linux-stable/arch/powerpc/kernel/rtas-rtc.c
Michael Neuling 0e8ed47912 [PATCH] powerpc: RTC memory corruption
We should be memset'ing the data we are pointing to, not the pointer
itself.  This is in an error path so we probably don't hit it much.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-16 16:55:03 +11:00

105 lines
3 KiB
C

#include <linux/kernel.h>
#include <linux/time.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <linux/rtc.h>
#include <linux/delay.h>
#include <asm/prom.h>
#include <asm/rtas.h>
#include <asm/time.h>
#define MAX_RTC_WAIT 5000 /* 5 sec */
#define RTAS_CLOCK_BUSY (-2)
unsigned long __init rtas_get_boot_time(void)
{
int ret[8];
int error, wait_time;
u64 max_wait_tb;
max_wait_tb = get_tb() + tb_ticks_per_usec * 1000 * MAX_RTC_WAIT;
do {
error = rtas_call(rtas_token("get-time-of-day"), 0, 8, ret);
if (error == RTAS_CLOCK_BUSY || rtas_is_extended_busy(error)) {
wait_time = rtas_extended_busy_delay_time(error);
/* This is boot time so we spin. */
udelay(wait_time*1000);
error = RTAS_CLOCK_BUSY;
}
} while (error == RTAS_CLOCK_BUSY && (get_tb() < max_wait_tb));
if (error != 0 && printk_ratelimit()) {
printk(KERN_WARNING "error: reading the clock failed (%d)\n",
error);
return 0;
}
return mktime(ret[0], ret[1], ret[2], ret[3], ret[4], ret[5]);
}
/* NOTE: get_rtc_time will get an error if executed in interrupt context
* and if a delay is needed to read the clock. In this case we just
* silently return without updating rtc_tm.
*/
void rtas_get_rtc_time(struct rtc_time *rtc_tm)
{
int ret[8];
int error, wait_time;
u64 max_wait_tb;
max_wait_tb = get_tb() + tb_ticks_per_usec * 1000 * MAX_RTC_WAIT;
do {
error = rtas_call(rtas_token("get-time-of-day"), 0, 8, ret);
if (error == RTAS_CLOCK_BUSY || rtas_is_extended_busy(error)) {
if (in_interrupt() && printk_ratelimit()) {
memset(rtc_tm, 0, sizeof(struct rtc_time));
printk(KERN_WARNING "error: reading clock"
" would delay interrupt\n");
return; /* delay not allowed */
}
wait_time = rtas_extended_busy_delay_time(error);
msleep(wait_time);
error = RTAS_CLOCK_BUSY;
}
} while (error == RTAS_CLOCK_BUSY && (get_tb() < max_wait_tb));
if (error != 0 && printk_ratelimit()) {
printk(KERN_WARNING "error: reading the clock failed (%d)\n",
error);
return;
}
rtc_tm->tm_sec = ret[5];
rtc_tm->tm_min = ret[4];
rtc_tm->tm_hour = ret[3];
rtc_tm->tm_mday = ret[2];
rtc_tm->tm_mon = ret[1] - 1;
rtc_tm->tm_year = ret[0] - 1900;
}
int rtas_set_rtc_time(struct rtc_time *tm)
{
int error, wait_time;
u64 max_wait_tb;
max_wait_tb = get_tb() + tb_ticks_per_usec * 1000 * MAX_RTC_WAIT;
do {
error = rtas_call(rtas_token("set-time-of-day"), 7, 1, NULL,
tm->tm_year + 1900, tm->tm_mon + 1,
tm->tm_mday, tm->tm_hour, tm->tm_min,
tm->tm_sec, 0);
if (error == RTAS_CLOCK_BUSY || rtas_is_extended_busy(error)) {
if (in_interrupt())
return 1; /* probably decrementer */
wait_time = rtas_extended_busy_delay_time(error);
msleep(wait_time);
error = RTAS_CLOCK_BUSY;
}
} while (error == RTAS_CLOCK_BUSY && (get_tb() < max_wait_tb));
if (error != 0 && printk_ratelimit())
printk(KERN_WARNING "error: setting the clock failed (%d)\n",
error);
return 0;
}