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    Subject[PATCHv2 09/11] unicore32 core architecture: timer and time handling
    Date
    This patch implements timer and time.
    RTC and PWM device drivers are also here.

    Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
    ---
    arch/unicore32/include/asm/timex.h | 34 ++++
    arch/unicore32/kernel/pwm.c | 263 +++++++++++++++++++++++++
    arch/unicore32/kernel/rtc.c | 380 ++++++++++++++++++++++++++++++++++++
    arch/unicore32/kernel/time.c | 148 ++++++++++++++
    4 files changed, 825 insertions(+), 0 deletions(-)
    create mode 100644 arch/unicore32/include/asm/timex.h
    create mode 100644 arch/unicore32/kernel/pwm.c
    create mode 100644 arch/unicore32/kernel/rtc.c
    create mode 100644 arch/unicore32/kernel/time.c

    diff --git a/arch/unicore32/include/asm/timex.h b/arch/unicore32/include/asm/timex.h
    new file mode 100644
    index 0000000..faf16ba
    --- /dev/null
    +++ b/arch/unicore32/include/asm/timex.h
    @@ -0,0 +1,34 @@
    +/*
    + * linux/arch/unicore32/include/asm/timex.h
    + *
    + * Code specific to PKUnity SoC and UniCore ISA
    + *
    + * Copyright (C) 2001-2010 GUAN Xue-tao
    + *
    + * 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.
    + */
    +
    +#ifndef __UNICORE_TIMEX_H__
    +#define __UNICORE_TIMEX_H__
    +
    +#ifdef CONFIG_ARCH_FPGA
    +
    +/* in FPGA, APB clock is 33M, and OST clock is 32K, */
    +/* so, 1M is selected for timer interrupt correctly */
    +#define CLOCK_TICK_RATE (32*1024)
    +
    +#endif
    +
    +#if defined(CONFIG_PUV3_DB0913) \
    + || defined(CONFIG_PUV3_NB0916) \
    + || defined(CONFIG_PUV3_SMW0919)
    +
    +#define CLOCK_TICK_RATE (14318000)
    +
    +#endif
    +
    +#include <asm-generic/timex.h>
    +
    +#endif
    diff --git a/arch/unicore32/kernel/pwm.c b/arch/unicore32/kernel/pwm.c
    new file mode 100644
    index 0000000..4615d51
    --- /dev/null
    +++ b/arch/unicore32/kernel/pwm.c
    @@ -0,0 +1,263 @@
    +/*
    + * linux/arch/unicore32/kernel/pwm.c
    + *
    + * Code specific to PKUnity SoC and UniCore ISA
    + *
    + * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
    + * Copyright (C) 2001-2010 Guan Xuetao
    + *
    + * 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/platform_device.h>
    +#include <linux/slab.h>
    +#include <linux/err.h>
    +#include <linux/clk.h>
    +#include <linux/io.h>
    +#include <linux/pwm.h>
    +
    +#include <asm/div64.h>
    +#include <mach/hardware.h>
    +
    +struct pwm_device {
    + struct list_head node;
    + struct platform_device *pdev;
    +
    + const char *label;
    + struct clk *clk;
    + int clk_enabled;
    +
    + unsigned int use_count;
    + unsigned int pwm_id;
    +};
    +
    +/*
    + * period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE
    + * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
    + */
    +int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
    +{
    + unsigned long long c;
    + unsigned long period_cycles, prescale, pv, dc;
    +
    + if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
    + return -EINVAL;
    +
    + c = clk_get_rate(pwm->clk);
    + c = c * period_ns;
    + do_div(c, 1000000000);
    + period_cycles = c;
    +
    + if (period_cycles < 1)
    + period_cycles = 1;
    + prescale = (period_cycles - 1) / 1024;
    + pv = period_cycles / (prescale + 1) - 1;
    +
    + if (prescale > 63)
    + return -EINVAL;
    +
    + if (duty_ns == period_ns)
    + dc = OST_PWMDCCR_FDCYCLE;
    + else
    + dc = (pv + 1) * duty_ns / period_ns;
    +
    + /* NOTE: the clock to PWM has to be enabled first
    + * before writing to the registers
    + */
    + clk_enable(pwm->clk);
    + OST_PWMPWCR = prescale;
    + OST_PWMDCCR = pv - dc;
    + OST_PWMPCR = pv;
    + clk_disable(pwm->clk);
    +
    + return 0;
    +}
    +EXPORT_SYMBOL(pwm_config);
    +
    +int pwm_enable(struct pwm_device *pwm)
    +{
    + int rc = 0;
    +
    + if (!pwm->clk_enabled) {
    + rc = clk_enable(pwm->clk);
    + if (!rc)
    + pwm->clk_enabled = 1;
    + }
    + return rc;
    +}
    +EXPORT_SYMBOL(pwm_enable);
    +
    +void pwm_disable(struct pwm_device *pwm)
    +{
    + if (pwm->clk_enabled) {
    + clk_disable(pwm->clk);
    + pwm->clk_enabled = 0;
    + }
    +}
    +EXPORT_SYMBOL(pwm_disable);
    +
    +static DEFINE_MUTEX(pwm_lock);
    +static LIST_HEAD(pwm_list);
    +
    +struct pwm_device *pwm_request(int pwm_id, const char *label)
    +{
    + struct pwm_device *pwm;
    + int found = 0;
    +
    + mutex_lock(&pwm_lock);
    +
    + list_for_each_entry(pwm, &pwm_list, node) {
    + if (pwm->pwm_id == pwm_id) {
    + found = 1;
    + break;
    + }
    + }
    +
    + if (found) {
    + if (pwm->use_count == 0) {
    + pwm->use_count++;
    + pwm->label = label;
    + } else
    + pwm = ERR_PTR(-EBUSY);
    + } else
    + pwm = ERR_PTR(-ENOENT);
    +
    + mutex_unlock(&pwm_lock);
    + return pwm;
    +}
    +EXPORT_SYMBOL(pwm_request);
    +
    +void pwm_free(struct pwm_device *pwm)
    +{
    + mutex_lock(&pwm_lock);
    +
    + if (pwm->use_count) {
    + pwm->use_count--;
    + pwm->label = NULL;
    + } else
    + pr_warning("PWM device already freed\n");
    +
    + mutex_unlock(&pwm_lock);
    +}
    +EXPORT_SYMBOL(pwm_free);
    +
    +static inline void __add_pwm(struct pwm_device *pwm)
    +{
    + mutex_lock(&pwm_lock);
    + list_add_tail(&pwm->node, &pwm_list);
    + mutex_unlock(&pwm_lock);
    +}
    +
    +static struct pwm_device *pwm_probe(struct platform_device *pdev,
    + unsigned int pwm_id, struct pwm_device *parent_pwm)
    +{
    + struct pwm_device *pwm;
    + struct resource *r;
    + int ret = 0;
    +
    + pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
    + if (pwm == NULL) {
    + dev_err(&pdev->dev, "failed to allocate memory\n");
    + return ERR_PTR(-ENOMEM);
    + }
    +
    + pwm->clk = clk_get(NULL, "OST_CLK");
    + if (IS_ERR(pwm->clk)) {
    + ret = PTR_ERR(pwm->clk);
    + goto err_free;
    + }
    + pwm->clk_enabled = 0;
    +
    + pwm->use_count = 0;
    + pwm->pwm_id = pwm_id;
    + pwm->pdev = pdev;
    +
    + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    + if (r == NULL) {
    + dev_err(&pdev->dev, "no memory resource defined\n");
    + ret = -ENODEV;
    + goto err_free_clk;
    + }
    +
    + r = request_mem_region(r->start, resource_size(r), pdev->name);
    + if (r == NULL) {
    + dev_err(&pdev->dev, "failed to request memory resource\n");
    + ret = -EBUSY;
    + goto err_free_clk;
    + }
    +
    + __add_pwm(pwm);
    + platform_set_drvdata(pdev, pwm);
    + return pwm;
    +
    +err_free_clk:
    + clk_put(pwm->clk);
    +err_free:
    + kfree(pwm);
    + return ERR_PTR(ret);
    +}
    +
    +static int __devinit puv3_pwm_probe(struct platform_device *pdev)
    +{
    + struct pwm_device *pwm = pwm_probe(pdev, pdev->id, NULL);
    +
    + if (IS_ERR(pwm))
    + return PTR_ERR(pwm);
    +
    + return 0;
    +}
    +
    +static int __devexit pwm_remove(struct platform_device *pdev)
    +{
    + struct pwm_device *pwm;
    + struct resource *r;
    +
    + pwm = platform_get_drvdata(pdev);
    + if (pwm == NULL)
    + return -ENODEV;
    +
    + mutex_lock(&pwm_lock);
    + list_del(&pwm->node);
    + mutex_unlock(&pwm_lock);
    +
    + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    + release_mem_region(r->start, resource_size(r));
    +
    + clk_put(pwm->clk);
    + kfree(pwm);
    + return 0;
    +}
    +
    +static struct platform_driver puv3_pwm_driver = {
    + .driver = {
    + .name = "PKUnity-v3-PWM",
    + },
    + .probe = puv3_pwm_probe,
    + .remove = __devexit_p(pwm_remove),
    +};
    +
    +static int __init pwm_init(void)
    +{
    + int ret = 0;
    +
    + ret = platform_driver_register(&puv3_pwm_driver);
    + if (ret) {
    + printk(KERN_ERR "failed to register puv3_pwm_driver\n");
    + return ret;
    + }
    +
    + return ret;
    +}
    +arch_initcall(pwm_init);
    +
    +static void __exit pwm_exit(void)
    +{
    + platform_driver_unregister(&puv3_pwm_driver);
    +}
    +module_exit(pwm_exit);
    +
    +MODULE_LICENSE("GPL v2");
    diff --git a/arch/unicore32/kernel/rtc.c b/arch/unicore32/kernel/rtc.c
    new file mode 100644
    index 0000000..5e4db41
    --- /dev/null
    +++ b/arch/unicore32/kernel/rtc.c
    @@ -0,0 +1,380 @@
    +/*
    + * linux/arch/unicore32/kernel/rtc.c
    + *
    + * Code specific to PKUnity SoC and UniCore ISA
    + *
    + * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
    + * Copyright (C) 2001-2010 Guan Xuetao
    + *
    + * 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/fs.h>
    +#include <linux/string.h>
    +#include <linux/init.h>
    +#include <linux/platform_device.h>
    +#include <linux/interrupt.h>
    +#include <linux/rtc.h>
    +#include <linux/bcd.h>
    +#include <linux/clk.h>
    +#include <linux/log2.h>
    +#include <linux/slab.h>
    +#include <linux/uaccess.h>
    +#include <linux/io.h>
    +
    +#include <asm/irq.h>
    +#include <mach/hardware.h>
    +
    +static struct resource *puv3_rtc_mem;
    +
    +static int puv3_rtc_alarmno = IRQ_RTCAlarm;
    +static int puv3_rtc_tickno = IRQ_RTC;
    +
    +static DEFINE_SPINLOCK(puv3_rtc_pie_lock);
    +
    +/* IRQ Handlers */
    +
    +static irqreturn_t puv3_rtc_alarmirq(int irq, void *id)
    +{
    + struct rtc_device *rdev = id;
    +
    + RTC_RTSR |= RTC_RTSR_AL;
    + rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
    + return IRQ_HANDLED;
    +}
    +
    +static irqreturn_t puv3_rtc_tickirq(int irq, void *id)
    +{
    + struct rtc_device *rdev = id;
    +
    + RTC_RTSR |= RTC_RTSR_HZ;
    + rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
    + return IRQ_HANDLED;
    +}
    +
    +/* Update control registers */
    +static void puv3_rtc_setaie(int to)
    +{
    + unsigned int tmp;
    +
    + pr_debug("%s: aie=%d\n", __func__, to);
    +
    + tmp = RTC_RTSR & ~RTC_RTSR_ALE;
    +
    + if (to)
    + tmp |= RTC_RTSR_ALE;
    +
    + RTC_RTSR = tmp;
    +}
    +
    +static int puv3_rtc_setpie(struct device *dev, int enabled)
    +{
    + unsigned int tmp;
    +
    + pr_debug("%s: pie=%d\n", __func__, enabled);
    +
    + spin_lock_irq(&puv3_rtc_pie_lock);
    + tmp = RTC_RTSR & ~RTC_RTSR_HZE;
    +
    + if (enabled)
    + tmp |= RTC_RTSR_HZE;
    +
    + RTC_RTSR = tmp;
    + spin_unlock_irq(&puv3_rtc_pie_lock);
    +
    + return 0;
    +}
    +
    +static int puv3_rtc_setfreq(struct device *dev, int freq)
    +{
    + return 0;
    +}
    +
    +/* Time read/write */
    +
    +static int puv3_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
    +{
    + rtc_time_to_tm(RTC_RCNR, rtc_tm);
    +
    + pr_debug("read time %02x.%02x.%02x %02x/%02x/%02x\n",
    + rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
    + rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
    +
    + return 0;
    +}
    +
    +static int puv3_rtc_settime(struct device *dev, struct rtc_time *tm)
    +{
    + unsigned long rtc_count = 0;
    +
    + pr_debug("set time %02d.%02d.%02d %02d/%02d/%02d\n",
    + tm->tm_year, tm->tm_mon, tm->tm_mday,
    + tm->tm_hour, tm->tm_min, tm->tm_sec);
    +
    + rtc_tm_to_time(tm, &rtc_count);
    + RTC_RCNR = rtc_count;
    +
    + return 0;
    +}
    +
    +static int puv3_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
    +{
    + struct rtc_time *alm_tm = &alrm->time;
    +
    + rtc_time_to_tm(RTC_RTAR, alm_tm);
    +
    + alrm->enabled = RTC_RTSR & RTC_RTSR_ALE;
    +
    + pr_debug("read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
    + alrm->enabled,
    + alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
    + alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
    +
    + return 0;
    +}
    +
    +static int puv3_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
    +{
    + struct rtc_time *tm = &alrm->time;
    + unsigned long rtcalarm_count = 0;
    +
    + pr_debug("puv3_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
    + alrm->enabled,
    + tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
    + tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
    +
    + rtc_tm_to_time(tm, &rtcalarm_count);
    + RTC_RTAR = rtcalarm_count;
    +
    + puv3_rtc_setaie(alrm->enabled);
    +
    + if (alrm->enabled)
    + enable_irq_wake(puv3_rtc_alarmno);
    + else
    + disable_irq_wake(puv3_rtc_alarmno);
    +
    + return 0;
    +}
    +
    +static int puv3_rtc_proc(struct device *dev, struct seq_file *seq)
    +{
    + seq_printf(seq, "periodic_IRQ\t: %s\n",
    + (RTC_RTSR & RTC_RTSR_HZE) ? "yes" : "no");
    + return 0;
    +}
    +
    +static int puv3_rtc_open(struct device *dev)
    +{
    + struct platform_device *pdev = to_platform_device(dev);
    + struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
    + int ret;
    +
    + ret = request_irq(puv3_rtc_alarmno, puv3_rtc_alarmirq,
    + IRQF_DISABLED, "pkunity-rtc alarm", rtc_dev);
    +
    + if (ret) {
    + dev_err(dev, "IRQ%d error %d\n", puv3_rtc_alarmno, ret);
    + return ret;
    + }
    +
    + ret = request_irq(puv3_rtc_tickno, puv3_rtc_tickirq,
    + IRQF_DISABLED, "pkunity-rtc tick", rtc_dev);
    +
    + if (ret) {
    + dev_err(dev, "IRQ%d error %d\n", puv3_rtc_tickno, ret);
    + goto tick_err;
    + }
    +
    + return ret;
    +
    + tick_err:
    + free_irq(puv3_rtc_alarmno, rtc_dev);
    + return ret;
    +}
    +
    +static void puv3_rtc_release(struct device *dev)
    +{
    + struct platform_device *pdev = to_platform_device(dev);
    + struct rtc_device *rtc_dev = platform_get_drvdata(pdev);
    +
    + /* do not clear AIE here, it may be needed for wake */
    +
    + puv3_rtc_setpie(dev, 0);
    + free_irq(puv3_rtc_alarmno, rtc_dev);
    + free_irq(puv3_rtc_tickno, rtc_dev);
    +}
    +
    +static const struct rtc_class_ops puv3_rtcops = {
    + .open = puv3_rtc_open,
    + .release = puv3_rtc_release,
    + .read_time = puv3_rtc_gettime,
    + .set_time = puv3_rtc_settime,
    + .read_alarm = puv3_rtc_getalarm,
    + .set_alarm = puv3_rtc_setalarm,
    + .irq_set_freq = puv3_rtc_setfreq,
    + .irq_set_state = puv3_rtc_setpie,
    + .proc = puv3_rtc_proc,
    +};
    +
    +static void puv3_rtc_enable(struct platform_device *pdev, int en)
    +{
    + if (!en) {
    + RTC_RTSR &= ~RTC_RTSR_HZE;
    + } else {
    + /* re-enable the device, and check it is ok */
    +
    + if ((RTC_RTSR & RTC_RTSR_HZE) == 0) {
    + dev_info(&pdev->dev, "rtc disabled, re-enabling\n");
    + RTC_RTSR |= RTC_RTSR_HZE;
    + }
    + }
    +}
    +
    +static int puv3_rtc_remove(struct platform_device *dev)
    +{
    + struct rtc_device *rtc = platform_get_drvdata(dev);
    +
    + platform_set_drvdata(dev, NULL);
    + rtc_device_unregister(rtc);
    +
    + puv3_rtc_setpie(&dev->dev, 0);
    + puv3_rtc_setaie(0);
    +
    + release_resource(puv3_rtc_mem);
    + kfree(puv3_rtc_mem);
    +
    + return 0;
    +}
    +
    +static int puv3_rtc_probe(struct platform_device *pdev)
    +{
    + struct rtc_device *rtc;
    + struct resource *res;
    + int ret;
    +
    + pr_debug("%s: probe=%p\n", __func__, pdev);
    +
    + /* find the IRQs */
    +
    + puv3_rtc_tickno = platform_get_irq(pdev, 1);
    + if (puv3_rtc_tickno < 0) {
    + dev_err(&pdev->dev, "no irq for rtc tick\n");
    + return -ENOENT;
    + }
    +
    + puv3_rtc_alarmno = platform_get_irq(pdev, 0);
    + if (puv3_rtc_alarmno < 0) {
    + dev_err(&pdev->dev, "no irq for alarm\n");
    + return -ENOENT;
    + }
    +
    + pr_debug("PKUnity_rtc: tick irq %d, alarm irq %d\n",
    + puv3_rtc_tickno, puv3_rtc_alarmno);
    +
    + /* get the memory region */
    +
    + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    + if (res == NULL) {
    + dev_err(&pdev->dev, "failed to get memory region resource\n");
    + return -ENOENT;
    + }
    +
    + puv3_rtc_mem = request_mem_region(res->start,
    + res->end-res->start+1,
    + pdev->name);
    +
    + if (puv3_rtc_mem == NULL) {
    + dev_err(&pdev->dev, "failed to reserve memory region\n");
    + ret = -ENOENT;
    + goto err_nores;
    + }
    +
    + puv3_rtc_enable(pdev, 1);
    +
    + puv3_rtc_setfreq(&pdev->dev, 1);
    +
    + /* register RTC and exit */
    +
    + rtc = rtc_device_register("pkunity", &pdev->dev, &puv3_rtcops,
    + THIS_MODULE);
    +
    + if (IS_ERR(rtc)) {
    + dev_err(&pdev->dev, "cannot attach rtc\n");
    + ret = PTR_ERR(rtc);
    + goto err_nortc;
    + }
    +
    + /* platform setup code should have handled this; sigh */
    + if (!device_can_wakeup(&pdev->dev))
    + device_init_wakeup(&pdev->dev, 1);
    +
    + platform_set_drvdata(pdev, rtc);
    + return 0;
    +
    + err_nortc:
    + puv3_rtc_enable(pdev, 0);
    + release_resource(puv3_rtc_mem);
    +
    + err_nores:
    + return ret;
    +}
    +
    +#ifdef CONFIG_PM
    +
    +/* RTC Power management control */
    +
    +static int ticnt_save;
    +
    +static int puv3_rtc_suspend(struct platform_device *pdev, pm_message_t state)
    +{
    + /* save RTAR for anyone using periodic interrupts */
    + ticnt_save = RTC_RTAR;
    + puv3_rtc_enable(pdev, 0);
    + return 0;
    +}
    +
    +static int puv3_rtc_resume(struct platform_device *pdev)
    +{
    + puv3_rtc_enable(pdev, 1);
    + RTC_RTAR = ticnt_save;
    + return 0;
    +}
    +#else
    +#define puv3_rtc_suspend NULL
    +#define puv3_rtc_resume NULL
    +#endif
    +
    +static struct platform_driver puv3_rtcdrv = {
    + .probe = puv3_rtc_probe,
    + .remove = __devexit_p(puv3_rtc_remove),
    + .suspend = puv3_rtc_suspend,
    + .resume = puv3_rtc_resume,
    + .driver = {
    + .name = "PKUnity-v3-RTC",
    + .owner = THIS_MODULE,
    + }
    +};
    +
    +static char __initdata banner[] = "PKUnity-v3 RTC, (c) 2009 PKUnity Co.\n";
    +
    +static int __init puv3_rtc_init(void)
    +{
    + printk(banner);
    + return platform_driver_register(&puv3_rtcdrv);
    +}
    +
    +static void __exit puv3_rtc_exit(void)
    +{
    + platform_driver_unregister(&puv3_rtcdrv);
    +}
    +
    +module_init(puv3_rtc_init);
    +module_exit(puv3_rtc_exit);
    +
    +MODULE_DESCRIPTION("RTC Driver for the PKUnity v3 chip");
    +MODULE_AUTHOR("Hu Dongliang");
    +MODULE_LICENSE("GPL v2");
    +
    diff --git a/arch/unicore32/kernel/time.c b/arch/unicore32/kernel/time.c
    new file mode 100644
    index 0000000..8090d76
    --- /dev/null
    +++ b/arch/unicore32/kernel/time.c
    @@ -0,0 +1,148 @@
    +/*
    + * linux/arch/unicore32/kernel/time.c
    + *
    + * Code specific to PKUnity SoC and UniCore ISA
    + *
    + * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
    + * Copyright (C) 2001-2010 Guan Xuetao
    + *
    + * 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/init.h>
    +#include <linux/errno.h>
    +#include <linux/interrupt.h>
    +#include <linux/irq.h>
    +#include <linux/timex.h>
    +#include <linux/clockchips.h>
    +
    +#include <mach/hardware.h>
    +
    +#define MIN_OSCR_DELTA 2
    +
    +static irqreturn_t puv3_ost0_interrupt(int irq, void *dev_id)
    +{
    + struct clock_event_device *c = dev_id;
    +
    + /* Disarm the compare/match, signal the event. */
    + OST_OIER &= ~OST_OIER_E0;
    + OST_OSSR &= ~OST_OSSR_M0;
    + c->event_handler(c);
    +
    + return IRQ_HANDLED;
    +}
    +
    +static int
    +puv3_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c)
    +{
    + unsigned long next, oscr;
    +
    + OST_OIER |= OST_OIER_E0;
    + next = OST_OSCR + delta;
    + OST_OSMR0 = next;
    + oscr = OST_OSCR;
    +
    + return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
    +}
    +
    +static void
    +puv3_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c)
    +{
    + switch (mode) {
    + case CLOCK_EVT_MODE_ONESHOT:
    + case CLOCK_EVT_MODE_UNUSED:
    + case CLOCK_EVT_MODE_SHUTDOWN:
    + OST_OIER &= ~OST_OIER_E0;
    + OST_OSSR &= ~OST_OSSR_M0;
    + break;
    +
    + case CLOCK_EVT_MODE_RESUME:
    + case CLOCK_EVT_MODE_PERIODIC:
    + break;
    + }
    +}
    +
    +static struct clock_event_device ckevt_puv3_osmr0 = {
    + .name = "osmr0",
    + .features = CLOCK_EVT_FEAT_ONESHOT,
    +#ifdef CONFIG_ARCH_FPGA
    + .shift = 18, /* correct shift val: 16, but warn_on_slowpath */
    +#else
    + .shift = 30,
    +#endif
    + .rating = 200,
    + .set_next_event = puv3_osmr0_set_next_event,
    + .set_mode = puv3_osmr0_set_mode,
    +};
    +
    +static cycle_t puv3_read_oscr(struct clocksource *cs)
    +{
    + return OST_OSCR;
    +}
    +
    +static struct clocksource cksrc_puv3_oscr = {
    + .name = "oscr",
    + .rating = 200,
    + .read = puv3_read_oscr,
    + .mask = CLOCKSOURCE_MASK(32),
    + .flags = CLOCK_SOURCE_IS_CONTINUOUS,
    +};
    +
    +static struct irqaction puv3_timer_irq = {
    + .name = "ost0",
    + .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
    + .handler = puv3_ost0_interrupt,
    + .dev_id = &ckevt_puv3_osmr0,
    +};
    +
    +void __init time_init(void)
    +{
    + OST_OIER = 0; /* disable any timer interrupts */
    + OST_OSSR = 0; /* clear status on all timers */
    +
    + ckevt_puv3_osmr0.mult =
    + div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC, ckevt_puv3_osmr0.shift);
    + ckevt_puv3_osmr0.max_delta_ns =
    + clockevent_delta2ns(0x7fffffff, &ckevt_puv3_osmr0);
    + ckevt_puv3_osmr0.min_delta_ns =
    + clockevent_delta2ns(MIN_OSCR_DELTA * 2, &ckevt_puv3_osmr0) + 1;
    + ckevt_puv3_osmr0.cpumask = cpumask_of(0);
    +
    + setup_irq(IRQ_TIMER0, &puv3_timer_irq);
    +
    + clocksource_register_hz(&cksrc_puv3_oscr, CLOCK_TICK_RATE);
    + clockevents_register_device(&ckevt_puv3_osmr0);
    +}
    +
    +#ifdef CONFIG_PM
    +unsigned long osmr[4], oier;
    +
    +void puv3_timer_suspend(void)
    +{
    + osmr[0] = OST_OSMR0;
    + osmr[1] = OST_OSMR1;
    + osmr[2] = OST_OSMR2;
    + osmr[3] = OST_OSMR3;
    + oier = OST_OIER;
    +}
    +
    +void puv3_timer_resume(void)
    +{
    + OST_OSSR = 0;
    + OST_OSMR0 = osmr[0];
    + OST_OSMR1 = osmr[1];
    + OST_OSMR2 = osmr[2];
    + OST_OSMR3 = osmr[3];
    + OST_OIER = oier;
    +
    + /*
    + * OSMR0 is the system timer: make sure OSCR is sufficiently behind
    + */
    + OST_OSCR = OST_OSMR0 - LATCH;
    +}
    +#else
    +void puv3_timer_suspend(void) { };
    +void puv3_timer_resume(void) { };
    +#endif
    +
    --
    1.7.0.4



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