Re: [PATCH 3/4] drm/i915: CSC color correction

[Matt Roper <matthew.d.roper@intel.com>]

On Tue, Sep 09, 2014 at 11:53:15AM +0530, shashank.sharma@intel.com wrote:
> From: Shashank Sharma <shashank.sharma@intel.com>
> 
> This patch adds support for CSC correction color property.
> It does the following:
> 1. Creates a new DRM property for CSC correction. Adds this into
>    mode_config.
> 2. Attaches this CSC property to calling CRTC. Creates a blob
>    to store the correction values, and attaches the blob to CRTC.
> 3. Adds function intel_clrmgr_set_csc: This is a wrapper function
>    which checks the platform type, and calls the valleyview
>    specific set_csc function. As different platforms may have different
>    methods of setting CSC, wrapper function is required to route to proper
>    core CSC set function. In future, the support for other platfroms can be
>    plugged-in here. Adding this function as .set_property CSC color property.
> 4. Adds function vlv_set_csc: core function to program CSC coefficients as per
>    vlv specs, and then enable CSC.
> 
> Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>

I haven't read up on the hardware programming side of this code to give
any comments there, but I got a bit lost trying to follow your blob
upload handling here.  Like Bob noted, it kind of looks like you're
trying to add userspace blob property upload functionality that would
really belong in the DRM core.  However, in the intermediate/long term
there probably isn't really a need for this kind of blob upload support
because the atomic propertysets will provide the functionality you need;
once we have atomic support, I think it would be better to just make
each of these values an independent property and upload all of the
values together as part of a single property set.  But I realize you're
specifically trying to add add this support in a pre-atomic world which
makes things more challenging.  Atomic is definitely coming, but I think
the timeframe is kind of uncertain still, so it's really going to be up
to the upstream maintainers on how to proceed.  Maybe Daniel can give
you some direction?


Matt

> ---
>  drivers/gpu/drm/drm_crtc.c          |   4 +-
>  drivers/gpu/drm/i915/i915_reg.h     |  11 ++
>  drivers/gpu/drm/i915/intel_clrmgr.c | 208 +++++++++++++++++++++++++++++++++++-
>  drivers/gpu/drm/i915/intel_clrmgr.h |  16 +++
>  drivers/gpu/drm/i915/intel_drv.h    |   1 +
>  include/drm/drm_crtc.h              |   7 ++
>  6 files changed, 244 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 272b66f..be9d110 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -3917,7 +3917,7 @@ done:
>  	return ret;
>  }
>  
> -static struct drm_property_blob *drm_property_create_blob(struct drm_device *dev, int length,
> +struct drm_property_blob *drm_property_create_blob(struct drm_device *dev, int length,
>  							  void *data)
>  {
>  	struct drm_property_blob *blob;
> @@ -3944,7 +3944,7 @@ static struct drm_property_blob *drm_property_create_blob(struct drm_device *dev
>  	return blob;
>  }
>  
> -static void drm_property_destroy_blob(struct drm_device *dev,
> +void drm_property_destroy_blob(struct drm_device *dev,
>  			       struct drm_property_blob *blob)
>  {
>  	drm_mode_object_put(dev, &blob->base);
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 20673cc..e3010b3 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -6183,6 +6183,17 @@ enum punit_power_well {
>  #define PIPE_CSC_POSTOFF_ME(pipe) _PIPE(pipe, _PIPE_A_CSC_POSTOFF_ME, _PIPE_B_CSC_POSTOFF_ME)
>  #define PIPE_CSC_POSTOFF_LO(pipe) _PIPE(pipe, _PIPE_A_CSC_POSTOFF_LO, _PIPE_B_CSC_POSTOFF_LO)
>  
> +/* VLV color correction registers */
> +/* CSC */
> +#define PIPECONF_CSC_ENABLE	(1 << 15)
> +#define _PIPEACSC		(dev_priv->info.display_mmio_offset + \
> +								0x600b0)
> +#define _PIPEBCSC		(dev_priv->info.display_mmio_offset + \
> +								0x610b0)
> +#define PIPECSC(pipe)		(_PIPEACSC + (pipe *  CSC_OFFSET))
> +#define CSC_OFFSET			(_PIPEBCSC - _PIPEACSC)
> +#define PIPECSC(pipe)		(_PIPEACSC + (pipe *  CSC_OFFSET))
> +
>  /* VLV MIPI registers */
>  
>  #define _MIPIA_PORT_CTRL			(VLV_DISPLAY_BASE + 0x61190)
> diff --git a/drivers/gpu/drm/i915/intel_clrmgr.c b/drivers/gpu/drm/i915/intel_clrmgr.c
> index ac0a890..36c64c1 100644
> --- a/drivers/gpu/drm/i915/intel_clrmgr.c
> +++ b/drivers/gpu/drm/i915/intel_clrmgr.c
> @@ -32,6 +32,138 @@
>  #include "i915_reg.h"
>  #include "intel_clrmgr.h"
>  
> +/*
> +* Names to register with color properties.
> +* Sequence must be the same as the order
> +* of enum clrmgr_tweaks
> +*/
> +const char *clrmgr_property_names[] = {
> +	/* csc */
> +	"csc-correction",
> +	/* add a new prop name here */
> +};
> +
> +
> +/*
> +* Sizes for color properties. This can differ
> +* platform by platform, hence 'vlv' prefix
> +* The sequence must be same as the order of
> +* enum clrmgr_tweaks
> +*/
> +u32 vlv_color_property_sizes[] = {
> +	VLV_CSC_MATRIX_MAX_VALS,
> +	/* Add new property size here */
> +};

As with the property names, I'm not sure whether having an array here
gives us much clarity.  I think it's fine to just pass
VLV_CSC_MATRIX_MAX_VALS directly to drm_property_create_blob() in the
code below.


> +
> +/* Default CSC values to create property with */
> +uint64_t vlv_csc_default[VLV_CSC_MATRIX_MAX_VALS] = {
> +	0x400, 0, 0, 0, 0x400, 0, 0, 0, 0x400
> +};
> +
> +/*
> +* vlv_set_csc
> +* Valleyview specific csc correction method.
> +* Programs the 6 csc registers with 3x3 correction matrix
> +* values.
> +* inputs:
> +* - intel_crtc*
> +* - color manager registered property for csc correction
> +* - data: pointer to correction values to be applied
> +*/
> +/* Enable color space conversion on PIPE */
> +bool vlv_set_csc(struct intel_crtc *intel_crtc,
> +	struct drm_property *prop, uint64_t values, bool enable)
> +{
> +	u32 count = 0;
> +	u32 c0, c1, c2;
> +	u32 pipeconf, csc_reg, data_size;
> +	uint64_t *blob_data;
> +	uint64_t *data = NULL;
> +	struct drm_device *dev = intel_crtc->base.dev;
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct drm_property_blob *blob = intel_crtc->csc_blob;
> +
> +	/* Sanity */
> +	if (!blob || (blob->length != VLV_CSC_MATRIX_MAX_VALS)) {
> +		DRM_ERROR("Invalid/NULL CSC blob\n");
> +		return false;
> +	}
> +	blob_data = (uint64_t *)blob->data;
> +
> +	/* No need of values to disable property */
> +	if (!enable)
> +		goto configure;
> +
> +	/* Enabling property needs correction values */
> +	data_size = VLV_CSC_MATRIX_MAX_VALS;
> +	data = kmalloc(sizeof(uint64_t) * (data_size), GFP_KERNEL);
> +	if (!data) {
> +		DRM_ERROR("Out of memory\n");
> +		return false;
> +	}
> +
> +	if (copy_from_user((void *)data, (const void __user *)values,
> +			data_size * sizeof(uint64_t))) {
> +		DRM_ERROR("Failed to copy all data\n");
> +		kfree(data);
> +		return false;
> +	}
> +
> +	DRM_DEBUG_DRIVER("Setting CSC on pipe = %d\n", intel_crtc->pipe);
> +	csc_reg = PIPECSC(intel_crtc->pipe);
> +
> +	/* Read CSC matrix, one row at a time */
> +	while (count < VLV_CSC_MATRIX_MAX_VALS) {
> +		c0 = data[count] & VLV_CSC_VALUE_MASK;
> +		*blob_data++ = c0;
> +		c1 = data[count] & VLV_CSC_VALUE_MASK;
> +		*blob_data++ = c1;
> +		c2 = data[count] & VLV_CSC_VALUE_MASK;
> +		*blob_data++ = c2;
> +
> +		/* C0 is LSB 12bits, C1 is MSB 16-27 */
> +		I915_WRITE(csc_reg, (c1 << VLV_CSC_COEFF_SHIFT) | c0);
> +		csc_reg += 4;
> +
> +		/* C2 is LSB 12 bits */
> +		I915_WRITE(csc_reg, c2);
> +		csc_reg += 4;
> +	}
> +
> +configure:
> +
> +	/* Enable / Disable csc correction */
> +	pipeconf = I915_READ(PIPECONF(intel_crtc->pipe));
> +	enable ? (pipeconf |= PIPECONF_CSC_ENABLE) :
> +		(pipeconf &= ~PIPECONF_CSC_ENABLE);
> +	I915_WRITE(PIPECONF(intel_crtc->pipe), pipeconf);
> +	POSTING_READ(PIPECONF(intel_crtc->pipe));
> +	DRM_DEBUG_DRIVER("CSC successfully %s pipe %C\n",
> +		enable ? "enabled" : "disabled", pipe_name(intel_crtc->pipe));
> +
> +	kfree(data);
> +	return true;
> +}
> +
> +bool intel_clrmgr_set_csc(struct drm_crtc *crtc,
> +	struct drm_property *prop, uint64_t values)
> +{
> +	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
> +	struct drm_device *dev = intel_crtc->base.dev;
> +	bool enable;
> +
> +	/* First value is enable/disable control, others are data */
> +	enable = *((uint64_t *)values);
> +	values += (sizeof(uint64_t));
> +
> +	if (IS_VALLEYVIEW(dev))
> +		return vlv_set_csc(intel_crtc, prop, values, enable);
> +
> +	/* Todo: Support other gen devices */
> +	DRM_ERROR("Color correction is supported only on VLV for now\n");
> +	return false;
> +}
> +
>  void
>  intel_attach_plane_color_correction(struct intel_plane *intel_plane)
>  {
> @@ -41,18 +173,92 @@ intel_attach_plane_color_correction(struct intel_plane *intel_plane)
>  void
>  intel_attach_pipe_color_correction(struct intel_crtc *intel_crtc)
>  {
> +	struct drm_device *dev = intel_crtc->base.dev;
> +	struct drm_mode_object *obj = &intel_crtc->base.base;
> +	struct drm_property *property = NULL;
> +
>  	DRM_DEBUG_DRIVER("\n");
> +	mutex_lock(&dev->mode_config.mutex);
> +
> +	/* color property = csc */
> +	property = dev->mode_config.csc_property;
> +	if (!property) {
> +		DRM_ERROR("No such property to attach\n");
> +		goto release_mutex;
> +	}
> +
> +	/* create blob for correction values */
> +	intel_crtc->csc_blob = drm_property_create_blob(dev,
> +		vlv_color_property_sizes[csc], (void *)vlv_csc_default);
> +	if (!intel_crtc->csc_blob) {
> +		DRM_ERROR("Failed to create property blob\n");
> +		goto release_mutex;
> +	}
> +
> +	/* Attach blob with property */
> +	if (drm_object_property_set_value(obj, property,
> +			intel_crtc->csc_blob->base.id)) {
> +		DRM_ERROR("Failed to attach property blob, destroying\n");
> +		drm_property_destroy_blob(dev, intel_crtc->csc_blob);
> +		goto release_mutex;
> +	}
> +
> +	DRM_DEBUG_DRIVER("Successfully attached CSC property\n");
> +
> +release_mutex:
> +	mutex_unlock(&dev->mode_config.mutex);
>  }
>  
>  int intel_clrmgr_create_color_properties(struct drm_device *dev)
>  {
> +	int ret = 0;
> +	struct drm_property *property;
> +
>  	DRM_DEBUG_DRIVER("\n");
> -	return 0;
> +	mutex_lock(&dev->mode_config.mutex);
> +
> +	/* CSC correction color property, blob type, size 0 */
> +	property = drm_property_create(dev, DRM_MODE_PROP_BLOB,
> +		clrmgr_property_names[csc], 0);
> +	if (!property) {
> +		DRM_ERROR("Failed to create property(CSC)\n");
> +		ret++;
> +	} else {
> +		dev->mode_config.csc_property = property;
> +		DRM_DEBUG_DRIVER("Created property: CSC\n");
> +	}
> +
> +	mutex_unlock(&dev->mode_config.mutex);
> +	return ret;
>  }
>  
>  void intel_clrmgr_destroy_color_properties(struct drm_device *dev)
>  {
> +	struct drm_crtc *crtc;
> +	struct intel_crtc *intel_crtc;
> +
>  	DRM_DEBUG_DRIVER("\n");
> +
> +	mutex_lock(&dev->mode_config.mutex);
> +
> +	/* CSC correction color property */
> +	if (dev->mode_config.csc_property) {
> +		drm_property_destroy(dev, dev->mode_config.csc_property);
> +		dev->mode_config.csc_property = NULL;
> +		DRM_DEBUG_DRIVER("Destroyed property: CSC\n");
> +	}
> +
> +	/* Destroy property blob from each CRTC */
> +	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
> +		intel_crtc = to_intel_crtc(crtc);
> +		if (intel_crtc->csc_blob) {
> +			drm_property_destroy_blob(dev, intel_crtc->csc_blob);
> +			intel_crtc->csc_blob = NULL;
> +		}
> +	}
> +
> +	mutex_unlock(&dev->mode_config.mutex);
> +	DRM_DEBUG_DRIVER("Successfully destroyed all color properties\n");
>  }
>  
>  void intel_clrmgr_init(struct drm_device *dev)
> diff --git a/drivers/gpu/drm/i915/intel_clrmgr.h b/drivers/gpu/drm/i915/intel_clrmgr.h
> index 8cff487..5725d6b 100644
> --- a/drivers/gpu/drm/i915/intel_clrmgr.h
> +++ b/drivers/gpu/drm/i915/intel_clrmgr.h
> @@ -39,6 +39,13 @@
>  #define CLRMGR_PROP_NAME_MAX				128
>  #define CLRMGR_PROP_RANGE_MAX				0xFFFFFFFFFFFFFFFF
>  
> +/* CSC */
> + /* CSC / Wide gamut */
> +#define VLV_CSC_MATRIX_MAX_VALS		9
> +#define VLV_CSC_VALUE_MASK			0xFFF
> +#define VLV_CSC_COEFF_SHIFT			16
> +
> +
>  /* Properties */
>  enum clrmgr_tweaks {
>  	csc = 0,
> @@ -50,6 +57,15 @@ enum clrmgr_tweaks {
>  };
>  
>  /*
> +* intel_clrmgr_set_csc
> +* CSC correction method is different across various
> +* gen devices. This wrapper function calls the respective
> +* platform specific function to set CSC
> +*/
> +bool intel_clrmgr_set_csc(struct drm_crtc *crtc,
> +	struct drm_property *prop, uint64_t data);
> +
> +/*
>  * intel_attach_plane_color_correction:
>  * Attach plane level color correction DRM properties to
>  * corresponding plane objects.
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 7ba5785..a10b9bb 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -437,6 +437,7 @@ struct intel_crtc {
>  
>  	int scanline_offset;
>  	struct intel_mmio_flip mmio_flip;
> +	struct drm_property_blob *csc_blob;
>  };
>  
>  struct intel_plane_wm_parameters {
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 31344bf..487ce44 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -851,6 +851,9 @@ struct drm_mode_config {
>  	struct drm_property *aspect_ratio_property;
>  	struct drm_property *dirty_info_property;
>  
> +	/* Color correction properties */
> +	struct drm_property *csc_property;
> +
>  	/* dumb ioctl parameters */
>  	uint32_t preferred_depth, prefer_shadow;
>  
> @@ -981,6 +984,10 @@ extern int drm_mode_connector_set_path_property(struct drm_connector *connector,
>  						char *path);
>  extern int drm_mode_connector_update_edid_property(struct drm_connector *connector,
>  						struct edid *edid);
> +extern struct drm_property_blob *drm_property_create_blob(struct drm_device *dev,
> +						int length, void *data);
> +extern void drm_property_destroy_blob(struct drm_device *dev,
> +			       struct drm_property_blob *blob);
>  
>  static inline bool drm_property_type_is(struct drm_property *property,
>  		uint32_t type)
> -- 
> 1.9.1
> 

-- 
Matt Roper
Graphics Software Engineer
IoTG Platform Enabling & Development
Intel Corporation
(916) 356-2795