/*

 *  CRIS helper routines

 *

 *  Copyright (c) 2007 AXIS Communications

 *  Written by Edgar E. Iglesias

 *

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

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#include <assert.h>

#include "exec.h"

#include "mmu.h"

#include "helper.h"

#define D(x)

#if !defined(CONFIG_USER_ONLY)

#define MMUSUFFIX _mmu

#define SHIFT 0

#include "softmmu_template.h"

#define SHIFT 1

#include "softmmu_template.h"

#define SHIFT 2

#include "softmmu_template.h"

#define SHIFT 3

#include "softmmu_template.h"

/* Try to fill the TLB and return an exception if error. If retaddr is

   NULL, it means that the function was called in C code (i.e. not

   from generated code or from helper.c) */

/* XXX: fix it to restore all registers */

void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)

{

    TranslationBlock *tb;

    CPUState *saved_env;

    unsigned long pc;

    int ret;

    /* XXX: hack to restore env in all cases, even if not called from

       generated code */

    saved_env = env;

    env = cpu_single_env;

    D(fprintf(logfile, "%s pc=%x tpc=%x ra=%x\n", __func__, 

	     env->pc, env->debug1, retaddr));

    ret = cpu_cris_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);

    if (unlikely(ret)) {

        if (retaddr) {

            /* now we have a real cpu fault */

            pc = (unsigned long)retaddr;

            tb = tb_find_pc(pc);

            if (tb) {

                /* the PC is inside the translated code. It means that we have

                   a virtual CPU fault */

                cpu_restore_state(tb, env, pc, NULL);

		/* Evaluate flags after retranslation.  */

                helper_top_evaluate_flags();

            }

        }

        cpu_loop_exit();

    }

    env = saved_env;

}

#endif

void helper_raise_exception(uint32_t index)

{

	env->exception_index = index;

	cpu_loop_exit();

}

void helper_tlb_flush_pid(uint32_t pid)

{

#if !defined(CONFIG_USER_ONLY)

	pid &= 0xff;

	if (pid != (env->pregs[PR_PID] & 0xff))

		cris_mmu_flush_pid(env, env->pregs[PR_PID]);

#endif

}

void helper_spc_write(uint32_t new_spc)

{

#if !defined(CONFIG_USER_ONLY)

	tlb_flush_page(env, env->pregs[PR_SPC]);

	tlb_flush_page(env, new_spc);

#endif

}

void helper_dump(uint32_t a0, uint32_t a1, uint32_t a2)

{

	(fprintf(logfile, "%s: a0=%x a1=%x\n", __func__, a0, a1)); 

}

/* Used by the tlb decoder.  */

#define EXTRACT_FIELD(src, start, end) \

	    (((src) >> start) & ((1 << (end - start + 1)) - 1))

void helper_movl_sreg_reg (uint32_t sreg, uint32_t reg)

{

	uint32_t srs;

	srs = env->pregs[PR_SRS];

	srs &= 3;

	env->sregs[srs][sreg] = env->regs[reg];

#if !defined(CONFIG_USER_ONLY)

	if (srs == 1 || srs == 2) {

		if (sreg == 6) {

			/* Writes to tlb-hi write to mm_cause as a side 

			   effect.  */

			env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];

			env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];

		}

		else if (sreg == 5) {

			uint32_t set;

			uint32_t idx;

			uint32_t lo, hi;

			uint32_t vaddr;

			int tlb_v;

			idx = set = env->sregs[SFR_RW_MM_TLB_SEL];

			set >>= 4;

			set &= 3;

			idx &= 15;

			/* We've just made a write to tlb_lo.  */

			lo = env->sregs[SFR_RW_MM_TLB_LO];

			/* Writes are done via r_mm_cause.  */

			hi = env->sregs[SFR_R_MM_CAUSE];

			vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,

					      13, 31);

			vaddr <<= TARGET_PAGE_BITS;

			tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,

					    3, 3);

			env->tlbsets[srs - 1][set][idx].lo = lo;

			env->tlbsets[srs - 1][set][idx].hi = hi;

			D(fprintf(logfile, 

				  "tlb flush vaddr=%x v=%d pc=%x\n", 

				  vaddr, tlb_v, env->pc));

			tlb_flush_page(env, vaddr);

		}

	}

#endif

}

void helper_movl_reg_sreg (uint32_t reg, uint32_t sreg)

{

	uint32_t srs;

	env->pregs[PR_SRS] &= 3;

	srs = env->pregs[PR_SRS];

#if !defined(CONFIG_USER_ONLY)

	if (srs == 1 || srs == 2)

	{

		uint32_t set;

		uint32_t idx;

		uint32_t lo, hi;

		idx = set = env->sregs[SFR_RW_MM_TLB_SEL];

		set >>= 4;

		set &= 3;

		idx &= 15;

		/* Update the mirror regs.  */

		hi = env->tlbsets[srs - 1][set][idx].hi;

		lo = env->tlbsets[srs - 1][set][idx].lo;

		env->sregs[SFR_RW_MM_TLB_HI] = hi;

		env->sregs[SFR_RW_MM_TLB_LO] = lo;

	}

#endif

	env->regs[reg] = env->sregs[srs][sreg];

}

static void cris_ccs_rshift(CPUState *env)

{

	uint32_t ccs;

	/* Apply the ccs shift.  */

	ccs = env->pregs[PR_CCS];

	ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);

	if (ccs & U_FLAG)

	{

		/* Enter user mode.  */

		env->ksp = env->regs[R_SP];

		env->regs[R_SP] = env->pregs[PR_USP];

	}

	env->pregs[PR_CCS] = ccs;

}

void helper_rfe(void)

{

	int rflag = env->pregs[PR_CCS] & R_FLAG;

	D(fprintf(logfile, "rfe: erp=%x pid=%x ccs=%x btarget=%x\n", 

		 env->pregs[PR_ERP], env->pregs[PR_PID],

		 env->pregs[PR_CCS],

		 env->btarget));

	cris_ccs_rshift(env);

	/* RFE sets the P_FLAG only if the R_FLAG is not set.  */

	if (!rflag)

		env->pregs[PR_CCS] |= P_FLAG;

}

void helper_rfn(void)

{

	int rflag = env->pregs[PR_CCS] & R_FLAG;

	D(fprintf(logfile, "rfn: erp=%x pid=%x ccs=%x btarget=%x\n", 

		 env->pregs[PR_ERP], env->pregs[PR_PID],

		 env->pregs[PR_CCS],

		 env->btarget));

	cris_ccs_rshift(env);

	/* Set the P_FLAG only if the R_FLAG is not set.  */

	if (!rflag)

		env->pregs[PR_CCS] |= P_FLAG;

    /* Always set the M flag.  */

    env->pregs[PR_CCS] |= M_FLAG;

}

void do_unassigned_access(target_phys_addr_t addr, int is_write, int is_exec,

                          int is_asi, int size)

{

	D(printf("%s addr=%x w=%d ex=%d asi=%d, size=%d\n",

		__func__, addr, is_write, is_exec, is_asi, size));

}

static void evaluate_flags_writeback(uint32_t flags)

{

	int x;

	/* Extended arithmetics, leave the z flag alone.  */

	x = env->cc_x;

	if ((x || env->cc_op == CC_OP_ADDC)

	    && flags & Z_FLAG)

		env->cc_mask &= ~Z_FLAG;

	/* all insn clear the x-flag except setf or clrf.  */

	env->pregs[PR_CCS] &= ~(env->cc_mask | X_FLAG);

	flags &= env->cc_mask;

	env->pregs[PR_CCS] |= flags;

}

void helper_evaluate_flags_muls(void)

{

	uint32_t src;

	uint32_t dst;

	uint32_t res;

	uint32_t flags = 0;

	int64_t tmp;

	int32_t mof;

	int dneg;

	src = env->cc_src;

	dst = env->cc_dest;

	res = env->cc_result;

	dneg = ((int32_t)res) < 0;

	mof = env->pregs[PR_MOF];

	tmp = mof;

	tmp <<= 32;

	tmp |= res;

	if (tmp == 0)

		flags |= Z_FLAG;

	else if (tmp < 0)

		flags |= N_FLAG;

	if ((dneg && mof != -1)

	    || (!dneg && mof != 0))

		flags |= V_FLAG;

	evaluate_flags_writeback(flags);

}

void  helper_evaluate_flags_mulu(void)

{

	uint32_t src;

	uint32_t dst;

	uint32_t res;

	uint32_t flags = 0;

	uint64_t tmp;

	uint32_t mof;

	src = env->cc_src;

	dst = env->cc_dest;

	res = env->cc_result;

	mof = env->pregs[PR_MOF];

	tmp = mof;

	tmp <<= 32;

	tmp |= res;

	if (tmp == 0)

		flags |= Z_FLAG;

	else if (tmp >> 63)

		flags |= N_FLAG;

	if (mof)

		flags |= V_FLAG;

	evaluate_flags_writeback(flags);

}

void  helper_evaluate_flags_mcp(void)

{

	uint32_t src;

	uint32_t dst;

	uint32_t res;

	uint32_t flags = 0;

	src = env->cc_src;

	dst = env->cc_dest;

	res = env->cc_result;

	if ((res & 0x80000000L) != 0L)

	{

		flags |= N_FLAG;

		if (((src & 0x80000000L) == 0L)

		    && ((dst & 0x80000000L) == 0L))

		{

			flags |= V_FLAG;

		}

		else if (((src & 0x80000000L) != 0L) &&

			 ((dst & 0x80000000L) != 0L))

		{

			flags |= R_FLAG;

		}

	}

	else

	{

		if (res == 0L)

			flags |= Z_FLAG;

		if (((src & 0x80000000L) != 0L)

		    && ((dst & 0x80000000L) != 0L))

			flags |= V_FLAG;

		if ((dst & 0x80000000L) != 0L

		    || (src & 0x80000000L) != 0L)

			flags |= R_FLAG;

	}

	evaluate_flags_writeback(flags);

}

void  helper_evaluate_flags_alu_4(void)

{

	uint32_t src;

	uint32_t dst;

	uint32_t res;

	uint32_t flags = 0;

	src = env->cc_src;

	dst = env->cc_dest;

	/* Reconstruct the result.  */

	switch (env->cc_op)

	{

		case CC_OP_SUB:

			res = dst - src;

			break;

		case CC_OP_ADD:

			res = dst + src;

			break;

		default:

			res = env->cc_result;

			break;

	}

	if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)

		src = ~src;

	if ((res & 0x80000000L) != 0L)

	{

		flags |= N_FLAG;

		if (((src & 0x80000000L) == 0L)

		    && ((dst & 0x80000000L) == 0L))

		{

			flags |= V_FLAG;

		}

		else if (((src & 0x80000000L) != 0L) &&

			 ((dst & 0x80000000L) != 0L))

		{

			flags |= C_FLAG;

		}

	}

	else

	{

		if (res == 0L)

			flags |= Z_FLAG;

		if (((src & 0x80000000L) != 0L)

		    && ((dst & 0x80000000L) != 0L))

			flags |= V_FLAG;

		if ((dst & 0x80000000L) != 0L

		    || (src & 0x80000000L) != 0L)

			flags |= C_FLAG;

	}

	if (env->cc_op == CC_OP_SUB

	    || env->cc_op == CC_OP_CMP) {

		flags ^= C_FLAG;

	}

	evaluate_flags_writeback(flags);

}

void  helper_evaluate_flags_move_4 (void)

{

	uint32_t res;

	uint32_t flags = 0;

	res = env->cc_result;

	if ((int32_t)res < 0)

		flags |= N_FLAG;

	else if (res == 0L)

		flags |= Z_FLAG;

	evaluate_flags_writeback(flags);

}

void  helper_evaluate_flags_move_2 (void)

{

	uint32_t src;

	uint32_t flags = 0;

	uint16_t res;

	src = env->cc_src;

	res = env->cc_result;

	if ((int16_t)res < 0L)

		flags |= N_FLAG;

	else if (res == 0)

		flags |= Z_FLAG;

	evaluate_flags_writeback(flags);

}

/* TODO: This is expensive. We could split things up and only evaluate part of

   CCR on a need to know basis. For now, we simply re-evaluate everything.  */

void helper_evaluate_flags (void)

{

	uint32_t src;

	uint32_t dst;

	uint32_t res;

	uint32_t flags = 0;

	src = env->cc_src;

	dst = env->cc_dest;

	res = env->cc_result;

	if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)

		src = ~src;

	/* Now, evaluate the flags. This stuff is based on

	   Per Zander's CRISv10 simulator.  */

	switch (env->cc_size)

	{

		case 1:

			if ((res & 0x80L) != 0L)

			{

				flags |= N_FLAG;

				if (((src & 0x80L) == 0L)

				    && ((dst & 0x80L) == 0L))

				{

					flags |= V_FLAG;

				}

				else if (((src & 0x80L) != 0L)

					 && ((dst & 0x80L) != 0L))

				{

					flags |= C_FLAG;

				}

			}

			else

			{

				if ((res & 0xFFL) == 0L)

				{

					flags |= Z_FLAG;

				}

				if (((src & 0x80L) != 0L)

				    && ((dst & 0x80L) != 0L))

				{

					flags |= V_FLAG;

				}

				if ((dst & 0x80L) != 0L

				    || (src & 0x80L) != 0L)

				{

					flags |= C_FLAG;

				}

			}

			break;

		case 2:

			if ((res & 0x8000L) != 0L)

			{

				flags |= N_FLAG;

				if (((src & 0x8000L) == 0L)

				    && ((dst & 0x8000L) == 0L))

				{

					flags |= V_FLAG;

				}

				else if (((src & 0x8000L) != 0L)

					 && ((dst & 0x8000L) != 0L))

				{

					flags |= C_FLAG;

				}

			}

			else

			{

				if ((res & 0xFFFFL) == 0L)

				{