meson: Add a configuration option to build IPAs

There can be multiple IPAs per pipeline-handler or platform.
They can live in-tree or externally linked. It is up to the vendor
whether to use in-tree IPA for a platform or provide it externally.
In the case of IPAs being external, building in-tree IPAs might be
futile hence, provide a clear and explicit mechanism to choose whether
to build the in-tree IPA for the platform or not.

By default, all in-tree IPAs are built when a matching Pipeline handler
is also enabled.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

meson.build

@@ -167,6 +167,7 @@ py_mod.find_installation('python3', modules: py_modules)
 ## Summarise Configurations
 summary({
             'Enabled pipelines': pipelines,
+            'Enabled IPA modules': ipa_modules,
             'Android support': android_enabled,
             'GStreamer support': gst_enabled,
             'V4L2 emulation support': v4l2_enabled,

meson_options.txt

@@ -25,6 +25,11 @@ option('gstreamer',
         value : 'auto',
         description : 'Compile libcamera GStreamer plugin')
 
+option('ipas',
+        type : 'array',
+        choices : ['ipu3', 'raspberrypi', 'rkisp1', 'vimc'],
+        description : 'Select which IPA modules to build')
+
 option('lc-compliance',
         type : 'feature',
         value : 'auto',

src/ipa/meson.build

@@ -19,14 +19,15 @@ subdir('libipa')
 
 ipa_sign = files('ipa-sign.sh')
 
-ipas = ['ipu3', 'raspberrypi', 'rkisp1', 'vimc']
 ipa_names = []
 
+ipa_modules = get_option('ipas')
+
 # The ipa-sign-install.sh script which uses the ipa_names variable will itself
 # prepend MESON_INSTALL_DESTDIR_PREFIX to each ipa module name, therefore we
 # must not include the prefix string here.
 foreach pipeline : pipelines
-    if ipas.contains(pipeline)
+    if ipa_modules.contains(pipeline)
         subdir(pipeline)
         ipa_names += ipa_install_dir / ipa_name + '.so'
     endif