Initialize boot CPU structures inside kernel on AMD64

2023-01-29 00:45:17 +01:00
parent 8733a23b20
commit 7bf4a9ab8d
9 changed files with 272 additions and 0 deletions
--- a/xtoskrnl/ar/amd64/procsup.c
+++ b/xtoskrnl/ar/amd64/procsup.c
@@ -0,0 +1,196 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            xtoskrnl/ar/amd64/procsup.c
+ * DESCRIPTION:     AMD64 processor functionality support
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#include "xtos.h"
+
+
+/**
+ * Initializes AMD64 processor specific structures.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+ArInitializeProcessor(VOID)
+{
+    PKGDTENTRY Gdt;
+    PKTSS Tss;
+    KDESCRIPTOR GdtDescriptor;
+
+    /* Use initial structures */
+    Gdt = ArInitialGdt;
+    Tss = &ArInitialTss;
+
+    /* Initialize GDT and TSS */
+    ArpInitializeGdt(Gdt);
+    ArpInitializeTss(Tss, Gdt);
+
+    /* Set GDT descriptor */
+    GdtDescriptor.Base = Gdt;
+    GdtDescriptor.Limit = (GDT_ENTRIES * sizeof(PKGDTENTRY)) - 1;
+
+    /* Load GDT and TSS */
+    ArLoadGlobalDescriptorTable(&GdtDescriptor.Limit);
+    ArLoadTaskRegister((UINT32)KGDT_SYS_TSS);
+}
+
+/**
+ * Initializes the kernel's Global Descriptor Table (GDT).
+ *
+ * @param Gdt
+ *        Supplies a pointer to the GDT to use.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+ArpInitializeGdt(IN PKGDTENTRY Gdt)
+{
+    /* Initialize GDT entries */
+    ArpInitializeGdtEntry(Gdt, KGDT_NULL, 0x0, 0x0, 0, KGDT_DPL_SYSTEM, 0);
+    ArpInitializeGdtEntry(Gdt, KGDT_R0_CODE, 0x0, 0x0, KGDT_TYPE_CODE, KGDT_DPL_SYSTEM, 0);
+    ArpInitializeGdtEntry(Gdt, KGDT_R0_DATA, 0x0, 0x0, KGDT_TYPE_DATA, KGDT_DPL_SYSTEM, 0);
+    ArpInitializeGdtEntry(Gdt, KGDT_R3_CODE, 0x0, 0x0, KGDT_TYPE_CODE, KGDT_DPL_USER, 0);
+    ArpInitializeGdtEntry(Gdt, KGDT_R3_DATA, 0x0, 0xFFFFFFFF, KGDT_TYPE_DATA, KGDT_DPL_USER, 2);
+    ArpInitializeGdtEntry(Gdt, KGDT_R3_CMCODE, 0x0, 0xFFFFFFFF, KGDT_TYPE_CODE, KGDT_DPL_USER, 2);
+    ArpInitializeGdtEntry(Gdt, KGDT_R3_CMTEB, 0x0, 0x0FFF, KGDT_TYPE_DATA, KGDT_DPL_USER, 2);
+    ArpInitializeGdtEntry(Gdt, KGDT_R0_LDT, 0, 0xFFFFFFFF, KGDT_TYPE_CODE, KGDT_DPL_SYSTEM, 0);
+    ArpInitializeGdtEntry(Gdt, KGDT_SYS_TSS, 0, sizeof(KTSS), AMD64_TSS, KGDT_DPL_SYSTEM, 0);
+}
+
+/**
+ * Fills in an AMD64 GDT entry.
+ *
+ * @param Gdt
+ *        Supplies a pointer to the GDT.
+ *
+ * @param Selector
+ *        Specifies a segment selector of the GDT entry.
+ *
+ * @param Base
+ *        Specifies a base address value of the descriptor.
+ *
+ * @param Limit
+ *        Specifies a descriptor limit.
+ *
+ * @param Type
+ *        Specifies a type of the descriptor.
+ *
+ * @param Dpl
+ *        Specifies the descriptor privilege level.
+ *
+ * @param SegmentMode
+ *        Specifies a segment mode of the descriptor.
+ *
+ * @return This routine does not return any value
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+ArpInitializeGdtEntry(IN PKGDTENTRY Gdt,
+                      IN USHORT Selector,
+                      IN ULONGLONG Base,
+                      IN ULONG Limit,
+                      IN UCHAR Type,
+                      IN UCHAR Dpl,
+                      IN UCHAR SegmentMode)
+{
+    PKGDTENTRY GdtEntry;
+    UCHAR Granularity;
+
+    /* Set the granularity flag depending on descriptor limit */
+    if(Limit < 0x100000)
+    {
+        /* Limit is in 1B blocks */
+        Granularity = 0;
+    }
+    else
+    {
+        /* Limit is in 4KB blocks */
+        Granularity = 1;
+        Limit >>= 12;
+    }
+
+    /* Get GDT entry */
+    GdtEntry = (PKGDTENTRY)((ULONG64)Gdt + (Selector & ~RPL_MASK));
+
+    /* Set GDT descriptor base */
+    GdtEntry->BaseLow = Base & 0xFFFF;
+    GdtEntry->Bits.BaseMiddle = (Base >> 16) & 0xFF;
+    GdtEntry->Bits.BaseHigh = (Base >> 24) & 0xFF;
+    GdtEntry->BaseUpper = Base >> 32;
+
+    /* Set descriptor limit */
+    GdtEntry->LimitLow = Limit & 0xFFFF;
+    GdtEntry->Bits.LimitHigh = (Limit >> 16) & 0xF;
+
+    /* Initialize GDT entry */
+    GdtEntry->Bits.DefaultBig = (SegmentMode & 2);
+    GdtEntry->Bits.Dpl = (Dpl & 0x3);
+    GdtEntry->Bits.Granularity = Granularity;
+    GdtEntry->Bits.LongMode = (SegmentMode & 1);
+    GdtEntry->Bits.Present = (Type != 0);
+    GdtEntry->Bits.System = 0;
+    GdtEntry->Bits.Type = (Type & 0x1F);
+    GdtEntry->MustBeZero = 0;
+}
+
+/**
+ * Initializes the kernel's Task State Segment (TSS).
+ *
+ * @param Tss
+ *        Supplies a pointer to the TSS to use.
+ *
+ * @param Gdt
+ *        Supplies a pointer to the GDT to use.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+ArpInitializeTss(IN PKTSS Tss,
+                 IN PKGDTENTRY Gdt)
+{
+    PKGDTENTRY TssEntry;
+
+    /* Get TSS entry from GDT */
+    TssEntry = (PKGDTENTRY)(&(Gdt[KGDT_SYS_TSS / sizeof(KGDTENTRY)]));
+
+    /* Initialize TSS entry */
+    TssEntry->BaseLow = (ULONG64)Tss & 0xFFFF;
+    TssEntry->BaseUpper = (ULONG64)Tss >> 32;
+    TssEntry->LimitLow = (sizeof(KTSS) - 1) & 0xFFFF;
+    TssEntry->Bits.BaseMiddle = ((ULONG64)Tss >> 16) & 0xFF;
+    TssEntry->Bits.BaseHigh = ((ULONG64)Tss >> 24) & 0xFF;
+    TssEntry->Bits.LimitHigh = (sizeof(KTSS) - 1) >> 16;
+    TssEntry->Bits.DefaultBig = 0;
+    TssEntry->Bits.Dpl = 0;
+    TssEntry->Bits.Granularity = 0;
+    TssEntry->Bits.LongMode = 0;
+    TssEntry->Bits.Present = 1;
+    TssEntry->Bits.System = 0;
+    TssEntry->Bits.Type = AMD64_TSS;
+    TssEntry->MustBeZero = 0;
+
+    /* Fill TSS with zeroes */
+    RtlZeroMemory(Tss, sizeof(KTSS));
+
+    /* Setup I/O map and stacks for ring0 & traps */
+    Tss->IoMapBase = sizeof(KTSS);
+    Tss->Rsp0 = KeInitializationBlock->KernelBootStack;
+    Tss->Ist[1] = KeInitializationBlock->KernelFaultStack;
+    Tss->Ist[2] = KeInitializationBlock->KernelFaultStack;
+    Tss->Ist[3] = KeInitializationBlock->KernelFaultStack;
+}