NuttX debug helper improvements

- use NuttX gdb script for nxthreads and thread backtrace
 - update jlink_gdb_backtrace and jlink_debug_gdb helper targets to use
NuttX gdb script
 - Debug/PX4 fix "perf" divide by zero
 - Debug/PX4 add "dmesg"

platforms/nuttx/Debug/PX4

@@ -11,6 +11,9 @@ end
 document px4
 . Various macros for working with the PX4 firmware.
 .
+.    dmesg
+.        Prints the dmesg output (if available).
+.
 .    perf
 .        Prints the state of all performance counters.
 .
@@ -18,6 +21,22 @@ document px4
 end
 
 
+define dmesg
+	if g_console_buffer
+		printf "PX4 dmesg:\n"
+		# TODO: respect head and tail
+		printf "%s\n", g_console_buffer._buffer
+	else
+		printf "PX4 dmesg unavailable\n"
+	end
+end
+
+document dmesg
+.    dmesg
+.        Prints dmesg (if available).
+end
+
+
 define _perf_print
 	set $hdr = (struct perf_ctr_header *)$arg0
 	#printf "%p\n", $hdr
@@ -35,7 +54,11 @@ define _perf_print
 	# PC_INTERVAL
 	if $hdr->type == 2
 		set $interval = (struct perf_ctr_interval *)$hdr
-		printf "%llu events, %llu avg, min %lluus max %lluus\n", $interval->event_count, ($interval->time_last - $interval->time_first) / $interval->event_count, $interval->time_least, $interval->time_most
+		if $interval->event_count == 0
+			printf "%llu events, %llu avg, min %lluus max %lluus\n", $interval->event_count, 0, $interval->time_least, $interval->time_most
+		else
+			printf "%llu events, %llu avg, min %lluus max %lluus\n", $interval->event_count, ($interval->time_last - $interval->time_first) / $interval->event_count, $interval->time_least, $interval->time_most
+		end
 	end
 end
 

platforms/nuttx/Debug/jlink_debug_gdb.sh.in

@@ -1,9 +1,23 @@
 #! /bin/sh
 
+if command -v gdb-multiarch &> /dev/null
+then
+	GDB_CMD=$(command -v gdb-multiarch)
+
+elif command -v arm-none-eabi-gdb &> /dev/null
+then
+	GDB_CMD=$(command -v arm-none-eabi-gdb)
+
+else
+	echo "gdb arm-none-eabi or multi-arch not found"
+	exit 1
+fi
+
 @JLinkGDBServerExe_PATH@ -device @DEBUG_DEVICE@ -select usb -endian little -if SWD -speed auto -ir -LocalhostOnly 1 -strict -vd -singlerun &
 
-cd @PX4_BINARY_DIR@ && @CMAKE_GDB@ -silent -nh \
+cd @PX4_BINARY_DIR@ && ${GDB_CMD} -silent -nh \
 	-iex "set auto-load safe-path @PX4_BINARY_DIR@" \
+	-ix=@PX4_SOURCE_DIR@/platforms/nuttx/NuttX/nuttx/tools/nuttx-gdbinit \
 	-ex "target remote localhost:2331" \
 	-ex "monitor reset 0" \
 	-ex "load" \

platforms/nuttx/Debug/jlink_gdb_backtrace.sh

@@ -19,23 +19,31 @@ gdb_cmd_file=$(mktemp)
 
 cat >"${gdb_cmd_file}" <<EOL
 
-source ${WORKSPACE}/platforms/nuttx/Debug/NuttX
 source ${WORKSPACE}/platforms/nuttx/Debug/ARMv7M
+source ${WORKSPACE}/platforms/nuttx/Debug/NuttX
+source ${WORKSPACE}/platforms/nuttx/Debug/PX4
+
+set mem inaccessible-by-default off
+set print pretty
+set pagination off
 
 target remote localhost:2331
 
 monitor regs
 
+dmesg
+
+perf
+
 showtasks
+backtrace
 
 vecstate
 
-info threads
+info_nxthreads
 
-backtrace
-
-bt full
+nxthread_all_bt
 
 EOL
 
-${GDB_CMD} -silent --nh --nx --nw -batch -x ${gdb_cmd_file} ${1}
+${GDB_CMD} -silent --nh --nx --nw -batch -ix=${WORKSPACE}/platforms/nuttx/NuttX/nuttx/tools/nuttx-gdbinit -x ${gdb_cmd_file} ${1}

platforms/nuttx/Debug/jlink_gdb_backtrace_simple.sh

@@ -0,0 +1,49 @@
+#! /bin/sh
+
+if command -v gdb-multiarch &> /dev/null
+then
+	GDB_CMD=$(command -v gdb-multiarch)
+
+elif command -v arm-none-eabi-gdb &> /dev/null
+then
+	GDB_CMD=$(command -v arm-none-eabi-gdb)
+
+else
+	echo "gdb arm-none-eabi or multi-arch not found"
+	exit 1
+fi
+
+file ${1}
+
+gdb_cmd_file=$(mktemp)
+
+cat >"${gdb_cmd_file}" <<EOL
+
+source ${WORKSPACE}/platforms/nuttx/Debug/ARMv7M
+source ${WORKSPACE}/platforms/nuttx/Debug/NuttX
+source ${WORKSPACE}/platforms/nuttx/Debug/PX4
+
+set mem inaccessible-by-default off
+set print pretty
+set pagination off
+
+target remote localhost:2331
+
+monitor regs
+
+dmesg
+
+perf
+
+showtasks
+backtrace
+
+vecstate
+
+info threads
+
+bt full
+
+EOL
+
+${GDB_CMD} -silent --nh --nx --nw -batch -x ${gdb_cmd_file} ${1}