diff --git a/Makefile b/Makefile
index a5c2289..ccae37b 100644
--- a/Makefile
+++ b/Makefile
@@ -82,6 +82,12 @@ ifneq ($(NON_MATCHING),1)
 	@touch $@
 endif
 
+$(BUILD_DIR)/src/os/assert.marker: OPTFLAGS := -O0
+$(BUILD_DIR)/src/os/ackramromread.marker: OPTFLAGS := -O0
+$(BUILD_DIR)/src/os/ackramromwrite.marker: OPTFLAGS := -O0
+$(BUILD_DIR)/src/os/exit.marker: OPTFLAGS := -O0
+$(BUILD_DIR)/src/os/seterrorhandler.marker: OPTFLAGS := -O0
+
 $(BUILD_DIR)/%.marker: %.c
 	cd $(<D) && $(WORKING_DIR)/$(CC) $(CFLAGS) $(OPTFLAGS) -I $(WORKING_DIR)/include $(<F) -o $(WORKING_DIR)/$(@:.marker=.o)
 ifneq ($(NON_MATCHING),1)
diff --git a/include/PR/os.h b/include/PR/os.h
new file mode 100644
index 0000000..50d548f
--- /dev/null
+++ b/include/PR/os.h
@@ -0,0 +1,981 @@
+
+/**************************************************************************
+ *
+ *  $Revision: 1.149 $
+ *  $Date: 1997/12/15 04:30:52 $
+ *  $Source: /hosts/liberte/disk6/Master/cvsmdev2/PR/include/os.h,v $
+ *
+ **************************************************************************/
+
+
+#ifndef _OS_H_
+#define	_OS_H_
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+extern "C" {
+#endif
+
+#include "PR/ultratypes.h"
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+
+/**************************************************************************
+ *
+ * Type definitions
+ *
+ */
+
+typedef s32	OSPri;
+typedef s32	OSId;
+typedef union	{ struct { f32 f_odd; f32 f_even; } f; f64 d; }	__OSfp;
+
+typedef struct {
+	u64	at, v0, v1, a0, a1, a2, a3;
+	u64	t0, t1, t2, t3, t4, t5, t6, t7;
+	u64	s0, s1, s2, s3, s4, s5, s6, s7;
+	u64	t8, t9,         gp, sp, s8, ra;
+	u64	lo, hi;
+	u32	sr, pc, cause, badvaddr, rcp;
+	u32	fpcsr;
+	__OSfp	 fp0,  fp2,  fp4,  fp6,  fp8, fp10, fp12, fp14;
+	__OSfp	fp16, fp18, fp20, fp22, fp24, fp26, fp28, fp30;
+} __OSThreadContext;
+
+typedef struct OSThread_s {
+	struct OSThread_s	*next;		/* run/mesg queue link */
+	OSPri			priority;	/* run/mesg queue priority */
+	struct OSThread_s	**queue;	/* queue thread is on */
+	struct OSThread_s	*tlnext;	/* all threads queue link */
+	u16			state;		/* OS_STATE_* */
+	u16			flags;		/* flags for rmon */
+	OSId			id;		/* id for debugging */
+	int			fp;		/* thread has used fp unit */
+	__OSThreadContext	context;	/* register/interrupt mask */
+} OSThread;
+
+typedef u32 OSEvent;
+typedef u32 OSIntMask;
+typedef u32 OSPageMask;
+typedef u32 OSHWIntr;
+
+/*
+ * Structure for message
+ */
+typedef void *	OSMesg;
+
+/*
+ * Structure for message queue
+ */
+typedef struct OSMesgQueue_s {
+	OSThread	*mtqueue;	/* Queue to store threads blocked
+					   on empty mailboxes (receive) */
+	OSThread	*fullqueue;	/* Queue to store threads blocked
+					   on full mailboxes (send) */
+	s32		validCount;	/* Contains number of valid message */
+	s32		first;		/* Points to first valid message */
+	s32		msgCount;	/* Contains total # of messages */
+	OSMesg		*msg;		/* Points to message buffer array */
+} OSMesgQueue;
+
+/*
+ * Structure for Enhanced PI interface
+ */
+
+/*
+ * OSTranxInfo is set up for Leo Disk DMA. This info will be maintained
+ * by exception handler. This is how the PIMGR and the ISR communicate.
+ */
+
+typedef struct {
+	u32		errStatus;	/* error status */
+        void     	*dramAddr;      /* RDRAM buffer address (DMA) */
+	void		*C2Addr;	/* C2 buffer address */
+	u32		sectorSize;	/* size of transfering sector */
+	u32		C1ErrNum;	/* total # of C1 errors */
+	u32		C1ErrSector[4];	/* error sectors */
+} __OSBlockInfo;
+
+typedef struct {
+	u32     	cmdType;       	/* for disk only */
+	u16     	transferMode;   /* Block, Track, or sector?   */
+	u16		blockNum;	/* which block is transfering */
+	s32     	sectorNum;      /* which sector is transfering */
+	u32     	devAddr;        /* Device buffer address */
+	u32		bmCtlShadow;	/* asic bm_ctl(510) register shadow ram */
+	u32		seqCtlShadow;	/* asic seq_ctl(518) register shadow ram */
+	__OSBlockInfo	block[2];	/* bolck transfer info */
+} __OSTranxInfo;
+
+
+typedef struct OSPiHandle_s {
+        struct OSPiHandle_s     *next;  /* point to next handle on the table */
+        u8                      type;   /* DEVICE_TYPE_BULK for disk */
+        u8                      latency;        /* domain latency */
+        u8                      pageSize;       /* domain page size */
+        u8                      relDuration;    /* domain release duration */
+        u8                      pulse;          /* domain pulse width */
+	u8			domain;		/* which domain */
+        u32                     baseAddress;    /* Domain address */
+        u32                     speed;          /* for roms only */
+        /* The following are "private" elements" */
+        __OSTranxInfo           transferInfo;	/* for disk only */
+} OSPiHandle;
+
+typedef struct {
+        u8      type;
+        u32     address;
+} OSPiInfo;
+
+/*
+ * Structure for I/O message block
+ */
+typedef struct {
+        u16 		type;		/* Message type */
+        u8 		pri;		/* Message priority (High or Normal) */
+        u8		status;		/* Return status */
+	OSMesgQueue	*retQueue;	/* Return message queue to notify I/O 
+					 * completion */
+} OSIoMesgHdr;
+
+typedef struct {
+	OSIoMesgHdr	hdr;		/* Message header */
+	void *		dramAddr;	/* RDRAM buffer address (DMA) */
+	u32		devAddr;	/* Device buffer address (DMA) */
+	u32 		size;		/* DMA transfer size in bytes */
+	OSPiHandle	*piHandle;	/* PI device handle */
+} OSIoMesg;
+
+/*
+ * Structure for device manager block
+ */
+typedef struct {
+        s32             active;		/* Status flag */
+	OSThread	*thread;	/* Calling thread */
+        OSMesgQueue  	*cmdQueue;	/* Command queue */
+        OSMesgQueue  	*evtQueue;	/* Event queue */
+        OSMesgQueue  	*acsQueue;	/* Access queue */
+					/* Raw DMA routine */
+        s32             (*dma)(s32, u32, void *, u32);
+        s32             (*edma)(OSPiHandle *, s32, u32, void *, u32);
+} OSDevMgr;
+
+
+/*
+ * Structure to store VI register values that remain the same between 2 fields
+ */
+typedef struct {
+    u32	ctrl;
+    u32	width;
+    u32	burst;
+    u32	vSync;
+    u32	hSync;
+    u32	leap;
+    u32	hStart;
+    u32	xScale;
+    u32	vCurrent;
+} OSViCommonRegs;
+
+
+/*
+ * Structure to store VI register values that change between fields
+ */
+typedef struct {
+    u32	origin;
+    u32	yScale;
+    u32	vStart;	
+    u32	vBurst;
+    u32	vIntr;
+} OSViFieldRegs;
+
+
+/*
+ * Structure for VI mode
+ */
+typedef struct {
+    u8			type;		/* Mode type */
+    OSViCommonRegs	comRegs;	/* Common registers for both fields */
+    OSViFieldRegs	fldRegs[2];	/* Registers for Field 1  & 2 */
+} OSViMode;
+
+/*
+ * Structure for time value 
+ */
+typedef u64	OSTime;
+
+/*
+ * Structure for interval timer
+ */
+typedef struct OSTimer_s {
+	struct OSTimer_s	*next;	/* point to next timer in list */
+	struct OSTimer_s	*prev;	/* point to previous timer in list */
+	OSTime			interval;	/* duration set by user */
+	OSTime			value;		/* time remaining before */
+						/* timer fires           */
+	OSMesgQueue		*mq;		/* Message Queue */
+	OSMesg			msg;		/* Message to send */
+} OSTimer;
+
+/*
+ * Structure for controllers 
+ */
+
+typedef struct {
+	u16     type;                   /* Controller Type */
+	u8      status;                 /* Controller status */
+	u8	errno;
+}OSContStatus;
+
+typedef struct {
+	u16     button;
+	s8      stick_x;		/* -80 <= stick_x <= 80 */
+	s8      stick_y;		/* -80 <= stick_y <= 80 */
+	u8	errno;
+} OSContPad;
+
+typedef struct {
+	void    *address;               /* Ram pad Address:  11 bits */
+	u8      databuffer[32];         /* address of the data buffer */
+        u8      addressCrc;             /* CRC code for address */
+	u8      dataCrc;                /* CRC code for data */
+	u8	errno;
+} OSContRamIo;
+
+/*
+ * Structure for file system
+ */
+
+
+
+typedef struct {
+	int		status;
+	OSMesgQueue 	*queue;
+	int		channel;
+	u8		id[32];
+	u8		label[32];
+	int		version;
+	int		dir_size;
+	int		inode_table;		/* block location */
+	int		minode_table;		/* mirrioring inode_table */
+	int		dir_table;		/* block location */
+	int		inode_start_page;	/* page # */
+	u8		banks;
+	u8		activebank;
+} OSPfs;
+
+
+typedef struct {
+	u32	file_size;	/* bytes */
+  	u32 	game_code;
+  	u16 	company_code;
+  	char  	ext_name[4];
+  	char 	game_name[16];
+} OSPfsState;
+	
+/*
+ * Structure for Profiler 
+ */
+typedef struct {
+	u16	*histo_base;		/* histogram base */
+	u32	histo_size;		/* histogram size */
+	u32	*text_start;		/* start of text segment */
+	u32	*text_end;		/* end of text segment */
+} OSProf;
+
+#endif /* defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS) */
+
+/**************************************************************************
+ *
+ * Global definitions
+ *
+ */
+
+/* Thread states */
+
+#define OS_STATE_STOPPED	1
+#define OS_STATE_RUNNABLE	2
+#define OS_STATE_RUNNING	4
+#define OS_STATE_WAITING	8
+
+/* Events */
+#ifdef _FINALROM
+#define OS_NUM_EVENTS           15
+#else
+#define OS_NUM_EVENTS           23
+#endif
+
+#define OS_EVENT_SW1              0     /* CPU SW1 interrupt */
+#define OS_EVENT_SW2              1     /* CPU SW2 interrupt */
+#define OS_EVENT_CART             2     /* Cartridge interrupt: used by rmon */
+#define OS_EVENT_COUNTER          3     /* Counter int: used by VI/Timer Mgr */
+#define OS_EVENT_SP               4     /* SP task done interrupt */
+#define OS_EVENT_SI               5     /* SI (controller) interrupt */
+#define OS_EVENT_AI               6     /* AI interrupt */
+#define OS_EVENT_VI               7     /* VI interrupt: used by VI/Timer Mgr */
+#define OS_EVENT_PI               8     /* PI interrupt: used by PI Manager */
+#define OS_EVENT_DP               9     /* DP full sync interrupt */
+#define OS_EVENT_CPU_BREAK        10    /* CPU breakpoint: used by rmon */
+#define OS_EVENT_SP_BREAK         11    /* SP breakpoint:  used by rmon */
+#define OS_EVENT_FAULT            12    /* CPU fault event: used by rmon */
+#define OS_EVENT_THREADSTATUS     13    /* CPU thread status: used by rmon */
+#define OS_EVENT_PRENMI           14    /* Pre NMI interrupt */
+#ifndef _FINALROM
+#define OS_EVENT_RDB_READ_DONE    15    /* RDB read ok event: used by rmon */
+#define OS_EVENT_RDB_LOG_DONE     16    /* read of log data complete */
+#define OS_EVENT_RDB_DATA_DONE    17    /* read of hostio data complete */
+#define OS_EVENT_RDB_REQ_RAMROM   18    /* host needs ramrom access */
+#define OS_EVENT_RDB_FREE_RAMROM  19    /* host is done with ramrom access */
+#define OS_EVENT_RDB_DBG_DONE     20
+#define OS_EVENT_RDB_FLUSH_PROF   21
+#define OS_EVENT_RDB_ACK_PROF     22
+#endif
+
+/* Flags for debugging purpose */
+
+#define	OS_FLAG_CPU_BREAK	1	/* Break exception has occurred */
+#define	OS_FLAG_FAULT		2	/* CPU fault has occurred */
+
+/* Interrupt masks */
+
+#define	OS_IM_NONE	0x00000001
+#define OS_IM_RCP	0x00000401
+#define	OS_IM_SW1	0x00000501
+#define	OS_IM_SW2	0x00000601
+#define	OS_IM_CART	0x00000c01
+#define	OS_IM_PRENMI	0x00001401
+#define OS_IM_RDBWRITE	0x00002401
+#define OS_IM_RDBREAD	0x00004401
+#define	OS_IM_COUNTER	0x00008401
+#define	OS_IM_CPU	0x0000ff01
+#define	OS_IM_SP	0x00010401
+#define	OS_IM_SI	0x00020401
+#define	OS_IM_AI	0x00040401
+#define	OS_IM_VI	0x00080401
+#define	OS_IM_PI	0x00100401
+#define	OS_IM_DP	0x00200401
+#define	OS_IM_ALL	0x003fff01
+#define	RCP_IMASK	0x003f0000
+#define	RCP_IMASKSHIFT	16
+
+/* Recommended thread priorities for the system threads */
+
+#define OS_PRIORITY_MAX		255
+#define OS_PRIORITY_VIMGR	254
+#define OS_PRIORITY_RMON	250
+#define OS_PRIORITY_RMONSPIN	200
+#define OS_PRIORITY_PIMGR	150
+#define OS_PRIORITY_SIMGR	140
+#define	OS_PRIORITY_APPMAX	127
+#define OS_PRIORITY_IDLE	  0	/* Must be 0 */
+
+
+/* Flags to turn blocking on/off when sending/receiving message */
+
+#define	OS_MESG_NOBLOCK		0
+#define	OS_MESG_BLOCK		1
+
+/* Flags to indicate direction of data transfer */
+
+#define	OS_READ			0		/* device -> RDRAM */
+#define	OS_WRITE		1		/* device <- RDRAM */
+#define	OS_OTHERS		2		/* for Leo disk only */
+
+/*
+ * I/O message types
+ */
+#define OS_MESG_TYPE_BASE	(10)
+#define OS_MESG_TYPE_LOOPBACK	(OS_MESG_TYPE_BASE+0)
+#define OS_MESG_TYPE_DMAREAD	(OS_MESG_TYPE_BASE+1)
+#define OS_MESG_TYPE_DMAWRITE	(OS_MESG_TYPE_BASE+2)
+#define OS_MESG_TYPE_VRETRACE	(OS_MESG_TYPE_BASE+3)
+#define OS_MESG_TYPE_COUNTER	(OS_MESG_TYPE_BASE+4)
+#define OS_MESG_TYPE_EDMAREAD	(OS_MESG_TYPE_BASE+5)
+#define OS_MESG_TYPE_EDMAWRITE	(OS_MESG_TYPE_BASE+6)
+
+/*
+ * I/O message priority
+ */
+#define OS_MESG_PRI_NORMAL	0
+#define OS_MESG_PRI_HIGH	1
+
+/*
+ * Page size argument for TLB routines
+ */
+#define OS_PM_4K	0x0000000
+#define OS_PM_16K	0x0006000
+#define OS_PM_64K	0x001e000
+#define OS_PM_256K	0x007e000
+#define OS_PM_1M	0x01fe000
+#define OS_PM_4M	0x07fe000
+#define OS_PM_16M	0x1ffe000
+
+/*
+ * Stack size for I/O device managers: PIM (PI Manager), VIM (VI Manager),
+ *	SIM (SI Manager)
+ *
+ */
+#define OS_PIM_STACKSIZE	4096
+#define OS_VIM_STACKSIZE	4096
+#define OS_SIM_STACKSIZE	4096
+
+#define	OS_MIN_STACKSIZE	72
+
+/*
+ * Values for osTvType 
+ */
+#define	OS_TV_PAL		0
+#define	OS_TV_NTSC		1
+#define	OS_TV_MPAL		2
+
+/*
+ * Video Interface (VI) mode type
+ */
+#define OS_VI_NTSC_LPN1		0	/* NTSC */
+#define OS_VI_NTSC_LPF1		1
+#define OS_VI_NTSC_LAN1		2
+#define OS_VI_NTSC_LAF1		3
+#define OS_VI_NTSC_LPN2		4
+#define OS_VI_NTSC_LPF2		5
+#define OS_VI_NTSC_LAN2		6
+#define OS_VI_NTSC_LAF2		7
+#define OS_VI_NTSC_HPN1		8
+#define OS_VI_NTSC_HPF1		9
+#define OS_VI_NTSC_HAN1		10
+#define OS_VI_NTSC_HAF1		11
+#define OS_VI_NTSC_HPN2		12
+#define OS_VI_NTSC_HPF2		13
+
+#define OS_VI_PAL_LPN1		14	/* PAL */
+#define OS_VI_PAL_LPF1		15
+#define OS_VI_PAL_LAN1		16
+#define OS_VI_PAL_LAF1		17
+#define OS_VI_PAL_LPN2		18
+#define OS_VI_PAL_LPF2		19
+#define OS_VI_PAL_LAN2		20
+#define OS_VI_PAL_LAF2		21
+#define OS_VI_PAL_HPN1		22
+#define OS_VI_PAL_HPF1		23
+#define OS_VI_PAL_HAN1		24
+#define OS_VI_PAL_HAF1		25
+#define OS_VI_PAL_HPN2		26
+#define OS_VI_PAL_HPF2		27
+
+#define OS_VI_MPAL_LPN1		28	/* MPAL - mainly Brazil */
+#define OS_VI_MPAL_LPF1		29
+#define OS_VI_MPAL_LAN1		30
+#define OS_VI_MPAL_LAF1		31
+#define OS_VI_MPAL_LPN2		32
+#define OS_VI_MPAL_LPF2		33
+#define OS_VI_MPAL_LAN2		34
+#define OS_VI_MPAL_LAF2		35
+#define OS_VI_MPAL_HPN1		36
+#define OS_VI_MPAL_HPF1		37
+#define OS_VI_MPAL_HAN1		38
+#define OS_VI_MPAL_HAF1		39
+#define OS_VI_MPAL_HPN2		40
+#define OS_VI_MPAL_HPF2		41
+
+/*
+ * Video Interface (VI) special features
+ */
+#define	OS_VI_GAMMA_ON			0x0001
+#define	OS_VI_GAMMA_OFF			0x0002
+#define	OS_VI_GAMMA_DITHER_ON		0x0004
+#define	OS_VI_GAMMA_DITHER_OFF		0x0008
+#define	OS_VI_DIVOT_ON			0x0010
+#define	OS_VI_DIVOT_OFF			0x0020
+#define	OS_VI_DITHER_FILTER_ON		0x0040
+#define	OS_VI_DITHER_FILTER_OFF		0x0080
+
+/*
+ * Video Interface (VI) mode attribute bit
+ */
+#define OS_VI_BIT_NONINTERLACE		0x0001          /* lo-res */
+#define OS_VI_BIT_INTERLACE		0x0002          /* lo-res */
+#define OS_VI_BIT_NORMALINTERLACE	0x0004          /* hi-res */
+#define OS_VI_BIT_DEFLICKINTERLACE	0x0008          /* hi-res */
+#define OS_VI_BIT_ANTIALIAS		0x0010
+#define OS_VI_BIT_POINTSAMPLE		0x0020
+#define OS_VI_BIT_16PIXEL		0x0040
+#define OS_VI_BIT_32PIXEL		0x0080
+#define OS_VI_BIT_LORES			0x0100
+#define OS_VI_BIT_HIRES			0x0200
+#define OS_VI_BIT_NTSC			0x0400
+#define OS_VI_BIT_PAL			0x0800
+
+/* 
+ * Leo Disk 
+ */
+
+/* transfer mode */
+
+#define LEO_BLOCK_MODE	1
+#define LEO_TRACK_MODE	2
+#define LEO_SECTOR_MODE	3
+
+/*
+ *  Controllers  number
+ */
+
+#ifndef _HW_VERSION_1
+#define MAXCONTROLLERS  4
+#else
+#define MAXCONTROLLERS  6
+#endif
+
+/* controller errors */
+#define CONT_NO_RESPONSE_ERROR          0x8
+#define CONT_OVERRUN_ERROR              0x4
+#ifdef _HW_VERSION_1
+#define CONT_FRAME_ERROR                0x2
+#define CONT_COLLISION_ERROR            0x1
+#endif 
+
+/* Controller type */
+
+#define CONT_ABSOLUTE           0x0001
+#define CONT_RELATIVE           0x0002
+#define CONT_JOYPORT            0x0004
+#define CONT_EEPROM		0x8000
+#define CONT_EEP16K		0x4000
+#define	CONT_TYPE_MASK		0x1f07
+#define	CONT_TYPE_NORMAL	0x0005
+#define	CONT_TYPE_MOUSE		0x0002
+
+/* Controller status */
+
+#define CONT_CARD_ON            0x01
+#define CONT_CARD_PULL          0x02
+#define CONT_ADDR_CRC_ER        0x04
+#define CONT_EEPROM_BUSY	0x80
+
+/* EEPROM TYPE */
+
+#define EEPROM_TYPE_4K		0x01
+#define EEPROM_TYPE_16K		0x02
+
+/* Buttons */
+
+#define CONT_A      0x8000
+#define CONT_B      0x4000
+#define CONT_G	    0x2000
+#define CONT_START  0x1000
+#define CONT_UP     0x0800
+#define CONT_DOWN   0x0400
+#define CONT_LEFT   0x0200
+#define CONT_RIGHT  0x0100
+#define CONT_L      0x0020
+#define CONT_R      0x0010
+#define CONT_E      0x0008
+#define CONT_D      0x0004
+#define CONT_C      0x0002
+#define CONT_F      0x0001
+
+/* Nintendo's official button names */
+
+#define A_BUTTON	CONT_A
+#define B_BUTTON	CONT_B
+#define L_TRIG		CONT_L
+#define R_TRIG		CONT_R
+#define Z_TRIG		CONT_G
+#define START_BUTTON	CONT_START
+#define U_JPAD		CONT_UP
+#define L_JPAD		CONT_LEFT
+#define R_JPAD		CONT_RIGHT
+#define D_JPAD		CONT_DOWN
+#define U_CBUTTONS	CONT_E
+#define L_CBUTTONS	CONT_C
+#define R_CBUTTONS	CONT_F
+#define D_CBUTTONS	CONT_D
+
+/* File System size */
+#define	OS_PFS_VERSION		0x0200
+#define	OS_PFS_VERSION_HI	(OS_PFS_VERSION >> 8)
+#define	OS_PFS_VERSION_LO	(OS_PFS_VERSION & 255)
+
+#define PFS_FILE_NAME_LEN       16
+#define PFS_FILE_EXT_LEN        4
+#define BLOCKSIZE		32		/* bytes */
+#define PFS_ONE_PAGE            8		/* blocks */
+#define PFS_MAX_BANKS		62
+
+/* File System flag */
+
+#define PFS_READ                0
+#define PFS_WRITE               1
+#define PFS_CREATE              2
+
+/* File System status */
+#define PFS_INITIALIZED		0x1
+#define PFS_CORRUPTED		0x2		/* File system was corrupted */
+
+/* File System error number */
+
+#define PFS_ERR_NOPACK		1	/* no memory card is plugged or   */
+#define PFS_ERR_NEW_PACK        2	/* ram pack has been changed to a */
+					/* different one 		  */
+#define PFS_ERR_INCONSISTENT    3	/* need to run Pfschecker 	  */
+#define PFS_ERR_CONTRFAIL	CONT_OVERRUN_ERROR              
+#define PFS_ERR_INVALID         5	/* invalid parameter or file not exist*/
+#define PFS_ERR_BAD_DATA        6       /* the data read from pack are bad*/
+#define PFS_DATA_FULL           7	/* no free pages on ram pack      */
+#define PFS_DIR_FULL            8	/* no free directories on ram pack*/
+#define PFS_ERR_EXIST		9	/* file exists 			  */
+#define PFS_ERR_ID_FATAL	10	/* dead ram pack */
+#define PFS_ERR_DEVICE		11	/* wrong device type*/
+
+/* definition for EEPROM */
+
+#define EEPROM_MAXBLOCKS	64
+#define EEP16K_MAXBLOCKS	256
+#define EEPROM_BLOCK_SIZE	8
+
+/*
+ * PI/EPI
+ */
+#define PI_DOMAIN1      0
+#define PI_DOMAIN2      1
+
+/*
+ * Profiler constants
+ */
+#define PROF_MIN_INTERVAL	50	/* microseconds */
+
+/*
+ * Boot addresses
+ */
+#define	BOOT_ADDRESS_ULTRA	0x80000400
+#define	BOOT_ADDRESS_COSIM	0x80002000
+#define	BOOT_ADDRESS_EMU	0x20010000
+#define	BOOT_ADDRESS_INDY 	0x88100000
+
+/*
+ * Size of buffer the retains contents after NMI
+ */
+#define OS_APP_NMI_BUFSIZE	64
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+
+/**************************************************************************
+ *
+ * Macro definitions
+ *
+ */
+
+/* PARTNER-N64 */
+#ifdef PTN64
+#define osReadHost osReadHost_pt
+#define osWriteHost osWriteHost_pt
+#endif
+
+/* Get count of valid messages in queue */
+#define MQ_GET_COUNT(mq)        ((mq)->validCount)
+
+/* Figure out if message queue is empty or full */
+#define MQ_IS_EMPTY(mq)		(MQ_GET_COUNT(mq) == 0)
+#define MQ_IS_FULL(mq)		(MQ_GET_COUNT(mq) >= (mq)->msgCount)
+
+/*
+ * CPU counter increments at 3/4 of bus clock rate:
+ *
+ * Bus Clock	Proc Clock	Counter (1/2 Proc Clock)
+ * ---------	----------	------------------------
+ * 62.5 Mhz	93.75 Mhz	46.875 Mhz
+ */
+extern u64 osClockRate;
+
+#define	OS_CLOCK_RATE		62500000LL
+#define	OS_CPU_COUNTER		(OS_CLOCK_RATE*3/4)
+#define OS_NSEC_TO_CYCLES(n)	(((u64)(n)*(OS_CPU_COUNTER/15625000LL))/(1000000000LL/15625000LL))
+#define OS_USEC_TO_CYCLES(n)	(((u64)(n)*(OS_CPU_COUNTER/15625LL))/(1000000LL/15625LL))
+#define OS_CYCLES_TO_NSEC(c)	(((u64)(c)*(1000000000LL/15625000LL))/(OS_CPU_COUNTER/15625000LL))
+#define OS_CYCLES_TO_USEC(c)	(((u64)(c)*(1000000LL/15625LL))/(OS_CPU_COUNTER/15625LL))
+
+/**************************************************************************
+ *
+ * Extern variables
+ *
+ */
+extern OSViMode	osViModeTable[];	/* Global VI mode table */
+
+extern OSViMode	osViModeNtscLpn1;	/* Individual VI NTSC modes */
+extern OSViMode	osViModeNtscLpf1;
+extern OSViMode	osViModeNtscLan1;
+extern OSViMode	osViModeNtscLaf1;
+extern OSViMode	osViModeNtscLpn2;
+extern OSViMode	osViModeNtscLpf2;
+extern OSViMode	osViModeNtscLan2;
+extern OSViMode	osViModeNtscLaf2;
+extern OSViMode	osViModeNtscHpn1;
+extern OSViMode	osViModeNtscHpf1;
+extern OSViMode	osViModeNtscHan1;
+extern OSViMode	osViModeNtscHaf1;
+extern OSViMode	osViModeNtscHpn2;
+extern OSViMode	osViModeNtscHpf2;
+
+extern OSViMode	osViModePalLpn1;	/* Individual VI PAL modes */
+extern OSViMode	osViModePalLpf1;
+extern OSViMode	osViModePalLan1;
+extern OSViMode	osViModePalLaf1;
+extern OSViMode	osViModePalLpn2;
+extern OSViMode	osViModePalLpf2;
+extern OSViMode	osViModePalLan2;
+extern OSViMode	osViModePalLaf2;
+extern OSViMode	osViModePalHpn1;
+extern OSViMode	osViModePalHpf1;
+extern OSViMode	osViModePalHan1;
+extern OSViMode	osViModePalHaf1;
+extern OSViMode	osViModePalHpn2;
+extern OSViMode	osViModePalHpf2;
+
+extern OSViMode	osViModeMpalLpn1;	/* Individual VI MPAL modes */
+extern OSViMode	osViModeMpalLpf1;
+extern OSViMode	osViModeMpalLan1;
+extern OSViMode	osViModeMpalLaf1;
+extern OSViMode	osViModeMpalLpn2;
+extern OSViMode	osViModeMpalLpf2;
+extern OSViMode	osViModeMpalLan2;
+extern OSViMode	osViModeMpalLaf2;
+extern OSViMode	osViModeMpalHpn1;
+extern OSViMode	osViModeMpalHpf1;
+extern OSViMode	osViModeMpalHan1;
+extern OSViMode	osViModeMpalHaf1;
+extern OSViMode	osViModeMpalHpn2;
+extern OSViMode	osViModeMpalHpf2;
+
+extern s32 	osRomType;	/* Bulk or cartridge ROM. 0=cartridge 1=bulk */
+extern void 	*osRomBase;	/* Rom base address of the game image */
+extern s32 	osTvType;	/* 0 = PAL, 1 = NTSC, 2 = MPAL */
+extern s32 	osResetType;	/* 0 = cold reset, 1 = NMI */
+extern s32 	osCicId;
+extern s32 	osVersion;
+extern u32	osMemSize;	/* Memory Size */
+extern s32	osAppNMIBuffer[];
+
+extern OSIntMask __OSGlobalIntMask;	/* global interrupt mask */
+extern OSPiHandle      *__osPiTable;    /* The head of OSPiHandle link list */
+extern OSPiHandle      *__osDiskHandle; /* For exceptasm to get disk info*/
+
+
+
+/**************************************************************************
+ *
+ * Function prototypes
+ *
+ */
+
+/* Thread operations */
+
+extern void		osCreateThread(OSThread *, OSId, void (*)(void *),
+				       void *, void *, OSPri);
+extern void		osDestroyThread(OSThread *);
+extern void		osYieldThread(void);
+extern void		osStartThread(OSThread *);
+extern void		osStopThread(OSThread *);
+extern OSId		osGetThreadId(OSThread *);
+extern void		osSetThreadPri(OSThread *, OSPri);
+extern OSPri		osGetThreadPri(OSThread *);
+
+/* Message operations */
+
+extern void		osCreateMesgQueue(OSMesgQueue *, OSMesg *, s32);
+extern s32		osSendMesg(OSMesgQueue *, OSMesg, s32);
+extern s32		osJamMesg(OSMesgQueue *, OSMesg, s32);
+extern s32		osRecvMesg(OSMesgQueue *, OSMesg *, s32);
+
+/* Event operations */
+
+extern void		osSetEventMesg(OSEvent, OSMesgQueue *, OSMesg);
+
+/* Interrupt operations */
+
+extern OSIntMask	osGetIntMask(void);
+extern OSIntMask	osSetIntMask(OSIntMask);
+
+/* RDB port operations */
+
+extern void             osInitRdb(u8 *sendBuf, u32 sendSize);
+
+/* Cache operations and macros */
+
+extern void		osInvalDCache(void *, s32);
+extern void		osInvalICache(void *, s32);
+extern void		osWritebackDCache(void *, s32);
+extern void		osWritebackDCacheAll(void);
+
+#define	OS_DCACHE_ROUNDUP_ADDR(x)	(void *)(((((u32)(x)+0xf)/0x10)*0x10))
+#define	OS_DCACHE_ROUNDUP_SIZE(x)	(u32)(((((u32)(x)+0xf)/0x10)*0x10))
+
+/* TLB management routines */
+
+extern void		osMapTLB(s32, OSPageMask, void *, u32, u32, s32);
+extern void		osMapTLBRdb(void);
+extern void		osUnmapTLB(s32);
+extern void		osUnmapTLBAll(void);
+extern void		osSetTLBASID(s32);
+
+/* Address translation routines and macros */
+
+extern u32		 osVirtualToPhysical(void *);
+extern void *		 osPhysicalToVirtual(u32);
+
+#define	OS_K0_TO_PHYSICAL(x)	(u32)(((char *)(x)-0x80000000))
+#define	OS_K1_TO_PHYSICAL(x)	(u32)(((char *)(x)-0xa0000000))
+
+#define	OS_PHYSICAL_TO_K0(x)	(void *)(((u32)(x)+0x80000000))
+#define	OS_PHYSICAL_TO_K1(x)	(void *)(((u32)(x)+0xa0000000))
+
+/* I/O operations */
+
+/* Audio interface (Ai) */
+extern u32 		osAiGetStatus(void);
+extern u32 		osAiGetLength(void);
+extern s32		osAiSetFrequency(u32);
+extern s32		osAiSetNextBuffer(void *, u32);
+
+/* Display processor interface (Dp) */
+extern u32 		osDpGetStatus(void);
+extern void		osDpSetStatus(u32);
+extern void 		osDpGetCounters(u32 *);
+extern s32		osDpSetNextBuffer(void *, u64);
+
+/* Peripheral interface (Pi) */
+extern u32 		osPiGetStatus(void);
+extern s32		osPiGetDeviceType(void);
+extern s32		osPiRawWriteIo(u32, u32);
+extern s32		osPiRawReadIo(u32, u32 *);
+extern s32		osPiRawStartDma(s32, u32, void *, u32);
+extern s32		osPiWriteIo(u32, u32);
+extern s32		osPiReadIo(u32, u32 *);
+extern s32		osPiStartDma(OSIoMesg *, s32, s32, u32, void *, u32,
+				     OSMesgQueue *);
+extern void		osCreatePiManager(OSPri, OSMesgQueue *, OSMesg *, s32);
+
+/* Video interface (Vi) */
+extern u32		osViGetStatus(void);
+extern u32		osViGetCurrentMode(void);
+extern u32		osViGetCurrentLine(void);
+extern u32		osViGetCurrentField(void);
+extern void		*osViGetCurrentFramebuffer(void);
+extern void		*osViGetNextFramebuffer(void);
+extern void		osViSetXScale(f32);
+extern void		osViSetYScale(f32);
+extern void		osViSetSpecialFeatures(u32);
+extern void		osViSetMode(OSViMode *);
+extern void		osViSetEvent(OSMesgQueue *, OSMesg, u32);
+extern void		osViSwapBuffer(void *);
+extern void		osViBlack(u8);
+extern void		osViFade(u8, u16);
+extern void		osViRepeatLine(u8);
+extern void		osCreateViManager(OSPri);
+
+/* Timer interface */
+
+extern OSTime		osGetTime(void);
+extern void		osSetTime(OSTime);
+extern int		osSetTimer(OSTimer *, OSTime, OSTime,
+				   OSMesgQueue *, OSMesg);
+extern int		osStopTimer(OSTimer *);
+
+/* Controller interface */
+
+extern s32		osContInit(OSMesgQueue *, u8 *, OSContStatus *);
+extern s32		osContReset(OSMesgQueue *, OSContStatus *);
+extern s32		osContStartQuery(OSMesgQueue *);
+extern s32		osContStartReadData(OSMesgQueue *);
+#ifndef _HW_VERSION_1
+extern s32		osContSetCh(u8);
+#endif
+extern void		osContGetQuery(OSContStatus *);
+extern void		osContGetReadData(OSContPad *);
+
+/* file system interface */
+
+extern s32 osPfsInitPak(OSMesgQueue *, OSPfs *, int);
+extern s32 osPfsRepairId(OSPfs *);
+extern s32 osPfsInit(OSMesgQueue *, OSPfs *, int);
+extern s32 osPfsReFormat(OSPfs *, OSMesgQueue *, int);
+extern s32 osPfsChecker(OSPfs *);
+extern s32 osPfsAllocateFile(OSPfs *, u16, u32, u8 *, u8 *, int, s32 *);
+extern s32 osPfsFindFile(OSPfs *, u16, u32, u8 *, u8 *, s32 *);
+extern s32 osPfsDeleteFile(OSPfs *, u16, u32, u8 *, u8 *);
+extern s32 osPfsReadWriteFile(OSPfs *, s32, u8, int, int, u8 *);
+extern s32 osPfsFileState(OSPfs *, s32, OSPfsState *);
+extern s32 osPfsGetLabel(OSPfs *, u8 *, int *);
+extern s32 osPfsSetLabel(OSPfs *, u8 *);
+extern s32 osPfsIsPlug(OSMesgQueue *, u8 *);
+extern s32 osPfsFreeBlocks(OSPfs *, s32 *);
+extern s32 osPfsNumFiles(OSPfs *, s32 *, s32 *);
+
+/* EEPROM interface */
+
+extern s32 osEepromProbe(OSMesgQueue *);
+extern s32 osEepromRead(OSMesgQueue *, u8, u8 *);
+extern s32 osEepromWrite(OSMesgQueue *, u8, u8 *);
+extern s32 osEepromLongRead(OSMesgQueue *, u8, u8 *, int);
+extern s32 osEepromLongWrite(OSMesgQueue *, u8, u8 *, int);
+
+/* MOTOR interface */
+
+extern s32 osMotorInit(OSMesgQueue *, OSPfs *, int);
+extern s32 osMotorStop(OSPfs *);
+extern s32 osMotorStart(OSPfs *);
+
+/* Enhanced PI interface */
+
+extern OSPiHandle *osCartRomInit(void);
+extern OSPiHandle *osLeoDiskInit(void);
+extern OSPiHandle *osDriveRomInit(void);
+
+extern s32 osEPiDeviceType(OSPiHandle *, OSPiInfo *);
+extern s32 osEPiRawWriteIo(OSPiHandle *, u32 , u32);
+extern s32 osEPiRawReadIo(OSPiHandle *, u32 , u32 *);
+extern s32 osEPiRawStartDma(OSPiHandle *, s32 , u32 , void *, u32 );
+extern s32 osEPiWriteIo(OSPiHandle *, u32 , u32 );
+extern s32 osEPiReadIo(OSPiHandle *, u32 , u32 *);
+extern s32 osEPiStartDma(OSPiHandle *, OSIoMesg *, s32);
+extern s32 osEPiLinkHandle(OSPiHandle *);
+
+/* Profiler Interface */
+
+extern void		osProfileInit(OSProf *, u32 profcnt);
+extern void		osProfileStart(u32);
+extern void		osProfileFlush(void);
+extern void		osProfileStop(void);
+
+/* Game <> Host data transfer functions */
+
+extern s32		osTestHost(void);
+extern void		osReadHost(void *, u32);
+extern void		osWriteHost(void *, u32);
+extern void		osAckRamromRead(void);
+extern void		osAckRamromWrite(void);
+
+
+/* byte string operations */
+
+extern void     bcopy(const void *, void *, int);
+extern int      bcmp(const void *, const void *, int);
+extern void     bzero(void *, int);
+
+/* Miscellaneous operations */
+
+extern void		osInitialize(void);
+extern u32		osGetCount(void);
+extern void		osExit(void);
+extern u32 		osGetMemSize(void);
+
+/* Printf */
+
+extern int		sprintf(char *s, const char *fmt, ...);
+extern void		osSyncPrintf(const char *fmt, ...);
+extern void		osAsyncPrintf(const char *fmt, ...);
+extern int		osSyncGetChars(char *buf);
+extern int		osAsyncGetChars(char *buf);
+
+#endif  /* defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS) */
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+}
+#endif
+
+#endif /* !_OS_H */
diff --git a/include/PR/os_internal.h b/include/PR/os_internal.h
new file mode 100644
index 0000000..7f874cd
--- /dev/null
+++ b/include/PR/os_internal.h
@@ -0,0 +1,106 @@
+/**************************************************************************
+ *
+ *  $Revision: 1.18 $
+ *  $Date: 1997/02/11 08:26:14 $
+ *  $Source: /hosts/liberte/disk6/Master/cvsmdev2/PR/include/os_internal.h,v $
+ *
+ **************************************************************************/
+
+#ifndef _OS_INTERNAL_H_
+#define	_OS_INTERNAL_H_
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+extern "C" {
+#endif
+
+#include "PR/os.h"
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+
+#include "os_internal_reg.h"
+#include "os_internal_exception.h"
+
+/* Routines to get/fetch coprocessor 0 registers */
+
+extern u32		__osGetCause(void);
+extern void		__osSetCause(u32);
+extern u32		__osGetCompare(void);
+extern void		__osSetCompare(u32);
+extern u32		__osGetConfig(void);
+extern void		__osSetConfig(u32);
+extern void		__osSetCount(u32);
+extern u32		__osGetSR(void);
+extern void		__osSetSR(u32);
+extern u32		__osDisableInt(void);
+extern void		__osRestoreInt(u32);
+
+/* Routines to get/set floating-point control and status register */
+extern u32              __osSetFpcCsr(u32);
+extern u32              __osGetFpcCsr(void);
+
+/* Routine for global interrupt mask */
+extern void		__osSetGlobalIntMask(OSHWIntr);
+extern void		__osResetGlobalIntMask(OSHWIntr);
+
+/* Routine for global interrupt mask */
+extern s32		__osLeoInterrupt(void);
+
+/* Routines for fetch TLB info */
+
+extern u32		__osGetTLBASID(void);
+extern u32		__osGetTLBPageMask(s32);
+extern u32		__osGetTLBHi(s32);
+extern u32		__osGetTLBLo0(s32);
+extern u32		__osGetTLBLo1(s32);
+
+/* Serial interface (Si) */
+
+extern u32 		__osSiGetStatus(void);
+extern s32		__osSiRawWriteIo(u32, u32);
+extern s32		__osSiRawReadIo(u32, u32 *);
+extern s32		__osSiRawStartDma(s32, void *);
+
+/* Signal processor interface (Sp) */
+
+extern u32 		__osSpGetStatus(void);
+extern void		__osSpSetStatus(u32);
+extern s32		__osSpSetPc(u32);
+extern s32		__osSpRawWriteIo(u32, u32);
+extern s32		__osSpRawReadIo(u32, u32 *);
+extern s32		__osSpRawStartDma(s32, u32, void *, u32);
+
+/* Error handling */
+
+extern void		__osError(s16, s16, ...);
+extern OSThread *	__osGetCurrFaultedThread(void);
+extern OSThread *	__osGetNextFaultedThread(OSThread *);
+
+/* Development board functions */
+
+extern void		__osGIOInit(s32);
+extern void		__osGIOInterrupt(s32);
+extern void		__osGIORawInterrupt(s32);
+
+/* For debugger use */
+
+extern OSThread *	__osGetActiveQueue(void);
+
+/* Debug port */
+extern void		__osSyncPutChars(int, int, const char *);
+extern int		__osSyncGetChars(char *);
+extern void		__osAsyncPutChars(int, int, const char *);
+extern int		__osAsyncGetChars(char *);
+extern int		__osAtomicInc(unsigned int *p);
+extern int		__osAtomicDec(unsigned int *p);
+
+/* routine for rdb port */
+extern u32             __osRdbSend(u8 *buf, u32 size, u32 type);
+
+
+#endif /* _LANGUAGE_C */
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+}
+#endif
+
+#endif /* !_OS_INTERNAL_H */
diff --git a/include/PR/os_internal_exception.h b/include/PR/os_internal_exception.h
new file mode 100644
index 0000000..198657e
--- /dev/null
+++ b/include/PR/os_internal_exception.h
@@ -0,0 +1,36 @@
+/*---------------------------------------------------------------------*
+      
+        $RCSfile: os_internal_exception.h,v $
+        $Revision: 1.1 $
+        $Date: 1998/10/09 08:01:10 $
+ *---------------------------------------------------------------------*/
+
+#ifndef _OS_INTERNAL_EXCEPTION_H_
+#define	_OS_INTERNAL_EXCEPTION_H_
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+extern "C" {
+#endif
+
+#include "PR/os.h"
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+
+/* Routine for HW interrupt "handler" */
+extern void 		__osSetHWIntrRoutine(OSHWIntr interrupt,
+					     s32 (*handler)(void), void *stackEnd);
+extern void 		__osGetHWIntrRoutine(OSHWIntr interrupt,
+					     s32 (**handler)(void), void **stackEnd);
+
+/* Routine for global interrupt mask */
+extern void		__osSetGlobalIntMask(OSHWIntr);
+extern void		__osResetGlobalIntMask(OSHWIntr);
+
+
+#endif /* _LANGUAGE_C */
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+}
+#endif
+
+#endif /* !_OS_INTERNAL_EXCEPTION_H */
diff --git a/include/PR/os_internal_reg.h b/include/PR/os_internal_reg.h
new file mode 100644
index 0000000..6ed720e
--- /dev/null
+++ b/include/PR/os_internal_reg.h
@@ -0,0 +1,46 @@
+/*---------------------------------------------------------------------*
+        
+        $RCSfile: os_internal_reg.h,v $
+        $Revision: 1.2 $
+        $Date: 1999/03/10 12:19:14 $
+ *---------------------------------------------------------------------*/
+
+#ifndef _OS_INTERNAL_REG_H_
+#define	_OS_INTERNAL_REG_H_
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+extern "C" {
+#endif
+
+#include "PR/os.h"
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+
+/* Routines to get/fetch coprocessor 0 registers */
+
+extern u32		__osGetCause(void);
+extern void		__osSetCause(u32);
+extern u32		__osGetCompare(void);
+extern void		__osSetCompare(u32);
+extern u32		__osGetConfig(void);
+extern void		__osSetConfig(u32);
+extern void		__osSetCount(u32);
+extern u32		__osGetSR(void);
+extern void		__osSetSR(u32);
+extern u32		__osDisableInt(void);
+extern void		__osRestoreInt(u32);
+extern u32		__osGetWatchLo(void);
+extern void		__osSetWatchLo(u32);
+
+/* Routines to get/set floating-point control and status register */
+extern u32              __osSetFpcCsr(u32);
+extern u32              __osGetFpcCsr(void);
+
+
+#endif /* _LANGUAGE_C */
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+}
+#endif
+
+#endif /* !_OS_INTERNAL_REG_H */
diff --git a/include/PR/rcp.h b/include/PR/rcp.h
index 2a2b0e2..9a21a87 100644
--- a/include/PR/rcp.h
+++ b/include/PR/rcp.h
@@ -66,6 +66,10 @@
 #define RDRAM_0_DEVICE_ID   0
 #define RDRAM_1_DEVICE_ID   1
 
+#define RDRAM_RESET_MODE    0
+#define RDRAM_ACTIVE_MODE   1
+#define RDRAM_STANDBY_MODE  2
+
 #define RDRAM_LENGTH            (2 * 512 * 2048)
 #define RDRAM_0_BASE_ADDRESS    (RDRAM_0_DEVICE_ID * RDRAM_LENGTH)
 #define RDRAM_1_BASE_ADDRESS    (RDRAM_1_DEVICE_ID * RDRAM_LENGTH)
@@ -74,9 +78,46 @@
 #define RDRAM_1_CONFIG      0x00400
 #define RDRAM_GLOBAL_CONFIG 0x80000
 
-#define RDRAM_RESET_MODE    0
-#define RDRAM_ACTIVE_MODE   1
-#define RDRAM_STANDBY_MODE  2
+/**
+ * PIF Physical memory map (total size = 2 KB)
+ *
+ *            Size      Description     Mode
+ *  1FC007FF    +-------+-----------------+-----+
+ *              |  64 B | JoyChannel RAM  | R/W |
+ *  1FC007C0    +-------+-----------------+-----+
+ *              |1984 B |    Boot ROM     |  *  |  * = Reserved
+ *  1FC00000    +-------+-----------------+-----+
+ */
+#define PIF_ROM_START   0x1FC00000
+#define PIF_ROM_END     0x1FC007BF
+#define PIF_RAM_START   0x1FC007C0
+#define PIF_RAM_END     0x1FC007FF
+
+
+/**
+ * Controller channel 
+ * Each game controller channel has 4 error bits that are defined in bit 6-7 of
+ * the Rx and Tx data size area bytes. Programmers need to clear these bits
+ * when setting the Tx/Rx size area values for a channel
+ */
+#define CHNL_ERR_NORESP		0x80	/* Bit 7 (Rx): No response error */
+#define CHNL_ERR_OVERRUN	0x40	/* Bit 6 (Rx): Overrun error */
+#define CHNL_ERR_FRAME		0x80	/* Bit 7 (Tx): Frame error */
+#define CHNL_ERR_COLLISION	0x40	/* Bit 6 (Tx): Collision error */
+
+#define CHNL_ERR_MASK		0xC0	/* Bit 6-7: channel errors */
+
+
+/**
+ * External device info
+ */
+#define DEVICE_TYPE_CART	0	/* ROM cartridge */
+#define DEVICE_TYPE_BULK	1	/* ROM bulk */
+#define DEVICE_TYPE_64DD	2	/* 64 Disk Drive */
+#define DEVICE_TYPE_SRAM	3	/* SRAM */
+/* 4-6 are reserved */
+#define DEVICE_TYPE_INIT	7	/* initial value */
+/* 8-14 are reserved */
 
 /**
  * Signal Processor (SP) Memory
@@ -87,7 +128,7 @@
 #define SP_IMEM_END     0x04001FFF
 
 /**
- * Signal Processor (SP) Registers
+ * Signal Processor (SP) CP0 Registers
  */
 
 #define SP_BASE_REG         0x04040000
@@ -119,9 +160,6 @@
 //! SP PC (R/W): [11:0] program counter
 #define SP_PC_REG       0x04080000
 
-//! SP IMEM BIST REG (R/W): [6:0] BIST status bits
-#define SP_IBIST_REG        0x04080004
-
 /**
  * SP_MEM_ADDR_REG: bit 12
  */
@@ -195,6 +233,11 @@
 #define SP_SET_CPUSIGNAL        SP_SET_SIG4
 #define SP_STATUS_CPUSIGNAL     SP_STATUS_SIG4
 
+/*
+ * SP IMEM BIST REG (R/W): [6:0] BIST status bits; see below for detail
+ */
+#define SP_IBIST_REG        0x04080004
+
 /*
  * SP_IBIST_REG: write bits
  */
@@ -749,20 +792,23 @@
 #define SI_STATUS_INTERRUPT (1 << 12) // Interrupt is set
 
 /**
- * PIF Physical memory map (total size = 2 KB)
- *
- *            Size      Description     Mode
- *  1FC007FF    +-------+-----------------+-----+
- *          |  64 B | JoyChannel RAM  | R/W |
- *  1FC007C0    +-------+-----------------+-----+
- *          |1984 B |    Boot ROM     |  *  |  * = Reserved
- *  1FC00000    +-------+-----------------+-----+
+ * Development Board GIO Control Registers 
  */
-#define PIF_ROM_START   0x1FC00000
-#define PIF_ROM_END     0x1FC007BF
-#define PIF_RAM_START   0x1FC007C0
-#define PIF_RAM_END     0x1FC007FF
 
+#define GIO_BASE_REG		0x18000000
+
+/* Game to Host Interrupt */
+#define GIO_GIO_INTR_REG	(GIO_BASE_REG+0x000)
+
+/* Game to Host SYNC */
+#define GIO_GIO_SYNC_REG	(GIO_BASE_REG+0x400)
+
+/* Host to Game Interrupt */
+#define GIO_CART_INTR_REG	(GIO_BASE_REG+0x800)
+
+/**
+ * Common macros
+ */
 #if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
 #define	IO_READ(addr)       (*(vu32*)PHYS_TO_K1(addr))
 #define	IO_WRITE(addr,data) (*(vu32*)PHYS_TO_K1(addr)=(u32)(data))
diff --git a/include/PR/rdb.h b/include/PR/rdb.h
new file mode 100644
index 0000000..e149a7c
--- /dev/null
+++ b/include/PR/rdb.h
@@ -0,0 +1,93 @@
+
+/**************************************************************************
+ *
+ *  $Revision: 1.6 $
+ *  $Date: 1997/02/11 08:29:31 $
+ *  $Source: /exdisk2/cvs/N64OS/Master/cvsmdev2/PR/include/rdb.h,v $
+ *
+ **************************************************************************/
+
+#ifndef _RDB_H
+#define _RDB_H
+
+/* U64 side address */
+#define	RDB_BASE_REG		0xc0000000
+#define RDB_WRITE_INTR_REG	(RDB_BASE_REG + 0x8)
+#define RDB_READ_INTR_REG	(RDB_BASE_REG + 0xc)
+#define RDB_BASE_VIRTUAL_ADDR	0x80000000
+
+/* packet type  Have six bits, so can have up to 63 types */
+#define RDB_TYPE_INVALID                0
+#define RDB_TYPE_GtoH_PRINT             1
+#define RDB_TYPE_GtoH_FAULT             2
+#define RDB_TYPE_GtoH_LOG_CT		3
+#define RDB_TYPE_GtoH_LOG               4
+#define RDB_TYPE_GtoH_READY_FOR_DATA    5
+#define RDB_TYPE_GtoH_DATA_CT		6
+#define RDB_TYPE_GtoH_DATA              7
+#define RDB_TYPE_GtoH_DEBUG             8
+#define RDB_TYPE_GtoH_RAMROM		9
+#define RDB_TYPE_GtoH_DEBUG_DONE        10
+#define RDB_TYPE_GtoH_DEBUG_READY       11
+#define RDB_TYPE_GtoH_KDEBUG            12
+#define RDB_TYPE_GtoH_PROF_DATA         22
+
+
+#define RDB_TYPE_HtoG_LOG_DONE		13
+#define RDB_TYPE_HtoG_DEBUG            	14
+#define RDB_TYPE_HtoG_DEBUG_CT          15
+#define RDB_TYPE_HtoG_DATA              16
+#define RDB_TYPE_HtoG_DATA_DONE		17 
+#define RDB_TYPE_HtoG_REQ_RAMROM        18
+#define RDB_TYPE_HtoG_FREE_RAMROM	19
+#define RDB_TYPE_HtoG_KDEBUG            20
+#define RDB_TYPE_HtoG_PROF_SIGNAL       21
+
+
+#define RDB_PROF_ACK_SIG               1
+#define RDB_PROF_FLUSH_SIG             2
+#define PROF_BLOCK_SIZE			2048
+
+#define RDB_LOG_MAX_BLOCK_SIZE         0x8000
+#define RDB_DATA_MAX_BLOCK_SIZE        0x8000
+
+
+/* GIO side address */
+#define GIO_RDB_BASE_REG	0xbf480000
+#define	GIO_RDB_WRITE_INTR_REG	(GIO_RDB_BASE_REG + 0x8)
+#define GIO_RDB_READ_INTR_REG	(GIO_RDB_BASE_REG + 0xc)
+
+/* minor device number */
+#define GIO_RDB_PRINT_MINOR		1
+#define GIO_RDB_DEBUG_MINOR		2
+
+/* interrupt bit */
+#define GIO_RDB_WRITE_INTR_BIT	0x80000000
+#define GIO_RDB_READ_INTR_BIT	0x40000000
+
+/* debug command */
+#define DEBUG_COMMAND_NULL	0
+#define DEBUG_COMMAND_MEMORY	1
+#define DEBUG_COMMAND_REGISTER	2
+#define DEBUG_COMMAND_INVALID	255
+
+/* debug state */
+#define DEBUG_STATE_NULL	0
+#define DEBUG_STATE_RECEIVE	1
+#define DEBUG_STATE_INVALID	255
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+
+/* Structure for debug port */
+typedef struct {
+	unsigned type : 6;	/* 0: invalid, 1: print, 2: debug */
+	unsigned length : 2;	/* 1, 2, or 3 */
+	char buf[3];		/* character buffer */
+} rdbPacket;
+
+extern unsigned int	__osRdbWriteOK;
+extern unsigned int	__osRdbSendMessage;
+
+#endif /* _LANGUAGE_C */
+
+#endif /* !_RDB_H */
diff --git a/include/PR/ultraerror.h b/include/PR/ultraerror.h
new file mode 100644
index 0000000..b5295ab
--- /dev/null
+++ b/include/PR/ultraerror.h
@@ -0,0 +1,145 @@
+/**************************************************************************
+ *
+ *  $Revision: 1.23 $
+ *  $Date: 1997/02/11 08:38:08 $
+ *  $Source: /hosts/liberte/disk6/Master/cvsmdev2/PR/include/ultraerror.h,v $
+ *
+ **************************************************************************/
+
+#ifndef __ULTRAERROR_H__
+#define __ULTRAERROR_H__
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+extern "C" {
+#endif
+
+#include "PR/ultratypes.h"
+
+#define	OS_ERROR_FMT	"/usr/lib/PR/error.fmt"
+#define OS_ERROR_MAGIC	0x6b617479
+
+/* OS error codes */
+
+#define	ERR_OSCREATETHREAD_SP		1
+#define	ERR_OSCREATETHREAD_PRI		2
+#define	ERR_OSSTARTTHREAD		3
+#define	ERR_OSSETTHREADPRI		4
+#define	ERR_OSCREATEMESGQUEUE		5
+#define	ERR_OSSENDMESG			6
+#define	ERR_OSJAMMESG			7
+#define	ERR_OSRECVMESG			8
+#define	ERR_OSSETEVENTMESG		9
+#define	ERR_OSMAPTLB_INDEX		10
+#define	ERR_OSMAPTLB_ASID		11
+#define	ERR_OSUNMAPTLB			12
+#define	ERR_OSSETTLBASID		13
+#define	ERR_OSAISETFREQUENCY		14
+#define	ERR_OSAISETNEXTBUFFER_ADDR	15
+#define	ERR_OSAISETNEXTBUFFER_SIZE	16
+#define	ERR_OSDPSETNEXTBUFFER_ADDR	17
+#define	ERR_OSDPSETNEXTBUFFER_SIZE	18
+#define	ERR_OSPIRAWREADIO		19
+#define	ERR_OSPIRAWWRITEIO		20
+#define	ERR_OSPIRAWSTARTDMA_DIR		21
+#define	ERR_OSPIRAWSTARTDMA_DEVADDR	22
+#define	ERR_OSPIRAWSTARTDMA_ADDR	23
+#define	ERR_OSPIRAWSTARTDMA_SIZE	24
+#define	ERR_OSPIRAWSTARTDMA_RANGE	25
+#define	ERR_OSPIREADIO			26
+#define	ERR_OSPIWRITEIO			27
+#define	ERR_OSPISTARTDMA_PIMGR		28
+#define	ERR_OSPISTARTDMA_PRI		29
+#define	ERR_OSPISTARTDMA_DIR		30
+#define	ERR_OSPISTARTDMA_DEVADDR	31
+#define	ERR_OSPISTARTDMA_ADDR		32
+#define	ERR_OSPISTARTDMA_SIZE		33
+#define	ERR_OSPISTARTDMA_RANGE		34
+#define	ERR_OSCREATEPIMANAGER		35
+#define	ERR_OSVIGETCURRENTMODE		36
+#define	ERR_OSVIGETCURRENTFRAMEBUFFER	37
+#define	ERR_OSVIGETNEXTFRAMEBUFFER	38
+#define	ERR_OSVISETXSCALE_VALUE		39
+#define	ERR_OSVISETXSCALE_VIMGR		40
+#define	ERR_OSVISETYSCALE_VALUE		41
+#define	ERR_OSVISETYSCALE_VIMGR		42
+#define	ERR_OSVISETSPECIAL_VALUE	43
+#define	ERR_OSVISETSPECIAL_VIMGR	44
+#define	ERR_OSVISETMODE			45
+#define	ERR_OSVISETEVENT		46
+#define	ERR_OSVISWAPBUFFER_ADDR		47
+#define	ERR_OSVISWAPBUFFER_VIMGR	48
+#define	ERR_OSCREATEVIMANAGER		49
+#define	ERR_OSCREATEREGION_ALIGN	50
+#define	ERR_OSCREATEREGION_SIZE		51
+#define	ERR_OSMALLOC			52
+#define	ERR_OSFREE_REGION		53
+#define	ERR_OSFREE_ADDR			54
+#define	ERR_OSGETREGIONBUFCOUNT		55
+#define	ERR_OSGETREGIONBUFSIZE		56
+#define	ERR_OSSPTASKLOAD_DRAM		57
+#define	ERR_OSSPTASKLOAD_OUT		58
+#define	ERR_OSSPTASKLOAD_OUTSIZE	59
+#define	ERR_OSSPTASKLOAD_YIELD		60
+#define ERR_OSPROFILEINIT_STR		61
+#define ERR_OSPROFILEINIT_CNT		62
+#define ERR_OSPROFILEINIT_ALN		63
+#define ERR_OSPROFILEINIT_ORD		64
+#define	ERR_OSPROFILEINIT_SIZ		65
+#define ERR_OSPROFILESTART_TIME		66
+#define ERR_OSPROFILESTART_FLAG		67
+#define	ERR_OSPROFILESTOP_FLAG		68
+#define ERR_OSPROFILESTOP_TIMER		69
+#define	ERR_OSREADHOST_ADDR		70
+#define	ERR_OSREADHOST_SIZE		71
+#define	ERR_OSWRITEHOST_ADDR		72
+#define	ERR_OSWRITEHOST_SIZE		73
+#define	ERR_OSGETTIME			74
+#define	ERR_OSSETTIME			75
+#define	ERR_OSSETTIMER			76
+#define	ERR_OSSTOPTIMER			77
+#define	ERR_ALSEQP_NO_SOUND		100
+#define	ERR_ALSEQP_NO_VOICE		101
+#define	ERR_ALSEQP_MAP_VOICE		102
+#define	ERR_ALSEQP_OFF_VOICE		103
+#define	ERR_ALSEQP_POLY_VOICE		104
+#define	ERR_ALSNDP_NO_VOICE		105
+#define	ERR_ALSYN_NO_UPDATE		106
+#define	ERR_ALSNDPDEALLOCATE		107
+#define	ERR_ALSNDPDELETE		108
+#define	ERR_ALSNDPPLAY			109
+#define	ERR_ALSNDPSETSOUND		110
+#define ERR_ALSNDPSETPRIORITY           111
+#define ERR_ALSNDPSETPAR                112
+#define	ERR_ALBNKFNEW			113
+#define ERR_ALSEQNOTMIDI                114
+#define ERR_ALSEQNOTMIDI0               115
+#define ERR_ALSEQNUMTRACKS              116
+#define ERR_ALSEQTIME                   117
+#define ERR_ALSEQTRACKHDR               118
+#define ERR_ALSEQSYSEX                  119
+#define ERR_ALSEQMETA                   120
+#define ERR_ALSEQPINVALIDPROG           121
+#define ERR_ALSEQPUNKNOWNMIDI           122
+#define ERR_ALSEQPUNMAP                 123
+#define ERR_ALEVENTNOFREE               124
+#define ERR_ALHEAPNOFREE                125
+#define ERR_ALHEAPCORRUPT               126
+#define ERR_ALHEAPFIRSTBLOCK            127
+#define ERR_ALCSEQZEROSTATUS		128
+#define ERR_ALCSEQZEROVEL		129
+#define ERR_ALCSPVNOTFREE		130
+#define ERR_ALSEQOVERRUN		131
+#define ERR_OSAISETNEXTBUFFER_ENDADDR	132
+#define ERR_ALMODDELAYOVERFLOW          133
+
+#if defined(_LANGUAGE_C) || defined(_LANGUAGE_C_PLUS_PLUS)
+typedef	void (*OSErrorHandler)(s16, s16, ...);
+
+OSErrorHandler	osSetErrorHandler(OSErrorHandler);
+#endif
+
+#ifdef _LANGUAGE_C_PLUS_PLUS
+}
+#endif
+
+#endif	/* __ULTRAERROR_H__ */
diff --git a/src/os/ackramromread.c b/src/os/ackramromread.c
new file mode 100644
index 0000000..4aea863
--- /dev/null
+++ b/src/os/ackramromread.c
@@ -0,0 +1,8 @@
+#include "PR/os_internal.h"
+
+// TODO: this comes from a header
+#ident "$Revision: 1.4 $"
+
+void osAckRamromRead() {
+
+}
diff --git a/src/os/ackramromwrite.c b/src/os/ackramromwrite.c
new file mode 100644
index 0000000..34fe2ad
--- /dev/null
+++ b/src/os/ackramromwrite.c
@@ -0,0 +1,8 @@
+#include "PR/os_internal.h"
+
+// TODO: this comes from a header
+#ident "$Revision: 1.4 $"
+
+void osAckRamromWrite() {
+
+}
diff --git a/src/os/assert.c b/src/os/assert.c
new file mode 100644
index 0000000..d076a24
--- /dev/null
+++ b/src/os/assert.c
@@ -0,0 +1,5 @@
+#include "PR/os_internal.h"
+
+void __assert(const char *exp, const char *filename, int line) {
+    osSyncPrintf("\nASSERTION FAULT: %s, %d: \"%s\"\n", filename, line, exp);
+}
diff --git a/src/os/atomic.c b/src/os/atomic.c
new file mode 100644
index 0000000..f96bb63
--- /dev/null
+++ b/src/os/atomic.c
@@ -0,0 +1,15 @@
+#include "PR/os_internal.h"
+
+int __osAtomicDec(unsigned int *p) {
+    register u32 saveMask = __osDisableInt();
+    int mask;
+
+    if (*p) {
+        (*p)--;
+        mask = 1;
+    } else {
+        mask = 0;
+    }
+    __osRestoreInt(saveMask);
+    return mask;
+}
diff --git a/src/os/createmesgqueue.c b/src/os/createmesgqueue.c
new file mode 100644
index 0000000..4e71cba
--- /dev/null
+++ b/src/os/createmesgqueue.c
@@ -0,0 +1,11 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osCreateMesgQueue(OSMesgQueue *mq, OSMesg *msg, s32 msgCount) {
+    mq->mtqueue = &__osThreadTail.next;
+    mq->fullqueue = &__osThreadTail.next;
+    mq->validCount = 0;
+    mq->first = 0;
+    mq->msgCount = msgCount;
+    mq->msg = msg;
+}
diff --git a/src/os/createthread.c b/src/os/createthread.c
new file mode 100644
index 0000000..1ae9f0b
--- /dev/null
+++ b/src/os/createthread.c
@@ -0,0 +1,27 @@
+#include "PR/os_internal.h"
+#include "PR/R4300.h"
+#include "osint.h"
+
+void osCreateThread(OSThread *t, OSId id, void (*entry)(void *), void *arg, void *sp, OSPri p) {
+    register u32 saveMask;
+    OSIntMask mask;
+    t->id = id;
+    t->priority = p;
+    t->next = NULL;
+    t->queue = NULL;
+    t->context.pc = (u32)entry;
+    t->context.a0 = (s64)(s32)arg; // Double cast gets rid of compiler warning
+    t->context.sp = (s64)(s32)sp - 16;
+    t->context.ra = (u64)__osCleanupThread;
+    mask = OS_IM_ALL;
+    t->context.sr = SR_IMASK | SR_EXL | SR_IE;
+    t->context.rcp = (mask & RCP_IMASK) >> RCP_IMASKSHIFT;
+    t->context.fpcsr = (u32)(FPCSR_FS | FPCSR_EV);
+    t->fp = 0;
+    t->state = OS_STATE_STOPPED;
+    t->flags = 0;
+    saveMask = __osDisableInt();
+    t->tlnext = __osActiveQueue;
+    __osActiveQueue = t;
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/destroythread.c b/src/os/destroythread.c
new file mode 100644
index 0000000..43d2436
--- /dev/null
+++ b/src/os/destroythread.c
@@ -0,0 +1,37 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osDestroyThread(OSThread *t) {
+    register u32 saveMask;
+    register OSThread *pred;
+    register OSThread *succ;
+
+    saveMask = __osDisableInt();
+
+    if (t == NULL) {
+        t = __osRunningThread;
+    } else if (t->state != OS_STATE_STOPPED) {
+        __osDequeueThread(t->queue, t);
+    }
+
+    if (__osActiveQueue == t) {
+        __osActiveQueue = __osActiveQueue->tlnext;
+    } else {
+        pred = __osActiveQueue;
+        while (pred->priority != -1) {
+            succ = pred->tlnext;
+            if (succ == t) {
+                pred->tlnext = t->tlnext;
+                break;
+            }
+            pred = succ;
+            succ = pred->tlnext;
+        }
+    }
+
+    if (t == __osRunningThread) {
+        __osDispatchThread();
+    }
+    
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/exit.c b/src/os/exit.c
new file mode 100644
index 0000000..d5e60eb
--- /dev/null
+++ b/src/os/exit.c
@@ -0,0 +1,8 @@
+#include "PR/os_internal.h"
+
+void osExit() {
+    __osGIOInterrupt(16);
+
+    for (;;);
+}
+
diff --git a/src/os/getactivequeue.c b/src/os/getactivequeue.c
new file mode 100644
index 0000000..4175e7d
--- /dev/null
+++ b/src/os/getactivequeue.c
@@ -0,0 +1,6 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSThread *__osGetActiveQueue(void) {
+    return __osActiveQueue;
+}
diff --git a/src/os/getcurrfaultthread.c b/src/os/getcurrfaultthread.c
new file mode 100644
index 0000000..7500928
--- /dev/null
+++ b/src/os/getcurrfaultthread.c
@@ -0,0 +1,6 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSThread *__osGetCurrFaultedThread() {
+    return __osFaultedThread;
+}
diff --git a/src/os/getmemsize.c b/src/os/getmemsize.c
new file mode 100644
index 0000000..44fbc19
--- /dev/null
+++ b/src/os/getmemsize.c
@@ -0,0 +1,35 @@
+#include "PR/os_internal.h"
+#include "PR/rcp.h"
+#include "PR/R4300.h"
+
+#define STEP 0x100000
+#define SIZE_4MB 0x400000
+#define SIZE_8MB 0x800000
+
+u32 osGetMemSize(void) {
+    vu32* ptr;
+    u32 size = SIZE_4MB;
+    u32 data0;
+    u32 data1;
+
+    while (size < SIZE_8MB) {
+        ptr = (vu32*)(K1BASE + size);
+
+        data0 = *ptr;
+        data1 = ptr[STEP / 4 - 1];
+
+        *ptr ^= ~0;
+        ptr[STEP / 4 - 1] ^= ~0;
+
+        if ((*ptr != (data0 ^ ~0)) || (ptr[STEP / 4 - 1] != (data1 ^ ~0))) {
+            return size;
+        }
+
+        *ptr = data0;
+        ptr[STEP / 4 - 1] = data1;
+
+        size += STEP;
+    }
+
+    return size;
+}
diff --git a/src/os/getnextfaultthread.c b/src/os/getnextfaultthread.c
new file mode 100644
index 0000000..9add6dd
--- /dev/null
+++ b/src/os/getnextfaultthread.c
@@ -0,0 +1,28 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSThread *__osGetNextFaultedThread(OSThread *lastFault) {
+    register int saveMask = __osDisableInt();
+    register OSThread *fault;
+
+    if (lastFault == NULL) {
+        fault = __osActiveQueue;
+    } else {
+        fault = lastFault;
+    }
+
+    while (fault->priority != -1) {
+        if ((fault->flags & OS_FLAG_FAULT) != 0 && fault != lastFault) {
+            break;
+        }
+        fault = fault->tlnext;
+    }
+
+    if (fault->priority == -1) {
+        fault = NULL;
+    }
+
+    __osRestoreInt(saveMask);
+    return fault;
+}
+
diff --git a/src/os/getthreadid.c b/src/os/getthreadid.c
new file mode 100644
index 0000000..9aac16d
--- /dev/null
+++ b/src/os/getthreadid.c
@@ -0,0 +1,10 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSId osGetThreadId(OSThread *thread) {
+    if (thread == NULL) {
+        thread = __osRunningThread;
+    }
+
+    return thread->id;
+}
diff --git a/src/os/getthreadpri.c b/src/os/getthreadpri.c
new file mode 100644
index 0000000..a1e9ce2
--- /dev/null
+++ b/src/os/getthreadpri.c
@@ -0,0 +1,10 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSPri osGetThreadPri(OSThread *thread) {
+    if (thread == NULL) {
+        thread = __osRunningThread;
+    }
+    
+    return thread->priority;
+}
diff --git a/src/os/gettime.c b/src/os/gettime.c
new file mode 100644
index 0000000..aee799a
--- /dev/null
+++ b/src/os/gettime.c
@@ -0,0 +1,15 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSTime osGetTime() {
+    u32 tmptime;
+    u32 elapseCount;
+    OSTime currentCount;
+    register u32 saveMask;
+    saveMask = __osDisableInt();
+    tmptime = osGetCount();
+    elapseCount = tmptime - __osBaseCounter;
+    currentCount = __osCurrentTime;
+    __osRestoreInt(saveMask);
+    return currentCount + elapseCount;
+}
diff --git a/src/os/initialize.c b/src/os/initialize.c
new file mode 100644
index 0000000..7cd169f
--- /dev/null
+++ b/src/os/initialize.c
@@ -0,0 +1,85 @@
+#include "PR/os_internal.h"
+#include "PR/rcp.h"
+
+typedef struct
+{
+   /* 0x0 */ unsigned int inst1;
+   /* 0x4 */ unsigned int inst2;
+   /* 0x8 */ unsigned int inst3;
+   /* 0xC */ unsigned int inst4;
+} __osExceptionVector;
+extern __osExceptionVector __osExceptionPreamble;
+
+extern OSPiHandle __Dom1SpeedParam;
+extern OSPiHandle __Dom2SpeedParam;
+
+OSTime osClockRate = OS_CLOCK_RATE;
+s32 osViClock = VI_NTSC_CLOCK;
+u32 __osShutdown = 0;
+u32 __OSGlobalIntMask = OS_IM_ALL;
+u32 __osFinalrom;
+
+void __createSpeedParam(void) {
+    __Dom1SpeedParam.type = DEVICE_TYPE_INIT;
+    __Dom1SpeedParam.latency = IO_READ(PI_BSD_DOM1_LAT_REG);
+    __Dom1SpeedParam.pulse = IO_READ(PI_BSD_DOM1_PWD_REG);
+    __Dom1SpeedParam.pageSize = IO_READ(PI_BSD_DOM1_PGS_REG);
+    __Dom1SpeedParam.relDuration = IO_READ(PI_BSD_DOM1_RLS_REG);
+
+    __Dom2SpeedParam.type = DEVICE_TYPE_INIT;
+    __Dom2SpeedParam.latency = IO_READ(PI_BSD_DOM2_LAT_REG);
+    __Dom2SpeedParam.pulse = IO_READ(PI_BSD_DOM2_PWD_REG);
+    __Dom2SpeedParam.pageSize = IO_READ(PI_BSD_DOM2_PGS_REG);
+    __Dom2SpeedParam.relDuration = IO_READ(PI_BSD_DOM2_RLS_REG);
+}
+
+void __osInitialize_common() {
+    u32 pifdata;
+    __osFinalrom = TRUE;
+    __osSetSR(__osGetSR() | SR_CU1);    //enable fpu
+    __osSetFpcCsr(FPCSR_FS | FPCSR_EV); //flush denorm to zero, enable invalid operation
+    __osSetWatchLo(0x4900000);
+
+    while (__osSiRawReadIo(PIF_RAM_END - 3, &pifdata)) { //last byte of joychannel ram
+        ;
+    }
+    while (__osSiRawWriteIo(PIF_RAM_END - 3, pifdata | 8)) {
+        ; //todo: magic contant
+    }
+    *(__osExceptionVector *)UT_VEC = __osExceptionPreamble;
+    *(__osExceptionVector *)XUT_VEC = __osExceptionPreamble;
+    *(__osExceptionVector *)ECC_VEC = __osExceptionPreamble;
+    *(__osExceptionVector *)E_VEC = __osExceptionPreamble;
+    osWritebackDCache((void *)UT_VEC, E_VEC - UT_VEC + sizeof(__osExceptionVector));
+    osInvalICache((void *)UT_VEC, E_VEC - UT_VEC + sizeof(__osExceptionVector));
+    __createSpeedParam();
+    osUnmapTLBAll();
+    osMapTLBRdb();
+    osClockRate = osClockRate * 3 / 4;
+
+    if (osResetType == 0 ) { // cold reset
+        bzero(osAppNMIBuffer, OS_APP_NMI_BUFSIZE);
+    }
+
+    if (osTvType == OS_TV_PAL) {
+        osViClock = VI_PAL_CLOCK;
+    } else if (osTvType == OS_TV_MPAL) {
+        osViClock = VI_MPAL_CLOCK;
+    } else {
+        osViClock = VI_NTSC_CLOCK;
+    }
+
+    // Wait until there are no RCP interrupts
+    if (__osGetCause() & CAUSE_IP5) {
+        while (TRUE) {
+            ;
+        }
+    }
+
+    IO_WRITE(AI_CONTROL_REG, AI_CONTROL_DMA_ON);
+    IO_WRITE(AI_DACRATE_REG, AI_MAX_DAC_RATE - 1);
+    IO_WRITE(AI_BITRATE_REG, AI_MAX_BIT_RATE - 1);
+}
+
+void __osInitialize_autodetect() {
+}
diff --git a/src/os/initrdb.c b/src/os/initrdb.c
new file mode 100644
index 0000000..9ead917
--- /dev/null
+++ b/src/os/initrdb.c
@@ -0,0 +1 @@
+//not included in the rom build of libultra
diff --git a/src/os/jammesg.c b/src/os/jammesg.c
new file mode 100644
index 0000000..289d850
--- /dev/null
+++ b/src/os/jammesg.c
@@ -0,0 +1,27 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+s32 osJamMesg(OSMesgQueue *mq, OSMesg msg, s32 flag) {
+    register u32 saveMask = __osDisableInt();
+
+    while (mq->validCount >= mq->msgCount) {
+        if (flag == OS_MESG_BLOCK) {
+            __osRunningThread->state = OS_STATE_WAITING;
+            __osEnqueueAndYield(&mq->fullqueue);
+        } else {
+            __osRestoreInt(saveMask);
+            return -1;
+        }
+    }
+
+    mq->first = (mq->first + mq->msgCount - 1) % mq->msgCount;
+    mq->msg[mq->first] = msg;
+    mq->validCount++;
+
+    if (mq->mtqueue->next != NULL) {
+        osStartThread(__osPopThread(&mq->mtqueue));
+    }
+    
+    __osRestoreInt(saveMask);
+    return 0;
+}
diff --git a/src/os/kdebugserver.c b/src/os/kdebugserver.c
new file mode 100644
index 0000000..c98009b
--- /dev/null
+++ b/src/os/kdebugserver.c
@@ -0,0 +1,4 @@
+#include "PR/os_internal.h"
+
+//not included in final rom, but __osThreadSave is here for some reason
+OSThread __osThreadSave;
diff --git a/src/os/osint.h b/src/os/osint.h
new file mode 100644
index 0000000..a68d02f
--- /dev/null
+++ b/src/os/osint.h
@@ -0,0 +1,50 @@
+#ifndef _OSINT_H
+#define _OSINT_H
+#include "PR/os_internal.h"
+typedef struct __OSEventState
+{
+    OSMesgQueue *messageQueue;
+    OSMesg message;
+} __OSEventState;
+extern struct __osThreadTail
+{
+    OSThread *next;
+    OSPri priority;
+} __osThreadTail;
+
+//maybe should be in exceptasm.h?
+extern void __osEnqueueAndYield(OSThread **);
+extern void __osDequeueThread(OSThread **, OSThread *);
+extern void __osEnqueueThread(OSThread **, OSThread *);
+extern OSThread *__osPopThread(OSThread **);
+extern void __osDispatchThread(void);
+extern void __osCleanupThread(void);
+
+extern void __osSetTimerIntr(OSTime);
+extern OSTime __osInsertTimer(OSTimer *);
+extern void __osTimerInterrupt(void);
+extern u32 __osProbeTLB(void *);
+extern int     __osSpDeviceBusy(void);
+
+extern OSThread *__osRunningThread;
+extern OSThread *__osActiveQueue;
+extern OSThread *__osFaultedThread;
+extern OSThread *__osRunQueue;
+
+extern OSTimer *__osTimerList;
+extern OSTimer __osBaseTimer;
+extern OSTime __osCurrentTime;
+extern u32 __osBaseCounter;
+extern u32 __osViIntrCount;
+extern u32 __osTimerCounter;
+extern u32 __osShutdown;
+
+extern __OSEventState __osEventStateTab[OS_NUM_EVENTS];
+
+
+//not sure if this should be here
+extern s32 osViClock;
+extern void __osTimerServicesInit(void);
+extern s32 __osAiDeviceBusy(void);
+extern int __osDpDeviceBusy(void);
+#endif
diff --git a/src/os/physicaltovirtual.c b/src/os/physicaltovirtual.c
new file mode 100644
index 0000000..a0c1bae
--- /dev/null
+++ b/src/os/physicaltovirtual.c
@@ -0,0 +1,6 @@
+#include "PR/os_internal.h"
+#include "PR/R4300.h"
+
+void *osPhysicalToVirtual(u32 addr) {
+    return (void *)PHYS_TO_K0(addr);
+}
diff --git a/src/os/rdbsend.c b/src/os/rdbsend.c
new file mode 100644
index 0000000..b561d99
--- /dev/null
+++ b/src/os/rdbsend.c
@@ -0,0 +1 @@
+/* this file is completely empty in the rom release */
diff --git a/src/os/recvmesg.c b/src/os/recvmesg.c
new file mode 100644
index 0000000..f7f0e63
--- /dev/null
+++ b/src/os/recvmesg.c
@@ -0,0 +1,31 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+s32 osRecvMesg(OSMesgQueue *mq, OSMesg *msg, s32 flags) {
+    register u32 saveMask;
+    saveMask = __osDisableInt();
+
+    while (MQ_IS_EMPTY(mq)) {
+        if (flags == OS_MESG_NOBLOCK) {
+            __osRestoreInt(saveMask);
+            return -1;
+        }
+
+        __osRunningThread->state = OS_STATE_WAITING;
+        __osEnqueueAndYield(&mq->mtqueue);
+    }
+
+    if (msg != NULL) {
+        *msg = mq->msg[mq->first];
+    }
+
+    mq->first = (mq->first + 1) % mq->msgCount;
+    mq->validCount--;
+
+    if (mq->fullqueue->next != NULL) {
+        osStartThread(__osPopThread(&mq->fullqueue));
+    }
+    
+    __osRestoreInt(saveMask);
+    return 0;
+}
diff --git a/src/os/resetglobalintmask.c b/src/os/resetglobalintmask.c
new file mode 100644
index 0000000..780da7c
--- /dev/null
+++ b/src/os/resetglobalintmask.c
@@ -0,0 +1,9 @@
+#include "PR/os_internal.h"
+
+void __osResetGlobalIntMask(OSHWIntr mask) {
+    register u32 saveMask = __osDisableInt();
+
+    __OSGlobalIntMask &= ~(mask & ~OS_IM_RCP);
+
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/sendmesg.c b/src/os/sendmesg.c
new file mode 100644
index 0000000..4d48d08
--- /dev/null
+++ b/src/os/sendmesg.c
@@ -0,0 +1,28 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+s32 osSendMesg(OSMesgQueue *mq, OSMesg msg, s32 flags) {
+    register u32 saveMask;
+    register s32 last;
+    saveMask = __osDisableInt();
+    while (MQ_IS_FULL(mq)) {
+        if (flags == OS_MESG_BLOCK) {
+            __osRunningThread->state = OS_STATE_WAITING;
+            __osEnqueueAndYield(&mq->fullqueue);
+        } else {
+            __osRestoreInt(saveMask);
+            return -1;
+        }
+    }
+    
+    last = (mq->first + mq->validCount) % mq->msgCount;
+    mq->msg[last] = msg;
+    mq->validCount++;
+    
+    if (mq->mtqueue->next != NULL) {
+        osStartThread(__osPopThread(&mq->mtqueue));
+    }
+    
+    __osRestoreInt(saveMask);
+    return 0;
+}
diff --git a/src/os/seterrorhandler.c b/src/os/seterrorhandler.c
new file mode 100644
index 0000000..4e839e8
--- /dev/null
+++ b/src/os/seterrorhandler.c
@@ -0,0 +1,10 @@
+#include "PR/ultraerror.h"
+
+extern OSErrorHandler __osErrorHandler;
+
+OSErrorHandler osSetErrorHandler(OSErrorHandler handler) {
+    OSErrorHandler oldHandler = __osErrorHandler;
+
+    __osErrorHandler = handler;
+    return oldHandler;
+}
diff --git a/src/os/seteventmesg.c b/src/os/seteventmesg.c
new file mode 100644
index 0000000..dd2ad99
--- /dev/null
+++ b/src/os/seteventmesg.c
@@ -0,0 +1,23 @@
+#include "macros.h"
+#include "PR/os_internal.h"
+#include "osint.h"
+
+__OSEventState __osEventStateTab[OS_NUM_EVENTS] ALIGNED(8);
+u32 __osPreNMI = FALSE;
+
+void osSetEventMesg(OSEvent event, OSMesgQueue *mq, OSMesg msg) {
+	register u32 saveMask = __osDisableInt();
+	__OSEventState *es = &__osEventStateTab[event];
+
+	es->messageQueue = mq;
+	es->message = msg;
+
+    if (event == OS_EVENT_PRENMI) {
+        if (__osShutdown && !__osPreNMI) {
+            osSendMesg(mq, msg, OS_MESG_NOBLOCK);
+        }
+        __osPreNMI = TRUE;
+    }
+
+	__osRestoreInt(saveMask);
+}
diff --git a/src/os/setglobalintmask.c b/src/os/setglobalintmask.c
index 9d6d5f6..1d82b6e 100644
--- a/src/os/setglobalintmask.c
+++ b/src/os/setglobalintmask.c
@@ -1,17 +1,9 @@
-#include "PR/ultratypes.h"
+#include "PR/os_internal.h"
 
-typedef u32 OSEvent;
-typedef u32 OSIntMask;
-typedef u32 OSPageMask;
-typedef u32 OSHWIntr;
-
-extern OSIntMask __OSGlobalIntMask;	/* global interrupt mask */
-extern u32		__osDisableInt(void);
-extern void		__osRestoreInt(u32);
-
-void __osSetGlobalIntMask(OSHWIntr mask)
-{
+void __osSetGlobalIntMask(OSHWIntr mask) {
     register u32 saveMask = __osDisableInt();
+
     __OSGlobalIntMask |= mask;
+    
     __osRestoreInt(saveMask);
 }
diff --git a/src/os/sethwinterrupt.c b/src/os/sethwinterrupt.c
new file mode 100644
index 0000000..0fc9d30
--- /dev/null
+++ b/src/os/sethwinterrupt.c
@@ -0,0 +1,16 @@
+#include "PR/os_internal.h"
+
+struct __osHwInt {
+    s32 (*handler)(void);
+    void *stackEnd;
+};
+
+extern struct __osHwInt __osHwIntTable[];
+
+void __osSetHWIntrRoutine(OSHWIntr interrupt, s32 (*handler)(void), void *stackEnd) {
+    register u32 saveMask= __osDisableInt();
+
+    __osHwIntTable[interrupt].handler = handler;
+    __osHwIntTable[interrupt].stackEnd = stackEnd;
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/setthreadpri.c b/src/os/setthreadpri.c
new file mode 100644
index 0000000..ab6b23e
--- /dev/null
+++ b/src/os/setthreadpri.c
@@ -0,0 +1,26 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osSetThreadPri(OSThread *t, OSPri pri) {
+    register u32 saveMask = __osDisableInt();
+    
+    if (t == NULL) {
+        t = __osRunningThread;
+    }
+
+    if (t->priority != pri) {
+        t->priority = pri;
+        
+        if (t != __osRunningThread && t->state != OS_STATE_STOPPED) {
+            __osDequeueThread(t->queue, t);
+            __osEnqueueThread(t->queue, t);
+        }
+
+        if (__osRunningThread->priority < __osRunQueue->priority) {
+            __osRunningThread->state = OS_STATE_RUNNABLE;
+            __osEnqueueAndYield(&__osRunQueue);
+        }
+    }
+
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/settime.c b/src/os/settime.c
new file mode 100644
index 0000000..5bae2a2
--- /dev/null
+++ b/src/os/settime.c
@@ -0,0 +1,6 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osSetTime(OSTime time) {
+    __osCurrentTime = time;
+}
diff --git a/src/os/settimer.c b/src/os/settimer.c
new file mode 100644
index 0000000..0b78f27
--- /dev/null
+++ b/src/os/settimer.c
@@ -0,0 +1,41 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+int osSetTimer(OSTimer *t, OSTime countdown, OSTime interval, OSMesgQueue *mq, OSMesg msg) {
+    register u32 saveMask;
+    OSTime time;
+    OSTimer* next;
+    u32 count;
+    u32 value;
+
+    t->next = NULL;
+    t->prev = NULL;
+    t->value = countdown;
+    t->interval = interval;
+
+    if (countdown == 0) {
+        t->value = interval;
+    }
+
+    t->mq = mq;
+    t->msg = msg;
+    
+    saveMask = __osDisableInt();
+    if (__osTimerList->next != __osTimerList) {
+        next = __osTimerList->next;
+        count = osGetCount();
+        value = count - __osTimerCounter;
+
+        if (value < next->value) {
+            next->value -= value;
+        } else {
+            next->value = 1;
+        }
+    }
+
+    time = __osInsertTimer(t);
+    __osSetTimerIntr(__osTimerList->next->value);
+    __osRestoreInt(saveMask);
+
+    return 0;
+}
diff --git a/src/os/startthread.c b/src/os/startthread.c
new file mode 100644
index 0000000..deef4ed
--- /dev/null
+++ b/src/os/startthread.c
@@ -0,0 +1,35 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osStartThread(OSThread *t) {
+    register u32 saveMask = __osDisableInt();
+    
+    switch (t->state) {
+        case OS_STATE_WAITING:
+            t->state = OS_STATE_RUNNABLE;
+            __osEnqueueThread(&__osRunQueue, t);
+            break;
+        case OS_STATE_STOPPED:
+            if (t->queue == NULL || t->queue == &__osRunQueue)
+            {
+                t->state = OS_STATE_RUNNABLE;
+                __osEnqueueThread(&__osRunQueue, t);
+            }
+            else
+            {
+                t->state = OS_STATE_WAITING;
+                __osEnqueueThread(t->queue, t);
+                __osEnqueueThread(&__osRunQueue, __osPopThread(t->queue));
+            }
+            break;
+    }
+
+    if (__osRunningThread == NULL) {
+        __osDispatchThread();
+    } else if (__osRunningThread->priority < __osRunQueue->priority) {
+        __osRunningThread->state = OS_STATE_RUNNABLE;
+        __osEnqueueAndYield(&__osRunQueue);
+    }
+
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/stopthread.c b/src/os/stopthread.c
new file mode 100644
index 0000000..d276b3b
--- /dev/null
+++ b/src/os/stopthread.c
@@ -0,0 +1,25 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osStopThread(OSThread *t) {
+    register u32 saveMask = __osDisableInt();
+    register u16 state = OS_STATE_RUNNING;
+
+    if (t != NULL) {
+        state = t->state;
+    }
+
+    switch (state) {
+        case OS_STATE_RUNNING:
+            __osRunningThread->state = OS_STATE_STOPPED;
+            __osEnqueueAndYield(NULL);
+            break;
+        case OS_STATE_RUNNABLE:
+        case OS_STATE_WAITING:
+            t->state = OS_STATE_STOPPED;
+            __osDequeueThread(t->queue, t);
+            break;
+    }
+
+    __osRestoreInt(saveMask);
+}
diff --git a/src/os/stoptimer.c b/src/os/stoptimer.c
new file mode 100644
index 0000000..e9e07af
--- /dev/null
+++ b/src/os/stoptimer.c
@@ -0,0 +1,30 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+int osStopTimer(OSTimer *t) {
+    register u32 savedMask;
+    OSTimer *timep;
+
+    if (t->next == NULL) {
+        return -1;
+    }
+
+    savedMask = __osDisableInt();
+    timep = t->next;
+
+    if (timep != __osTimerList) {
+        timep->value += t->value;
+    }
+
+    t->prev->next = t->next;
+    t->next->prev = t->prev;
+    t->next = NULL;
+    t->prev = NULL;
+
+    if (__osTimerList->next == __osTimerList) {
+        __osSetCompare(0);
+    }
+
+    __osRestoreInt(savedMask);
+    return 0;
+}
diff --git a/src/os/syncputchars.c b/src/os/syncputchars.c
new file mode 100644
index 0000000..9095a04
--- /dev/null
+++ b/src/os/syncputchars.c
@@ -0,0 +1,32 @@
+#include "PR/os_internal.h"
+#include "PR/rdb.h"
+#include "PR/rcp.h"
+#include "PR/R4300.h"
+
+unsigned int __osRdbSendMessage = 0;
+unsigned int __osRdbWriteOK = 1;
+
+void __osSyncPutChars(int type, int length, const char *buf) {
+   rdbPacket packet;
+   int i;
+   u32 mask;
+   packet.type = type;
+   packet.length = length;
+   
+   for (i = 0; i < length; i++) {
+      packet.buf[i] = buf[i];
+   }
+
+   while (!__osAtomicDec(&__osRdbWriteOK)) {
+   }
+
+   mask = __osDisableInt();
+   *(vu32 *)RDB_BASE_REG = *(vu32 *)&packet;
+
+   while (!(__osGetCause() & CAUSE_IP6)) {
+   }
+
+   *(vu32 *)RDB_READ_INTR_REG = 0;
+   __osRdbWriteOK++;
+   __osRestoreInt(mask);
+}
diff --git a/src/os/testhost.c b/src/os/testhost.c
new file mode 100644
index 0000000..70514eb
--- /dev/null
+++ b/src/os/testhost.c
@@ -0,0 +1,4 @@
+#include "PR/os_internal.h"
+
+// TODO: this comes from a header
+#ident "$Revision: 1.4 $"
diff --git a/src/os/thread.c b/src/os/thread.c
new file mode 100644
index 0000000..767c4cf
--- /dev/null
+++ b/src/os/thread.c
@@ -0,0 +1,25 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+struct __osThreadTail __osThreadTail = {NULL, -1};
+OSThread *__osRunQueue = (OSThread *)&__osThreadTail;
+OSThread *__osActiveQueue = (OSThread *)&__osThreadTail;
+OSThread *__osRunningThread = {0};
+OSThread *__osFaultedThread = {0};
+
+void __osDequeueThread(OSThread **queue, OSThread *t) {
+    register OSThread **pred;
+    register OSThread *succ;
+
+    pred = queue;
+    succ = *pred;
+
+    while (succ != NULL) {
+        if (succ == t) {
+            *pred = t->next;
+            return;
+        }
+        pred = succ;
+        succ = *pred;
+    }
+}
diff --git a/src/os/timerintr.c b/src/os/timerintr.c
new file mode 100644
index 0000000..0f09d1f
--- /dev/null
+++ b/src/os/timerintr.c
@@ -0,0 +1,106 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+OSTimer *__osTimerList = &__osBaseTimer;
+OSTimer __osBaseTimer;
+OSTime __osCurrentTime;
+u32 __osBaseCounter;
+u32 __osViIntrCount;
+u32 __osTimerCounter;
+
+void __osTimerServicesInit(void) {
+	__osCurrentTime = 0;
+	__osBaseCounter = 0;
+	__osViIntrCount = 0;
+	__osTimerList->prev = __osTimerList;
+	__osTimerList->next = __osTimerList->prev;
+	__osTimerList->value = 0;
+	__osTimerList->interval = __osTimerList->value;
+	__osTimerList->mq = NULL;
+	__osTimerList->msg = 0;
+}
+
+void __osTimerInterrupt(void) {
+	OSTimer *t;
+	u32 count;
+	u32 elapsed_cycles;
+
+	if (__osTimerList->next != __osTimerList) {
+		while (TRUE) {
+			t = __osTimerList->next;
+			if (t == __osTimerList) {
+				__osSetCompare(0);
+				__osTimerCounter = 0;
+				break;
+			}
+			
+			count = osGetCount();
+			elapsed_cycles = count - __osTimerCounter;
+			__osTimerCounter = count;
+
+			if (elapsed_cycles < t->value)
+			{
+				t->value -= elapsed_cycles;
+				__osSetTimerIntr(t->value);
+				break;
+			} else {
+				t->prev->next = t->next;
+				t->next->prev = t->prev;
+				t->next = NULL;
+				t->prev = NULL;
+				
+				if (t->mq != NULL) {
+					osSendMesg(t->mq, t->msg, OS_MESG_NOBLOCK);
+				}
+
+				if (t->interval != 0) {
+					t->value = t->interval;
+					__osInsertTimer(t);
+				}
+			}
+		}
+	}
+}
+
+void __osSetTimerIntr(OSTime tim) {
+	OSTime NewTime;
+	u32 savedMask;
+
+	if (tim < 468) {
+		tim = 468;
+	}
+
+	savedMask = __osDisableInt();
+	__osTimerCounter = osGetCount();
+	NewTime = __osTimerCounter + tim;
+	__osSetCompare(NewTime);
+	__osRestoreInt(savedMask);
+}
+
+OSTime __osInsertTimer(OSTimer *t) {
+	OSTimer *timep;
+	OSTime tim;
+	u32 savedMask;
+	savedMask = __osDisableInt();
+	
+	timep = __osTimerList->next;
+	tim = t->value;
+	
+	while (timep != __osTimerList && tim > timep->value) {
+		tim -= timep->value;
+		timep = timep->next;
+	}
+
+	t->value = tim;
+	
+	if (timep != __osTimerList) {
+		timep->value -= tim;
+	}
+	
+	t->next = timep;
+	t->prev = timep->prev;
+	timep->prev->next = t;
+	timep->prev = t;
+	__osRestoreInt(savedMask);
+	return tim;
+}
diff --git a/src/os/virtualtophysical.c b/src/os/virtualtophysical.c
new file mode 100644
index 0000000..5cf9e86
--- /dev/null
+++ b/src/os/virtualtophysical.c
@@ -0,0 +1,13 @@
+#include "PR/os_internal.h"
+#include "PR/R4300.h"
+#include "osint.h"
+
+u32 osVirtualToPhysical(void *addr) {
+    if (IS_KSEG0(addr)) {
+        return K0_TO_PHYS(addr);
+    } else if (IS_KSEG1(addr)) {
+        return K1_TO_PHYS(addr);
+    } else {
+        return __osProbeTLB(addr);
+    }
+}
diff --git a/src/os/yieldthread.c b/src/os/yieldthread.c
new file mode 100644
index 0000000..f4ed7c5
--- /dev/null
+++ b/src/os/yieldthread.c
@@ -0,0 +1,10 @@
+#include "PR/os_internal.h"
+#include "osint.h"
+
+void osYieldThread(void) {
+    register u32 saveMask = __osDisableInt();
+    
+    __osRunningThread->state = OS_STATE_RUNNABLE;
+    __osEnqueueAndYield(&__osRunQueue);
+    __osRestoreInt(saveMask);
+}