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-rw-r--r--drivers/rtc/rtc-davinci.c512
1 files changed, 512 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-davinci.c b/drivers/rtc/rtc-davinci.c
new file mode 100644
index 000000000..73f87a17c
--- /dev/null
+++ b/drivers/rtc/rtc-davinci.c
@@ -0,0 +1,512 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * DaVinci Power Management and Real Time Clock Driver for TI platforms
+ *
+ * Copyright (C) 2009 Texas Instruments, Inc
+ *
+ * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+/*
+ * The DaVinci RTC is a simple RTC with the following
+ * Sec: 0 - 59 : BCD count
+ * Min: 0 - 59 : BCD count
+ * Hour: 0 - 23 : BCD count
+ * Day: 0 - 0x7FFF(32767) : Binary count ( Over 89 years )
+ */
+
+/* PRTC interface registers */
+#define DAVINCI_PRTCIF_PID 0x00
+#define PRTCIF_CTLR 0x04
+#define PRTCIF_LDATA 0x08
+#define PRTCIF_UDATA 0x0C
+#define PRTCIF_INTEN 0x10
+#define PRTCIF_INTFLG 0x14
+
+/* PRTCIF_CTLR bit fields */
+#define PRTCIF_CTLR_BUSY BIT(31)
+#define PRTCIF_CTLR_SIZE BIT(25)
+#define PRTCIF_CTLR_DIR BIT(24)
+#define PRTCIF_CTLR_BENU_MSB BIT(23)
+#define PRTCIF_CTLR_BENU_3RD_BYTE BIT(22)
+#define PRTCIF_CTLR_BENU_2ND_BYTE BIT(21)
+#define PRTCIF_CTLR_BENU_LSB BIT(20)
+#define PRTCIF_CTLR_BENU_MASK (0x00F00000)
+#define PRTCIF_CTLR_BENL_MSB BIT(19)
+#define PRTCIF_CTLR_BENL_3RD_BYTE BIT(18)
+#define PRTCIF_CTLR_BENL_2ND_BYTE BIT(17)
+#define PRTCIF_CTLR_BENL_LSB BIT(16)
+#define PRTCIF_CTLR_BENL_MASK (0x000F0000)
+
+/* PRTCIF_INTEN bit fields */
+#define PRTCIF_INTEN_RTCSS BIT(1)
+#define PRTCIF_INTEN_RTCIF BIT(0)
+#define PRTCIF_INTEN_MASK (PRTCIF_INTEN_RTCSS \
+ | PRTCIF_INTEN_RTCIF)
+
+/* PRTCIF_INTFLG bit fields */
+#define PRTCIF_INTFLG_RTCSS BIT(1)
+#define PRTCIF_INTFLG_RTCIF BIT(0)
+#define PRTCIF_INTFLG_MASK (PRTCIF_INTFLG_RTCSS \
+ | PRTCIF_INTFLG_RTCIF)
+
+/* PRTC subsystem registers */
+#define PRTCSS_RTC_INTC_EXTENA1 (0x0C)
+#define PRTCSS_RTC_CTRL (0x10)
+#define PRTCSS_RTC_WDT (0x11)
+#define PRTCSS_RTC_TMR0 (0x12)
+#define PRTCSS_RTC_TMR1 (0x13)
+#define PRTCSS_RTC_CCTRL (0x14)
+#define PRTCSS_RTC_SEC (0x15)
+#define PRTCSS_RTC_MIN (0x16)
+#define PRTCSS_RTC_HOUR (0x17)
+#define PRTCSS_RTC_DAY0 (0x18)
+#define PRTCSS_RTC_DAY1 (0x19)
+#define PRTCSS_RTC_AMIN (0x1A)
+#define PRTCSS_RTC_AHOUR (0x1B)
+#define PRTCSS_RTC_ADAY0 (0x1C)
+#define PRTCSS_RTC_ADAY1 (0x1D)
+#define PRTCSS_RTC_CLKC_CNT (0x20)
+
+/* PRTCSS_RTC_INTC_EXTENA1 */
+#define PRTCSS_RTC_INTC_EXTENA1_MASK (0x07)
+
+/* PRTCSS_RTC_CTRL bit fields */
+#define PRTCSS_RTC_CTRL_WDTBUS BIT(7)
+#define PRTCSS_RTC_CTRL_WEN BIT(6)
+#define PRTCSS_RTC_CTRL_WDRT BIT(5)
+#define PRTCSS_RTC_CTRL_WDTFLG BIT(4)
+#define PRTCSS_RTC_CTRL_TE BIT(3)
+#define PRTCSS_RTC_CTRL_TIEN BIT(2)
+#define PRTCSS_RTC_CTRL_TMRFLG BIT(1)
+#define PRTCSS_RTC_CTRL_TMMD BIT(0)
+
+/* PRTCSS_RTC_CCTRL bit fields */
+#define PRTCSS_RTC_CCTRL_CALBUSY BIT(7)
+#define PRTCSS_RTC_CCTRL_DAEN BIT(5)
+#define PRTCSS_RTC_CCTRL_HAEN BIT(4)
+#define PRTCSS_RTC_CCTRL_MAEN BIT(3)
+#define PRTCSS_RTC_CCTRL_ALMFLG BIT(2)
+#define PRTCSS_RTC_CCTRL_AIEN BIT(1)
+#define PRTCSS_RTC_CCTRL_CAEN BIT(0)
+
+static DEFINE_SPINLOCK(davinci_rtc_lock);
+
+struct davinci_rtc {
+ struct rtc_device *rtc;
+ void __iomem *base;
+ int irq;
+};
+
+static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
+ u32 val, u32 addr)
+{
+ writel(val, davinci_rtc->base + addr);
+}
+
+static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
+{
+ return readl(davinci_rtc->base + addr);
+}
+
+static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
+{
+ while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
+ cpu_relax();
+}
+
+static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
+ unsigned long val, u8 addr)
+{
+ rtcif_wait(davinci_rtc);
+
+ rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB | addr, PRTCIF_CTLR);
+ rtcif_write(davinci_rtc, val, PRTCIF_LDATA);
+
+ rtcif_wait(davinci_rtc);
+}
+
+static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
+{
+ rtcif_wait(davinci_rtc);
+
+ rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR | PRTCIF_CTLR_BENL_LSB | addr,
+ PRTCIF_CTLR);
+
+ rtcif_wait(davinci_rtc);
+
+ return rtcif_read(davinci_rtc, PRTCIF_LDATA);
+}
+
+static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
+{
+ while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
+ PRTCSS_RTC_CCTRL_CALBUSY)
+ cpu_relax();
+}
+
+static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
+{
+ struct davinci_rtc *davinci_rtc = class_dev;
+ unsigned long events = 0;
+ u32 irq_flg;
+ u8 alm_irq, tmr_irq;
+ u8 rtc_ctrl, rtc_cctrl;
+ int ret = IRQ_NONE;
+
+ irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
+ PRTCIF_INTFLG_RTCSS;
+
+ alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
+ PRTCSS_RTC_CCTRL_ALMFLG;
+
+ tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
+ PRTCSS_RTC_CTRL_TMRFLG;
+
+ if (irq_flg) {
+ if (alm_irq) {
+ events |= RTC_IRQF | RTC_AF;
+ rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
+ rtc_cctrl |= PRTCSS_RTC_CCTRL_ALMFLG;
+ rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
+ } else if (tmr_irq) {
+ events |= RTC_IRQF | RTC_PF;
+ rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
+ rtc_ctrl |= PRTCSS_RTC_CTRL_TMRFLG;
+ rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
+ }
+
+ rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
+ PRTCIF_INTFLG);
+ rtc_update_irq(davinci_rtc->rtc, 1, events);
+
+ ret = IRQ_HANDLED;
+ }
+
+ return ret;
+}
+
+static int
+davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+ struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
+ u8 rtc_ctrl;
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&davinci_rtc_lock, flags);
+
+ rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
+
+ switch (cmd) {
+ case RTC_WIE_ON:
+ rtc_ctrl |= PRTCSS_RTC_CTRL_WEN | PRTCSS_RTC_CTRL_WDTFLG;
+ break;
+ case RTC_WIE_OFF:
+ rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
+ break;
+ default:
+ ret = -ENOIOCTLCMD;
+ }
+
+ rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
+
+ spin_unlock_irqrestore(&davinci_rtc_lock, flags);
+
+ return ret;
+}
+
+static void convertfromdays(u16 days, struct rtc_time *tm)
+{
+ int tmp_days, year, mon;
+
+ for (year = 2000;; year++) {
+ tmp_days = rtc_year_days(1, 12, year);
+ if (days >= tmp_days)
+ days -= tmp_days;
+ else {
+ for (mon = 0;; mon++) {
+ tmp_days = rtc_month_days(mon, year);
+ if (days >= tmp_days) {
+ days -= tmp_days;
+ } else {
+ tm->tm_year = year - 1900;
+ tm->tm_mon = mon;
+ tm->tm_mday = days + 1;
+ break;
+ }
+ }
+ break;
+ }
+ }
+}
+
+static void convert2days(u16 *days, struct rtc_time *tm)
+{
+ int i;
+ *days = 0;
+
+ for (i = 2000; i < 1900 + tm->tm_year; i++)
+ *days += rtc_year_days(1, 12, i);
+
+ *days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);
+}
+
+static int davinci_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
+ u16 days = 0;
+ u8 day0, day1;
+ unsigned long flags;
+
+ spin_lock_irqsave(&davinci_rtc_lock, flags);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);
+
+ spin_unlock_irqrestore(&davinci_rtc_lock, flags);
+
+ days |= day1;
+ days <<= 8;
+ days |= day0;
+
+ convertfromdays(days, tm);
+
+ return 0;
+}
+
+static int davinci_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
+ u16 days;
+ u8 rtc_cctrl;
+ unsigned long flags;
+
+ convert2days(&days, tm);
+
+ spin_lock_irqsave(&davinci_rtc_lock, flags);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);
+
+ rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
+ rtc_cctrl |= PRTCSS_RTC_CCTRL_CAEN;
+ rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
+
+ spin_unlock_irqrestore(&davinci_rtc_lock, flags);
+
+ return 0;
+}
+
+static int davinci_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enabled)
+{
+ struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
+ unsigned long flags;
+ u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
+
+ spin_lock_irqsave(&davinci_rtc_lock, flags);
+
+ if (enabled)
+ rtc_cctrl |= PRTCSS_RTC_CCTRL_DAEN |
+ PRTCSS_RTC_CCTRL_HAEN |
+ PRTCSS_RTC_CCTRL_MAEN |
+ PRTCSS_RTC_CCTRL_ALMFLG |
+ PRTCSS_RTC_CCTRL_AIEN;
+ else
+ rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
+
+ spin_unlock_irqrestore(&davinci_rtc_lock, flags);
+
+ return 0;
+}
+
+static int davinci_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
+ u16 days = 0;
+ u8 day0, day1;
+ unsigned long flags;
+
+ alm->time.tm_sec = 0;
+
+ spin_lock_irqsave(&davinci_rtc_lock, flags);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);
+
+ spin_unlock_irqrestore(&davinci_rtc_lock, flags);
+ days |= day1;
+ days <<= 8;
+ days |= day0;
+
+ convertfromdays(days, &alm->time);
+
+ alm->pending = !!(rtcss_read(davinci_rtc,
+ PRTCSS_RTC_CCTRL) &
+ PRTCSS_RTC_CCTRL_AIEN);
+ alm->enabled = alm->pending && device_may_wakeup(dev);
+
+ return 0;
+}
+
+static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
+{
+ struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
+ unsigned long flags;
+ u16 days;
+
+ convert2days(&days, &alm->time);
+
+ spin_lock_irqsave(&davinci_rtc_lock, flags);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);
+
+ davinci_rtcss_calendar_wait(davinci_rtc);
+ rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);
+
+ spin_unlock_irqrestore(&davinci_rtc_lock, flags);
+
+ return 0;
+}
+
+static const struct rtc_class_ops davinci_rtc_ops = {
+ .ioctl = davinci_rtc_ioctl,
+ .read_time = davinci_rtc_read_time,
+ .set_time = davinci_rtc_set_time,
+ .alarm_irq_enable = davinci_rtc_alarm_irq_enable,
+ .read_alarm = davinci_rtc_read_alarm,
+ .set_alarm = davinci_rtc_set_alarm,
+};
+
+static int __init davinci_rtc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct davinci_rtc *davinci_rtc;
+ int ret = 0;
+
+ davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
+ if (!davinci_rtc)
+ return -ENOMEM;
+
+ davinci_rtc->irq = platform_get_irq(pdev, 0);
+ if (davinci_rtc->irq < 0)
+ return davinci_rtc->irq;
+
+ davinci_rtc->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(davinci_rtc->base))
+ return PTR_ERR(davinci_rtc->base);
+
+ platform_set_drvdata(pdev, davinci_rtc);
+
+ davinci_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(davinci_rtc->rtc))
+ return PTR_ERR(davinci_rtc->rtc);
+
+ davinci_rtc->rtc->ops = &davinci_rtc_ops;
+ davinci_rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ davinci_rtc->rtc->range_max = RTC_TIMESTAMP_BEGIN_2000 + (1 << 16) * 86400ULL - 1;
+
+ rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
+ rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
+ rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);
+
+ rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
+ rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);
+
+ ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
+ 0, "davinci_rtc", davinci_rtc);
+ if (ret < 0) {
+ dev_err(dev, "unable to register davinci RTC interrupt\n");
+ return ret;
+ }
+
+ /* Enable interrupts */
+ rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
+ rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
+ PRTCSS_RTC_INTC_EXTENA1);
+
+ rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
+
+ device_init_wakeup(&pdev->dev, 0);
+
+ return rtc_register_device(davinci_rtc->rtc);
+}
+
+static int __exit davinci_rtc_remove(struct platform_device *pdev)
+{
+ struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);
+
+ device_init_wakeup(&pdev->dev, 0);
+
+ rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
+
+ return 0;
+}
+
+static struct platform_driver davinci_rtc_driver = {
+ .remove = __exit_p(davinci_rtc_remove),
+ .driver = {
+ .name = "rtc_davinci",
+ },
+};
+
+module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);
+
+MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
+MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 19:02:59 +0000