418 lines
9.5 KiB
C
418 lines
9.5 KiB
C
/*
|
|
* EFI Time Services Driver for Linux
|
|
*
|
|
* Copyright (C) 1999 Hewlett-Packard Co
|
|
* Copyright (C) 1999 Stephane Eranian <eranian@hpl.hp.com>
|
|
*
|
|
* Based on skeleton from the drivers/char/rtc.c driver by P. Gortmaker
|
|
*
|
|
* This code provides an architected & portable interface to the real time
|
|
* clock by using EFI instead of direct bit fiddling. The functionalities are
|
|
* quite different from the rtc.c driver. The only way to talk to the device
|
|
* is by using ioctl(). There is a /proc interface which provides the raw
|
|
* information.
|
|
*
|
|
* Please note that we have kept the API as close as possible to the
|
|
* legacy RTC. The standard /sbin/hwclock program should work normally
|
|
* when used to get/set the time.
|
|
*
|
|
* NOTES:
|
|
* - Locking is required for safe execution of EFI calls with regards
|
|
* to interrupts and SMP.
|
|
*
|
|
* TODO (December 1999):
|
|
* - provide the API to set/get the WakeUp Alarm (different from the
|
|
* rtc.c alarm).
|
|
* - SMP testing
|
|
* - Add module support
|
|
*/
|
|
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/miscdevice.h>
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/efi.h>
|
|
|
|
#include <asm/uaccess.h>
|
|
#include <asm/system.h>
|
|
|
|
#define EFI_RTC_VERSION "0.4"
|
|
|
|
#define EFI_ISDST (EFI_TIME_ADJUST_DAYLIGHT|EFI_TIME_IN_DAYLIGHT)
|
|
/*
|
|
* EFI Epoch is 1/1/1998
|
|
*/
|
|
#define EFI_RTC_EPOCH 1998
|
|
|
|
static DEFINE_SPINLOCK(efi_rtc_lock);
|
|
|
|
static int efi_rtc_ioctl(struct inode *inode, struct file *file,
|
|
unsigned int cmd, unsigned long arg);
|
|
|
|
#define is_leap(year) \
|
|
((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
|
|
|
|
static const unsigned short int __mon_yday[2][13] =
|
|
{
|
|
/* Normal years. */
|
|
{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
|
|
/* Leap years. */
|
|
{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
|
|
};
|
|
|
|
/*
|
|
* returns day of the year [0-365]
|
|
*/
|
|
static inline int
|
|
compute_yday(efi_time_t *eft)
|
|
{
|
|
/* efi_time_t.month is in the [1-12] so, we need -1 */
|
|
return __mon_yday[is_leap(eft->year)][eft->month-1]+ eft->day -1;
|
|
}
|
|
/*
|
|
* returns day of the week [0-6] 0=Sunday
|
|
*
|
|
* Don't try to provide a year that's before 1998, please !
|
|
*/
|
|
static int
|
|
compute_wday(efi_time_t *eft)
|
|
{
|
|
int y;
|
|
int ndays = 0;
|
|
|
|
if ( eft->year < 1998 ) {
|
|
printk(KERN_ERR "efirtc: EFI year < 1998, invalid date\n");
|
|
return -1;
|
|
}
|
|
|
|
for(y=EFI_RTC_EPOCH; y < eft->year; y++ ) {
|
|
ndays += 365 + (is_leap(y) ? 1 : 0);
|
|
}
|
|
ndays += compute_yday(eft);
|
|
|
|
/*
|
|
* 4=1/1/1998 was a Thursday
|
|
*/
|
|
return (ndays + 4) % 7;
|
|
}
|
|
|
|
static void
|
|
convert_to_efi_time(struct rtc_time *wtime, efi_time_t *eft)
|
|
{
|
|
|
|
eft->year = wtime->tm_year + 1900;
|
|
eft->month = wtime->tm_mon + 1;
|
|
eft->day = wtime->tm_mday;
|
|
eft->hour = wtime->tm_hour;
|
|
eft->minute = wtime->tm_min;
|
|
eft->second = wtime->tm_sec;
|
|
eft->nanosecond = 0;
|
|
eft->daylight = wtime->tm_isdst ? EFI_ISDST: 0;
|
|
eft->timezone = EFI_UNSPECIFIED_TIMEZONE;
|
|
}
|
|
|
|
static void
|
|
convert_from_efi_time(efi_time_t *eft, struct rtc_time *wtime)
|
|
{
|
|
memset(wtime, 0, sizeof(*wtime));
|
|
wtime->tm_sec = eft->second;
|
|
wtime->tm_min = eft->minute;
|
|
wtime->tm_hour = eft->hour;
|
|
wtime->tm_mday = eft->day;
|
|
wtime->tm_mon = eft->month - 1;
|
|
wtime->tm_year = eft->year - 1900;
|
|
|
|
/* day of the week [0-6], Sunday=0 */
|
|
wtime->tm_wday = compute_wday(eft);
|
|
|
|
/* day in the year [1-365]*/
|
|
wtime->tm_yday = compute_yday(eft);
|
|
|
|
|
|
switch (eft->daylight & EFI_ISDST) {
|
|
case EFI_ISDST:
|
|
wtime->tm_isdst = 1;
|
|
break;
|
|
case EFI_TIME_ADJUST_DAYLIGHT:
|
|
wtime->tm_isdst = 0;
|
|
break;
|
|
default:
|
|
wtime->tm_isdst = -1;
|
|
}
|
|
}
|
|
|
|
static int
|
|
efi_rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
|
|
efi_status_t status;
|
|
unsigned long flags;
|
|
efi_time_t eft;
|
|
efi_time_cap_t cap;
|
|
struct rtc_time wtime;
|
|
struct rtc_wkalrm __user *ewp;
|
|
unsigned char enabled, pending;
|
|
|
|
switch (cmd) {
|
|
case RTC_UIE_ON:
|
|
case RTC_UIE_OFF:
|
|
case RTC_PIE_ON:
|
|
case RTC_PIE_OFF:
|
|
case RTC_AIE_ON:
|
|
case RTC_AIE_OFF:
|
|
case RTC_ALM_SET:
|
|
case RTC_ALM_READ:
|
|
case RTC_IRQP_READ:
|
|
case RTC_IRQP_SET:
|
|
case RTC_EPOCH_READ:
|
|
case RTC_EPOCH_SET:
|
|
return -EINVAL;
|
|
|
|
case RTC_RD_TIME:
|
|
|
|
spin_lock_irqsave(&efi_rtc_lock, flags);
|
|
|
|
status = efi.get_time(&eft, &cap);
|
|
|
|
spin_unlock_irqrestore(&efi_rtc_lock,flags);
|
|
|
|
if (status != EFI_SUCCESS) {
|
|
/* should never happen */
|
|
printk(KERN_ERR "efitime: can't read time\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
convert_from_efi_time(&eft, &wtime);
|
|
|
|
return copy_to_user((void __user *)arg, &wtime,
|
|
sizeof (struct rtc_time)) ? - EFAULT : 0;
|
|
|
|
case RTC_SET_TIME:
|
|
|
|
if (!capable(CAP_SYS_TIME)) return -EACCES;
|
|
|
|
if (copy_from_user(&wtime, (struct rtc_time __user *)arg,
|
|
sizeof(struct rtc_time)) )
|
|
return -EFAULT;
|
|
|
|
convert_to_efi_time(&wtime, &eft);
|
|
|
|
spin_lock_irqsave(&efi_rtc_lock, flags);
|
|
|
|
status = efi.set_time(&eft);
|
|
|
|
spin_unlock_irqrestore(&efi_rtc_lock,flags);
|
|
|
|
return status == EFI_SUCCESS ? 0 : -EINVAL;
|
|
|
|
case RTC_WKALM_SET:
|
|
|
|
if (!capable(CAP_SYS_TIME)) return -EACCES;
|
|
|
|
ewp = (struct rtc_wkalrm __user *)arg;
|
|
|
|
if ( get_user(enabled, &ewp->enabled)
|
|
|| copy_from_user(&wtime, &ewp->time, sizeof(struct rtc_time)) )
|
|
return -EFAULT;
|
|
|
|
convert_to_efi_time(&wtime, &eft);
|
|
|
|
spin_lock_irqsave(&efi_rtc_lock, flags);
|
|
/*
|
|
* XXX Fixme:
|
|
* As of EFI 0.92 with the firmware I have on my
|
|
* machine this call does not seem to work quite
|
|
* right
|
|
*/
|
|
status = efi.set_wakeup_time((efi_bool_t)enabled, &eft);
|
|
|
|
spin_unlock_irqrestore(&efi_rtc_lock,flags);
|
|
|
|
return status == EFI_SUCCESS ? 0 : -EINVAL;
|
|
|
|
case RTC_WKALM_RD:
|
|
|
|
spin_lock_irqsave(&efi_rtc_lock, flags);
|
|
|
|
status = efi.get_wakeup_time((efi_bool_t *)&enabled, (efi_bool_t *)&pending, &eft);
|
|
|
|
spin_unlock_irqrestore(&efi_rtc_lock,flags);
|
|
|
|
if (status != EFI_SUCCESS) return -EINVAL;
|
|
|
|
ewp = (struct rtc_wkalrm __user *)arg;
|
|
|
|
if ( put_user(enabled, &ewp->enabled)
|
|
|| put_user(pending, &ewp->pending)) return -EFAULT;
|
|
|
|
convert_from_efi_time(&eft, &wtime);
|
|
|
|
return copy_to_user(&ewp->time, &wtime,
|
|
sizeof(struct rtc_time)) ? -EFAULT : 0;
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* We enforce only one user at a time here with the open/close.
|
|
* Also clear the previous interrupt data on an open, and clean
|
|
* up things on a close.
|
|
*/
|
|
|
|
static int
|
|
efi_rtc_open(struct inode *inode, struct file *file)
|
|
{
|
|
/*
|
|
* nothing special to do here
|
|
* We do accept multiple open files at the same time as we
|
|
* synchronize on the per call operation.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
efi_rtc_close(struct inode *inode, struct file *file)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* The various file operations we support.
|
|
*/
|
|
|
|
static const struct file_operations efi_rtc_fops = {
|
|
.owner = THIS_MODULE,
|
|
.ioctl = efi_rtc_ioctl,
|
|
.open = efi_rtc_open,
|
|
.release = efi_rtc_close,
|
|
};
|
|
|
|
static struct miscdevice efi_rtc_dev=
|
|
{
|
|
EFI_RTC_MINOR,
|
|
"efirtc",
|
|
&efi_rtc_fops
|
|
};
|
|
|
|
/*
|
|
* We export RAW EFI information to /proc/driver/efirtc
|
|
*/
|
|
static int
|
|
efi_rtc_get_status(char *buf)
|
|
{
|
|
efi_time_t eft, alm;
|
|
efi_time_cap_t cap;
|
|
char *p = buf;
|
|
efi_bool_t enabled, pending;
|
|
unsigned long flags;
|
|
|
|
memset(&eft, 0, sizeof(eft));
|
|
memset(&alm, 0, sizeof(alm));
|
|
memset(&cap, 0, sizeof(cap));
|
|
|
|
spin_lock_irqsave(&efi_rtc_lock, flags);
|
|
|
|
efi.get_time(&eft, &cap);
|
|
efi.get_wakeup_time(&enabled, &pending, &alm);
|
|
|
|
spin_unlock_irqrestore(&efi_rtc_lock,flags);
|
|
|
|
p += sprintf(p,
|
|
"Time : %u:%u:%u.%09u\n"
|
|
"Date : %u-%u-%u\n"
|
|
"Daylight : %u\n",
|
|
eft.hour, eft.minute, eft.second, eft.nanosecond,
|
|
eft.year, eft.month, eft.day,
|
|
eft.daylight);
|
|
|
|
if (eft.timezone == EFI_UNSPECIFIED_TIMEZONE)
|
|
p += sprintf(p, "Timezone : unspecified\n");
|
|
else
|
|
/* XXX fixme: convert to string? */
|
|
p += sprintf(p, "Timezone : %u\n", eft.timezone);
|
|
|
|
|
|
p += sprintf(p,
|
|
"Alarm Time : %u:%u:%u.%09u\n"
|
|
"Alarm Date : %u-%u-%u\n"
|
|
"Alarm Daylight : %u\n"
|
|
"Enabled : %s\n"
|
|
"Pending : %s\n",
|
|
alm.hour, alm.minute, alm.second, alm.nanosecond,
|
|
alm.year, alm.month, alm.day,
|
|
alm.daylight,
|
|
enabled == 1 ? "yes" : "no",
|
|
pending == 1 ? "yes" : "no");
|
|
|
|
if (eft.timezone == EFI_UNSPECIFIED_TIMEZONE)
|
|
p += sprintf(p, "Timezone : unspecified\n");
|
|
else
|
|
/* XXX fixme: convert to string? */
|
|
p += sprintf(p, "Timezone : %u\n", alm.timezone);
|
|
|
|
/*
|
|
* now prints the capabilities
|
|
*/
|
|
p += sprintf(p,
|
|
"Resolution : %u\n"
|
|
"Accuracy : %u\n"
|
|
"SetstoZero : %u\n",
|
|
cap.resolution, cap.accuracy, cap.sets_to_zero);
|
|
|
|
return p - buf;
|
|
}
|
|
|
|
static int
|
|
efi_rtc_read_proc(char *page, char **start, off_t off,
|
|
int count, int *eof, void *data)
|
|
{
|
|
int len = efi_rtc_get_status(page);
|
|
if (len <= off+count) *eof = 1;
|
|
*start = page + off;
|
|
len -= off;
|
|
if (len>count) len = count;
|
|
if (len<0) len = 0;
|
|
return len;
|
|
}
|
|
|
|
static int __init
|
|
efi_rtc_init(void)
|
|
{
|
|
int ret;
|
|
struct proc_dir_entry *dir;
|
|
|
|
printk(KERN_INFO "EFI Time Services Driver v%s\n", EFI_RTC_VERSION);
|
|
|
|
ret = misc_register(&efi_rtc_dev);
|
|
if (ret) {
|
|
printk(KERN_ERR "efirtc: can't misc_register on minor=%d\n",
|
|
EFI_RTC_MINOR);
|
|
return ret;
|
|
}
|
|
|
|
dir = create_proc_read_entry ("driver/efirtc", 0, NULL,
|
|
efi_rtc_read_proc, NULL);
|
|
if (dir == NULL) {
|
|
printk(KERN_ERR "efirtc: can't create /proc/driver/efirtc.\n");
|
|
misc_deregister(&efi_rtc_dev);
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void __exit
|
|
efi_rtc_exit(void)
|
|
{
|
|
/* not yet used */
|
|
}
|
|
|
|
module_init(efi_rtc_init);
|
|
module_exit(efi_rtc_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|