qemu/linux-user/nios2/cpu_loop.c
Richard Henderson 17a406eec5 target/nios2: Split PC out of env->regs[]
It is cleaner to have a separate name for this variable.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220421151735.31996-17-richard.henderson@linaro.org>
2022-04-26 08:16:41 -07:00

161 lines
5.3 KiB
C

/*
* qemu user cpu loop
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu.h"
#include "user-internals.h"
#include "cpu_loop-common.h"
#include "signal-common.h"
void cpu_loop(CPUNios2State *env)
{
CPUState *cs = env_cpu(env);
int trapnr, ret;
for (;;) {
cpu_exec_start(cs);
trapnr = cpu_exec(cs);
cpu_exec_end(cs);
switch (trapnr) {
case EXCP_INTERRUPT:
/* just indicate that signals should be handled asap */
break;
case EXCP_TRAP:
/*
* TODO: This advance should be done in the translator, as
* hardware produces an advanced pc as part of all exceptions.
*/
env->pc += 4;
switch (env->error_code) {
case 0:
qemu_log_mask(CPU_LOG_INT, "\nSyscall\n");
ret = do_syscall(env, env->regs[2],
env->regs[4], env->regs[5], env->regs[6],
env->regs[7], env->regs[8], env->regs[9],
0, 0);
if (ret == -QEMU_ESIGRETURN) {
/* rt_sigreturn has set all state. */
break;
}
if (ret == -QEMU_ERESTARTSYS) {
env->pc -= 4;
break;
}
/*
* See the code after translate_rc_and_ret: all negative
* values are errors (aided by userspace restricted to 2G),
* errno is returned positive in r2, and error indication
* is a boolean in r7.
*/
env->regs[2] = abs(ret);
env->regs[7] = ret < 0;
break;
case 1:
qemu_log_mask(CPU_LOG_INT, "\nTrap 1\n");
force_sig_fault(TARGET_SIGUSR1, 0, env->pc);
break;
case 2:
qemu_log_mask(CPU_LOG_INT, "\nTrap 2\n");
force_sig_fault(TARGET_SIGUSR2, 0, env->pc);
break;
case 31:
qemu_log_mask(CPU_LOG_INT, "\nTrap 31\n");
/* Match kernel's breakpoint_c(). */
env->pc -= 4;
force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
break;
default:
qemu_log_mask(CPU_LOG_INT, "\nTrap %d\n", env->error_code);
force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLTRP, env->pc);
break;
case 16: /* QEMU specific, for __kuser_cmpxchg */
{
abi_ptr g = env->regs[4];
uint32_t *h, n, o;
if (g & 0x3) {
force_sig_fault(TARGET_SIGBUS, TARGET_BUS_ADRALN, g);
break;
}
ret = page_get_flags(g);
if (!(ret & PAGE_VALID)) {
force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR, g);
break;
}
if (!(ret & PAGE_READ) || !(ret & PAGE_WRITE)) {
force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_ACCERR, g);
break;
}
h = g2h(cs, g);
o = env->regs[5];
n = env->regs[6];
env->regs[2] = qatomic_cmpxchg(h, o, n) - o;
}
break;
}
break;
case EXCP_DEBUG:
force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
break;
default:
EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n",
trapnr);
abort();
}
process_pending_signals(env);
}
}
void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
{
env->regs[0] = 0;
env->regs[1] = regs->r1;
env->regs[2] = regs->r2;
env->regs[3] = regs->r3;
env->regs[4] = regs->r4;
env->regs[5] = regs->r5;
env->regs[6] = regs->r6;
env->regs[7] = regs->r7;
env->regs[8] = regs->r8;
env->regs[9] = regs->r9;
env->regs[10] = regs->r10;
env->regs[11] = regs->r11;
env->regs[12] = regs->r12;
env->regs[13] = regs->r13;
env->regs[14] = regs->r14;
env->regs[15] = regs->r15;
/* TODO: unsigned long orig_r2; */
env->regs[R_RA] = regs->ra;
env->regs[R_FP] = regs->fp;
env->regs[R_SP] = regs->sp;
env->regs[R_GP] = regs->gp;
env->regs[CR_ESTATUS] = regs->estatus;
env->pc = regs->ea;
/* TODO: unsigned long orig_r7; */
}