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Code Issues Releases Wiki Activity

ARCv2: clocksource: Introduce 64bit local RTC counter

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Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Vineet Gupta 2013-11-07 14:57:16 +05:30
parent b3210d141f
commit aa93e8ef98
3 changed files with 62 additions and 2 deletions
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5
arch/arc/Kconfig
View file

@ -372,6 +372,11 @@ config ARC_HAS_LL64
dest operands with 2 possible source operands.
default y
config ARC_HAS_RTC
bool "Local 64-bit r/o cycle counter"
default n
depends on !SMP
config ARC_NUMBER_OF_INTERRUPTS
int "Number of interrupts"
range 8 240

9
arch/arc/kernel/setup.c
View file

@ -200,9 +200,11 @@ static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
(unsigned int)(arc_get_core_freq() / 1000000),
(unsigned int)(arc_get_core_freq() / 10000) % 100);
n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s\nISA Extn\t: ",
n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
IS_AVAIL1(cpu->timers.t0, "Timer0 "),
IS_AVAIL1(cpu->timers.t1, "Timer1 "));
IS_AVAIL1(cpu->timers.t1, "Timer1 "),
IS_AVAIL2(cpu->timers.rtc, "64-bit RTC ",
CONFIG_ARC_HAS_RTC));
n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
@ -290,6 +292,9 @@ static void arc_chk_core_config(void)
if (!cpu->timers.t1)
panic("Timer1 is not present!\n");
if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->timers.rtc)
panic("RTC is not present\n");
#ifdef CONFIG_ARC_HAS_DCCM
/*
* DCCM can be arbit placed in hardware.

50
arch/arc/kernel/time.c
View file

@ -60,6 +60,54 @@
/********** Clock Source Device *********/
#ifdef CONFIG_ARC_HAS_RTC
#define AUX_RTC_CTRL 0x103
#define AUX_RTC_LOW 0x104
#define AUX_RTC_HIGH 0x105
int arc_counter_setup(void)
{
write_aux_reg(AUX_RTC_CTRL, 1);
/* Not usable in SMP */
return !IS_ENABLED(CONFIG_SMP);
}
static cycle_t arc_counter_read(struct clocksource *cs)
{
unsigned long status;
union {
#ifdef CONFIG_CPU_BIG_ENDIAN
struct { u32 high, low; };
#else
struct { u32 low, high; };
#endif
cycle_t full;
} stamp;
__asm__ __volatile(
"1: \n"
" lr %0, [AUX_RTC_LOW] \n"
" lr %1, [AUX_RTC_HIGH] \n"
" lr %2, [AUX_RTC_CTRL] \n"
" bbit0.nt %2, 31, 1b \n"
: "=r" (stamp.low), "=r" (stamp.high), "=r" (status));
return stamp.full;
}
static struct clocksource arc_counter = {
.name = "ARCv2 RTC",
.rating = 350,
.read = arc_counter_read,
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
#else /* !CONFIG_ARC_HAS_RTC */
/*
* set 32bit TIMER1 to keep counting monotonically and wraparound
*/
@ -86,6 +134,8 @@ static struct clocksource arc_counter = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
#endif
/********** Clock Event Device *********/
/*