116 lines
2.4 KiB
C
116 lines
2.4 KiB
C
#include <linux/types.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/mc146818rtc.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/timex.h>
|
|
|
|
#include <asm/hardirq.h>
|
|
#include <asm/div64.h>
|
|
#include <asm/cpu.h>
|
|
#include <asm/time.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/mc146818-time.h>
|
|
#include <asm/msc01_ic.h>
|
|
|
|
#include <asm/mips-boards/generic.h>
|
|
#include <asm/mips-boards/prom.h>
|
|
#include <asm/mips-boards/simint.h>
|
|
|
|
|
|
unsigned long cpu_khz;
|
|
|
|
/*
|
|
* Estimate CPU frequency. Sets mips_hpt_frequency as a side-effect
|
|
*/
|
|
static unsigned int __init estimate_cpu_frequency(void)
|
|
{
|
|
unsigned int prid = read_c0_prid() & 0xffff00;
|
|
unsigned int count;
|
|
|
|
#if 1
|
|
/*
|
|
* hardwire the board frequency to 12MHz.
|
|
*/
|
|
|
|
if ((prid == (PRID_COMP_MIPS | PRID_IMP_20KC)) ||
|
|
(prid == (PRID_COMP_MIPS | PRID_IMP_25KF)))
|
|
count = 12000000;
|
|
else
|
|
count = 6000000;
|
|
#else
|
|
unsigned int flags;
|
|
|
|
local_irq_save(flags);
|
|
|
|
/* Start counter exactly on falling edge of update flag */
|
|
while (CMOS_READ(RTC_REG_A) & RTC_UIP);
|
|
while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
|
|
|
|
/* Start r4k counter. */
|
|
write_c0_count(0);
|
|
|
|
/* Read counter exactly on falling edge of update flag */
|
|
while (CMOS_READ(RTC_REG_A) & RTC_UIP);
|
|
while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
|
|
|
|
count = read_c0_count();
|
|
|
|
/* restore interrupts */
|
|
local_irq_restore(flags);
|
|
#endif
|
|
|
|
mips_hpt_frequency = count;
|
|
|
|
if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
|
|
(prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
|
|
count *= 2;
|
|
|
|
count += 5000; /* round */
|
|
count -= count%10000;
|
|
|
|
return count;
|
|
}
|
|
|
|
static int mips_cpu_timer_irq;
|
|
|
|
static void mips_timer_dispatch(void)
|
|
{
|
|
do_IRQ(mips_cpu_timer_irq);
|
|
}
|
|
|
|
|
|
unsigned __cpuinit get_c0_compare_int(void)
|
|
{
|
|
#ifdef MSC01E_INT_BASE
|
|
if (cpu_has_veic) {
|
|
set_vi_handler(MSC01E_INT_CPUCTR, mips_timer_dispatch);
|
|
mips_cpu_timer_irq = MSC01E_INT_BASE + MSC01E_INT_CPUCTR;
|
|
} else {
|
|
#endif
|
|
if (cpu_has_vint)
|
|
set_vi_handler(cp0_compare_irq, mips_timer_dispatch);
|
|
mips_cpu_timer_irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
|
|
}
|
|
|
|
return mips_cpu_timer_irq;
|
|
}
|
|
|
|
void __init plat_time_init(void)
|
|
{
|
|
unsigned int est_freq;
|
|
|
|
/* Set Data mode - binary. */
|
|
CMOS_WRITE(CMOS_READ(RTC_CONTROL) | RTC_DM_BINARY, RTC_CONTROL);
|
|
|
|
est_freq = estimate_cpu_frequency();
|
|
|
|
printk(KERN_INFO "CPU frequency %d.%02d MHz\n", est_freq / 1000000,
|
|
(est_freq % 1000000) * 100 / 1000000);
|
|
|
|
cpu_khz = est_freq / 1000;
|
|
}
|