diff mbox

[5/8] drm/i915: Wrap the preallocated BIOS framebuffer and preserve for KMS fbcon

Message ID 1360149028-13531-5-git-send-email-chris@chris-wilson.co.uk (mailing list archive)
State New, archived
Headers show

Commit Message

Chris Wilson Feb. 6, 2013, 11:10 a.m. UTC
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_dma.c      |    8 +-
 drivers/gpu/drm/i915/i915_drv.h      |    2 +-
 drivers/gpu/drm/i915/intel_display.c |   14 +-
 drivers/gpu/drm/i915/intel_drv.h     |    4 +
 drivers/gpu/drm/i915/intel_fb.c      |  305 +++++++++++++++++++++++++++++++---
 5 files changed, 306 insertions(+), 27 deletions(-)

Comments

Imre Deak March 8, 2013, 12:05 p.m. UTC | #1
On Wed, 2013-02-06 at 11:10 +0000, Chris Wilson wrote:
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
> ---
>  drivers/gpu/drm/i915/i915_dma.c      |    8 +-
>  drivers/gpu/drm/i915/i915_drv.h      |    2 +-
>  drivers/gpu/drm/i915/intel_display.c |   14 +-
>  drivers/gpu/drm/i915/intel_drv.h     |    4 +
>  drivers/gpu/drm/i915/intel_fb.c      |  305 +++++++++++++++++++++++++++++++---
>  5 files changed, 306 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index 4fa6beb..f2b7db7 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -1273,6 +1273,7 @@ static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
>  static int i915_load_modeset_init(struct drm_device *dev)
>  {
>  	struct drm_i915_private *dev_priv = dev->dev_private;
> +	bool was_vga_enabled;
>  	int ret;
>  
>  	ret = intel_parse_bios(dev);
> @@ -1309,7 +1310,11 @@ static int i915_load_modeset_init(struct drm_device *dev)
>  
>  	/* Important: The output setup functions called by modeset_init need
>  	 * working irqs for e.g. gmbus and dp aux transfers. */
> -	intel_modeset_init(dev);
> +	intel_modeset_init(dev, &was_vga_enabled);
> +
> +	/* Wrap existing BIOS mode configuration prior to GEM takeover */
> +	if (!was_vga_enabled)
> +		intel_fbdev_init_bios(dev);
>  
>  	ret = i915_gem_init(dev);
>  	if (ret)
> @@ -1323,6 +1328,7 @@ static int i915_load_modeset_init(struct drm_device *dev)
>  	/* FIXME: do pre/post-mode set stuff in core KMS code */
>  	dev->vblank_disable_allowed = 1;
>  
> +	/* Install a default KMS/GEM fbcon if we failed to wrap the BIOS fb */
>  	ret = intel_fbdev_init(dev);
>  	if (ret)
>  		goto cleanup_gem;
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index fd8a495..6f4afbf 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1814,7 +1814,7 @@ static inline void intel_unregister_dsm_handler(void) { return; }
>  
>  /* modesetting */
>  extern void intel_modeset_init_hw(struct drm_device *dev);
> -extern void intel_modeset_init(struct drm_device *dev);
> +extern void intel_modeset_init(struct drm_device *dev, bool *was_vga_enabled);
>  extern void intel_modeset_gem_init(struct drm_device *dev);
>  extern void intel_modeset_cleanup(struct drm_device *dev);
>  extern int intel_modeset_vga_set_state(struct drm_device *dev, bool state);
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 8f9cdd7..7c4c7d5 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -8698,12 +8698,17 @@ static void intel_init_quirks(struct drm_device *dev)
>  }
>  
>  /* Disable the VGA plane that we never use */
> -static void i915_disable_vga(struct drm_device *dev)
> +static bool i915_disable_vga(struct drm_device *dev)
>  {
>  	struct drm_i915_private *dev_priv = dev->dev_private;
> +	bool was_enabled;
>  	u8 sr1;
>  	u32 vga_reg = i915_vgacntrl_reg(dev);
>  
> +	was_enabled = !(I915_READ(vga_reg) & VGA_DISP_DISABLE);
> +	DRM_DEBUG_KMS("VGA output is currently %s\n",
> +		      was_enabled ? "enabled" : "disabled");
> +
>  	vga_get_uninterruptible(dev->pdev, VGA_RSRC_LEGACY_IO);
>  	outb(SR01, VGA_SR_INDEX);
>  	sr1 = inb(VGA_SR_DATA);
> @@ -8713,6 +8718,8 @@ static void i915_disable_vga(struct drm_device *dev)
>  
>  	I915_WRITE(vga_reg, VGA_DISP_DISABLE);
>  	POSTING_READ(vga_reg);
> +
> +	return was_enabled;
>  }
>  
>  void intel_modeset_init_hw(struct drm_device *dev)
> @@ -8728,7 +8735,8 @@ void intel_modeset_init_hw(struct drm_device *dev)
>  	mutex_unlock(&dev->struct_mutex);
>  }
>  
> -void intel_modeset_init(struct drm_device *dev)
> +void intel_modeset_init(struct drm_device *dev,
> +			bool *was_vga_enabled)
>  {
>  	struct drm_i915_private *dev_priv = dev->dev_private;
>  	int i, ret;
> @@ -8775,7 +8783,7 @@ void intel_modeset_init(struct drm_device *dev)
>  	intel_pch_pll_init(dev);
>  
>  	/* Just disable it once at startup */
> -	i915_disable_vga(dev);
> +	*was_vga_enabled = i915_disable_vga(dev);
>  	intel_setup_outputs(dev);
>  
>  	/* Just in case the BIOS is doing something questionable. */
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 07d95a1..985e9dd 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -146,6 +146,8 @@ struct intel_fbdev {
>  	struct intel_framebuffer ifb;
>  	struct list_head fbdev_list;
>  	struct drm_display_mode *our_mode;
> +	bool stolen;
> +	int preferred_bpp;
>  };
>  
>  struct intel_encoder {
> @@ -212,6 +214,7 @@ struct intel_crtc {
>  	enum plane plane;
>  	enum transcoder cpu_transcoder;
>  	u8 lut_r[256], lut_g[256], lut_b[256];
> +	bool mode_valid;
>  	/*
>  	 * Whether the crtc and the connected output pipeline is active. Implies
>  	 * that crtc->enabled is set, i.e. the current mode configuration has
> @@ -612,6 +615,7 @@ extern int intel_framebuffer_init(struct drm_device *dev,
>  				  struct intel_framebuffer *ifb,
>  				  struct drm_mode_fb_cmd2 *mode_cmd,
>  				  struct drm_i915_gem_object *obj);
> +extern void intel_fbdev_init_bios(struct drm_device *dev);
>  extern int intel_fbdev_init(struct drm_device *dev);
>  extern void intel_fbdev_initial_config(struct drm_device *dev);
>  extern void intel_fbdev_fini(struct drm_device *dev);
> diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c
> index de0ac4c..ca6c8e6 100644
> --- a/drivers/gpu/drm/i915/intel_fb.c
> +++ b/drivers/gpu/drm/i915/intel_fb.c
> @@ -131,7 +131,6 @@ static int intelfb_create(struct intel_fbdev *ifbdev,
>  	struct drm_device *dev = ifbdev->helper.dev;
>  	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
>  	struct drm_i915_gem_object *obj;
> -	struct fb_info *info;
>  	int size, ret;
>  
>  	/* we don't do packed 24bpp */
> @@ -176,14 +175,7 @@ static int intelfb_create(struct intel_fbdev *ifbdev,
>  		      mode_cmd.width, mode_cmd.height,
>  		      obj->gtt_offset, obj);
>  
> -	info = intelfb_create_info(ifbdev);
> -	if (info == NULL) {
> -		ret = -ENOMEM;
> -		goto out_unpin;
> -	}
> -
>  	mutex_unlock(&dev->struct_mutex);
> -	vga_switcheroo_client_fb_set(dev->pdev, info);
>  	return 0;
>  
>  out_unpin:
> @@ -200,17 +192,92 @@ static int intel_fb_find_or_create_single(struct drm_fb_helper *helper,
>  {
>  	struct intel_fbdev *ifbdev = (struct intel_fbdev *)helper;
>  	int new_fb = 0;
> -	int ret;
>  
>  	if (!helper->fb) {
> -		ret = intelfb_create(ifbdev, sizes);
> -		if (ret)
> -			return ret;
> +		struct fb_info *info;
> +
> +		if (!ifbdev->stolen) {
> +			int ret = intelfb_create(ifbdev, sizes);
> +			if (ret)
> +				return ret;
> +		}
> +
> +		info = intelfb_create_info(ifbdev);
> +		if (info == NULL) {
> +			DRM_DEBUG_KMS("fb creation failed\n");
> +			return -ENOMEM;
> +		}
> +		vga_switcheroo_client_fb_set(helper->dev->pdev, info);
> +
>  		new_fb = 1;
>  	}
> +
>  	return new_fb;
>  }
>  
> +static struct drm_fb_helper_crtc *
> +intel_fb_helper_crtc(struct drm_fb_helper *fb_helper, struct drm_crtc *crtc)
> +{
> +	int i;
> +
> +	for (i = 0; i < fb_helper->crtc_count; i++)
> +		if (fb_helper->crtc_info[i].mode_set.crtc == crtc)
> +			return &fb_helper->crtc_info[i];
> +
> +	return NULL;
> +}
> +
> +static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
> +				    struct drm_fb_helper_crtc **crtcs,
> +				    struct drm_display_mode **modes,
> +				    bool *enabled, int width, int height)
> +{
> +	int i;
> +
> +	for (i = 0; i < fb_helper->connector_count; i++) {
> +		struct drm_connector *connector;
> +		struct drm_encoder *encoder;
> +
> +		connector = fb_helper->connector_info[i]->connector;
> +		if (!enabled[i]) {
> +			DRM_DEBUG_KMS("connector %d not enabled, skipping\n",
> +				      connector->base.id);
> +			continue;
> +		}
> +
> +		encoder = connector->encoder;
> +		if (!encoder || !encoder->crtc) {
> +			DRM_DEBUG_KMS("connector %d has no encoder or crtc, skipping\n",
> +				      connector->base.id);
> +			continue;
> +		}
> +
> +		if (WARN_ON(!encoder->crtc->enabled)) {
> +			DRM_DEBUG_KMS("connector %s on crtc %d has inconsistent state, aborting\n",
> +				      drm_get_connector_name(connector),
> +				      encoder->crtc->base.id);
> +			return false;
> +		}
> +
> +		if (!to_intel_crtc(encoder->crtc)->mode_valid) {
> +			DRM_DEBUG_KMS("connector %s on crtc %d has an invalid mode, aborting\n",
> +				      drm_get_connector_name(connector),
> +				      encoder->crtc->base.id);
> +			return false;
> +		}
> +
> +		modes[i] = &encoder->crtc->mode;

I might be missing something, but I can't see how crtc->mode will be
valid at this point. We'll get here through
intel_fb_initial_config()->drm_setup_crtcs() but as I understand
crtc->mode will only be set afterwards through
intel_fb_initial_config()->drm_fb_helper_single_fb_probe().

At least testing on my ILK I get here with mode_valid=false.

--Imre
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 4fa6beb..f2b7db7 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1273,6 +1273,7 @@  static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
 static int i915_load_modeset_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	bool was_vga_enabled;
 	int ret;
 
 	ret = intel_parse_bios(dev);
@@ -1309,7 +1310,11 @@  static int i915_load_modeset_init(struct drm_device *dev)
 
 	/* Important: The output setup functions called by modeset_init need
 	 * working irqs for e.g. gmbus and dp aux transfers. */
-	intel_modeset_init(dev);
+	intel_modeset_init(dev, &was_vga_enabled);
+
+	/* Wrap existing BIOS mode configuration prior to GEM takeover */
+	if (!was_vga_enabled)
+		intel_fbdev_init_bios(dev);
 
 	ret = i915_gem_init(dev);
 	if (ret)
@@ -1323,6 +1328,7 @@  static int i915_load_modeset_init(struct drm_device *dev)
 	/* FIXME: do pre/post-mode set stuff in core KMS code */
 	dev->vblank_disable_allowed = 1;
 
+	/* Install a default KMS/GEM fbcon if we failed to wrap the BIOS fb */
 	ret = intel_fbdev_init(dev);
 	if (ret)
 		goto cleanup_gem;
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index fd8a495..6f4afbf 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1814,7 +1814,7 @@  static inline void intel_unregister_dsm_handler(void) { return; }
 
 /* modesetting */
 extern void intel_modeset_init_hw(struct drm_device *dev);
-extern void intel_modeset_init(struct drm_device *dev);
+extern void intel_modeset_init(struct drm_device *dev, bool *was_vga_enabled);
 extern void intel_modeset_gem_init(struct drm_device *dev);
 extern void intel_modeset_cleanup(struct drm_device *dev);
 extern int intel_modeset_vga_set_state(struct drm_device *dev, bool state);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8f9cdd7..7c4c7d5 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8698,12 +8698,17 @@  static void intel_init_quirks(struct drm_device *dev)
 }
 
 /* Disable the VGA plane that we never use */
-static void i915_disable_vga(struct drm_device *dev)
+static bool i915_disable_vga(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	bool was_enabled;
 	u8 sr1;
 	u32 vga_reg = i915_vgacntrl_reg(dev);
 
+	was_enabled = !(I915_READ(vga_reg) & VGA_DISP_DISABLE);
+	DRM_DEBUG_KMS("VGA output is currently %s\n",
+		      was_enabled ? "enabled" : "disabled");
+
 	vga_get_uninterruptible(dev->pdev, VGA_RSRC_LEGACY_IO);
 	outb(SR01, VGA_SR_INDEX);
 	sr1 = inb(VGA_SR_DATA);
@@ -8713,6 +8718,8 @@  static void i915_disable_vga(struct drm_device *dev)
 
 	I915_WRITE(vga_reg, VGA_DISP_DISABLE);
 	POSTING_READ(vga_reg);
+
+	return was_enabled;
 }
 
 void intel_modeset_init_hw(struct drm_device *dev)
@@ -8728,7 +8735,8 @@  void intel_modeset_init_hw(struct drm_device *dev)
 	mutex_unlock(&dev->struct_mutex);
 }
 
-void intel_modeset_init(struct drm_device *dev)
+void intel_modeset_init(struct drm_device *dev,
+			bool *was_vga_enabled)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	int i, ret;
@@ -8775,7 +8783,7 @@  void intel_modeset_init(struct drm_device *dev)
 	intel_pch_pll_init(dev);
 
 	/* Just disable it once at startup */
-	i915_disable_vga(dev);
+	*was_vga_enabled = i915_disable_vga(dev);
 	intel_setup_outputs(dev);
 
 	/* Just in case the BIOS is doing something questionable. */
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 07d95a1..985e9dd 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -146,6 +146,8 @@  struct intel_fbdev {
 	struct intel_framebuffer ifb;
 	struct list_head fbdev_list;
 	struct drm_display_mode *our_mode;
+	bool stolen;
+	int preferred_bpp;
 };
 
 struct intel_encoder {
@@ -212,6 +214,7 @@  struct intel_crtc {
 	enum plane plane;
 	enum transcoder cpu_transcoder;
 	u8 lut_r[256], lut_g[256], lut_b[256];
+	bool mode_valid;
 	/*
 	 * Whether the crtc and the connected output pipeline is active. Implies
 	 * that crtc->enabled is set, i.e. the current mode configuration has
@@ -612,6 +615,7 @@  extern int intel_framebuffer_init(struct drm_device *dev,
 				  struct intel_framebuffer *ifb,
 				  struct drm_mode_fb_cmd2 *mode_cmd,
 				  struct drm_i915_gem_object *obj);
+extern void intel_fbdev_init_bios(struct drm_device *dev);
 extern int intel_fbdev_init(struct drm_device *dev);
 extern void intel_fbdev_initial_config(struct drm_device *dev);
 extern void intel_fbdev_fini(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c
index de0ac4c..ca6c8e6 100644
--- a/drivers/gpu/drm/i915/intel_fb.c
+++ b/drivers/gpu/drm/i915/intel_fb.c
@@ -131,7 +131,6 @@  static int intelfb_create(struct intel_fbdev *ifbdev,
 	struct drm_device *dev = ifbdev->helper.dev;
 	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
 	struct drm_i915_gem_object *obj;
-	struct fb_info *info;
 	int size, ret;
 
 	/* we don't do packed 24bpp */
@@ -176,14 +175,7 @@  static int intelfb_create(struct intel_fbdev *ifbdev,
 		      mode_cmd.width, mode_cmd.height,
 		      obj->gtt_offset, obj);
 
-	info = intelfb_create_info(ifbdev);
-	if (info == NULL) {
-		ret = -ENOMEM;
-		goto out_unpin;
-	}
-
 	mutex_unlock(&dev->struct_mutex);
-	vga_switcheroo_client_fb_set(dev->pdev, info);
 	return 0;
 
 out_unpin:
@@ -200,17 +192,92 @@  static int intel_fb_find_or_create_single(struct drm_fb_helper *helper,
 {
 	struct intel_fbdev *ifbdev = (struct intel_fbdev *)helper;
 	int new_fb = 0;
-	int ret;
 
 	if (!helper->fb) {
-		ret = intelfb_create(ifbdev, sizes);
-		if (ret)
-			return ret;
+		struct fb_info *info;
+
+		if (!ifbdev->stolen) {
+			int ret = intelfb_create(ifbdev, sizes);
+			if (ret)
+				return ret;
+		}
+
+		info = intelfb_create_info(ifbdev);
+		if (info == NULL) {
+			DRM_DEBUG_KMS("fb creation failed\n");
+			return -ENOMEM;
+		}
+		vga_switcheroo_client_fb_set(helper->dev->pdev, info);
+
 		new_fb = 1;
 	}
+
 	return new_fb;
 }
 
+static struct drm_fb_helper_crtc *
+intel_fb_helper_crtc(struct drm_fb_helper *fb_helper, struct drm_crtc *crtc)
+{
+	int i;
+
+	for (i = 0; i < fb_helper->crtc_count; i++)
+		if (fb_helper->crtc_info[i].mode_set.crtc == crtc)
+			return &fb_helper->crtc_info[i];
+
+	return NULL;
+}
+
+static bool intel_fb_initial_config(struct drm_fb_helper *fb_helper,
+				    struct drm_fb_helper_crtc **crtcs,
+				    struct drm_display_mode **modes,
+				    bool *enabled, int width, int height)
+{
+	int i;
+
+	for (i = 0; i < fb_helper->connector_count; i++) {
+		struct drm_connector *connector;
+		struct drm_encoder *encoder;
+
+		connector = fb_helper->connector_info[i]->connector;
+		if (!enabled[i]) {
+			DRM_DEBUG_KMS("connector %d not enabled, skipping\n",
+				      connector->base.id);
+			continue;
+		}
+
+		encoder = connector->encoder;
+		if (!encoder || !encoder->crtc) {
+			DRM_DEBUG_KMS("connector %d has no encoder or crtc, skipping\n",
+				      connector->base.id);
+			continue;
+		}
+
+		if (WARN_ON(!encoder->crtc->enabled)) {
+			DRM_DEBUG_KMS("connector %s on crtc %d has inconsistent state, aborting\n",
+				      drm_get_connector_name(connector),
+				      encoder->crtc->base.id);
+			return false;
+		}
+
+		if (!to_intel_crtc(encoder->crtc)->mode_valid) {
+			DRM_DEBUG_KMS("connector %s on crtc %d has an invalid mode, aborting\n",
+				      drm_get_connector_name(connector),
+				      encoder->crtc->base.id);
+			return false;
+		}
+
+		modes[i] = &encoder->crtc->mode;
+		crtcs[i] = intel_fb_helper_crtc(fb_helper, encoder->crtc);
+
+		DRM_DEBUG_KMS("connector %s on crtc %d: %s\n",
+			      drm_get_connector_name(connector),
+			      encoder->crtc->base.id,
+			      modes[i]->name);
+	}
+
+	return true;
+}
+
 static struct drm_fb_helper_funcs intel_fb_helper_funcs = {
 	.gamma_set = intel_crtc_fb_gamma_set,
 	.gamma_get = intel_crtc_fb_gamma_get,
@@ -241,23 +308,215 @@  static void intel_fbdev_destroy(struct drm_device *dev,
 	}
 }
 
-int intel_fbdev_init(struct drm_device *dev)
+static bool pipe_enabled(struct drm_i915_private *dev_priv, enum pipe pipe)
 {
+	enum transcoder cpu_transcoder =
+		intel_pipe_to_cpu_transcoder(dev_priv, pipe);
+	return !!(I915_READ(PIPECONF(cpu_transcoder)) & PIPECONF_ENABLE);
+}
+
+/*
+ * Try to read the BIOS display configuration and use it for the initial
+ * fb configuration.
+ *
+ * The BIOS or boot loader will generally create an initial display
+ * configuration for us that includes some set of active pipes and displays.
+ * This routine tries to figure out which pipes are active, what resolutions
+ * are being displayed, and then allocates a framebuffer and initial fb
+ * config based on that data.
+ *
+ * If the BIOS or boot loader leaves the display in VGA mode, there's not
+ * much we can do; switching out of that mode involves allocating a new,
+ * high res buffer, and also recalculating bandwidth requirements for the
+ * new bpp configuration.
+ *
+ * However, if we're loaded into an existing, high res mode, we should
+ * be able to allocate a buffer big enough to handle the largest active
+ * mode, create a mode_set for it, and pass it to the fb helper to create
+ * the configuration.
+ */
+void intel_fbdev_init_bios(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_fbdev *ifbdev;
-	drm_i915_private_t *dev_priv = dev->dev_private;
-	int ret;
+	struct drm_crtc *crtc;
+	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
+	struct drm_i915_gem_object *obj;
+	u32 obj_offset = 0;
+	int mode_bpp = 0;
+	u32 active = 0;
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+		struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+		int pipe = intel_crtc->pipe, plane = intel_crtc->plane;
+		u32 val, bpp, offset, format;
+		int pitch, width, height;
+
+		if (!pipe_enabled(dev_priv, pipe)) {
+			DRM_DEBUG_KMS("pipe %c not active, skipping\n",
+				      pipe_name(pipe));
+			continue;
+		}
+
+		val = I915_READ(DSPCNTR(plane));
+
+		if (INTEL_INFO(dev)->gen >= 4) {
+			if (val & DISPPLANE_TILED) {
+				DRM_DEBUG_KMS("tiled BIOS fb?\n");
+				continue; /* unexpected! */
+			}
+		}
+
+		switch (val & DISPPLANE_PIXFORMAT_MASK) {
+		case DISPPLANE_YUV422:
+		default:
+			DRM_DEBUG_KMS("pipe %c unsupported pixel format %x, skipping\n",
+				      pipe_name(pipe), (val & DISPPLANE_PIXFORMAT_MASK) >> 26);
+			continue;
+		case DISPPLANE_8BPP:
+			format = DRM_FORMAT_C8;
+			bpp = 8;
+			break;
+		case DISPPLANE_BGRX555:
+			format = DRM_FORMAT_XRGB1555;
+			bpp = 16;
+			break;
+		case DISPPLANE_BGRX565:
+			format = DRM_FORMAT_RGB565;
+			bpp = 16;
+			break;
+		case DISPPLANE_BGRX888:
+			format = DRM_FORMAT_XRGB8888;
+			bpp = 32;
+			break;
+		}
+
+		if (mode_cmd.pixel_format == 0) {
+			mode_bpp = bpp;
+			mode_cmd.pixel_format = format;
+		}
+
+		if (mode_cmd.pixel_format != format) {
+			DRM_DEBUG_KMS("pipe %c has format/bpp (%d, %d) mismatch: skipping\n",
+				      pipe_name(pipe), format, bpp);
+			continue;
+		}
+
+		if (INTEL_INFO(dev)->gen >= 4) {
+			if (I915_READ(DSPTILEOFF(plane))) {
+				DRM_DEBUG_KMS("pipe %c is offset: skipping\n",
+					      pipe_name(pipe));
+				continue;
+			}
+
+			offset = I915_READ(DSPSURF(plane));
+		} else
+			offset = I915_READ(DSPADDR(plane));
+		if (!obj_offset)
+			obj_offset = offset;
+
+		pitch = I915_READ(DSPSTRIDE(plane));
+		if (mode_cmd.pitches[0] == 0)
+			mode_cmd.pitches[0] = pitch;
+
+		if (offset != obj_offset || pitch != mode_cmd.pitches[0]) {
+			DRM_DEBUG_KMS("multiple pipe setup not in clone mode, sjipping\n");
+			continue;
+		}
+
+		val = I915_READ(PIPESRC(pipe));
+		width = ((val >> 16) & 0xfff) + 1;
+		height = ((val >> 0) & 0xfff) + 1;
+
+		DRM_DEBUG_KMS("Found active pipe [%d/%d]: size=%dx%d@%d, offset=%x\n",
+			      pipe, plane, width, height, bpp, offset);
+
+		if (width > mode_cmd.width)
+			mode_cmd.width = width;
+
+		if (height > mode_cmd.height)
+			mode_cmd.height = height;
+
+		active |= 1 << pipe;
+	}
+
+	if (active == 0) {
+		DRM_DEBUG_KMS("no active pipes found, not using BIOS config\n");
+		return;
+	}
 
 	ifbdev = kzalloc(sizeof(struct intel_fbdev), GFP_KERNEL);
-	if (!ifbdev)
-		return -ENOMEM;
+	if (ifbdev == NULL) {
+		DRM_DEBUG_KMS("failed to alloc intel fbdev\n");
+		return;
+	}
 
-	dev_priv->fbdev = ifbdev;
+	ifbdev->stolen = true;
+	ifbdev->preferred_bpp = mode_bpp;
 	ifbdev->helper.funcs = &intel_fb_helper_funcs;
+	ifbdev->helper.funcs->initial_config = intel_fb_initial_config;
+
+	/* assume a 1:1 linear mapping between stolen and GTT */
+	obj = i915_gem_object_create_stolen_for_preallocated(dev,
+							     obj_offset,
+							     obj_offset,
+							     ALIGN(mode_cmd.pitches[0] * mode_cmd.height, PAGE_SIZE));
+	if (obj == NULL) {
+		DRM_DEBUG_KMS("failed to create stolen fb\n");
+		goto out_free_ifbdev;
+	}
+
+	if (intel_framebuffer_init(dev, &ifbdev->ifb, &mode_cmd, obj)) {
+		DRM_DEBUG_KMS("intel fb init failed\n");
+		goto out_unref_obj;
+	}
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
+		int ret;
+
+		if ((active & (1 << to_intel_crtc(crtc)->pipe)) == 0)
+			continue;
+
+		ret = intel_pin_and_fence_fb_obj(dev, obj, NULL);
+		if (ret)
+			goto out_unref_obj;
+
+		crtc->fb = &ifbdev->ifb.base;
+	}
+
+	dev_priv->fbdev = ifbdev;
+
+	DRM_DEBUG_KMS("using BIOS fb for initial console\n");
+	return;
+
+out_unref_obj:
+	drm_gem_object_unreference(&obj->base);
+out_free_ifbdev:
+	kfree(ifbdev);
+}
+
+int intel_fbdev_init(struct drm_device *dev)
+{
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct intel_fbdev *ifbdev;
+	int ret;
+
+	if ((ifbdev = dev_priv->fbdev) == NULL) {
+		ifbdev = kzalloc(sizeof(struct intel_fbdev), GFP_KERNEL);
+		if (ifbdev == NULL)
+			return -ENOMEM;
+
+		ifbdev->helper.funcs = &intel_fb_helper_funcs;
+		ifbdev->preferred_bpp = 32;
+
+		dev_priv->fbdev = ifbdev;
+	}
 
 	ret = drm_fb_helper_init(dev, &ifbdev->helper,
-				 dev_priv->num_pipe,
-				 INTELFB_CONN_LIMIT);
+			dev_priv->num_pipe,
+			INTELFB_CONN_LIMIT);
 	if (ret) {
+		dev_priv->fbdev = NULL;
 		kfree(ifbdev);
 		return ret;
 	}
@@ -270,9 +529,10 @@  int intel_fbdev_init(struct drm_device *dev)
 void intel_fbdev_initial_config(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct intel_fbdev *ifbdev = dev_priv->fbdev;
 
 	/* Due to peculiar init order wrt to hpd handling this is separate. */
-	drm_fb_helper_initial_config(&dev_priv->fbdev->helper, 32);
+	drm_fb_helper_initial_config(&ifbdev->helper, ifbdev->preferred_bpp);
 }
 
 void intel_fbdev_fini(struct drm_device *dev)
@@ -300,7 +560,8 @@  MODULE_LICENSE("GPL and additional rights");
 void intel_fb_output_poll_changed(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
-	drm_fb_helper_hotplug_event(&dev_priv->fbdev->helper);
+	if (dev_priv->fbdev)
+		drm_fb_helper_hotplug_event(&dev_priv->fbdev->helper);
 }
 
 void intel_fb_restore_mode(struct drm_device *dev)