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	 f01fd54d1b
			
		
	
	
		f01fd54d1b
		
	
	
	
	
		
			
			Instead of having a common entry point and looking at the PIC ISR to figure out which IRQ we're servicing, just make a separate entryway for each IRQ that pushes the IRQ number and jumps to a common routine. This fixes a weird issue where incoming network packets would sometimes cause the mouse to stop working. I didn't track it down further than realizing we were sometimes EOI'ing the wrong IRQ.
		
			
				
	
	
		
			80 lines
		
	
	
	
		
			1.8 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
	
		
			1.8 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| #include <Kernel/Arch/i386/CPU.h>
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| #include <Kernel/Arch/i386/PIC.h>
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| #include <Kernel/Arch/i386/PIT.h>
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| #include <Kernel/IO.h>
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| #include <Kernel/Scheduler.h>
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| 
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| #define IRQ_TIMER 0
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| 
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| extern "C" void timer_interrupt_entry();
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| extern "C" void timer_interrupt_handler(RegisterDump);
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| 
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| asm(
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|     ".globl timer_interrupt_entry \n"
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|     "timer_interrupt_entry: \n"
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|     "    pushl $0x0\n"
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|     "    pusha\n"
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|     "    pushl %ds\n"
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|     "    pushl %es\n"
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|     "    pushl %fs\n"
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|     "    pushl %gs\n"
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|     "    pushl %ss\n"
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|     "    mov $0x10, %ax\n"
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|     "    mov %ax, %ds\n"
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|     "    mov %ax, %es\n"
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|     "    cld\n"
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|     "    call timer_interrupt_handler\n"
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|     "    add $0x4, %esp\n"
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|     "    popl %gs\n"
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|     "    popl %fs\n"
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|     "    popl %es\n"
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|     "    popl %ds\n"
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|     "    popa\n"
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|     "    add $0x4, %esp\n"
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|     "    iret\n");
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| 
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| static u32 s_ticks_this_second;
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| static u32 s_seconds_since_boot;
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| 
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| void timer_interrupt_handler(RegisterDump regs)
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| {
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|     IRQHandlerScope scope(IRQ_TIMER);
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|     if (++s_ticks_this_second >= TICKS_PER_SECOND) {
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|         // FIXME: Synchronize with the RTC somehow to prevent drifting apart.
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|         ++s_seconds_since_boot;
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|         s_ticks_this_second = 0;
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|     }
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|     Scheduler::timer_tick(regs);
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| }
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| 
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| namespace PIT {
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| 
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| u32 ticks_this_second()
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| {
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|     return s_ticks_this_second;
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| }
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| 
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| u32 seconds_since_boot()
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| {
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|     return s_seconds_since_boot;
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| }
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| 
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| void initialize()
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| {
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|     u16 timer_reload;
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| 
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|     IO::out8(PIT_CTL, TIMER0_SELECT | WRITE_WORD | MODE_SQUARE_WAVE);
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| 
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|     timer_reload = (BASE_FREQUENCY / TICKS_PER_SECOND);
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| 
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|     kprintf("PIT: %u Hz, square wave (%x)\n", TICKS_PER_SECOND, timer_reload);
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| 
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|     IO::out8(TIMER0_CTL, LSB(timer_reload));
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|     IO::out8(TIMER0_CTL, MSB(timer_reload));
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| 
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|     register_interrupt_handler(IRQ_VECTOR_BASE + IRQ_TIMER, timer_interrupt_entry);
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| 
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|     PIC::enable(IRQ_TIMER);
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| }
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| 
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| }
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