diff options
Diffstat (limited to 'kernel/timer.c')
| -rw-r--r-- | kernel/timer.c | 95 |
1 files changed, 34 insertions, 61 deletions
diff --git a/kernel/timer.c b/kernel/timer.c index e5e26b4..2bf1592 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1,58 +1,29 @@ -/// PIT /// Timer stuff // CMOS - -/* - http://www.brokenthorn.com/Resources/OSDevPit.html - https://wiki.osdev.org/CMOS - - vcc/gnd - voltage/ground - - D0-D7 - data lines (data bus) - wr/rd - writing / reading (system control bus) - cs - ignore wr/rd or not (address bus) - a0-a1 (address bus) - - // the three 16bit down counters/timers/channels - clk 0-2 (in) - gate 0-2 (in) - out 0-2 (out) - - //typical - out1 -> pic interrupt on every tick (system timer) - out2 - was used for genearting dram memory refresh (Do not use) - out3 -> pc speaker - - gate pins : depend on mode of operation - we do have modes 0-5. - mode0: counts down to zero , triggers interrupt and waits - mode1: - mode2: rate generator (sys timer) - .... - */ - #define FOOLOS_MODULE_NAME "timer" - #include "timer.h" + #include "asm/x86.h" -#include "lib/logger/log.h" -// TODO: use mutex? do we need volatile at all!?? -// abstract atomic variable set,get,increment +//TODO: volatile? spinlock? static volatile uint64_t task_system_clock=0; static volatile uint64_t task_system_clock_start=0; +static volatile uint8_t interrupts_on = 0; -//called by interrupt +// interrupt handler (do NOT call yourself!) void timer_tick() { task_system_clock++; + interrupts_on=1; } // get value uint64_t timer_get_ticks() { - return task_system_clock; + uint64_t ret; +// x86_cli(); // do not disturb by timer_tick! + ret=task_system_clock; + // if(interrupts_on!=0)x86_sti(); // reenable (if clock was running already) + return ret; } -/// - uint64_t timer_get_ms() { @@ -68,24 +39,22 @@ uint64_t timer_get_uptime_ms() } // CMOS RTC - // read real time clock register -unsigned char get_rtc_reg(int reg) { +static unsigned char get_rtc_reg(int reg) { x86_outb(0x70, reg); //cmos at addr 0x70 return x86_inb(0x71); //cmos data at addr 0x71 } // check if cmos rtc update in progress -int get_rtc_update_flag() { +static int get_rtc_update_flag() { x86_outb(0x70, 0x0A); return (x86_inb(0x71) & 0x80); } // get real time clock rom cmos (seconds since jan) -uint64_t get_rtc_time() +static uint64_t get_rtc_time() { - int CURRENT_YEAR = 2018; // Change this each year! int century_register = 0x00; // Set by ACPI table parsing code if possible @@ -209,26 +178,13 @@ uint64_t get_rtc_time() ((year-1900 - 1) / 100) * 86400 + ((year-1900 + 299) / 400) * 86400; - log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"CMOS Hardware Clock: %u-%u-%u %u:%u:%u",day,month,year,hour,minute,second); - log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"CMOS Hardware Clock: %u seconds since Epoch",epoch_seconds); - return epoch_seconds; } -// PIT -// TODO: move to asm file -void timer_init() -{ - uint64_t epoch_time=get_rtc_time(); - - task_system_clock_start=epoch_time; - task_system_clock=epoch_time*25; - // config out timer on channel 0 : mode 2 (sys timer) - // http://en.wikipedia.org/wiki/Intel_8253#Control_Word_Register - // http://www.brokenthorn.com/Resources/OSDevPit.html - // int0 will be triggered ~25 times a second. - +// TODO: put in asm file! +static void timer_config() +{ __asm__("pusha"); __asm__("mov %0, %%dx"::"X" (1193180 / 25)); @@ -244,6 +200,23 @@ void timer_init() __asm__("popa"); - log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Configured PIT Channel 0 : Mode 2 : 1/25 s."); } +// PIT +uint64_t timer_init() +{ + uint64_t epoch_time=get_rtc_time(); + + task_system_clock_start=epoch_time; + task_system_clock=epoch_time*25; + + timer_config(); + + // config out timer on channel 0 : mode 2 (sys timer) + // http://en.wikipedia.org/wiki/Intel_8253#Control_Word_Register + // http://www.brokenthorn.com/Resources/OSDevPit.html + // int0 will be triggered ~25 times a second. + + //log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Configured PIT Channel 0 : Mode 2 : 1/25 s."); + return epoch_time; +} |