# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1301168354 -7200
# Node ID 098b1cb5eeaa748fb49f16adcb78c324701c301e
# Parent  2cbc2b922e49843471e2f47ea435d14a53dcf959
forgot to add a shitload of files

diff -r 2cbc2b922e49 -r 098b1cb5eeaa src/boot/mboot.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/boot/mboot.h	Sat Mar 26 21:39:14 2011 +0200
@@ -0,0 +1,103 @@
+#ifndef MBOOT_H_
+#define MBOOT_H_
+
+#include <inttypes.h>
+
+#define MB_MEM		(1 << 0)
+#define MB_BOOTDEV	(1 << 1)
+#define MB_CMDLINE	(1 << 2)
+#define MB_MODULES	(1 << 3)
+#define MB_AOUT_SYM	(1 << 4)
+#define MB_ELF_SHDR	(1 << 5)
+#define MB_MMAP		(1 << 6)
+#define MB_DRIVES	(1 << 7)
+#define MB_CFGTAB	(1 << 8)
+#define MB_LDRNAME	(1 << 9)
+#define MB_APM		(1 << 10)
+#define MB_GFX		(1 << 11)
+
+#define MB_MEM_VALID	1
+#define MB_DRIVE_CHS	0
+#define MB_DRIVE_LBA	1
+
+struct mboot_module {
+	uint32_t start_addr, end_addr;
+	char *str;
+	uint32_t reserved;
+};
+
+struct mboot_elf_shdr_table {
+	uint32_t num;
+	uint32_t size;
+	uint32_t addr;
+	uint32_t shndx;
+};
+
+struct mboot_mmap {
+	uint32_t skip;
+	uint32_t base_low, base_high;
+	uint32_t length_low, length_high;
+	uint32_t type;
+};
+
+struct mboot_drive {
+	uint32_t size;
+	uint8_t id;
+	uint8_t mode;
+	uint16_t cyl;
+	uint8_t heads, sect;
+	uint16_t ports[1];	/* zero-terminated */
+} __attribute__ ((packed));
+
+struct mboot_apm {
+	uint16_t ver;
+	uint16_t cseg;
+	uint32_t offs;
+	uint16_t cseg16;
+	uint16_t dseg;
+	uint16_t flags;
+	uint16_t cseg_len;
+	uint16_t cseg16_len;
+	uint16_t dseg_len;
+} __attribute__ ((packed));
+
+struct mboot_vbe {
+	uint32_t ctl_info;
+	uint32_t mode_info;
+	uint16_t mode;
+	uint16_t ifseg, ifoffs, iflen;
+} __attribute__ ((packed));
+
+
+/* multiboot information structure */
+struct mboot_info {
+	uint32_t flags;
+	/* mem_lower: available low memory (up to 640kb)
+	 * mem_upper: available upper memory (from 1mb and upwards)
+	 */
+	uint32_t mem_lower, mem_upper;
+	/* boot device fields: MSB -> [part3|part2|part1|drive] <- LSB */
+	uint32_t boot_dev;
+	char *cmdline;
+	/* loaded kernel modules */
+	uint32_t mods_count;
+	struct mboot_module *mods;
+	/* elf sections table */
+	struct mboot_elf_shdr_table elf;
+	/* memory map */
+	uint32_t mmap_len;
+	struct mboot_mmap *mmap;
+	/* drives table */
+	uint32_t drives_len;
+	struct mboot_drive *drives;
+	/* address of BIOS ROM configuration table */
+	uint32_t cfgtable;
+	char *boot_loader_name;
+	/* advanced power management */
+	struct mboot_apm *apm;
+	/* video bios extensions */
+	struct mboot_vbe vbe;
+};
+
+
+#endif	/* MBOOT_H_ */
diff -r 2cbc2b922e49 -r 098b1cb5eeaa src/mem.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mem.c	Sat Mar 26 21:39:14 2011 +0200
@@ -0,0 +1,40 @@
+#include <stdio.h>
+#include "mem.h"
+#include "panic.h"
+#include "vm.h"
+
+/* end of kernel image */
+extern int _end;
+
+static uint32_t brk;
+
+void init_mem(struct mboot_info *mb)
+{
+	/* start the physical allocated break at the end of
+	 * the kernel image
+	 */
+	brk = (uint32_t)&_end;
+}
+
+uint32_t alloc_phys_page(void)
+{
+	uint32_t addr, dbg_prev_brk;
+
+	if(ADDR_TO_PGOFFS(brk)) {
+		/* brk is not aligned, find the next page-aligned address */
+		addr = (brk + PGSIZE) & ~PGOFFS_MASK;
+	} else {
+		/* brk is aligned, so we can use that address directly */
+		addr = brk;
+	}
+
+	if(addr >= MAX_BRK) {
+		panic("alloc_phys_page() out of early alloc space");
+	}
+
+	dbg_prev_brk = brk;
+	brk = addr + PGSIZE;	/* move the break to the end of the page */
+
+	printf("DBG: alloc_phys_page(): %x  (brk %x -> %x)\n", addr, dbg_prev_brk, brk);
+	return addr;
+}
diff -r 2cbc2b922e49 -r 098b1cb5eeaa src/mem.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mem.h	Sat Mar 26 21:39:14 2011 +0200
@@ -0,0 +1,12 @@
+#ifndef MEM_H_
+#define MEM_H_
+
+#include "mboot.h"
+
+/* maximum break for the early allocator */
+#define MAX_BRK		0x400000
+
+void init_mem(struct mboot_info *mb);
+uint32_t alloc_phys_page(void);
+
+#endif	/* MEM_H_ */
diff -r 2cbc2b922e49 -r 098b1cb5eeaa src/vm-asm.S
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vm-asm.S	Sat Mar 26 21:39:14 2011 +0200
@@ -0,0 +1,27 @@
+	.text
+/* enable_paging(void)
+ * sets the cr0 bit 31 which enables page translation */
+	.globl enable_paging
+enable_paging:
+	movl %cr0, %eax
+	orl $0x80000000, %eax
+	movl %eax, %cr0
+	ret
+
+/* set_pgdir_addr(uint32_t addr)
+ * sets the address of the page directory by writing to cr3, which
+ * also results in a TLB flush. */
+	.globl set_pgdir_addr
+set_pgdir_addr:
+	movl 4(%esp), %eax
+	movl %eax, %cr3
+	ret
+
+/* get_fault_addr(void)
+ * returns the contents of control register 2, which provides
+ * the faulting address during a page fault exception
+ */
+	.globl get_fault_addr
+get_fault_addr:
+	movl %cr2, %eax
+	ret
diff -r 2cbc2b922e49 -r 098b1cb5eeaa src/vm.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vm.c	Sat Mar 26 21:39:14 2011 +0200
@@ -0,0 +1,147 @@
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+#include "vm.h"
+#include <stdio.h>
+#include "intr.h"
+#include "mem.h"
+#include "panic.h"
+
+
+/* defined in vm-asm.S */
+void enable_paging(void);
+void set_pgdir_addr(uint32_t addr);
+uint32_t get_fault_addr(void);
+
+static void pgfault(int inum, uint32_t err);
+
+/* page directory */
+static uint32_t pgdir[1024];
+
+#define KMEM_START		0xc0000000
+#define IDMAP_START		0xa0000
+
+#define ATTR_PGDIR_MASK	0x3f
+#define ATTR_PGTBL_MASK	0x1ff
+#define ADDR_PGENT_MASK	0xfffff000
+
+#define PAGEFAULT		14
+
+void init_vm(struct mboot_info *mb)
+{
+	init_mem(mb);
+
+	memset(pgdir, 0, sizeof pgdir);
+
+	/* map the video memory and kernel code 1-1 */
+	map_mem_range(IDMAP_START, MAX_BRK - IDMAP_START, IDMAP_START, 0);
+
+	interrupt(PAGEFAULT, pgfault);
+
+	set_pgdir_addr((int32_t)pgdir);
+	enable_paging();
+}
+
+void map_page(int vpage, int ppage, unsigned int attr)
+{
+	uint32_t *pgtbl;
+	int diridx = PAGE_TO_PGTBL(vpage);
+	int pgidx = PAGE_TO_PGTBL_PG(vpage);
+
+	if(!(pgdir[diridx] & PG_PRESENT)) {
+		uint32_t addr = alloc_phys_page();
+		pgtbl = (uint32_t*)addr;
+		pgdir[diridx] = addr | (attr & ATTR_PGDIR_MASK) | PG_PRESENT;
+	} else {
+		pgtbl = (uint32_t*)(pgdir[diridx] & ADDR_PGENT_MASK);
+	}
+
+	pgtbl[pgidx] = PAGE_TO_ADDR(ppage) | (attr & ATTR_PGTBL_MASK) | PG_PRESENT;
+}
+
+void unmap_page(int vpage)
+{
+	uint32_t *pgtbl;
+	int diridx = PAGE_TO_PGTBL(vpage);
+	int pgidx = PAGE_TO_PGTBL_PG(vpage);
+
+	if(!(pgdir[diridx] & PG_PRESENT)) {
+		goto err;
+	}
+	pgtbl = (uint32_t*)(pgdir[diridx] & ADDR_PGENT_MASK);
+
+	if(!(pgtbl[pgidx] & PG_PRESENT)) {
+		goto err;
+	}
+	pgtbl[pgidx] = 0;
+
+	return;
+err:
+	printf("unmap_page(%d): page already not mapped\n", vpage);
+}
+
+void map_page_range(int vpg_start, int pgcount, int ppg_start, unsigned int attr)
+{
+	int i;
+
+	for(i=0; i<pgcount; i++) {
+		map_page(vpg_start + i, ppg_start + i, attr);
+	}
+}
+
+void map_mem_range(uint32_t vaddr, size_t sz, uint32_t paddr, unsigned int attr)
+{
+	int vpg_start, ppg_start, num_pages;
+
+	if(!sz) return;
+
+	if(ADDR_TO_PGOFFS(paddr)) {
+		panic("map_mem_range called with unaligned physical address: %x\n", paddr);
+	}
+
+	vpg_start = ADDR_TO_PAGE(vaddr);
+	ppg_start = ADDR_TO_PAGE(paddr);
+	num_pages = ADDR_TO_PAGE(sz) + 1;
+
+	map_page_range(vpg_start, num_pages, ppg_start, attr);
+}
+
+
+/*	if(mb->flags & MB_MMAP) {
+		struct mboot_mmap *mem, *mmap_end;
+
+		mem = mb->mmap;
+		mmap_end = (struct mboot_mmap*)((char*)mb->mmap + mb->mmap_len);
+
+		printf("memory map:\n");
+		while(mem < mmap_end) {
+			unsigned int end = mem->base_low + mem->length_low;
+			char *type = mem->type == MB_MEM_VALID ? "free:" : "hole:";
+
+			printf("  %s %x - %x (%u bytes)\n", type, mem->base_low, end, mem->length_low);
+			mem = (struct mboot_mmap*)((char*)mem + mem->skip + sizeof mem->skip);
+		}
+	}
+
+	if(mb->flags & MB_MEM) {
+		printf("lower memory: %ukb, upper mem: %ukb\n", mb->mem_lower, mb->mem_upper);
+	}
+*/
+
+static void pgfault(int inum, uint32_t err)
+{
+	printf("~~~~ PAGE FAULT ~~~~\n");
+
+	printf("fault address: %x\n", get_fault_addr());
+
+	if(err & PG_PRESENT) {
+		if(err & 8) {
+			printf("reserved bit set in some paging structure\n");
+		} else {
+			printf("%s protection violation ", (err & PG_WRITABLE) ? "write" : "read");
+			printf("in %s mode\n", err & PG_USER ? "user" : "kernel");
+		}
+	} else {
+		printf("page not present\n");
+	}
+}
diff -r 2cbc2b922e49 -r 098b1cb5eeaa src/vm.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/vm.h	Sat Mar 26 21:39:14 2011 +0200
@@ -0,0 +1,42 @@
+#ifndef VM_H_
+#define VM_H_
+
+#include <stdlib.h>
+#include "mboot.h"
+
+/* page mapping flags */
+#define PG_PRESENT			(1 << 0)
+#define PG_WRITABLE			(1 << 1)
+#define PG_USER				(1 << 2)
+#define PG_WRITE_THROUGH	(1 << 3)
+#define PG_NOCACHE			(1 << 4)
+#define PG_ACCESSED			(1 << 5)
+#define PG_DIRTY			(1 << 6)
+#define PG_TYPE				(1 << 7)
+/* PG_GLOBAL mappings won't flush from TLB */
+#define PG_GLOBAL			(1 << 8)
+
+
+#define PGSIZE					4096
+#define PGOFFS_MASK				0xfff
+#define PGNUM_MASK				0xfffff000
+
+#define ADDR_TO_PAGE(x)		((uint32_t)(x) >> 12)
+#define PAGE_TO_ADDR(x)		((uint32_t)(x) << 12)
+
+#define ADDR_TO_PGTBL(x)		((uint32_t)(x) >> 22)
+#define ADDR_TO_PGTBL_PG(x)		(((uint32_t)(x) >> 12) & 0x3ff)
+#define ADDR_TO_PGOFFS(x)		((uint32_t)(x) & PGOFFS_MASK)
+
+#define PAGE_TO_PGTBL(x)		((uint32_t)(x) >> 10)
+#define PAGE_TO_PGTBL_PG(x)		((uint32_t)(x) & 0x3ff)
+
+
+void init_vm(struct mboot_info *mb);
+
+void map_page(int vpage, int ppage, unsigned int attr);
+void map_page_range(int vpg_start, int pgcount, int ppg_start, unsigned int attr);
+
+void map_mem_range(uint32_t vaddr, size_t sz, uint32_t paddr, unsigned int attr);
+
+#endif	/* VM_H_ */