/* Contains macros and constants for the kernel VM mapping, page tables,
 * segmentation, control registers, etc. */

#ifndef ROS_INC_ARCH_MMU_H
#define ROS_INC_ARCH_MMU_H

#ifdef __x86_64__
#include <ros/arch/mmu64.h>
#else
#include <ros/arch/mmu32.h>
#endif

/* **************************************** */
/* Control Registers */

// Control Register flags
#define CR0_PE		0x00000001	// Protection Enable
#define CR0_MP		0x00000002	// Monitor coProcessor
#define CR0_EM		0x00000004	// Emulation
#define CR0_TS		0x00000008	// Task Switched
#define CR0_ET		0x00000010	// Extension Type
#define CR0_NE		0x00000020	// Numeric Error
#define CR0_WP		0x00010000	// Write Protect
#define CR0_AM		0x00040000	// Alignment Mask
#define CR0_NW		0x20000000	// Not Writethrough - more tricky than it sounds
#define CR0_CD		0x40000000	// Cache Disable
#define CR0_PG		0x80000000	// Paging

// These two relate to the cacheability (L1, etc) of the page directory
#define CR3_PWT		0x00000008	// Page directory caching write through
#define CR3_PCD		0x00000010	// Page directory caching disabled

#define CR4_VME		0x00000001	// V86 Mode Extensions
#define CR4_PVI		0x00000002	// Protected-Mode Virtual Interrupts
#define CR4_TSD		0x00000004	// Time Stamp Disable
#define CR4_DE		0x00000008	// Debugging Extensions
#define CR4_PSE		0x00000010	// Page Size Extensions
#define CR4_PAE		0x00000020	// Physical Address Extensions
#define CR4_MCE		0x00000040	// Machine Check Enable
#define CR4_PGE		0x00000080	// Global Pages Enabled
#define CR4_PCE		0x00000100	// Performance counter enable
#define CR4_OSFXSR	0x00000200	// OS support for FXSAVE/FXRSTOR
#define CR4_OSXMME	0x00000400	// OS support for unmasked SIMD FP exceptions
#define CR4_VMXE	0x00002000	// VMX enable
#define CR4_SMXE	0x00004000	// SMX enable
#define CR4_OSXSAVE	0x00040000	// XSAVE and processor extended states-enabled

// Eflags register
#define FL_CF		0x00000001	// Carry Flag
#define FL_PF		0x00000004	// Parity Flag
#define FL_AF		0x00000010	// Auxiliary carry Flag
#define FL_ZF		0x00000040	// Zero Flag
#define FL_SF		0x00000080	// Sign Flag
#define FL_TF		0x00000100	// Trap Flag
#define FL_IF		0x00000200	// Interrupt Flag
#define FL_DF		0x00000400	// Direction Flag
#define FL_OF		0x00000800	// Overflow Flag
#define FL_IOPL_MASK	0x00003000	// I/O Privilege Level bitmask
#define FL_IOPL_0	0x00000000	//   IOPL == 0
#define FL_IOPL_1	0x00001000	//   IOPL == 1
#define FL_IOPL_2	0x00002000	//   IOPL == 2
#define FL_IOPL_3	0x00003000	//   IOPL == 3
#define FL_NT		0x00004000	// Nested Task
#define FL_RF		0x00010000	// Resume Flag
#define FL_VM		0x00020000	// Virtual 8086 mode
#define FL_AC		0x00040000	// Alignment Check
#define FL_VIF		0x00080000	// Virtual Interrupt Flag
#define FL_VIP		0x00100000	// Virtual Interrupt Pending
#define FL_ID		0x00200000	// ID flag

// Page fault error codes
#define FEC_PR		0x1	// Page fault caused by protection violation
#define FEC_WR		0x2	// Page fault caused by a write
#define FEC_U		0x4	// Page fault occured while in user mode

#endif /* ROS_INC_ARCH_MMU_H */