From 46bb1d3157f9ad575c83a4bfa1e32b0d21bc8546 Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Sat, 14 Sep 2019 01:42:29 -0700 Subject: 5650 - support a second OS: soso https://github.com/ozkl/soso + Much smaller than Linux; builds instantly + Supports graphics - No network support - Doesn't work on a cloud server (yet?) --- kernel.soso/descriptortables.c | 211 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 211 insertions(+) create mode 100644 kernel.soso/descriptortables.c (limited to 'kernel.soso/descriptortables.c') diff --git a/kernel.soso/descriptortables.c b/kernel.soso/descriptortables.c new file mode 100644 index 00000000..258e33c6 --- /dev/null +++ b/kernel.soso/descriptortables.c @@ -0,0 +1,211 @@ +#include "screen.h" +#include "common.h" +#include "descriptortables.h" +#include "isr.h" +#include "process.h" + +extern void flushGdt(uint32); +extern void flushIdt(uint32); +extern void flushTss(); + + +static void initializeGdt(); +static void initializeIdt(); +static void setGdtEntry(int32 num, uint32 base, uint32 limit, uint8 access, uint8 gran); +static void setIdtEntry(uint8 num, uint32 base, uint16 sel, uint8 flags); + +GdtEntry gGdtEntries[6]; +GdtPointer gGdtPointer; +IdtEntry gIdtEntries[256]; +IdtPointer gIdtPointer; +Tss gTss; + +extern IsrFunction gInterruptHandlers[]; + +static void handleDoubleFault(Registers *regs); +static void handleGeneralProtectionFault(Registers *regs); + +void initializeDescriptorTables() +{ + initializeGdt(); + + initializeIdt(); + + memset((uint8*)&gInterruptHandlers, 0, sizeof(IsrFunction)*256); + + registerInterruptHandler(8, handleDoubleFault); + registerInterruptHandler(13, handleGeneralProtectionFault); +} + +static void initializeGdt() +{ + gGdtPointer.limit = (sizeof(GdtEntry) * 6) - 1; + gGdtPointer.base = (uint32)&gGdtEntries; + + setGdtEntry(0, 0, 0, 0, 0); // 0x00 Null segment + setGdtEntry(1, 0, 0xFFFFFFFF, 0x9A, 0xCF); // 0x08 Code segment + setGdtEntry(2, 0, 0xFFFFFFFF, 0x92, 0xCF); // 0x10 Data segment + setGdtEntry(3, 0, 0xFFFFFFFF, 0xFA, 0xCF); // 0x18 User mode code segment + setGdtEntry(4, 0, 0xFFFFFFFF, 0xF2, 0xCF); // 0x20 User mode data segment + + //TSS + memset((uint8*)&gTss, 0, sizeof(gTss)); + gTss.debug_flag = 0x00; + gTss.io_map = 0x00; + gTss.esp0 = 0;//0x1FFF0; + gTss.ss0 = 0x10;//0x18; + + gTss.cs = 0x0B; //from ring 3 - 0x08 | 3 = 0x0B + gTss.ss = gTss.ds = gTss.es = gTss.fs = gTss.gs = 0x13; //from ring 3 = 0x10 | 3 = 0x13 + uint32 tss_base = (uint32) &gTss; + uint32 tss_limit = tss_base + sizeof(gTss); + setGdtEntry(5, tss_base, tss_limit, 0xE9, 0x00); + + flushGdt((uint32)&gGdtPointer); + flushTss(); +} + +// Set the value of one GDT entry. +static void setGdtEntry(int32 num, uint32 base, uint32 limit, uint8 access, uint8 gran) +{ + gGdtEntries[num].base_low = (base & 0xFFFF); + gGdtEntries[num].base_middle = (base >> 16) & 0xFF; + gGdtEntries[num].base_high = (base >> 24) & 0xFF; + + gGdtEntries[num].limit_low = (limit & 0xFFFF); + gGdtEntries[num].granularity = (limit >> 16) & 0x0F; + + gGdtEntries[num].granularity |= gran & 0xF0; + gGdtEntries[num].access = access; +} + +void irqTimer(); + +static void initializeIdt() +{ + gIdtPointer.limit = sizeof(IdtEntry) * 256 -1; + gIdtPointer.base = (uint32)&gIdtEntries; + + memset((uint8*)&gIdtEntries, 0, sizeof(IdtEntry)*256); + + // Remap the irq table. + outb(0x20, 0x11); + outb(0xA0, 0x11); + outb(0x21, 0x20); + outb(0xA1, 0x28); + outb(0x21, 0x04); + outb(0xA1, 0x02); + outb(0x21, 0x01); + outb(0xA1, 0x01); + outb(0x21, 0x0); + outb(0xA1, 0x0); + + setIdtEntry( 0, (uint32)isr0 , 0x08, 0x8E); + setIdtEntry( 1, (uint32)isr1 , 0x08, 0x8E); + setIdtEntry( 2, (uint32)isr2 , 0x08, 0x8E); + setIdtEntry( 3, (uint32)isr3 , 0x08, 0x8E); + setIdtEntry( 4, (uint32)isr4 , 0x08, 0x8E); + setIdtEntry( 5, (uint32)isr5 , 0x08, 0x8E); + setIdtEntry( 6, (uint32)isr6 , 0x08, 0x8E); + setIdtEntry( 7, (uint32)isr7 , 0x08, 0x8E); + setIdtEntry( 8, (uint32)isr8 , 0x08, 0x8E); + setIdtEntry( 9, (uint32)isr9 , 0x08, 0x8E); + setIdtEntry(10, (uint32)isr10, 0x08, 0x8E); + setIdtEntry(11, (uint32)isr11, 0x08, 0x8E); + setIdtEntry(12, (uint32)isr12, 0x08, 0x8E); + setIdtEntry(13, (uint32)isr13, 0x08, 0x8E); + setIdtEntry(14, (uint32)isr14, 0x08, 0x8E); + setIdtEntry(15, (uint32)isr15, 0x08, 0x8E); + setIdtEntry(16, (uint32)isr16, 0x08, 0x8E); + setIdtEntry(17, (uint32)isr17, 0x08, 0x8E); + setIdtEntry(18, (uint32)isr18, 0x08, 0x8E); + setIdtEntry(19, (uint32)isr19, 0x08, 0x8E); + setIdtEntry(20, (uint32)isr20, 0x08, 0x8E); + setIdtEntry(21, (uint32)isr21, 0x08, 0x8E); + setIdtEntry(22, (uint32)isr22, 0x08, 0x8E); + setIdtEntry(23, (uint32)isr23, 0x08, 0x8E); + setIdtEntry(24, (uint32)isr24, 0x08, 0x8E); + setIdtEntry(25, (uint32)isr25, 0x08, 0x8E); + setIdtEntry(26, (uint32)isr26, 0x08, 0x8E); + setIdtEntry(27, (uint32)isr27, 0x08, 0x8E); + setIdtEntry(28, (uint32)isr28, 0x08, 0x8E); + setIdtEntry(29, (uint32)isr29, 0x08, 0x8E); + setIdtEntry(30, (uint32)isr30, 0x08, 0x8E); + setIdtEntry(31, (uint32)isr31, 0x08, 0x8E); + + setIdtEntry(32, (uint32)irqTimer, 0x08, 0x8E); + setIdtEntry(33, (uint32)irq1, 0x08, 0x8E); + setIdtEntry(34, (uint32)irq2, 0x08, 0x8E); + setIdtEntry(35, (uint32)irq3, 0x08, 0x8E); + setIdtEntry(36, (uint32)irq4, 0x08, 0x8E); + setIdtEntry(37, (uint32)irq5, 0x08, 0x8E); + setIdtEntry(38, (uint32)irq6, 0x08, 0x8E); + setIdtEntry(39, (uint32)irq7, 0x08, 0x8E); + setIdtEntry(40, (uint32)irq8, 0x08, 0x8E); + setIdtEntry(41, (uint32)irq9, 0x08, 0x8E); + setIdtEntry(42, (uint32)irq10, 0x08, 0x8E); + setIdtEntry(43, (uint32)irq11, 0x08, 0x8E); + setIdtEntry(44, (uint32)irq12, 0x08, 0x8E); + setIdtEntry(45, (uint32)irq13, 0x08, 0x8E); + setIdtEntry(46, (uint32)irq14, 0x08, 0x8E); + setIdtEntry(47, (uint32)irq15, 0x08, 0x8E); + setIdtEntry(128, (uint32)isr128, 0x08, 0x8E); + + flushIdt((uint32)&gIdtPointer); +} + +static void setIdtEntry(uint8 num, uint32 base, uint16 sel, uint8 flags) +{ + gIdtEntries[num].base_lo = base & 0xFFFF; + gIdtEntries[num].base_hi = (base >> 16) & 0xFFFF; + + gIdtEntries[num].sel = sel; + gIdtEntries[num].always0 = 0; + gIdtEntries[num].flags = flags | 0x60; +} + +static void handleDoubleFault(Registers *regs) +{ + printkf("Double fault!!! Error code:%d\n", regs->errorCode); + + PANIC("Double fault!!!"); +} + +static void handleGeneralProtectionFault(Registers *regs) +{ + printkf("General protection fault!!! Error code:%d - IP:%x\n", regs->errorCode, regs->eip); + + Thread* faultingThread = getCurrentThread(); + if (NULL != faultingThread) + { + Thread* mainThread = getMainKernelThread(); + + if (mainThread == faultingThread) + { + PANIC("General protection fault in Kernel main thread!!!"); + } + else + { + printkf("Faulting thread is %d\n", faultingThread->threadId); + + if (faultingThread->userMode) + { + printkf("Destroying process %d\n", faultingThread->owner->pid); + + destroyProcess(faultingThread->owner); + } + else + { + printkf("Destroying kernel thread %d\n", faultingThread->threadId); + + destroyThread(faultingThread); + } + + waitForSchedule(); + } + } + else + { + PANIC("General protection fault!!!"); + } +} -- cgit 1.4.1-2-gfad0