| /* |
| * ARM debug helpers. |
| * |
| * This code is licensed under the GNU GPL v2 or later. |
| * |
| * SPDX-License-Identifier: GPL-2.0-or-later |
| */ |
| #include "qemu/osdep.h" |
| #include "qemu/log.h" |
| #include "cpu.h" |
| #include "internals.h" |
| #include "cpregs.h" |
| #include "exec/exec-all.h" |
| #include "exec/helper-proto.h" |
| |
| |
| /* Return the Exception Level targeted by debug exceptions. */ |
| static int arm_debug_target_el(CPUARMState *env) |
| { |
| bool secure = arm_is_secure(env); |
| bool route_to_el2 = false; |
| |
| if (arm_is_el2_enabled(env)) { |
| route_to_el2 = env->cp15.hcr_el2 & HCR_TGE || |
| env->cp15.mdcr_el2 & MDCR_TDE; |
| } |
| |
| if (route_to_el2) { |
| return 2; |
| } else if (arm_feature(env, ARM_FEATURE_EL3) && |
| !arm_el_is_aa64(env, 3) && secure) { |
| return 3; |
| } else { |
| return 1; |
| } |
| } |
| |
| /* |
| * Raise an exception to the debug target el. |
| * Modify syndrome to indicate when origin and target EL are the same. |
| */ |
| G_NORETURN static void |
| raise_exception_debug(CPUARMState *env, uint32_t excp, uint32_t syndrome) |
| { |
| int debug_el = arm_debug_target_el(env); |
| int cur_el = arm_current_el(env); |
| |
| /* |
| * If singlestep is targeting a lower EL than the current one, then |
| * DisasContext.ss_active must be false and we can never get here. |
| * Similarly for watchpoint and breakpoint matches. |
| */ |
| assert(debug_el >= cur_el); |
| syndrome |= (debug_el == cur_el) << ARM_EL_EC_SHIFT; |
| raise_exception(env, excp, syndrome, debug_el); |
| } |
| |
| /* See AArch64.GenerateDebugExceptionsFrom() in ARM ARM pseudocode */ |
| static bool aa64_generate_debug_exceptions(CPUARMState *env) |
| { |
| int cur_el = arm_current_el(env); |
| int debug_el; |
| |
| if (cur_el == 3) { |
| return false; |
| } |
| |
| /* MDCR_EL3.SDD disables debug events from Secure state */ |
| if (arm_is_secure_below_el3(env) |
| && extract32(env->cp15.mdcr_el3, 16, 1)) { |
| return false; |
| } |
| |
| /* |
| * Same EL to same EL debug exceptions need MDSCR_KDE enabled |
| * while not masking the (D)ebug bit in DAIF. |
| */ |
| debug_el = arm_debug_target_el(env); |
| |
| if (cur_el == debug_el) { |
| return extract32(env->cp15.mdscr_el1, 13, 1) |
| && !(env->daif & PSTATE_D); |
| } |
| |
| /* Otherwise the debug target needs to be a higher EL */ |
| return debug_el > cur_el; |
| } |
| |
| static bool aa32_generate_debug_exceptions(CPUARMState *env) |
| { |
| int el = arm_current_el(env); |
| |
| if (el == 0 && arm_el_is_aa64(env, 1)) { |
| return aa64_generate_debug_exceptions(env); |
| } |
| |
| if (arm_is_secure(env)) { |
| int spd; |
| |
| if (el == 0 && (env->cp15.sder & 1)) { |
| /* |
| * SDER.SUIDEN means debug exceptions from Secure EL0 |
| * are always enabled. Otherwise they are controlled by |
| * SDCR.SPD like those from other Secure ELs. |
| */ |
| return true; |
| } |
| |
| spd = extract32(env->cp15.mdcr_el3, 14, 2); |
| switch (spd) { |
| case 1: |
| /* SPD == 0b01 is reserved, but behaves as 0b00. */ |
| case 0: |
| /* |
| * For 0b00 we return true if external secure invasive debug |
| * is enabled. On real hardware this is controlled by external |
| * signals to the core. QEMU always permits debug, and behaves |
| * as if DBGEN, SPIDEN, NIDEN and SPNIDEN are all tied high. |
| */ |
| return true; |
| case 2: |
| return false; |
| case 3: |
| return true; |
| } |
| } |
| |
| return el != 2; |
| } |
| |
| /* |
| * Return true if debugging exceptions are currently enabled. |
| * This corresponds to what in ARM ARM pseudocode would be |
| * if UsingAArch32() then |
| * return AArch32.GenerateDebugExceptions() |
| * else |
| * return AArch64.GenerateDebugExceptions() |
| * We choose to push the if() down into this function for clarity, |
| * since the pseudocode has it at all callsites except for the one in |
| * CheckSoftwareStep(), where it is elided because both branches would |
| * always return the same value. |
| */ |
| bool arm_generate_debug_exceptions(CPUARMState *env) |
| { |
| if ((env->cp15.oslsr_el1 & 1) || (env->cp15.osdlr_el1 & 1)) { |
| return false; |
| } |
| if (is_a64(env)) { |
| return aa64_generate_debug_exceptions(env); |
| } else { |
| return aa32_generate_debug_exceptions(env); |
| } |
| } |
| |
| /* |
| * Is single-stepping active? (Note that the "is EL_D AArch64?" check |
| * implicitly means this always returns false in pre-v8 CPUs.) |
| */ |
| bool arm_singlestep_active(CPUARMState *env) |
| { |
| return extract32(env->cp15.mdscr_el1, 0, 1) |
| && arm_el_is_aa64(env, arm_debug_target_el(env)) |
| && arm_generate_debug_exceptions(env); |
| } |
| |
| /* Return true if the linked breakpoint entry lbn passes its checks */ |
| static bool linked_bp_matches(ARMCPU *cpu, int lbn) |
| { |
| CPUARMState *env = &cpu->env; |
| uint64_t bcr = env->cp15.dbgbcr[lbn]; |
| int brps = arm_num_brps(cpu); |
| int ctx_cmps = arm_num_ctx_cmps(cpu); |
| int bt; |
| uint32_t contextidr; |
| uint64_t hcr_el2; |
| |
| /* |
| * Links to unimplemented or non-context aware breakpoints are |
| * CONSTRAINED UNPREDICTABLE: either behave as if disabled, or |
| * as if linked to an UNKNOWN context-aware breakpoint (in which |
| * case DBGWCR<n>_EL1.LBN must indicate that breakpoint). |
| * We choose the former. |
| */ |
| if (lbn >= brps || lbn < (brps - ctx_cmps)) { |
| return false; |
| } |
| |
| bcr = env->cp15.dbgbcr[lbn]; |
| |
| if (extract64(bcr, 0, 1) == 0) { |
| /* Linked breakpoint disabled : generate no events */ |
| return false; |
| } |
| |
| bt = extract64(bcr, 20, 4); |
| hcr_el2 = arm_hcr_el2_eff(env); |
| |
| switch (bt) { |
| case 3: /* linked context ID match */ |
| switch (arm_current_el(env)) { |
| default: |
| /* Context matches never fire in AArch64 EL3 */ |
| return false; |
| case 2: |
| if (!(hcr_el2 & HCR_E2H)) { |
| /* Context matches never fire in EL2 without E2H enabled. */ |
| return false; |
| } |
| contextidr = env->cp15.contextidr_el[2]; |
| break; |
| case 1: |
| contextidr = env->cp15.contextidr_el[1]; |
| break; |
| case 0: |
| if ((hcr_el2 & (HCR_E2H | HCR_TGE)) == (HCR_E2H | HCR_TGE)) { |
| contextidr = env->cp15.contextidr_el[2]; |
| } else { |
| contextidr = env->cp15.contextidr_el[1]; |
| } |
| break; |
| } |
| break; |
| |
| case 7: /* linked contextidr_el1 match */ |
| contextidr = env->cp15.contextidr_el[1]; |
| break; |
| case 13: /* linked contextidr_el2 match */ |
| contextidr = env->cp15.contextidr_el[2]; |
| break; |
| |
| case 9: /* linked VMID match (reserved if no EL2) */ |
| case 11: /* linked context ID and VMID match (reserved if no EL2) */ |
| case 15: /* linked full context ID match */ |
| default: |
| /* |
| * Links to Unlinked context breakpoints must generate no |
| * events; we choose to do the same for reserved values too. |
| */ |
| return false; |
| } |
| |
| /* |
| * We match the whole register even if this is AArch32 using the |
| * short descriptor format (in which case it holds both PROCID and ASID), |
| * since we don't implement the optional v7 context ID masking. |
| */ |
| return contextidr == (uint32_t)env->cp15.dbgbvr[lbn]; |
| } |
| |
| static bool bp_wp_matches(ARMCPU *cpu, int n, bool is_wp) |
| { |
| CPUARMState *env = &cpu->env; |
| uint64_t cr; |
| int pac, hmc, ssc, wt, lbn; |
| /* |
| * Note that for watchpoints the check is against the CPU security |
| * state, not the S/NS attribute on the offending data access. |
| */ |
| bool is_secure = arm_is_secure(env); |
| int access_el = arm_current_el(env); |
| |
| if (is_wp) { |
| CPUWatchpoint *wp = env->cpu_watchpoint[n]; |
| |
| if (!wp || !(wp->flags & BP_WATCHPOINT_HIT)) { |
| return false; |
| } |
| cr = env->cp15.dbgwcr[n]; |
| if (wp->hitattrs.user) { |
| /* |
| * The LDRT/STRT/LDT/STT "unprivileged access" instructions should |
| * match watchpoints as if they were accesses done at EL0, even if |
| * the CPU is at EL1 or higher. |
| */ |
| access_el = 0; |
| } |
| } else { |
| uint64_t pc = is_a64(env) ? env->pc : env->regs[15]; |
| |
| if (!env->cpu_breakpoint[n] || env->cpu_breakpoint[n]->pc != pc) { |
| return false; |
| } |
| cr = env->cp15.dbgbcr[n]; |
| } |
| /* |
| * The WATCHPOINT_HIT flag guarantees us that the watchpoint is |
| * enabled and that the address and access type match; for breakpoints |
| * we know the address matched; check the remaining fields, including |
| * linked breakpoints. We rely on WCR and BCR having the same layout |
| * for the LBN, SSC, HMC, PAC/PMC and is-linked fields. |
| * Note that some combinations of {PAC, HMC, SSC} are reserved and |
| * must act either like some valid combination or as if the watchpoint |
| * were disabled. We choose the former, and use this together with |
| * the fact that EL3 must always be Secure and EL2 must always be |
| * Non-Secure to simplify the code slightly compared to the full |
| * table in the ARM ARM. |
| */ |
| pac = FIELD_EX64(cr, DBGWCR, PAC); |
| hmc = FIELD_EX64(cr, DBGWCR, HMC); |
| ssc = FIELD_EX64(cr, DBGWCR, SSC); |
| |
| switch (ssc) { |
| case 0: |
| break; |
| case 1: |
| case 3: |
| if (is_secure) { |
| return false; |
| } |
| break; |
| case 2: |
| if (!is_secure) { |
| return false; |
| } |
| break; |
| } |
| |
| switch (access_el) { |
| case 3: |
| case 2: |
| if (!hmc) { |
| return false; |
| } |
| break; |
| case 1: |
| if (extract32(pac, 0, 1) == 0) { |
| return false; |
| } |
| break; |
| case 0: |
| if (extract32(pac, 1, 1) == 0) { |
| return false; |
| } |
| break; |
| default: |
| g_assert_not_reached(); |
| } |
| |
| wt = FIELD_EX64(cr, DBGWCR, WT); |
| lbn = FIELD_EX64(cr, DBGWCR, LBN); |
| |
| if (wt && !linked_bp_matches(cpu, lbn)) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static bool check_watchpoints(ARMCPU *cpu) |
| { |
| CPUARMState *env = &cpu->env; |
| int n; |
| |
| /* |
| * If watchpoints are disabled globally or we can't take debug |
| * exceptions here then watchpoint firings are ignored. |
| */ |
| if (extract32(env->cp15.mdscr_el1, 15, 1) == 0 |
| || !arm_generate_debug_exceptions(env)) { |
| return false; |
| } |
| |
| for (n = 0; n < ARRAY_SIZE(env->cpu_watchpoint); n++) { |
| if (bp_wp_matches(cpu, n, true)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool arm_debug_check_breakpoint(CPUState *cs) |
| { |
| ARMCPU *cpu = ARM_CPU(cs); |
| CPUARMState *env = &cpu->env; |
| target_ulong pc; |
| int n; |
| |
| /* |
| * If breakpoints are disabled globally or we can't take debug |
| * exceptions here then breakpoint firings are ignored. |
| */ |
| if (extract32(env->cp15.mdscr_el1, 15, 1) == 0 |
| || !arm_generate_debug_exceptions(env)) { |
| return false; |
| } |
| |
| /* |
| * Single-step exceptions have priority over breakpoint exceptions. |
| * If single-step state is active-pending, suppress the bp. |
| */ |
| if (arm_singlestep_active(env) && !(env->pstate & PSTATE_SS)) { |
| return false; |
| } |
| |
| /* |
| * PC alignment faults have priority over breakpoint exceptions. |
| */ |
| pc = is_a64(env) ? env->pc : env->regs[15]; |
| if ((is_a64(env) || !env->thumb) && (pc & 3) != 0) { |
| return false; |
| } |
| |
| /* |
| * Instruction aborts have priority over breakpoint exceptions. |
| * TODO: We would need to look up the page for PC and verify that |
| * it is present and executable. |
| */ |
| |
| for (n = 0; n < ARRAY_SIZE(env->cpu_breakpoint); n++) { |
| if (bp_wp_matches(cpu, n, false)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool arm_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp) |
| { |
| /* |
| * Called by core code when a CPU watchpoint fires; need to check if this |
| * is also an architectural watchpoint match. |
| */ |
| ARMCPU *cpu = ARM_CPU(cs); |
| |
| return check_watchpoints(cpu); |
| } |
| |
| /* |
| * Return the FSR value for a debug exception (watchpoint, hardware |
| * breakpoint or BKPT insn) targeting the specified exception level. |
| */ |
| static uint32_t arm_debug_exception_fsr(CPUARMState *env) |
| { |
| ARMMMUFaultInfo fi = { .type = ARMFault_Debug }; |
| int target_el = arm_debug_target_el(env); |
| bool using_lpae = false; |
| |
| if (target_el == 2 || arm_el_is_aa64(env, target_el)) { |
| using_lpae = true; |
| } else { |
| if (arm_feature(env, ARM_FEATURE_LPAE) && |
| (env->cp15.tcr_el[target_el].raw_tcr & TTBCR_EAE)) { |
| using_lpae = true; |
| } |
| } |
| |
| if (using_lpae) { |
| return arm_fi_to_lfsc(&fi); |
| } else { |
| return arm_fi_to_sfsc(&fi); |
| } |
| } |
| |
| void arm_debug_excp_handler(CPUState *cs) |
| { |
| /* |
| * Called by core code when a watchpoint or breakpoint fires; |
| * need to check which one and raise the appropriate exception. |
| */ |
| ARMCPU *cpu = ARM_CPU(cs); |
| CPUARMState *env = &cpu->env; |
| CPUWatchpoint *wp_hit = cs->watchpoint_hit; |
| |
| if (wp_hit) { |
| if (wp_hit->flags & BP_CPU) { |
| bool wnr = (wp_hit->flags & BP_WATCHPOINT_HIT_WRITE) != 0; |
| |
| cs->watchpoint_hit = NULL; |
| |
| env->exception.fsr = arm_debug_exception_fsr(env); |
| env->exception.vaddress = wp_hit->hitaddr; |
| raise_exception_debug(env, EXCP_DATA_ABORT, |
| syn_watchpoint(0, 0, wnr)); |
| } |
| } else { |
| uint64_t pc = is_a64(env) ? env->pc : env->regs[15]; |
| |
| /* |
| * (1) GDB breakpoints should be handled first. |
| * (2) Do not raise a CPU exception if no CPU breakpoint has fired, |
| * since singlestep is also done by generating a debug internal |
| * exception. |
| */ |
| if (cpu_breakpoint_test(cs, pc, BP_GDB) |
| || !cpu_breakpoint_test(cs, pc, BP_CPU)) { |
| return; |
| } |
| |
| env->exception.fsr = arm_debug_exception_fsr(env); |
| /* |
| * FAR is UNKNOWN: clear vaddress to avoid potentially exposing |
| * values to the guest that it shouldn't be able to see at its |
| * exception/security level. |
| */ |
| env->exception.vaddress = 0; |
| raise_exception_debug(env, EXCP_PREFETCH_ABORT, syn_breakpoint(0)); |
| } |
| } |
| |
| /* |
| * Raise an EXCP_BKPT with the specified syndrome register value, |
| * targeting the correct exception level for debug exceptions. |
| */ |
| void HELPER(exception_bkpt_insn)(CPUARMState *env, uint32_t syndrome) |
| { |
| int debug_el = arm_debug_target_el(env); |
| int cur_el = arm_current_el(env); |
| |
| /* FSR will only be used if the debug target EL is AArch32. */ |
| env->exception.fsr = arm_debug_exception_fsr(env); |
| /* |
| * FAR is UNKNOWN: clear vaddress to avoid potentially exposing |
| * values to the guest that it shouldn't be able to see at its |
| * exception/security level. |
| */ |
| env->exception.vaddress = 0; |
| /* |
| * Other kinds of architectural debug exception are ignored if |
| * they target an exception level below the current one (in QEMU |
| * this is checked by arm_generate_debug_exceptions()). Breakpoint |
| * instructions are special because they always generate an exception |
| * to somewhere: if they can't go to the configured debug exception |
| * level they are taken to the current exception level. |
| */ |
| if (debug_el < cur_el) { |
| debug_el = cur_el; |
| } |
| raise_exception(env, EXCP_BKPT, syndrome, debug_el); |
| } |
| |
| void HELPER(exception_swstep)(CPUARMState *env, uint32_t syndrome) |
| { |
| raise_exception_debug(env, EXCP_UDEF, syndrome); |
| } |
| |
| /* |
| * Check for traps to "powerdown debug" registers, which are controlled |
| * by MDCR.TDOSA |
| */ |
| static CPAccessResult access_tdosa(CPUARMState *env, const ARMCPRegInfo *ri, |
| bool isread) |
| { |
| int el = arm_current_el(env); |
| uint64_t mdcr_el2 = arm_mdcr_el2_eff(env); |
| bool mdcr_el2_tdosa = (mdcr_el2 & MDCR_TDOSA) || (mdcr_el2 & MDCR_TDE) || |
| (arm_hcr_el2_eff(env) & HCR_TGE); |
| |
| if (el < 2 && mdcr_el2_tdosa) { |
| return CP_ACCESS_TRAP_EL2; |
| } |
| if (el < 3 && (env->cp15.mdcr_el3 & MDCR_TDOSA)) { |
| return CP_ACCESS_TRAP_EL3; |
| } |
| return CP_ACCESS_OK; |
| } |
| |
| /* |
| * Check for traps to "debug ROM" registers, which are controlled |
| * by MDCR_EL2.TDRA for EL2 but by the more general MDCR_EL3.TDA for EL3. |
| */ |
| static CPAccessResult access_tdra(CPUARMState *env, const ARMCPRegInfo *ri, |
| bool isread) |
| { |
| int el = arm_current_el(env); |
| uint64_t mdcr_el2 = arm_mdcr_el2_eff(env); |
| bool mdcr_el2_tdra = (mdcr_el2 & MDCR_TDRA) || (mdcr_el2 & MDCR_TDE) || |
| (arm_hcr_el2_eff(env) & HCR_TGE); |
| |
| if (el < 2 && mdcr_el2_tdra) { |
| return CP_ACCESS_TRAP_EL2; |
| } |
| if (el < 3 && (env->cp15.mdcr_el3 & MDCR_TDA)) { |
| return CP_ACCESS_TRAP_EL3; |
| } |
| return CP_ACCESS_OK; |
| } |
| |
| /* |
| * Check for traps to general debug registers, which are controlled |
| * by MDCR_EL2.TDA for EL2 and MDCR_EL3.TDA for EL3. |
| */ |
| static CPAccessResult access_tda(CPUARMState *env, const ARMCPRegInfo *ri, |
| bool isread) |
| { |
| int el = arm_current_el(env); |
| uint64_t mdcr_el2 = arm_mdcr_el2_eff(env); |
| bool mdcr_el2_tda = (mdcr_el2 & MDCR_TDA) || (mdcr_el2 & MDCR_TDE) || |
| (arm_hcr_el2_eff(env) & HCR_TGE); |
| |
| if (el < 2 && mdcr_el2_tda) { |
| return CP_ACCESS_TRAP_EL2; |
| } |
| if (el < 3 && (env->cp15.mdcr_el3 & MDCR_TDA)) { |
| return CP_ACCESS_TRAP_EL3; |
| } |
| return CP_ACCESS_OK; |
| } |
| |
| static void oslar_write(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value) |
| { |
| /* |
| * Writes to OSLAR_EL1 may update the OS lock status, which can be |
| * read via a bit in OSLSR_EL1. |
| */ |
| int oslock; |
| |
| if (ri->state == ARM_CP_STATE_AA32) { |
| oslock = (value == 0xC5ACCE55); |
| } else { |
| oslock = value & 1; |
| } |
| |
| env->cp15.oslsr_el1 = deposit32(env->cp15.oslsr_el1, 1, 1, oslock); |
| } |
| |
| static void osdlr_write(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value) |
| { |
| ARMCPU *cpu = env_archcpu(env); |
| /* |
| * Only defined bit is bit 0 (DLK); if Feat_DoubleLock is not |
| * implemented this is RAZ/WI. |
| */ |
| if(arm_feature(env, ARM_FEATURE_AARCH64) |
| ? cpu_isar_feature(aa64_doublelock, cpu) |
| : cpu_isar_feature(aa32_doublelock, cpu)) { |
| env->cp15.osdlr_el1 = value & 1; |
| } |
| } |
| |
| static const ARMCPRegInfo debug_cp_reginfo[] = { |
| /* |
| * DBGDRAR, DBGDSAR: always RAZ since we don't implement memory mapped |
| * debug components. The AArch64 version of DBGDRAR is named MDRAR_EL1; |
| * unlike DBGDRAR it is never accessible from EL0. |
| * DBGDSAR is deprecated and must RAZ from v8 anyway, so it has no AArch64 |
| * accessor. |
| */ |
| { .name = "DBGDRAR", .cp = 14, .crn = 1, .crm = 0, .opc1 = 0, .opc2 = 0, |
| .access = PL0_R, .accessfn = access_tdra, |
| .type = ARM_CP_CONST, .resetvalue = 0 }, |
| { .name = "MDRAR_EL1", .state = ARM_CP_STATE_AA64, |
| .opc0 = 2, .opc1 = 0, .crn = 1, .crm = 0, .opc2 = 0, |
| .access = PL1_R, .accessfn = access_tdra, |
| .type = ARM_CP_CONST, .resetvalue = 0 }, |
| { .name = "DBGDSAR", .cp = 14, .crn = 2, .crm = 0, .opc1 = 0, .opc2 = 0, |
| .access = PL0_R, .accessfn = access_tdra, |
| .type = ARM_CP_CONST, .resetvalue = 0 }, |
| /* Monitor debug system control register; the 32-bit alias is DBGDSCRext. */ |
| { .name = "MDSCR_EL1", .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = 2, .opc2 = 2, |
| .access = PL1_RW, .accessfn = access_tda, |
| .fieldoffset = offsetof(CPUARMState, cp15.mdscr_el1), |
| .resetvalue = 0 }, |
| /* |
| * MDCCSR_EL0[30:29] map to EDSCR[30:29]. Simply RAZ as the external |
| * Debug Communication Channel is not implemented. |
| */ |
| { .name = "MDCCSR_EL0", .state = ARM_CP_STATE_AA64, |
| .opc0 = 2, .opc1 = 3, .crn = 0, .crm = 1, .opc2 = 0, |
| .access = PL0_R, .accessfn = access_tda, |
| .type = ARM_CP_CONST, .resetvalue = 0 }, |
| /* |
| * DBGDSCRint[15,12,5:2] map to MDSCR_EL1[15,12,5:2]. Map all bits as |
| * it is unlikely a guest will care. |
| * We don't implement the configurable EL0 access. |
| */ |
| { .name = "DBGDSCRint", .state = ARM_CP_STATE_AA32, |
| .cp = 14, .opc1 = 0, .crn = 0, .crm = 1, .opc2 = 0, |
| .type = ARM_CP_ALIAS, |
| .access = PL1_R, .accessfn = access_tda, |
| .fieldoffset = offsetof(CPUARMState, cp15.mdscr_el1), }, |
| { .name = "OSLAR_EL1", .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 1, .crm = 0, .opc2 = 4, |
| .access = PL1_W, .type = ARM_CP_NO_RAW, |
| .accessfn = access_tdosa, |
| .writefn = oslar_write }, |
| { .name = "OSLSR_EL1", .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 1, .crm = 1, .opc2 = 4, |
| .access = PL1_R, .resetvalue = 10, |
| .accessfn = access_tdosa, |
| .fieldoffset = offsetof(CPUARMState, cp15.oslsr_el1) }, |
| /* Dummy OSDLR_EL1: 32-bit Linux will read this */ |
| { .name = "OSDLR_EL1", .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 1, .crm = 3, .opc2 = 4, |
| .access = PL1_RW, .accessfn = access_tdosa, |
| .writefn = osdlr_write, |
| .fieldoffset = offsetof(CPUARMState, cp15.osdlr_el1) }, |
| /* |
| * Dummy DBGVCR: Linux wants to clear this on startup, but we don't |
| * implement vector catch debug events yet. |
| */ |
| { .name = "DBGVCR", |
| .cp = 14, .opc1 = 0, .crn = 0, .crm = 7, .opc2 = 0, |
| .access = PL1_RW, .accessfn = access_tda, |
| .type = ARM_CP_NOP }, |
| /* |
| * Dummy DBGVCR32_EL2 (which is only for a 64-bit hypervisor |
| * to save and restore a 32-bit guest's DBGVCR) |
| */ |
| { .name = "DBGVCR32_EL2", .state = ARM_CP_STATE_AA64, |
| .opc0 = 2, .opc1 = 4, .crn = 0, .crm = 7, .opc2 = 0, |
| .access = PL2_RW, .accessfn = access_tda, |
| .type = ARM_CP_NOP | ARM_CP_EL3_NO_EL2_KEEP }, |
| /* |
| * Dummy MDCCINT_EL1, since we don't implement the Debug Communications |
| * Channel but Linux may try to access this register. The 32-bit |
| * alias is DBGDCCINT. |
| */ |
| { .name = "MDCCINT_EL1", .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = 2, .opc2 = 0, |
| .access = PL1_RW, .accessfn = access_tda, |
| .type = ARM_CP_NOP }, |
| }; |
| |
| static const ARMCPRegInfo debug_lpae_cp_reginfo[] = { |
| /* 64 bit access versions of the (dummy) debug registers */ |
| { .name = "DBGDRAR", .cp = 14, .crm = 1, .opc1 = 0, |
| .access = PL0_R, .type = ARM_CP_CONST | ARM_CP_64BIT, .resetvalue = 0 }, |
| { .name = "DBGDSAR", .cp = 14, .crm = 2, .opc1 = 0, |
| .access = PL0_R, .type = ARM_CP_CONST | ARM_CP_64BIT, .resetvalue = 0 }, |
| }; |
| |
| void hw_watchpoint_update(ARMCPU *cpu, int n) |
| { |
| CPUARMState *env = &cpu->env; |
| vaddr len = 0; |
| vaddr wvr = env->cp15.dbgwvr[n]; |
| uint64_t wcr = env->cp15.dbgwcr[n]; |
| int mask; |
| int flags = BP_CPU | BP_STOP_BEFORE_ACCESS; |
| |
| if (env->cpu_watchpoint[n]) { |
| cpu_watchpoint_remove_by_ref(CPU(cpu), env->cpu_watchpoint[n]); |
| env->cpu_watchpoint[n] = NULL; |
| } |
| |
| if (!FIELD_EX64(wcr, DBGWCR, E)) { |
| /* E bit clear : watchpoint disabled */ |
| return; |
| } |
| |
| switch (FIELD_EX64(wcr, DBGWCR, LSC)) { |
| case 0: |
| /* LSC 00 is reserved and must behave as if the wp is disabled */ |
| return; |
| case 1: |
| flags |= BP_MEM_READ; |
| break; |
| case 2: |
| flags |= BP_MEM_WRITE; |
| break; |
| case 3: |
| flags |= BP_MEM_ACCESS; |
| break; |
| } |
| |
| /* |
| * Attempts to use both MASK and BAS fields simultaneously are |
| * CONSTRAINED UNPREDICTABLE; we opt to ignore BAS in this case, |
| * thus generating a watchpoint for every byte in the masked region. |
| */ |
| mask = FIELD_EX64(wcr, DBGWCR, MASK); |
| if (mask == 1 || mask == 2) { |
| /* |
| * Reserved values of MASK; we must act as if the mask value was |
| * some non-reserved value, or as if the watchpoint were disabled. |
| * We choose the latter. |
| */ |
| return; |
| } else if (mask) { |
| /* Watchpoint covers an aligned area up to 2GB in size */ |
| len = 1ULL << mask; |
| /* |
| * If masked bits in WVR are not zero it's CONSTRAINED UNPREDICTABLE |
| * whether the watchpoint fires when the unmasked bits match; we opt |
| * to generate the exceptions. |
| */ |
| wvr &= ~(len - 1); |
| } else { |
| /* Watchpoint covers bytes defined by the byte address select bits */ |
| int bas = FIELD_EX64(wcr, DBGWCR, BAS); |
| int basstart; |
| |
| if (extract64(wvr, 2, 1)) { |
| /* |
| * Deprecated case of an only 4-aligned address. BAS[7:4] are |
| * ignored, and BAS[3:0] define which bytes to watch. |
| */ |
| bas &= 0xf; |
| } |
| |
| if (bas == 0) { |
| /* This must act as if the watchpoint is disabled */ |
| return; |
| } |
| |
| /* |
| * The BAS bits are supposed to be programmed to indicate a contiguous |
| * range of bytes. Otherwise it is CONSTRAINED UNPREDICTABLE whether |
| * we fire for each byte in the word/doubleword addressed by the WVR. |
| * We choose to ignore any non-zero bits after the first range of 1s. |
| */ |
| basstart = ctz32(bas); |
| len = cto32(bas >> basstart); |
| wvr += basstart; |
| } |
| |
| cpu_watchpoint_insert(CPU(cpu), wvr, len, flags, |
| &env->cpu_watchpoint[n]); |
| } |
| |
| void hw_watchpoint_update_all(ARMCPU *cpu) |
| { |
| int i; |
| CPUARMState *env = &cpu->env; |
| |
| /* |
| * Completely clear out existing QEMU watchpoints and our array, to |
| * avoid possible stale entries following migration load. |
| */ |
| cpu_watchpoint_remove_all(CPU(cpu), BP_CPU); |
| memset(env->cpu_watchpoint, 0, sizeof(env->cpu_watchpoint)); |
| |
| for (i = 0; i < ARRAY_SIZE(cpu->env.cpu_watchpoint); i++) { |
| hw_watchpoint_update(cpu, i); |
| } |
| } |
| |
| static void dbgwvr_write(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value) |
| { |
| ARMCPU *cpu = env_archcpu(env); |
| int i = ri->crm; |
| |
| /* |
| * Bits [1:0] are RES0. |
| * |
| * It is IMPLEMENTATION DEFINED whether [63:49] ([63:53] with FEAT_LVA) |
| * are hardwired to the value of bit [48] ([52] with FEAT_LVA), or if |
| * they contain the value written. It is CONSTRAINED UNPREDICTABLE |
| * whether the RESS bits are ignored when comparing an address. |
| * |
| * Therefore we are allowed to compare the entire register, which lets |
| * us avoid considering whether or not FEAT_LVA is actually enabled. |
| */ |
| value &= ~3ULL; |
| |
| raw_write(env, ri, value); |
| hw_watchpoint_update(cpu, i); |
| } |
| |
| static void dbgwcr_write(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value) |
| { |
| ARMCPU *cpu = env_archcpu(env); |
| int i = ri->crm; |
| |
| raw_write(env, ri, value); |
| hw_watchpoint_update(cpu, i); |
| } |
| |
| void hw_breakpoint_update(ARMCPU *cpu, int n) |
| { |
| CPUARMState *env = &cpu->env; |
| uint64_t bvr = env->cp15.dbgbvr[n]; |
| uint64_t bcr = env->cp15.dbgbcr[n]; |
| vaddr addr; |
| int bt; |
| int flags = BP_CPU; |
| |
| if (env->cpu_breakpoint[n]) { |
| cpu_breakpoint_remove_by_ref(CPU(cpu), env->cpu_breakpoint[n]); |
| env->cpu_breakpoint[n] = NULL; |
| } |
| |
| if (!extract64(bcr, 0, 1)) { |
| /* E bit clear : watchpoint disabled */ |
| return; |
| } |
| |
| bt = extract64(bcr, 20, 4); |
| |
| switch (bt) { |
| case 4: /* unlinked address mismatch (reserved if AArch64) */ |
| case 5: /* linked address mismatch (reserved if AArch64) */ |
| qemu_log_mask(LOG_UNIMP, |
| "arm: address mismatch breakpoint types not implemented\n"); |
| return; |
| case 0: /* unlinked address match */ |
| case 1: /* linked address match */ |
| { |
| /* |
| * Bits [1:0] are RES0. |
| * |
| * It is IMPLEMENTATION DEFINED whether bits [63:49] |
| * ([63:53] for FEAT_LVA) are hardwired to a copy of the sign bit |
| * of the VA field ([48] or [52] for FEAT_LVA), or whether the |
| * value is read as written. It is CONSTRAINED UNPREDICTABLE |
| * whether the RESS bits are ignored when comparing an address. |
| * Therefore we are allowed to compare the entire register, which |
| * lets us avoid considering whether FEAT_LVA is actually enabled. |
| * |
| * The BAS field is used to allow setting breakpoints on 16-bit |
| * wide instructions; it is CONSTRAINED UNPREDICTABLE whether |
| * a bp will fire if the addresses covered by the bp and the addresses |
| * covered by the insn overlap but the insn doesn't start at the |
| * start of the bp address range. We choose to require the insn and |
| * the bp to have the same address. The constraints on writing to |
| * BAS enforced in dbgbcr_write mean we have only four cases: |
| * 0b0000 => no breakpoint |
| * 0b0011 => breakpoint on addr |
| * 0b1100 => breakpoint on addr + 2 |
| * 0b1111 => breakpoint on addr |
| * See also figure D2-3 in the v8 ARM ARM (DDI0487A.c). |
| */ |
| int bas = extract64(bcr, 5, 4); |
| addr = bvr & ~3ULL; |
| if (bas == 0) { |
| return; |
| } |
| if (bas == 0xc) { |
| addr += 2; |
| } |
| break; |
| } |
| case 2: /* unlinked context ID match */ |
| case 8: /* unlinked VMID match (reserved if no EL2) */ |
| case 10: /* unlinked context ID and VMID match (reserved if no EL2) */ |
| qemu_log_mask(LOG_UNIMP, |
| "arm: unlinked context breakpoint types not implemented\n"); |
| return; |
| case 9: /* linked VMID match (reserved if no EL2) */ |
| case 11: /* linked context ID and VMID match (reserved if no EL2) */ |
| case 3: /* linked context ID match */ |
| default: |
| /* |
| * We must generate no events for Linked context matches (unless |
| * they are linked to by some other bp/wp, which is handled in |
| * updates for the linking bp/wp). We choose to also generate no events |
| * for reserved values. |
| */ |
| return; |
| } |
| |
| cpu_breakpoint_insert(CPU(cpu), addr, flags, &env->cpu_breakpoint[n]); |
| } |
| |
| void hw_breakpoint_update_all(ARMCPU *cpu) |
| { |
| int i; |
| CPUARMState *env = &cpu->env; |
| |
| /* |
| * Completely clear out existing QEMU breakpoints and our array, to |
| * avoid possible stale entries following migration load. |
| */ |
| cpu_breakpoint_remove_all(CPU(cpu), BP_CPU); |
| memset(env->cpu_breakpoint, 0, sizeof(env->cpu_breakpoint)); |
| |
| for (i = 0; i < ARRAY_SIZE(cpu->env.cpu_breakpoint); i++) { |
| hw_breakpoint_update(cpu, i); |
| } |
| } |
| |
| static void dbgbvr_write(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value) |
| { |
| ARMCPU *cpu = env_archcpu(env); |
| int i = ri->crm; |
| |
| raw_write(env, ri, value); |
| hw_breakpoint_update(cpu, i); |
| } |
| |
| static void dbgbcr_write(CPUARMState *env, const ARMCPRegInfo *ri, |
| uint64_t value) |
| { |
| ARMCPU *cpu = env_archcpu(env); |
| int i = ri->crm; |
| |
| /* |
| * BAS[3] is a read-only copy of BAS[2], and BAS[1] a read-only |
| * copy of BAS[0]. |
| */ |
| value = deposit64(value, 6, 1, extract64(value, 5, 1)); |
| value = deposit64(value, 8, 1, extract64(value, 7, 1)); |
| |
| raw_write(env, ri, value); |
| hw_breakpoint_update(cpu, i); |
| } |
| |
| void define_debug_regs(ARMCPU *cpu) |
| { |
| /* |
| * Define v7 and v8 architectural debug registers. |
| * These are just dummy implementations for now. |
| */ |
| int i; |
| int wrps, brps, ctx_cmps; |
| |
| /* |
| * The Arm ARM says DBGDIDR is optional and deprecated if EL1 cannot |
| * use AArch32. Given that bit 15 is RES1, if the value is 0 then |
| * the register must not exist for this cpu. |
| */ |
| if (cpu->isar.dbgdidr != 0) { |
| ARMCPRegInfo dbgdidr = { |
| .name = "DBGDIDR", .cp = 14, .crn = 0, .crm = 0, |
| .opc1 = 0, .opc2 = 0, |
| .access = PL0_R, .accessfn = access_tda, |
| .type = ARM_CP_CONST, .resetvalue = cpu->isar.dbgdidr, |
| }; |
| define_one_arm_cp_reg(cpu, &dbgdidr); |
| } |
| |
| /* |
| * DBGDEVID is present in the v7 debug architecture if |
| * DBGDIDR.DEVID_imp is 1 (bit 15); from v7.1 and on it is |
| * mandatory (and bit 15 is RES1). DBGDEVID1 and DBGDEVID2 exist |
| * from v7.1 of the debug architecture. Because no fields have yet |
| * been defined in DBGDEVID2 (and quite possibly none will ever |
| * be) we don't define an ARMISARegisters field for it. |
| * These registers exist only if EL1 can use AArch32, but that |
| * happens naturally because they are only PL1 accessible anyway. |
| */ |
| if (extract32(cpu->isar.dbgdidr, 15, 1)) { |
| ARMCPRegInfo dbgdevid = { |
| .name = "DBGDEVID", |
| .cp = 14, .opc1 = 0, .crn = 7, .opc2 = 2, .crn = 7, |
| .access = PL1_R, .accessfn = access_tda, |
| .type = ARM_CP_CONST, .resetvalue = cpu->isar.dbgdevid, |
| }; |
| define_one_arm_cp_reg(cpu, &dbgdevid); |
| } |
| if (cpu_isar_feature(aa32_debugv7p1, cpu)) { |
| ARMCPRegInfo dbgdevid12[] = { |
| { |
| .name = "DBGDEVID1", |
| .cp = 14, .opc1 = 0, .crn = 7, .opc2 = 1, .crn = 7, |
| .access = PL1_R, .accessfn = access_tda, |
| .type = ARM_CP_CONST, .resetvalue = cpu->isar.dbgdevid1, |
| }, { |
| .name = "DBGDEVID2", |
| .cp = 14, .opc1 = 0, .crn = 7, .opc2 = 0, .crn = 7, |
| .access = PL1_R, .accessfn = access_tda, |
| .type = ARM_CP_CONST, .resetvalue = 0, |
| }, |
| }; |
| define_arm_cp_regs(cpu, dbgdevid12); |
| } |
| |
| brps = arm_num_brps(cpu); |
| wrps = arm_num_wrps(cpu); |
| ctx_cmps = arm_num_ctx_cmps(cpu); |
| |
| assert(ctx_cmps <= brps); |
| |
| define_arm_cp_regs(cpu, debug_cp_reginfo); |
| |
| if (arm_feature(&cpu->env, ARM_FEATURE_LPAE)) { |
| define_arm_cp_regs(cpu, debug_lpae_cp_reginfo); |
| } |
| |
| for (i = 0; i < brps; i++) { |
| char *dbgbvr_el1_name = g_strdup_printf("DBGBVR%d_EL1", i); |
| char *dbgbcr_el1_name = g_strdup_printf("DBGBCR%d_EL1", i); |
| ARMCPRegInfo dbgregs[] = { |
| { .name = dbgbvr_el1_name, .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = i, .opc2 = 4, |
| .access = PL1_RW, .accessfn = access_tda, |
| .fieldoffset = offsetof(CPUARMState, cp15.dbgbvr[i]), |
| .writefn = dbgbvr_write, .raw_writefn = raw_write |
| }, |
| { .name = dbgbcr_el1_name, .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = i, .opc2 = 5, |
| .access = PL1_RW, .accessfn = access_tda, |
| .fieldoffset = offsetof(CPUARMState, cp15.dbgbcr[i]), |
| .writefn = dbgbcr_write, .raw_writefn = raw_write |
| }, |
| }; |
| define_arm_cp_regs(cpu, dbgregs); |
| g_free(dbgbvr_el1_name); |
| g_free(dbgbcr_el1_name); |
| } |
| |
| for (i = 0; i < wrps; i++) { |
| char *dbgwvr_el1_name = g_strdup_printf("DBGWVR%d_EL1", i); |
| char *dbgwcr_el1_name = g_strdup_printf("DBGWCR%d_EL1", i); |
| ARMCPRegInfo dbgregs[] = { |
| { .name = dbgwvr_el1_name, .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = i, .opc2 = 6, |
| .access = PL1_RW, .accessfn = access_tda, |
| .fieldoffset = offsetof(CPUARMState, cp15.dbgwvr[i]), |
| .writefn = dbgwvr_write, .raw_writefn = raw_write |
| }, |
| { .name = dbgwcr_el1_name, .state = ARM_CP_STATE_BOTH, |
| .cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = i, .opc2 = 7, |
| .access = PL1_RW, .accessfn = access_tda, |
| .fieldoffset = offsetof(CPUARMState, cp15.dbgwcr[i]), |
| .writefn = dbgwcr_write, .raw_writefn = raw_write |
| }, |
| }; |
| define_arm_cp_regs(cpu, dbgregs); |
| g_free(dbgwvr_el1_name); |
| g_free(dbgwcr_el1_name); |
| } |
| } |
| |
| #if !defined(CONFIG_USER_ONLY) |
| |
| vaddr arm_adjust_watchpoint_address(CPUState *cs, vaddr addr, int len) |
| { |
| ARMCPU *cpu = ARM_CPU(cs); |
| CPUARMState *env = &cpu->env; |
| |
| /* |
| * In BE32 system mode, target memory is stored byteswapped (on a |
| * little-endian host system), and by the time we reach here (via an |
| * opcode helper) the addresses of subword accesses have been adjusted |
| * to account for that, which means that watchpoints will not match. |
| * Undo the adjustment here. |
| */ |
| if (arm_sctlr_b(env)) { |
| if (len == 1) { |
| addr ^= 3; |
| } else if (len == 2) { |
| addr ^= 2; |
| } |
| } |
| |
| return addr; |
| } |
| |
| #endif |
