yuzu/src/core/arm/interpreter/arminit.cpp

/*  arminit.c -- ARMulator initialization:  ARM6 Instruction Emulator.
    Copyright (C) 1994 Advanced RISC Machines Ltd.

    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.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */

#include "core/arm/skyeye_common/armdefs.h"
#include "core/arm/skyeye_common/armemu.h"

/***************************************************************************\
*                 Definitions for the emulator architecture                 *
\***************************************************************************/

void ARMul_EmulateInit();
ARMul_State* ARMul_NewState(ARMul_State* state);
void ARMul_Reset (ARMul_State* state);

unsigned ARMul_MultTable[32] = {
    1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9,
    10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15, 15, 16, 16, 16
};
ARMword ARMul_ImmedTable[4096]; // immediate DP LHS values
char ARMul_BitList[256];        // number of bits in a byte table

/***************************************************************************\
*         Call this routine once to set up the emulator's tables.           *
\***************************************************************************/
void ARMul_EmulateInit()
{
    unsigned int i, j;

    // the values of 12 bit dp rhs's
    for (i = 0; i < 4096; i++) {
        ARMul_ImmedTable[i] = ROTATER (i & 0xffL, (i >> 7L) & 0x1eL);
    }

    // how many bits in LSM
    for (i = 0; i < 256; ARMul_BitList[i++] = 0);
    for (j = 1; j < 256; j <<= 1)
        for (i = 0; i < 256; i++)
            if ((i & j) > 0)
                ARMul_BitList[i]++;

    // you always need 4 times these values
    for (i = 0; i < 256; i++)
        ARMul_BitList[i] *= 4;

}

/***************************************************************************\
*            Returns a new instantiation of the ARMulator's state           *
\***************************************************************************/
ARMul_State* ARMul_NewState(ARMul_State* state)
{
    memset (state, 0, sizeof (ARMul_State));

    state->Emulate = RUN;
    for (unsigned int i = 0; i < 16; i++) {
        state->Reg[i] = 0;
        for (unsigned int j = 0; j < 7; j++)
            state->RegBank[j][i] = 0;
    }
    for (unsigned int i = 0; i < 7; i++)
        state->Spsr[i] = 0;

    state->Mode = USER32MODE;

    state->VectorCatch = 0;
    state->Aborted = false;
    state->Reseted = false;
    state->Inted = 3;
    state->LastInted = 3;

#ifdef ARM61
    state->prog32Sig = LOW;
    state->data32Sig = LOW;
#else
    state->prog32Sig = HIGH;
    state->data32Sig = HIGH;
#endif

    state->lateabtSig = HIGH;
    state->bigendSig = LOW;

    return state;
}

/***************************************************************************\
*       Call this routine to set ARMulator to model a certain processor     *
\***************************************************************************/

void ARMul_SelectProcessor(ARMul_State* state, unsigned properties)
{
    if (properties & ARM_Fix26_Prop) {
        state->prog32Sig = LOW;
        state->data32Sig = LOW;
    } else {
        state->prog32Sig = HIGH;
        state->data32Sig = HIGH;
    }

    state->is_v4     = (properties & (ARM_v4_Prop | ARM_v5_Prop)) != 0;
    state->is_v5     = (properties & ARM_v5_Prop) != 0;
    state->is_v5e    = (properties & ARM_v5e_Prop) != 0;
    state->is_XScale = (properties & ARM_XScale_Prop) != 0;
    state->is_iWMMXt = (properties & ARM_iWMMXt_Prop) != 0;
    state->is_v6     = (properties & ARM_v6_Prop) != 0;
    state->is_ep9312 = (properties & ARM_ep9312_Prop) != 0;
    state->is_pxa27x = (properties & ARM_PXA27X_Prop) != 0;
    state->is_v7     = (properties & ARM_v7_Prop) != 0;

    /* Only initialse the coprocessor support once we
       know what kind of chip we are dealing with.  */
    //ARMul_CoProInit (state);

}

/***************************************************************************\
* Call this routine to set up the initial machine state (or perform a RESET *
\***************************************************************************/
void ARMul_Reset(ARMul_State* state)
{
    state->NextInstr = 0;
    if (state->prog32Sig) {
        state->Reg[15] = 0;
        state->Cpsr = INTBITS | SVC32MODE;
        state->Mode = SVC32MODE;
    } else {
        state->Reg[15] = R15INTBITS | SVC26MODE;
        state->Cpsr = INTBITS | SVC26MODE;
        state->Mode = SVC26MODE;
    }

    state->Bank = SVCBANK;
    FLUSHPIPE;

    state->EndCondition = 0;
    state->ErrorCode = 0;

    state->NresetSig = HIGH;
    state->NfiqSig = HIGH;
    state->NirqSig = HIGH;
    state->NtransSig = (state->Mode & 3) ? HIGH : LOW;
    state->abortSig = LOW;
    state->AbortAddr = 1;

    state->NumInstrs = 0;
}