/**

  * $Id: sh4.c,v 1.3 2007-10-01 11:51:25 nkeynes Exp $

  * 

  * SH4 parent module for all CPU modes and SH4 peripheral

  * modules.

  *

  * Copyright (c) 2005 Nathan Keynes.

  *

  * This program is free software; you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation; either version 2 of the License, or

  * (at your option) any later version.

  *

  * This program is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  * GNU General Public License for more details.

  */

 #define MODULE sh4_module

 #include <math.h>

 #include "dream.h"

 #include "sh4/sh4core.h"

 #include "sh4/sh4mmio.h"

 #include "sh4/intc.h"

 #include "mem.h"

 #include "clock.h"

 #include "syscall.h"

 #define EXV_EXCEPTION    0x100  /* General exception vector */

 #define EXV_TLBMISS      0x400  /* TLB-miss exception vector */

 #define EXV_INTERRUPT    0x600  /* External interrupt vector */

 void sh4_init( void );

 void sh4_reset( void );

 void sh4_start( void );

 void sh4_stop( void );

 void sh4_save_state( FILE *f );

 int sh4_load_state( FILE *f );

 uint32_t sh4_run_slice( uint32_t );

 uint32_t sh4_xlat_run_slice( uint32_t );

 struct dreamcast_module sh4_module = { "SH4", sh4_init, sh4_reset, 

 				       NULL, sh4_run_slice, sh4_stop,

 				       sh4_save_state, sh4_load_state };

 struct sh4_registers sh4r;

 struct breakpoint_struct sh4_breakpoints[MAX_BREAKPOINTS];

 int sh4_breakpoint_count = 0;

 void sh4_set_use_xlat( gboolean use )

 {

     if( use ) {

 	xlat_cache_init();

 	sh4_x86_init();

 	sh4_module.run_time_slice = sh4_xlat_run_slice;

     } else {

 	sh4_module.run_time_slice = sh4_run_slice;

     }

 }

 void sh4_init(void)

 {

     register_io_regions( mmio_list_sh4mmio );

     MMU_init();

     sh4_reset();

 }

 void sh4_reset(void)

 {

     /* zero everything out, for the sake of having a consistent state. */

     memset( &sh4r, 0, sizeof(sh4r) );

     /* Resume running if we were halted */

     sh4r.sh4_state = SH4_STATE_RUNNING;

     sh4r.pc    = 0xA0000000;

     sh4r.new_pc= 0xA0000002;

     sh4r.vbr   = 0x00000000;

     sh4r.fpscr = 0x00040001;

     sh4r.sr    = 0x700000F0;

     sh4r.fr_bank = &sh4r.fr[0][0];

     /* Mem reset will do this, but if we want to reset _just_ the SH4... */

     MMIO_WRITE( MMU, EXPEVT, EXC_POWER_RESET );

     /* Peripheral modules */

     CPG_reset();

     INTC_reset();

     MMU_reset();

     TMU_reset();

     SCIF_reset();

     sh4_stats_reset();

 }

 void sh4_stop(void)

 {

 }

 void sh4_save_state( FILE *f )

 {

     if(	sh4_module.run_time_slice == sh4_xlat_run_slice ) {

 	/* If we were running with the translator, update new_pc and in_delay_slot */

 	sh4r.new_pc = sh4r.pc+2;

 	sh4r.in_delay_slot = FALSE;

     }

     fwrite( &sh4r, sizeof(sh4r), 1, f );

     MMU_save_state( f );

     INTC_save_state( f );

     TMU_save_state( f );

     SCIF_save_state( f );

 }

 int sh4_load_state( FILE * f )

 {

     fread( &sh4r, sizeof(sh4r), 1, f );

     sh4r.fr_bank = &sh4r.fr[(sh4r.fpscr&FPSCR_FR)>>21][0]; // Fixup internal FR pointer

     MMU_load_state( f );

     INTC_load_state( f );

     TMU_load_state( f );

     return SCIF_load_state( f );

 }

 void sh4_set_breakpoint( uint32_t pc, int type )

 {

     sh4_breakpoints[sh4_breakpoint_count].address = pc;

     sh4_breakpoints[sh4_breakpoint_count].type = type;

     sh4_breakpoint_count++;

 }

 gboolean sh4_clear_breakpoint( uint32_t pc, int type )

 {

     int i;

     for( i=0; i<sh4_breakpoint_count; i++ ) {

 	if( sh4_breakpoints[i].address == pc && 

 	    sh4_breakpoints[i].type == type ) {

 	    while( ++i < sh4_breakpoint_count ) {

 		sh4_breakpoints[i-1].address = sh4_breakpoints[i].address;

 		sh4_breakpoints[i-1].type = sh4_breakpoints[i].type;

 	    }

 	    sh4_breakpoint_count--;

 	    return TRUE;

 	}

     }

     return FALSE;

 }

 int sh4_get_breakpoint( uint32_t pc )

 {

     int i;

     for( i=0; i<sh4_breakpoint_count; i++ ) {

 	if( sh4_breakpoints[i].address == pc )

 	    return sh4_breakpoints[i].type;

     }

     return 0;

 }

 void sh4_set_pc( int pc )

 {

     sh4r.pc = pc;

     sh4r.new_pc = pc+2;

 }

 /******************************* Support methods ***************************/

 static void sh4_switch_banks( )

 {

     uint32_t tmp[8];

     memcpy( tmp, sh4r.r, sizeof(uint32_t)*8 );

     memcpy( sh4r.r, sh4r.r_bank, sizeof(uint32_t)*8 );

     memcpy( sh4r.r_bank, tmp, sizeof(uint32_t)*8 );

 }

 void sh4_write_sr( uint32_t newval )

 {

     if( (newval ^ sh4r.sr) & SR_RB )

         sh4_switch_banks();

     sh4r.sr = newval;

     sh4r.t = (newval&SR_T) ? 1 : 0;

     sh4r.s = (newval&SR_S) ? 1 : 0;

     sh4r.m = (newval&SR_M) ? 1 : 0;

     sh4r.q = (newval&SR_Q) ? 1 : 0;

     intc_mask_changed();

 }

 uint32_t sh4_read_sr( void )

 {

     /* synchronize sh4r.sr with the various bitflags */

     sh4r.sr &= SR_MQSTMASK;

     if( sh4r.t ) sh4r.sr |= SR_T;

     if( sh4r.s ) sh4r.sr |= SR_S;

     if( sh4r.m ) sh4r.sr |= SR_M;

     if( sh4r.q ) sh4r.sr |= SR_Q;

     return sh4r.sr;

 }

 #define RAISE( x, v ) do{			\

     if( sh4r.vbr == 0 ) { \

         ERROR( "%08X: VBR not initialized while raising exception %03X, halting", sh4r.pc, x ); \

         dreamcast_stop(); return FALSE;	\

     } else { \

         sh4r.spc = sh4r.pc;	\

         sh4r.ssr = sh4_read_sr(); \

         sh4r.sgr = sh4r.r[15]; \

         MMIO_WRITE(MMU,EXPEVT,x); \

         sh4r.pc = sh4r.vbr + v; \

         sh4r.new_pc = sh4r.pc + 2; \

         sh4_write_sr( sh4r.ssr |SR_MD|SR_BL|SR_RB ); \

 	if( sh4r.in_delay_slot ) { \

 	    sh4r.in_delay_slot = 0; \

 	    sh4r.spc -= 2; \

 	} \

     } \

     return TRUE; } while(0)

 /**

  * Raise a general CPU exception for the specified exception code.

  * (NOT for TRAPA or TLB exceptions)

  */

 gboolean sh4_raise_exception( int code )

 {

     RAISE( code, EXV_EXCEPTION );

 }

 gboolean sh4_raise_trap( int trap )

 {

     MMIO_WRITE( MMU, TRA, trap<<2 );

     return sh4_raise_exception( EXC_TRAP );

 }

 gboolean sh4_raise_slot_exception( int normal_code, int slot_code ) {

     if( sh4r.in_delay_slot ) {

 	return sh4_raise_exception(slot_code);

     } else {

 	return sh4_raise_exception(normal_code);

     }

 }

 gboolean sh4_raise_tlb_exception( int code )

 {

     RAISE( code, EXV_TLBMISS );

 }

 void sh4_accept_interrupt( void )

 {

     uint32_t code = intc_accept_interrupt();

     sh4r.ssr = sh4_read_sr();

     sh4r.spc = sh4r.pc;

     sh4r.sgr = sh4r.r[15];

     sh4_write_sr( sh4r.ssr|SR_BL|SR_MD|SR_RB );

     MMIO_WRITE( MMU, INTEVT, code );

     sh4r.pc = sh4r.vbr + 0x600;

     sh4r.new_pc = sh4r.pc + 2;

     //    WARN( "Accepting interrupt %03X, from %08X => %08X", code, sh4r.spc, sh4r.pc );

 }

 void signsat48( void )

 {

     if( ((int64_t)sh4r.mac) < (int64_t)0xFFFF800000000000LL )

 	sh4r.mac = 0xFFFF800000000000LL;

     else if( ((int64_t)sh4r.mac) > (int64_t)0x00007FFFFFFFFFFFLL )

 	sh4r.mac = 0x00007FFFFFFFFFFFLL;

 }

 void sh4_fsca( uint32_t anglei, float *fr )

 {

     float angle = (((float)(anglei&0xFFFF))/65536.0) * 2 * M_PI;

     *fr++ = cosf(angle);

     *fr = sinf(angle);

 }

 void sh4_sleep(void)

 {

     if( MMIO_READ( CPG, STBCR ) & 0x80 ) {

 	sh4r.sh4_state = SH4_STATE_STANDBY;

     } else {

 	sh4r.sh4_state = SH4_STATE_SLEEP;

     }

 }

 /**

  * Compute the matrix tranform of fv given the matrix xf.

  * Both fv and xf are word-swapped as per the sh4r.fr banks

  */

 void sh4_ftrv( float *target, float *xf )

 {

     float fv[4] = { target[1], target[0], target[3], target[2] };

     target[1] = xf[1] * fv[0] + xf[5]*fv[1] +

 	xf[9]*fv[2] + xf[13]*fv[3];

     target[0] = xf[0] * fv[0] + xf[4]*fv[1] +

 	xf[8]*fv[2] + xf[12]*fv[3];

     target[3] = xf[3] * fv[0] + xf[7]*fv[1] +

 	xf[11]*fv[2] + xf[15]*fv[3];

     target[2] = xf[2] * fv[0] + xf[6]*fv[1] +

 	xf[10]*fv[2] + xf[14]*fv[3];

 }