diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rtc/rtc-sun4v.c | 153 |
3 files changed, 161 insertions, 0 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 5d600ff..23403fa 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -592,4 +592,11 @@ config RTC_DRV_PPC the RTC. This exposes that functionality through the generic RTC class. +config RTC_DRV_SUN4V + bool "SUN4V Hypervisor RTC" + depends on SPARC64 + help + If you say Y here you will get support for the Hypervisor + based RTC on SUN4V systems. + endif # RTC_CLASS diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index fed42c2..6850b04 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_RTC_DRV_M41T94) += rtc-m41t94.o obj-$(CONFIG_RTC_DRV_M48T59) += rtc-m48t59.o obj-$(CONFIG_RTC_DRV_M48T86) += rtc-m48t86.o obj-$(CONFIG_RTC_DRV_BQ4802) += rtc-bq4802.o +obj-$(CONFIG_RTC_DRV_SUN4V) += rtc-sun4v.o obj-$(CONFIG_RTC_DRV_MAX6900) += rtc-max6900.o obj-$(CONFIG_RTC_DRV_MAX6902) += rtc-max6902.o obj-$(CONFIG_RTC_DRV_OMAP) += rtc-omap.o diff --git a/drivers/rtc/rtc-sun4v.c b/drivers/rtc/rtc-sun4v.c new file mode 100644 index 0000000..2012ccb --- /dev/null +++ b/drivers/rtc/rtc-sun4v.c @@ -0,0 +1,153 @@ +/* rtc-sun4c.c: Hypervisor based RTC for SUN4V systems. + * + * Copyright (C) 2008 David S. Miller <davem@davemloft.net> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/time.h> +#include <linux/rtc.h> +#include <linux/platform_device.h> + +#include <asm/hypervisor.h> + +MODULE_AUTHOR("David S. Miller <davem@davemloft.net>"); +MODULE_DESCRIPTION("SUN4V RTC driver"); +MODULE_LICENSE("GPL"); + +struct sun4v_rtc { + struct rtc_device *rtc; + spinlock_t lock; +}; + +static unsigned long hypervisor_get_time(void) +{ + unsigned long ret, time; + int retries = 10000; + +retry: + ret = sun4v_tod_get(&time); + if (ret == HV_EOK) + return time; + if (ret == HV_EWOULDBLOCK) { + if (--retries > 0) { + udelay(100); + goto retry; + } + printk(KERN_WARNING "SUN4V: tod_get() timed out.\n"); + return 0; + } + printk(KERN_WARNING "SUN4V: tod_get() not supported.\n"); + return 0; +} + +static int sun4v_read_time(struct device *dev, struct rtc_time *tm) +{ + struct sun4v_rtc *p = dev_get_drvdata(dev); + unsigned long flags, secs; + + spin_lock_irqsave(&p->lock, flags); + secs = hypervisor_get_time(); + spin_unlock_irqrestore(&p->lock, flags); + + rtc_time_to_tm(secs, tm); + + return 0; +} + +static int hypervisor_set_time(unsigned long secs) +{ + unsigned long ret; + int retries = 10000; + +retry: + ret = sun4v_tod_set(secs); + if (ret == HV_EOK) + return 0; + if (ret == HV_EWOULDBLOCK) { + if (--retries > 0) { + udelay(100); + goto retry; + } + printk(KERN_WARNING "SUN4V: tod_set() timed out.\n"); + return -EAGAIN; + } + printk(KERN_WARNING "SUN4V: tod_set() not supported.\n"); + return -EOPNOTSUPP; +} + +static int sun4v_set_time(struct device *dev, struct rtc_time *tm) +{ + struct sun4v_rtc *p = dev_get_drvdata(dev); + unsigned long flags, secs; + int err; + + err = rtc_tm_to_time(tm, &secs); + if (err) + return err; + + spin_lock_irqsave(&p->lock, flags); + err = hypervisor_set_time(secs); + spin_unlock_irqrestore(&p->lock, flags); + + return err; +} + +static const struct rtc_class_ops sun4v_rtc_ops = { + .read_time = sun4v_read_time, + .set_time = sun4v_set_time, +}; + +static int __devinit sun4v_rtc_probe(struct platform_device *pdev) +{ + struct sun4v_rtc *p = kzalloc(sizeof(*p), GFP_KERNEL); + + if (!p) + return -ENOMEM; + + spin_lock_init(&p->lock); + + p->rtc = rtc_device_register("sun4v", &pdev->dev, + &sun4v_rtc_ops, THIS_MODULE); + if (IS_ERR(p->rtc)) { + int err = PTR_ERR(p->rtc); + kfree(p); + return err; + } + platform_set_drvdata(pdev, p); + return 0; +} + +static int __devexit sun4v_rtc_remove(struct platform_device *pdev) +{ + struct sun4v_rtc *p = platform_get_drvdata(pdev); + + rtc_device_unregister(p->rtc); + kfree(p); + + return 0; +} + +static struct platform_driver sun4v_rtc_driver = { + .driver = { + .name = "rtc-sun4v", + .owner = THIS_MODULE, + }, + .probe = sun4v_rtc_probe, + .remove = __devexit_p(sun4v_rtc_remove), +}; + +static int __init sun4v_rtc_init(void) +{ + return platform_driver_register(&sun4v_rtc_driver); +} + +static void __exit sun4v_rtc_exit(void) +{ + platform_driver_unregister(&sun4v_rtc_driver); +} + +module_init(sun4v_rtc_init); +module_exit(sun4v_rtc_exit); |