[U-Boot] [PATCH v2] arm925t: Fix CONFIG_SYS_HZ to 1000
Ladislav Michl
ladis at linux-mips.org
Wed Apr 22 01:12:04 CEST 2009
Let CONFIG_SYS_HZ to have value of 1000 effectively fixing all users of
get_timer.
Changes since original version:
* Set PTV=2 (divisor 8) for boards using 12MHz timer clock source to
improve timer resolution.
Signed-off-by: Ladislav Michl <ladis at linux-mips.org>
diff --git a/cpu/arm925t/interrupts.c b/cpu/arm925t/interrupts.c
index e5c77f7..ec2a978 100644
--- a/cpu/arm925t/interrupts.c
+++ b/cpu/arm925t/interrupts.c
@@ -1,4 +1,7 @@
/*
+ * (C) Copyright 2009
+ * 2N Telekomunikace, <www.2n.cz>
+ *
* (C) Copyright 2003
* Texas Instruments, <www.ti.com>
*
@@ -37,7 +40,8 @@
#include <configs/omap1510.h>
#include <asm/io.h>
-#define TIMER_LOAD_VAL 0xffffffff
+#define TIMER_LOAD_VAL 0xffffffff
+#define TIMER_CLOCK (CONFIG_SYS_CLK_FREQ / (2 << CONFIG_SYS_PTV))
static uint32_t timestamp;
static uint32_t lastdec;
@@ -79,85 +83,41 @@ void set_timer (ulong t)
/* delay x useconds AND preserve advance timestamp value */
void udelay (unsigned long usec)
{
- ulong tmo, tmp;
-
- if (usec >= 1000) { /* if "big" number, spread normalization to seconds */
- tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
- tmo *= CONFIG_SYS_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 * CONFIG_SYS_HZ;
- tmo /= (1000*1000);
+ int32_t tmo = usec * (TIMER_CLOCK / 1000) / 1000;
+ uint32_t now, last = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
+
+ while (tmo > 0) {
+ now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
+ if (last < now) /* count down timer underflow */
+ tmo -= TIMER_LOAD_VAL - now + last;
+ else
+ tmo -= last - now;
+ last = now;
}
-
- 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_timer_masked () < tmo) /* loop till event */
- /*NOP*/;
}
void reset_timer_masked (void)
{
/* reset time */
- lastdec = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
+ lastdec = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM) /
+ (TIMER_CLOCK / CONFIG_SYS_HZ);
timestamp = 0; /* start "advancing" time stamp from 0 */
}
ulong get_timer_masked (void)
{
- uint32_t now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM);
-
- if (lastdec >= now) { /* normal mode (non roll) */
- /* normal mode */
- timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
- } else { /* we have overflow of the count down timer */
- /* nts = ts + ld + (TLV - now)
- * ts=old stamp, ld=time that passed before passing through -1
- * (TLV-now) amount of time after passing though -1
- * nts = new "advancing time stamp"...it could also roll and cause problems.
- */
- timestamp += lastdec + TIMER_LOAD_VAL - now;
- }
+ uint32_t now = __raw_readl(CONFIG_SYS_TIMERBASE + READ_TIM) /
+ (TIMER_CLOCK / CONFIG_SYS_HZ);
+ if (lastdec < now) /* count down timer underflow */
+ timestamp += TIMER_LOAD_VAL / (TIMER_CLOCK / CONFIG_SYS_HZ) -
+ now + lastdec;
+ else
+ timestamp += lastdec - now;
lastdec = now;
return timestamp;
}
-/* waits specified delay value and resets timestamp */
-void udelay_masked (unsigned long usec)
-{
-#ifdef CONFIG_INNOVATOROMAP1510
- #define LOOPS_PER_MSEC 60 /* tuned on omap1510 */
- volatile int i, time_remaining = LOOPS_PER_MSEC*usec;
- for (i=time_remaining; i>0; i--) { }
-#else
-
- ulong tmo;
- ulong endtime;
- signed long diff;
-
- if (usec >= 1000) { /* if "big" number, spread normalization to seconds */
- tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
- tmo *= CONFIG_SYS_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 * CONFIG_SYS_HZ;
- tmo /= (1000*1000);
- }
-
- endtime = get_timer_masked () + tmo;
-
- do {
- ulong now = get_timer_masked ();
- diff = endtime - now;
- } while (diff >= 0);
-#endif
-}
-
/*
* This function is derived from PowerPC code (read timebase as long long).
* On ARM it just returns the timer value.
diff --git a/include/configs/SX1.h b/include/configs/SX1.h
index caa6592..6149276 100644
--- a/include/configs/SX1.h
+++ b/include/configs/SX1.h
@@ -135,12 +135,12 @@
#define CONFIG_SYS_LOAD_ADDR 0x10000000 /* default load address */
-/* The 1510 has 3 timers, they can be driven by the RefClk (12Mhz) or by DPLL1.
+/* The 1510 has 3 timers, they can be driven by the RefClk (12MHz) or by DPLL1.
* This time is further subdivided by a local divisor.
*/
#define CONFIG_SYS_TIMERBASE OMAP1510_TIMER1_BASE /* use timer 1 */
-#define CONFIG_SYS_PTV 7 /* 2^(PTV+1), divide by 256 */
-#define CONFIG_SYS_HZ ((CONFIG_SYS_CLK_FREQ)/(2 << CONFIG_SYS_PTV))
+#define CONFIG_SYS_PTV 2 /* Divisor: 2^(PTV+1) => 8 */
+#define CONFIG_SYS_HZ 1000
/*-----------------------------------------------------------------------
* Stack sizes
diff --git a/include/configs/netstar.h b/include/configs/netstar.h
index 39560de..5cfee66 100644
--- a/include/configs/netstar.h
+++ b/include/configs/netstar.h
@@ -222,12 +222,12 @@
#define CONFIG_SYS_LOAD_ADDR PHYS_SDRAM_1 + 0x400000 /* default load address */
-/* The 1510 has 3 timers, they can be driven by the RefClk (12Mhz) or by DPLL1.
+/* The 1510 has 3 timers, they can be driven by the RefClk (12MHz) or by DPLL1.
* This time is further subdivided by a local divisor.
*/
#define CONFIG_SYS_TIMERBASE OMAP1510_TIMER1_BASE
-#define CONFIG_SYS_PTV 7 /* 2^(pvt+1), divide by 256 */
-#define CONFIG_SYS_HZ ((CONFIG_SYS_CLK_FREQ)/(2 << CONFIG_SYS_PTV))
+#define CONFIG_SYS_PTV 7
+#define CONFIG_SYS_HZ 1000
#define OMAP5910_DPLL_DIV 1
#define OMAP5910_DPLL_MUL ((CONFIG_SYS_CLK_FREQ * \
diff --git a/include/configs/omap1510inn.h b/include/configs/omap1510inn.h
index 6c1c5ec..8408209 100644
--- a/include/configs/omap1510inn.h
+++ b/include/configs/omap1510inn.h
@@ -132,12 +132,12 @@
#define CONFIG_SYS_LOAD_ADDR 0x10000000 /* default load address */
-/* The 1510 has 3 timers, they can be driven by the RefClk (12Mhz) or by DPLL1.
+/* The 1510 has 3 timers, they can be driven by the RefClk (12MHz) or by DPLL1.
* This time is further subdivided by a local divisor.
*/
#define CONFIG_SYS_TIMERBASE OMAP1510_TIMER1_BASE /* use timer 1 */
-#define CONFIG_SYS_PTV 7 /* 2^(PTV+1), divide by 256 */
-#define CONFIG_SYS_HZ ((CONFIG_SYS_CLK_FREQ)/(2 << CONFIG_SYS_PTV))
+#define CONFIG_SYS_PTV 2 /* Divisor: 2^(PTV+1) => 8 */
+#define CONFIG_SYS_HZ 1000
/*-----------------------------------------------------------------------
* Stack sizes
diff --git a/include/configs/voiceblue.h b/include/configs/voiceblue.h
index 3f97843..aa8efaa 100644
--- a/include/configs/voiceblue.h
+++ b/include/configs/voiceblue.h
@@ -210,12 +210,12 @@
#define CONFIG_SYS_MEMTEST_START PHYS_SDRAM_1
#define CONFIG_SYS_MEMTEST_END PHYS_SDRAM_1 + PHYS_SDRAM_1_SIZE - PHYS_SDRAM_1_RESERVED
-/* The 1510 has 3 timers, they can be driven by the RefClk (12Mhz) or by DPLL1.
+/* The 1510 has 3 timers, they can be driven by the RefClk (12MHz) or by DPLL1.
* This time is further subdivided by a local divisor.
*/
#define CONFIG_SYS_TIMERBASE OMAP1510_TIMER1_BASE
#define CONFIG_SYS_PTV 7 /* 2^(PTV+1), divide by 256 */
-#define CONFIG_SYS_HZ ((CONFIG_SYS_CLK_FREQ)/(2 << CONFIG_SYS_PTV))
+#define CONFIG_SYS_HZ 1000
#define OMAP5910_DPLL_DIV 1
#define OMAP5910_DPLL_MUL ((CONFIG_SYS_CLK_FREQ * \
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