From 58540594570778fd149cd8c9b2bff61f2cefa8c9 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Wed, 3 Jul 2019 09:58:34 +0200 Subject: [PATCH] drm/bochs: Use shadow buffer for bochs framebuffer console MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The bochs driver (and virtual hardware) requires buffer objects to reside in video ram to display them to the screen. So it can not display the framebuffer console because the respective buffer object is permanently pinned in system memory. Using a shadow buffer for the console solves this problem. The console emulation will pin the buffer object only during updates from the shadow buffer. Otherwise, the bochs driver can freely relocated the buffer between system memory and video ram. v2: * select shadow FB via struct drm_mode_config.prefer_shadow_fbdev Signed-off-by: Thomas Zimmermann Acked-by: Noralf Trønnes Link: https://patchwork.freedesktop.org/patch/315833/ Signed-off-by: Gerd Hoffmann --- drivers/gpu/drm/bochs/bochs_kms.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/bochs/bochs_kms.c b/drivers/gpu/drm/bochs/bochs_kms.c index bc19dbd531ef..359030d5d818 100644 --- a/drivers/gpu/drm/bochs/bochs_kms.c +++ b/drivers/gpu/drm/bochs/bochs_kms.c @@ -191,6 +191,7 @@ int bochs_kms_init(struct bochs_device *bochs) bochs->dev->mode_config.fb_base = bochs->fb_base; bochs->dev->mode_config.preferred_depth = 24; bochs->dev->mode_config.prefer_shadow = 0; + bochs->dev->mode_config.prefer_shadow_fbdev = 1; bochs->dev->mode_config.quirk_addfb_prefer_host_byte_order = true; bochs->dev->mode_config.funcs = &bochs_mode_funcs;