openwrt/target/linux/coldfire/patches/026-Add-RTC-driver-support-...

628 lines
17 KiB
Diff

From 40563ab5aa698191dbd8a05fe6053aa790eee2a1 Mon Sep 17 00:00:00 2001
From: Alison Wang <b18965@freescale.com>
Date: Thu, 4 Aug 2011 09:59:46 +0800
Subject: [PATCH 26/52] Add RTC driver support for MCF5445x
On-chip RTC module support for MCF54451 and MCF54455.
Using internal 32K clock to drive the rtc module.
Signed-off-by: Alison Wang <b18965@freescale.com>
---
drivers/rtc/Kconfig | 9 +
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-mcf.c | 583 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 593 insertions(+), 0 deletions(-)
create mode 100644 drivers/rtc/rtc-mcf.c
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -919,6 +919,15 @@ config RTC_DRV_MV
This driver can also be built as a module. If so, the module
will be called rtc-mv.
+config RTC_MCF
+ tristate "Freescale Coldfire Real Time Clock"
+ depends on COLDFIRE
+ help
+ If you say yes here you will get support for the on-chip Coldfire
+ Real-Time Clock.
+
+ If you build it as a module it will be call mcf-rtc.
+
config RTC_DRV_PS3
tristate "PS3 RTC"
depends on PPC_PS3
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -102,3 +102,4 @@ obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41
obj-$(CONFIG_RTC_DRV_WM831X) += rtc-wm831x.o
obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o
obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
+obj-$(CONFIG_RTC_MCF) += rtc-mcf.o
--- /dev/null
+++ b/drivers/rtc/rtc-mcf.c
@@ -0,0 +1,583 @@
+/*
+ * Copyright (C) 2004-2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * Implementation based on rtc-mxc.c
+ * This file contains Real Time Clock interface for Linux.
+ *
+ * This 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.
+ */
+
+#include <linux/rtc.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/uaccess.h>
+#include <asm/mcfsim.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+#ifdef readl
+#undef readl
+#endif
+
+#ifdef writel
+#undef writel
+#endif
+
+#define readl(addr) in_be32(addr)
+#define writel(val, addr) out_be32((addr), (val))
+
+#define RTC_INPUT_CLK_32768HZ 0x8000
+#define RTC_INPUT_CLK_32000HZ 0x7D00
+#define RTC_INPUT_CLK_38400HZ 0x9600
+#define RTC_INPUT_CLK_48000HZ 0xBB80
+
+#define PIT_ALL_ON (MCF_RTC_ISR_2HZ | MCF_RTC_ISR_SAM0 | MCF_RTC_ISR_SAM1 | \
+ MCF_RTC_ISR_SAM2 | MCF_RTC_ISR_SAM3 | MCF_RTC_ISR_SAM4 | \
+ MCF_RTC_ISR_SAM5 | MCF_RTC_ISR_SAM6 | MCF_RTC_ISR_SAM7)
+
+#define MAX_PIE_NUM 9
+#define MAX_PIE_FREQ 512
+const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
+ {2, MCF_RTC_ISR_2HZ},
+ {4, MCF_RTC_ISR_SAM0},
+ {8, MCF_RTC_ISR_SAM1},
+ {16, MCF_RTC_ISR_SAM2},
+ {32, MCF_RTC_ISR_SAM3},
+ {64, MCF_RTC_ISR_SAM4},
+ {128, MCF_RTC_ISR_SAM5},
+ {256, MCF_RTC_ISR_SAM6},
+ {MAX_PIE_FREQ, MCF_RTC_ISR_SAM7},
+};
+
+/* Those are the bits from a classic RTC we want to mimic */
+#define RTC_IRQF 0x80 /* any of the following 3 is active */
+#define RTC_PF 0x40 /* Periodic interrupt */
+#define RTC_AF 0x20 /* Alarm interrupt */
+#define RTC_UF 0x10 /* Update interrupt for 1Hz RTC */
+
+#define MCF_RTC_TIME 0
+#define MCF_RTC_ALARM 1
+
+struct rtc_plat_data {
+ struct rtc_device *rtc;
+ int irq;
+ unsigned int irqen;
+ int alrm_sec;
+ int alrm_min;
+ int alrm_hour;
+ int alrm_mday;
+};
+
+/*!
+ * @defgroup RTC Real Time Clock (RTC) Driver
+ */
+/*!
+ * @file rtc-mcf.c
+ * @brief Real Time Clock interface
+ *
+ * This file contains Real Time Clock interface for Linux.
+ *
+ * @ingroup RTC
+ */
+
+#define RTC_VERSION "0.1"
+
+static u32 rtc_freq = 2; /* minimun value for PIE */
+static unsigned long rtc_status;
+
+static struct rtc_time g_rtc_alarm = {
+ .tm_year = 0,
+ .tm_mon = 0,
+ .tm_mday = 0,
+ .tm_hour = 0,
+ .tm_mon = 0,
+ .tm_sec = 0,
+};
+
+static DEFINE_SPINLOCK(rtc_lock);
+
+/*!
+ * This function is used to obtain the RTC time or the alarm value in
+ * second.
+ *
+ * @param time_alarm use MCF_RTC_TIME for RTC time value;
+ * MCF_RTC_ALARM for alarm value
+ *
+ * @return The RTC time or alarm time in second.
+ */
+static u32 get_alarm_or_time(struct device *dev, int time_alarm)
+{
+ u32 day, hr, min, sec, hr_min;
+
+ if (time_alarm == MCF_RTC_TIME) {
+ day = MCF_RTC_DAYS_DAYS(readl(MCF_RTC_DAYS));
+ hr_min = readl(MCF_RTC_HOURMIN);
+ sec = MCF_RTC_SECONDS_SECONDS(readl(MCF_RTC_SECONDS));
+ } else if (time_alarm == MCF_RTC_ALARM) {
+ day = MCF_RTC_ALRM_DAY_DAYS(readl(MCF_RTC_ALRM_DAY));
+ hr_min = readl(MCF_RTC_ALRM_HM);
+ sec = MCF_RTC_ALRM_SEC_SECONDS(readl(MCF_RTC_ALRM_SEC));
+ } else {
+ panic("wrong value for time_alarm=%d\n", time_alarm);
+ }
+
+ hr = (hr_min >> 8) & 0x001F;
+ min = hr_min & 0x003F;
+
+ return (((day * 24 + hr) * 60) + min) * 60 + sec;
+}
+
+/*!
+ * This function sets the RTC alarm value or the time value.
+ *
+ * @param time_alarm the new alarm value to be updated in the RTC
+ * @param time use MCF_RTC_TIME for RTC time value;
+ * MCF_RTC_ALARM for alarm value
+ */
+static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
+{
+ u32 day, hr, min, sec, temp;
+
+ day = time / 86400;
+ time -= day * 86400;
+ /* time is within a day now */
+ hr = time / 3600;
+ time -= hr * 3600;
+ /* time is within an hour now */
+ min = time / 60;
+ sec = time - min * 60;
+
+ temp = (hr << 8) + min;
+
+ if (time_alarm == MCF_RTC_TIME) {
+ writel(day, MCF_RTC_DAYS);
+ writel(sec, MCF_RTC_SECONDS);
+ writel(temp, MCF_RTC_HOURMIN);
+ } else if (time_alarm == MCF_RTC_ALARM) {
+ writel(day, MCF_RTC_ALRM_DAY);
+ writel(sec, MCF_RTC_ALRM_SEC);
+ writel(temp, MCF_RTC_ALRM_HM);
+ } else {
+ panic("wrong value for time_alarm=%d\n", time_alarm);
+ }
+}
+
+/*!
+ * This function updates the RTC alarm registers and then clears all the
+ * interrupt status bits.
+ *
+ * @param alrm the new alarm value to be updated in the RTC
+ *
+ * @return 0 if successful; non-zero otherwise.
+ */
+static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
+{
+ struct rtc_time alarm_tm, now_tm;
+ unsigned long now, time;
+ int ret;
+
+ now = get_alarm_or_time(dev, MCF_RTC_TIME);
+ rtc_time_to_tm(now, &now_tm);
+ alarm_tm.tm_year = now_tm.tm_year;
+ alarm_tm.tm_mon = now_tm.tm_mon;
+ alarm_tm.tm_mday = now_tm.tm_mday;
+ alarm_tm.tm_hour = alrm->tm_hour;
+ alarm_tm.tm_min = alrm->tm_min;
+ alarm_tm.tm_sec = alrm->tm_sec;
+ rtc_tm_to_time(&now_tm, &now);
+ rtc_tm_to_time(&alarm_tm, &time);
+ if (time < now) {
+ time += 60 * 60 * 24;
+ rtc_time_to_tm(time, &alarm_tm);
+ }
+ ret = rtc_tm_to_time(&alarm_tm, &time);
+
+ /* clear all the interrupt status bits */
+ writel(readl(MCF_RTC_ISR), MCF_RTC_ISR);
+
+ set_alarm_or_time(dev, MCF_RTC_ALARM, time);
+
+ return ret;
+}
+
+/*!
+ * This function is the RTC interrupt service routine.
+ *
+ * @param irq RTC IRQ number
+ * @param dev_id device ID which is not used
+ *
+ * @return IRQ_HANDLED as defined in the include/linux/interrupt.h file.
+ */
+static irqreturn_t mcf_rtc_interrupt(int irq, void *dev_id)
+{
+ struct platform_device *pdev = dev_id;
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+ u32 status, events = 0;
+
+ spin_lock(&rtc_lock);
+
+ /* clear interrupt sources */
+ status = readl(MCF_RTC_ISR) & readl(MCF_RTC_IER);
+ writel(status, MCF_RTC_ISR);
+
+ /* clear alarm interrupt if it has occurred */
+ if (status & MCF_RTC_ISR_ALM)
+ status &= ~MCF_RTC_ISR_ALM;
+
+ /* update irq data & counter */
+ if (status & MCF_RTC_ISR_ALM)
+ events |= (RTC_AF | RTC_IRQF);
+ if (status & MCF_RTC_ISR_1HZ)
+ events |= (RTC_UF | RTC_IRQF);
+ if (status & PIT_ALL_ON)
+ events |= (RTC_PF | RTC_IRQF);
+
+ if ((status & MCF_RTC_ISR_ALM) && rtc_valid_tm(&g_rtc_alarm))
+ rtc_update_alarm(&pdev->dev, &g_rtc_alarm);
+
+ spin_unlock(&rtc_lock);
+ rtc_update_irq(pdata->rtc, 1, events);
+ return IRQ_HANDLED;
+}
+
+/*!
+ * clear all interrupts and release the IRQ
+ */
+static void mcf_rtc_release(struct device *dev)
+{
+ spin_lock_irq(&rtc_lock);
+ writel(0, MCF_RTC_IER); /* Disable all rtc interrupts */
+ writel(0x0000FFBF, MCF_RTC_ISR); /* Clear all interrupt status */
+ spin_unlock_irq(&rtc_lock);
+ rtc_status = 0;
+}
+
+/*!
+ * This function is used to support some ioctl calls directly.
+ * Other ioctl calls are supported indirectly through the
+ * arm/common/rtctime.c file.
+ *
+ * @param cmd ioctl command as defined in include/linux/rtc.h
+ * @param arg value for the ioctl command
+ *
+ * @return 0 if successful or negative value otherwise.
+ */
+static int mcf_rtc_ioctl(struct device *dev, unsigned int cmd,
+ unsigned long arg)
+{
+ int i;
+
+ switch (cmd) {
+ case RTC_PIE_OFF:
+ writel((readl(MCF_RTC_IER) & ~PIT_ALL_ON), MCF_RTC_IER);
+ return 0;
+ case RTC_IRQP_SET:
+ if (arg < 2 || arg > MAX_PIE_FREQ || (arg % 2) != 0)
+ return -EINVAL; /* Also make sure a power of 2Hz */
+ if ((arg > 64) && (!capable(CAP_SYS_RESOURCE)))
+ return -EACCES;
+ rtc_freq = arg;
+ return 0;
+ case RTC_IRQP_READ:
+ return put_user(rtc_freq, (u32 *) arg);
+ case RTC_PIE_ON:
+ for (i = 0; i < MAX_PIE_NUM; i++) {
+ if (PIE_BIT_DEF[i][0] == rtc_freq)
+ break;
+ }
+ if (i == MAX_PIE_NUM)
+ return -EACCES;
+ spin_lock_irq(&rtc_lock);
+ writel((readl(MCF_RTC_IER) | PIE_BIT_DEF[i][1]), MCF_RTC_IER);
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+ case RTC_AIE_OFF:
+ spin_lock_irq(&rtc_lock);
+ writel((readl(MCF_RTC_IER) & ~MCF_RTC_ISR_ALM), MCF_RTC_IER);
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+
+ case RTC_AIE_ON:
+ spin_lock_irq(&rtc_lock);
+ writel((readl(MCF_RTC_IER) | MCF_RTC_ISR_ALM), MCF_RTC_IER);
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+
+ case RTC_UIE_OFF: /* UIE is for the 1Hz interrupt */
+ spin_lock_irq(&rtc_lock);
+ writel((readl(MCF_RTC_IER) & ~MCF_RTC_ISR_1HZ), MCF_RTC_IER);
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+
+ case RTC_UIE_ON:
+ spin_lock_irq(&rtc_lock);
+ writel((readl(MCF_RTC_IER) | MCF_RTC_ISR_1HZ), MCF_RTC_IER);
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+ }
+ return -ENOIOCTLCMD;
+}
+
+/*!
+ * This function reads the current RTC time into tm in Gregorian date.
+ *
+ * @param tm contains the RTC time value upon return
+ *
+ * @return 0 if successful; non-zero otherwise.
+ */
+static int mcf_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ u32 val;
+
+ /* Avoid roll-over from reading the different registers */
+ do {
+ val = get_alarm_or_time(dev, MCF_RTC_TIME);
+ } while (val != get_alarm_or_time(dev, MCF_RTC_TIME));
+
+ rtc_time_to_tm(val, tm);
+ return 0;
+}
+
+/*!
+ * This function sets the internal RTC time based on tm in Gregorian date.
+ *
+ * @param tm the time value to be set in the RTC
+ *
+ * @return 0 if successful; non-zero otherwise.
+ */
+static int mcf_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ unsigned long time;
+ int ret;
+
+ ret = rtc_tm_to_time(tm, &time);
+ if (ret != 0)
+ return ret;
+
+ /* Avoid roll-over from reading the different registers */
+ do {
+ set_alarm_or_time(dev, MCF_RTC_TIME, time);
+ } while (time != get_alarm_or_time(dev, MCF_RTC_TIME));
+
+ return ret;
+}
+
+/*!
+ * This function reads the current alarm value into the passed in \b alrm
+ * argument. It updates the \b alrm's pending field value based on the whether
+ * an alarm interrupt occurs or not.
+ *
+ * @param alrm contains the RTC alarm value upon return
+ *
+ * @return 0 if successful; non-zero otherwise.
+ */
+static int mcf_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ rtc_time_to_tm(get_alarm_or_time(dev, MCF_RTC_ALARM), &alrm->time);
+ alrm->pending = ((readl(MCF_RTC_ISR) & MCF_RTC_ISR_ALM) != 0) ? 1 : 0;
+
+ return 0;
+}
+
+/*!
+ * This function sets the RTC alarm based on passed in alrm.
+ *
+ * @param alrm the alarm value to be set in the RTC
+ *
+ * @return 0 if successful; non-zero otherwise.
+ */
+static int mcf_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ int ret;
+
+ spin_lock_irq(&rtc_lock);
+ if (rtc_valid_tm(&alrm->time)) {
+ if (alrm->time.tm_sec > 59 ||
+ alrm->time.tm_hour > 23 || alrm->time.tm_min > 59) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = rtc_update_alarm(dev, &alrm->time);
+ } else {
+ ret = rtc_valid_tm(&alrm->time);
+ if (ret)
+ goto out;
+ ret = rtc_update_alarm(dev, &alrm->time);
+ }
+
+ if (ret == 0) {
+ memcpy(&g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
+
+ if (alrm->enabled) {
+ writel((readl(MCF_RTC_IER) | MCF_RTC_ISR_ALM),
+ MCF_RTC_IER);
+ } else {
+ writel((readl(MCF_RTC_IER) & ~MCF_RTC_ISR_ALM),
+ MCF_RTC_IER);
+ }
+ }
+out:
+ spin_unlock_irq(&rtc_lock);
+
+ return ret;
+}
+
+/*!
+ * This function is used to provide the content for the /proc/driver/rtc
+ * file.
+ *
+ * @param buf the buffer to hold the information that the driver
+ * wants to write
+ *
+ * @return The number of bytes written into the rtc file.
+ */
+static int mcf_rtc_proc(struct device *dev, struct seq_file *sq)
+{
+ char *p = sq->buf;
+
+ p += sprintf(p, "alarm_IRQ\t: %s\n",
+ (((readl(MCF_RTC_IER)) & MCF_RTC_ISR_ALM) !=
+ 0) ? "yes" : "no");
+ p += sprintf(p, "update_IRQ\t: %s\n",
+ (((readl(MCF_RTC_IER)) & MCF_RTC_ISR_1HZ) !=
+ 0) ? "yes" : "no");
+ p += sprintf(p, "periodic_IRQ\t: %s\n",
+ (((readl(MCF_RTC_IER)) & PIT_ALL_ON) !=
+ 0) ? "yes" : "no");
+ p += sprintf(p, "periodic_freq\t: %d\n", rtc_freq);
+
+ return p - (sq->buf);
+}
+
+/*!
+ * The RTC driver structure
+ */
+static struct rtc_class_ops mcf_rtc_ops = {
+ .ioctl = mcf_rtc_ioctl,
+ .read_time = mcf_rtc_read_time,
+ .set_time = mcf_rtc_set_time,
+ .read_alarm = mcf_rtc_read_alarm,
+ .set_alarm = mcf_rtc_set_alarm,
+ .proc = mcf_rtc_proc,
+};
+
+static int __devinit mcf_rtc_probe(struct platform_device *pdev)
+{
+ struct timespec tv;
+ struct rtc_device *rtc;
+ struct rtc_plat_data *pdata = NULL;
+ u32 ret = 0;
+
+ pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+ /* External clock is hard wired to 32768Hz.
+ * Clock settings 32K, 38.4K and 48K are defined above. */
+#if defined(CONFIG_M5227x) | defined(CONFIG_M5445X)
+ writel(0, MCF_RTC_GOCU);
+ writel(RTC_INPUT_CLK_32768HZ, MCF_RTC_GOCL);
+#endif
+ /* Configure and enable the RTC */
+ pdata->irq = MCFINT_VECBASE + MCFINT_RTC;
+ if (request_irq(pdata->irq, mcf_rtc_interrupt, IRQF_DISABLED,
+ pdev->name, pdev) < 0) {
+ dev_warn(&pdev->dev, "interrupt not available.\n");
+ pdata->irq = -1;
+ }
+
+ if (test_and_set_bit(1, &rtc_status))
+ return -EBUSY;
+
+ rtc = rtc_device_register(pdev->name, &pdev->dev, &mcf_rtc_ops,
+ THIS_MODULE);
+ if (IS_ERR(rtc)) {
+ ret = PTR_ERR(rtc);
+ if (pdata->irq >= 0)
+ free_irq(pdata->irq, pdev);
+ kfree(pdata);
+ return ret;
+ }
+ pdata->rtc = rtc;
+ platform_set_drvdata(pdev, pdata);
+
+ tv.tv_nsec = 0;
+ tv.tv_sec = get_alarm_or_time(&pdev->dev, MCF_RTC_TIME);
+
+#ifdef CONFIG_M5301x
+ writel(RTC_INPUT_CLK_32768HZ, MCF_RTC_GOC);
+ writel(0x08, MCF_RTC_OCEN);
+#endif
+ writeb(4, MCFSIM_ICR_RTC);
+
+ writel(MCF_RTC_IER_1HZ, MCF_RTC_IER); /* Unmask the 1Hz timer */
+
+ writel(MCF_RTC_CR_EN, MCF_RTC_CR);
+ if ((readl(MCF_RTC_CR) & MCF_RTC_CR_EN) == 0) {
+ printk(KERN_ALERT "RTC Hardware couldn't be enabled!\n");
+ return -EPERM;
+ }
+
+ printk(KERN_INFO "Real Time Clock Driver v%s\n", RTC_VERSION);
+ return ret;
+}
+
+static int __devexit mcf_rtc_remove(struct platform_device *pdev)
+{
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+
+ rtc_device_unregister(pdata->rtc);
+ if (pdata->irq >= 0)
+ free_irq(pdata->irq, pdev);
+ kfree(pdata);
+ mcf_rtc_release(NULL);
+ return 0;
+}
+
+/*!
+ * Contains pointers to the power management callback functions.
+ */
+MODULE_ALIAS("mcf-rtc");
+static struct platform_driver mcf_rtc_driver = {
+ .driver = {
+ .name = "mcf-rtc",
+ .owner = THIS_MODULE,
+ },
+ .probe = mcf_rtc_probe,
+ .remove = __devexit_p(mcf_rtc_remove),
+};
+
+/*!
+ * This function creates the /proc/driver/rtc file and registers the device RTC
+ * in the /dev/misc directory. It also reads the RTC value from external source
+ * and setup the internal RTC properly.
+ *
+ * @return -1 if RTC is failed to initialize; 0 is successful.
+ */
+static int __init mcf_rtc_init(void)
+{
+ return platform_driver_register(&mcf_rtc_driver);
+}
+
+/*!
+ * This function removes the /proc/driver/rtc file and un-registers the
+ * device RTC from the /dev/misc directory.
+ */
+static void __exit mcf_rtc_exit(void)
+{
+ platform_driver_unregister(&mcf_rtc_driver);
+
+}
+
+module_init(mcf_rtc_init);
+module_exit(mcf_rtc_exit);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("Real Time Clock Driver (MCF)");
+MODULE_LICENSE("GPL");