qemu/target-microblaze/op_helper.c
Edgar E. Iglesias e1aa325409 microblaze: Dont segfault when singlestepping first insn.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@petalogix.com>
2010-02-20 14:03:14 +01:00

285 lines
7.4 KiB
C

/*
* Microblaze helper routines.
*
* Copyright (c) 2009 Edgar E. Iglesias <edgar.iglesias@gmail.com>.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include "exec.h"
#include "helper.h"
#include "host-utils.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;
ret = cpu_mb_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);
}
}
cpu_loop_exit();
}
env = saved_env;
}
#endif
void helper_raise_exception(uint32_t index)
{
env->exception_index = index;
cpu_loop_exit();
}
void helper_debug(void)
{
int i;
qemu_log("PC=%8.8x\n", env->sregs[SR_PC]);
qemu_log("rmsr=%x resr=%x rear=%x debug[%x] imm=%x iflags=%x\n",
env->sregs[SR_MSR], env->sregs[SR_ESR], env->sregs[SR_EAR],
env->debug, env->imm, env->iflags);
qemu_log("btaken=%d btarget=%x mode=%s(saved=%s) eip=%d ie=%d\n",
env->btaken, env->btarget,
(env->sregs[SR_MSR] & MSR_UM) ? "user" : "kernel",
(env->sregs[SR_MSR] & MSR_UMS) ? "user" : "kernel",
(env->sregs[SR_MSR] & MSR_EIP),
(env->sregs[SR_MSR] & MSR_IE));
for (i = 0; i < 32; i++) {
qemu_log("r%2.2d=%8.8x ", i, env->regs[i]);
if ((i + 1) % 4 == 0)
qemu_log("\n");
}
qemu_log("\n\n");
}
static inline uint32_t compute_carry(uint32_t a, uint32_t b, uint32_t cin)
{
uint32_t cout = 0;
if ((b == ~0) && cin)
cout = 1;
else if ((~0 - a) < (b + cin))
cout = 1;
return cout;
}
uint32_t helper_cmp(uint32_t a, uint32_t b)
{
uint32_t t;
t = b + ~a + 1;
if ((b & 0x80000000) ^ (a & 0x80000000))
t = (t & 0x7fffffff) | (b & 0x80000000);
return t;
}
uint32_t helper_cmpu(uint32_t a, uint32_t b)
{
uint32_t t;
t = b + ~a + 1;
if ((b & 0x80000000) ^ (a & 0x80000000))
t = (t & 0x7fffffff) | (a & 0x80000000);
return t;
}
uint32_t helper_addkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
{
uint32_t d, cf = 0, ncf;
if (c)
cf = env->sregs[SR_MSR] >> 31;
assert(cf == 0 || cf == 1);
d = a + b + cf;
if (!k) {
ncf = compute_carry(a, b, cf);
assert(ncf == 0 || ncf == 1);
if (ncf)
env->sregs[SR_MSR] |= MSR_C | MSR_CC;
else
env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
}
D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
d, a, b, cf, ncf, k, c));
return d;
}
uint32_t helper_subkc(uint32_t a, uint32_t b, uint32_t k, uint32_t c)
{
uint32_t d, cf = 1, ncf;
if (c)
cf = env->sregs[SR_MSR] >> 31;
assert(cf == 0 || cf == 1);
d = b + ~a + cf;
if (!k) {
ncf = compute_carry(b, ~a, cf);
assert(ncf == 0 || ncf == 1);
if (ncf)
env->sregs[SR_MSR] |= MSR_C | MSR_CC;
else
env->sregs[SR_MSR] &= ~(MSR_C | MSR_CC);
}
D(qemu_log("%x = %x + %x cf=%d ncf=%d k=%d c=%d\n",
d, a, b, cf, ncf, k, c));
return d;
}
static inline int div_prepare(uint32_t a, uint32_t b)
{
if (b == 0) {
env->sregs[SR_MSR] |= MSR_DZ;
if ((env->sregs[SR_MSR] & MSR_EE)
&& !(env->pvr.regs[2] & PVR2_DIV_ZERO_EXC_MASK)) {
env->sregs[SR_ESR] = ESR_EC_DIVZERO;
helper_raise_exception(EXCP_HW_EXCP);
}
return 0;
}
env->sregs[SR_MSR] &= ~MSR_DZ;
return 1;
}
uint32_t helper_divs(uint32_t a, uint32_t b)
{
if (!div_prepare(a, b))
return 0;
return (int32_t)a / (int32_t)b;
}
uint32_t helper_divu(uint32_t a, uint32_t b)
{
if (!div_prepare(a, b))
return 0;
return a / b;
}
uint32_t helper_pcmpbf(uint32_t a, uint32_t b)
{
unsigned int i;
uint32_t mask = 0xff000000;
for (i = 0; i < 4; i++) {
if ((a & mask) == (b & mask))
return i + 1;
mask >>= 8;
}
return 0;
}
void helper_memalign(uint32_t addr, uint32_t dr, uint32_t wr, uint32_t mask)
{
if (addr & mask) {
qemu_log_mask(CPU_LOG_INT,
"unaligned access addr=%x mask=%x, wr=%d dr=r%d\n",
addr, mask, wr, dr);
env->sregs[SR_EAR] = addr;
env->sregs[SR_ESR] = ESR_EC_UNALIGNED_DATA | (wr << 10) \
| (dr & 31) << 5;
if (mask == 3) {
env->sregs[SR_ESR] |= 1 << 11;
}
if (!(env->sregs[SR_MSR] & MSR_EE)) {
return;
}
helper_raise_exception(EXCP_HW_EXCP);
}
}
#if !defined(CONFIG_USER_ONLY)
/* Writes/reads to the MMU's special regs end up here. */
uint32_t helper_mmu_read(uint32_t rn)
{
return mmu_read(env, rn);
}
void helper_mmu_write(uint32_t rn, uint32_t v)
{
mmu_write(env, rn, v);
}
#endif
void do_unassigned_access(target_phys_addr_t addr, int is_write, int is_exec,
int is_asi, int size)
{
CPUState *saved_env;
if (!cpu_single_env) {
/* XXX: ??? */
return;
}
/* XXX: hack to restore env in all cases, even if not called from
generated code */
saved_env = env;
env = cpu_single_env;
qemu_log_mask(CPU_LOG_INT, "Unassigned " TARGET_FMT_plx " wr=%d exe=%d\n",
addr, is_write, is_exec);
if (!(env->sregs[SR_MSR] & MSR_EE)) {
env = saved_env;
return;
}
env->sregs[SR_EAR] = addr;
if (is_exec) {
if ((env->pvr.regs[2] & PVR2_IOPB_BUS_EXC_MASK)) {
env->sregs[SR_ESR] = ESR_EC_INSN_BUS;
helper_raise_exception(EXCP_HW_EXCP);
}
} else {
if ((env->pvr.regs[2] & PVR2_DOPB_BUS_EXC_MASK)) {
env->sregs[SR_ESR] = ESR_EC_DATA_BUS;
helper_raise_exception(EXCP_HW_EXCP);
}
}
env = saved_env;
}