diff options
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/arch/amd64/amd64/lapic.c | 109 | ||||
| -rw-r--r-- | sys/arch/amd64/amd64/lapic_intr.S | 9 | ||||
| -rw-r--r-- | sys/include/arch/amd64/cpu.h | 1 |
3 files changed, 119 insertions, 0 deletions
diff --git a/sys/arch/amd64/amd64/lapic.c b/sys/arch/amd64/amd64/lapic.c index f61715d..823e830 100644 --- a/sys/arch/amd64/amd64/lapic.c +++ b/sys/arch/amd64/amd64/lapic.c @@ -32,11 +32,15 @@ #include <sys/panic.h> #include <sys/mmio.h> #include <sys/syslog.h> +#include <dev/timer.h> +#include <machine/intr.h> +#include <machine/isa/i8254.h> #include <machine/lapicvar.h> #include <machine/lapic.h> #include <machine/cpuid.h> #include <machine/cpu.h> #include <machine/msr.h> +#include <machine/idt.h> #define pr_trace(fmt, ...) kprintf("lapic: " fmt, ##__VA_ARGS__) @@ -52,8 +56,12 @@ } \ } while (0); +static struct timer lapic_timer; +static uint8_t lapic_timer_vec = 0; uintptr_t g_lapic_base = 0; +void lapic_tmr_isr(void); + /* * Returns true if LAPIC is supported. * @@ -124,6 +132,62 @@ lapic_writel(uint32_t reg, uint64_t val) } /* + * Starts the Local APIC countdown timer... + * + * @mask: True to mask timer. + * @mode: Timer mode. + * @count: Count to start at. + */ +static inline void +lapic_timer_start(bool mask, uint8_t mode, uint32_t count) +{ + uint32_t tmp; + + tmp = (mode << 17) | (mask << 16) | lapic_timer_vec; + lapic_writel(LAPIC_LVT_TMR, tmp); + lapic_writel(LAPIC_DCR, 0); + lapic_writel(LAPIC_INIT_CNT, count); +} + +/* + * Start Local APIC timer oneshot with number + * of ticks to count down from. + * + * @mask: If `true', timer will be masked, `count' should be 0. + * @count: Number of ticks. + */ +static void +lapic_timer_oneshot(bool mask, uint32_t count) +{ + lapic_timer_start(mask, LVT_TMR_ONESHOT, count); +} + +/* + * Start Local APIC timer oneshot in microseconds. + * + * @us: Microseconds. + */ +static void +lapic_timer_oneshot_us(size_t usec) +{ + uint64_t ticks; + struct cpu_info *ci = this_cpu(); + + ticks = usec * (ci->lapic_tmr_freq / 1000000); + lapic_timer_oneshot(false, ticks); +} + +/* + * Stops the Local APIC timer + */ +static void +lapic_timer_stop(void) +{ + lapic_writel(LAPIC_LVT_TMR, LAPIC_LVT_MASK); + lapic_writel(LAPIC_INIT_CNT, 0); +} + +/* * Set bits within a LAPIC register * without overwriting the whole thing. * @@ -187,10 +251,37 @@ lapic_read_id(const struct cpu_info *ci) } } +/* + * Init the Local APIC timer and return + * the frequency. + */ +static size_t +lapic_timer_init(void) +{ + uint16_t ticks_start, ticks_end; + size_t ticks_total, freq; + const uint16_t MAX_SAMPLES = 0xFFFF; + + lapic_timer_stop(); + i8254_set_reload(MAX_SAMPLES); + ticks_start = i8254_get_count(); + + lapic_writel(LAPIC_INIT_CNT, MAX_SAMPLES); + while (lapic_readl(LAPIC_CUR_CNT) != 0); + + ticks_end = i8254_get_count(); + ticks_total = ticks_start - ticks_end; + + freq = (MAX_SAMPLES / ticks_total) * I8254_DIVIDEND; + lapic_timer_stop(); + return freq; +} + void lapic_init(void) { struct cpu_info *ci = this_cpu(); + tmrr_status_t tmr_status; /* * Hyra currently depends on the existance @@ -200,6 +291,12 @@ lapic_init(void) panic("This machine does not support LAPIC!\n"); } + /* Allocate a vector if needed */ + if (lapic_timer_vec == 0) { + lapic_timer_vec = intr_alloc_vector(); + idt_set_desc(lapic_timer_vec, IDT_INT_GATE, ISR(lapic_tmr_isr), 0); + } + /* Ensure the LAPIC base is valid */ if (g_lapic_base == 0) { panic("Invalid LAPIC base\n"); @@ -209,6 +306,18 @@ lapic_init(void) lapic_enable(ci); ci->apicid = lapic_read_id(ci); + ci->lapic_tmr_freq = lapic_timer_init(); bsp_trace("BSP LAPIC enabled in %s mode (id=%d)\n", ci->has_x2apic ? "x2APIC" : "xAPIC", ci->apicid); + + /* Try to register the timer */ + lapic_timer.name = "LAPIC_INTEGRATED_TIMER"; + lapic_timer.stop = lapic_timer_stop; + lapic_timer.oneshot_us = lapic_timer_oneshot_us; + tmr_status = register_timer(TIMER_SCHED, &lapic_timer); + + /* This should not happen but handle it just in case */ + if (__unlikely(tmr_status != TMRR_SUCCESS)) { + panic("Failed to register %s\n", lapic_timer.name); + } } diff --git a/sys/arch/amd64/amd64/lapic_intr.S b/sys/arch/amd64/amd64/lapic_intr.S new file mode 100644 index 0000000..295de2d --- /dev/null +++ b/sys/arch/amd64/amd64/lapic_intr.S @@ -0,0 +1,9 @@ +#include <machine/frameasm.h> + + .text + .globl lapic_tmr_isr +lapic_tmr_isr: + push_trapframe $0 + mov %rsp, %rdi + pop_trapframe + iretq diff --git a/sys/include/arch/amd64/cpu.h b/sys/include/arch/amd64/cpu.h index 4e5baf1..92d2356 100644 --- a/sys/include/arch/amd64/cpu.h +++ b/sys/include/arch/amd64/cpu.h @@ -36,6 +36,7 @@ struct cpu_info { uint32_t apicid; uint8_t has_x2apic : 1; + size_t lapic_tmr_freq; }; void cpu_startup(void); |