/**

  * $Id$

  * 

  * 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 <setjmp.h>

 #include <assert.h>

 #include "lxdream.h"

 #include "dreamcast.h"

 #include "cpu.h"

 #include "mem.h"

 #include "clock.h"

 #include "eventq.h"

 #include "syscall.h"

 #include "sh4/intc.h"

 #include "sh4/mmu.h"

 #include "sh4/sh4core.h"

 #include "sh4/sh4dasm.h"

 #include "sh4/sh4mmio.h"

 #include "sh4/sh4stat.h"

 #include "sh4/sh4trans.h"

 #include "xlat/xltcache.h"

 #ifndef M_PI

 #define M_PI        3.14159265358979323846264338327950288

 #endif

 void sh4_init( void );

 void sh4_poweron_reset( void );

 void sh4_start( void );

 void sh4_stop( void );

 void sh4_save_state( FILE *f );

 int sh4_load_state( FILE *f );

 size_t sh4_debug_read_phys( unsigned char *buf, uint32_t addr, size_t length );

 size_t sh4_debug_write_phys( uint32_t addr, unsigned char *buf, size_t length );

 size_t sh4_debug_read_vma( unsigned char *buf, uint32_t addr, size_t length );

 size_t sh4_debug_write_vma( uint32_t addr, unsigned char *buf, size_t length );

 uint32_t sh4_run_slice( uint32_t );

 /* Note: this must match GDB's ordering */

 const struct reg_desc_struct sh4_reg_map[] = 

   { {"R0", REG_TYPE_INT, &sh4r.r[0]}, {"R1", REG_TYPE_INT, &sh4r.r[1]},

     {"R2", REG_TYPE_INT, &sh4r.r[2]}, {"R3", REG_TYPE_INT, &sh4r.r[3]},

     {"R4", REG_TYPE_INT, &sh4r.r[4]}, {"R5", REG_TYPE_INT, &sh4r.r[5]},

     {"R6", REG_TYPE_INT, &sh4r.r[6]}, {"R7", REG_TYPE_INT, &sh4r.r[7]},

     {"R8", REG_TYPE_INT, &sh4r.r[8]}, {"R9", REG_TYPE_INT, &sh4r.r[9]},

     {"R10",REG_TYPE_INT, &sh4r.r[10]}, {"R11",REG_TYPE_INT, &sh4r.r[11]},

     {"R12",REG_TYPE_INT, &sh4r.r[12]}, {"R13",REG_TYPE_INT, &sh4r.r[13]},

     {"R14",REG_TYPE_INT, &sh4r.r[14]}, {"R15",REG_TYPE_INT, &sh4r.r[15]},

     {"PC", REG_TYPE_INT, &sh4r.pc}, {"PR", REG_TYPE_INT, &sh4r.pr},

     {"GBR", REG_TYPE_INT, &sh4r.gbr}, {"VBR",REG_TYPE_INT, &sh4r.vbr}, 

     {"MACH",REG_TYPE_INT, ((uint32_t *)&sh4r.mac)+1}, {"MACL",REG_TYPE_INT, &sh4r.mac},

     {"SR", REG_TYPE_INT, &sh4r.sr},

     {"FPUL", REG_TYPE_INT, &sh4r.fpul.i}, {"FPSCR", REG_TYPE_INT, &sh4r.fpscr},

     {"FR0", REG_TYPE_FLOAT, &sh4r.fr[0][1] },{"FR1", REG_TYPE_FLOAT, &sh4r.fr[0][0]},

     {"FR2", REG_TYPE_FLOAT, &sh4r.fr[0][3] },{"FR3", REG_TYPE_FLOAT, &sh4r.fr[0][2]},

     {"FR4", REG_TYPE_FLOAT, &sh4r.fr[0][5] },{"FR5", REG_TYPE_FLOAT, &sh4r.fr[0][4]},

     {"FR6", REG_TYPE_FLOAT, &sh4r.fr[0][7] },{"FR7", REG_TYPE_FLOAT, &sh4r.fr[0][6]},

     {"FR8", REG_TYPE_FLOAT, &sh4r.fr[0][9] },{"FR9", REG_TYPE_FLOAT, &sh4r.fr[0][8]},

     {"FR10", REG_TYPE_FLOAT, &sh4r.fr[0][11] },{"FR11", REG_TYPE_FLOAT, &sh4r.fr[0][10]},

     {"FR12", REG_TYPE_FLOAT, &sh4r.fr[0][13] },{"FR13", REG_TYPE_FLOAT, &sh4r.fr[0][12]},

     {"FR14", REG_TYPE_FLOAT, &sh4r.fr[0][15] },{"FR15", REG_TYPE_FLOAT, &sh4r.fr[0][14]},

     {"SSR",REG_TYPE_INT, &sh4r.ssr}, {"SPC", REG_TYPE_INT, &sh4r.spc},

     {"R0B0", REG_TYPE_INT, NULL}, {"R1B0", REG_TYPE_INT, NULL},

     {"R2B0", REG_TYPE_INT, NULL}, {"R3B0", REG_TYPE_INT, NULL},

     {"R4B0", REG_TYPE_INT, NULL}, {"R5B0", REG_TYPE_INT, NULL},

     {"R6B0", REG_TYPE_INT, NULL}, {"R7B0", REG_TYPE_INT, NULL},

     {"R0B1", REG_TYPE_INT, NULL}, {"R1B1", REG_TYPE_INT, NULL},

     {"R2B1", REG_TYPE_INT, NULL}, {"R3B1", REG_TYPE_INT, NULL},

     {"R4B1", REG_TYPE_INT, NULL}, {"R5B1", REG_TYPE_INT, NULL},

     {"R6B1", REG_TYPE_INT, NULL}, {"R7B1", REG_TYPE_INT, NULL},

     {"SGR",REG_TYPE_INT, &sh4r.sgr}, {"DBR", REG_TYPE_INT, &sh4r.dbr},

     {"XF0", REG_TYPE_FLOAT, &sh4r.fr[1][1] },{"XF1", REG_TYPE_FLOAT, &sh4r.fr[1][0]},

     {"XF2", REG_TYPE_FLOAT, &sh4r.fr[1][3] },{"XF3", REG_TYPE_FLOAT, &sh4r.fr[1][2]},

     {"XF4", REG_TYPE_FLOAT, &sh4r.fr[1][5] },{"XF5", REG_TYPE_FLOAT, &sh4r.fr[1][4]},

     {"XF6", REG_TYPE_FLOAT, &sh4r.fr[1][7] },{"XF7", REG_TYPE_FLOAT, &sh4r.fr[1][6]},

     {"XF8", REG_TYPE_FLOAT, &sh4r.fr[1][9] },{"XF9", REG_TYPE_FLOAT, &sh4r.fr[1][8]},

     {"XF10", REG_TYPE_FLOAT, &sh4r.fr[1][11] },{"XF11", REG_TYPE_FLOAT, &sh4r.fr[1][10]},

     {"XF12", REG_TYPE_FLOAT, &sh4r.fr[1][13] },{"XF13", REG_TYPE_FLOAT, &sh4r.fr[1][12]},

     {"XF14", REG_TYPE_FLOAT, &sh4r.fr[1][15] },{"XF15", REG_TYPE_FLOAT, &sh4r.fr[1][14]},

     {NULL, 0, NULL} };

 void *sh4_get_register( int reg )

 {

     if( reg < 0 || reg >= 94 ) {

         return NULL;

     } else if( reg < 43 ) {

         return sh4_reg_map[reg].value;

     } else if( reg < 51 ) {

         /* r0b0..r7b0 */

         if( (sh4r.sr & SR_MDRB) == SR_MDRB ) {

             /* bank 1 is primary */

             return &sh4r.r_bank[reg-43];

         } else {

             return &sh4r.r[reg-43];

         }

     } else if( reg < 59 ) {

         /* r0b1..r7b1 */

         if( (sh4r.sr & SR_MDRB) == SR_MDRB ) {

             /* bank 1 is primary */

             return &sh4r.r[reg-43];

         } else {

             return &sh4r.r_bank[reg-43];

         }

     } else {

         return NULL; /* not supported at the moment */

     }

 }

 const struct cpu_desc_struct sh4_cpu_desc = 

     { "SH4", sh4_disasm_instruction, sh4_get_register, sh4_has_page,

             sh4_debug_read_phys, sh4_debug_write_phys, sh4_debug_read_vma, sh4_debug_write_vma,

             sh4_execute_instruction, 

       sh4_set_breakpoint, sh4_clear_breakpoint, sh4_get_breakpoint, 2,

       (char *)&sh4r, sizeof(sh4r), sh4_reg_map, 23, 59,

       &sh4r.pc };

 struct dreamcast_module sh4_module = { "SH4", sh4_init, sh4_poweron_reset, 

         sh4_start, sh4_run_slice, sh4_stop,

         sh4_save_state, sh4_load_state };

 struct sh4_registers sh4r __attribute__((aligned(16)));

 struct breakpoint_struct sh4_breakpoints[MAX_BREAKPOINTS];

 int sh4_breakpoint_count = 0;

 gboolean sh4_starting = FALSE;

 static gboolean sh4_use_translator = FALSE;

 static jmp_buf sh4_exit_jmp_buf;

 static gboolean sh4_running = FALSE;

 struct sh4_icache_struct sh4_icache = { NULL, -1, -1, 0 };

 /* At the moment this is a dummy event to mark the end of the

  * timeslice

  */

 void sh4_dummy_event(int eventid)

 {

 }

 void sh4_set_core( sh4core_t core )

 {

     // No-op if the translator was not built

 #ifdef SH4_TRANSLATOR

     if( core != SH4_INTERPRET ) {

         sh4_translate_init();

         sh4_use_translator = TRUE;

         if( core == SH4_SHADOW ) {

             sh4_shadow_init();

         }

     } else {

         sh4_use_translator = FALSE;

     }

 #endif

 }

 gboolean sh4_translate_is_enabled()

 {

     return sh4_use_translator;

 }

 void sh4_init(void)

 {

     register_io_regions( mmio_list_sh4mmio );

     register_event_callback( EVENT_ENDTIMESLICE, sh4_dummy_event );

     MMU_init();

     TMU_init();

     xlat_cache_init();

     sh4_poweron_reset();

 #ifdef ENABLE_SH4STATS

     sh4_stats_reset();

 #endif

 }

 void sh4_start(void)

 {

     sh4_starting = TRUE;

 }

 void sh4_poweron_reset(void)

 {

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

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

     if(	sh4_use_translator ) {

         xlat_flush_cache();

     }

     /* 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;

     sh4_write_sr(0x700000F0);

     /* 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();

     PMM_reset();

     TMU_reset();

     SCIF_reset();

     CCN_reset();

     MMU_reset();

 }

 void sh4_stop(void)

 {

     if(	sh4_use_translator ) {

         /* 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;

         if( sh4_translate_get_profile_blocks() ) {

             sh4_translate_dump_cache_by_activity(30);

         }

     }

 }

 /**

  * Execute a timeslice using translated code only (ie translate/execute loop)

  */

 uint32_t sh4_run_slice( uint32_t nanosecs ) 

 {

     sh4r.slice_cycle = 0;

     /* Setup for sudden vm exits */

     switch( setjmp(sh4_exit_jmp_buf) ) {

     case CORE_EXIT_BREAKPOINT:

         sh4_clear_breakpoint( sh4r.pc, BREAK_ONESHOT );

         /* fallthrough */

     case CORE_EXIT_HALT:

         if( sh4r.sh4_state != SH4_STATE_STANDBY ) {

             TMU_run_slice( sh4r.slice_cycle );

             SCIF_run_slice( sh4r.slice_cycle );

             PMM_run_slice( sh4r.slice_cycle );

             dreamcast_stop();

             return sh4r.slice_cycle;

         }

     case CORE_EXIT_SYSRESET:

         dreamcast_reset();

         break;

     case CORE_EXIT_SLEEP:

         break;  

     case CORE_EXIT_FLUSH_ICACHE:

         xlat_flush_cache();

         break;

     }

     if( sh4r.sh4_state != SH4_STATE_RUNNING ) {

         sh4_sleep_run_slice(nanosecs);

     } else {

         sh4_running = TRUE;

         /* Execute the core's real slice */

 #ifdef SH4_TRANSLATOR

         if( sh4_use_translator ) {

             sh4_translate_run_slice(nanosecs);

         } else {

             sh4_emulate_run_slice(nanosecs);

         }

 #else

         sh4_emulate_run_slice(nanosecs);

 #endif

     }

     /* And finish off the peripherals afterwards */

     sh4_running = FALSE;

     sh4_starting = FALSE;

     sh4r.slice_cycle = nanosecs;

     if( sh4r.sh4_state != SH4_STATE_STANDBY ) {

         TMU_run_slice( nanosecs );

         SCIF_run_slice( nanosecs );

         PMM_run_slice( sh4r.slice_cycle );

     }

     return nanosecs;   

 }

 void sh4_core_exit( int exit_code )

 {

     if( sh4_running ) {

 #ifdef SH4_TRANSLATOR

         if( sh4_use_translator ) {

             if( exit_code == CORE_EXIT_EXCEPTION ) {

                 sh4_translate_exception_exit_recover();

             } else {

                 sh4_translate_exit_recover();

             }

         }

 #endif

         if( exit_code != CORE_EXIT_EXCEPTION &&

             exit_code != CORE_EXIT_BREAKPOINT ) {

             sh4_finalize_instruction();

         }

         // longjmp back into sh4_run_slice

         sh4_running = FALSE;

         longjmp(sh4_exit_jmp_buf, exit_code);

     }

 }

 void sh4_save_state( FILE *f )

 {

     if(	sh4_use_translator ) {

         /* 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, offsetof(struct sh4_registers, xlat_sh4_mode), 1, f );

     MMU_save_state( f );

     CCN_save_state( f );

     PMM_save_state( f );

     INTC_save_state( f );

     TMU_save_state( f );

     SCIF_save_state( f );

 }

 int sh4_load_state( FILE * f )

 {

     if(	sh4_use_translator ) {

         xlat_flush_cache();

     }

     fread( &sh4r, offsetof(struct sh4_registers, xlat_sh4_mode), 1, f );

     sh4r.xlat_sh4_mode = (sh4r.sr & SR_MD) | (sh4r.fpscr & (FPSCR_SZ|FPSCR_PR));

     MMU_load_state( f );

     CCN_load_state( f );

     PMM_load_state( f );

     INTC_load_state( f );

     TMU_load_state( f );

     return SCIF_load_state( f );

 }

 void sh4_set_breakpoint( uint32_t pc, breakpoint_type_t type )

 {

     sh4_breakpoints[sh4_breakpoint_count].address = pc;

     sh4_breakpoints[sh4_breakpoint_count].type = type;

     if( sh4_use_translator ) {

         xlat_invalidate_word( pc );

     }

     sh4_breakpoint_count++;

 }

 gboolean sh4_clear_breakpoint( uint32_t pc, breakpoint_type_t 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;

             }

             if( sh4_use_translator ) {

                 xlat_invalidate_word( pc );

             }

             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;

 }

 void sh4_set_event_pending( uint32_t cycles )

 {

     sh4r.event_pending = cycles;

 }

 /**

  * Dump all SH4 core information for crash-dump purposes

  */

 void sh4_crashdump()

 {

     cpu_print_registers( stderr, &sh4_cpu_desc );

 #ifdef SH4_TRANSLATOR

     if( sh4_use_translator ) {

         sh4_translate_crashdump();

     } /* Nothing really to print for emu core */

 #endif

 }

 /******************************* 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 FASTCALL sh4_switch_fr_banks()

 {

     int i;

     for( i=0; i<16; i++ ) {

         float tmp = sh4r.fr[0][i];

         sh4r.fr[0][i] = sh4r.fr[1][i];

         sh4r.fr[1][i] = tmp;

     }

 }

 void FASTCALL sh4_write_sr( uint32_t newval )

 {

     int oldbank = (sh4r.sr&SR_MDRB) == SR_MDRB;

     int newbank = (newval&SR_MDRB) == SR_MDRB;

     if( oldbank != newbank )

         sh4_switch_banks();

     sh4r.sr = newval & SR_MASK;

     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;

     sh4r.xlat_sh4_mode = (sh4r.sr & SR_MD) | (sh4r.fpscr & (FPSCR_SZ|FPSCR_PR));

     intc_mask_changed();

 }

 void FASTCALL sh4_write_fpscr( uint32_t newval )

 {

     if( (sh4r.fpscr ^ newval) & FPSCR_FR ) {

         sh4_switch_fr_banks();

     }

     sh4r.fpscr = newval & FPSCR_MASK;

     sh4r.xlat_sh4_mode = (sh4r.sr & SR_MD) | (sh4r.fpscr & (FPSCR_SZ|FPSCR_PR));

 }

 uint32_t FASTCALL 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;

 }

 /**

  * Raise a CPU reset exception with the specified exception code.

  */

 void FASTCALL sh4_raise_reset( int code )

 {

     MMIO_WRITE(MMU,EXPEVT,code);

     sh4r.vbr = 0x00000000;

     sh4r.pc = 0xA0000000;

     sh4r.new_pc = sh4r.pc + 2;

     sh4r.in_delay_slot = 0;

     sh4_write_sr( (sh4r.sr|SR_MD|SR_BL|SR_RB|SR_IMASK)&(~SR_FD) );

     /* Peripheral manual reset (FIXME: incomplete) */

     INTC_reset();

     SCIF_reset();

     MMU_reset();

 }

 void FASTCALL sh4_raise_tlb_multihit( sh4vma_t vpn )

 {

     MMIO_WRITE( MMU, TEA, vpn );

     MMIO_WRITE( MMU, PTEH, ((MMIO_READ(MMU, PTEH) & 0x000003FF) | (vpn&0xFFFFFC00)) );

     sh4_raise_reset( EXC_TLB_MULTI_HIT );

 }

 /**

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

  * (NOT for TRAPA or TLB exceptions)

  */

 void FASTCALL sh4_raise_exception( int code )

 {

     if( sh4r.sr & SR_BL ) {

         sh4_raise_reset( EXC_MANUAL_RESET );

     } else {

         sh4r.spc = sh4r.pc;

         sh4r.ssr = sh4_read_sr();

         sh4r.sgr = sh4r.r[15];

         MMIO_WRITE(MMU,EXPEVT, code);

         sh4r.pc = sh4r.vbr + EXV_EXCEPTION;

         sh4r.new_pc = sh4r.pc + 2;

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

         sh4r.in_delay_slot = 0;

     }

 }

 void FASTCALL sh4_raise_trap( int trap )

 {

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

     MMIO_WRITE( MMU, EXPEVT, EXC_TRAP );

     sh4r.spc = sh4r.pc;

     sh4r.ssr = sh4_read_sr();

     sh4r.sgr = sh4r.r[15];

     sh4r.pc = sh4r.vbr + EXV_EXCEPTION;

     sh4r.new_pc = sh4r.pc + 2;

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

     sh4r.in_delay_slot = 0;

 }

 void FASTCALL sh4_raise_tlb_exception( int code, sh4vma_t vpn )

 {

     MMIO_WRITE( MMU, TEA, vpn );

     MMIO_WRITE( MMU, PTEH, ((MMIO_READ(MMU, PTEH) & 0x000003FF) | (vpn&0xFFFFFC00)) );

     MMIO_WRITE( MMU, EXPEVT, code );

     sh4r.spc = sh4r.pc;

     sh4r.ssr = sh4_read_sr();

     sh4r.sgr = sh4r.r[15];

     sh4r.pc = sh4r.vbr + EXV_TLBMISS;

     sh4r.new_pc = sh4r.pc + 2;

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

     sh4r.in_delay_slot = 0;

 }

 void FASTCALL sh4_accept_interrupt( void )

 {

     uint32_t code = intc_accept_interrupt();

     MMIO_WRITE( MMU, INTEVT, code );

     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 );

     sh4r.pc = sh4r.vbr + 0x600;

     sh4r.new_pc = sh4r.pc + 2;

     sh4r.in_delay_slot = 0;

 }

 void FASTCALL 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 FASTCALL sh4_fsca( uint32_t anglei, float *fr )

 {

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

     *fr++ = cosf(angle);

     *fr = sinf(angle);

 }

 /**

  * Enter sleep mode (eg by executing a SLEEP instruction).

  * Sets sh4_state appropriately and ensures any stopping peripheral modules

  * are up to date.

  */

 void FASTCALL sh4_sleep(void)

 {

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

         sh4r.sh4_state = SH4_STATE_STANDBY;

         /* Bring all running peripheral modules up to date, and then halt them. */

         TMU_run_slice( sh4r.slice_cycle );

         SCIF_run_slice( sh4r.slice_cycle );

         PMM_run_slice( sh4r.slice_cycle );

     } else {

         if( MMIO_READ( CPG, STBCR2 ) & 0x80 ) {

             sh4r.sh4_state = SH4_STATE_DEEP_SLEEP;

             /* Halt DMAC but other peripherals still running */

         } else {

             sh4r.sh4_state = SH4_STATE_SLEEP;

         }

     }

     sh4_core_exit( CORE_EXIT_SLEEP );

 }

 /**

  * Wakeup following sleep mode (IRQ or reset). Sets state back to running,

  * and restarts any peripheral devices that were stopped.

  */

 void sh4_wakeup(void)

 {

     switch( sh4r.sh4_state ) {

     case SH4_STATE_STANDBY:

         break;

     case SH4_STATE_DEEP_SLEEP:

         break;

     case SH4_STATE_SLEEP:

         break;

     }

     sh4r.sh4_state = SH4_STATE_RUNNING;

 }

 /**

  * Run a time slice (or portion of a timeslice) while the SH4 is sleeping.

  * Returns when either the SH4 wakes up (interrupt received) or the end of

  * the slice is reached. Updates sh4.slice_cycle with the exit time and

  * returns the same value.

  */

 uint32_t sh4_sleep_run_slice( uint32_t nanosecs )

 {

     assert( sh4r.sh4_state != SH4_STATE_RUNNING );

     while( sh4r.event_pending < nanosecs ) {

         sh4r.slice_cycle = sh4r.event_pending;

         if( sh4r.event_types & PENDING_EVENT ) {

             event_execute();

         }

         if( sh4r.event_types & PENDING_IRQ ) {

             sh4_wakeup();

             return sh4r.slice_cycle;

         }

     }

     if( sh4r.slice_cycle < nanosecs )

         sh4r.slice_cycle = nanosecs;

     return sh4r.slice_cycle;

 }

 /**

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

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

  */

 void FASTCALL sh4_ftrv( float *target )

 {

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

     target[1] = sh4r.fr[1][1] * fv[0] + sh4r.fr[1][5]*fv[1] +

     sh4r.fr[1][9]*fv[2] + sh4r.fr[1][13]*fv[3];

     target[0] = sh4r.fr[1][0] * fv[0] + sh4r.fr[1][4]*fv[1] +

     sh4r.fr[1][8]*fv[2] + sh4r.fr[1][12]*fv[3];

     target[3] = sh4r.fr[1][3] * fv[0] + sh4r.fr[1][7]*fv[1] +

     sh4r.fr[1][11]*fv[2] + sh4r.fr[1][15]*fv[3];

     target[2] = sh4r.fr[1][2] * fv[0] + sh4r.fr[1][6]*fv[1] +

     sh4r.fr[1][10]*fv[2] + sh4r.fr[1][14]*fv[3];

 }

 gboolean sh4_has_page( sh4vma_t vma )

 {

     sh4addr_t addr = mmu_vma_to_phys_disasm(vma);

     return addr != MMU_VMA_ERROR && mem_has_page(addr);

 }

 void sh4_handle_pending_events() {

     if( sh4r.event_types & PENDING_EVENT ) {

         event_execute();

     }

     /* Eventq execute may (quite likely) deliver an immediate IRQ */

     if( sh4r.event_types & PENDING_IRQ ) {

         sh4_accept_interrupt();

     }

 }

 /**

  * Go through ext_address_space page by page

  */

 size_t sh4_debug_read_phys( unsigned char *buf, uint32_t addr, size_t length )

 {

     /* Quick and very dirty */

     unsigned char *region = mem_get_region(addr);

     if( region == NULL ) {

         memset( buf, 0, length );

     } else {

         memcpy( buf, region, length );

     }

     return length;

 }

 size_t sh4_debug_write_phys( uint32_t addr, unsigned char *buf, size_t length )

 {

     unsigned char *region = mem_get_region(addr);

     if( region != NULL ) {

         memcpy( region, buf, length );

     }

     return length;

 }

 /**

  * Read virtual memory - for now just go 1K at a time 

  */

 size_t sh4_debug_read_vma( unsigned char *buf, uint32_t addr, size_t length )

 {

     if( IS_TLB_ENABLED() ) {

         size_t read_len = 0;

         while( length > 0 ) {

             sh4addr_t phys = mmu_vma_to_phys_disasm(addr);

             if( phys == MMU_VMA_ERROR )

                 break;

             int next_len = 1024 - (phys&0x000003FF);

             if( next_len >= length ) {

                 next_len = length;

             }

             sh4_debug_read_phys( buf, phys, length );

             buf += next_len;

             addr += next_len;

             read_len += next_len; 

             length -= next_len;

         }

         return read_len;

     } else {

         return sh4_debug_read_phys( buf, addr, length );

     }

 }

 size_t sh4_debug_write_vma( uint32_t addr, unsigned char *buf, size_t length )

 {

     if( IS_TLB_ENABLED() ) {

         size_t read_len = 0;

         while( length > 0 ) {

             sh4addr_t phys = mmu_vma_to_phys_disasm(addr);

             if( phys == MMU_VMA_ERROR )

                 break;

             int next_len = 1024 - (phys&0x000003FF);

             if( next_len >= length ) {

                 next_len = length;

             }

             sh4_debug_write_phys( phys, buf, length );

             buf += next_len;

             addr += next_len;

             read_len += next_len; 

             length -= next_len;

         }

         return read_len;

     } else {

         return sh4_debug_write_phys( addr, buf, length );

     }

 }