diff options
Diffstat (limited to 'i386/i386at/ioapic.c')
| -rw-r--r-- | i386/i386at/ioapic.c | 81 |
1 files changed, 46 insertions, 35 deletions
diff --git a/i386/i386at/ioapic.c b/i386/i386at/ioapic.c index d2ea84ad..c6da35e1 100644 --- a/i386/i386at/ioapic.c +++ b/i386/i386at/ioapic.c @@ -28,11 +28,13 @@ #include <i386/pio.h> #include <i386/pit.h> #include <i386/pic.h> /* only for macros */ +#include <i386/smp.h> #include <mach/machine.h> #include <kern/printf.h> +#include <kern/timer.h> static int has_irq_specific_eoi = 1; /* FIXME: Assume all machines have this */ -int duplicate_pin; +int timer_pin; uint32_t lapic_timer_val = 0; uint32_t calibrated_ticks = 0; @@ -43,7 +45,7 @@ int iunit[NINTR] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23}; interrupt_handler_fn ivect[NINTR] = { - /* 00 */ intnull, /* install timer later */ + /* 00 */ (interrupt_handler_fn)hardclock, /* 01 */ kdintr, /* kdintr, ... */ /* 02 */ intnull, /* 03 */ intnull, /* lnpoll, comintr, ... */ @@ -150,32 +152,58 @@ ioapic_toggle_entry(int apic, int pin, int mask) ioapic_write(apic, APIC_IO_REDIR_LOW(pin), entry.lo); } +static void timer_expiry_callback(void *arg) +{ + volatile int *done = arg; + *done = 1; +} + static uint32_t -pit_measure_10x_apic_hz(void) +timer_measure_10x_apic_hz(void) { - volatile int i; + volatile int done = 0; uint32_t start = 0xffffffff; + timer_elt_data_t tmp_timer; + tmp_timer.fcn = timer_expiry_callback; + tmp_timer.param = (void *)&done; - /* Prepare accurate delay for 1/hz seconds */ - pit_prepare_sleep(hz); + printf("timer calibration..."); /* Set APIC timer */ lapic->init_count.r = start; - /* zZz */ - for (i = 0; i < 10; i++) - pit_sleep(); + /* Delay for 10 * 1/hz seconds */ + set_timeout(&tmp_timer, hz / 10); + do { + cpu_pause(); + } while (!done); /* Stop APIC timer */ lapic->lvt_timer.r |= LAPIC_DISABLE; + printf(" done\n"); + return start - lapic->cur_count.r; } -void lapic_update_timer(void) +void +calibrate_lapic_timer(void) { - /* Timer decrements until zero and then calls this on every interrupt */ - lapic_timer_val += calibrated_ticks; + spl_t s; + + /* Set one-shot timer */ + lapic->divider_config.r = LAPIC_TIMER_DIVIDE_2; + lapic->lvt_timer.r = IOAPIC_INT_BASE; + + /* Measure number of APIC timer ticks in 10x 1/hz seconds + * but calibrate the timer to expire at rate of hz + * divide by 10 because we waited 10 times longer than we needed. */ + if (!calibrated_ticks) { + s = splhigh(); + spl0(); + calibrated_ticks = timer_measure_10x_apic_hz() / 10; + splx(s); + } } void @@ -306,16 +334,14 @@ ioapic_configure(void) /* Save timer info */ timer_gsi = gsi; } else { - /* Disable duplicated timer gsi */ + /* Remap timer irq */ if (gsi == timer_gsi) { - duplicate_pin = pin; - /* Remap this interrupt pin to GSI base - * so we don't duplicate vectors */ + timer_pin = pin; + /* Remap GSI base to timer pin so ivect[0] is the timer */ entry.both.vector = IOAPIC_INT_BASE; - ioapic_write_entry(apic, duplicate_pin, entry.both); - /* Mask the ioapic pin with deduplicated vector as - * we will never use it, since timer is on another gsi */ - mask_irq(duplicate_pin); + ioapic_write_entry(apic, timer_pin, entry.both); + /* Mask the duplicate pin 0 as we will be using timer_pin */ + mask_irq(0); } } } @@ -337,20 +363,5 @@ ioapic_configure(void) /* Start the IO APIC receiving interrupts */ lapic_enable(); - /* Set one-shot timer */ - lapic->divider_config.r = LAPIC_TIMER_DIVIDE_2; - lapic->lvt_timer.r = IOAPIC_INT_BASE; - - /* Measure number of APIC timer ticks in 10x 1/hz seconds - * but calibrate the timer to expire at rate of hz - * divide by 10 because we waited 10 times longer than we needed */ - calibrated_ticks = pit_measure_10x_apic_hz() / 10; - - /* Set up counter later */ - lapic->lvt_timer.r = LAPIC_DISABLE; - - /* Install clock interrupt handler on pin 0 */ - ivect[0] = (interrupt_handler_fn)hardclock; - printf("IOAPIC 0 configured\n"); } |