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* Copyright (c) 2007 CodeSourcery
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, see <http://www.gnu.org/licenses/>.
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#include "qemu/osdep.h"
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#include "exec/helper-proto.h"
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#include "exec/exec-all.h"
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#include "exec/cpu_ldst.h"
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#include "exec/semihost.h"
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#if defined(CONFIG_USER_ONLY)
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void m68k_cpu_do_interrupt(CPUState *cs)
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cs->exception_index = -1;
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static inline void do_interrupt_m68k_hardirq(CPUM68KState *env)
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/* Try to fill the TLB and return an exception if error. If retaddr is
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NULL, it means that the function was called in C code (i.e. not
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from generated code or from helper.c) */
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void tlb_fill(CPUState *cs, target_ulong addr, MMUAccessType access_type,
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int mmu_idx, uintptr_t retaddr)
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ret = m68k_cpu_handle_mmu_fault(cs, addr, access_type, mmu_idx);
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/* now we have a real cpu fault */
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cpu_restore_state(cs, retaddr);
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static void do_rte(CPUM68KState *env)
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fmt = cpu_ldl_kernel(env, sp);
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env->pc = cpu_ldl_kernel(env, sp + 4);
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sp |= (fmt >> 28) & 3;
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env->aregs[7] = sp + 8;
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helper_set_sr(env, fmt);
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static void do_interrupt_all(CPUM68KState *env, int is_hw)
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CPUState *cs = CPU(m68k_env_get_cpu(env));
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switch (cs->exception_index) {
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/* Return from an exception. */
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if (semihosting_enabled()
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&& (env->sr & SR_S) != 0
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&& cpu_lduw_code(env, env->pc - 4) == 0x4e71
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&& cpu_ldl_code(env, env->pc) == 0x4e7bf000) {
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do_m68k_semihosting(env, env->dregs[0]);
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cs->exception_index = EXCP_HLT;
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if (cs->exception_index >= EXCP_TRAP0
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&& cs->exception_index <= EXCP_TRAP15) {
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/* Move the PC after the trap instruction. */
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vector = cs->exception_index << 2;
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fmt |= cpu_m68k_get_ccr(env);
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env->sr = (env->sr & ~SR_I) | (env->pending_level << SR_I_SHIFT);
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fmt |= (sp & 3) << 28;
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/* ??? This could cause MMU faults. */
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cpu_stl_kernel(env, sp, retaddr);
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cpu_stl_kernel(env, sp, fmt);
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/* Jump to vector. */
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env->pc = cpu_ldl_kernel(env, env->vbr + vector);
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void m68k_cpu_do_interrupt(CPUState *cs)
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M68kCPU *cpu = M68K_CPU(cs);
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CPUM68KState *env = &cpu->env;
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do_interrupt_all(env, 0);
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static inline void do_interrupt_m68k_hardirq(CPUM68KState *env)
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do_interrupt_all(env, 1);
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bool m68k_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
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M68kCPU *cpu = M68K_CPU(cs);
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CPUM68KState *env = &cpu->env;
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if (interrupt_request & CPU_INTERRUPT_HARD
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&& ((env->sr & SR_I) >> SR_I_SHIFT) < env->pending_level) {
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/* Real hardware gets the interrupt vector via an IACK cycle
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at this point. Current emulated hardware doesn't rely on
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this, so we provide/save the vector when the interrupt is
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cs->exception_index = env->pending_vector;
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do_interrupt_m68k_hardirq(env);
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static void raise_exception(CPUM68KState *env, int tt)
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CPUState *cs = CPU(m68k_env_get_cpu(env));
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cs->exception_index = tt;
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void HELPER(raise_exception)(CPUM68KState *env, uint32_t tt)
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raise_exception(env, tt);
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void HELPER(divu)(CPUM68KState *env, uint32_t word)
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/* ??? This needs to make sure the throwing location is accurate. */
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raise_exception(env, EXCP_DIV0);
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env->cc_v = (word && quot > 0xffff ? -1 : 0);
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void HELPER(divs)(CPUM68KState *env, uint32_t word)
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raise_exception(env, EXCP_DIV0);
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env->cc_v = (word && quot != (int16_t)quot ? -1 : 0);