| /* |
| * ARM translation: M-profile NOCP special-case instructions |
| * |
| * Copyright (c) 2020 Linaro, Ltd. |
| * |
| * 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 2.1 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 "qemu/osdep.h" |
| #include "tcg/tcg-op.h" |
| #include "tcg/tcg-op-gvec.h" |
| #include "translate.h" |
| #include "translate-a32.h" |
| |
| #include "decode-m-nocp.c.inc" |
| |
| /* |
| * Decode VLLDM and VLSTM are nonstandard because: |
| * * if there is no FPU then these insns must NOP in |
| * Secure state and UNDEF in Nonsecure state |
| * * if there is an FPU then these insns do not have |
| * the usual behaviour that vfp_access_check() provides of |
| * being controlled by CPACR/NSACR enable bits or the |
| * lazy-stacking logic. |
| */ |
| static bool trans_VLLDM_VLSTM(DisasContext *s, arg_VLLDM_VLSTM *a) |
| { |
| TCGv_i32 fptr; |
| |
| if (!arm_dc_feature(s, ARM_FEATURE_M) || |
| !arm_dc_feature(s, ARM_FEATURE_V8)) { |
| return false; |
| } |
| |
| if (a->op) { |
| /* |
| * T2 encoding ({D0-D31} reglist): v8.1M and up. We choose not |
| * to take the IMPDEF option to make memory accesses to the stack |
| * slots that correspond to the D16-D31 registers (discarding |
| * read data and writing UNKNOWN values), so for us the T2 |
| * encoding behaves identically to the T1 encoding. |
| */ |
| if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { |
| return false; |
| } |
| } else { |
| /* |
| * T1 encoding ({D0-D15} reglist); undef if we have 32 Dregs. |
| * This is currently architecturally impossible, but we add the |
| * check to stay in line with the pseudocode. Note that we must |
| * emit code for the UNDEF so it takes precedence over the NOCP. |
| */ |
| if (dc_isar_feature(aa32_simd_r32, s)) { |
| unallocated_encoding(s); |
| return true; |
| } |
| } |
| |
| /* |
| * If not secure, UNDEF. We must emit code for this |
| * rather than returning false so that this takes |
| * precedence over the m-nocp.decode NOCP fallback. |
| */ |
| if (!s->v8m_secure) { |
| unallocated_encoding(s); |
| return true; |
| } |
| |
| s->eci_handled = true; |
| |
| /* If no fpu, NOP. */ |
| if (!dc_isar_feature(aa32_vfp, s)) { |
| clear_eci_state(s); |
| return true; |
| } |
| |
| fptr = load_reg(s, a->rn); |
| if (a->l) { |
| gen_helper_v7m_vlldm(cpu_env, fptr); |
| } else { |
| gen_helper_v7m_vlstm(cpu_env, fptr); |
| } |
| |
| clear_eci_state(s); |
| |
| /* |
| * End the TB, because we have updated FP control bits, |
| * and possibly VPR or LTPSIZE. |
| */ |
| s->base.is_jmp = DISAS_UPDATE_EXIT; |
| return true; |
| } |
| |
| static bool trans_VSCCLRM(DisasContext *s, arg_VSCCLRM *a) |
| { |
| int btmreg, topreg; |
| TCGv_i64 zero; |
| TCGv_i32 aspen, sfpa; |
| |
| if (!dc_isar_feature(aa32_m_sec_state, s)) { |
| /* Before v8.1M, fall through in decode to NOCP check */ |
| return false; |
| } |
| |
| /* Explicitly UNDEF because this takes precedence over NOCP */ |
| if (!arm_dc_feature(s, ARM_FEATURE_M_MAIN) || !s->v8m_secure) { |
| unallocated_encoding(s); |
| return true; |
| } |
| |
| s->eci_handled = true; |
| |
| if (!dc_isar_feature(aa32_vfp_simd, s)) { |
| /* NOP if we have neither FP nor MVE */ |
| clear_eci_state(s); |
| return true; |
| } |
| |
| /* |
| * If FPCCR.ASPEN != 0 && CONTROL_S.SFPA == 0 then there is no |
| * active floating point context so we must NOP (without doing |
| * any lazy state preservation or the NOCP check). |
| */ |
| aspen = load_cpu_field(v7m.fpccr[M_REG_S]); |
| sfpa = load_cpu_field(v7m.control[M_REG_S]); |
| tcg_gen_andi_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); |
| tcg_gen_xori_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); |
| tcg_gen_andi_i32(sfpa, sfpa, R_V7M_CONTROL_SFPA_MASK); |
| tcg_gen_or_i32(sfpa, sfpa, aspen); |
| arm_gen_condlabel(s); |
| tcg_gen_brcondi_i32(TCG_COND_EQ, sfpa, 0, s->condlabel.label); |
| |
| if (s->fp_excp_el != 0) { |
| gen_exception_insn_el(s, 0, EXCP_NOCP, |
| syn_uncategorized(), s->fp_excp_el); |
| return true; |
| } |
| |
| topreg = a->vd + a->imm - 1; |
| btmreg = a->vd; |
| |
| /* Convert to Sreg numbers if the insn specified in Dregs */ |
| if (a->size == 3) { |
| topreg = topreg * 2 + 1; |
| btmreg *= 2; |
| } |
| |
| if (topreg > 63 || (topreg > 31 && !(topreg & 1))) { |
| /* UNPREDICTABLE: we choose to undef */ |
| unallocated_encoding(s); |
| return true; |
| } |
| |
| /* Silently ignore requests to clear D16-D31 if they don't exist */ |
| if (topreg > 31 && !dc_isar_feature(aa32_simd_r32, s)) { |
| topreg = 31; |
| } |
| |
| if (!vfp_access_check(s)) { |
| return true; |
| } |
| |
| /* Zero the Sregs from btmreg to topreg inclusive. */ |
| zero = tcg_constant_i64(0); |
| if (btmreg & 1) { |
| write_neon_element64(zero, btmreg >> 1, 1, MO_32); |
| btmreg++; |
| } |
| for (; btmreg + 1 <= topreg; btmreg += 2) { |
| write_neon_element64(zero, btmreg >> 1, 0, MO_64); |
| } |
| if (btmreg == topreg) { |
| write_neon_element64(zero, btmreg >> 1, 0, MO_32); |
| btmreg++; |
| } |
| assert(btmreg == topreg + 1); |
| if (dc_isar_feature(aa32_mve, s)) { |
| store_cpu_field(tcg_constant_i32(0), v7m.vpr); |
| } |
| |
| clear_eci_state(s); |
| return true; |
| } |
| |
| /* |
| * M-profile provides two different sets of instructions that can |
| * access floating point system registers: VMSR/VMRS (which move |
| * to/from a general purpose register) and VLDR/VSTR sysreg (which |
| * move directly to/from memory). In some cases there are also side |
| * effects which must happen after any write to memory (which could |
| * cause an exception). So we implement the common logic for the |
| * sysreg access in gen_M_fp_sysreg_write() and gen_M_fp_sysreg_read(), |
| * which take pointers to callback functions which will perform the |
| * actual "read/write general purpose register" and "read/write |
| * memory" operations. |
| */ |
| |
| /* |
| * Emit code to store the sysreg to its final destination; frees the |
| * TCG temp 'value' it is passed. do_access is true to do the store, |
| * and false to skip it and only perform side-effects like base |
| * register writeback. |
| */ |
| typedef void fp_sysreg_storefn(DisasContext *s, void *opaque, TCGv_i32 value, |
| bool do_access); |
| /* |
| * Emit code to load the value to be copied to the sysreg; returns |
| * a new TCG temporary. do_access is true to do the store, |
| * and false to skip it and only perform side-effects like base |
| * register writeback. |
| */ |
| typedef TCGv_i32 fp_sysreg_loadfn(DisasContext *s, void *opaque, |
| bool do_access); |
| |
| /* Common decode/access checks for fp sysreg read/write */ |
| typedef enum FPSysRegCheckResult { |
| FPSysRegCheckFailed, /* caller should return false */ |
| FPSysRegCheckDone, /* caller should return true */ |
| FPSysRegCheckContinue, /* caller should continue generating code */ |
| } FPSysRegCheckResult; |
| |
| static FPSysRegCheckResult fp_sysreg_checks(DisasContext *s, int regno) |
| { |
| if (!dc_isar_feature(aa32_fpsp_v2, s) && !dc_isar_feature(aa32_mve, s)) { |
| return FPSysRegCheckFailed; |
| } |
| |
| switch (regno) { |
| case ARM_VFP_FPSCR: |
| case QEMU_VFP_FPSCR_NZCV: |
| break; |
| case ARM_VFP_FPSCR_NZCVQC: |
| if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { |
| return FPSysRegCheckFailed; |
| } |
| break; |
| case ARM_VFP_FPCXT_S: |
| case ARM_VFP_FPCXT_NS: |
| if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { |
| return FPSysRegCheckFailed; |
| } |
| if (!s->v8m_secure) { |
| return FPSysRegCheckFailed; |
| } |
| break; |
| case ARM_VFP_VPR: |
| case ARM_VFP_P0: |
| if (!dc_isar_feature(aa32_mve, s)) { |
| return FPSysRegCheckFailed; |
| } |
| break; |
| default: |
| return FPSysRegCheckFailed; |
| } |
| |
| /* |
| * FPCXT_NS is a special case: it has specific handling for |
| * "current FP state is inactive", and must do the PreserveFPState() |
| * but not the usual full set of actions done by ExecuteFPCheck(). |
| * So we don't call vfp_access_check() and the callers must handle this. |
| */ |
| if (regno != ARM_VFP_FPCXT_NS && !vfp_access_check(s)) { |
| return FPSysRegCheckDone; |
| } |
| return FPSysRegCheckContinue; |
| } |
| |
| static void gen_branch_fpInactive(DisasContext *s, TCGCond cond, |
| TCGLabel *label) |
| { |
| /* |
| * FPCXT_NS is a special case: it has specific handling for |
| * "current FP state is inactive", and must do the PreserveFPState() |
| * but not the usual full set of actions done by ExecuteFPCheck(). |
| * We don't have a TB flag that matches the fpInactive check, so we |
| * do it at runtime as we don't expect FPCXT_NS accesses to be frequent. |
| * |
| * Emit code that checks fpInactive and does a conditional |
| * branch to label based on it: |
| * if cond is TCG_COND_NE then branch if fpInactive != 0 (ie if inactive) |
| * if cond is TCG_COND_EQ then branch if fpInactive == 0 (ie if active) |
| */ |
| assert(cond == TCG_COND_EQ || cond == TCG_COND_NE); |
| |
| /* fpInactive = FPCCR_NS.ASPEN == 1 && CONTROL.FPCA == 0 */ |
| TCGv_i32 aspen, fpca; |
| aspen = load_cpu_field(v7m.fpccr[M_REG_NS]); |
| fpca = load_cpu_field(v7m.control[M_REG_S]); |
| tcg_gen_andi_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); |
| tcg_gen_xori_i32(aspen, aspen, R_V7M_FPCCR_ASPEN_MASK); |
| tcg_gen_andi_i32(fpca, fpca, R_V7M_CONTROL_FPCA_MASK); |
| tcg_gen_or_i32(fpca, fpca, aspen); |
| tcg_gen_brcondi_i32(tcg_invert_cond(cond), fpca, 0, label); |
| } |
| |
| static bool gen_M_fp_sysreg_write(DisasContext *s, int regno, |
| fp_sysreg_loadfn *loadfn, |
| void *opaque) |
| { |
| /* Do a write to an M-profile floating point system register */ |
| TCGv_i32 tmp; |
| TCGLabel *lab_end = NULL; |
| |
| switch (fp_sysreg_checks(s, regno)) { |
| case FPSysRegCheckFailed: |
| return false; |
| case FPSysRegCheckDone: |
| return true; |
| case FPSysRegCheckContinue: |
| break; |
| } |
| |
| switch (regno) { |
| case ARM_VFP_FPSCR: |
| tmp = loadfn(s, opaque, true); |
| gen_helper_vfp_set_fpscr(cpu_env, tmp); |
| gen_lookup_tb(s); |
| break; |
| case ARM_VFP_FPSCR_NZCVQC: |
| { |
| TCGv_i32 fpscr; |
| tmp = loadfn(s, opaque, true); |
| if (dc_isar_feature(aa32_mve, s)) { |
| /* QC is only present for MVE; otherwise RES0 */ |
| TCGv_i32 qc = tcg_temp_new_i32(); |
| tcg_gen_andi_i32(qc, tmp, FPCR_QC); |
| /* |
| * The 4 vfp.qc[] fields need only be "zero" vs "non-zero"; |
| * here writing the same value into all elements is simplest. |
| */ |
| tcg_gen_gvec_dup_i32(MO_32, offsetof(CPUARMState, vfp.qc), |
| 16, 16, qc); |
| } |
| tcg_gen_andi_i32(tmp, tmp, FPCR_NZCV_MASK); |
| fpscr = load_cpu_field(vfp.xregs[ARM_VFP_FPSCR]); |
| tcg_gen_andi_i32(fpscr, fpscr, ~FPCR_NZCV_MASK); |
| tcg_gen_or_i32(fpscr, fpscr, tmp); |
| store_cpu_field(fpscr, vfp.xregs[ARM_VFP_FPSCR]); |
| break; |
| } |
| case ARM_VFP_FPCXT_NS: |
| { |
| TCGLabel *lab_active = gen_new_label(); |
| |
| lab_end = gen_new_label(); |
| gen_branch_fpInactive(s, TCG_COND_EQ, lab_active); |
| /* |
| * fpInactive case: write is a NOP, so only do side effects |
| * like register writeback before we branch to end |
| */ |
| loadfn(s, opaque, false); |
| tcg_gen_br(lab_end); |
| |
| gen_set_label(lab_active); |
| /* |
| * !fpInactive: if FPU disabled, take NOCP exception; |
| * otherwise PreserveFPState(), and then FPCXT_NS writes |
| * behave the same as FPCXT_S writes. |
| */ |
| if (!vfp_access_check_m(s, true)) { |
| /* |
| * This was only a conditional exception, so override |
| * gen_exception_insn_el()'s default to DISAS_NORETURN |
| */ |
| s->base.is_jmp = DISAS_NEXT; |
| break; |
| } |
| } |
| /* fall through */ |
| case ARM_VFP_FPCXT_S: |
| { |
| TCGv_i32 sfpa, control; |
| /* |
| * Set FPSCR and CONTROL.SFPA from value; the new FPSCR takes |
| * bits [27:0] from value and zeroes bits [31:28]. |
| */ |
| tmp = loadfn(s, opaque, true); |
| sfpa = tcg_temp_new_i32(); |
| tcg_gen_shri_i32(sfpa, tmp, 31); |
| control = load_cpu_field(v7m.control[M_REG_S]); |
| tcg_gen_deposit_i32(control, control, sfpa, |
| R_V7M_CONTROL_SFPA_SHIFT, 1); |
| store_cpu_field(control, v7m.control[M_REG_S]); |
| tcg_gen_andi_i32(tmp, tmp, ~FPCR_NZCV_MASK); |
| gen_helper_vfp_set_fpscr(cpu_env, tmp); |
| s->base.is_jmp = DISAS_UPDATE_NOCHAIN; |
| break; |
| } |
| case ARM_VFP_VPR: |
| /* Behaves as NOP if not privileged */ |
| if (IS_USER(s)) { |
| loadfn(s, opaque, false); |
| break; |
| } |
| tmp = loadfn(s, opaque, true); |
| store_cpu_field(tmp, v7m.vpr); |
| s->base.is_jmp = DISAS_UPDATE_NOCHAIN; |
| break; |
| case ARM_VFP_P0: |
| { |
| TCGv_i32 vpr; |
| tmp = loadfn(s, opaque, true); |
| vpr = load_cpu_field(v7m.vpr); |
| tcg_gen_deposit_i32(vpr, vpr, tmp, |
| R_V7M_VPR_P0_SHIFT, R_V7M_VPR_P0_LENGTH); |
| store_cpu_field(vpr, v7m.vpr); |
| s->base.is_jmp = DISAS_UPDATE_NOCHAIN; |
| break; |
| } |
| default: |
| g_assert_not_reached(); |
| } |
| if (lab_end) { |
| gen_set_label(lab_end); |
| } |
| return true; |
| } |
| |
| static bool gen_M_fp_sysreg_read(DisasContext *s, int regno, |
| fp_sysreg_storefn *storefn, |
| void *opaque) |
| { |
| /* Do a read from an M-profile floating point system register */ |
| TCGv_i32 tmp; |
| TCGLabel *lab_end = NULL; |
| bool lookup_tb = false; |
| |
| switch (fp_sysreg_checks(s, regno)) { |
| case FPSysRegCheckFailed: |
| return false; |
| case FPSysRegCheckDone: |
| return true; |
| case FPSysRegCheckContinue: |
| break; |
| } |
| |
| if (regno == ARM_VFP_FPSCR_NZCVQC && !dc_isar_feature(aa32_mve, s)) { |
| /* QC is RES0 without MVE, so NZCVQC simplifies to NZCV */ |
| regno = QEMU_VFP_FPSCR_NZCV; |
| } |
| |
| switch (regno) { |
| case ARM_VFP_FPSCR: |
| tmp = tcg_temp_new_i32(); |
| gen_helper_vfp_get_fpscr(tmp, cpu_env); |
| storefn(s, opaque, tmp, true); |
| break; |
| case ARM_VFP_FPSCR_NZCVQC: |
| tmp = tcg_temp_new_i32(); |
| gen_helper_vfp_get_fpscr(tmp, cpu_env); |
| tcg_gen_andi_i32(tmp, tmp, FPCR_NZCVQC_MASK); |
| storefn(s, opaque, tmp, true); |
| break; |
| case QEMU_VFP_FPSCR_NZCV: |
| /* |
| * Read just NZCV; this is a special case to avoid the |
| * helper call for the "VMRS to CPSR.NZCV" insn. |
| */ |
| tmp = load_cpu_field(vfp.xregs[ARM_VFP_FPSCR]); |
| tcg_gen_andi_i32(tmp, tmp, FPCR_NZCV_MASK); |
| storefn(s, opaque, tmp, true); |
| break; |
| case ARM_VFP_FPCXT_S: |
| { |
| TCGv_i32 control, sfpa, fpscr; |
| /* Bits [27:0] from FPSCR, bit [31] from CONTROL.SFPA */ |
| tmp = tcg_temp_new_i32(); |
| sfpa = tcg_temp_new_i32(); |
| gen_helper_vfp_get_fpscr(tmp, cpu_env); |
| tcg_gen_andi_i32(tmp, tmp, ~FPCR_NZCV_MASK); |
| control = load_cpu_field(v7m.control[M_REG_S]); |
| tcg_gen_andi_i32(sfpa, control, R_V7M_CONTROL_SFPA_MASK); |
| tcg_gen_shli_i32(sfpa, sfpa, 31 - R_V7M_CONTROL_SFPA_SHIFT); |
| tcg_gen_or_i32(tmp, tmp, sfpa); |
| /* |
| * Store result before updating FPSCR etc, in case |
| * it is a memory write which causes an exception. |
| */ |
| storefn(s, opaque, tmp, true); |
| /* |
| * Now we must reset FPSCR from FPDSCR_NS, and clear |
| * CONTROL.SFPA; so we'll end the TB here. |
| */ |
| tcg_gen_andi_i32(control, control, ~R_V7M_CONTROL_SFPA_MASK); |
| store_cpu_field(control, v7m.control[M_REG_S]); |
| fpscr = load_cpu_field(v7m.fpdscr[M_REG_NS]); |
| gen_helper_vfp_set_fpscr(cpu_env, fpscr); |
| lookup_tb = true; |
| break; |
| } |
| case ARM_VFP_FPCXT_NS: |
| { |
| TCGv_i32 control, sfpa, fpscr, fpdscr; |
| TCGLabel *lab_active = gen_new_label(); |
| |
| lookup_tb = true; |
| |
| gen_branch_fpInactive(s, TCG_COND_EQ, lab_active); |
| /* fpInactive case: reads as FPDSCR_NS */ |
| TCGv_i32 tmp = load_cpu_field(v7m.fpdscr[M_REG_NS]); |
| storefn(s, opaque, tmp, true); |
| lab_end = gen_new_label(); |
| tcg_gen_br(lab_end); |
| |
| gen_set_label(lab_active); |
| /* |
| * !fpInactive: if FPU disabled, take NOCP exception; |
| * otherwise PreserveFPState(), and then FPCXT_NS |
| * reads the same as FPCXT_S. |
| */ |
| if (!vfp_access_check_m(s, true)) { |
| /* |
| * This was only a conditional exception, so override |
| * gen_exception_insn_el()'s default to DISAS_NORETURN |
| */ |
| s->base.is_jmp = DISAS_NEXT; |
| break; |
| } |
| tmp = tcg_temp_new_i32(); |
| sfpa = tcg_temp_new_i32(); |
| fpscr = tcg_temp_new_i32(); |
| gen_helper_vfp_get_fpscr(fpscr, cpu_env); |
| tcg_gen_andi_i32(tmp, fpscr, ~FPCR_NZCV_MASK); |
| control = load_cpu_field(v7m.control[M_REG_S]); |
| tcg_gen_andi_i32(sfpa, control, R_V7M_CONTROL_SFPA_MASK); |
| tcg_gen_shli_i32(sfpa, sfpa, 31 - R_V7M_CONTROL_SFPA_SHIFT); |
| tcg_gen_or_i32(tmp, tmp, sfpa); |
| /* Store result before updating FPSCR, in case it faults */ |
| storefn(s, opaque, tmp, true); |
| /* If SFPA is zero then set FPSCR from FPDSCR_NS */ |
| fpdscr = load_cpu_field(v7m.fpdscr[M_REG_NS]); |
| tcg_gen_movcond_i32(TCG_COND_EQ, fpscr, sfpa, tcg_constant_i32(0), |
| fpdscr, fpscr); |
| gen_helper_vfp_set_fpscr(cpu_env, fpscr); |
| break; |
| } |
| case ARM_VFP_VPR: |
| /* Behaves as NOP if not privileged */ |
| if (IS_USER(s)) { |
| storefn(s, opaque, NULL, false); |
| break; |
| } |
| tmp = load_cpu_field(v7m.vpr); |
| storefn(s, opaque, tmp, true); |
| break; |
| case ARM_VFP_P0: |
| tmp = load_cpu_field(v7m.vpr); |
| tcg_gen_extract_i32(tmp, tmp, R_V7M_VPR_P0_SHIFT, R_V7M_VPR_P0_LENGTH); |
| storefn(s, opaque, tmp, true); |
| break; |
| default: |
| g_assert_not_reached(); |
| } |
| |
| if (lab_end) { |
| gen_set_label(lab_end); |
| } |
| if (lookup_tb) { |
| gen_lookup_tb(s); |
| } |
| return true; |
| } |
| |
| static void fp_sysreg_to_gpr(DisasContext *s, void *opaque, TCGv_i32 value, |
| bool do_access) |
| { |
| arg_VMSR_VMRS *a = opaque; |
| |
| if (!do_access) { |
| return; |
| } |
| |
| if (a->rt == 15) { |
| /* Set the 4 flag bits in the CPSR */ |
| gen_set_nzcv(value); |
| } else { |
| store_reg(s, a->rt, value); |
| } |
| } |
| |
| static TCGv_i32 gpr_to_fp_sysreg(DisasContext *s, void *opaque, bool do_access) |
| { |
| arg_VMSR_VMRS *a = opaque; |
| |
| if (!do_access) { |
| return NULL; |
| } |
| return load_reg(s, a->rt); |
| } |
| |
| static bool trans_VMSR_VMRS(DisasContext *s, arg_VMSR_VMRS *a) |
| { |
| /* |
| * Accesses to R15 are UNPREDICTABLE; we choose to undef. |
| * FPSCR -> r15 is a special case which writes to the PSR flags; |
| * set a->reg to a special value to tell gen_M_fp_sysreg_read() |
| * we only care about the top 4 bits of FPSCR there. |
| */ |
| if (a->rt == 15) { |
| if (a->l && a->reg == ARM_VFP_FPSCR) { |
| a->reg = QEMU_VFP_FPSCR_NZCV; |
| } else { |
| return false; |
| } |
| } |
| |
| if (a->l) { |
| /* VMRS, move FP system register to gp register */ |
| return gen_M_fp_sysreg_read(s, a->reg, fp_sysreg_to_gpr, a); |
| } else { |
| /* VMSR, move gp register to FP system register */ |
| return gen_M_fp_sysreg_write(s, a->reg, gpr_to_fp_sysreg, a); |
| } |
| } |
| |
| static void fp_sysreg_to_memory(DisasContext *s, void *opaque, TCGv_i32 value, |
| bool do_access) |
| { |
| arg_vldr_sysreg *a = opaque; |
| uint32_t offset = a->imm; |
| TCGv_i32 addr; |
| |
| if (!a->a) { |
| offset = -offset; |
| } |
| |
| if (!do_access && !a->w) { |
| return; |
| } |
| |
| addr = load_reg(s, a->rn); |
| if (a->p) { |
| tcg_gen_addi_i32(addr, addr, offset); |
| } |
| |
| if (s->v8m_stackcheck && a->rn == 13 && a->w) { |
| gen_helper_v8m_stackcheck(cpu_env, addr); |
| } |
| |
| if (do_access) { |
| gen_aa32_st_i32(s, value, addr, get_mem_index(s), |
| MO_UL | MO_ALIGN | s->be_data); |
| } |
| |
| if (a->w) { |
| /* writeback */ |
| if (!a->p) { |
| tcg_gen_addi_i32(addr, addr, offset); |
| } |
| store_reg(s, a->rn, addr); |
| } |
| } |
| |
| static TCGv_i32 memory_to_fp_sysreg(DisasContext *s, void *opaque, |
| bool do_access) |
| { |
| arg_vldr_sysreg *a = opaque; |
| uint32_t offset = a->imm; |
| TCGv_i32 addr; |
| TCGv_i32 value = NULL; |
| |
| if (!a->a) { |
| offset = -offset; |
| } |
| |
| if (!do_access && !a->w) { |
| return NULL; |
| } |
| |
| addr = load_reg(s, a->rn); |
| if (a->p) { |
| tcg_gen_addi_i32(addr, addr, offset); |
| } |
| |
| if (s->v8m_stackcheck && a->rn == 13 && a->w) { |
| gen_helper_v8m_stackcheck(cpu_env, addr); |
| } |
| |
| if (do_access) { |
| value = tcg_temp_new_i32(); |
| gen_aa32_ld_i32(s, value, addr, get_mem_index(s), |
| MO_UL | MO_ALIGN | s->be_data); |
| } |
| |
| if (a->w) { |
| /* writeback */ |
| if (!a->p) { |
| tcg_gen_addi_i32(addr, addr, offset); |
| } |
| store_reg(s, a->rn, addr); |
| } |
| return value; |
| } |
| |
| static bool trans_VLDR_sysreg(DisasContext *s, arg_vldr_sysreg *a) |
| { |
| if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { |
| return false; |
| } |
| if (a->rn == 15) { |
| return false; |
| } |
| return gen_M_fp_sysreg_write(s, a->reg, memory_to_fp_sysreg, a); |
| } |
| |
| static bool trans_VSTR_sysreg(DisasContext *s, arg_vldr_sysreg *a) |
| { |
| if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { |
| return false; |
| } |
| if (a->rn == 15) { |
| return false; |
| } |
| return gen_M_fp_sysreg_read(s, a->reg, fp_sysreg_to_memory, a); |
| } |
| |
| static bool trans_NOCP(DisasContext *s, arg_nocp *a) |
| { |
| /* |
| * Handle M-profile early check for disabled coprocessor: |
| * all we need to do here is emit the NOCP exception if |
| * the coprocessor is disabled. Otherwise we return false |
| * and the real VFP/etc decode will handle the insn. |
| */ |
| assert(arm_dc_feature(s, ARM_FEATURE_M)); |
| |
| if (a->cp == 11) { |
| a->cp = 10; |
| } |
| if (arm_dc_feature(s, ARM_FEATURE_V8_1M) && |
| (a->cp == 8 || a->cp == 9 || a->cp == 14 || a->cp == 15)) { |
| /* in v8.1M cp 8, 9, 14, 15 also are governed by the cp10 enable */ |
| a->cp = 10; |
| } |
| |
| if (a->cp != 10) { |
| gen_exception_insn(s, 0, EXCP_NOCP, syn_uncategorized()); |
| return true; |
| } |
| |
| if (s->fp_excp_el != 0) { |
| gen_exception_insn_el(s, 0, EXCP_NOCP, |
| syn_uncategorized(), s->fp_excp_el); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| static bool trans_NOCP_8_1(DisasContext *s, arg_nocp *a) |
| { |
| /* This range needs a coprocessor check for v8.1M and later only */ |
| if (!arm_dc_feature(s, ARM_FEATURE_V8_1M)) { |
| return false; |
| } |
| return trans_NOCP(s, a); |
| } |
