[U-Boot] [PATCH v2] arm925t: Fix CONFIG_SYS_HZ to 1000
Dirk Behme
dirk.behme at googlemail.com
Wed Apr 22 16:51:59 CEST 2009
Ladislav Michl wrote:
> 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>
Acked-by: Dirk Behme <dirk.behme at googlemail.com>
> 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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