MIPS: Convert update_persistent_clock() to update_persistent_clock64()

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@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Signed-off-by: James Hogan <jhogan@kernel.org>

diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c
index 9e992cf1129e51517e6a2fda6a4bd585177673c9..c38686f89a1883d954ff3cb7044350c8d559edba 100644 (file)
--- 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 17d4cd20f18c1498ac3416267f31980a56f54245..b85ec64ee7e98a067cf2dc4c35b1dc04411e02cc 100644 (file)
--- a/arch/mips/include/asm/time.h
+++ b/arch/mips/include/asm/time.h
@@ -21,15 +21,6 @@
 
 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().
  */

diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
index a6ebc8135112e5c9c22e5598bf25556469f9dbb4..bfe02ded25d1f338db56376c3097871948781a24 100644 (file)
--- 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 d75c8875a643f771f73de0f0456bb3fc1bc50c7a..e6ce39fefa784729d2f46e8ee0298271fb72e558 100644 (file)
--- 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 6f7422400f32aeaca60fc887fcb7d8132b7d9a69..ead07c243c6a2e9db2ba39a4698043e2602a2bab 100644 (file)
--- 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 aa27a2226472a13f206a449469f7aca41a9581b9..4ac8ccdf56bba2b2d365893722f1e9f9c8069309 100644 (file)
--- 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 a2121c1345a9fa7f407e2685eb39579ac70ed9bc..2dcaaa7e3bfa2babd0bbf4cd2802c428d46a504d 100644 (file)
--- 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 7073940c02bffedaf55cd2bdb4987e7657d60cdb..152ca71cc2d7b97a6c17a4f4aa7cb3fdd7dd7ad8 100644 (file)
--- a/arch/mips/sibyte/swarm/setup.c
+++ b/arch/mips/sibyte/swarm/setup.c
@@ -57,11 +57,11 @@ extern void sb1250_setup(void);
 #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);