loader: allow DRI_PRIME=vendor_id:device_id syntax

This syntax allows to select a specific GPU without depending on
the pci bus information.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17298>

1 files changed, 17 insertions, 3 deletions

diff --git a/src/loader/loader.c b/src/loader/loader.c
index 7cef1d49f60..4ebd5429ec0 100644
--- a/src/loader/loader.c
+++ b/src/loader/loader.c
@@ -328,6 +328,8 @@ int loader_get_user_preferred_fd(int default_fd, bool *different_device)
    char *default_tag, *prime = NULL;
    drmDevicePtr devices[MAX_DRM_DEVICES];
    int i, num_devices, fd = -1;
+   bool prime_is_vid_did;
+   uint16_t vendor_id, device_id;
 
    if (dri_prime)
       prime = strdup(dri_prime);
@@ -339,6 +341,8 @@ int loader_get_user_preferred_fd(int default_fd, bool *different_device)
    if (prime == NULL) {
       *different_device = false;
       return default_fd;
+   } else {
+      prime_is_vid_did = sscanf(prime, "%hx:%hx", &vendor_id, &device_id) == 2;
    }
 
    default_tag = drm_get_id_path_tag_for_fd(default_fd);
@@ -353,17 +357,27 @@ int loader_get_user_preferred_fd(int default_fd, bool *different_device)
       if (!(devices[i]->available_nodes & 1 << DRM_NODE_RENDER))
          continue;
 
-      /* two formats of DRI_PRIME are supported:
+      /* three formats of DRI_PRIME are supported:
        * "1": choose any other card than the card used by default.
        * id_path_tag: (for example "pci-0000_02_00_0") choose the card
        * with this id_path_tag.
+       * vendor_id:device_id
        */
       if (!strcmp(prime,"1")) {
          if (drm_device_matches_tag(devices[i], default_tag))
             continue;
       } else {
-         if (!drm_device_matches_tag(devices[i], prime))
-            continue;
+         if (prime_is_vid_did && devices[i]->bustype == DRM_BUS_PCI &&
+             devices[i]->deviceinfo.pci->vendor_id == vendor_id &&
+             devices[i]->deviceinfo.pci->device_id == device_id) {
+            /* Update prime for the "different_device"
+             * determination below. */
+            free(prime);
+            prime = drm_construct_id_path_tag(devices[i]);
+         } else {
+            if (!drm_device_matches_tag(devices[i], prime))
+               continue;
+         }
       }
 
       fd = loader_open_device(devices[i]->nodes[DRM_NODE_RENDER]);