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[2/9] drm/i915: Support PCH no display

Message ID 1363198868-21787-3-git-send-email-ben@bwidawsk.net (mailing list archive)
State New, archived
Headers show

Commit Message

Ben Widawsky March 13, 2013, 6:21 p.m. UTC
GEN supports a fusing option which subtracts the PCH display (making the
CPU display also useless). In this configuration MMIO which gets decoded
to a certain range will hang the CPU.

For us, this is sort of the equivalent of having no pipes, and we can
easily modify some code to not do certain things with no pipes.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_dma.c      | 20 ++++++++++++++------
 drivers/gpu/drm/i915/intel_crt.c     |  3 +++
 drivers/gpu/drm/i915/intel_display.c | 10 ++++++++--
 drivers/gpu/drm/i915/intel_fb.c      |  3 +++
 drivers/gpu/drm/i915/intel_overlay.c |  3 +++
 5 files changed, 31 insertions(+), 8 deletions(-)

Comments

Daniel Vetter March 17, 2013, 9:13 p.m. UTC | #1
On Wed, Mar 13, 2013 at 11:21:01AM -0700, Ben Widawsky wrote:
> GEN supports a fusing option which subtracts the PCH display (making the
> CPU display also useless). In this configuration MMIO which gets decoded
> to a certain range will hang the CPU.
> 
> For us, this is sort of the equivalent of having no pipes, and we can
> easily modify some code to not do certain things with no pipes.
> 
> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> ---
>  drivers/gpu/drm/i915/i915_dma.c      | 20 ++++++++++++++------
>  drivers/gpu/drm/i915/intel_crt.c     |  3 +++
>  drivers/gpu/drm/i915/intel_display.c | 10 ++++++++--
>  drivers/gpu/drm/i915/intel_fb.c      |  3 +++
>  drivers/gpu/drm/i915/intel_overlay.c |  3 +++
>  5 files changed, 31 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index ebcfe2e..d925504 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -1322,6 +1322,10 @@ static int i915_load_modeset_init(struct drm_device *dev)
>  	/* Always safe in the mode setting case. */
>  	/* FIXME: do pre/post-mode set stuff in core KMS code */
>  	dev->vblank_disable_allowed = 1;
> +	if (INTEL_INFO(dev)->num_pipes == 0) {
> +		dev_priv->mm.suspended = 0;
> +		return 0;
> +	}
>  
>  	ret = intel_fbdev_init(dev);
>  	if (ret)
> @@ -1630,9 +1634,11 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  	mutex_init(&dev_priv->rps.hw_lock);
>  	mutex_init(&dev_priv->modeset_restore_lock);
>  
> -	ret = drm_vblank_init(dev, INTEL_INFO(dev)->num_pipes);
> -	if (ret)
> -		goto out_gem_unload;
> +	if (INTEL_INFO(dev)->num_pipes) {
> +		ret = drm_vblank_init(dev, INTEL_INFO(dev)->num_pipes);
> +		if (ret)
> +			goto out_gem_unload;
> +	}
>  
>  	/* Start out suspended */
>  	dev_priv->mm.suspended = 1;
> @@ -1647,9 +1653,11 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  
>  	i915_setup_sysfs(dev);
>  
> -	/* Must be done after probing outputs */
> -	intel_opregion_init(dev);
> -	acpi_video_register();
> +	if (INTEL_INFO(dev)->num_pipes) {
> +		/* Must be done after probing outputs */
> +		intel_opregion_init(dev);
> +		acpi_video_register();
> +	}
>  
>  	if (IS_GEN5(dev))
>  		intel_gpu_ips_init(dev_priv);
> diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
> index cfc9687..e794c6c 100644
> --- a/drivers/gpu/drm/i915/intel_crt.c
> +++ b/drivers/gpu/drm/i915/intel_crt.c
> @@ -736,6 +736,9 @@ void intel_crt_init(struct drm_device *dev)
>  	if (dmi_check_system(intel_no_crt))
>  		return;
>  
> +	if (INTEL_INFO(dev)->num_pipes == 0)
> +		return;

Imo better to move this up in the callchain since we should never ever
bother to probe connectors with no pipes.

> +
>  	crt = kzalloc(sizeof(struct intel_crt), GFP_KERNEL);
>  	if (!crt)
>  		return;
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 23379e7..d6dbffd 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -7682,6 +7682,9 @@ intel_modeset_check_state(struct drm_device *dev)
>  	struct intel_encoder *encoder;
>  	struct intel_connector *connector;
>  
> +	if (INTEL_INFO(dev)->num_pipes == 0)
> +		return;

Presuming our works correctly this should never be called if there's no
pipes. Could be that the lid handler is offending us, but that one
shouldn't be registered without a panel. Can you please check whether we
really need this?

> +
>  	list_for_each_entry(connector, &dev->mode_config.connector_list,
>  			    base.head) {
>  		/* This also checks the encoder/connector hw state with the
> @@ -8326,7 +8329,9 @@ static void intel_setup_outputs(struct drm_device *dev)
>  	if (!(HAS_DDI(dev) && (I915_READ(DDI_BUF_CTL(PORT_A)) & DDI_A_4_LANES)))
>  		intel_crt_init(dev);
>  
> -	if (HAS_DDI(dev)) {
> +	if (INTEL_INFO(dev)->num_pipes == 0) {
> +		DRM_DEBUG_KMS("Skipping output detection\n");

Move this up and add an early return, then all the other output checks
should be redundant. There's some other stuff called from
intel_modeset_init which might need to be guarded.

> +	} else if (HAS_DDI(dev)) {
>  		int found;
>  
>  		/* Haswell uses DDI functions to detect digital outputs */
> @@ -8443,7 +8448,8 @@ static void intel_setup_outputs(struct drm_device *dev)
>  
>  	intel_init_pch_refclk(dev);

If you drop everything in setup_outputs you also don't have to deal with
the pch_refclock stuff.

Cheers, Daniel

> -	drm_helper_move_panel_connectors_to_head(dev);
> +	if (INTEL_INFO(dev)->num_pipes)
> +		drm_helper_move_panel_connectors_to_head(dev);
>  }
>  
>  static void intel_user_framebuffer_destroy(struct drm_framebuffer *fb)
> diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c
> index dcdb1d3..5f825c2 100644
> --- a/drivers/gpu/drm/i915/intel_fb.c
> +++ b/drivers/gpu/drm/i915/intel_fb.c
> @@ -295,6 +295,9 @@ void intel_fb_restore_mode(struct drm_device *dev)
>  	struct drm_mode_config *config = &dev->mode_config;
>  	struct drm_plane *plane;
>  
> +	if (!INTEL_INFO(dev)->num_pipes)
> +		return;
> +
>  	drm_modeset_lock_all(dev);
>  
>  	ret = drm_fb_helper_restore_fbdev_mode(&dev_priv->fbdev->helper);
> diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
> index 67a2501..e7fbf2e 100644
> --- a/drivers/gpu/drm/i915/intel_overlay.c
> +++ b/drivers/gpu/drm/i915/intel_overlay.c
> @@ -1323,6 +1323,9 @@ void intel_setup_overlay(struct drm_device *dev)
>  	if (!HAS_OVERLAY(dev))
>  		return;
>  
> +	if (INTEL_INFO(dev)->num_pipes == 0)
> +		return;
> +
>  	overlay = kzalloc(sizeof(struct intel_overlay), GFP_KERNEL);
>  	if (!overlay)
>  		return;
> -- 
> 1.8.1.5
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index ebcfe2e..d925504 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1322,6 +1322,10 @@  static int i915_load_modeset_init(struct drm_device *dev)
 	/* Always safe in the mode setting case. */
 	/* FIXME: do pre/post-mode set stuff in core KMS code */
 	dev->vblank_disable_allowed = 1;
+	if (INTEL_INFO(dev)->num_pipes == 0) {
+		dev_priv->mm.suspended = 0;
+		return 0;
+	}
 
 	ret = intel_fbdev_init(dev);
 	if (ret)
@@ -1630,9 +1634,11 @@  int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	mutex_init(&dev_priv->rps.hw_lock);
 	mutex_init(&dev_priv->modeset_restore_lock);
 
-	ret = drm_vblank_init(dev, INTEL_INFO(dev)->num_pipes);
-	if (ret)
-		goto out_gem_unload;
+	if (INTEL_INFO(dev)->num_pipes) {
+		ret = drm_vblank_init(dev, INTEL_INFO(dev)->num_pipes);
+		if (ret)
+			goto out_gem_unload;
+	}
 
 	/* Start out suspended */
 	dev_priv->mm.suspended = 1;
@@ -1647,9 +1653,11 @@  int i915_driver_load(struct drm_device *dev, unsigned long flags)
 
 	i915_setup_sysfs(dev);
 
-	/* Must be done after probing outputs */
-	intel_opregion_init(dev);
-	acpi_video_register();
+	if (INTEL_INFO(dev)->num_pipes) {
+		/* Must be done after probing outputs */
+		intel_opregion_init(dev);
+		acpi_video_register();
+	}
 
 	if (IS_GEN5(dev))
 		intel_gpu_ips_init(dev_priv);
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index cfc9687..e794c6c 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -736,6 +736,9 @@  void intel_crt_init(struct drm_device *dev)
 	if (dmi_check_system(intel_no_crt))
 		return;
 
+	if (INTEL_INFO(dev)->num_pipes == 0)
+		return;
+
 	crt = kzalloc(sizeof(struct intel_crt), GFP_KERNEL);
 	if (!crt)
 		return;
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 23379e7..d6dbffd 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -7682,6 +7682,9 @@  intel_modeset_check_state(struct drm_device *dev)
 	struct intel_encoder *encoder;
 	struct intel_connector *connector;
 
+	if (INTEL_INFO(dev)->num_pipes == 0)
+		return;
+
 	list_for_each_entry(connector, &dev->mode_config.connector_list,
 			    base.head) {
 		/* This also checks the encoder/connector hw state with the
@@ -8326,7 +8329,9 @@  static void intel_setup_outputs(struct drm_device *dev)
 	if (!(HAS_DDI(dev) && (I915_READ(DDI_BUF_CTL(PORT_A)) & DDI_A_4_LANES)))
 		intel_crt_init(dev);
 
-	if (HAS_DDI(dev)) {
+	if (INTEL_INFO(dev)->num_pipes == 0) {
+		DRM_DEBUG_KMS("Skipping output detection\n");
+	} else if (HAS_DDI(dev)) {
 		int found;
 
 		/* Haswell uses DDI functions to detect digital outputs */
@@ -8443,7 +8448,8 @@  static void intel_setup_outputs(struct drm_device *dev)
 
 	intel_init_pch_refclk(dev);
 
-	drm_helper_move_panel_connectors_to_head(dev);
+	if (INTEL_INFO(dev)->num_pipes)
+		drm_helper_move_panel_connectors_to_head(dev);
 }
 
 static void intel_user_framebuffer_destroy(struct drm_framebuffer *fb)
diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c
index dcdb1d3..5f825c2 100644
--- a/drivers/gpu/drm/i915/intel_fb.c
+++ b/drivers/gpu/drm/i915/intel_fb.c
@@ -295,6 +295,9 @@  void intel_fb_restore_mode(struct drm_device *dev)
 	struct drm_mode_config *config = &dev->mode_config;
 	struct drm_plane *plane;
 
+	if (!INTEL_INFO(dev)->num_pipes)
+		return;
+
 	drm_modeset_lock_all(dev);
 
 	ret = drm_fb_helper_restore_fbdev_mode(&dev_priv->fbdev->helper);
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index 67a2501..e7fbf2e 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -1323,6 +1323,9 @@  void intel_setup_overlay(struct drm_device *dev)
 	if (!HAS_OVERLAY(dev))
 		return;
 
+	if (INTEL_INFO(dev)->num_pipes == 0)
+		return;
+
 	overlay = kzalloc(sizeof(struct intel_overlay), GFP_KERNEL);
 	if (!overlay)
 		return;