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-rw-r--r--target-arm/translate.c246
1 files changed, 243 insertions, 3 deletions
diff --git a/target-arm/translate.c b/target-arm/translate.c
index 025c7a53eb..5a818afc02 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -4160,6 +4160,195 @@ static int gen_set_psr_im(DisasContext *s, uint32_t mask, int spsr, uint32_t val
return gen_set_psr(s, mask, spsr, tmp);
}
+static bool msr_banked_access_decode(DisasContext *s, int r, int sysm, int rn,
+ int *tgtmode, int *regno)
+{
+ /* Decode the r and sysm fields of MSR/MRS banked accesses into
+ * the target mode and register number, and identify the various
+ * unpredictable cases.
+ * MSR (banked) and MRS (banked) are CONSTRAINED UNPREDICTABLE if:
+ * + executed in user mode
+ * + using R15 as the src/dest register
+ * + accessing an unimplemented register
+ * + accessing a register that's inaccessible at current PL/security state*
+ * + accessing a register that you could access with a different insn
+ * We choose to UNDEF in all these cases.
+ * Since we don't know which of the various AArch32 modes we are in
+ * we have to defer some checks to runtime.
+ * Accesses to Monitor mode registers from Secure EL1 (which implies
+ * that EL3 is AArch64) must trap to EL3.
+ *
+ * If the access checks fail this function will emit code to take
+ * an exception and return false. Otherwise it will return true,
+ * and set *tgtmode and *regno appropriately.
+ */
+ int exc_target = default_exception_el(s);
+
+ /* These instructions are present only in ARMv8, or in ARMv7 with the
+ * Virtualization Extensions.
+ */
+ if (!arm_dc_feature(s, ARM_FEATURE_V8) &&
+ !arm_dc_feature(s, ARM_FEATURE_EL2)) {
+ goto undef;
+ }
+
+ if (IS_USER(s) || rn == 15) {
+ goto undef;
+ }
+
+ /* The table in the v8 ARM ARM section F5.2.3 describes the encoding
+ * of registers into (r, sysm).
+ */
+ if (r) {
+ /* SPSRs for other modes */
+ switch (sysm) {
+ case 0xe: /* SPSR_fiq */
+ *tgtmode = ARM_CPU_MODE_FIQ;
+ break;
+ case 0x10: /* SPSR_irq */
+ *tgtmode = ARM_CPU_MODE_IRQ;
+ break;
+ case 0x12: /* SPSR_svc */
+ *tgtmode = ARM_CPU_MODE_SVC;
+ break;
+ case 0x14: /* SPSR_abt */
+ *tgtmode = ARM_CPU_MODE_ABT;
+ break;
+ case 0x16: /* SPSR_und */
+ *tgtmode = ARM_CPU_MODE_UND;
+ break;
+ case 0x1c: /* SPSR_mon */
+ *tgtmode = ARM_CPU_MODE_MON;
+ break;
+ case 0x1e: /* SPSR_hyp */
+ *tgtmode = ARM_CPU_MODE_HYP;
+ break;
+ default: /* unallocated */
+ goto undef;
+ }
+ /* We arbitrarily assign SPSR a register number of 16. */
+ *regno = 16;
+ } else {
+ /* general purpose registers for other modes */
+ switch (sysm) {
+ case 0x0 ... 0x6: /* 0b00xxx : r8_usr ... r14_usr */
+ *tgtmode = ARM_CPU_MODE_USR;
+ *regno = sysm + 8;
+ break;
+ case 0x8 ... 0xe: /* 0b01xxx : r8_fiq ... r14_fiq */
+ *tgtmode = ARM_CPU_MODE_FIQ;
+ *regno = sysm;
+ break;
+ case 0x10 ... 0x11: /* 0b1000x : r14_irq, r13_irq */
+ *tgtmode = ARM_CPU_MODE_IRQ;
+ *regno = sysm & 1 ? 13 : 14;
+ break;
+ case 0x12 ... 0x13: /* 0b1001x : r14_svc, r13_svc */
+ *tgtmode = ARM_CPU_MODE_SVC;
+ *regno = sysm & 1 ? 13 : 14;
+ break;
+ case 0x14 ... 0x15: /* 0b1010x : r14_abt, r13_abt */
+ *tgtmode = ARM_CPU_MODE_ABT;
+ *regno = sysm & 1 ? 13 : 14;
+ break;
+ case 0x16 ... 0x17: /* 0b1011x : r14_und, r13_und */
+ *tgtmode = ARM_CPU_MODE_UND;
+ *regno = sysm & 1 ? 13 : 14;
+ break;
+ case 0x1c ... 0x1d: /* 0b1110x : r14_mon, r13_mon */
+ *tgtmode = ARM_CPU_MODE_MON;
+ *regno = sysm & 1 ? 13 : 14;
+ break;
+ case 0x1e ... 0x1f: /* 0b1111x : elr_hyp, r13_hyp */
+ *tgtmode = ARM_CPU_MODE_HYP;
+ /* Arbitrarily pick 17 for ELR_Hyp (which is not a banked LR!) */
+ *regno = sysm & 1 ? 13 : 17;
+ break;
+ default: /* unallocated */
+ goto undef;
+ }
+ }
+
+ /* Catch the 'accessing inaccessible register' cases we can detect
+ * at translate time.
+ */
+ switch (*tgtmode) {
+ case ARM_CPU_MODE_MON:
+ if (!arm_dc_feature(s, ARM_FEATURE_EL3) || s->ns) {
+ goto undef;
+ }
+ if (s->current_el == 1) {
+ /* If we're in Secure EL1 (which implies that EL3 is AArch64)
+ * then accesses to Mon registers trap to EL3
+ */
+ exc_target = 3;
+ goto undef;
+ }
+ break;
+ case ARM_CPU_MODE_HYP:
+ /* Note that we can forbid accesses from EL2 here because they
+ * must be from Hyp mode itself
+ */
+ if (!arm_dc_feature(s, ARM_FEATURE_EL2) || s->current_el < 3) {
+ goto undef;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return true;
+
+undef:
+ /* If we get here then some access check did not pass */
+ gen_exception_insn(s, 4, EXCP_UDEF, syn_uncategorized(), exc_target);
+ return false;
+}
+
+static void gen_msr_banked(DisasContext *s, int r, int sysm, int rn)
+{
+ TCGv_i32 tcg_reg, tcg_tgtmode, tcg_regno;
+ int tgtmode = 0, regno = 0;
+
+ if (!msr_banked_access_decode(s, r, sysm, rn, &tgtmode, &regno)) {
+ return;
+ }
+
+ /* Sync state because msr_banked() can raise exceptions */
+ gen_set_condexec(s);
+ gen_set_pc_im(s, s->pc - 4);
+ tcg_reg = load_reg(s, rn);
+ tcg_tgtmode = tcg_const_i32(tgtmode);
+ tcg_regno = tcg_const_i32(regno);
+ gen_helper_msr_banked(cpu_env, tcg_reg, tcg_tgtmode, tcg_regno);
+ tcg_temp_free_i32(tcg_tgtmode);
+ tcg_temp_free_i32(tcg_regno);
+ tcg_temp_free_i32(tcg_reg);
+ s->is_jmp = DISAS_UPDATE;
+}
+
+static void gen_mrs_banked(DisasContext *s, int r, int sysm, int rn)
+{
+ TCGv_i32 tcg_reg, tcg_tgtmode, tcg_regno;
+ int tgtmode = 0, regno = 0;
+
+ if (!msr_banked_access_decode(s, r, sysm, rn, &tgtmode, &regno)) {
+ return;
+ }
+
+ /* Sync state because mrs_banked() can raise exceptions */
+ gen_set_condexec(s);
+ gen_set_pc_im(s, s->pc - 4);
+ tcg_reg = tcg_temp_new_i32();
+ tcg_tgtmode = tcg_const_i32(tgtmode);
+ tcg_regno = tcg_const_i32(regno);
+ gen_helper_mrs_banked(tcg_reg, cpu_env, tcg_tgtmode, tcg_regno);
+ tcg_temp_free_i32(tcg_tgtmode);
+ tcg_temp_free_i32(tcg_regno);
+ store_reg(s, rn, tcg_reg);
+ s->is_jmp = DISAS_UPDATE;
+}
+
/* Generate an old-style exception return. Marks pc as dead. */
static void gen_exception_return(DisasContext *s, TCGv_i32 pc)
{
@@ -8022,7 +8211,26 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
sh = (insn >> 4) & 0xf;
rm = insn & 0xf;
switch (sh) {
- case 0x0: /* move program status register */
+ case 0x0: /* MSR, MRS */
+ if (insn & (1 << 9)) {
+ /* MSR (banked) and MRS (banked) */
+ int sysm = extract32(insn, 16, 4) |
+ (extract32(insn, 8, 1) << 4);
+ int r = extract32(insn, 22, 1);
+
+ if (op1 & 1) {
+ /* MSR (banked) */
+ gen_msr_banked(s, r, sysm, rm);
+ } else {
+ /* MRS (banked) */
+ int rd = extract32(insn, 12, 4);
+
+ gen_mrs_banked(s, r, sysm, rd);
+ }
+ break;
+ }
+
+ /* MSR, MRS (for PSRs) */
if (op1 & 1) {
/* PSR = reg */
tmp = load_reg(s, rm);
@@ -10133,6 +10341,18 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
if (arm_dc_feature(s, ARM_FEATURE_M)) {
goto illegal_op;
}
+
+ if (extract32(insn, 5, 1)) {
+ /* MSR (banked) */
+ int sysm = extract32(insn, 8, 4) |
+ (extract32(insn, 4, 1) << 4);
+ int r = op & 1;
+
+ gen_msr_banked(s, r, sysm, rm);
+ break;
+ }
+
+ /* MSR (for PSRs) */
tmp = load_reg(s, rn);
if (gen_set_psr(s,
msr_mask(s, (insn >> 8) & 0xf, op == 1),
@@ -10205,7 +10425,17 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
tcg_gen_subi_i32(tmp, tmp, insn & 0xff);
gen_exception_return(s, tmp);
break;
- case 6: /* mrs cpsr. */
+ case 6: /* MRS */
+ if (extract32(insn, 5, 1)) {
+ /* MRS (banked) */
+ int sysm = extract32(insn, 16, 4) |
+ (extract32(insn, 4, 1) << 4);
+
+ gen_mrs_banked(s, 0, sysm, rd);
+ break;
+ }
+
+ /* mrs cpsr */
tmp = tcg_temp_new_i32();
if (arm_dc_feature(s, ARM_FEATURE_M)) {
addr = tcg_const_i32(insn & 0xff);
@@ -10216,7 +10446,17 @@ static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
}
store_reg(s, rd, tmp);
break;
- case 7: /* mrs spsr. */
+ case 7: /* MRS */
+ if (extract32(insn, 5, 1)) {
+ /* MRS (banked) */
+ int sysm = extract32(insn, 16, 4) |
+ (extract32(insn, 4, 1) << 4);
+
+ gen_mrs_banked(s, 1, sysm, rd);
+ break;
+ }
+
+ /* mrs spsr. */
/* Not accessible in user mode. */
if (IS_USER(s) || arm_dc_feature(s, ARM_FEATURE_M)) {
goto illegal_op;
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-05 03:18:04 +0000