aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--target-arm/cpu.c2
-rw-r--r--target-arm/cpu.h2
-rw-r--r--target-arm/helper.c135
-rw-r--r--target-arm/internals.h10
-rw-r--r--target-arm/machine.c3
5 files changed, 149 insertions, 3 deletions
diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index bdd23b42b6..6c40ecdeed 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -184,6 +184,8 @@ static void arm_cpu_reset(CPUState *s)
kvm_arm_reset_vcpu(cpu);
}
#endif
+
+ hw_watchpoint_update_all(cpu);
}
#ifndef CONFIG_USER_ONLY
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index 51bedc8262..d1e1ccb605 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -323,6 +323,8 @@ typedef struct CPUARMState {
int eabi;
#endif
+ struct CPUWatchpoint *cpu_watchpoint[16];
+
CPU_COMMON
/* These fields after the common ones so they are preserved on reset. */
diff --git a/target-arm/helper.c b/target-arm/helper.c
index 2b95f33872..103dfb8a9d 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -2279,6 +2279,131 @@ static const ARMCPRegInfo debug_lpae_cp_reginfo[] = {
REGINFO_SENTINEL
};
+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 (!extract64(wcr, 0, 1)) {
+ /* E bit clear : watchpoint disabled */
+ return;
+ }
+
+ switch (extract64(wcr, 3, 2)) {
+ 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 = extract64(wcr, 24, 4);
+ 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 = extract64(wcr, 5, 8);
+ int basstart;
+
+ if (bas == 0) {
+ /* This must act as if the watchpoint is disabled */
+ return;
+ }
+
+ 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;
+ }
+ /* 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 = arm_env_get_cpu(env);
+ int i = ri->crm;
+
+ /* Bits [63:49] are hardwired to the value of bit [48]; that is, the
+ * register reads and behaves as if values written are sign extended.
+ * Bits [1:0] are RES0.
+ */
+ value = sextract64(value, 0, 49) & ~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 = arm_env_get_cpu(env);
+ int i = ri->crm;
+
+ raw_write(env, ri, value);
+ hw_watchpoint_update(cpu, i);
+}
+
static void define_debug_regs(ARMCPU *cpu)
{
/* Define v7 and v8 architectural debug registers.
@@ -2330,12 +2455,16 @@ static void define_debug_regs(ARMCPU *cpu)
{ .name = "DBGWVR", .state = ARM_CP_STATE_BOTH,
.cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = i, .opc2 = 6,
.access = PL1_RW,
- .fieldoffset = offsetof(CPUARMState, cp15.dbgwvr[i]) },
+ .fieldoffset = offsetof(CPUARMState, cp15.dbgwvr[i]),
+ .writefn = dbgwvr_write, .raw_writefn = raw_write
+ },
{ .name = "DBGWCR", .state = ARM_CP_STATE_BOTH,
.cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = i, .opc2 = 7,
.access = PL1_RW,
- .fieldoffset = offsetof(CPUARMState, cp15.dbgwcr[i]) },
- REGINFO_SENTINEL
+ .fieldoffset = offsetof(CPUARMState, cp15.dbgwcr[i]),
+ .writefn = dbgwcr_write, .raw_writefn = raw_write
+ },
+ REGINFO_SENTINEL
};
define_arm_cp_regs(cpu, dbgregs);
}
diff --git a/target-arm/internals.h b/target-arm/internals.h
index 53c2e3cf3e..22f382c0c6 100644
--- a/target-arm/internals.h
+++ b/target-arm/internals.h
@@ -296,4 +296,14 @@ static inline uint32_t syn_swstep(int same_el, int isv, int ex)
| (isv << 24) | (ex << 6) | 0x22;
}
+/* Update a QEMU watchpoint based on the information the guest has set in the
+ * DBGWCR<n>_EL1 and DBGWVR<n>_EL1 registers.
+ */
+void hw_watchpoint_update(ARMCPU *cpu, int n);
+/* Update the QEMU watchpoints for every guest watchpoint. This does a
+ * complete delete-and-reinstate of the QEMU watchpoint list and so is
+ * suitable for use after migration or on reset.
+ */
+void hw_watchpoint_update_all(ARMCPU *cpu);
+
#endif
diff --git a/target-arm/machine.c b/target-arm/machine.c
index 3bcc7cc833..8dfe87cb6b 100644
--- a/target-arm/machine.c
+++ b/target-arm/machine.c
@@ -2,6 +2,7 @@
#include "hw/boards.h"
#include "sysemu/kvm.h"
#include "kvm_arm.h"
+#include "internals.h"
static bool vfp_needed(void *opaque)
{
@@ -213,6 +214,8 @@ static int cpu_post_load(void *opaque, int version_id)
}
}
+ hw_watchpoint_update_all(cpu);
+
return 0;
}