Subversion Repositories Kolibri OS

/*

 * Copyright © 2014 Intel Corporation

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the "Software"),

 * to deal in the Software without restriction, including without limitation

 * the rights to use, copy, modify, merge, publish, distribute, sublicense,

 * and/or sell copies of the Software, and to permit persons to whom the

 * Software is furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice (including the next

 * paragraph) shall be included in all copies or substantial portions of the

 * Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

 * IN THE SOFTWARE.

 *

 * Authors:

 *    Daniel Vetter 

 *

 */

#include "i915_drv.h"

#include "intel_drv.h"

/**

 * DOC: fifo underrun handling

 *

 * The i915 driver checks for display fifo underruns using the interrupt signals

 * provided by the hardware. This is enabled by default and fairly useful to

 * debug display issues, especially watermark settings.

 *

 * If an underrun is detected this is logged into dmesg. To avoid flooding logs

 * and occupying the cpu underrun interrupts are disabled after the first

 * occurrence until the next modeset on a given pipe.

 *

 * Note that underrun detection on gmch platforms is a bit more ugly since there

 * is no interrupt (despite that the signalling bit is in the PIPESTAT pipe

 * interrupt register). Also on some other platforms underrun interrupts are

 * shared, which means that if we detect an underrun we need to disable underrun

 * reporting on all pipes.

 *

 * The code also supports underrun detection on the PCH transcoder.

 */

static bool ivb_can_enable_err_int(struct drm_device *dev)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	struct intel_crtc *crtc;

	enum pipe pipe;

	assert_spin_locked(&dev_priv->irq_lock);

	for_each_pipe(dev_priv, pipe) {

		crtc = to_intel_crtc(dev_priv->pipe_to_crtc_mapping[pipe]);

		if (crtc->cpu_fifo_underrun_disabled)

			return false;

	}

	return true;

}

static bool cpt_can_enable_serr_int(struct drm_device *dev)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	enum pipe pipe;

	struct intel_crtc *crtc;

	assert_spin_locked(&dev_priv->irq_lock);

	for_each_pipe(dev_priv, pipe) {

		crtc = to_intel_crtc(dev_priv->pipe_to_crtc_mapping[pipe]);

		if (crtc->pch_fifo_underrun_disabled)

			return false;

	}

	return true;

}

/**

 * i9xx_check_fifo_underruns - check for fifo underruns

 * @dev_priv: i915 device instance

 *

 * This function checks for fifo underruns on GMCH platforms. This needs to be

 * done manually on modeset to make sure that we catch all underruns since they

 * do not generate an interrupt by themselves on these platforms.

 */

void i9xx_check_fifo_underruns(struct drm_i915_private *dev_priv)

{

	struct intel_crtc *crtc;

	spin_lock_irq(&dev_priv->irq_lock);

	for_each_intel_crtc(dev_priv->dev, crtc) {

		u32 reg = PIPESTAT(crtc->pipe);

		u32 pipestat;

		if (crtc->cpu_fifo_underrun_disabled)

			continue;

		pipestat = I915_READ(reg) & 0xffff0000;

		if ((pipestat & PIPE_FIFO_UNDERRUN_STATUS) == 0)

			continue;

		I915_WRITE(reg, pipestat | PIPE_FIFO_UNDERRUN_STATUS);

		POSTING_READ(reg);

		DRM_ERROR("pipe %c underrun\n", pipe_name(crtc->pipe));

	}

	spin_unlock_irq(&dev_priv->irq_lock);

}

static void i9xx_set_fifo_underrun_reporting(struct drm_device *dev,

					     enum pipe pipe,

					     bool enable, bool old)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	u32 reg = PIPESTAT(pipe);

	u32 pipestat = I915_READ(reg) & 0xffff0000;

	assert_spin_locked(&dev_priv->irq_lock);

	if (enable) {

		I915_WRITE(reg, pipestat | PIPE_FIFO_UNDERRUN_STATUS);

		POSTING_READ(reg);

	} else {

		if (old && pipestat & PIPE_FIFO_UNDERRUN_STATUS)

			DRM_ERROR("pipe %c underrun\n", pipe_name(pipe));

	}

}

static void ironlake_set_fifo_underrun_reporting(struct drm_device *dev,

						 enum pipe pipe, bool enable)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	uint32_t bit = (pipe == PIPE_A) ? DE_PIPEA_FIFO_UNDERRUN :

					  DE_PIPEB_FIFO_UNDERRUN;

	if (enable)

		ironlake_enable_display_irq(dev_priv, bit);

	else

		ironlake_disable_display_irq(dev_priv, bit);

}

static void ivybridge_set_fifo_underrun_reporting(struct drm_device *dev,

						  enum pipe pipe,

						  bool enable, bool old)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	if (enable) {

		I915_WRITE(GEN7_ERR_INT, ERR_INT_FIFO_UNDERRUN(pipe));

		if (!ivb_can_enable_err_int(dev))

			return;

		ironlake_enable_display_irq(dev_priv, DE_ERR_INT_IVB);

	} else {

		ironlake_disable_display_irq(dev_priv, DE_ERR_INT_IVB);

		if (old &&

		    I915_READ(GEN7_ERR_INT) & ERR_INT_FIFO_UNDERRUN(pipe)) {

			DRM_ERROR("uncleared fifo underrun on pipe %c\n",

				  pipe_name(pipe));

		}

	}

}

static void broadwell_set_fifo_underrun_reporting(struct drm_device *dev,

						  enum pipe pipe, bool enable)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	assert_spin_locked(&dev_priv->irq_lock);

	if (enable)

		dev_priv->de_irq_mask[pipe] &= ~GEN8_PIPE_FIFO_UNDERRUN;

	else

		dev_priv->de_irq_mask[pipe] |= GEN8_PIPE_FIFO_UNDERRUN;

	I915_WRITE(GEN8_DE_PIPE_IMR(pipe), dev_priv->de_irq_mask[pipe]);

	POSTING_READ(GEN8_DE_PIPE_IMR(pipe));

}

static void ibx_set_fifo_underrun_reporting(struct drm_device *dev,

					    enum transcoder pch_transcoder,

					    bool enable)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	uint32_t bit = (pch_transcoder == TRANSCODER_A) ?

		       SDE_TRANSA_FIFO_UNDER : SDE_TRANSB_FIFO_UNDER;

	if (enable)

		ibx_enable_display_interrupt(dev_priv, bit);

	else

		ibx_disable_display_interrupt(dev_priv, bit);

}

static void cpt_set_fifo_underrun_reporting(struct drm_device *dev,

					    enum transcoder pch_transcoder,

					    bool enable, bool old)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	if (enable) {

		I915_WRITE(SERR_INT,

			   SERR_INT_TRANS_FIFO_UNDERRUN(pch_transcoder));

		if (!cpt_can_enable_serr_int(dev))

			return;

		ibx_enable_display_interrupt(dev_priv, SDE_ERROR_CPT);

	} else {

		ibx_disable_display_interrupt(dev_priv, SDE_ERROR_CPT);

		if (old && I915_READ(SERR_INT) &

		    SERR_INT_TRANS_FIFO_UNDERRUN(pch_transcoder)) {

			DRM_ERROR("uncleared pch fifo underrun on pch transcoder %c\n",

				  transcoder_name(pch_transcoder));

		}

	}

}

static bool __intel_set_cpu_fifo_underrun_reporting(struct drm_device *dev,

						    enum pipe pipe, bool enable)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];

	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);

	bool old;

	assert_spin_locked(&dev_priv->irq_lock);

	old = !intel_crtc->cpu_fifo_underrun_disabled;

	intel_crtc->cpu_fifo_underrun_disabled = !enable;

	if (HAS_GMCH_DISPLAY(dev))

		i9xx_set_fifo_underrun_reporting(dev, pipe, enable, old);

	else if (IS_GEN5(dev) || IS_GEN6(dev))

		ironlake_set_fifo_underrun_reporting(dev, pipe, enable);

	else if (IS_GEN7(dev))

		ivybridge_set_fifo_underrun_reporting(dev, pipe, enable, old);

	else if (IS_GEN8(dev) || IS_GEN9(dev))

		broadwell_set_fifo_underrun_reporting(dev, pipe, enable);

	return old;

}

/**

 * intel_set_cpu_fifo_underrun_reporting - set cpu fifo underrrun reporting state

 * @dev_priv: i915 device instance

 * @pipe: (CPU) pipe to set state for

 * @enable: whether underruns should be reported or not

 *

 * This function sets the fifo underrun state for @pipe. It is used in the

 * modeset code to avoid false positives since on many platforms underruns are

 * expected when disabling or enabling the pipe.

 *

 * Notice that on some platforms disabling underrun reports for one pipe

 * disables for all due to shared interrupts. Actual reporting is still per-pipe

 * though.

 *

 * Returns the previous state of underrun reporting.

 */

bool intel_set_cpu_fifo_underrun_reporting(struct drm_i915_private *dev_priv,

					   enum pipe pipe, bool enable)

{

	unsigned long flags;

	bool ret;

	spin_lock_irqsave(&dev_priv->irq_lock, flags);

	ret = __intel_set_cpu_fifo_underrun_reporting(dev_priv->dev, pipe,

						      enable);

	spin_unlock_irqrestore(&dev_priv->irq_lock, flags);

	return ret;

}

/**

 * intel_set_pch_fifo_underrun_reporting - set PCH fifo underrun reporting state

 * @dev_priv: i915 device instance

 * @pch_transcoder: the PCH transcoder (same as pipe on IVB and older)

 * @enable: whether underruns should be reported or not

 *

 * This function makes us disable or enable PCH fifo underruns for a specific

 * PCH transcoder. Notice that on some PCHs (e.g. CPT/PPT), disabling FIFO

 * underrun reporting for one transcoder may also disable all the other PCH

 * error interruts for the other transcoders, due to the fact that there's just

 * one interrupt mask/enable bit for all the transcoders.

 *

 * Returns the previous state of underrun reporting.

 */

bool intel_set_pch_fifo_underrun_reporting(struct drm_i915_private *dev_priv,

					   enum transcoder pch_transcoder,

					   bool enable)

{

	struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pch_transcoder];

	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);

	unsigned long flags;

	bool old;

	/*

	 * NOTE: Pre-LPT has a fixed cpu pipe -> pch transcoder mapping, but LPT

	 * has only one pch transcoder A that all pipes can use. To avoid racy

	 * pch transcoder -> pipe lookups from interrupt code simply store the

	 * underrun statistics in crtc A. Since we never expose this anywhere

	 * nor use it outside of the fifo underrun code here using the "wrong"

	 * crtc on LPT won't cause issues.

	 */

	spin_lock_irqsave(&dev_priv->irq_lock, flags);

	old = !intel_crtc->pch_fifo_underrun_disabled;

	intel_crtc->pch_fifo_underrun_disabled = !enable;

	if (HAS_PCH_IBX(dev_priv->dev))

		ibx_set_fifo_underrun_reporting(dev_priv->dev, pch_transcoder,

						enable);

	else

		cpt_set_fifo_underrun_reporting(dev_priv->dev, pch_transcoder,

						enable, old);

	spin_unlock_irqrestore(&dev_priv->irq_lock, flags);

	return old;

}

/**

 * intel_cpu_fifo_underrun_irq_handler - handle CPU fifo underrun interrupt

 * @dev_priv: i915 device instance

 * @pipe: (CPU) pipe to set state for

 *

 * This handles a CPU fifo underrun interrupt, generating an underrun warning

 * into dmesg if underrun reporting is enabled and then disables the underrun

 * interrupt to avoid an irq storm.

 */

void intel_cpu_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv,

					 enum pipe pipe)

{

	struct drm_crtc *crtc = dev_priv->pipe_to_crtc_mapping[pipe];

	/* We may be called too early in init, thanks BIOS! */

	if (crtc == NULL)

		return;

	/* GMCH can't disable fifo underruns, filter them. */

	if (HAS_GMCH_DISPLAY(dev_priv->dev) &&

	    to_intel_crtc(crtc)->cpu_fifo_underrun_disabled)

		return;

	if (intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, false))

		DRM_ERROR("CPU pipe %c FIFO underrun\n",

			  pipe_name(pipe));

}

/**

 * intel_pch_fifo_underrun_irq_handler - handle PCH fifo underrun interrupt

 * @dev_priv: i915 device instance

 * @pch_transcoder: the PCH transcoder (same as pipe on IVB and older)

 *

 * This handles a PCH fifo underrun interrupt, generating an underrun warning

 * into dmesg if underrun reporting is enabled and then disables the underrun

 * interrupt to avoid an irq storm.

 */

void intel_pch_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv,

					 enum transcoder pch_transcoder)

{

	if (intel_set_pch_fifo_underrun_reporting(dev_priv, pch_transcoder,

						  false))

		DRM_ERROR("PCH transcoder %c FIFO underrun\n",

			  transcoder_name(pch_transcoder));

}