Some assorted in-progress work.

CMakeLists.txt

@@ -11,6 +11,10 @@ set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
 SET(CMAKE_SYSTEM_NAME Generic)
 SET(CMAKE_CROSSCOMPILING 1)
 
+enable_language(ASM)
+enable_language(C)
+enable_language(CXX)
+
 project(chroma)
 
 SET(src_files
@@ -29,11 +33,13 @@ SET(src_files
         ${CMAKE_SOURCE_DIR}/src/system/memory/liballoc.cpp
         ${CMAKE_SOURCE_DIR}/src/system/memory/physmem.c
         ${CMAKE_SOURCE_DIR}/src/system/process/process.cpp
+        ${CMAKE_SOURCE_DIR}/src/system/extern/extern_defs.cpp
         ${CMAKE_SOURCE_DIR}/src/drivers/elf.cpp
         ${CMAKE_SOURCE_DIR}/src/drivers/devices/devices.cpp
         ${CMAKE_SOURCE_DIR}/src/drivers/devices/input/keyboard.cpp
         ${CMAKE_SOURCE_DIR}/src/drivers/devices/io/apic.cpp
         ${CMAKE_SOURCE_DIR}/src/drivers/devices/storage/ata.cpp
+        ${CMAKE_SOURCE_DIR}/src/global/core-att.s
 )
 
 SET(lib_files
@@ -50,6 +56,9 @@ SET(src_no_sse
         ${CMAKE_SOURCE_DIR}/src/system/interrupts.cpp
 )
 
+SET(src_as
+        )
+
 SET(src_preamble
         ${CMAKE_SOURCE_DIR}/src/global/crt0.o
         ${CMAKE_SOURCE_DIR}/src/global/crti.o
@@ -69,6 +78,6 @@ set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_SOURCE_DIR}/bin)
 
 add_executable(kernel)
 
-target_sources(kernel PUBLIC ${src_preamble} PUBLIC ${src_files} PUBLIC ${src_no_sse} PUBLIC ${lib_files} PUBLIC ${src_epilogue})
+target_sources(kernel PUBLIC ${src_preamble} PUBLIC ${src_files} PUBLIC ${src_no_sse} PUBLIC ${lib_files} PUBLIC ${src_as} PUBLIC ${src_epilogue})
-target_compile_options(kernel PRIVATE -ffreestanding -O0 -Wall -Wextra -Wall -Werror -fPIC -fno-exceptions -fno-omit-frame-pointer -mno-red-zone -fno-stack-protector -fno-rtti -ggdb3)
+target_compile_options(kernel PRIVATE -ffreestanding -O0 -Wall -Wextra -Wall -Werror -fPIC -fno-exceptions -fno-omit-frame-pointer -mno-red-zone -fno-stack-protector $<$<COMPILE_LANGUAGE:CXX>:-fno-rtti> -ggdb3)
 target_link_options(kernel PRIVATE -T ${CMAKE_SOURCE_DIR}/linker.ld -ffreestanding -O2 -nostdlib -nostartfiles -lgcc)

src/global/core-att.s

@@ -0,0 +1,128 @@
+#************************
+#*** Team Kitty, 2021 ***
+#***     Chroma       ***
+#************************
+
+# Initial startup routines for new cores.
+# New cores start in 16 bit real mode.
+# Because of this, this is the only necessary assembler file in the OS.
+
+# First, bring them up to Protected and Long mode.
+# Then enable all necessary auxiliary features.
+# Pass off to the CPP code to handle the heavy work, we just want the core running.
+
+.code16
+.equ BASE, 0x1000
+
+.global stack
+.extern initcpu
+
+.extern coreidt
+.extern CoreGDT
+
+# 16-bit startup.
+# Initialize registers.
+# Load GDT
+# Set flags
+# Immediately jump to protected mode.
+
+.global startCore
+startCore:
+    cli
+    mov $0x0, %ax
+    mov %ax, %ds
+    mov %ax, %es
+    mov %ax, %fs
+    mov %ax, %gs
+    mov %ax, %ss
+
+    lgdtl gdt_protected
+
+    mov %cr0, %eax
+    or $0x1, %ax
+    mov %eax, %cr0
+
+    ljmpl $0x8, $startCore32
+
+.code32
+
+# Protected mode setup.
+# Set page tables
+# Set PAE
+# Immediately jump to long mode.
+
+.section .text
+startCore32:
+    mov $0x10, %bx
+    mov %bx, %ds
+    mov %bx, %es
+    mov %bx, %ss
+
+    mov $0xA000, %eax
+    mov %eax, %cr3
+
+    mov %cr4, %eax          # Enable PAE
+    or $32, %eax            # 1 << 5
+    or $128, %eax           # 1 << 7
+    mov %eax, %cr4
+
+    mov $0xC0000080, %ecx
+    rdmsr
+    or $256, %eax           # 1 << 8
+    wrmsr
+
+    mov %cr0, %eax
+    or $2147483648, %eax    # 1 << 31
+    mov %eax, %cr0
+
+    lgdt gdt_long
+    ljmp $0x8, $startCore64
+
+# Long mode setup.
+# Prepare registers.
+# Set flags
+# Load the final GDT and IDT
+# Jump to the leave function.
+
+.code64
+startCore64:
+    mov $0x10, %ax
+    mov %ax, %ds
+    mov %ax, %es
+    mov %ax, %ss
+
+    mov $0x0, %ax
+    mov %ax, %ds
+    mov %ax, %gs
+
+    lgdt CoreGDT
+    lidt coreidt
+
+    mov $0x0, %rbp
+    push $0
+    popf
+
+    mov (leave), %rax
+    jmp leave
+
+# Final setup.
+# Set some flags in registers.
+# Jump into C++ code.
+
+leave:
+    push %rbp
+
+    mov %cr0, %rax
+    btr $2, %eax
+    bts $1, %eax
+    mov %rax, %cr0
+
+    mov %cr4, %rax
+    bts $9, %eax
+    bts $10, %eax
+    mov %rax, %cr4
+
+    call initcpu
+
+.global endCore
+endCore:

src/global/core.s

@@ -1,27 +1,29 @@
-;************************
+.intel_syntax noprefix
-;*** Team Kitty, 2021 ***
+#************************
-;***     Chroma       ***
+#*** Team Kitty, 2021 ***
-;************************
+#***     Chroma       ***
+#************************
 
-; Initial startup routines for new cores.
+# Initial startup routines for new cores.
-; New cores start in 16 bit real mode.
+# New cores start in 16 bit real mode.
-; Because of this, this is the only necessary assembler file in the OS.
+# Because of this, this is the only necessary assembler file in the OS.
 
-; First, bring them up to Protected and Long mode.
+# First, bring them up to Protected and Long mode.
-; Then enable all necessary auxiliary features.
+# Then enable all necessary auxiliary features.
-; Pass off to the CPP code to handle the heavy work, we just want the core running.
+# Pass off to the CPP code to handle the heavy work, we just want the core running.
 
-[bits 16]
+.intel_syntax
-BASE equ 0x1000
 
-global stack
+.code16
-extern initcpu
+.equ BASE, 0x1000
 
-extern coreidt
+.global stack
-extern coregdt
+.extern initcpu
 
-global startCore
+.extern coreidt
-startCore:
+.extern coregdt
+
+.global startCore
     cli
     mov ax, 0x0
     mov ds, ax
@@ -38,9 +40,9 @@ startCore:
 
     jmp 0x8:(startCore32 - startCore + BASE)
 
-[bits 32]
+.code32
 
-section .text
+.section .text
 startCore32:
     mov bx, 0x10
     mov ds, bx
@@ -67,7 +69,7 @@ startCore32:
     lgdt [gdt_long - startCore + BASE]
     jmp 8:(startCore64 - startCore + BASE)
 
-[bits 64]
+.code64
 startCore64:
     mov ax, 0x10
     mov ds, ax

src/system/core.cpp

@@ -25,7 +25,6 @@ extern "C" void initcpu() {
     __asm__ __volatile__("mov %%fs, %0" : : "r" (Device::APIC::driver->GetCurrentCore()) : );
 
     SerialPrintf("[CORE] Core %d ready.\r\n", Device::APIC::driver->GetCurrentCore());
-    // TODO: New GDT
     __asm__ __volatile__("cli");
     Ready = true;
     __asm__ __volatile__("sti");

src/system/cpu.cpp

@@ -44,6 +44,11 @@ __attribute__((aligned(64))) static volatile size_t InitGDT[5] = {
         0
 };
 
+__attribute__((aligned(64))) static DESC_TBL CoreGDT = {
+        .Limit = sizeof(InitGDT),
+        .Base = (size_t) InitGDT
+};
+
 __attribute__((aligned(64))) static volatile TSS64 TSSEntries;
 
 __attribute__((aligned(64))) static volatile IDT_GATE IDTEntries[256];
@@ -111,7 +116,6 @@ void PrepareCPU() {
 */
 
 void SetupInitialGDT() {
-    DESC_TBL GDTData;
     size_t TSSBase = (uint64_t) (&TSSEntries);
 
     uint16_t TSSLower = (uint16_t) TSSBase;
@@ -119,15 +123,13 @@ void SetupInitialGDT() {
     uint8_t TSSMid2 = (uint8_t) (TSSBase >> 24);
     uint32_t TSSHigher = (uint32_t) (TSSBase >> 32);
 
-    GDTData.Limit = sizeof(InitGDT) - 1;
-    GDTData.Base = (size_t) InitGDT;
 
     ((TSS_ENTRY*) (&((GDT_ENTRY*) InitGDT)[3]))->BaseLow = TSSLower;
     ((TSS_ENTRY*) (&((GDT_ENTRY*) InitGDT)[3]))->BaseMid1 = TSSMid1;
     ((TSS_ENTRY*) (&((GDT_ENTRY*) InitGDT)[3]))->BaseMid2 = TSSMid2;
     ((TSS_ENTRY*) (&((GDT_ENTRY*) InitGDT)[3]))->BaseHigh = TSSHigher;
 
-    WriteGDT(GDTData);
+    WriteGDT(CoreGDT);
     WriteTSR(3 << 3);
     RefreshCS();
 }

src/system/extern/extern_defs.cpp

@@ -0,0 +1,55 @@
+/************************
+ *** Team Kitty, 2022 ***
+ ***     Chroma       ***
+ ***********************/
+
+#include <kernel/system/descriptors.h>
+
+/**
+ * Contains definitions that are used by external files.
+ * That means, independent programs or assembler files.
+ */
+
+/**
+ * The template GDT entry for a newly initialized core.
+ * Protected Mode.
+ * TODO: Document what the entries here are.
+ */
+
+__attribute__((aligned(64))) size_t ProtectedGDTEntry[3] = {
+        0,
+        0x00CF9A000000FFFF,
+        0x00CF92000000FFFF
+};
+
+/**
+ * The GDT table value to be loaded into each newly initialized core.
+ * Protected Mode.
+ */
+
+DESC_TBL ProtectedGDT = {
+        .Limit = sizeof(ProtectedGDTEntry) - 1,
+        .Base = (size_t) &ProtectedGDTEntry
+};
+
+/**
+ * The template GDT entry for a newly initialized core.
+ * Long Mode.
+ * TODO: Document what the entries here are.
+ */
+__attribute__((aligned(64))) size_t LongGDTEntry[3] = {
+        0,
+        0x00AF98000000FFFF,
+        0x00CF92000000FFFF
+};
+
+/**
+ * The GDT table value to be loaded into each newly initialized core.
+ * Long Mode.
+ */
+
+DESC_TBL LongGDT = {
+        .Limit = sizeof(LongGDTEntry) - 1,
+        .Base = (size_t) &LongGDTEntry
+};
+

src/system/memory/physmem.c

@@ -7,6 +7,7 @@
  ***     Chroma       ***
  ***********************/
 
+
 #ifdef __cplusplus
 extern "C" {
 #endif