hvf: add breakpoint handlers

Required for guest debugging. The code has been structured like the KVM
counterpart.

Signed-off-by: Francesco Cagnin <fcagnin@quarkslab.com>
Message-id: 20230601153107.81955-4-fcagnin@quarkslab.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 63 insertions, 0 deletions

diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c
index e221e37055..bb83627727 100644
--- a/target/arm/hvf/hvf.c
+++ b/target/arm/hvf/hvf.c
@@ -31,6 +31,8 @@
 #include "trace/trace-target_arm_hvf.h"
 #include "migration/vmstate.h"
 
+#include "exec/gdbstub.h"
+
 #define HVF_SYSREG(crn, crm, op0, op1, op2) \
         ENCODE_AA64_CP_REG(CP_REG_ARM64_SYSREG_CP, crn, crm, op0, op1, op2)
 #define PL1_WRITE_MASK 0x4
@@ -1711,3 +1713,64 @@ int hvf_arch_init(void)
     qemu_add_vm_change_state_handler(hvf_vm_state_change, &vtimer);
     return 0;
 }
+
+static const uint32_t brk_insn = 0xd4200000;
+
+int hvf_arch_insert_sw_breakpoint(CPUState *cpu, struct hvf_sw_breakpoint *bp)
+{
+    if (cpu_memory_rw_debug(cpu, bp->pc, (uint8_t *)&bp->saved_insn, 4, 0) ||
+        cpu_memory_rw_debug(cpu, bp->pc, (uint8_t *)&brk_insn, 4, 1)) {
+        return -EINVAL;
+    }
+    return 0;
+}
+
+int hvf_arch_remove_sw_breakpoint(CPUState *cpu, struct hvf_sw_breakpoint *bp)
+{
+    static uint32_t brk;
+
+    if (cpu_memory_rw_debug(cpu, bp->pc, (uint8_t *)&brk, 4, 0) ||
+        brk != brk_insn ||
+        cpu_memory_rw_debug(cpu, bp->pc, (uint8_t *)&bp->saved_insn, 4, 1)) {
+        return -EINVAL;
+    }
+    return 0;
+}
+
+int hvf_arch_insert_hw_breakpoint(target_ulong addr, target_ulong len, int type)
+{
+    switch (type) {
+    case GDB_BREAKPOINT_HW:
+        return insert_hw_breakpoint(addr);
+    case GDB_WATCHPOINT_READ:
+    case GDB_WATCHPOINT_WRITE:
+    case GDB_WATCHPOINT_ACCESS:
+        return insert_hw_watchpoint(addr, len, type);
+    default:
+        return -ENOSYS;
+    }
+}
+
+int hvf_arch_remove_hw_breakpoint(target_ulong addr, target_ulong len, int type)
+{
+    switch (type) {
+    case GDB_BREAKPOINT_HW:
+        return delete_hw_breakpoint(addr);
+    case GDB_WATCHPOINT_READ:
+    case GDB_WATCHPOINT_WRITE:
+    case GDB_WATCHPOINT_ACCESS:
+        return delete_hw_watchpoint(addr, len, type);
+    default:
+        return -ENOSYS;
+    }
+}
+
+void hvf_arch_remove_all_hw_breakpoints(void)
+{
+    if (cur_hw_wps > 0) {
+        g_array_remove_range(hw_watchpoints, 0, cur_hw_wps);
+    }
+    if (cur_hw_bps > 0) {
+        g_array_remove_range(hw_breakpoints, 0, cur_hw_bps);
+    }
+}