/**

 * $Id$

 * 

 * 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 __attribute__((aligned(16)));

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();

    PMM_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 );

            PMM_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 );

        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 ) {

            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 );

    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, sizeof(sh4r), 1, f );

    MMU_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;

}

/******************************* 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;

    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;

}

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;

}

#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 FASTCALL sh4_raise_exception( int code )

{

    RAISE( code, EXV_EXCEPTION );

}

/**

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

 */

gboolean FASTCALL 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 FASTCALL sh4_raise_trap( int trap )

{

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

    RAISE( EXC_TRAP, EXV_EXCEPTION );

}

gboolean FASTCALL 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 FASTCALL sh4_raise_tlb_exception( int code )

{

    RAISE( code, EXV_TLBMISS );

}

void FASTCALL 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 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 )

{

    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 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);

}