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target-mips: add restrictions for possible values in registers

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In Release 6 not all the values are allowed to be written to a register.
If the value is not valid or unsupported then it should stay unchanged.

For pre-R6 the existing behaviour has been changed only for CP0_Index register
as the current implementation does not seem to be correct - it looks like it
tries to limit the input value but the limit is higher than the actual
number of tlb entries.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
This commit is contained in:
Leon Alrae 2014-07-11 16:11:34 +01:00
parent a63eb0ce0f
commit ba801af429
1 changed files with 53 additions and 17 deletions
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70
target-mips/op_helper.c
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@ -959,14 +959,14 @@ target_ulong helper_dmfc0_watchlo(CPUMIPSState *env, uint32_t sel)
void helper_mtc0_index(CPUMIPSState *env, target_ulong arg1)
{
int num = 1;
unsigned int tmp = env->tlb->nb_tlb;
do {
tmp >>= 1;
num <<= 1;
} while (tmp);
env->CP0_Index = (env->CP0_Index & 0x80000000) | (arg1 & (num - 1));
uint32_t index_p = env->CP0_Index & 0x80000000;
uint32_t tlb_index = arg1 & 0x7fffffff;
if (tlb_index < env->tlb->nb_tlb) {
if (env->insn_flags & ISA_MIPS32R6) {
index_p |= arg1 & 0x80000000;
}
env->CP0_Index = index_p | tlb_index;
}
}
void helper_mtc0_mvpcontrol(CPUMIPSState *env, target_ulong arg1)
@ -1294,8 +1294,13 @@ void helper_mtc0_context(CPUMIPSState *env, target_ulong arg1)
void helper_mtc0_pagemask(CPUMIPSState *env, target_ulong arg1)
{
/* 1k pages not implemented */
env->CP0_PageMask = arg1 & (0x1FFFFFFF & (TARGET_PAGE_MASK << 1));
uint64_t mask = arg1 >> (TARGET_PAGE_BITS + 1);
if (!(env->insn_flags & ISA_MIPS32R6) || (arg1 == ~0) ||
(mask == 0x0000 || mask == 0x0003 || mask == 0x000F ||
mask == 0x003F || mask == 0x00FF || mask == 0x03FF ||
mask == 0x0FFF || mask == 0x3FFF || mask == 0xFFFF)) {
env->CP0_PageMask = arg1 & (0x1FFFFFFF & (TARGET_PAGE_MASK << 1));
}
}
void helper_mtc0_pagegrain(CPUMIPSState *env, target_ulong arg1)
@ -1309,7 +1314,13 @@ void helper_mtc0_pagegrain(CPUMIPSState *env, target_ulong arg1)
void helper_mtc0_wired(CPUMIPSState *env, target_ulong arg1)
{
env->CP0_Wired = arg1 % env->tlb->nb_tlb;
if (env->insn_flags & ISA_MIPS32R6) {
if (arg1 < env->tlb->nb_tlb) {
env->CP0_Wired = arg1;
}
} else {
env->CP0_Wired = arg1 % env->tlb->nb_tlb;
}
}
void helper_mtc0_srsconf0(CPUMIPSState *env, target_ulong arg1)
@ -1368,11 +1379,21 @@ void helper_mtc0_entryhi(CPUMIPSState *env, target_ulong arg1)
}
/* 1k pages not implemented */
val = arg1 & mask;
#if defined(TARGET_MIPS64)
val &= env->SEGMask;
if (env->insn_flags & ISA_MIPS32R6) {
int entryhi_r = extract64(arg1, 62, 2);
int config0_at = extract32(env->CP0_Config0, 13, 2);
bool no_supervisor = (env->CP0_Status_rw_bitmask & 0x8) == 0;
if ((entryhi_r == 2) ||
(entryhi_r == 1 && (no_supervisor || config0_at == 1))) {
/* skip EntryHi.R field if new value is reserved */
mask &= ~(0x3ull << 62);
}
}
mask &= env->SEGMask;
#endif
old = env->CP0_EntryHi;
val = (arg1 & mask) | (old & ~mask);
env->CP0_EntryHi = val;
if (env->CP0_Config3 & (1 << CP0C3_MT)) {
sync_c0_entryhi(env, env->current_tc);
@ -1402,6 +1423,13 @@ void helper_mtc0_status(CPUMIPSState *env, target_ulong arg1)
uint32_t val, old;
uint32_t mask = env->CP0_Status_rw_bitmask;
if (env->insn_flags & ISA_MIPS32R6) {
if (extract32(env->CP0_Status, CP0St_KSU, 2) == 0x3) {
mask &= ~(3 << CP0St_KSU);
}
mask &= ~(0x00180000 & arg1);
}
val = arg1 & mask;
old = env->CP0_Status;
env->CP0_Status = (env->CP0_Status & ~mask) | val;
@ -1457,6 +1485,9 @@ static void mtc0_cause(CPUMIPSState *cpu, target_ulong arg1)
if (cpu->insn_flags & ISA_MIPS32R2) {
mask |= 1 << CP0Ca_DC;
}
if (cpu->insn_flags & ISA_MIPS32R6) {
mask &= ~((1 << CP0Ca_WP) & arg1);
}
cpu->CP0_Cause = (cpu->CP0_Cause & ~mask) | (arg1 & mask);
@ -2391,8 +2422,9 @@ void helper_ctc1(CPUMIPSState *env, target_ulong arg1, uint32_t fs, uint32_t rt)
}
break;
case 25:
if (arg1 & 0xffffff00)
if ((env->insn_flags & ISA_MIPS32R6) || (arg1 & 0xffffff00)) {
return;
}
env->active_fpu.fcr31 = (env->active_fpu.fcr31 & 0x017fffff) | ((arg1 & 0xfe) << 24) |
((arg1 & 0x1) << 23);
break;
@ -2408,9 +2440,13 @@ void helper_ctc1(CPUMIPSState *env, target_ulong arg1, uint32_t fs, uint32_t rt)
((arg1 & 0x4) << 22);
break;
case 31:
if (arg1 & 0x007c0000)
return;
env->active_fpu.fcr31 = arg1;
if (env->insn_flags & ISA_MIPS32R6) {
uint32_t mask = 0xfefc0000;
env->active_fpu.fcr31 = (arg1 & ~mask) |
(env->active_fpu.fcr31 & mask);
} else if (!(arg1 & 0x007c0000)) {
env->active_fpu.fcr31 = arg1;
}
break;
default:
return;