From 6b554b3b0e34fe0a1d37a1584baf3c3e32a76b57 Mon Sep 17 00:00:00 2001 From: David Ung Date: Mon, 20 Apr 2015 13:14:43 -0700 Subject: [PATCH] aarch64: Correct target state for hardware step When using hardware step for doing stepping, the existing DSCR records the event as external debug request. This will generate a SIGINT event to GDB and causes it to stop the stepping process. For aarch64, read DESR to check if the event is a hardware step and set state to DBG_REASON_SINGLESTEP. With this patch, GDB can now do source level stepping. Change-Id: I1d06f819578c74b3ac17376c67f882adddea1f52 Signed-off-by: David Ung Signed-off-by: Matthias Welwarsky --- src/target/aarch64.c | 13 +++++++++++-- src/target/armv8.h | 1 + 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/src/target/aarch64.c b/src/target/aarch64.c index a2b020bfd1..78d19731e7 100644 --- a/src/target/aarch64.c +++ b/src/target/aarch64.c @@ -1063,6 +1063,7 @@ static int aarch64_debug_entry(struct target *target) int retval = ERROR_OK; struct aarch64_common *aarch64 = target_to_aarch64(target); struct armv8_common *armv8 = target_to_armv8(target); + uint32_t tmp; LOG_DEBUG("dscr = 0x%08" PRIx32, aarch64->cpudbg_dscr); @@ -1086,6 +1087,10 @@ static int aarch64_debug_entry(struct target *target) /* Examine debug reason */ arm_dpm_report_dscr(&armv8->dpm, aarch64->cpudbg_dscr); + mem_ap_read_atomic_u32(armv8->debug_ap, + armv8->debug_base + CPUDBG_DESR, &tmp); + if ((tmp & 0x7) == 0x4) + target->debug_reason = DBG_REASON_SINGLESTEP; /* save address of instruction that triggered the watchpoint? */ if (target->debug_reason == DBG_REASON_WATCHPOINT) { @@ -1164,12 +1169,16 @@ static int aarch64_step(struct target *target, int current, target_addr_t addres if (retval != ERROR_OK) return retval; + target->debug_reason = DBG_REASON_SINGLESTEP; retval = aarch64_resume(target, 1, address, 0, 0); if (retval != ERROR_OK) return retval; long long then = timeval_ms(); while (target->state != TARGET_HALTED) { + mem_ap_read_atomic_u32(armv8->debug_ap, + armv8->debug_base + CPUDBG_DESR, &tmp); + LOG_DEBUG("DESR = %#x", tmp); retval = aarch64_poll(target); if (retval != ERROR_OK) return retval; @@ -1179,13 +1188,13 @@ static int aarch64_step(struct target *target, int current, target_addr_t addres } } - target->debug_reason = DBG_REASON_BREAKPOINT; retval = mem_ap_write_atomic_u32(armv8->debug_ap, armv8->debug_base + CPUDBG_DECR, (tmp&(~0x4))); if (retval != ERROR_OK) return retval; - if (target->state != TARGET_HALTED) + target_call_event_callbacks(target, TARGET_EVENT_HALTED); + if (target->state == TARGET_HALTED) LOG_DEBUG("target stepped"); return ERROR_OK; diff --git a/src/target/armv8.h b/src/target/armv8.h index 58e4228c56..47e36680ed 100644 --- a/src/target/armv8.h +++ b/src/target/armv8.h @@ -161,6 +161,7 @@ target_to_armv8(struct target *target) /* register offsets from armv8.debug_base */ #define CPUDBG_WFAR 0x018 +#define CPUDBG_DESR 0x020 #define CPUDBG_DECR 0x024 /* PCSR at 0x084 -or- 0x0a0 -or- both ... based on flags in DIDR */ #define CPUDBG_DSCR 0x088 -- 2.30.2