X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86%2Ftime.c;h=22ea6181e45bbbcfbbbb6be36eca6b094eb28656;hb=7e5607004c3221d55c7992148b2f0d958cf28533;hp=4b2e0678453e1c88bd89f947422eff11c92077b7;hpb=33bcf4b3feb0e5e4548548bf3d2a50c52ffb6115;p=tpg%2Facess2.git diff --git a/Kernel/arch/x86/time.c b/Kernel/arch/x86/time.c index 4b2e0678..22ea6181 100644 --- a/Kernel/arch/x86/time.c +++ b/Kernel/arch/x86/time.c @@ -8,28 +8,60 @@ // === MACROS === #define TIMER_QUANTUM 100 // 2^(15-rate), 15: 1HZ, 5: 1024Hz, 2: 8192Hz -#define TIMER_RATE 12 // (Max: 15, Min: 2) - 15 = 1Hz, 13 = 4Hz, 12 = 8Hz, 11 = 16Hz 10 = 32Hz, 2 +// (Max: 15, Min: 2) - 15 = 1Hz, 13 = 4Hz, 12 = 8Hz, 11 = 16Hz 10 = 32Hz, 2 = 8192Hz +//#define TIMER_RATE 10 // 32 Hz +//#define TIMER_RATE 12 // 8 Hz +#define TIMER_RATE 14 // 2Hz +//#define TIMER_RATE 15 // 1HZ #define TIMER_FREQ (0x8000>>TIMER_RATE) //Hz #define MS_PER_TICK_WHOLE (1000/(TIMER_FREQ)) -#define MS_PER_TICK_FRACT ((Uint64)(1000*TIMER_FREQ-((Uint64)MS_PER_TICK_WHOLE)*0x80000000/TIMER_FREQ)) +#define MS_PER_TICK_FRACT ((0x80000000*(1000%TIMER_FREQ))/TIMER_FREQ) // === IMPORTS === -extern Sint64 giTimestamp; -extern Uint64 giTicks; -extern Uint64 giPartMiliseconds; +extern volatile Sint64 giTimestamp; +extern volatile Uint64 giTicks; +extern volatile Uint64 giPartMiliseconds; +extern void Timer_CallTimers(void); + +// === GLOBALS === +volatile Uint64 giTime_TSCAtLastTick = 0; +volatile Uint64 giTime_TSCPerTick = 0; // === PROTOTYPES === -void Time_Interrupt(); +//Sint64 now(void); + int Time_Setup(void); +void Time_Interrupt(int); +Uint64 Time_ReadTSC(void); // === CODE === /** - * \fn int Time_Setup() + * \fn Sint64 now() + * \brief Return the current timestamp + */ +Sint64 now(void) +{ + Uint64 tsc = Time_ReadTSC(); + tsc -= giTime_TSCAtLastTick; + tsc *= MS_PER_TICK_WHOLE; + if( giTime_TSCPerTick ) { + tsc /= giTime_TSCPerTick; + } + else + tsc = 0; + return giTimestamp + tsc; +} + +/** + * \fn int Time_Setup(void) * \brief Sets the system time from the Realtime-Clock */ -int Time_Setup() +int Time_Setup(void) { Uint8 val; + Log_Log("Timer", "RTC Timer firing at %iHz (%i divisor), %i.0x%08x", + TIMER_FREQ, TIMER_RATE, MS_PER_TICK_WHOLE, MS_PER_TICK_FRACT); + outb(0x70, inb(0x70)&0x7F); // Disable NMIs __asm__ __volatile__ ("cli"); // Disable normal interrupts @@ -47,20 +79,34 @@ int Time_Setup() outb(0x70, 0x0B); // Set the index again (a read will reset the index to register D) outb(0x71, val | 0x40); // Write the previous value or'd with 0x40. This turns on bit 6 of register D - __asm__ __volatile__ ("sti"); // Disable normal interrupts - outb(0x70, inb(0x70)|0x80); // Disable NMIs + __asm__ __volatile__ ("sti"); // Re-enable normal interrupts + outb(0x70, inb(0x70)|0x80); // Re-enable NMIs // Install IRQ Handler IRQ_AddHandler(8, Time_Interrupt); + + // Make sure the RTC actually fires + outb(0x70, 0x0C); // Select register C + inb(0x71); // Just throw away contents. + return 0; } /** - * \fn void Time_Interrupt() * \brief Called on the timekeeping IRQ + * \param irq IRQ number (unused) */ -void Time_Interrupt() +void Time_Interrupt(int irq) { + //Log("RTC Tick"); + Uint64 curTSC = Time_ReadTSC(); + + if( giTime_TSCAtLastTick ) + { + giTime_TSCPerTick = curTSC - giTime_TSCAtLastTick; + } + giTime_TSCAtLastTick = curTSC; + giTicks ++; giTimestamp += MS_PER_TICK_WHOLE; giPartMiliseconds += MS_PER_TICK_FRACT; @@ -78,9 +124,9 @@ void Time_Interrupt() #if 0 /** - * \fn void Time_TimerThread() + * \fn void Time_TimerThread(void) */ -void Time_TimerThread() +void Time_TimerThread(void) { Sint64 next; Threads_SetName("TIMER"); @@ -94,3 +140,10 @@ void Time_TimerThread() } } #endif + +Uint64 Time_ReadTSC(void) +{ + Uint32 a, d; + __asm__ __volatile__ ("rdtsc" : "=a" (a), "=d" (d)); + return ((Uint64)d << 32) | a; +}