This patch adds the Cortex-M4 CPU. The M4 is basically the same as the M3,
the main differences being the DSP instructions and an optional FPU.
The DSP instructions are already implemented in Qemu, as the A and R profiles
use them.
I created an ARM_FEATURE_THUMB_DSP to be added to any non-M thumb2-compatible
CPU that uses DSP instructions, and I manually added it to the M4 in its initfn.
The optional FPU in the M4 could be added in the future as a "Cortex-M4F" CPU.
All we'd have to do is add the ARM_FEATURE_VFP4 to the initfn.
There are 85 DSP instructions (all of them thumb2). On disas_thumb2_insn
the DSP feature is tested before the instruction is generated; if it's not
enabled then its an illegal op.
Signed-off-by: Aurelio C. Remonda <aurelioremo...@gmail.com>
---
target-arm/cpu.c | 22 +++++++++
target-arm/cpu.h | 1 +
target-arm/translate.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++--
3 files changed, 149 insertions(+), 4 deletions(-)
diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index 3ca3fa8..9be4a06 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -512,6 +512,10 @@ static void arm_cpu_realizefn(DeviceState *dev, Error
**errp)
if (arm_feature(env, ARM_FEATURE_CBAR_RO)) {
set_feature(env, ARM_FEATURE_CBAR);
}
+ if (arm_feature(env,ARM_FEATURE_THUMB2) &&
+ !arm_feature(env,ARM_FEATURE_M)) {
+ set_feature(env, ARM_FEATURE_THUMB_DSP);
+ }
if (cpu->reset_hivecs) {
cpu->reset_sctlr |= (1 << 13);
@@ -761,6 +765,22 @@ static void cortex_m3_initfn(Object *obj)
set_feature(&cpu->env, ARM_FEATURE_M);
cpu->midr = 0x410fc231;
}
+static void cortex_m4_initfn(Object *obj)
+{
+ ARMCPU *cpu = ARM_CPU(obj);
+ set_feature(&cpu->env, ARM_FEATURE_V7);
+ set_feature(&cpu->env, ARM_FEATURE_M);
+ set_feature(&cpu->env, ARM_FEATURE_THUMB_DSP);
+ cpu->midr = 0x410fc240;
+ /* Main id register CPUID bit assignments
+ * Bits NAME Function
+ * [31:24] IMPLEMENTER Indicates implementor: 0x41 = ARM
+ * [23:20] VARIANT Indicates processor revision: 0x0 = Revision 0
+ * [19:16] (Constant) Reads as 0xF
+ * [15:4] PARTNO Indicates part number: 0xC24 = Cortex-M4
+ * [3:0] REVISION Indicates patch release: 0x0 = Patch 0.
+ */
+}
static void arm_v7m_class_init(ObjectClass *oc, void *data)
{
@@ -1164,6 +1184,8 @@ static const ARMCPUInfo arm_cpus[] = {
{ .name = "arm11mpcore", .initfn = arm11mpcore_initfn },
{ .name = "cortex-m3", .initfn = cortex_m3_initfn,
.class_init = arm_v7m_class_init },
+ { .name = "cortex-m4", .initfn = cortex_m4_initfn,
+ .class_init = arm_v7m_class_init },
{ .name = "cortex-a8", .initfn = cortex_a8_initfn },
{ .name = "cortex-a9", .initfn = cortex_a9_initfn },
{ .name = "cortex-a15", .initfn = cortex_a15_initfn },
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index d4a5899..fa5c3bc 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -886,6 +886,7 @@ enum arm_features {
ARM_FEATURE_V8_SHA1, /* implements SHA1 part of v8 Crypto Extensions */
ARM_FEATURE_V8_SHA256, /* implements SHA256 part of v8 Crypto Extensions */
ARM_FEATURE_V8_PMULL, /* implements PMULL part of v8 Crypto Extensions */
+ ARM_FEATURE_THUMB_DSP,/* DSP insns supported in the Thumb encodings */
};
static inline int arm_feature(CPUARMState *env, int feature)
diff --git a/target-arm/translate.c b/target-arm/translate.c
index 9116529..c9d2e4f 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -9428,6 +9428,10 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
op = (insn >> 21) & 0xf;
if (op == 6) {
+ if (!arm_dc_feature(s, ARM_FEATURE_THUMB_DSP)) {
+ /* pkhtb, pkfbt are DSP instructions */
+ goto illegal_op;
+ }
/* Halfword pack. */
tmp = load_reg(s, rn);
tmp2 = load_reg(s, rm);
@@ -9502,13 +9506,37 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
switch (op) {
case 0: gen_sxth(tmp); break;
case 1: gen_uxth(tmp); break;
- case 2: gen_sxtb16(tmp); break;
- case 3: gen_uxtb16(tmp); break;
+ case 2:
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* sxtab16, sxtb16 are DSP instructions */
+ tcg_temp_free_i32(tmp);
+ goto illegal_op;
+ }
+ gen_sxtb16(tmp);
+ break;
+ case 3:
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* uxtb16, uxtab16 are DSP instructions */
+ tcg_temp_free_i32(tmp);
+ goto illegal_op;
+ }
+ gen_uxtb16(tmp);
+ break;
case 4: gen_sxtb(tmp); break;
case 5: gen_uxtb(tmp); break;
default: goto illegal_op;
}
+ /*-sxtab->-sxtab16->*/
if (rn != 15) {
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* sxtab, sxtah, uxtab, uxtah are DSP instructions.
+ * sxtb, sxth, uxtb, uxth are not DSP according to
+ * ARMv7-M Architecture Reference Manual
+ */
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ goto illegal_op;
+ }
tmp2 = load_reg(s, rn);
if ((op >> 1) == 1) {
gen_add16(tmp, tmp2);
@@ -9521,6 +9549,12 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
break;
case 2: /* SIMD add/subtract. */
op = (insn >> 20) & 7;
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP)) ){
+ /* add16, sub16, asx, sax, add8, sub8 (with q, s, sh, u, uh,
+ * and uq variants) and usad8, usada8
+ */
+ goto illegal_op;
+ }
shift = (insn >> 4) & 7;
if ((op & 3) == 3 || (shift & 3) == 3)
goto illegal_op;
@@ -9532,8 +9566,13 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
break;
case 3: /* Other data processing. */
op = ((insn >> 17) & 0x38) | ((insn >> 4) & 7);
+
if (op < 4) {
/* Saturating add/subtract. */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* qsub, qadd, qdadd, qdsub are DSP instructions. */
+ goto illegal_op;
+ }
tmp = load_reg(s, rn);
tmp2 = load_reg(s, rm);
if (op & 1)
@@ -9559,6 +9598,12 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
gen_revsh(tmp);
break;
case 0x10: /* sel */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* sel is a DSP instruction. */
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ goto illegal_op;
+ }
tmp2 = load_reg(s, rm);
tmp3 = tcg_temp_new_i32();
tcg_gen_ld_i32(tmp3, cpu_env, offsetof(CPUARMState, GE));
@@ -9624,6 +9669,15 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
}
break;
case 1: /* 16 x 16 -> 32 */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* smlabb, smlabt, smlatb, smlatt, smulbb, smulbt, smultt
+ * and smultb are DSP instructions
+ */
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
gen_mulxy(tmp, tmp2, op & 2, op & 1);
tcg_temp_free_i32(tmp2);
if (rs != 15) {
@@ -9634,6 +9688,14 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
break;
case 2: /* Dual multiply add. */
case 4: /* Dual multiply subtract. */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* smlad, smladx, smlsd, smusd are DSP instructions */
+
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
if (op)
gen_swap_half(tmp2);
gen_smul_dual(tmp, tmp2);
@@ -9656,6 +9718,13 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
}
break;
case 3: /* 32 * 16 -> 32msb */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* smlawb, smlawt, smulwt, smulwb are DSP instructions */
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
if (op)
tcg_gen_sari_i32(tmp2, tmp2, 16);
else
@@ -9673,6 +9742,15 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
}
break;
case 5: case 6: /* 32 * 32 -> 32msb (SMMUL, SMMLA, SMMLS) */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* smmla, smmls, smmul, smuad, smmlar,
+ * smmlsr, smmulr are DSP instructions
+ */
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
tmp64 = gen_muls_i64_i32(tmp, tmp2);
if (rs != 15) {
tmp = load_reg(s, rs);
@@ -9719,6 +9797,13 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
store_reg(s, rd, tmp);
} else if ((op & 0xe) == 0xc) {
/* Dual multiply accumulate long. */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* smlald, smlsld are DSP instructions */
+ /* need to free this so there's no TCG temporary leak */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
if (op & 1)
gen_swap_half(tmp2);
gen_smul_dual(tmp, tmp2);
@@ -9742,6 +9827,17 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
} else {
if (op & 8) {
/* smlalxy */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* smlalbb, smlalbt, smlaltb, smlaltt
+ * are DSP instructions
+ */
+ /* need to free this so there's no TCG
+ * temporary leak
+ */
+ tcg_temp_free_i32(tmp2);
+ tcg_temp_free_i32(tmp);
+ goto illegal_op;
+ }
gen_mulxy(tmp, tmp2, op & 2, op & 1);
tcg_temp_free_i32(tmp2);
tmp64 = tcg_temp_new_i64();
@@ -9754,6 +9850,12 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
}
if (op & 4) {
/* umaal */
+ if (!(arm_dc_feature(s, ARM_FEATURE_THUMB_DSP))){
+ /* ummal is a DSP instruction */
+ /* need to free this so there's no TCG temporary leak
*/
+ tcg_temp_free_i64(tmp64);
+ goto illegal_op;
+ }
gen_addq_lo(s, tmp64, rs);
gen_addq_lo(s, tmp64, rd);
} else if (op & 0x40) {
@@ -10018,14 +10120,34 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
tmp2 = tcg_const_i32(imm);
if (op & 4) {
/* Unsigned. */
- if ((op & 1) && shift == 0)
+ if ((op & 1) && shift == 0){
+ if (!(arm_dc_feature(s,
ARM_FEATURE_THUMB_DSP))){
+ /* usat16 is a DSP instruction */
+ /* need to free this so there's no TCG
+ * temporary leak
+ */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
gen_helper_usat16(tmp, cpu_env, tmp, tmp2);
+ }
else
gen_helper_usat(tmp, cpu_env, tmp, tmp2);
} else {
/* Signed. */
- if ((op & 1) && shift == 0)
+ if ((op & 1) && shift == 0){
+ if (!(arm_dc_feature(s,
ARM_FEATURE_THUMB_DSP))){
+ /* ssat16 is a DSP instruction */
+ /* need to free this so there's no TCG
+ * temporary leak
+ */
+ tcg_temp_free_i32(tmp);
+ tcg_temp_free_i32(tmp2);
+ goto illegal_op;
+ }
gen_helper_ssat16(tmp, cpu_env, tmp, tmp2);
+ }
else
gen_helper_ssat(tmp, cpu_env, tmp, tmp2);
}
--
1.9.1
