[PATCH 7/9] drm/fb-helper: Fix single-probe color-format selection
Thomas Zimmermann
tzimmermann at suse.de
Tue Dec 13 20:12:31 UTC 2022
Fix the color-format selection of the single-probe helper. Go
through all user-specified values and test each for compatibility
with the driver. If none is supported, use the driver-provided
default. This guarantees that the console is always available in
any color format at least.
Until now, the format selection of the single-probe helper tried
to either use a user-specified format or a 32-bit default format.
If the user-specified format was not supported by the driver, the
selection failed and the display remained blank.
Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
drivers/gpu/drm/drm_fb_helper.c | 172 +++++++++++++++++---------------
1 file changed, 94 insertions(+), 78 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index af1495394d38..1369ca4ae39b 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1726,6 +1726,70 @@ int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
}
EXPORT_SYMBOL(drm_fb_helper_pan_display);
+static uint32_t drm_fb_helper_find_format(struct drm_fb_helper *fb_helper, const uint32_t *formats,
+ size_t format_count, uint32_t bpp, uint32_t depth)
+{
+ struct drm_device *dev = fb_helper->dev;
+ uint32_t format;
+ size_t i;
+
+ /*
+ * Do not consider YUV or other complicated formats
+ * for framebuffers. This means only legacy formats
+ * are supported (fmt->depth is a legacy field), but
+ * the framebuffer emulation can only deal with such
+ * formats, specifically RGB/BGA formats.
+ */
+ format = drm_mode_legacy_fb_format(bpp, depth);
+ if (!format)
+ goto err;
+
+ for (i = 0; i < format_count; ++i) {
+ if (formats[i] == format)
+ return format;
+ }
+
+err:
+ /* We found nothing. */
+ drm_warn(dev, "bpp/depth value of %u/%u not supported\n", bpp, depth);
+
+ return DRM_FORMAT_INVALID;
+}
+
+static uint32_t drm_fb_helper_find_cmdline_format(struct drm_fb_helper *fb_helper,
+ const uint32_t *formats, size_t format_count,
+ const struct drm_cmdline_mode *cmdline_mode)
+{
+ struct drm_device *dev = fb_helper->dev;
+ uint32_t bpp, depth;
+
+ if (!cmdline_mode->bpp_specified)
+ return DRM_FORMAT_INVALID;
+
+ switch (cmdline_mode->bpp) {
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ case 16:
+ case 24:
+ bpp = depth = cmdline_mode->bpp;
+ break;
+ case 15:
+ bpp = 16;
+ depth = 15;
+ break;
+ case 32:
+ bpp = 32;
+ depth = 24;
+ break;
+ default:
+ drm_info(dev, "unsupported bpp value of %d\n", cmdline_mode->bpp);
+ return DRM_FORMAT_INVALID;
+ }
+
+ return drm_fb_helper_find_format(fb_helper, formats, format_count, bpp, depth);
+}
static int __drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper, int preferred_bpp,
struct drm_fb_helper_surface_size *sizes)
@@ -1736,100 +1800,52 @@ static int __drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper, int prefe
struct drm_connector_list_iter conn_iter;
struct drm_connector *connector;
struct drm_mode_set *mode_set;
- int best_depth = 0;
+ uint32_t surface_format = DRM_FORMAT_INVALID;
+ const struct drm_format_info *info;
- memset(sizes, 0, sizeof(struct drm_fb_helper_surface_size));
- sizes->surface_depth = 24;
- sizes->surface_bpp = 32;
+ memset(sizes, 0, sizeof(*sizes));
sizes->fb_width = (u32)-1;
sizes->fb_height = (u32)-1;
- /*
- * If driver picks 8 or 16 by default use that for both depth/bpp
- * to begin with
- */
- if (preferred_bpp != sizes->surface_bpp)
- sizes->surface_depth = sizes->surface_bpp = preferred_bpp;
-
- drm_connector_list_iter_begin(fb_helper->dev, &conn_iter);
- drm_client_for_each_connector_iter(connector, &conn_iter) {
- struct drm_cmdline_mode *cmdline_mode;
-
- cmdline_mode = &connector->cmdline_mode;
-
- if (cmdline_mode->bpp_specified) {
- switch (cmdline_mode->bpp) {
- case 8:
- sizes->surface_depth = sizes->surface_bpp = 8;
- break;
- case 15:
- sizes->surface_depth = 15;
- sizes->surface_bpp = 16;
- break;
- case 16:
- sizes->surface_depth = sizes->surface_bpp = 16;
- break;
- case 24:
- sizes->surface_depth = sizes->surface_bpp = 24;
- break;
- case 32:
- sizes->surface_depth = 24;
- sizes->surface_bpp = 32;
- break;
- }
- break;
- }
- }
- drm_connector_list_iter_end(&conn_iter);
-
- /*
- * If we run into a situation where, for example, the primary plane
- * supports RGBA5551 (16 bpp, depth 15) but not RGB565 (16 bpp, depth
- * 16) we need to scale down the depth of the sizes we request.
- */
drm_client_for_each_modeset(mode_set, client) {
struct drm_crtc *crtc = mode_set->crtc;
struct drm_plane *plane = crtc->primary;
- int j;
drm_dbg_kms(dev, "test CRTC %u primary plane\n", drm_crtc_index(crtc));
- for (j = 0; j < plane->format_count; j++) {
- const struct drm_format_info *fmt;
-
- fmt = drm_format_info(plane->format_types[j]);
+ drm_connector_list_iter_begin(fb_helper->dev, &conn_iter);
+ drm_client_for_each_connector_iter(connector, &conn_iter) {
+ struct drm_cmdline_mode *cmdline_mode = &connector->cmdline_mode;
- /*
- * Do not consider YUV or other complicated formats
- * for framebuffers. This means only legacy formats
- * are supported (fmt->depth is a legacy field) but
- * the framebuffer emulation can only deal with such
- * formats, specifically RGB/BGA formats.
- */
- if (fmt->depth == 0)
- continue;
-
- /* We found a perfect fit, great */
- if (fmt->depth == sizes->surface_depth) {
- best_depth = fmt->depth;
- break;
- }
+ surface_format = drm_fb_helper_find_cmdline_format(fb_helper,
+ plane->format_types,
+ plane->format_count,
+ cmdline_mode);
+ if (surface_format != DRM_FORMAT_INVALID)
+ break; /* found supported format */
+ }
+ drm_connector_list_iter_end(&conn_iter);
- /* Skip depths above what we're looking for */
- if (fmt->depth > sizes->surface_depth)
- continue;
+ if (surface_format != DRM_FORMAT_INVALID)
+ break; /* found supported format */
- /* Best depth found so far */
- if (fmt->depth > best_depth)
- best_depth = fmt->depth;
- }
+ /* try preferred bpp/depth */
+ surface_format = drm_fb_helper_find_format(fb_helper, plane->format_types,
+ plane->format_count, preferred_bpp,
+ dev->mode_config.preferred_depth);
+ if (surface_format != DRM_FORMAT_INVALID)
+ break; /* found supported format */
}
- if (sizes->surface_depth != best_depth && best_depth) {
- drm_info(dev, "requested bpp %d, scaled depth down to %d",
- sizes->surface_bpp, best_depth);
- sizes->surface_depth = best_depth;
+
+ if (surface_format == DRM_FORMAT_INVALID) {
+ drm_warn(dev, "No compatible format found\n");
+ return -EAGAIN;
}
+ info = drm_format_info(surface_format);
+ sizes->surface_bpp = drm_format_info_bpp(info, 0);
+ sizes->surface_depth = info->depth;
+
/* first up get a count of crtcs now in use and new min/maxes width/heights */
crtc_count = 0;
drm_client_for_each_modeset(mode_set, client) {
--
2.38.1
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