of_match_ptr(rtc_mv_of_match_table),
+ },
+};
+
+module_platform_driver_probe(mv_rtc_driver, mv_rtc_probe);
+
+MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>");
+MODULE_DESCRIPTION("Marvell RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:rtc-mv");
Code Review / kvmfornfv.git / blobdiff