3 files changed, 98 insertions, 0 deletions

diff --git a/drminfo.c b/drminfo.c
index 97ab8da..2020ddb 100644
--- a/drminfo.c
+++ b/drminfo.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
@@ -8,6 +9,7 @@
 #include <getopt.h>
 
 #include <sys/ioctl.h>
+#include <drm/drm_fourcc.h>
 
 #include <xf86drm.h>
 #include <xf86drmMode.h>
@@ -99,6 +101,51 @@ static void drm_info(int devnr)
         drmModeFreeConnector(conn);
         fprintf(stdout, "\n");
     }
+
+    fprintf(stdout, "legacy formats\n");
+    drm_probe_format(fd, 32, 24, 0, true);
+    drm_probe_format(fd, 32, 30, 0, true);
+    drm_probe_format(fd, 24, 24, 0, true);
+    drm_probe_format(fd, 16, 16, 0, true);
+    drm_probe_format(fd, 16, 15, 0, true);
+    fprintf(stdout, "\n");
+
+    fprintf(stdout, "fourcc formats\n");
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_XRGB8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_XBGR8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_RGBX8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_BGRX8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_ARGB8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_ABGR8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_RGBA8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_BGRA8888,    true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_XRGB2101010, true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_XBGR2101010, true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_RGBX1010102, true);
+    drm_probe_format(fd, 32, 0, DRM_FORMAT_BGRX1010102, true);
+
+    drm_probe_format(fd, 24, 0, DRM_FORMAT_RGB888,      true);
+    drm_probe_format(fd, 24, 0, DRM_FORMAT_BGR888,      true);
+
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_XRGB4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_XBGR4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_RGBX4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_BGRX4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_ARGB4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_ABGR4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_RGBA4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_BGRA4444,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_XRGB1555,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_XBGR1555,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_RGBX5551,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_BGRX5551,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_ARGB1555,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_ABGR1555,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_RGBA5551,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_BGRA5551,    true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_RGB565,      true);
+    drm_probe_format(fd, 16, 0, DRM_FORMAT_BGR565,      true);
+    fprintf(stdout, "\n");
 }
 
 /* ------------------------------------------------------------------ */
diff --git a/drmtools.c b/drmtools.c
index 8ff054b..042b8d6 100644
--- a/drmtools.c
+++ b/drmtools.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
@@ -92,3 +93,52 @@ void drm_conn_name(drmModeConnector *conn, char *dest, int dlen)
 
 /* ------------------------------------------------------------------ */
 
+bool drm_probe_format(int fd, uint32_t bpp, uint32_t depth, uint32_t fourcc, bool print)
+{
+    struct drm_mode_create_dumb cd;
+    struct drm_mode_destroy_dumb dd;
+    uint32_t zero = 0;
+    uint32_t fb_id = 0;
+    bool result = false;
+    int rc;
+
+    /* create dumb buffer */
+    memset(&cd, 0, sizeof(cd));
+    cd.width = 64;
+    cd.height = 64;
+    cd.bpp = bpp;
+    rc = drmIoctl(fd, DRM_IOCTL_MODE_CREATE_DUMB, &cd);
+    if (rc < 0)
+        goto done;
+
+    /* create framebuffer */
+    if (fourcc) {
+        rc = drmModeAddFB2(fd, cd.width, cd.height, fourcc,
+                           &cd.handle, &cd.pitch, &zero,
+                           &fb_id, 0);
+        if (rc == 0 && print)
+            printf("    bpp %d, fourcc %c%c%c%c\n", cd.bpp,
+                   (fourcc >>  0) & 0xff,
+                   (fourcc >>  8) & 0xff,
+                   (fourcc >> 16) & 0xff,
+                   (fourcc >> 24) & 0xff);
+    } else if (depth) {
+        rc = drmModeAddFB(fd, cd.width, cd.height, depth, cd.bpp,
+                          cd.pitch, cd.handle, &fb_id);
+        if (rc == 0 && print)
+            printf("    bpp %d, depth %d\n", cd.bpp, depth);
+    } else {
+        rc = -1;
+    }
+
+    if (rc == 0) {
+        /* worked, yay! */
+        result = true;
+        drmModeRmFB(fd, fb_id);
+    }
+    dd.handle = cd.handle;
+    drmIoctl(fd, DRM_IOCTL_MODE_DESTROY_DUMB, &dd);
+
+done:
+    return result;
+}
diff --git a/drmtools.h b/drmtools.h
index ed43544..9560261 100644
--- a/drmtools.h
+++ b/drmtools.h
@@ -2,3 +2,4 @@ const char *drm_connector_type_name(int nr);
 const char *drm_connector_mode_name(int nr);
 const char *drm_encoder_type_name(int nr);
 void drm_conn_name(drmModeConnector *conn, char *dest, int dlen);
+bool drm_probe_format(int fd, uint32_t bpp, uint32_t depth, uint32_t fourcc, bool print);