[PATCH v3 2/2] MIPS: Convert update_persistent_clock() to update_persistent_clock64()
From: Baolin Wang
Date: Mon May 07 2018 - 05:30:11 EST
Since struct timespec is not y2038 safe on 32bit machines, this patch
converts update_persistent_clock() to update_persistent_clock64() using
struct timespec64.
The rtc_mips_set_time() and rtc_mips_set_mmss() interfaces were using
'unsigned long' type that is not y2038 safe on 32bit machines, moreover
there is only one platform implementing rtc_mips_set_time() and two
platforms implementing rtc_mips_set_mmss(), so we can just make them each
implement update_persistent_clock64() directly, to get that helper out
of the common mips code by removing rtc_mips_set_time() and
rtc_mips_set_mmss() interfaces.
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
---
Changes since v2:
- Use div_u64_rem() to calculate the min/sec.
- Add some comments.
Changes since v1:
- Remove rtc_mips_set_time() and rtc_mips_set_mmss() interfaces.
---
arch/mips/dec/time.c | 8 ++++----
arch/mips/include/asm/time.h | 9 ---------
arch/mips/kernel/time.c | 15 ---------------
arch/mips/lasat/ds1603.c | 9 +++++++--
arch/mips/lasat/sysctl.c | 12 ++++++++++--
arch/mips/sibyte/swarm/rtc_m41t81.c | 4 ++--
arch/mips/sibyte/swarm/rtc_xicor1241.c | 4 ++--
arch/mips/sibyte/swarm/setup.c | 8 +++++---
8 files changed, 30 insertions(+), 39 deletions(-)
diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c
index 9e992cf..c38686f 100644
--- a/arch/mips/dec/time.c
+++ b/arch/mips/dec/time.c
@@ -59,14 +59,15 @@ void read_persistent_clock64(struct timespec64 *ts)
}
/*
- * In order to set the CMOS clock precisely, rtc_mips_set_mmss has to
+ * In order to set the CMOS clock precisely, update_persistent_clock64 has to
* be called 500 ms after the second nowtime has started, because when
* nowtime is written into the registers of the CMOS clock, it will
* jump to the next second precisely 500 ms later. Check the Dallas
* DS1287 data sheet for details.
*/
-int rtc_mips_set_mmss(unsigned long nowtime)
+int update_persistent_clock64(struct timespec64 now)
{
+ time64_t nowtime = now.tv_sec;
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
unsigned char save_control, save_freq_select;
@@ -91,8 +92,7 @@ int rtc_mips_set_mmss(unsigned long nowtime)
* messing with unknown time zones but requires your
* RTC not to be off by more than 15 minutes
*/
- real_seconds = nowtime % 60;
- real_minutes = nowtime / 60;
+ real_minutes = div_s64_rem(nowtime, 60, &real_seconds);
if (((abs(real_minutes - cmos_minutes) + 15) / 30) & 1)
real_minutes += 30; /* correct for half hour time zone */
real_minutes %= 60;
diff --git a/arch/mips/include/asm/time.h b/arch/mips/include/asm/time.h
index 17d4cd2..b85ec64 100644
--- a/arch/mips/include/asm/time.h
+++ b/arch/mips/include/asm/time.h
@@ -22,15 +22,6 @@
extern spinlock_t rtc_lock;
/*
- * RTC ops. By default, they point to weak no-op RTC functions.
- * rtc_mips_set_time - reverse the above translation and set time to RTC.
- * rtc_mips_set_mmss - similar to rtc_set_time, but only min and sec need
- * to be set. Used by RTC sync-up.
- */
-extern int rtc_mips_set_time(unsigned long);
-extern int rtc_mips_set_mmss(unsigned long);
-
-/*
* board specific routines required by time_init().
*/
extern void plat_time_init(void);
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
index a6ebc81..bfe02de 100644
--- a/arch/mips/kernel/time.c
+++ b/arch/mips/kernel/time.c
@@ -34,21 +34,6 @@
DEFINE_SPINLOCK(rtc_lock);
EXPORT_SYMBOL(rtc_lock);
-int __weak rtc_mips_set_time(unsigned long sec)
-{
- return -ENODEV;
-}
-
-int __weak rtc_mips_set_mmss(unsigned long nowtime)
-{
- return rtc_mips_set_time(nowtime);
-}
-
-int update_persistent_clock(struct timespec now)
-{
- return rtc_mips_set_mmss(now.tv_sec);
-}
-
static int null_perf_irq(void)
{
return 0;
diff --git a/arch/mips/lasat/ds1603.c b/arch/mips/lasat/ds1603.c
index d75c887..e6ce39f 100644
--- a/arch/mips/lasat/ds1603.c
+++ b/arch/mips/lasat/ds1603.c
@@ -152,14 +152,19 @@ void read_persistent_clock64(struct timespec64 *ts)
ts->tv_nsec = 0;
}
-int rtc_mips_set_mmss(unsigned long time)
+int update_persistent_clock64(struct timespec64 now)
{
+ time64_t time = now.tv_sec;
unsigned long flags;
spin_lock_irqsave(&rtc_lock, flags);
rtc_init_op();
rtc_write_byte(SET_TIME_CMD);
- rtc_write_word(time);
+ /*
+ * Due to the hardware limitation, we cast to 'unsigned long' type,
+ * so it will overflow in year 2106 on 32-bit machine.
+ */
+ rtc_write_word((unsigned long)time);
rtc_end_op();
spin_unlock_irqrestore(&rtc_lock, flags);
diff --git a/arch/mips/lasat/sysctl.c b/arch/mips/lasat/sysctl.c
index 6f74224..ead07c2 100644
--- a/arch/mips/lasat/sysctl.c
+++ b/arch/mips/lasat/sysctl.c
@@ -73,8 +73,16 @@ int proc_dolasatrtc(struct ctl_table *table, int write,
if (r)
return r;
- if (write)
- rtc_mips_set_mmss(rtctmp);
+ if (write) {
+ /*
+ * Due to the RTC hardware limitation, we can not actually
+ * use the full 64-bit range here.
+ */
+ ts.tv_sec = rtctmp;
+ ts.tv_nsec = 0;
+
+ update_persistent_clock64(ts);
+ }
return 0;
}
diff --git a/arch/mips/sibyte/swarm/rtc_m41t81.c b/arch/mips/sibyte/swarm/rtc_m41t81.c
index aa27a22..4ac8ccd 100644
--- a/arch/mips/sibyte/swarm/rtc_m41t81.c
+++ b/arch/mips/sibyte/swarm/rtc_m41t81.c
@@ -141,13 +141,13 @@ static int m41t81_write(uint8_t addr, int b)
return 0;
}
-int m41t81_set_time(unsigned long t)
+int m41t81_set_time(time64_t t)
{
struct rtc_time tm;
unsigned long flags;
/* Note we don't care about the century */
- rtc_time_to_tm(t, &tm);
+ rtc_time64_to_tm(t, &tm);
/*
* Note the write order matters as it ensures the correctness.
diff --git a/arch/mips/sibyte/swarm/rtc_xicor1241.c b/arch/mips/sibyte/swarm/rtc_xicor1241.c
index a2121c1..2dcaaa7 100644
--- a/arch/mips/sibyte/swarm/rtc_xicor1241.c
+++ b/arch/mips/sibyte/swarm/rtc_xicor1241.c
@@ -109,13 +109,13 @@ static int xicor_write(uint8_t addr, int b)
}
}
-int xicor_set_time(unsigned long t)
+int xicor_set_time(time64_t t)
{
struct rtc_time tm;
int tmp;
unsigned long flags;
- rtc_time_to_tm(t, &tm);
+ rtc_time64_to_tm(t, &tm);
tm.tm_year += 1900;
spin_lock_irqsave(&rtc_lock, flags);
diff --git a/arch/mips/sibyte/swarm/setup.c b/arch/mips/sibyte/swarm/setup.c
index 7073940..152ca71 100644
--- a/arch/mips/sibyte/swarm/setup.c
+++ b/arch/mips/sibyte/swarm/setup.c
@@ -57,11 +57,11 @@
#endif
extern int xicor_probe(void);
-extern int xicor_set_time(unsigned long);
+extern int xicor_set_time(time64_t);
extern time64_t xicor_get_time(void);
extern int m41t81_probe(void);
-extern int m41t81_set_time(unsigned long);
+extern int m41t81_set_time(time64_t);
extern time64_t m41t81_get_time(void);
const char *get_system_type(void)
@@ -109,8 +109,10 @@ void read_persistent_clock64(struct timespec64 *ts)
ts->tv_nsec = 0;
}
-int rtc_mips_set_time(unsigned long sec)
+int update_persistent_clock64(struct timespec64 now)
{
+ time64_t sec = now.tv_sec;
+
switch (swarm_rtc_type) {
case RTC_XICOR:
return xicor_set_time(sec);
--
1.7.9.5