From: Kim, HeungJun <riverful.kim@samsung.com>
Date: Mon, 25 May 2009 08:40:42 +0000 (+0900)
Subject: [S5PC100] working udeay()
X-Git-Tag: s5pc110_universal_support~277
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f872c730642fd022bc1de1e689a35e2d73dd5019;p=kernel%2Fu-boot.git

[S5PC100] working udeay()
---

diff --git a/cpu/arm_cortexa8/s5pc100/interrupts.c b/cpu/arm_cortexa8/s5pc100/interrupts.c
index 1f93f10..a0175cc 100644
--- a/cpu/arm_cortexa8/s5pc100/interrupts.c
+++ b/cpu/arm_cortexa8/s5pc100/interrupts.c
@@ -45,8 +45,6 @@
 
 static ulong timer_load_val;
 
-#define PRESCALER	167
-
 static s5pc1xx_timers *s5pc1xx_get_base_timers(void)
 {
 	return (s5pc1xx_timers *)S5P_TIMER_BASE;
@@ -109,24 +107,9 @@ int interrupt_init(void)
  */
 unsigned long long get_ticks(void)
 {
-	ulong now = read_timer();
-
-	if (lastdec >= now) {
-		/* normal mode */
-		timestamp += lastdec - now;
-	} else {
-		/* we have an overflow ... */
-		timestamp += lastdec + timer_load_val - now;
-	}
-	lastdec = now;
-
-	return timestamp;
+	return get_timer(0);
 }
 
-/*
- * This function is derived from PowerPC code (timebase clock frequency).
- * On ARM it returns the number of timer ticks per second.
- */
 ulong get_tbclk(void)
 {
 	/* We overrun in 100s */
@@ -147,9 +130,19 @@ void reset_timer(void)
 
 ulong get_timer_masked(void)
 {
-	unsigned long long res = get_ticks();
-	do_div (res, (timer_load_val / (100 * CONFIG_SYS_HZ)));
-	return res;
+	ulong now = read_timer();
+
+	if (lastdec >= now) {
+		/* normal mode */
+		timestamp += lastdec - now;
+	}
+	else {
+		/* we have an overflow ... */
+		timestamp += lastdec + timer_load_val - now;
+	}
+	lastdec = now;
+
+	return timestamp;
 }
 
 ulong get_timer(ulong base)
@@ -159,17 +152,30 @@ ulong get_timer(ulong base)
 
 void set_timer(ulong t)
 {
-	timestamp = t * (timer_load_val / (100 * CONFIG_SYS_HZ));
+	timestamp = t;
 }
 
 void udelay(unsigned long usec)
 {
-	unsigned long long tmp;
-	ulong tmo;
+	ulong tmo, tmp;
 
-	tmo = (usec + 9) / 10;
-	tmp = get_ticks() + tmo;	/* get current timestamp */
+	if (usec >= 1000) {		/* if "big" number, spread normalization to seconds */
+		tmo = usec / 1000;	/* start to normalize for usec to ticks per sec */
+		tmo *= CFG_HZ;		/* find number of "ticks" to wait to achieve target */
+		tmo /= 1000;		/* finish normalize. */
+	}
+	else {				/* else small number, don't kill it prior to HZ multiply */
+		tmo = usec * CFG_HZ;
+		tmo /= (1000 * 1000);
+	}
+
+	tmp = get_timer(0);		/* get current timestamp */
+	if ((tmo + tmp + 1) < tmp)	/* if setting this fordward will roll time stamp */
+		reset_timer_masked();	/* reset "advancing" timestamp to 0, set lastdec value */
+	else
+		tmo += tmp;		/* else, set advancing stamp wake up time */
 
-	while (get_ticks() < tmp)/* loop till event */
+	while (get_timer_masked()<tmo)	/* loop till event */
 		 /*NOP*/;
 }
+
diff --git a/include/configs/s5pc100_tt.h b/include/configs/s5pc100_tt.h
index 1639ee8..2cb3dbe 100644
--- a/include/configs/s5pc100_tt.h
+++ b/include/configs/s5pc100_tt.h
@@ -202,6 +202,7 @@
 #define CONFIG_SYS_PTV			2       /* Divisor: 2^(PTV+1) => 8 */
 
 #define CONFIG_SYS_HZ			1000
+#define CFG_HZ					2085900		/* at PCLK 66.75MHz */
 
 /* valid baudrates */
 #define CONFIG_SYS_BAUDRATE_TABLE	{ 9600, 19200, 38400, 57600, 115200 }
diff --git a/include/s5pc1xx.h b/include/s5pc1xx.h
index 23cab1e..b0c621e 100644
--- a/include/s5pc1xx.h
+++ b/include/s5pc1xx.h
@@ -1665,6 +1665,8 @@ enum s5pc1xx_uarts_nr {
 	S5PC1XX_UART3,
 };
 
+ulong get_PCLK(void);
+
 #include "s5pc1x0.h"
 
 static inline s5pc1xx_uart *s5pc1xx_get_base_uart(enum s5pc1xx_uarts_nr nr)
@@ -1674,6 +1676,7 @@ static inline s5pc1xx_uart *s5pc1xx_get_base_uart(enum s5pc1xx_uarts_nr nr)
 #endif
 
 
+
 #endif /*__S5PC100_H__*/