From 40563ab5aa698191dbd8a05fe6053aa790eee2a1 Mon Sep 17 00:00:00 2001 From: Alison Wang 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 --- 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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");