Um monte de mudanças, adicionado o idt e o gdt e melhorias no

multiboot.

Modificado a inicialização também.

src/kernel/arch/i386/isa_specific_code.cpp

@@ -0,0 +1,52 @@
+
+#include	<isa_specific_code.hpp>
+#include	<kernel/gdt.hpp>
+
+#include	<stdint.h>
+
+extern "C" {
+	void GDT_flush( const GDT_ptr &new_gdt ){
+		asm volatile ("lgdt (%0)" : : "dN" (&new_gdt) );
+		asm volatile ("mov $0x10, %ax\n\t"
+			"mov %ax, %ds\n\t"
+			"mov %ax, %es\n\t"
+			"mov %ax, %fs\n\t"
+			"mov %ax, %gs\n\t"
+			"mov %ax, %ss\n\t"
+			"ljmp  $0x8,$gdt_jmp_flush\n"
+			"gdt_jmp_flush:\n\t"
+		);
+	}
+
+	void IDT_load( const IDT_ptr &new_idt ){
+		asm volatile ("lidt (%0)" : : "dN" (&new_idt) );
+	}
+
+	void halt_machine(){
+		asm(".hang:\n\t"
+		"hlt\n\t"
+		"jmp  .hang");
+	}
+
+	void disable_interrupts(){
+		asm("cli");
+	}
+
+	// Write a byte out to the specified port.
+	void outb(const uint16_t &port, const uint8_t &value){
+		asm volatile ("outb %1, %0" : : "dN" (port), "a" (value));
+	}
+
+	uint8_t inb(const uint16_t &port){
+		uint8_t ret;
+		asm volatile("inb %1, %0" : "=a" (ret) : "dN" (port));
+		return ret;
+	}
+
+	uint16_t inw(const uint16_t &port){
+		uint16_t ret;
+		asm volatile ("inw %1, %0" : "=a" (ret) : "dN" (port));
+		return ret;
+	}
+}
+

src/kernel/boot/multiboot.hpp

@@ -0,0 +1,228 @@
+/* multiboot.h - Multiboot header file. */
+/* Copyright (C) 1999,2003,2007,2008,2009  Free Software Foundation, Inc.
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to
+ *  deal in the Software without restriction, including without limitation the
+ *  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ *  sell copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in
+ *  all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL ANY
+ *  DEVELOPER OR DISTRIBUTOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+ *  IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef MULTIBOOT_HEADER
+#define MULTIBOOT_HEADER 1
+
+/* How many bytes from the start of the file we search for the header. */
+#define MULTIBOOT_SEARCH                        8192
+
+/* The magic field should contain this. */
+#define MULTIBOOT_HEADER_MAGIC                  0x1BADB002
+
+/* This should be in %eax. */
+#define MULTIBOOT_BOOTLOADER_MAGIC              0x2BADB002
+
+/* The bits in the required part of flags field we don't support. */
+#define MULTIBOOT_UNSUPPORTED                   0x0000fffc
+
+/* Alignment of multiboot modules. */
+#define MULTIBOOT_MOD_ALIGN                     0x00001000
+
+/* Alignment of the multiboot info structure. */
+#define MULTIBOOT_INFO_ALIGN                    0x00000004
+
+/* Flags set in the 'flags' member of the multiboot header. */
+
+/* Align all boot modules on i386 page (4KB) boundaries. */
+#define MULTIBOOT_PAGE_ALIGN                    0x00000001
+
+/* Must pass memory information to OS. */
+#define MULTIBOOT_MEMORY_INFO                   0x00000002
+
+/* Must pass video information to OS. */
+#define MULTIBOOT_VIDEO_MODE                    0x00000004
+
+/* This flag indicates the use of the address fields in the header. */
+#define MULTIBOOT_AOUT_KLUDGE                   0x00010000
+
+/* Flags to be set in the 'flags' member of the multiboot info structure. */
+
+/* is there basic lower/upper memory information? */
+#define MULTIBOOT_INFO_MEMORY                   0x00000001
+/* is there a boot device set? */
+#define MULTIBOOT_INFO_BOOTDEV                  0x00000002
+/* is the command-line defined? */
+#define MULTIBOOT_INFO_CMDLINE                  0x00000004
+/* are there modules to do something with? */
+#define MULTIBOOT_INFO_MODS                     0x00000008
+
+/* These next two are mutually exclusive */
+
+/* is there a symbol table loaded? */
+#define MULTIBOOT_INFO_AOUT_SYMS                0x00000010
+/* is there an ELF section header table? */
+#define MULTIBOOT_INFO_ELF_SHDR                 0X00000020
+
+/* is there a full memory map? */
+#define MULTIBOOT_INFO_MEM_MAP                  0x00000040
+
+/* Is there drive info? */
+#define MULTIBOOT_INFO_DRIVE_INFO               0x00000080
+
+/* Is there a config table? */
+#define MULTIBOOT_INFO_CONFIG_TABLE             0x00000100
+
+/* Is there a boot loader name? */
+#define MULTIBOOT_INFO_BOOT_LOADER_NAME         0x00000200
+
+/* Is there a APM table? */
+#define MULTIBOOT_INFO_APM_TABLE                0x00000400
+
+/* Is there video information? */
+#define MULTIBOOT_INFO_VIDEO_INFO               0x00000800
+
+#ifndef ASM_FILE
+
+#include	<stdint.h>
+
+//typedef unsigned short          multiboot_uint16_t;
+//typedef unsigned int            multiboot_uint32_t;
+//typedef unsigned long long      multiboot_uint64_t;
+
+typedef uint16_t	multiboot_uint16_t;
+typedef uint32_t	multiboot_uint32_t;
+typedef uint64_t	multiboot_uint64_t;
+
+struct multiboot_header{
+	/* Must be MULTIBOOT_MAGIC - see above. */
+	const multiboot_uint32_t magic;
+
+	/* Feature flags. */
+	const multiboot_uint32_t flags;
+
+	/* The above fields plus this one must equal 0 mod 2^32. */
+	const multiboot_uint32_t checksum;
+
+	/* These are only valid if MULTIBOOT_AOUT_KLUDGE is set. */
+	const multiboot_uint32_t header_addr;
+	const multiboot_uint32_t load_addr;
+	const multiboot_uint32_t load_end_addr;
+	const multiboot_uint32_t bss_end_addr;
+	const multiboot_uint32_t entry_addr;
+
+	/* These are only valid if MULTIBOOT_VIDEO_MODE is set. */
+	multiboot_uint32_t mode_type;
+	multiboot_uint32_t width;
+	multiboot_uint32_t height;
+	multiboot_uint32_t depth;
+};
+
+/* The symbol table for a.out. */
+struct multiboot_aout_symbol_table
+{
+	multiboot_uint32_t tabsize;
+	multiboot_uint32_t strsize;
+	multiboot_uint32_t addr;
+	multiboot_uint32_t reserved;
+};
+typedef struct multiboot_aout_symbol_table multiboot_aout_symbol_table_t;
+
+/* The section header table for ELF. */
+struct multiboot_elf_section_header_table
+{
+	multiboot_uint32_t num;
+	multiboot_uint32_t size;
+	multiboot_uint32_t addr;
+	multiboot_uint32_t shndx;
+};
+typedef struct multiboot_elf_section_header_table multiboot_elf_section_header_table_t;
+
+struct multiboot_info
+{
+	/* Multiboot info version number */
+	multiboot_uint32_t flags;
+
+	/* Available memory from BIOS */
+	multiboot_uint32_t mem_lower;
+	multiboot_uint32_t mem_upper;
+
+	/* "root" partition */
+	multiboot_uint32_t boot_device;
+
+	/* Kernel command line */
+	multiboot_uint32_t cmdline;
+
+	/* Boot-Module list */
+	multiboot_uint32_t mods_count;
+	multiboot_uint32_t mods_addr;
+
+	union
+	{
+		multiboot_aout_symbol_table_t aout_sym;
+		multiboot_elf_section_header_table_t elf_sec;
+	} u;
+
+	/* Memory Mapping buffer */
+	multiboot_uint32_t mmap_length;
+	multiboot_uint32_t mmap_addr;
+
+	/* Drive Info buffer */
+	multiboot_uint32_t drives_length;
+	multiboot_uint32_t drives_addr;
+
+	/* ROM configuration table */
+	multiboot_uint32_t config_table;
+
+	/* Boot Loader Name */
+	multiboot_uint32_t boot_loader_name;
+
+	/* APM table */
+	multiboot_uint32_t apm_table;
+
+	/* Video */
+	multiboot_uint32_t vbe_control_info;
+	multiboot_uint32_t vbe_mode_info;
+	multiboot_uint16_t vbe_mode;
+	multiboot_uint16_t vbe_interface_seg;
+	multiboot_uint16_t vbe_interface_off;
+	multiboot_uint16_t vbe_interface_len;
+};
+typedef struct multiboot_info multiboot_info_t;
+
+struct multiboot_mmap_entry
+{
+	multiboot_uint32_t size;
+	multiboot_uint64_t addr;
+	multiboot_uint64_t len;
+#define MULTIBOOT_MEMORY_AVAILABLE              1
+#define MULTIBOOT_MEMORY_RESERVED               2
+	multiboot_uint32_t type;
+} __attribute__((packed));
+typedef struct multiboot_mmap_entry multiboot_memory_map_t;
+
+struct multiboot_mod_list
+{
+	/* the memory used goes from bytes 'mod_start' to 'mod_end-1' inclusive */
+	multiboot_uint32_t mod_start;
+	multiboot_uint32_t mod_end;
+
+	/* Module command line */
+	multiboot_uint32_t cmdline;
+
+	/* padding to take it to 16 bytes (must be zero) */
+	multiboot_uint32_t pad;
+};
+typedef struct multiboot_mod_list multiboot_module_t;
+
+#endif /* ! ASM_FILE */
+
+#endif /* ! MULTIBOOT_HEADER */

src/kernel/gdt.cpp

@@ -0,0 +1,51 @@
+
+#include	<kernel/gdt.hpp>
+#include	<isa_specific_code.hpp>
+
+GDT::GDT(){}
+
+/* Setup a descriptor in the Global Descriptor Table */
+void GDT::set_gate(int num, unsigned long base, unsigned long limit, unsigned char access, unsigned char gran){
+	/* Setup the descriptor base address */
+	this->gdt[num].base_low = (base & 0xFFFF);
+	this->gdt[num].base_middle = (base >> 16) & 0xFF;
+	this->gdt[num].base_high = (base >> 24) & 0xFF;
+
+	/* Setup the descriptor limits */
+	gdt[num].limit_low = (limit & 0xFFFF);
+	gdt[num].granularity = ((limit >> 16) & 0x0F);
+
+	/* Finally, set up the granularity and access flags */
+	gdt[num].granularity |= (gran & 0xF0);
+	gdt[num].access = access;
+}
+
+/* Should be called by main. This will setup the special GDT
+ *  pointer, set up the first 3 entries in our GDT, and then
+ *  finally call gdt_flush() in our assembler file in order
+ *  to tell the processor where the new GDT is and update the
+ *  new segment registers */
+void GDT::install(){
+	/* Setup the GDT pointer and limit */
+	this->gp.limit = (sizeof(struct GDT_entry) * 3) - 1;
+	this->gp.base = (uint32_t)(&(this->gdt));
+
+	/* Our NULL descriptor */
+	this->set_gate(0, 0, 0, 0, 0);
+
+	/* The second entry is our Code Segment. The base address
+	 *  is 0, the limit is 4GBytes, it uses 4KByte granularity,
+	 *  uses 32-bit opcodes, and is a Code Segment descriptor.
+	 *  Please check the table above in the tutorial in order
+	 *  to see exactly what each value means */
+	this->set_gate(1, 0, 0xFFFFFFFF, 0x9A, 0xCF);
+
+	/* The third entry is our Data Segment. It's EXACTLY the
+	 *  same as our code segment, but the descriptor type in
+	 *  this entry's access byte says it's a Data Segment */
+	this->set_gate(2, 0, 0xFFFFFFFF, 0x92, 0xCF);
+
+	/* Flush out the old GDT and install the new changes! */
+	GDT_flush( this->gp );
+}
+