macintosh: Use common code to access RTC

Now that the 68k Mac port has adopted the via-pmu driver, the same RTC
code can be shared between m68k and powerpc. Replace duplicated code in
arch/powerpc and arch/m68k with common RTC accessors for Cuda and PMU.

Drop the problematic WARN_ON which was introduced in commit 22db552b50fa
("powerpc/powermac: Fix rtc read/write functions").

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/m68k/mac/misc.c

@@ -37,35 +37,6 @@
 static void (*rom_reset)(void);
 
 #ifdef CONFIG_ADB_CUDA
-static time64_t cuda_read_time(void)
-{
-	struct adb_request req;
-	time64_t time;
-
-	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
-		return 0;
-	while (!req.complete)
-		cuda_poll();
-
-	time = (u32)((req.reply[3] << 24) | (req.reply[4] << 16) |
-		     (req.reply[5] << 8) | req.reply[6]);
-
-	return time - RTC_OFFSET;
-}
-
-static void cuda_write_time(time64_t time)
-{
-	struct adb_request req;
-	u32 data = lower_32_bits(time + RTC_OFFSET);
-
-	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
-			 (data >> 24) & 0xFF, (data >> 16) & 0xFF,
-			 (data >> 8) & 0xFF, data & 0xFF) < 0)
-		return;
-	while (!req.complete)
-		cuda_poll();
-}
-
 static __u8 cuda_read_pram(int offset)
 {
 	struct adb_request req;
@@ -91,33 +62,6 @@ static void cuda_write_pram(int offset, __u8 data)
 #endif /* CONFIG_ADB_CUDA */
 
 #ifdef CONFIG_ADB_PMU
-static time64_t pmu_read_time(void)
-{
-	struct adb_request req;
-	time64_t time;
-
-	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
-		return 0;
-	pmu_wait_complete(&req);
-
-	time = (u32)((req.reply[0] << 24) | (req.reply[1] << 16) |
-		     (req.reply[2] << 8) | req.reply[3]);
-
-	return time - RTC_OFFSET;
-}
-
-static void pmu_write_time(time64_t time)
-{
-	struct adb_request req;
-	u32 data = lower_32_bits(time + RTC_OFFSET);
-
-	if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
-			(data >> 24) & 0xFF, (data >> 16) & 0xFF,
-			(data >> 8) & 0xFF, data & 0xFF) < 0)
-		return;
-	pmu_wait_complete(&req);
-}
-
 static __u8 pmu_read_pram(int offset)
 {
 	struct adb_request req;
@@ -295,13 +239,17 @@ static time64_t via_read_time(void)
  * is basically any machine with Mac II-style ADB.
  */
 
-static void via_write_time(time64_t time)
+static void via_set_rtc_time(struct rtc_time *tm)
 {
 	union {
 		__u8 cdata[4];
 		__u32 idata;
 	} data;
 	__u8 temp;
+	time64_t time;
+
+	time = mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
+	                tm->tm_hour, tm->tm_min, tm->tm_sec);
 
 	/* Clear the write protect bit */
 
@@ -641,12 +589,12 @@ int mac_hwclk(int op, struct rtc_time *t)
 #ifdef CONFIG_ADB_CUDA
 		case MAC_ADB_EGRET:
 		case MAC_ADB_CUDA:
-			now = cuda_read_time();
+			now = cuda_get_time();
 			break;
 #endif
 #ifdef CONFIG_ADB_PMU
 		case MAC_ADB_PB2:
-			now = pmu_read_time();
+			now = pmu_get_time();
 			break;
 #endif
 		default:
@@ -665,24 +613,21 @@ int mac_hwclk(int op, struct rtc_time *t)
 		         __func__, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
 		         t->tm_hour, t->tm_min, t->tm_sec);
 
-		now = mktime64(t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
-			       t->tm_hour, t->tm_min, t->tm_sec);
-
 		switch (macintosh_config->adb_type) {
 		case MAC_ADB_IOP:
 		case MAC_ADB_II:
 		case MAC_ADB_PB1:
-			via_write_time(now);
+			via_set_rtc_time(t);
 			break;
 #ifdef CONFIG_ADB_CUDA
 		case MAC_ADB_EGRET:
 		case MAC_ADB_CUDA:
-			cuda_write_time(now);
+			cuda_set_rtc_time(t);
 			break;
 #endif
 #ifdef CONFIG_ADB_PMU
 		case MAC_ADB_PB2:
-			pmu_write_time(now);
+			pmu_set_rtc_time(t);
 			break;
 #endif
 		default:

arch/powerpc/platforms/powermac/time.c

@@ -44,13 +44,6 @@
 #define DBG(x...)
 #endif
 
-/*
- * Offset between Unix time (1970-based) and Mac time (1904-based). Cuda and PMU
- * times wrap in 2040. If we need to handle later times, the read_time functions
- * need to be changed to interpret wrapped times as post-2040.
- */
-#define RTC_OFFSET	2082844800
-
 /*
  * Calibrate the decrementer frequency with the VIA timer 1.
  */
@@ -90,98 +83,6 @@ long __init pmac_time_init(void)
 	return delta;
 }
 
-#ifdef CONFIG_ADB_CUDA
-static time64_t cuda_get_time(void)
-{
-	struct adb_request req;
-	time64_t now;
-
-	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
-		return 0;
-	while (!req.complete)
-		cuda_poll();
-	if (req.reply_len != 7)
-		printk(KERN_ERR "cuda_get_time: got %d byte reply\n",
-		       req.reply_len);
-	now = (u32)((req.reply[3] << 24) + (req.reply[4] << 16) +
-		    (req.reply[5] << 8) + req.reply[6]);
-	/* it's either after year 2040, or the RTC has gone backwards */
-	WARN_ON(now < RTC_OFFSET);
-
-	return now - RTC_OFFSET;
-}
-
-#define cuda_get_rtc_time(tm)	rtc_time64_to_tm(cuda_get_time(), (tm))
-
-static int cuda_set_rtc_time(struct rtc_time *tm)
-{
-	u32 nowtime;
-	struct adb_request req;
-
-	nowtime = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
-	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
-			 nowtime >> 24, nowtime >> 16, nowtime >> 8,
-			 nowtime) < 0)
-		return -ENXIO;
-	while (!req.complete)
-		cuda_poll();
-	if ((req.reply_len != 3) && (req.reply_len != 7))
-		printk(KERN_ERR "cuda_set_rtc_time: got %d byte reply\n",
-		       req.reply_len);
-	return 0;
-}
-
-#else
-#define cuda_get_time()		0
-#define cuda_get_rtc_time(tm)
-#define cuda_set_rtc_time(tm)	0
-#endif
-
-#ifdef CONFIG_ADB_PMU
-static time64_t pmu_get_time(void)
-{
-	struct adb_request req;
-	time64_t now;
-
-	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
-		return 0;
-	pmu_wait_complete(&req);
-	if (req.reply_len != 4)
-		printk(KERN_ERR "pmu_get_time: got %d byte reply from PMU\n",
-		       req.reply_len);
-	now = (u32)((req.reply[0] << 24) + (req.reply[1] << 16)	+
-		    (req.reply[2] << 8) + req.reply[3]);
-
-	/* it's either after year 2040, or the RTC has gone backwards */
-	WARN_ON(now < RTC_OFFSET);
-
-	return now - RTC_OFFSET;
-}
-
-#define pmu_get_rtc_time(tm)	rtc_time64_to_tm(pmu_get_time(), (tm))
-
-static int pmu_set_rtc_time(struct rtc_time *tm)
-{
-	u32 nowtime;
-	struct adb_request req;
-
-	nowtime = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
-	if (pmu_request(&req, NULL, 5, PMU_SET_RTC, nowtime >> 24,
-			nowtime >> 16, nowtime >> 8, nowtime) < 0)
-		return -ENXIO;
-	pmu_wait_complete(&req);
-	if (req.reply_len != 0)
-		printk(KERN_ERR "pmu_set_rtc_time: %d byte reply from PMU\n",
-		       req.reply_len);
-	return 0;
-}
-
-#else
-#define pmu_get_time()		0
-#define pmu_get_rtc_time(tm)
-#define pmu_set_rtc_time(tm)	0
-#endif
-
 #ifdef CONFIG_PMAC_SMU
 static time64_t smu_get_time(void)
 {
@@ -191,11 +92,6 @@ static time64_t smu_get_time(void)
 		return 0;
 	return rtc_tm_to_time64(&tm);
 }
-
-#else
-#define smu_get_time()			0
-#define smu_get_rtc_time(tm, spin)
-#define smu_set_rtc_time(tm, spin)	0
 #endif
 
 /* Can't be __init, it's called when suspending and resuming */
@@ -203,12 +99,18 @@ time64_t pmac_get_boot_time(void)
 {
 	/* Get the time from the RTC, used only at boot time */
 	switch (sys_ctrler) {
+#ifdef CONFIG_ADB_CUDA
 	case SYS_CTRLER_CUDA:
 		return cuda_get_time();
+#endif
+#ifdef CONFIG_ADB_PMU
 	case SYS_CTRLER_PMU:
 		return pmu_get_time();
+#endif
+#ifdef CONFIG_PMAC_SMU
 	case SYS_CTRLER_SMU:
 		return smu_get_time();
+#endif
 	default:
 		return 0;
 	}
@@ -218,15 +120,21 @@ void pmac_get_rtc_time(struct rtc_time *tm)
 {
 	/* Get the time from the RTC, used only at boot time */
 	switch (sys_ctrler) {
+#ifdef CONFIG_ADB_CUDA
 	case SYS_CTRLER_CUDA:
-		cuda_get_rtc_time(tm);
+		rtc_time64_to_tm(cuda_get_time(), tm);
 		break;
+#endif
+#ifdef CONFIG_ADB_PMU
 	case SYS_CTRLER_PMU:
-		pmu_get_rtc_time(tm);
+		rtc_time64_to_tm(pmu_get_time(), tm);
 		break;
+#endif
+#ifdef CONFIG_PMAC_SMU
 	case SYS_CTRLER_SMU:
 		smu_get_rtc_time(tm, 1);
 		break;
+#endif
 	default:
 		;
 	}
@@ -235,12 +143,18 @@ void pmac_get_rtc_time(struct rtc_time *tm)
 int pmac_set_rtc_time(struct rtc_time *tm)
 {
 	switch (sys_ctrler) {
+#ifdef CONFIG_ADB_CUDA
 	case SYS_CTRLER_CUDA:
 		return cuda_set_rtc_time(tm);
+#endif
+#ifdef CONFIG_ADB_PMU
 	case SYS_CTRLER_PMU:
 		return pmu_set_rtc_time(tm);
+#endif
+#ifdef CONFIG_PMAC_SMU
 	case SYS_CTRLER_SMU:
 		return smu_set_rtc_time(tm, 1);
+#endif
 	default:
 		return -ENODEV;
 	}

drivers/macintosh/via-cuda.c

@@ -766,3 +766,38 @@ cuda_input(unsigned char *buf, int nb)
 	               buf, nb, false);
     }
 }
+
+/* Offset between Unix time (1970-based) and Mac time (1904-based) */
+#define RTC_OFFSET	2082844800
+
+time64_t cuda_get_time(void)
+{
+	struct adb_request req;
+	u32 now;
+
+	if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0)
+		return 0;
+	while (!req.complete)
+		cuda_poll();
+	if (req.reply_len != 7)
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	now = (req.reply[3] << 24) + (req.reply[4] << 16) +
+	      (req.reply[5] << 8) + req.reply[6];
+	return (time64_t)now - RTC_OFFSET;
+}
+
+int cuda_set_rtc_time(struct rtc_time *tm)
+{
+	u32 now;
+	struct adb_request req;
+
+	now = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
+	if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME,
+	                 now >> 24, now >> 16, now >> 8, now) < 0)
+		return -ENXIO;
+	while (!req.complete)
+		cuda_poll();
+	if ((req.reply_len != 3) && (req.reply_len != 7))
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	return 0;
+}

drivers/macintosh/via-pmu.c

@@ -1737,6 +1737,39 @@ pmu_enable_irled(int on)
 	pmu_wait_complete(&req);
 }
 
+/* Offset between Unix time (1970-based) and Mac time (1904-based) */
+#define RTC_OFFSET	2082844800
+
+time64_t pmu_get_time(void)
+{
+	struct adb_request req;
+	u32 now;
+
+	if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0)
+		return 0;
+	pmu_wait_complete(&req);
+	if (req.reply_len != 4)
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	now = (req.reply[0] << 24) + (req.reply[1] << 16) +
+	      (req.reply[2] << 8) + req.reply[3];
+	return (time64_t)now - RTC_OFFSET;
+}
+
+int pmu_set_rtc_time(struct rtc_time *tm)
+{
+	u32 now;
+	struct adb_request req;
+
+	now = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET);
+	if (pmu_request(&req, NULL, 5, PMU_SET_RTC,
+	                now >> 24, now >> 16, now >> 8, now) < 0)
+		return -ENXIO;
+	pmu_wait_complete(&req);
+	if (req.reply_len != 0)
+		pr_err("%s: got %d byte reply\n", __func__, req.reply_len);
+	return 0;
+}
+
 void
 pmu_restart(void)
 {

include/linux/cuda.h

@@ -8,6 +8,7 @@
 #ifndef _LINUX_CUDA_H
 #define _LINUX_CUDA_H
 
+#include <linux/rtc.h>
 #include <uapi/linux/cuda.h>
 
 
@@ -16,4 +17,7 @@ extern int cuda_request(struct adb_request *req,
 			void (*done)(struct adb_request *), int nbytes, ...);
 extern void cuda_poll(void);
 
+extern time64_t cuda_get_time(void);
+extern int cuda_set_rtc_time(struct rtc_time *tm);
+
 #endif /* _LINUX_CUDA_H */

include/linux/pmu.h

@@ -9,6 +9,7 @@
 #ifndef _LINUX_PMU_H
 #define _LINUX_PMU_H
 
+#include <linux/rtc.h>
 #include <uapi/linux/pmu.h>
 
 
@@ -36,6 +37,9 @@ static inline void pmu_resume(void)
 
 extern void pmu_enable_irled(int on);
 
+extern time64_t pmu_get_time(void);
+extern int pmu_set_rtc_time(struct rtc_time *tm);
+
 extern void pmu_restart(void);
 extern void pmu_shutdown(void);
 extern void pmu_unlock(void);