diff options
Diffstat (limited to 'arch/arm/mach-integrator/time.c')
| -rw-r--r-- | arch/arm/mach-integrator/time.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/arm/mach-integrator/time.c b/arch/arm/mach-integrator/time.c new file mode 100644 index 00000000000..20729de2af2 --- /dev/null +++ b/arch/arm/mach-integrator/time.c @@ -0,0 +1,213 @@ +/* + * linux/arch/arm/mach-integrator/time.c + * + * Copyright (C) 2000-2001 Deep Blue Solutions Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/time.h> +#include <linux/mc146818rtc.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/device.h> + +#include <asm/hardware/amba.h> +#include <asm/hardware.h> +#include <asm/io.h> +#include <asm/uaccess.h> +#include <asm/rtc.h> + +#include <asm/mach/time.h> + +#define RTC_DR (0) +#define RTC_MR (4) +#define RTC_STAT (8) +#define RTC_EOI (8) +#define RTC_LR (12) +#define RTC_CR (16) +#define RTC_CR_MIE (1 << 0) + +extern int (*set_rtc)(void); +static void __iomem *rtc_base; + +static int integrator_set_rtc(void) +{ + __raw_writel(xtime.tv_sec, rtc_base + RTC_LR); + return 1; +} + +static void rtc_read_alarm(struct rtc_wkalrm *alrm) +{ + rtc_time_to_tm(readl(rtc_base + RTC_MR), &alrm->time); +} + +static int rtc_set_alarm(struct rtc_wkalrm *alrm) +{ + unsigned long time; + int ret; + + ret = rtc_tm_to_time(&alrm->time, &time); + if (ret == 0) + writel(time, rtc_base + RTC_MR); + return ret; +} + +static void rtc_read_time(struct rtc_time *tm) +{ + rtc_time_to_tm(readl(rtc_base + RTC_DR), tm); +} + +/* + * Set the RTC time. Unfortunately, we can't accurately set + * the point at which the counter updates. + * + * Also, since RTC_LR is transferred to RTC_CR on next rising + * edge of the 1Hz clock, we must write the time one second + * in advance. + */ +static int rtc_set_time(struct rtc_time *tm) +{ + unsigned long time; + int ret; + + ret = rtc_tm_to_time(tm, &time); + if (ret == 0) + writel(time + 1, rtc_base + RTC_LR); + + return ret; +} + +static struct rtc_ops rtc_ops = { + .owner = THIS_MODULE, + .read_time = rtc_read_time, + .set_time = rtc_set_time, + .read_alarm = rtc_read_alarm, + .set_alarm = rtc_set_alarm, +}; + +static irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + writel(0, rtc_base + RTC_EOI); + return IRQ_HANDLED; +} + +static int rtc_probe(struct amba_device *dev, void *id) +{ + int ret; + + if (rtc_base) + return -EBUSY; + + ret = amba_request_regions(dev, NULL); + if (ret) + goto out; + + rtc_base = ioremap(dev->res.start, SZ_4K); + if (!rtc_base) { + ret = -ENOMEM; + goto res_out; + } + + __raw_writel(0, rtc_base + RTC_CR); + __raw_writel(0, rtc_base + RTC_EOI); + + xtime.tv_sec = __raw_readl(rtc_base + RTC_DR); + + ret = request_irq(dev->irq[0], rtc_interrupt, SA_INTERRUPT, + "rtc-pl030", dev); + if (ret) + goto map_out; + + ret = register_rtc(&rtc_ops); + if (ret) + goto irq_out; + + set_rtc = integrator_set_rtc; + return 0; + + irq_out: + free_irq(dev->irq[0], dev); + map_out: + iounmap(rtc_base); + rtc_base = NULL; + res_out: + amba_release_regions(dev); + out: + return ret; +} + +static int rtc_remove(struct amba_device *dev) +{ + set_rtc = NULL; + + writel(0, rtc_base + RTC_CR); + + free_irq(dev->irq[0], dev); + unregister_rtc(&rtc_ops); + + iounmap(rtc_base); + rtc_base = NULL; + amba_release_regions(dev); + + return 0; +} + +static struct timespec rtc_delta; + +static int rtc_suspend(struct amba_device *dev, pm_message_t state) +{ + struct timespec rtc; + + rtc.tv_sec = readl(rtc_base + RTC_DR); + rtc.tv_nsec = 0; + save_time_delta(&rtc_delta, &rtc); + + return 0; +} + +static int rtc_resume(struct amba_device *dev) +{ + struct timespec rtc; + + rtc.tv_sec = readl(rtc_base + RTC_DR); + rtc.tv_nsec = 0; + restore_time_delta(&rtc_delta, &rtc); + + return 0; +} + +static struct amba_id rtc_ids[] = { + { + .id = 0x00041030, + .mask = 0x000fffff, + }, + { 0, 0 }, +}; + +static struct amba_driver rtc_driver = { + .drv = { + .name = "rtc-pl030", + }, + .probe = rtc_probe, + .remove = rtc_remove, + .suspend = rtc_suspend, + .resume = rtc_resume, + .id_table = rtc_ids, +}; + +static int __init integrator_rtc_init(void) +{ + return amba_driver_register(&rtc_driver); +} + +static void __exit integrator_rtc_exit(void) +{ + amba_driver_unregister(&rtc_driver); +} + +module_init(integrator_rtc_init); +module_exit(integrator_rtc_exit); |