gem5: use m5term instead of telnet

Author: cirosantilli

README.adoc

@@ -6463,6 +6463,18 @@ So let's explain them one by one here as we understand them:
 * `drm: Add component-aware simple encoder` allows you to see images through VNC: <<graphic-mode-gem5>>
 * `gem5: Add support for gem5's extended GIC mode` adds support for more than 8 cores: https://stackoverflow.com/questions/50248067/how-to-run-a-gem5-arm-aarch64-full-system-simulation-with-fs-py-with-more-than-8/50248068#5024806
 
+=== m5term
+
+We use the `m5term` in-tree executable to connect to the terminal instead of a direct `telnet`.
+
+If you use `telnet` directly, it mostly works, but certain interactive features don't, e.g.:
+
+* up and down arrows for history havigation
+* tab to complete paths
+* `Ctrl-C` to kill processes
+
+TODO understand in detail what `m5term` does differently than `telnet`.
+
 === gem5 stats
 
 Lets try to understand some stats better.

common

@@ -78,6 +78,7 @@ set_common_vars() {
     common_gem5_src_dir="${common_gem5_non_default_src_root_dir}/${gem5_variant}"
   fi
   common_gem5_out_dir="${common_dir}/gem5/${gem5_variant}"
+  common_gem5_m5term="${common_gem5_out_dir}/m5term"
   common_gem5_build_dir="${common_gem5_out_dir}/build"
   common_gem5_system_dir="${common_gem5_out_dir}/system"
   common_gem5_run_dir="${out_arch_dir}/gem5/${gem5_variant}/${common_run_id}"

gem5-shell

@@ -1,7 +1,10 @@
 #!/usr/bin/env bash
 . common
-while getopts n: OPT; do
+while getopts M:n: OPT; do
   case "$OPT" in
+    M)
+      common_gem5_variant="$OPTARG"
+      ;;
     n)
       common_run_id="$OPTARG"
       ;;
@@ -11,5 +14,5 @@ while getopts n: OPT; do
   esac
 done
 shift "$(($OPTIND - 1))"
-set_common_vars -n "$common_run_id" "$arch" true
-telnet localhost "$common_gem5_telnet_port"
+set_common_vars -M "$common_gem5_variant" -n "$common_run_id" "$arch" true
+"${common_gem5_m5term}" localhost "$common_gem5_telnet_port"

gem5/build

@@ -50,5 +50,5 @@ elif [ "$arch" = arm ] || [ "$arch" = aarch64 ]; then
   make -C ./system/arm/aarch64_bootloader/ $cross_compile
   cp ./system/arm/aarch64_bootloader/boot_emm.arm64 "$binaries_dir"
 fi
-# TODO vs telnet?
 make -C util/term
+cp util/term/m5term "${outdir}"