Restored the default auto zoom out of gtkwave, it can now be disable by configuring apio.ini.

Author: zapta

apio/scons/plugin_util.py

@@ -461,7 +461,11 @@ def create_default_gtkw_file(
 
         # -- The actual wave viewer command.
         gtkwave_cmd = ["gtkwave"]
-        gtkwave_cmd.extend(["--rcvar=splash_disable on"])
+        # -- NOTE: Users can override these rcvars by adding the desired
+        # -- rcvar options in apio.ini gtkwave-extra-options which will win
+        # -- since they will appear later in the command line.
+        gtkwave_cmd.append("--rcvar=splash_disable on")
+        gtkwave_cmd.append("--rcvar=do_initial_zoom_fit 1")
         if gtkwave_extra_options:
             gtkwave_cmd.extend(gtkwave_extra_options)
         gtkwave_cmd.extend([vcd_path, gtkw_path])

docs/cmd-apio-sim.md

@@ -18,6 +18,17 @@ signals, modify them in GTKWave and save your configuration using the
 `File > Write Save File` menu command. The `apio sim` command will never
 overwrite a `.gtkw` files that were saved in this way.
 
+The command line that used to invoke the signal viewer `gtkwave` can be 
+customized using the `apio.ini` option `gtkwave-extra-options`. 
+For example, the option below disables the var `do_initial_zoom_fit` to prevent
+gtkwave from forcing a fully-out zoom upon start.
+
+```
+[env:default]
+gtkwave-extra-options =
+    --rcvar=do_initial_zoom_fit 0
+```
+
 The `apio sim` command defines the macro `APIO_SIM=1`, which allows failed
 assertions to skip the `$fatal` call. This lets the simulation continue and
 display faulty signals in the GTKWave viewer.

docs/project-file.md

@@ -173,13 +173,13 @@ raw -- verible-verilog-format --helpfull`
 
 The optional `gtkwave-extra-options` string list option allows adding options to the
 gtkwave command that that is invoked by the `apio sim`.
-In the example below, it enable the flag `do_initial_zoom_fit` to force
-gtkwave to always start with a fully zoomed out view of the signals.
+For example, the option below disables the var `do_initial_zoom_fit` to prevent
+gtkwave from forcing a fully-out zoom upon start.
 
 ```
 [env:default]
 gtkwave-extra-options =
-    --rcvar=do_initial_zoom_fit 1
+    --rcvar=do_initial_zoom_fit 0
 ```
 
 ### nextpnr-extra-options