Start adding PX4 firmware helper macros

Debug/PX4

@@ -0,0 +1,54 @@
+#
+# Various PX4-specific macros
+#
+source Debug/NuttX
+
+echo Loading PX4 GDB macros. Use 'help px4' for more information.\n
+
+define px4
+ echo Use 'help px4' for more information.\n
+end
+
+document px4
+. Various macros for working with the PX4 firmware.
+.
+. perf
+. Prints the state of all performance counters.
+.
+. Use 'help <macro>' for more specific help.
+end
+
+
+define _perf_print
+ set $hdr = (struct perf_ctr_header *)$arg0
+ printf "%p\n", $hdr
+ printf "%s: ", $hdr->name
+ # PC_COUNT
+ if $hdr->type == 0
+ set $count = (struct perf_ctr_count *)$hdr
+ printf "%llu events,\n", $count->event_count;
+ end
+ # PC_ELPASED
+ if $hdr->type == 1
+ set $elapsed = (struct perf_ctr_elapsed *)$hdr
+ printf "%llu events, %lluus elapsed, min %lluus, max %lluus\n", $elapsed->event_count, $elapsed->time_total, $elapsed->time_least, $elapsed->time_most
+ end
+ # 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
+ end
+end
+
+define perf
+ set $ctr = (sq_entry_t *)(perf_counters.head)
+ while $ctr != 0
+ _perf_print $ctr
+ set $ctr = $ctr->flink
+ end
+end
+
+document perf
+. perf
+. Prints performance counters.
+end