rusticl: allow devices to be enabled by default

Reviewed-by: David Heidelberg <david@ixit.cz>
Acked-by: Eric Engestrom <eric@igalia.com>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31202>

meson_options.txt

@@ -160,6 +160,14 @@ option(
   description : 'build gallium "rusticl" OpenCL frontend.',
 )
 
+option(
+  'gallium-rusticl-enable-drivers',
+  type : 'array',
+  value : ['auto'],
+  description : 'List of gallium drivers for which rusticl will be enabled ' +
+                'by default',
+)
+
 option(
   'gallium-wgl-dll-name',
   type : 'string',

src/gallium/frontends/rusticl/mesa/pipe/device.rs

@@ -55,45 +55,48 @@ fn load_devs() -> impl Iterator<Item = PipeLoaderDevice> {
 fn get_enabled_devs() -> HashMap<String, u32> {
     let mut res = HashMap::new();
 
-    if let Ok(enabled_devs) = env::var("RUSTICL_ENABLE") {
-        let mut last_driver = None;
-        for driver_str in enabled_devs.split(',') {
-            if driver_str.is_empty() {
-                continue;
-            }
+    // we require the type here as this list can be empty depending on the build options
+    let default_devs: &[&str] = &[];
 
-            // if the string parses to a number, just updated the device bitset
-            if let Ok(dev_id) = driver_str.parse::<u8>() {
-                if let Some(last_driver) = last_driver {
-                    *res.get_mut(last_driver).unwrap() |= 1 << dev_id;
-                }
-                continue;
-            } else {
-                let driver_str: Vec<_> = driver_str.split(':').collect();
-                let mut devices = 0;
-
-                if driver_str.len() == 1 {
-                    devices = !0;
-                } else if let Ok(dev_id) = driver_str[1].parse::<u8>() {
-                    devices |= 1 << dev_id;
-                }
-
-                let driver_str = match driver_str[0] {
-                    "llvmpipe" | "lp" => "swrast",
-                    "freedreno" => "msm",
-                    a => a,
-                };
-
-                res.insert(driver_str.to_owned(), devices);
-                last_driver = Some(driver_str);
-            }
+    // I wished we could use different iterators, but that's not really working out.
+    let enabled_devs = env::var("RUSTICL_ENABLE").unwrap_or(default_devs.join(","));
+    let mut last_driver = None;
+    for driver_str in enabled_devs.split(',') {
+        if driver_str.is_empty() {
+            continue;
         }
 
-        if res.contains_key("panfrost") {
-            res.insert("panthor".to_owned(), res["panfrost"]);
+        // if the string parses to a number, just updated the device bitset
+        if let Ok(dev_id) = driver_str.parse::<u8>() {
+            if let Some(last_driver) = last_driver {
+                *res.get_mut(last_driver).unwrap() |= 1 << dev_id;
+            }
+            continue;
+        } else {
+            let driver_str: Vec<_> = driver_str.split(':').collect();
+            let mut devices = 0;
+
+            if driver_str.len() == 1 {
+                devices = !0;
+            } else if let Ok(dev_id) = driver_str[1].parse::<u8>() {
+                devices |= 1 << dev_id;
+            }
+
+            let driver_str = match driver_str[0] {
+                "llvmpipe" | "lp" => "swrast",
+                "freedreno" => "msm",
+                a => a,
+            };
+
+            res.insert(driver_str.to_owned(), devices);
+            last_driver = Some(driver_str);
         }
     }
 
+    if res.contains_key("panfrost") {
+        res.insert("panthor".to_owned(), res["panfrost"]);
+    }
+
     res
 }
 

src/gallium/frontends/rusticl/meson.build

@@ -75,6 +75,13 @@ rusticl_args = [
   '-Aclippy::type_complexity',
 ]
 
+rusticl_drivers_enable = get_option('gallium-rusticl-enable-drivers')
+foreach driver : rusticl_drivers_enable
+  rusticl_args += [
+    '--cfg', 'rusticl_enable_' + driver,
+  ]
+endforeach
+
 if with_platform_x11
   rusticl_args += [
     '--cfg', 'glx',