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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/target-arm/op_helper.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/target-arm/op_helper.c')
-rw-r--r--qemu/target-arm/op_helper.c971
1 files changed, 971 insertions, 0 deletions
diff --git a/qemu/target-arm/op_helper.c b/qemu/target-arm/op_helper.c
new file mode 100644
index 000000000..663c05d1d
--- /dev/null
+++ b/qemu/target-arm/op_helper.c
@@ -0,0 +1,971 @@
+/*
+ * ARM helper routines
+ *
+ * Copyright (c) 2005-2007 CodeSourcery, LLC
+ *
+ * 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 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 "cpu.h"
+#include "exec/helper-proto.h"
+#include "internals.h"
+#include "exec/cpu_ldst.h"
+
+#define SIGNBIT (uint32_t)0x80000000
+#define SIGNBIT64 ((uint64_t)1 << 63)
+
+static void raise_exception(CPUARMState *env, uint32_t excp,
+ uint32_t syndrome, uint32_t target_el)
+{
+ CPUState *cs = CPU(arm_env_get_cpu(env));
+
+ assert(!excp_is_internal(excp));
+ cs->exception_index = excp;
+ env->exception.syndrome = syndrome;
+ env->exception.target_el = target_el;
+ cpu_loop_exit(cs);
+}
+
+static int exception_target_el(CPUARMState *env)
+{
+ int target_el = MAX(1, arm_current_el(env));
+
+ /* No such thing as secure EL1 if EL3 is aarch32, so update the target EL
+ * to EL3 in this case.
+ */
+ if (arm_is_secure(env) && !arm_el_is_aa64(env, 3) && target_el == 1) {
+ target_el = 3;
+ }
+
+ return target_el;
+}
+
+uint32_t HELPER(neon_tbl)(CPUARMState *env, uint32_t ireg, uint32_t def,
+ uint32_t rn, uint32_t maxindex)
+{
+ uint32_t val;
+ uint32_t tmp;
+ int index;
+ int shift;
+ uint64_t *table;
+ table = (uint64_t *)&env->vfp.regs[rn];
+ val = 0;
+ for (shift = 0; shift < 32; shift += 8) {
+ index = (ireg >> shift) & 0xff;
+ if (index < maxindex) {
+ tmp = (table[index >> 3] >> ((index & 7) << 3)) & 0xff;
+ val |= tmp << shift;
+ } else {
+ val |= def & (0xff << shift);
+ }
+ }
+ return val;
+}
+
+#if !defined(CONFIG_USER_ONLY)
+
+/* try to fill the TLB and return an exception if error. If retaddr is
+ * NULL, it means that the function was called in C code (i.e. not
+ * from generated code or from helper.c)
+ */
+void tlb_fill(CPUState *cs, target_ulong addr, int is_write, int mmu_idx,
+ uintptr_t retaddr)
+{
+ bool ret;
+ uint32_t fsr = 0;
+
+ ret = arm_tlb_fill(cs, addr, is_write, mmu_idx, &fsr);
+ if (unlikely(ret)) {
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ uint32_t syn, exc;
+ bool same_el = (arm_current_el(env) != 0);
+
+ if (retaddr) {
+ /* now we have a real cpu fault */
+ cpu_restore_state(cs, retaddr);
+ }
+
+ /* AArch64 syndrome does not have an LPAE bit */
+ syn = fsr & ~(1 << 9);
+
+ /* For insn and data aborts we assume there is no instruction syndrome
+ * information; this is always true for exceptions reported to EL1.
+ */
+ if (is_write == 2) {
+ syn = syn_insn_abort(same_el, 0, 0, syn);
+ exc = EXCP_PREFETCH_ABORT;
+ } else {
+ syn = syn_data_abort(same_el, 0, 0, 0, is_write == 1, syn);
+ if (is_write == 1 && arm_feature(env, ARM_FEATURE_V6)) {
+ fsr |= (1 << 11);
+ }
+ exc = EXCP_DATA_ABORT;
+ }
+
+ env->exception.vaddress = addr;
+ env->exception.fsr = fsr;
+ raise_exception(env, exc, syn, exception_target_el(env));
+ }
+}
+#endif
+
+uint32_t HELPER(add_setq)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+ uint32_t res = a + b;
+ if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT))
+ env->QF = 1;
+ return res;
+}
+
+uint32_t HELPER(add_saturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+ uint32_t res = a + b;
+ if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT)) {
+ env->QF = 1;
+ res = ~(((int32_t)a >> 31) ^ SIGNBIT);
+ }
+ return res;
+}
+
+uint32_t HELPER(sub_saturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+ uint32_t res = a - b;
+ if (((res ^ a) & SIGNBIT) && ((a ^ b) & SIGNBIT)) {
+ env->QF = 1;
+ res = ~(((int32_t)a >> 31) ^ SIGNBIT);
+ }
+ return res;
+}
+
+uint32_t HELPER(double_saturate)(CPUARMState *env, int32_t val)
+{
+ uint32_t res;
+ if (val >= 0x40000000) {
+ res = ~SIGNBIT;
+ env->QF = 1;
+ } else if (val <= (int32_t)0xc0000000) {
+ res = SIGNBIT;
+ env->QF = 1;
+ } else {
+ res = val << 1;
+ }
+ return res;
+}
+
+uint32_t HELPER(add_usaturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+ uint32_t res = a + b;
+ if (res < a) {
+ env->QF = 1;
+ res = ~0;
+ }
+ return res;
+}
+
+uint32_t HELPER(sub_usaturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+ uint32_t res = a - b;
+ if (res > a) {
+ env->QF = 1;
+ res = 0;
+ }
+ return res;
+}
+
+/* Signed saturation. */
+static inline uint32_t do_ssat(CPUARMState *env, int32_t val, int shift)
+{
+ int32_t top;
+ uint32_t mask;
+
+ top = val >> shift;
+ mask = (1u << shift) - 1;
+ if (top > 0) {
+ env->QF = 1;
+ return mask;
+ } else if (top < -1) {
+ env->QF = 1;
+ return ~mask;
+ }
+ return val;
+}
+
+/* Unsigned saturation. */
+static inline uint32_t do_usat(CPUARMState *env, int32_t val, int shift)
+{
+ uint32_t max;
+
+ max = (1u << shift) - 1;
+ if (val < 0) {
+ env->QF = 1;
+ return 0;
+ } else if (val > max) {
+ env->QF = 1;
+ return max;
+ }
+ return val;
+}
+
+/* Signed saturate. */
+uint32_t HELPER(ssat)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+ return do_ssat(env, x, shift);
+}
+
+/* Dual halfword signed saturate. */
+uint32_t HELPER(ssat16)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+ uint32_t res;
+
+ res = (uint16_t)do_ssat(env, (int16_t)x, shift);
+ res |= do_ssat(env, ((int32_t)x) >> 16, shift) << 16;
+ return res;
+}
+
+/* Unsigned saturate. */
+uint32_t HELPER(usat)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+ return do_usat(env, x, shift);
+}
+
+/* Dual halfword unsigned saturate. */
+uint32_t HELPER(usat16)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+ uint32_t res;
+
+ res = (uint16_t)do_usat(env, (int16_t)x, shift);
+ res |= do_usat(env, ((int32_t)x) >> 16, shift) << 16;
+ return res;
+}
+
+/* Function checks whether WFx (WFI/WFE) instructions are set up to be trapped.
+ * The function returns the target EL (1-3) if the instruction is to be trapped;
+ * otherwise it returns 0 indicating it is not trapped.
+ */
+static inline int check_wfx_trap(CPUARMState *env, bool is_wfe)
+{
+ int cur_el = arm_current_el(env);
+ uint64_t mask;
+
+ /* If we are currently in EL0 then we need to check if SCTLR is set up for
+ * WFx instructions being trapped to EL1. These trap bits don't exist in v7.
+ */
+ if (cur_el < 1 && arm_feature(env, ARM_FEATURE_V8)) {
+ int target_el;
+
+ mask = is_wfe ? SCTLR_nTWE : SCTLR_nTWI;
+ if (arm_is_secure_below_el3(env) && !arm_el_is_aa64(env, 3)) {
+ /* Secure EL0 and Secure PL1 is at EL3 */
+ target_el = 3;
+ } else {
+ target_el = 1;
+ }
+
+ if (!(env->cp15.sctlr_el[target_el] & mask)) {
+ return target_el;
+ }
+ }
+
+ /* We are not trapping to EL1; trap to EL2 if HCR_EL2 requires it
+ * No need for ARM_FEATURE check as if HCR_EL2 doesn't exist the
+ * bits will be zero indicating no trap.
+ */
+ if (cur_el < 2 && !arm_is_secure(env)) {
+ mask = (is_wfe) ? HCR_TWE : HCR_TWI;
+ if (env->cp15.hcr_el2 & mask) {
+ return 2;
+ }
+ }
+
+ /* We are not trapping to EL1 or EL2; trap to EL3 if SCR_EL3 requires it */
+ if (cur_el < 3) {
+ mask = (is_wfe) ? SCR_TWE : SCR_TWI;
+ if (env->cp15.scr_el3 & mask) {
+ return 3;
+ }
+ }
+
+ return 0;
+}
+
+void HELPER(wfi)(CPUARMState *env)
+{
+ CPUState *cs = CPU(arm_env_get_cpu(env));
+ int target_el = check_wfx_trap(env, false);
+
+ if (cpu_has_work(cs)) {
+ /* Don't bother to go into our "low power state" if
+ * we would just wake up immediately.
+ */
+ return;
+ }
+
+ if (target_el) {
+ env->pc -= 4;
+ raise_exception(env, EXCP_UDEF, syn_wfx(1, 0xe, 0), target_el);
+ }
+
+ cs->exception_index = EXCP_HLT;
+ cs->halted = 1;
+ cpu_loop_exit(cs);
+}
+
+void HELPER(wfe)(CPUARMState *env)
+{
+ /* This is a hint instruction that is semantically different
+ * from YIELD even though we currently implement it identically.
+ * Don't actually halt the CPU, just yield back to top
+ * level loop. This is not going into a "low power state"
+ * (ie halting until some event occurs), so we never take
+ * a configurable trap to a different exception level.
+ */
+ HELPER(yield)(env);
+}
+
+void HELPER(yield)(CPUARMState *env)
+{
+ ARMCPU *cpu = arm_env_get_cpu(env);
+ CPUState *cs = CPU(cpu);
+
+ /* This is a non-trappable hint instruction that generally indicates
+ * that the guest is currently busy-looping. Yield control back to the
+ * top level loop so that a more deserving VCPU has a chance to run.
+ */
+ cs->exception_index = EXCP_YIELD;
+ cpu_loop_exit(cs);
+}
+
+/* Raise an internal-to-QEMU exception. This is limited to only
+ * those EXCP values which are special cases for QEMU to interrupt
+ * execution and not to be used for exceptions which are passed to
+ * the guest (those must all have syndrome information and thus should
+ * use exception_with_syndrome).
+ */
+void HELPER(exception_internal)(CPUARMState *env, uint32_t excp)
+{
+ CPUState *cs = CPU(arm_env_get_cpu(env));
+
+ assert(excp_is_internal(excp));
+ cs->exception_index = excp;
+ cpu_loop_exit(cs);
+}
+
+/* Raise an exception with the specified syndrome register value */
+void HELPER(exception_with_syndrome)(CPUARMState *env, uint32_t excp,
+ uint32_t syndrome, uint32_t target_el)
+{
+ raise_exception(env, excp, syndrome, target_el);
+}
+
+uint32_t HELPER(cpsr_read)(CPUARMState *env)
+{
+ return cpsr_read(env) & ~(CPSR_EXEC | CPSR_RESERVED);
+}
+
+void HELPER(cpsr_write)(CPUARMState *env, uint32_t val, uint32_t mask)
+{
+ cpsr_write(env, val, mask);
+}
+
+/* Access to user mode registers from privileged modes. */
+uint32_t HELPER(get_user_reg)(CPUARMState *env, uint32_t regno)
+{
+ uint32_t val;
+
+ if (regno == 13) {
+ val = env->banked_r13[0];
+ } else if (regno == 14) {
+ val = env->banked_r14[0];
+ } else if (regno >= 8
+ && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
+ val = env->usr_regs[regno - 8];
+ } else {
+ val = env->regs[regno];
+ }
+ return val;
+}
+
+void HELPER(set_user_reg)(CPUARMState *env, uint32_t regno, uint32_t val)
+{
+ if (regno == 13) {
+ env->banked_r13[0] = val;
+ } else if (regno == 14) {
+ env->banked_r14[0] = val;
+ } else if (regno >= 8
+ && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
+ env->usr_regs[regno - 8] = val;
+ } else {
+ env->regs[regno] = val;
+ }
+}
+
+void HELPER(access_check_cp_reg)(CPUARMState *env, void *rip, uint32_t syndrome)
+{
+ const ARMCPRegInfo *ri = rip;
+ int target_el;
+
+ if (arm_feature(env, ARM_FEATURE_XSCALE) && ri->cp < 14
+ && extract32(env->cp15.c15_cpar, ri->cp, 1) == 0) {
+ raise_exception(env, EXCP_UDEF, syndrome, exception_target_el(env));
+ }
+
+ if (!ri->accessfn) {
+ return;
+ }
+
+ switch (ri->accessfn(env, ri)) {
+ case CP_ACCESS_OK:
+ return;
+ case CP_ACCESS_TRAP:
+ target_el = exception_target_el(env);
+ break;
+ case CP_ACCESS_TRAP_EL2:
+ /* Requesting a trap to EL2 when we're in EL3 or S-EL0/1 is
+ * a bug in the access function.
+ */
+ assert(!arm_is_secure(env) && arm_current_el(env) != 3);
+ target_el = 2;
+ break;
+ case CP_ACCESS_TRAP_EL3:
+ target_el = 3;
+ break;
+ case CP_ACCESS_TRAP_UNCATEGORIZED:
+ target_el = exception_target_el(env);
+ syndrome = syn_uncategorized();
+ break;
+ default:
+ g_assert_not_reached();
+ }
+
+ raise_exception(env, EXCP_UDEF, syndrome, target_el);
+}
+
+void HELPER(set_cp_reg)(CPUARMState *env, void *rip, uint32_t value)
+{
+ const ARMCPRegInfo *ri = rip;
+
+ ri->writefn(env, ri, value);
+}
+
+uint32_t HELPER(get_cp_reg)(CPUARMState *env, void *rip)
+{
+ const ARMCPRegInfo *ri = rip;
+
+ return ri->readfn(env, ri);
+}
+
+void HELPER(set_cp_reg64)(CPUARMState *env, void *rip, uint64_t value)
+{
+ const ARMCPRegInfo *ri = rip;
+
+ ri->writefn(env, ri, value);
+}
+
+uint64_t HELPER(get_cp_reg64)(CPUARMState *env, void *rip)
+{
+ const ARMCPRegInfo *ri = rip;
+
+ return ri->readfn(env, ri);
+}
+
+void HELPER(msr_i_pstate)(CPUARMState *env, uint32_t op, uint32_t imm)
+{
+ /* MSR_i to update PSTATE. This is OK from EL0 only if UMA is set.
+ * Note that SPSel is never OK from EL0; we rely on handle_msr_i()
+ * to catch that case at translate time.
+ */
+ if (arm_current_el(env) == 0 && !(env->cp15.sctlr_el[1] & SCTLR_UMA)) {
+ uint32_t syndrome = syn_aa64_sysregtrap(0, extract32(op, 0, 3),
+ extract32(op, 3, 3), 4,
+ imm, 0x1f, 0);
+ raise_exception(env, EXCP_UDEF, syndrome, exception_target_el(env));
+ }
+
+ switch (op) {
+ case 0x05: /* SPSel */
+ update_spsel(env, imm);
+ break;
+ case 0x1e: /* DAIFSet */
+ env->daif |= (imm << 6) & PSTATE_DAIF;
+ break;
+ case 0x1f: /* DAIFClear */
+ env->daif &= ~((imm << 6) & PSTATE_DAIF);
+ break;
+ default:
+ g_assert_not_reached();
+ }
+}
+
+void HELPER(clear_pstate_ss)(CPUARMState *env)
+{
+ env->pstate &= ~PSTATE_SS;
+}
+
+void HELPER(pre_hvc)(CPUARMState *env)
+{
+ ARMCPU *cpu = arm_env_get_cpu(env);
+ int cur_el = arm_current_el(env);
+ /* FIXME: Use actual secure state. */
+ bool secure = false;
+ bool undef;
+
+ if (arm_is_psci_call(cpu, EXCP_HVC)) {
+ /* If PSCI is enabled and this looks like a valid PSCI call then
+ * that overrides the architecturally mandated HVC behaviour.
+ */
+ return;
+ }
+
+ if (!arm_feature(env, ARM_FEATURE_EL2)) {
+ /* If EL2 doesn't exist, HVC always UNDEFs */
+ undef = true;
+ } else if (arm_feature(env, ARM_FEATURE_EL3)) {
+ /* EL3.HCE has priority over EL2.HCD. */
+ undef = !(env->cp15.scr_el3 & SCR_HCE);
+ } else {
+ undef = env->cp15.hcr_el2 & HCR_HCD;
+ }
+
+ /* In ARMv7 and ARMv8/AArch32, HVC is undef in secure state.
+ * For ARMv8/AArch64, HVC is allowed in EL3.
+ * Note that we've already trapped HVC from EL0 at translation
+ * time.
+ */
+ if (secure && (!is_a64(env) || cur_el == 1)) {
+ undef = true;
+ }
+
+ if (undef) {
+ raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+ exception_target_el(env));
+ }
+}
+
+void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome)
+{
+ ARMCPU *cpu = arm_env_get_cpu(env);
+ int cur_el = arm_current_el(env);
+ bool secure = arm_is_secure(env);
+ bool smd = env->cp15.scr_el3 & SCR_SMD;
+ /* On ARMv8 AArch32, SMD only applies to NS state.
+ * On ARMv7 SMD only applies to NS state and only if EL2 is available.
+ * For ARMv7 non EL2, we force SMD to zero so we don't need to re-check
+ * the EL2 condition here.
+ */
+ bool undef = is_a64(env) ? smd : (!secure && smd);
+
+ if (arm_is_psci_call(cpu, EXCP_SMC)) {
+ /* If PSCI is enabled and this looks like a valid PSCI call then
+ * that overrides the architecturally mandated SMC behaviour.
+ */
+ return;
+ }
+
+ if (!arm_feature(env, ARM_FEATURE_EL3)) {
+ /* If we have no EL3 then SMC always UNDEFs */
+ undef = true;
+ } else if (!secure && cur_el == 1 && (env->cp15.hcr_el2 & HCR_TSC)) {
+ /* In NS EL1, HCR controlled routing to EL2 has priority over SMD. */
+ raise_exception(env, EXCP_HYP_TRAP, syndrome, 2);
+ }
+
+ if (undef) {
+ raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+ exception_target_el(env));
+ }
+}
+
+void HELPER(exception_return)(CPUARMState *env)
+{
+ int cur_el = arm_current_el(env);
+ unsigned int spsr_idx = aarch64_banked_spsr_index(cur_el);
+ uint32_t spsr = env->banked_spsr[spsr_idx];
+ int new_el;
+
+ aarch64_save_sp(env, cur_el);
+
+ env->exclusive_addr = -1;
+
+ /* We must squash the PSTATE.SS bit to zero unless both of the
+ * following hold:
+ * 1. debug exceptions are currently disabled
+ * 2. singlestep will be active in the EL we return to
+ * We check 1 here and 2 after we've done the pstate/cpsr write() to
+ * transition to the EL we're going to.
+ */
+ if (arm_generate_debug_exceptions(env)) {
+ spsr &= ~PSTATE_SS;
+ }
+
+ if (spsr & PSTATE_nRW) {
+ /* TODO: We currently assume EL1/2/3 are running in AArch64. */
+ env->aarch64 = 0;
+ new_el = 0;
+ env->uncached_cpsr = 0x10;
+ cpsr_write(env, spsr, ~0);
+ if (!arm_singlestep_active(env)) {
+ env->uncached_cpsr &= ~PSTATE_SS;
+ }
+ aarch64_sync_64_to_32(env);
+
+ env->regs[15] = env->elr_el[1] & ~0x1;
+ } else {
+ new_el = extract32(spsr, 2, 2);
+ if (new_el > cur_el
+ || (new_el == 2 && !arm_feature(env, ARM_FEATURE_EL2))) {
+ /* Disallow return to an EL which is unimplemented or higher
+ * than the current one.
+ */
+ goto illegal_return;
+ }
+ if (extract32(spsr, 1, 1)) {
+ /* Return with reserved M[1] bit set */
+ goto illegal_return;
+ }
+ if (new_el == 0 && (spsr & PSTATE_SP)) {
+ /* Return to EL0 with M[0] bit set */
+ goto illegal_return;
+ }
+ env->aarch64 = 1;
+ pstate_write(env, spsr);
+ if (!arm_singlestep_active(env)) {
+ env->pstate &= ~PSTATE_SS;
+ }
+ aarch64_restore_sp(env, new_el);
+ env->pc = env->elr_el[cur_el];
+ }
+
+ return;
+
+illegal_return:
+ /* Illegal return events of various kinds have architecturally
+ * mandated behaviour:
+ * restore NZCV and DAIF from SPSR_ELx
+ * set PSTATE.IL
+ * restore PC from ELR_ELx
+ * no change to exception level, execution state or stack pointer
+ */
+ env->pstate |= PSTATE_IL;
+ env->pc = env->elr_el[cur_el];
+ spsr &= PSTATE_NZCV | PSTATE_DAIF;
+ spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF);
+ pstate_write(env, spsr);
+ if (!arm_singlestep_active(env)) {
+ env->pstate &= ~PSTATE_SS;
+ }
+}
+
+/* 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 = extract32(cpu->dbgdidr, 24, 4);
+ int ctx_cmps = extract32(cpu->dbgdidr, 20, 4);
+ int bt;
+ uint32_t contextidr;
+
+ /* 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);
+
+ /* 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.
+ */
+ contextidr = extract64(env->cp15.contextidr_el[1], 0, 32);
+
+ switch (bt) {
+ case 3: /* linked context ID match */
+ if (arm_current_el(env) > 1) {
+ /* Context matches never fire in EL2 or (AArch64) EL3 */
+ return false;
+ }
+ return (contextidr == extract64(env->cp15.dbgbvr[lbn], 0, 32));
+ case 5: /* linked address mismatch (reserved in AArch64) */
+ case 9: /* linked VMID match (reserved if no EL2) */
+ case 11: /* linked context ID and VMID match (reserved if no EL2) */
+ default:
+ /* Links to Unlinked context breakpoints must generate no
+ * events; we choose to do the same for reserved values too.
+ */
+ return false;
+ }
+
+ return false;
+}
+
+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 = extract64(cr, 1, 2);
+ hmc = extract64(cr, 13, 1);
+ ssc = extract64(cr, 14, 2);
+
+ 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 = extract64(cr, 20, 1);
+ lbn = extract64(cr, 16, 4);
+
+ 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;
+}
+
+static bool check_breakpoints(ARMCPU *cpu)
+{
+ CPUARMState *env = &cpu->env;
+ 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;
+ }
+
+ for (n = 0; n < ARRAY_SIZE(env->cpu_breakpoint); n++) {
+ if (bp_wp_matches(cpu, n, false)) {
+ return true;
+ }
+ }
+ return false;
+}
+
+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) {
+ cs->watchpoint_hit = NULL;
+ if (check_watchpoints(cpu)) {
+ bool wnr = (wp_hit->flags & BP_WATCHPOINT_HIT_WRITE) != 0;
+ bool same_el = arm_debug_target_el(env) == arm_current_el(env);
+
+ if (extended_addresses_enabled(env)) {
+ env->exception.fsr = (1 << 9) | 0x22;
+ } else {
+ env->exception.fsr = 0x2;
+ }
+ env->exception.vaddress = wp_hit->hitaddr;
+ raise_exception(env, EXCP_DATA_ABORT,
+ syn_watchpoint(same_el, 0, wnr),
+ arm_debug_target_el(env));
+ } else {
+ cpu_resume_from_signal(cs, NULL);
+ }
+ }
+ } else {
+ if (check_breakpoints(cpu)) {
+ bool same_el = (arm_debug_target_el(env) == arm_current_el(env));
+ if (extended_addresses_enabled(env)) {
+ env->exception.fsr = (1 << 9) | 0x22;
+ } else {
+ env->exception.fsr = 0x2;
+ }
+ /* FAR is UNKNOWN, so doesn't need setting */
+ raise_exception(env, EXCP_PREFETCH_ABORT,
+ syn_breakpoint(same_el),
+ arm_debug_target_el(env));
+ }
+ }
+}
+
+/* ??? Flag setting arithmetic is awkward because we need to do comparisons.
+ The only way to do that in TCG is a conditional branch, which clobbers
+ all our temporaries. For now implement these as helper functions. */
+
+/* Similarly for variable shift instructions. */
+
+uint32_t HELPER(shl_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32) {
+ if (shift == 32)
+ env->CF = x & 1;
+ else
+ env->CF = 0;
+ return 0;
+ } else if (shift != 0) {
+ env->CF = (x >> (32 - shift)) & 1;
+ return x << shift;
+ }
+ return x;
+}
+
+uint32_t HELPER(shr_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32) {
+ if (shift == 32)
+ env->CF = (x >> 31) & 1;
+ else
+ env->CF = 0;
+ return 0;
+ } else if (shift != 0) {
+ env->CF = (x >> (shift - 1)) & 1;
+ return x >> shift;
+ }
+ return x;
+}
+
+uint32_t HELPER(sar_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32) {
+ env->CF = (x >> 31) & 1;
+ return (int32_t)x >> 31;
+ } else if (shift != 0) {
+ env->CF = (x >> (shift - 1)) & 1;
+ return (int32_t)x >> shift;
+ }
+ return x;
+}
+
+uint32_t HELPER(ror_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+ int shift1, shift;
+ shift1 = i & 0xff;
+ shift = shift1 & 0x1f;
+ if (shift == 0) {
+ if (shift1 != 0)
+ env->CF = (x >> 31) & 1;
+ return x;
+ } else {
+ env->CF = (x >> (shift - 1)) & 1;
+ return ((uint32_t)x >> shift) | (x << (32 - shift));
+ }
+}