/**

  * $Id$

  * 

  * 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 "mem.h"

 #include "clock.h"

 #include "eventq.h"

 #include "syscall.h"

 #include "sh4/intc.h"

 #include "sh4/sh4core.h"

 #include "sh4/sh4mmio.h"

 #include "sh4/sh4stat.h"

 #include "sh4/sh4trans.h"

 #include "sh4/xltcache.h"

 void sh4_init( void );

 void sh4_xlat_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, 

         sh4_start, 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;

 sh4ptr_t sh4_main_ram;

 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 };

 void sh4_translate_set_enabled( gboolean use )

 {

     // No-op if the translator was not built

 #ifdef SH4_TRANSLATOR

     xlat_cache_init();

     if( use ) {

         sh4_translate_init();

     }

     sh4_use_translator = use;

 #endif

 }

 gboolean sh4_translate_is_enabled()

 {

     return sh4_use_translator;

 }

 void sh4_init(void)

 {

     register_io_regions( mmio_list_sh4mmio );

     sh4_main_ram = mem_get_region_by_name(MEM_REGION_MAIN);

     MMU_init();

     TMU_init();

     sh4_reset();

 #ifdef ENABLE_SH4STATS

     sh4_stats_reset();

 #endif

 }

 void sh4_start(void)

 {

     sh4_starting = TRUE;

 }

 void sh4_reset(void)

 {

     if(	sh4_use_translator ) {

         xlat_flush_cache();

     }

     /* 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;

     /* 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();

 #ifdef ENABLE_SH4STATS

     sh4_stats_reset();

 #endif

 }

 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;

     }

 }

 /**

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

  */

 uint32_t sh4_run_slice( uint32_t nanosecs ) 

 {

     sh4r.slice_cycle = 0;

     if( sh4r.sh4_state != SH4_STATE_RUNNING ) {

         sh4_sleep_run_slice(nanosecs);

     }

     /* 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 );

             dreamcast_stop();

             return sh4r.slice_cycle;

         }

     case CORE_EXIT_SYSRESET:

         dreamcast_reset();

         break;

     case CORE_EXIT_SLEEP:

         sh4_sleep_run_slice(nanosecs);

         break;  

     case CORE_EXIT_FLUSH_ICACHE:

 #ifdef SH4_TRANSLATOR

         xlat_flush_cache();

 #endif

         break;

     }

     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 );

     }

     return nanosecs;   

 }

 void sh4_core_exit( int exit_code )

 {

     if( sh4_running ) {

 #ifdef SH4_TRANSLATOR

         if( sh4_use_translator ) {

             sh4_translate_exit_recover();

         }

 #endif

         // longjmp back into sh4_run_slice

         sh4_running = FALSE;

         longjmp(sh4_exit_jmp_buf, exit_code);

     }

 }

 void sh4_flush_icache()

 {

 #ifdef SH4_TRANSLATOR

     // FIXME: Special case needs to be generalized

     if( sh4_use_translator ) {

         if( sh4_translate_flush_cache() ) {

             longjmp(sh4_exit_jmp_buf, CORE_EXIT_CONTINUE);

         }

     }

 #endif

 }

 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, 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 )

 {

     if(	sh4_use_translator ) {

         xlat_flush_cache();

     }

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

     MMU_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;

 }

 /******************************* 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_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 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;

     intc_mask_changed();

 }

 void sh4_write_fpscr( uint32_t newval )

 {

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

         sh4_switch_fr_banks();

     }

     sh4r.fpscr = newval & FPSCR_MASK;

 }

 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 ); \

         sh4_core_exit(CORE_EXIT_HALT); 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 );

 }

 /**

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

  */

 gboolean sh4_raise_reset( int code )

 {

     // FIXME: reset modules as per "manual reset"

     sh4_reset();

     MMIO_WRITE(MMU,EXPEVT,code);

     sh4r.vbr = 0;

     sh4r.pc = 0xA0000000;

     sh4r.new_pc = sh4r.pc + 2;

     sh4_write_sr( (sh4r.sr|SR_MD|SR_BL|SR_RB|SR_IMASK)

                   &(~SR_FD) );

     return TRUE;

 }

 gboolean sh4_raise_trap( int trap )

 {

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

     RAISE( EXC_TRAP, EXV_EXCEPTION );

 }

 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);

 }

 /**

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

  * Sets sh4_state appropriately and ensures any stopping peripheral modules

  * are up to date.

  */

 void 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 );

     } 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 )

 {

     int sleep_state = sh4r.sh4_state;

     assert( sleep_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;

         }

     }

     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 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);

 }