From b693e42921e0220c0d564c55c6cdc680b0f85390 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Tue, 5 Oct 2021 09:03:55 +0200 Subject: [PATCH] drm/fbdev: Clamp fbdev surface size if too large MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Clamp the fbdev surface size of the available maximumi height to avoid failing to init console emulation. An example error is shown below. bad framebuffer height 2304, should be >= 768 && <= 768 [drm] Initialized simpledrm 1.0.0 20200625 for simple-framebuffer.0 on minor 0 simple-framebuffer simple-framebuffer.0: [drm] *ERROR* fbdev: Failed to setup generic emulation (ret=-22) This is especially a problem with drivers that have very small screen sizes and cannot over-allocate at all. v2: * reduce warning level (Ville) Signed-off-by: Thomas Zimmermann Fixes: 11e8f5fd223b ("drm: Add simpledrm driver") Reviewed-by: Ville Syrjälä Reviewed-by: Alex Deucher Reported-by: Amanoel Dawod Reported-by: Zoltán Kővágó Reported-by: Michael Stapelberg Cc: Daniel Vetter Cc: Maxime Ripard Cc: dri-devel@lists.freedesktop.org Cc: # v5.14+ Link: https://patchwork.freedesktop.org/patch/msgid/20211005070355.7680-1-tzimmermann@suse.de Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_fb_helper.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 3ab0783..8e7a124 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1506,6 +1506,7 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, { struct drm_client_dev *client = &fb_helper->client; struct drm_device *dev = fb_helper->dev; + struct drm_mode_config *config = &dev->mode_config; int ret = 0; int crtc_count = 0; struct drm_connector_list_iter conn_iter; @@ -1663,6 +1664,11 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, /* Handle our overallocation */ sizes.surface_height *= drm_fbdev_overalloc; sizes.surface_height /= 100; + if (sizes.surface_height > config->max_height) { + drm_dbg_kms(dev, "Fbdev over-allocation too large; clamping height to %d\n", + config->max_height); + sizes.surface_height = config->max_height; + } /* push down into drivers */ ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes); -- 2.7.4