[Qemu-devel] [PATCH v2 19/23] target/arm: Move watchpoints APIs to helper.c

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

From: Samuel Ortiz <sameo@linux.intel.com>

Here again, those APIs are not TCG dependent and can move to the always
built helper.c.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Robert Bradford <robert.bradford@intel.com>
[PMD: Rebased]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 target/arm/helper.c    | 213 +++++++++++++++++++++++++++++++++++++++++
 target/arm/internals.h |   6 ++
 target/arm/op_helper.c | 213 -----------------------------------------
 3 files changed, 219 insertions(+), 213 deletions(-)

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 8c32b2bc0d..8b7ce0561b 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -11508,3 +11508,216 @@ void arm_cpu_dump_state(CPUState *cs, FILE *f, int flags)
         qemu_fprintf(f, "FPSCR: %08x\n", vfp_get_fpscr(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 = 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;
+}
+
+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;
+}
+
+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);
+}
+
+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;
+}
diff --git a/target/arm/internals.h b/target/arm/internals.h
index 56281d8ece..fbbc701bb0 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -1042,6 +1042,12 @@ bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address,
                        int *prot, bool *is_subpage,
                        ARMMMUFaultInfo *fi, uint32_t *mregion);
 
+/*
+ * Returns true when the current CPU execution context matches
+ * the watchpoint or the breakpoint pointed at by n.
+ */
+bool bp_wp_matches(ARMCPU *cpu, int n, bool is_wp);
+
 #ifdef TARGET_AARCH64
 void aarch64_cpu_dump_state(CPUState *cs, FILE *f, int flags);
 #else
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index 63bce32810..68740e1b30 100644
--- a/target/arm/op_helper.c
+++ b/target/arm/op_helper.c
@@ -1018,185 +1018,6 @@ void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome)
     }
 }
 
-/* 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;
@@ -1227,40 +1048,6 @@ void HELPER(check_breakpoints)(CPUARMState *env)
     }
 }
 
-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);
-}
-
-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;
-}
-
 void arm_debug_excp_handler(CPUState *cs)
 {
     /* Called by core code when a watchpoint or breakpoint fires;
-- 
2.20.1