From 4eb0e42896fde15b3f6e6f34a2d3dce3c025217a Mon Sep 17 00:00:00 2001
From: ga <ga@oldell.fish>
Date: Wed, 16 Mar 2022 19:20:43 +0000
Subject: [PATCH] Fix three problems with gdb support: 1. Do not report a TRAP
 signal on every stop, as it confuses gdb.    Initial symptom was failure to
 step into an ISR. 2. AVR was running after reset command. 3. Excessive
 processor activity (buzzing) while AVR stopped.

---
 simavr/sim/sim_avr.c |  3 +--
 simavr/sim/sim_gdb.c | 14 ++++++++------
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/simavr/sim/sim_avr.c b/simavr/sim/sim_avr.c
index 6e43bf9..8729040 100644
--- a/simavr/sim/sim_avr.c
+++ b/simavr/sim/sim_avr.c
@@ -286,7 +286,7 @@ void
 avr_callback_run_gdb(
 		avr_t * avr)
 {
-	avr_gdb_processor(avr, avr->state == cpu_Stopped);
+	avr_gdb_processor(avr, avr->state == cpu_Stopped ? 50000 : 0);
 
 	if (avr->state == cpu_Stopped)
 		return ;
@@ -331,7 +331,6 @@ avr_callback_run_gdb(
 	// if we were stepping, use this state to inform remote gdb
 	if (step)
 		avr->state = cpu_StepDone;
-
 }
 
 /*
diff --git a/simavr/sim/sim_gdb.c b/simavr/sim/sim_gdb.c
index 702a2cd..d68aea2 100644
--- a/simavr/sim/sim_gdb.c
+++ b/simavr/sim/sim_gdb.c
@@ -210,9 +210,10 @@ gdb_send_quick_status(
 	READ_SREG_INTO(g->avr, sreg);
 
 	sprintf(cmd, "T%02x20:%02x;21:%02x%02x;22:%02x%02x%02x00;",
-		signal ? signal : 5, sreg,
+		signal, sreg,
 		g->avr->data[R_SPL], g->avr->data[R_SPH],
-		g->avr->pc & 0xff, (g->avr->pc>>8)&0xff, (g->avr->pc>>16)&0xff);
+		g->avr->pc & 0xff, (g->avr->pc >> 8) & 0xff,
+		(g->avr->pc >> 16) & 0xff);
 	gdb_send_reply(g, cmd);
 }
 
@@ -314,8 +315,8 @@ handle_monitor(avr_t * avr, avr_gdb_t * g, char * cmd)
 			++ip;
 
 		if (strncmp(ip, "reset", 5) == 0) {
-			avr->state = cpu_StepDone;
 			avr_reset(avr);
+			avr->state = cpu_Stopped;
 			ip += 5;
 		} else if (strncmp(ip, "halt", 4) == 0) {
 			avr->state = cpu_Stopped;
@@ -668,8 +669,8 @@ gdb_handle_command(
 			avr->state = cpu_Step;
 		}	break;
 		case 'r': {	// deprecated, suggested for AVRStudio compatibility
-			avr->state = cpu_StepDone;
 			avr_reset(avr);
+			avr->state = cpu_Stopped;
 		}	break;
 		case 'Z': 	// set clear break/watchpoint
 		case 'z': {
@@ -792,7 +793,8 @@ gdb_network_handler(
 		// control C -- lets send the guy a nice status packet
 		if (*src == 3) {
 			src++;
-			g->avr->state = cpu_StepDone;
+			gdb_send_quick_status(g, 2); // SIGINT
+			g->avr->state = cpu_Stopped;
 			printf("GDB hit control-c\n");
 		}
 		if (*src  == '$') {
@@ -862,7 +864,7 @@ avr_gdb_processor(
 	if (avr->state == cpu_Running &&
 			gdb_watch_find(&g->breakpoints, avr->pc) != -1) {
 		DBG(printf("avr_gdb_processor hit breakpoint at %08x\n", avr->pc);)
-		gdb_send_quick_status(g, 0);
+		gdb_send_quick_status(g, 5);
 		avr->state = cpu_Stopped;
 	} else if (avr->state == cpu_StepDone) {
 		gdb_send_quick_status(g, 0);
-- 
2.39.5