1 files changed, 671 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_pipe_crc.c b/drivers/gpu/drm/i915/display/intel_pipe_crc.c
new file mode 100644
index 000000000000..1e2c4307d05a
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_pipe_crc.c
@@ -0,0 +1,671 @@
+/*
+ * Copyright © 2013 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.
+ *
+ * Author: Damien Lespiau <damien.lespiau@intel.com>
+ *
+ */
+
+#include <linux/circ_buf.h>
+#include <linux/ctype.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#include "intel_atomic.h"
+#include "intel_drv.h"
+#include "intel_pipe_crc.h"
+
+static const char * const pipe_crc_sources[] = {
+	[INTEL_PIPE_CRC_SOURCE_NONE] = "none",
+	[INTEL_PIPE_CRC_SOURCE_PLANE1] = "plane1",
+	[INTEL_PIPE_CRC_SOURCE_PLANE2] = "plane2",
+	[INTEL_PIPE_CRC_SOURCE_PLANE3] = "plane3",
+	[INTEL_PIPE_CRC_SOURCE_PLANE4] = "plane4",
+	[INTEL_PIPE_CRC_SOURCE_PLANE5] = "plane5",
+	[INTEL_PIPE_CRC_SOURCE_PLANE6] = "plane6",
+	[INTEL_PIPE_CRC_SOURCE_PLANE7] = "plane7",
+	[INTEL_PIPE_CRC_SOURCE_PIPE] = "pipe",
+	[INTEL_PIPE_CRC_SOURCE_TV] = "TV",
+	[INTEL_PIPE_CRC_SOURCE_DP_B] = "DP-B",
+	[INTEL_PIPE_CRC_SOURCE_DP_C] = "DP-C",
+	[INTEL_PIPE_CRC_SOURCE_DP_D] = "DP-D",
+	[INTEL_PIPE_CRC_SOURCE_AUTO] = "auto",
+};
+
+static int i8xx_pipe_crc_ctl_reg(enum intel_pipe_crc_source *source,
+				 u32 *val)
+{
+	if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
+		*source = INTEL_PIPE_CRC_SOURCE_PIPE;
+
+	switch (*source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_INCLUDE_BORDER_I8XX;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		*val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int i9xx_pipe_crc_auto_source(struct drm_i915_private *dev_priv,
+				     enum pipe pipe,
+				     enum intel_pipe_crc_source *source)
+{
+	struct drm_device *dev = &dev_priv->drm;
+	struct intel_encoder *encoder;
+	struct intel_crtc *crtc;
+	struct intel_digital_port *dig_port;
+	int ret = 0;
+
+	*source = INTEL_PIPE_CRC_SOURCE_PIPE;
+
+	drm_modeset_lock_all(dev);
+	for_each_intel_encoder(dev, encoder) {
+		if (!encoder->base.crtc)
+			continue;
+
+		crtc = to_intel_crtc(encoder->base.crtc);
+
+		if (crtc->pipe != pipe)
+			continue;
+
+		switch (encoder->type) {
+		case INTEL_OUTPUT_TVOUT:
+			*source = INTEL_PIPE_CRC_SOURCE_TV;
+			break;
+		case INTEL_OUTPUT_DP:
+		case INTEL_OUTPUT_EDP:
+			dig_port = enc_to_dig_port(&encoder->base);
+			switch (dig_port->base.port) {
+			case PORT_B:
+				*source = INTEL_PIPE_CRC_SOURCE_DP_B;
+				break;
+			case PORT_C:
+				*source = INTEL_PIPE_CRC_SOURCE_DP_C;
+				break;
+			case PORT_D:
+				*source = INTEL_PIPE_CRC_SOURCE_DP_D;
+				break;
+			default:
+				WARN(1, "nonexisting DP port %c\n",
+				     port_name(dig_port->base.port));
+				break;
+			}
+			break;
+		default:
+			break;
+		}
+	}
+	drm_modeset_unlock_all(dev);
+
+	return ret;
+}
+
+static int vlv_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
+				enum pipe pipe,
+				enum intel_pipe_crc_source *source,
+				u32 *val)
+{
+	bool need_stable_symbols = false;
+
+	if (*source == INTEL_PIPE_CRC_SOURCE_AUTO) {
+		int ret = i9xx_pipe_crc_auto_source(dev_priv, pipe, source);
+		if (ret)
+			return ret;
+	}
+
+	switch (*source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PIPE_VLV;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_DP_B:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_B_VLV;
+		need_stable_symbols = true;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_DP_C:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_C_VLV;
+		need_stable_symbols = true;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_DP_D:
+		if (!IS_CHERRYVIEW(dev_priv))
+			return -EINVAL;
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DP_D_VLV;
+		need_stable_symbols = true;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		*val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/*
+	 * When the pipe CRC tap point is after the transcoders we need
+	 * to tweak symbol-level features to produce a deterministic series of
+	 * symbols for a given frame. We need to reset those features only once
+	 * a frame (instead of every nth symbol):
+	 *   - DC-balance: used to ensure a better clock recovery from the data
+	 *     link (SDVO)
+	 *   - DisplayPort scrambling: used for EMI reduction
+	 */
+	if (need_stable_symbols) {
+		u32 tmp = I915_READ(PORT_DFT2_G4X);
+
+		tmp |= DC_BALANCE_RESET_VLV;
+		switch (pipe) {
+		case PIPE_A:
+			tmp |= PIPE_A_SCRAMBLE_RESET;
+			break;
+		case PIPE_B:
+			tmp |= PIPE_B_SCRAMBLE_RESET;
+			break;
+		case PIPE_C:
+			tmp |= PIPE_C_SCRAMBLE_RESET;
+			break;
+		default:
+			return -EINVAL;
+		}
+		I915_WRITE(PORT_DFT2_G4X, tmp);
+	}
+
+	return 0;
+}
+
+static int i9xx_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
+				 enum pipe pipe,
+				 enum intel_pipe_crc_source *source,
+				 u32 *val)
+{
+	if (*source == INTEL_PIPE_CRC_SOURCE_AUTO) {
+		int ret = i9xx_pipe_crc_auto_source(dev_priv, pipe, source);
+		if (ret)
+			return ret;
+	}
+
+	switch (*source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PIPE_I9XX;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_TV:
+		if (!SUPPORTS_TV(dev_priv))
+			return -EINVAL;
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_TV_PRE;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		*val = 0;
+		break;
+	default:
+		/*
+		 * The DP CRC source doesn't work on g4x.
+		 * It can be made to work to some degree by selecting
+		 * the correct CRC source before the port is enabled,
+		 * and not touching the CRC source bits again until
+		 * the port is disabled. But even then the bits
+		 * eventually get stuck and a reboot is needed to get
+		 * working CRCs on the pipe again. Let's simply
+		 * refuse to use DP CRCs on g4x.
+		 */
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void vlv_undo_pipe_scramble_reset(struct drm_i915_private *dev_priv,
+					 enum pipe pipe)
+{
+	u32 tmp = I915_READ(PORT_DFT2_G4X);
+
+	switch (pipe) {
+	case PIPE_A:
+		tmp &= ~PIPE_A_SCRAMBLE_RESET;
+		break;
+	case PIPE_B:
+		tmp &= ~PIPE_B_SCRAMBLE_RESET;
+		break;
+	case PIPE_C:
+		tmp &= ~PIPE_C_SCRAMBLE_RESET;
+		break;
+	default:
+		return;
+	}
+	if (!(tmp & PIPE_SCRAMBLE_RESET_MASK))
+		tmp &= ~DC_BALANCE_RESET_VLV;
+	I915_WRITE(PORT_DFT2_G4X, tmp);
+}
+
+static int ilk_pipe_crc_ctl_reg(enum intel_pipe_crc_source *source,
+				u32 *val)
+{
+	if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
+		*source = INTEL_PIPE_CRC_SOURCE_PIPE;
+
+	switch (*source) {
+	case INTEL_PIPE_CRC_SOURCE_PLANE1:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PRIMARY_ILK;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE2:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_SPRITE_ILK;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PIPE_ILK;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		*val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void
+intel_crtc_crc_setup_workarounds(struct intel_crtc *crtc, bool enable)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	struct intel_crtc_state *pipe_config;
+	struct drm_atomic_state *state;
+	struct drm_modeset_acquire_ctx ctx;
+	int ret;
+
+	drm_modeset_acquire_init(&ctx, 0);
+
+	state = drm_atomic_state_alloc(&dev_priv->drm);
+	if (!state) {
+		ret = -ENOMEM;
+		goto unlock;
+	}
+
+	state->acquire_ctx = &ctx;
+
+retry:
+	pipe_config = intel_atomic_get_crtc_state(state, crtc);
+	if (IS_ERR(pipe_config)) {
+		ret = PTR_ERR(pipe_config);
+		goto put_state;
+	}
+
+	pipe_config->base.mode_changed = pipe_config->has_psr;
+	pipe_config->crc_enabled = enable;
+
+	if (IS_HASWELL(dev_priv) &&
+	    pipe_config->base.active && crtc->pipe == PIPE_A &&
+	    pipe_config->cpu_transcoder == TRANSCODER_EDP)
+		pipe_config->base.mode_changed = true;
+
+	ret = drm_atomic_commit(state);
+
+put_state:
+	if (ret == -EDEADLK) {
+		drm_atomic_state_clear(state);
+		drm_modeset_backoff(&ctx);
+		goto retry;
+	}
+
+	drm_atomic_state_put(state);
+unlock:
+	WARN(ret, "Toggling workaround to %i returns %i\n", enable, ret);
+	drm_modeset_drop_locks(&ctx);
+	drm_modeset_acquire_fini(&ctx);
+}
+
+static int ivb_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
+				enum pipe pipe,
+				enum intel_pipe_crc_source *source,
+				u32 *val)
+{
+	if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
+		*source = INTEL_PIPE_CRC_SOURCE_PIPE;
+
+	switch (*source) {
+	case INTEL_PIPE_CRC_SOURCE_PLANE1:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PRIMARY_IVB;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE2:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_SPRITE_IVB;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PF_IVB;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		*val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int skl_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
+				enum pipe pipe,
+				enum intel_pipe_crc_source *source,
+				u32 *val)
+{
+	if (*source == INTEL_PIPE_CRC_SOURCE_AUTO)
+		*source = INTEL_PIPE_CRC_SOURCE_PIPE;
+
+	switch (*source) {
+	case INTEL_PIPE_CRC_SOURCE_PLANE1:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_1_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE2:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_2_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE3:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_3_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE4:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_4_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE5:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_5_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE6:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_6_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PLANE7:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_PLANE_7_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+		*val = PIPE_CRC_ENABLE | PIPE_CRC_SOURCE_DMUX_SKL;
+		break;
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		*val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int get_new_crc_ctl_reg(struct drm_i915_private *dev_priv,
+			       enum pipe pipe,
+			       enum intel_pipe_crc_source *source, u32 *val)
+{
+	if (IS_GEN(dev_priv, 2))
+		return i8xx_pipe_crc_ctl_reg(source, val);
+	else if (INTEL_GEN(dev_priv) < 5)
+		return i9xx_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
+	else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
+		return vlv_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
+	else if (IS_GEN_RANGE(dev_priv, 5, 6))
+		return ilk_pipe_crc_ctl_reg(source, val);
+	else if (INTEL_GEN(dev_priv) < 9)
+		return ivb_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
+	else
+		return skl_pipe_crc_ctl_reg(dev_priv, pipe, source, val);
+}
+
+static int
+display_crc_ctl_parse_source(const char *buf, enum intel_pipe_crc_source *s)
+{
+	int i;
+
+	if (!buf) {
+		*s = INTEL_PIPE_CRC_SOURCE_NONE;
+		return 0;
+	}
+
+	i = match_string(pipe_crc_sources, ARRAY_SIZE(pipe_crc_sources), buf);
+	if (i < 0)
+		return i;
+
+	*s = i;
+	return 0;
+}
+
+void intel_display_crc_init(struct drm_i915_private *dev_priv)
+{
+	enum pipe pipe;
+
+	for_each_pipe(dev_priv, pipe) {
+		struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[pipe];
+
+		spin_lock_init(&pipe_crc->lock);
+	}
+}
+
+static int i8xx_crc_source_valid(struct drm_i915_private *dev_priv,
+				 const enum intel_pipe_crc_source source)
+{
+	switch (source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int i9xx_crc_source_valid(struct drm_i915_private *dev_priv,
+				 const enum intel_pipe_crc_source source)
+{
+	switch (source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+	case INTEL_PIPE_CRC_SOURCE_TV:
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int vlv_crc_source_valid(struct drm_i915_private *dev_priv,
+				const enum intel_pipe_crc_source source)
+{
+	switch (source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+	case INTEL_PIPE_CRC_SOURCE_DP_B:
+	case INTEL_PIPE_CRC_SOURCE_DP_C:
+	case INTEL_PIPE_CRC_SOURCE_DP_D:
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ilk_crc_source_valid(struct drm_i915_private *dev_priv,
+				const enum intel_pipe_crc_source source)
+{
+	switch (source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+	case INTEL_PIPE_CRC_SOURCE_PLANE1:
+	case INTEL_PIPE_CRC_SOURCE_PLANE2:
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ivb_crc_source_valid(struct drm_i915_private *dev_priv,
+				const enum intel_pipe_crc_source source)
+{
+	switch (source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+	case INTEL_PIPE_CRC_SOURCE_PLANE1:
+	case INTEL_PIPE_CRC_SOURCE_PLANE2:
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int skl_crc_source_valid(struct drm_i915_private *dev_priv,
+				const enum intel_pipe_crc_source source)
+{
+	switch (source) {
+	case INTEL_PIPE_CRC_SOURCE_PIPE:
+	case INTEL_PIPE_CRC_SOURCE_PLANE1:
+	case INTEL_PIPE_CRC_SOURCE_PLANE2:
+	case INTEL_PIPE_CRC_SOURCE_PLANE3:
+	case INTEL_PIPE_CRC_SOURCE_PLANE4:
+	case INTEL_PIPE_CRC_SOURCE_PLANE5:
+	case INTEL_PIPE_CRC_SOURCE_PLANE6:
+	case INTEL_PIPE_CRC_SOURCE_PLANE7:
+	case INTEL_PIPE_CRC_SOURCE_NONE:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int
+intel_is_valid_crc_source(struct drm_i915_private *dev_priv,
+			  const enum intel_pipe_crc_source source)
+{
+	if (IS_GEN(dev_priv, 2))
+		return i8xx_crc_source_valid(dev_priv, source);
+	else if (INTEL_GEN(dev_priv) < 5)
+		return i9xx_crc_source_valid(dev_priv, source);
+	else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
+		return vlv_crc_source_valid(dev_priv, source);
+	else if (IS_GEN_RANGE(dev_priv, 5, 6))
+		return ilk_crc_source_valid(dev_priv, source);
+	else if (INTEL_GEN(dev_priv) < 9)
+		return ivb_crc_source_valid(dev_priv, source);
+	else
+		return skl_crc_source_valid(dev_priv, source);
+}
+
+const char *const *intel_crtc_get_crc_sources(struct drm_crtc *crtc,
+					      size_t *count)
+{
+	*count = ARRAY_SIZE(pipe_crc_sources);
+	return pipe_crc_sources;
+}
+
+int intel_crtc_verify_crc_source(struct drm_crtc *crtc, const char *source_name,
+				 size_t *values_cnt)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->dev);
+	enum intel_pipe_crc_source source;
+
+	if (display_crc_ctl_parse_source(source_name, &source) < 0) {
+		DRM_DEBUG_DRIVER("unknown source %s\n", source_name);
+		return -EINVAL;
+	}
+
+	if (source == INTEL_PIPE_CRC_SOURCE_AUTO ||
+	    intel_is_valid_crc_source(dev_priv, source) == 0) {
+		*values_cnt = 5;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+int intel_crtc_set_crc_source(struct drm_crtc *crtc, const char *source_name)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->dev);
+	struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[crtc->index];
+	enum intel_display_power_domain power_domain;
+	enum intel_pipe_crc_source source;
+	intel_wakeref_t wakeref;
+	u32 val = 0; /* shut up gcc */
+	int ret = 0;
+	bool enable;
+
+	if (display_crc_ctl_parse_source(source_name, &source) < 0) {
+		DRM_DEBUG_DRIVER("unknown source %s\n", source_name);
+		return -EINVAL;
+	}
+
+	power_domain = POWER_DOMAIN_PIPE(crtc->index);
+	wakeref = intel_display_power_get_if_enabled(dev_priv, power_domain);
+	if (!wakeref) {
+		DRM_DEBUG_KMS("Trying to capture CRC while pipe is off\n");
+		return -EIO;
+	}
+
+	enable = source != INTEL_PIPE_CRC_SOURCE_NONE;
+	if (enable)
+		intel_crtc_crc_setup_workarounds(to_intel_crtc(crtc), true);
+
+	ret = get_new_crc_ctl_reg(dev_priv, crtc->index, &source, &val);
+	if (ret != 0)
+		goto out;
+
+	pipe_crc->source = source;
+	I915_WRITE(PIPE_CRC_CTL(crtc->index), val);
+	POSTING_READ(PIPE_CRC_CTL(crtc->index));
+
+	if (!source) {
+		if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
+			vlv_undo_pipe_scramble_reset(dev_priv, crtc->index);
+	}
+
+	pipe_crc->skipped = 0;
+
+out:
+	if (!enable)
+		intel_crtc_crc_setup_workarounds(to_intel_crtc(crtc), false);
+
+	intel_display_power_put(dev_priv, power_domain, wakeref);
+
+	return ret;
+}
+
+void intel_crtc_enable_pipe_crc(struct intel_crtc *intel_crtc)
+{
+	struct drm_crtc *crtc = &intel_crtc->base;
+	struct drm_i915_private *dev_priv = to_i915(crtc->dev);
+	struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[crtc->index];
+	u32 val = 0;
+
+	if (!crtc->crc.opened)
+		return;
+
+	if (get_new_crc_ctl_reg(dev_priv, crtc->index, &pipe_crc->source, &val) < 0)
+		return;
+
+	/* Don't need pipe_crc->lock here, IRQs are not generated. */
+	pipe_crc->skipped = 0;
+
+	I915_WRITE(PIPE_CRC_CTL(crtc->index), val);
+	POSTING_READ(PIPE_CRC_CTL(crtc->index));
+}
+
+void intel_crtc_disable_pipe_crc(struct intel_crtc *intel_crtc)
+{
+	struct drm_crtc *crtc = &intel_crtc->base;
+	struct drm_i915_private *dev_priv = to_i915(crtc->dev);
+	struct intel_pipe_crc *pipe_crc = &dev_priv->pipe_crc[crtc->index];
+
+	/* Swallow crc's until we stop generating them. */
+	spin_lock_irq(&pipe_crc->lock);
+	pipe_crc->skipped = INT_MIN;
+	spin_unlock_irq(&pipe_crc->lock);
+
+	I915_WRITE(PIPE_CRC_CTL(crtc->index), 0);
+	POSTING_READ(PIPE_CRC_CTL(crtc->index));
+	synchronize_irq(dev_priv->drm.irq);
+}