Commit 0948c265 authored by Gajanan Bhat's avatar Gajanan Bhat Committed by Daniel Vetter
Browse files

drm/i915: Generalize drain latency computation 



Modify drain latency computation to use it for any plane. Same function can be
used for primary, cursor and sprite planes.

v2: Adressed review comments by Imre and Ville.
    - Moved clock round up in separate patch
    - Added WARN check for clock and pixel size
    - Simplified bit masking
    - Use cursor_base instead of reg read

v3: Changed to bitwise shorthand operator for plane_dl assignment.

Signed-off-by: default avatarGajanan Bhat <gajanan.bhat@intel.com>
Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent e2fcdaa9

drivers/gpu/drm/i915/i915_reg.h

+1 −0
Original line number Diff line number Diff line
@@ -4009,6 +4009,7 @@ enum punit_power_well { 
#define DDL_PLANE_PRECISION_64		(1<<7)

#define DDL_PLANE_PRECISION_32		(0<<7)

#define DDL_PLANE_SHIFT			0

#define DRAIN_LATENCY_MASK		0x7f



/* FIFO watermark sizes etc */

#define G4X_FIFO_LINE_SIZE	64

drivers/gpu/drm/i915/intel_pm.c

+50 −37
Original line number Diff line number Diff line
@@ -1271,33 +1271,24 @@ static bool g4x_compute_srwm(struct drm_device *dev, 
			      display, cursor);

}



static bool vlv_compute_drain_latency(struct drm_device *dev,

				     int plane,

				     int *plane_prec_mult,

				     int *plane_dl,

				     int *cursor_prec_mult,

				     int *cursor_dl)

static bool vlv_compute_drain_latency(struct drm_crtc *crtc,

				      int pixel_size,

				      int *prec_mult,

				      int *drain_latency)

{

	struct drm_crtc *crtc;

	int clock, pixel_size;

	int entries;

	int clock = to_intel_crtc(crtc)->config.adjusted_mode.crtc_clock;



	crtc = intel_get_crtc_for_plane(dev, plane);

	if (!intel_crtc_active(crtc))

	if (WARN(clock == 0, "Pixel clock is zero!\n"))

		return false;



	clock = to_intel_crtc(crtc)->config.adjusted_mode.crtc_clock;

	pixel_size = crtc->primary->fb->bits_per_pixel / 8;	/* BPP */

	if (WARN(pixel_size == 0, "Pixel size is zero!\n"))

		return false;



	entries = (clock / 1000) * pixel_size;

	*plane_prec_mult = (entries > 128) ?

		DRAIN_LATENCY_PRECISION_64 : DRAIN_LATENCY_PRECISION_32;

	*plane_dl = (64 * (*plane_prec_mult) * 4) / entries;



	entries = (clock / 1000) * 4;	/* BPP is always 4 for cursor */

	*cursor_prec_mult = (entries > 128) ?

		DRAIN_LATENCY_PRECISION_64 : DRAIN_LATENCY_PRECISION_32;

	*cursor_dl = (64 * (*cursor_prec_mult) * 4) / entries;

	*prec_mult = (entries > 128) ? DRAIN_LATENCY_PRECISION_64 :

				       DRAIN_LATENCY_PRECISION_32;

	*drain_latency = (64 * (*prec_mult) * 4) / entries;



	return true;

}
@@ -1312,24 +1303,46 @@ static bool vlv_compute_drain_latency(struct drm_device *dev, 


static void vlv_update_drain_latency(struct drm_crtc *crtc)

{

	struct drm_device *dev = crtc->dev;

	struct drm_i915_private *dev_priv = dev->dev_private;

	enum pipe pipe = to_intel_crtc(crtc)->pipe;

	int plane_prec, plane_dl;

	int cursor_prec, cursor_dl;

	int plane_prec_mult, cursor_prec_mult;



	if (vlv_compute_drain_latency(dev, pipe, &plane_prec_mult, &plane_dl,

				      &cursor_prec_mult, &cursor_dl)) {

		cursor_prec = (cursor_prec_mult == DRAIN_LATENCY_PRECISION_64) ?

			DDL_CURSOR_PRECISION_64 : DDL_CURSOR_PRECISION_32;

		plane_prec = (plane_prec_mult == DRAIN_LATENCY_PRECISION_64) ?

			DDL_PLANE_PRECISION_64 : DDL_PLANE_PRECISION_32;



		I915_WRITE(VLV_DDL(pipe), cursor_prec |

			   (cursor_dl << DDL_CURSOR_SHIFT) |

			   plane_prec | (plane_dl << DDL_PLANE_SHIFT));

	struct drm_i915_private *dev_priv = crtc->dev->dev_private;

	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);

	int pixel_size;

	int drain_latency;

	enum pipe pipe = intel_crtc->pipe;

	int plane_prec, prec_mult, plane_dl;



	plane_dl = I915_READ(VLV_DDL(pipe)) & ~(DDL_PLANE_PRECISION_64 |

		   DRAIN_LATENCY_MASK | DDL_CURSOR_PRECISION_64 |

		   (DRAIN_LATENCY_MASK << DDL_CURSOR_SHIFT));



	if (!intel_crtc_active(crtc)) {

		I915_WRITE(VLV_DDL(pipe), plane_dl);

		return;

	}



	/* Primary plane Drain Latency */

	pixel_size = crtc->primary->fb->bits_per_pixel / 8;	/* BPP */

	if (vlv_compute_drain_latency(crtc, pixel_size, &prec_mult, &drain_latency)) {

		plane_prec = (prec_mult == DRAIN_LATENCY_PRECISION_64) ?

					   DDL_PLANE_PRECISION_64 :

					   DDL_PLANE_PRECISION_32;

		plane_dl |= plane_prec | drain_latency;

	}



	/* Cursor Drain Latency

	 * BPP is always 4 for cursor

	 */

	pixel_size = 4;



	/* Program cursor DL only if it is enabled */

	if (intel_crtc->cursor_base &&

	    vlv_compute_drain_latency(crtc, pixel_size, &prec_mult, &drain_latency)) {

		plane_prec = (prec_mult == DRAIN_LATENCY_PRECISION_64) ?

					   DDL_CURSOR_PRECISION_64 :

					   DDL_CURSOR_PRECISION_32;

		plane_dl |= plane_prec | (drain_latency << DDL_CURSOR_SHIFT);

	}



	I915_WRITE(VLV_DDL(pipe), plane_dl);

}



#define single_plane_enabled(mask) is_power_of_2(mask)

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