The timer has been rewrote with a precision at ~0,18%
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD plagnioj@jcrosoft.com --- cpu/arm926ejs/at91/timer.c | 82 +++++++++++++++++++++------------------ include/configs/afeb9260.h | 2 +- include/configs/at91cap9adk.h | 2 +- include/configs/at91sam9260ek.h | 2 +- include/configs/at91sam9261ek.h | 2 +- include/configs/at91sam9263ek.h | 2 +- include/configs/at91sam9rlek.h | 2 +- include/configs/pm9263.h | 2 +- 8 files changed, 51 insertions(+), 45 deletions(-)
diff --git a/cpu/arm926ejs/at91/timer.c b/cpu/arm926ejs/at91/timer.c index fec545b..c84cb5e 100644 --- a/cpu/arm926ejs/at91/timer.c +++ b/cpu/arm926ejs/at91/timer.c @@ -27,7 +27,9 @@ #include <asm/arch/at91_pit.h> #include <asm/arch/at91_pmc.h> #include <asm/arch/at91_rstc.h> +#include <asm/arch/clk.h> #include <asm/arch/io.h> +#include <div64.h>
/* * We're using the AT91CAP9/SAM9 PITC in 32 bit mode, by @@ -36,11 +38,26 @@ #define TIMER_LOAD_VAL 0xfffff #define READ_RESET_TIMER at91_sys_read(AT91_PIT_PIVR) #define READ_TIMER at91_sys_read(AT91_PIT_PIIR) -#define TIMER_FREQ (AT91C_MASTER_CLOCK << 4) -#define TICKS_TO_USEC(ticks) ((ticks) / 6)
-ulong get_timer_masked(void); -ulong resettime; +static ulong timestamp; +static ulong lastinc; +static ulong timer_freq; + +static inline unsigned long long tick_to_time(unsigned long long tick) +{ + tick *= CONFIG_SYS_HZ; + do_div(tick, timer_freq); + + return tick; +} + +static inline unsigned long long usec_to_tick(unsigned long long usec) +{ + usec *= timer_freq; + do_div(usec, 1000000); + + return usec; +}
/* nothing really to do with interrupts, just starts up a counter. */ int timer_init(void) @@ -56,41 +73,49 @@ int timer_init(void)
reset_timer_masked();
+ timer_freq = get_mck_clk_rate() >> 4; + return 0; }
/* * timer without interrupts */ - -static inline ulong get_timer_raw(void) +unsigned long long get_ticks(void) { ulong now = READ_TIMER;
- if (now >= resettime) - return now - resettime; - else - return 0xFFFFFFFFUL - (resettime - now) ; + if (now >= lastinc) /* normal mode (non roll) */ + /* move stamp forward with absolut diff ticks */ + timestamp += (now - lastinc); + else /* we have rollover of incrementer */ + timestamp += (0xFFFFFFFF - lastinc) + now; + lastinc = now; + return timestamp; }
void reset_timer_masked(void) { - resettime = READ_TIMER; + /* reset time */ + lastinc = READ_TIMER; /* capture current incrementer value time */ + timestamp = 0; /* start "advancing" time stamp from 0 */ }
ulong get_timer_masked(void) { - return TICKS_TO_USEC(get_timer_raw()); - + return tick_to_time(get_ticks()); }
-void udelay_masked(unsigned long usec) +void udelay(unsigned long usec) { - ulong tmp; + unsigned long long tmp; + ulong tmo;
- tmp = get_timer(0); - while (get_timer(tmp) < usec) /* our timer works in usecs */ - ; /* NOP */ + tmo = usec_to_tick(usec); + tmp = get_ticks() + tmo; /* get current timestamp */ + + while (get_ticks() < tmp) /* loop till event */ + /*NOP*/; }
void reset_timer(void) @@ -100,26 +125,7 @@ void reset_timer(void)
ulong get_timer(ulong base) { - ulong now = get_timer_masked(); - - if (now >= base) - return now - base; - else - return TICKS_TO_USEC(0xFFFFFFFFUL) - (base - now) ; -} - -void udelay(unsigned long usec) -{ - udelay_masked(usec); -} - -/* - * This function is derived from PowerPC code (read timebase as long long). - * On ARM it just returns the timer value. - */ -unsigned long long get_ticks(void) -{ - return get_timer(0); + return get_timer_masked () - base; }
/* diff --git a/include/configs/afeb9260.h b/include/configs/afeb9260.h index ffa7fad..5679b3f 100644 --- a/include/configs/afeb9260.h +++ b/include/configs/afeb9260.h @@ -28,7 +28,7 @@
/* ARM asynchronous clock */ #define AT91_MAIN_CLOCK 18429952 /* from 18.432 MHz crystal */ -#define CONFIG_SYS_HZ 1000000 /* 1us resolution */ +#define CONFIG_SYS_HZ 1000
#define CONFIG_AT91SAM9260 1 /* It's an Atmel AT91SAM9260 SoC*/ #define CONFIG_AFEB9260 1 /* on an AFEB9260 Board */ diff --git a/include/configs/at91cap9adk.h b/include/configs/at91cap9adk.h index 51f9051..b14cd73 100644 --- a/include/configs/at91cap9adk.h +++ b/include/configs/at91cap9adk.h @@ -30,7 +30,7 @@ /* ARM asynchronous clock */ #define AT91_CPU_NAME "AT91CAP9" #define AT91_MAIN_CLOCK 12000000 /* 12 MHz crystal */ -#define CONFIG_SYS_HZ 1000000 /* 1us resolution */ +#define CONFIG_SYS_HZ 1000
#define CONFIG_ARM926EJS 1 /* This is an ARM926EJS Core */ #define CONFIG_AT91CAP9 1 /* It's an Atmel AT91CAP9 SoC */ diff --git a/include/configs/at91sam9260ek.h b/include/configs/at91sam9260ek.h index 558f648..70ceabf 100644 --- a/include/configs/at91sam9260ek.h +++ b/include/configs/at91sam9260ek.h @@ -29,7 +29,7 @@
/* ARM asynchronous clock */ #define AT91_MAIN_CLOCK 18432000 /* 18.432 MHz crystal */ -#define CONFIG_SYS_HZ 1000000 /* 1us resolution */ +#define CONFIG_SYS_HZ 1000
#define CONFIG_ARM926EJS 1 /* This is an ARM926EJS Core */
diff --git a/include/configs/at91sam9261ek.h b/include/configs/at91sam9261ek.h index 5f7bef8..7766513 100644 --- a/include/configs/at91sam9261ek.h +++ b/include/configs/at91sam9261ek.h @@ -30,7 +30,7 @@ /* ARM asynchronous clock */ #define AT91_CPU_NAME "AT91SAM9261" #define AT91_MAIN_CLOCK 18432000 /* 18.432 MHz crystal */ -#define CONFIG_SYS_HZ 1000000 /* 1us resolution */ +#define CONFIG_SYS_HZ 1000
#define CONFIG_ARM926EJS 1 /* This is an ARM926EJS Core */ #define CONFIG_AT91SAM9261 1 /* It's an Atmel AT91SAM9261 SoC*/ diff --git a/include/configs/at91sam9263ek.h b/include/configs/at91sam9263ek.h index 506295b..9119e53 100644 --- a/include/configs/at91sam9263ek.h +++ b/include/configs/at91sam9263ek.h @@ -30,7 +30,7 @@ /* ARM asynchronous clock */ #define AT91_CPU_NAME "AT91SAM9263" #define AT91_MAIN_CLOCK 16367660 /* 16.367 MHz crystal */ -#define CONFIG_SYS_HZ 1000000 /* 1us resolution */ +#define CONFIG_SYS_HZ 1000
#define CONFIG_ARM926EJS 1 /* This is an ARM926EJS Core */ #define CONFIG_AT91SAM9263 1 /* It's an Atmel AT91SAM9263 SoC*/ diff --git a/include/configs/at91sam9rlek.h b/include/configs/at91sam9rlek.h index 8a35303..1aaf9fb 100644 --- a/include/configs/at91sam9rlek.h +++ b/include/configs/at91sam9rlek.h @@ -30,7 +30,7 @@ /* ARM asynchronous clock */ #define AT91_CPU_NAME "AT91SAM9RL" #define AT91_MAIN_CLOCK 12000000 /* 12 MHz crystal */ -#define CONFIG_SYS_HZ 1000000 /* 1us resolution */ +#define CONFIG_SYS_HZ 1000
#define CONFIG_ARM926EJS 1 /* This is an ARM926EJS Core */ #define CONFIG_AT91SAM9RL 1 /* It's an Atmel AT91SAM9RL SoC*/ diff --git a/include/configs/pm9263.h b/include/configs/pm9263.h index 33e320c..5ab8f3f 100644 --- a/include/configs/pm9263.h +++ b/include/configs/pm9263.h @@ -38,7 +38,7 @@ #define MAIN_PLL_DIV 2 /* 2 or 4 */ #define AT91_MAIN_CLOCK 18432000
-#define CONFIG_SYS_HZ 1000000 +#define CONFIG_SYS_HZ 1000
#define CONFIG_ARM926EJS 1 /* This is an ARM926EJS Core */ #define CONFIG_AT91SAM9263 1 /* It's an Atmel AT91SAM9263 SoC*/