/* i915_drv.c -- i830,i845,i855,i865,i915 driver -*- linux-c -*-
 */
/*
 *
 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
 * All Rights Reserved.
 *
 * 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, sub license, 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 NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
 *
 */

#include <linux/device.h>
#include <linux/acpi.h>
#include <drm/drmP.h>
#include <drm/i915_drm.h>
#include "i915_drv.h"
#include "i915_trace.h"
#include "intel_drv.h"

#include <linux/console.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <drm/drm_crtc_helper.h>

static struct drm_driver driver;

#define GEN_DEFAULT_PIPEOFFSETS \
	.pipe_offsets = { PIPE_A_OFFSET, PIPE_B_OFFSET, \
			  PIPE_C_OFFSET, PIPE_EDP_OFFSET }, \
	.trans_offsets = { TRANSCODER_A_OFFSET, TRANSCODER_B_OFFSET, \
			   TRANSCODER_C_OFFSET, TRANSCODER_EDP_OFFSET }, \
	.palette_offsets = { PALETTE_A_OFFSET, PALETTE_B_OFFSET }

#define GEN_CHV_PIPEOFFSETS \
	.pipe_offsets = { PIPE_A_OFFSET, PIPE_B_OFFSET, \
			  CHV_PIPE_C_OFFSET }, \
	.trans_offsets = { TRANSCODER_A_OFFSET, TRANSCODER_B_OFFSET, \
			   CHV_TRANSCODER_C_OFFSET, }, \
	.palette_offsets = { PALETTE_A_OFFSET, PALETTE_B_OFFSET, \
			     CHV_PALETTE_C_OFFSET }

#define CURSOR_OFFSETS \
	.cursor_offsets = { CURSOR_A_OFFSET, CURSOR_B_OFFSET, CHV_CURSOR_C_OFFSET }

#define IVB_CURSOR_OFFSETS \
	.cursor_offsets = { CURSOR_A_OFFSET, IVB_CURSOR_B_OFFSET, IVB_CURSOR_C_OFFSET }

static const struct intel_device_info intel_i830_info = {
	.gen = 2, .is_mobile = 1, .cursor_needs_physical = 1, .num_pipes = 2,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_845g_info = {
	.gen = 2, .num_pipes = 1,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_i85x_info = {
	.gen = 2, .is_i85x = 1, .is_mobile = 1, .num_pipes = 2,
	.cursor_needs_physical = 1,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.has_fbc = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_i865g_info = {
	.gen = 2, .num_pipes = 1,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_i915g_info = {
	.gen = 3, .is_i915g = 1, .cursor_needs_physical = 1, .num_pipes = 2,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};
static const struct intel_device_info intel_i915gm_info = {
	.gen = 3, .is_mobile = 1, .num_pipes = 2,
	.cursor_needs_physical = 1,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.supports_tv = 1,
	.has_fbc = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};
static const struct intel_device_info intel_i945g_info = {
	.gen = 3, .has_hotplug = 1, .cursor_needs_physical = 1, .num_pipes = 2,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};
static const struct intel_device_info intel_i945gm_info = {
	.gen = 3, .is_i945gm = 1, .is_mobile = 1, .num_pipes = 2,
	.has_hotplug = 1, .cursor_needs_physical = 1,
	.has_overlay = 1, .overlay_needs_physical = 1,
	.supports_tv = 1,
	.has_fbc = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_i965g_info = {
	.gen = 4, .is_broadwater = 1, .num_pipes = 2,
	.has_hotplug = 1,
	.has_overlay = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_i965gm_info = {
	.gen = 4, .is_crestline = 1, .num_pipes = 2,
	.is_mobile = 1, .has_fbc = 1, .has_hotplug = 1,
	.has_overlay = 1,
	.supports_tv = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_g33_info = {
	.gen = 3, .is_g33 = 1, .num_pipes = 2,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.has_overlay = 1,
	.ring_mask = RENDER_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_g45_info = {
	.gen = 4, .is_g4x = 1, .need_gfx_hws = 1, .num_pipes = 2,
	.has_pipe_cxsr = 1, .has_hotplug = 1,
	.ring_mask = RENDER_RING | BSD_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_gm45_info = {
	.gen = 4, .is_g4x = 1, .num_pipes = 2,
	.is_mobile = 1, .need_gfx_hws = 1, .has_fbc = 1,
	.has_pipe_cxsr = 1, .has_hotplug = 1,
	.supports_tv = 1,
	.ring_mask = RENDER_RING | BSD_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_pineview_info = {
	.gen = 3, .is_g33 = 1, .is_pineview = 1, .is_mobile = 1, .num_pipes = 2,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.has_overlay = 1,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_ironlake_d_info = {
	.gen = 5, .num_pipes = 2,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.ring_mask = RENDER_RING | BSD_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_ironlake_m_info = {
	.gen = 5, .is_mobile = 1, .num_pipes = 2,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.has_fbc = 1,
	.ring_mask = RENDER_RING | BSD_RING,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_sandybridge_d_info = {
	.gen = 6, .num_pipes = 2,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.has_fbc = 1,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING,
	.has_llc = 1,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_sandybridge_m_info = {
	.gen = 6, .is_mobile = 1, .num_pipes = 2,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.has_fbc = 1,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING,
	.has_llc = 1,
	GEN_DEFAULT_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

#define GEN7_FEATURES  \
	.gen = 7, .num_pipes = 3, \
	.need_gfx_hws = 1, .has_hotplug = 1, \
	.has_fbc = 1, \
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING, \
	.has_llc = 1, \
	GEN_DEFAULT_PIPEOFFSETS, \
	IVB_CURSOR_OFFSETS

static const struct intel_device_info intel_ivybridge_d_info = {
	GEN7_FEATURES,
	.is_ivybridge = 1,
};

static const struct intel_device_info intel_ivybridge_m_info = {
	GEN7_FEATURES,
	.is_ivybridge = 1,
	.is_mobile = 1,
};

static const struct intel_device_info intel_ivybridge_q_info = {
	GEN7_FEATURES,
	.is_ivybridge = 1,
	.num_pipes = 0, /* legal, last one wins */
};

#define VLV_FEATURES  \
	.gen = 7, .num_pipes = 2, \
	.need_gfx_hws = 1, .has_hotplug = 1, \
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING, \
	.display_mmio_offset = VLV_DISPLAY_BASE, \
	GEN_DEFAULT_PIPEOFFSETS, \
	CURSOR_OFFSETS

static const struct intel_device_info intel_valleyview_m_info = {
	VLV_FEATURES,
	.is_valleyview = 1,
	.is_mobile = 1,
};

static const struct intel_device_info intel_valleyview_d_info = {
	VLV_FEATURES,
	.is_valleyview = 1,
};

#define HSW_FEATURES  \
	GEN7_FEATURES, \
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING, \
	.has_ddi = 1, \
	.has_fpga_dbg = 1

static const struct intel_device_info intel_haswell_d_info = {
	HSW_FEATURES,
	.is_haswell = 1,
};

static const struct intel_device_info intel_haswell_m_info = {
	HSW_FEATURES,
	.is_haswell = 1,
	.is_mobile = 1,
};

static const struct intel_device_info intel_broadwell_d_info = {
	HSW_FEATURES,
	.gen = 8,
};

static const struct intel_device_info intel_broadwell_m_info = {
	HSW_FEATURES,
	.gen = 8, .is_mobile = 1,
};

static const struct intel_device_info intel_broadwell_gt3d_info = {
	HSW_FEATURES,
	.gen = 8,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
};

static const struct intel_device_info intel_broadwell_gt3m_info = {
	HSW_FEATURES,
	.gen = 8, .is_mobile = 1,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
};

static const struct intel_device_info intel_cherryview_info = {
	.gen = 8, .num_pipes = 3,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING,
	.is_cherryview = 1,
	.display_mmio_offset = VLV_DISPLAY_BASE,
	GEN_CHV_PIPEOFFSETS,
	CURSOR_OFFSETS,
};

static const struct intel_device_info intel_skylake_info = {
	HSW_FEATURES,
	.is_skylake = 1,
	.gen = 9,
};

static const struct intel_device_info intel_skylake_gt3_info = {
	HSW_FEATURES,
	.is_skylake = 1,
	.gen = 9,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
};

static const struct intel_device_info intel_broxton_info = {
	.is_preliminary = 1,
	.is_broxton = 1,
	.gen = 9,
	.need_gfx_hws = 1, .has_hotplug = 1,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING,
	.num_pipes = 3,
	.has_ddi = 1,
	.has_fpga_dbg = 1,
	.has_fbc = 1,
	GEN_DEFAULT_PIPEOFFSETS,
	IVB_CURSOR_OFFSETS,
};

static const struct intel_device_info intel_kabylake_info = {
	HSW_FEATURES,
	.is_preliminary = 1,
	.is_kabylake = 1,
	.gen = 9,
};

static const struct intel_device_info intel_kabylake_gt3_info = {
	HSW_FEATURES,
	.is_preliminary = 1,
	.is_kabylake = 1,
	.gen = 9,
	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
};

/*
 * Make sure any device matches here are from most specific to most
 * general.  For example, since the Quanta match is based on the subsystem
 * and subvendor IDs, we need it to come before the more general IVB
 * PCI ID matches, otherwise we'll use the wrong info struct above.
 */
static const struct pci_device_id pciidlist[] = {
	INTEL_I830_IDS(&intel_i830_info),
	INTEL_I845G_IDS(&intel_845g_info),
	INTEL_I85X_IDS(&intel_i85x_info),
	INTEL_I865G_IDS(&intel_i865g_info),
	INTEL_I915G_IDS(&intel_i915g_info),
	INTEL_I915GM_IDS(&intel_i915gm_info),
	INTEL_I945G_IDS(&intel_i945g_info),
	INTEL_I945GM_IDS(&intel_i945gm_info),
	INTEL_I965G_IDS(&intel_i965g_info),
	INTEL_G33_IDS(&intel_g33_info),
	INTEL_I965GM_IDS(&intel_i965gm_info),
	INTEL_GM45_IDS(&intel_gm45_info),
	INTEL_G45_IDS(&intel_g45_info),
	INTEL_PINEVIEW_IDS(&intel_pineview_info),
	INTEL_IRONLAKE_D_IDS(&intel_ironlake_d_info),
	INTEL_IRONLAKE_M_IDS(&intel_ironlake_m_info),
	INTEL_SNB_D_IDS(&intel_sandybridge_d_info),
	INTEL_SNB_M_IDS(&intel_sandybridge_m_info),
	INTEL_IVB_Q_IDS(&intel_ivybridge_q_info), /* must be first IVB */
	INTEL_IVB_M_IDS(&intel_ivybridge_m_info),
	INTEL_IVB_D_IDS(&intel_ivybridge_d_info),
	INTEL_HSW_D_IDS(&intel_haswell_d_info),
	INTEL_HSW_M_IDS(&intel_haswell_m_info),
	INTEL_VLV_M_IDS(&intel_valleyview_m_info),
	INTEL_VLV_D_IDS(&intel_valleyview_d_info),
	INTEL_BDW_GT12M_IDS(&intel_broadwell_m_info),
	INTEL_BDW_GT12D_IDS(&intel_broadwell_d_info),
	INTEL_BDW_GT3M_IDS(&intel_broadwell_gt3m_info),
	INTEL_BDW_GT3D_IDS(&intel_broadwell_gt3d_info),
	INTEL_CHV_IDS(&intel_cherryview_info),
	INTEL_SKL_GT1_IDS(&intel_skylake_info),
	INTEL_SKL_GT2_IDS(&intel_skylake_info),
	INTEL_SKL_GT3_IDS(&intel_skylake_gt3_info),
	INTEL_SKL_GT4_IDS(&intel_skylake_gt3_info),
	INTEL_BXT_IDS(&intel_broxton_info),
	INTEL_KBL_GT1_IDS(&intel_kabylake_info),
	INTEL_KBL_GT2_IDS(&intel_kabylake_info),
	INTEL_KBL_GT3_IDS(&intel_kabylake_gt3_info),
	INTEL_KBL_GT4_IDS(&intel_kabylake_gt3_info),
	{0, 0, 0}
};

MODULE_DEVICE_TABLE(pci, pciidlist);

static enum intel_pch intel_virt_detect_pch(struct drm_device *dev)
{
	enum intel_pch ret = PCH_NOP;

	/*
	 * In a virtualized passthrough environment we can be in a
	 * setup where the ISA bridge is not able to be passed through.
	 * In this case, a south bridge can be emulated and we have to
	 * make an educated guess as to which PCH is really there.
	 */

	if (IS_GEN5(dev)) {
		ret = PCH_IBX;
		DRM_DEBUG_KMS("Assuming Ibex Peak PCH\n");
	} else if (IS_GEN6(dev) || IS_IVYBRIDGE(dev)) {
		ret = PCH_CPT;
		DRM_DEBUG_KMS("Assuming CouarPoint PCH\n");
	} else if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
		ret = PCH_LPT;
		DRM_DEBUG_KMS("Assuming LynxPoint PCH\n");
	} else if (IS_SKYLAKE(dev) || IS_KABYLAKE(dev)) {
		ret = PCH_SPT;
		DRM_DEBUG_KMS("Assuming SunrisePoint PCH\n");
	}

	return ret;
}

void intel_detect_pch(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct pci_dev *pch = NULL;

	/* In all current cases, num_pipes is equivalent to the PCH_NOP setting
	 * (which really amounts to a PCH but no South Display).
	 */
	if (INTEL_INFO(dev)->num_pipes == 0) {
		dev_priv->pch_type = PCH_NOP;
		return;
	}

	/*
	 * The reason to probe ISA bridge instead of Dev31:Fun0 is to
	 * make graphics device passthrough work easy for VMM, that only
	 * need to expose ISA bridge to let driver know the real hardware
	 * underneath. This is a requirement from virtualization team.
	 *
	 * In some virtualized environments (e.g. XEN), there is irrelevant
	 * ISA bridge in the system. To work reliably, we should scan trhough
	 * all the ISA bridge devices and check for the first match, instead
	 * of only checking the first one.
	 */
	while ((pch = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, pch))) {
		if (pch->vendor == PCI_VENDOR_ID_INTEL) {
			unsigned short id = pch->device & INTEL_PCH_DEVICE_ID_MASK;
			dev_priv->pch_id = id;

			if (id == INTEL_PCH_IBX_DEVICE_ID_TYPE) {
				dev_priv->pch_type = PCH_IBX;
				DRM_DEBUG_KMS("Found Ibex Peak PCH\n");
				WARN_ON(!IS_GEN5(dev));
			} else if (id == INTEL_PCH_CPT_DEVICE_ID_TYPE) {
				dev_priv->pch_type = PCH_CPT;
				DRM_DEBUG_KMS("Found CougarPoint PCH\n");
				WARN_ON(!(IS_GEN6(dev) || IS_IVYBRIDGE(dev)));
			} else if (id == INTEL_PCH_PPT_DEVICE_ID_TYPE) {
				/* PantherPoint is CPT compatible */
				dev_priv->pch_type = PCH_CPT;
				DRM_DEBUG_KMS("Found PantherPoint PCH\n");
				WARN_ON(!(IS_GEN6(dev) || IS_IVYBRIDGE(dev)));
			} else if (id == INTEL_PCH_LPT_DEVICE_ID_TYPE) {
				dev_priv->pch_type = PCH_LPT;
				DRM_DEBUG_KMS("Found LynxPoint PCH\n");
				WARN_ON(!IS_HASWELL(dev) && !IS_BROADWELL(dev));
				WARN_ON(IS_HSW_ULT(dev) || IS_BDW_ULT(dev));
			} else if (id == INTEL_PCH_LPT_LP_DEVICE_ID_TYPE) {
				dev_priv->pch_type = PCH_LPT;
				DRM_DEBUG_KMS("Found LynxPoint LP PCH\n");
				WARN_ON(!IS_HASWELL(dev) && !IS_BROADWELL(dev));
				WARN_ON(!IS_HSW_ULT(dev) && !IS_BDW_ULT(dev));
			} else if (id == INTEL_PCH_SPT_DEVICE_ID_TYPE) {
				dev_priv->pch_type = PCH_SPT;
				DRM_DEBUG_KMS("Found SunrisePoint PCH\n");
				WARN_ON(!IS_SKYLAKE(dev) &&
					!IS_KABYLAKE(dev));
			} else if (id == INTEL_PCH_SPT_LP_DEVICE_ID_TYPE) {
				dev_priv->pch_type = PCH_SPT;
				DRM_DEBUG_KMS("Found SunrisePoint LP PCH\n");
				WARN_ON(!IS_SKYLAKE(dev) &&
					!IS_KABYLAKE(dev));
			} else if ((id == INTEL_PCH_P2X_DEVICE_ID_TYPE) ||
				   ((id == INTEL_PCH_QEMU_DEVICE_ID_TYPE) &&
				    pch->subsystem_vendor == 0x1af4 &&
				    pch->subsystem_device == 0x1100)) {
				dev_priv->pch_type = intel_virt_detect_pch(dev);
			} else
				continue;

			break;
		}
	}
	if (!pch)
		DRM_DEBUG_KMS("No PCH found.\n");

	pci_dev_put(pch);
}

bool i915_semaphore_is_enabled(struct drm_device *dev)
{
	if (INTEL_INFO(dev)->gen < 6)
		return false;

	if (i915.semaphores >= 0)
		return i915.semaphores;

	/* TODO: make semaphores and Execlists play nicely together */
	if (i915.enable_execlists)
		return false;

	/* Until we get further testing... */
	if (IS_GEN8(dev))
		return false;

#ifdef CONFIG_INTEL_IOMMU
	/* Enable semaphores on SNB when IO remapping is off */
	if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped)
		return false;
#endif

	return true;
}

static void intel_suspend_encoders(struct drm_i915_private *dev_priv)
{
	struct drm_device *dev = dev_priv->dev;
	struct intel_encoder *encoder;

	drm_modeset_lock_all(dev);
	for_each_intel_encoder(dev, encoder)
		if (encoder->suspend)
			encoder->suspend(encoder);
	drm_modeset_unlock_all(dev);
}

static int intel_suspend_complete(struct drm_i915_private *dev_priv);
static int vlv_resume_prepare(struct drm_i915_private *dev_priv,
			      bool rpm_resume);
static int bxt_resume_prepare(struct drm_i915_private *dev_priv);

static bool suspend_to_idle(struct drm_i915_private *dev_priv)
{
#if IS_ENABLED(CONFIG_ACPI_SLEEP)
	if (acpi_target_system_state() < ACPI_STATE_S3)
		return true;
#endif
	return false;
}

static int i915_drm_suspend(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	pci_power_t opregion_target_state;
	int error;

	/* ignore lid events during suspend */
	mutex_lock(&dev_priv->modeset_restore_lock);
	dev_priv->modeset_restore = MODESET_SUSPENDED;
	mutex_unlock(&dev_priv->modeset_restore_lock);

	disable_rpm_wakeref_asserts(dev_priv);

	/* We do a lot of poking in a lot of registers, make sure they work
	 * properly. */
	intel_display_set_init_power(dev_priv, true);

	drm_kms_helper_poll_disable(dev);

	pci_save_state(dev->pdev);

	error = i915_gem_suspend(dev);
	if (error) {
		dev_err(&dev->pdev->dev,
			"GEM idle failed, resume might fail\n");
		goto out;
	}

	intel_guc_suspend(dev);

	intel_suspend_gt_powersave(dev);

	/*
	 * Disable CRTCs directly since we want to preserve sw state
	 * for _thaw. Also, power gate the CRTC power wells.
	 */
	drm_modeset_lock_all(dev);
	intel_display_suspend(dev);
	drm_modeset_unlock_all(dev);

	intel_dp_mst_suspend(dev);

	intel_runtime_pm_disable_interrupts(dev_priv);
	intel_hpd_cancel_work(dev_priv);

	intel_suspend_encoders(dev_priv);

	intel_suspend_hw(dev);

	i915_gem_suspend_gtt_mappings(dev);

	i915_save_state(dev);

	opregion_target_state = suspend_to_idle(dev_priv) ? PCI_D1 : PCI_D3cold;
	intel_opregion_notify_adapter(dev, opregion_target_state);

	intel_uncore_forcewake_reset(dev, false);
	intel_opregion_fini(dev);

	intel_fbdev_set_suspend(dev, FBINFO_STATE_SUSPENDED, true);

	dev_priv->suspend_count++;

	intel_display_set_init_power(dev_priv, false);

	if (HAS_CSR(dev_priv))
		flush_work(&dev_priv->csr.work);

out:
	enable_rpm_wakeref_asserts(dev_priv);

	return error;
}

static int i915_drm_suspend_late(struct drm_device *drm_dev, bool hibernation)
{
	struct drm_i915_private *dev_priv = drm_dev->dev_private;
	bool fw_csr;
	int ret;

	disable_rpm_wakeref_asserts(dev_priv);

	fw_csr = suspend_to_idle(dev_priv) && dev_priv->csr.dmc_payload;
	/*
	 * In case of firmware assisted context save/restore don't manually
	 * deinit the power domains. This also means the CSR/DMC firmware will
	 * stay active, it will power down any HW resources as required and
	 * also enable deeper system power states that would be blocked if the
	 * firmware was inactive.
	 */
	if (!fw_csr)
		intel_power_domains_suspend(dev_priv);

	ret = intel_suspend_complete(dev_priv);

	if (ret) {
		DRM_ERROR("Suspend complete failed: %d\n", ret);
		if (!fw_csr)
			intel_power_domains_init_hw(dev_priv, true);

		goto out;
	}

	pci_disable_device(drm_dev->pdev);
	/*
	 * During hibernation on some platforms the BIOS may try to access
	 * the device even though it's already in D3 and hang the machine. So
	 * leave the device in D0 on those platforms and hope the BIOS will
	 * power down the device properly. The issue was seen on multiple old
	 * GENs with different BIOS vendors, so having an explicit blacklist
	 * is inpractical; apply the workaround on everything pre GEN6. The
	 * platforms where the issue was seen:
	 * Lenovo Thinkpad X301, X61s, X60, T60, X41
	 * Fujitsu FSC S7110
	 * Acer Aspire 1830T
	 */
	if (!(hibernation && INTEL_INFO(dev_priv)->gen < 6))
		pci_set_power_state(drm_dev->pdev, PCI_D3hot);

	dev_priv->suspended_to_idle = suspend_to_idle(dev_priv);

out:
	enable_rpm_wakeref_asserts(dev_priv);

	return ret;
}

int i915_suspend_switcheroo(struct drm_device *dev, pm_message_t state)
{
	int error;

	if (!dev || !dev->dev_private) {
		DRM_ERROR("dev: %p\n", dev);
		DRM_ERROR("DRM not initialized, aborting suspend.\n");
		return -ENODEV;
	}

	if (WARN_ON_ONCE(state.event != PM_EVENT_SUSPEND &&
			 state.event != PM_EVENT_FREEZE))
		return -EINVAL;

	if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	error = i915_drm_suspend(dev);
	if (error)
		return error;

	return i915_drm_suspend_late(dev, false);
}

static int i915_drm_resume(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	disable_rpm_wakeref_asserts(dev_priv);

	mutex_lock(&dev->struct_mutex);
	i915_gem_restore_gtt_mappings(dev);
	mutex_unlock(&dev->struct_mutex);

	i915_restore_state(dev);
	intel_opregion_setup(dev);

	intel_init_pch_refclk(dev);
	drm_mode_config_reset(dev);

	/*
	 * Interrupts have to be enabled before any batches are run. If not the
	 * GPU will hang. i915_gem_init_hw() will initiate batches to
	 * update/restore the context.
	 *
	 * Modeset enabling in intel_modeset_init_hw() also needs working
	 * interrupts.
	 */
	intel_runtime_pm_enable_interrupts(dev_priv);

	mutex_lock(&dev->struct_mutex);
	if (i915_gem_init_hw(dev)) {
		DRM_ERROR("failed to re-initialize GPU, declaring wedged!\n");
			atomic_or(I915_WEDGED, &dev_priv->gpu_error.reset_counter);
	}
	mutex_unlock(&dev->struct_mutex);

	intel_guc_resume(dev);

	intel_modeset_init_hw(dev);

	spin_lock_irq(&dev_priv->irq_lock);
	if (dev_priv->display.hpd_irq_setup)
		dev_priv->display.hpd_irq_setup(dev);
	spin_unlock_irq(&dev_priv->irq_lock);

	drm_modeset_lock_all(dev);
	intel_display_resume(dev);
	drm_modeset_unlock_all(dev);

	intel_dp_mst_resume(dev);

	/*
	 * ... but also need to make sure that hotplug processing
	 * doesn't cause havoc. Like in the driver load code we don't
	 * bother with the tiny race here where we might loose hotplug
	 * notifications.
	 * */
	intel_hpd_init(dev_priv);
	/* Config may have changed between suspend and resume */
	drm_helper_hpd_irq_event(dev);

	intel_opregion_init(dev);

	intel_fbdev_set_suspend(dev, FBINFO_STATE_RUNNING, false);

	mutex_lock(&dev_priv->modeset_restore_lock);
	dev_priv->modeset_restore = MODESET_DONE;
	mutex_unlock(&dev_priv->modeset_restore_lock);

	intel_opregion_notify_adapter(dev, PCI_D0);

	drm_kms_helper_poll_enable(dev);

	enable_rpm_wakeref_asserts(dev_priv);

	return 0;
}

static int i915_drm_resume_early(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret = 0;

	/*
	 * We have a resume ordering issue with the snd-hda driver also
	 * requiring our device to be power up. Due to the lack of a
	 * parent/child relationship we currently solve this with an early
	 * resume hook.
	 *
	 * FIXME: This should be solved with a special hdmi sink device or
	 * similar so that power domains can be employed.
	 */
	if (pci_enable_device(dev->pdev)) {
		ret = -EIO;
		goto out;
	}

	pci_set_master(dev->pdev);

	disable_rpm_wakeref_asserts(dev_priv);

	if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
		ret = vlv_resume_prepare(dev_priv, false);
	if (ret)
		DRM_ERROR("Resume prepare failed: %d, continuing anyway\n",
			  ret);

	intel_uncore_early_sanitize(dev, true);

	if (IS_BROXTON(dev))
		ret = bxt_resume_prepare(dev_priv);
	else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
		hsw_disable_pc8(dev_priv);

	intel_uncore_sanitize(dev);

	if (!(dev_priv->suspended_to_idle && dev_priv->csr.dmc_payload))
		intel_power_domains_init_hw(dev_priv, true);

out:
	dev_priv->suspended_to_idle = false;

	enable_rpm_wakeref_asserts(dev_priv);

	return ret;
}

int i915_resume_switcheroo(struct drm_device *dev)
{
	int ret;

	if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	ret = i915_drm_resume_early(dev);
	if (ret)
		return ret;

	return i915_drm_resume(dev);
}

/**
 * i915_reset - reset chip after a hang
 * @dev: drm device to reset
 *
 * Reset the chip.  Useful if a hang is detected. Returns zero on successful
 * reset or otherwise an error code.
 *
 * Procedure is fairly simple:
 *   - reset the chip using the reset reg
 *   - re-init context state
 *   - re-init hardware status page
 *   - re-init ring buffer
 *   - re-init interrupt state
 *   - re-init display
 */
int i915_reset(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	bool simulated;
	int ret;

	intel_reset_gt_powersave(dev);

	mutex_lock(&dev->struct_mutex);

	i915_gem_reset(dev);

	simulated = dev_priv->gpu_error.stop_rings != 0;

	ret = intel_gpu_reset(dev);

	/* Also reset the gpu hangman. */
	if (simulated) {
		DRM_INFO("Simulated gpu hang, resetting stop_rings\n");
		dev_priv->gpu_error.stop_rings = 0;
		if (ret == -ENODEV) {
			DRM_INFO("Reset not implemented, but ignoring "
				 "error for simulated gpu hangs\n");
			ret = 0;
		}
	}

	if (i915_stop_ring_allow_warn(dev_priv))
		pr_notice("drm/i915: Resetting chip after gpu hang\n");

	if (ret) {
		DRM_ERROR("Failed to reset chip: %i\n", ret);
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	intel_overlay_reset(dev_priv);

	/* Ok, now get things going again... */

	/*
	 * Everything depends on having the GTT running, so we need to start
	 * there.  Fortunately we don't need to do this unless we reset the
	 * chip at a PCI level.
	 *
	 * Next we need to restore the context, but we don't use those
	 * yet either...
	 *
	 * Ring buffer needs to be re-initialized in the KMS case, or if X
	 * was running at the time of the reset (i.e. we weren't VT
	 * switched away).
	 */

	/* Used to prevent gem_check_wedged returning -EAGAIN during gpu reset */
	dev_priv->gpu_error.reload_in_reset = true;

	ret = i915_gem_init_hw(dev);

	dev_priv->gpu_error.reload_in_reset = false;

	mutex_unlock(&dev->struct_mutex);
	if (ret) {
		DRM_ERROR("Failed hw init on reset %d\n", ret);
		return ret;
	}

	/*
	 * rps/rc6 re-init is necessary to restore state lost after the
	 * reset and the re-install of gt irqs. Skip for ironlake per
	 * previous concerns that it doesn't respond well to some forms
	 * of re-init after reset.
	 */
	if (INTEL_INFO(dev)->gen > 5)
		intel_enable_gt_powersave(dev);

	return 0;
}

static int i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
	struct intel_device_info *intel_info =
		(struct intel_device_info *) ent->driver_data;

	if (IS_PRELIMINARY_HW(intel_info) && !i915.preliminary_hw_support) {
		DRM_INFO("This hardware requires preliminary hardware support.\n"
			 "See CONFIG_DRM_I915_PRELIMINARY_HW_SUPPORT, and/or modparam preliminary_hw_support\n");
		return -ENODEV;
	}

	/* Only bind to function 0 of the device. Early generations
	 * used function 1 as a placeholder for multi-head. This causes
	 * us confusion instead, especially on the systems where both
	 * functions have the same PCI-ID!
	 */
	if (PCI_FUNC(pdev->devfn))
		return -ENODEV;

	return drm_get_pci_dev(pdev, ent, &driver);
}

static void
i915_pci_remove(struct pci_dev *pdev)
{
	struct drm_device *dev = pci_get_drvdata(pdev);

	drm_put_dev(dev);
}

static int i915_pm_suspend(struct device *dev)
{
	struct pci_dev *pdev = to_pci_dev(dev);
	struct drm_device *drm_dev = pci_get_drvdata(pdev);

	if (!drm_dev || !drm_dev->dev_private) {
		dev_err(dev, "DRM not initialized, aborting suspend.\n");
		return -ENODEV;
	}

	if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	return i915_drm_suspend(drm_dev);
}

static int i915_pm_suspend_late(struct device *dev)
{
	struct drm_device *drm_dev = dev_to_i915(dev)->dev;

	/*
	 * We have a suspend ordering issue with the snd-hda driver also
	 * requiring our device to be power up. Due to the lack of a
	 * parent/child relationship we currently solve this with an late
	 * suspend hook.
	 *
	 * FIXME: This should be solved with a special hdmi sink device or
	 * similar so that power domains can be employed.
	 */
	if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	return i915_drm_suspend_late(drm_dev, false);
}

static int i915_pm_poweroff_late(struct device *dev)
{
	struct drm_device *drm_dev = dev_to_i915(dev)->dev;

	if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	return i915_drm_suspend_late(drm_dev, true);
}

static int i915_pm_resume_early(struct device *dev)
{
	struct drm_device *drm_dev = dev_to_i915(dev)->dev;

	if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	return i915_drm_resume_early(drm_dev);
}

static int i915_pm_resume(struct device *dev)
{
	struct drm_device *drm_dev = dev_to_i915(dev)->dev;

	if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF)
		return 0;

	return i915_drm_resume(drm_dev);
}

static int hsw_suspend_complete(struct drm_i915_private *dev_priv)
{
	hsw_enable_pc8(dev_priv);

	return 0;
}

static int bxt_suspend_complete(struct drm_i915_private *dev_priv)
{
	struct drm_device *dev = dev_priv->dev;

	/* TODO: when DC5 support is added disable DC5 here. */

	broxton_ddi_phy_uninit(dev);
	broxton_uninit_cdclk(dev);
	bxt_enable_dc9(dev_priv);

	return 0;
}

static int bxt_resume_prepare(struct drm_i915_private *dev_priv)
{
	struct drm_device *dev = dev_priv->dev;

	/* TODO: when CSR FW support is added make sure the FW is loaded */

	bxt_disable_dc9(dev_priv);

	/*
	 * TODO: when DC5 support is added enable DC5 here if the CSR FW
	 * is available.
	 */
	broxton_init_cdclk(dev);
	broxton_ddi_phy_init(dev);
	intel_prepare_ddi(dev);

	return 0;
}

/*
 * Save all Gunit registers that may be lost after a D3 and a subsequent
 * S0i[R123] transition. The list of registers needing a save/restore is
 * defined in the VLV2_S0IXRegs document. This documents marks all Gunit
 * registers in the following way:
 * - Driver: saved/restored by the driver
 * - Punit : saved/restored by the Punit firmware
 * - No, w/o marking: no need to save/restore, since the register is R/O or
 *                    used internally by the HW in a way that doesn't depend
 *                    keeping the content across a suspend/resume.
 * - Debug : used for debugging
 *
 * We save/restore all registers marked with 'Driver', with the following
 * exceptions:
 * - Registers out of use, including also registers marked with 'Debug'.
 *   These have no effect on the driver's operation, so we don't save/restore
 *   them to reduce the overhead.
 * - Registers that are fully setup by an initialization function called from
 *   the resume path. For example many clock gating and RPS/RC6 registers.
 * - Registers that provide the right functionality with their reset defaults.
 *
 * TODO: Except for registers that based on the above 3 criteria can be safely
 * ignored, we save/restore all others, practically treating the HW context as
 * a black-box for the driver. Further investigation is needed to reduce the
 * saved/restored registers even further, by following the same 3 criteria.
 */
static void vlv_save_gunit_s0ix_state(struct drm_i915_private *dev_priv)
{
	struct vlv_s0ix_state *s = &dev_priv->vlv_s0ix_state;
	int i;

	/* GAM 0x4000-0x4770 */
	s->wr_watermark		= I915_READ(GEN7_WR_WATERMARK);
	s->gfx_prio_ctrl	= I915_READ(GEN7_GFX_PRIO_CTRL);
	s->arb_mode		= I915_READ(ARB_MODE);
	s->gfx_pend_tlb0	= I915_READ(GEN7_GFX_PEND_TLB0);
	s->gfx_pend_tlb1	= I915_READ(GEN7_GFX_PEND_TLB1);

	for (i = 0; i < ARRAY_SIZE(s->lra_limits); i++)
		s->lra_limits[i] = I915_READ(GEN7_LRA_LIMITS(i));

	s->media_max_req_count	= I915_READ(GEN7_MEDIA_MAX_REQ_COUNT);
	s->gfx_max_req_count	= I915_READ(GEN7_GFX_MAX_REQ_COUNT);

	s->render_hwsp		= I915_READ(RENDER_HWS_PGA_GEN7);
	s->ecochk		= I915_READ(GAM_ECOCHK);
	s->bsd_hwsp		= I915_READ(BSD_HWS_PGA_GEN7);
	s->blt_hwsp		= I915_READ(BLT_HWS_PGA_GEN7);

	s->tlb_rd_addr		= I915_READ(GEN7_TLB_RD_ADDR);

	/* MBC 0x9024-0x91D0, 0x8500 */
	s->g3dctl		= I915_READ(VLV_G3DCTL);
	s->gsckgctl		= I915_READ(VLV_GSCKGCTL);
	s->mbctl		= I915_READ(GEN6_MBCTL);

	/* GCP 0x9400-0x9424, 0x8100-0x810C */
	s->ucgctl1		= I915_READ(GEN6_UCGCTL1);
	s->ucgctl3		= I915_READ(GEN6_UCGCTL3);
	s->rcgctl1		= I915_READ(GEN6_RCGCTL1);
	s->rcgctl2		= I915_READ(GEN6_RCGCTL2);
	s->rstctl		= I915_READ(GEN6_RSTCTL);
	s->misccpctl		= I915_READ(GEN7_MISCCPCTL);

	/* GPM 0xA000-0xAA84, 0x8000-0x80FC */
	s->gfxpause		= I915_READ(GEN6_GFXPAUSE);
	s->rpdeuhwtc		= I915_READ(GEN6_RPDEUHWTC);
	s->rpdeuc		= I915_READ(GEN6_RPDEUC);
	s->ecobus		= I915_READ(ECOBUS);
	s->pwrdwnupctl		= I915_READ(VLV_PWRDWNUPCTL);
	s->rp_down_timeout	= I915_READ(GEN6_RP_DOWN_TIMEOUT);
	s->rp_deucsw		= I915_READ(GEN6_RPDEUCSW);
	s->rcubmabdtmr		= I915_READ(GEN6_RCUBMABDTMR);
	s->rcedata		= I915_READ(VLV_RCEDATA);
	s->spare2gh		= I915_READ(VLV_SPAREG2H);

	/* Display CZ domain, 0x4400C-0x4402C, 0x4F000-0x4F11F */
	s->gt_imr		= I915_READ(GTIMR);
	s->gt_ier		= I915_READ(GTIER);
	s->pm_imr		= I915_READ(GEN6_PMIMR);
	s->pm_ier		= I915_READ(GEN6_PMIER);

	for (i = 0; i < ARRAY_SIZE(s->gt_scratch); i++)
		s->gt_scratch[i] = I915_READ(GEN7_GT_SCRATCH(i));

	/* GT SA CZ domain, 0x100000-0x138124 */
	s->tilectl		= I915_READ(TILECTL);
	s->gt_fifoctl		= I915_READ(GTFIFOCTL);
	s->gtlc_wake_ctrl	= I915_READ(VLV_GTLC_WAKE_CTRL);
	s->gtlc_survive		= I915_READ(VLV_GTLC_SURVIVABILITY_REG);
	s->pmwgicz		= I915_READ(VLV_PMWGICZ);

	/* Gunit-Display CZ domain, 0x182028-0x1821CF */
	s->gu_ctl0		= I915_READ(VLV_GU_CTL0);
	s->gu_ctl1		= I915_READ(VLV_GU_CTL1);
	s->pcbr			= I915_READ(VLV_PCBR);
	s->clock_gate_dis2	= I915_READ(VLV_GUNIT_CLOCK_GATE2);

	/*
	 * Not saving any of:
	 * DFT,		0x9800-0x9EC0
	 * SARB,	0xB000-0xB1FC
	 * GAC,		0x5208-0x524C, 0x14000-0x14C000
	 * PCI CFG
	 */
}

static void vlv_restore_gunit_s0ix_state(struct drm_i915_private *dev_priv)
{
	struct vlv_s0ix_state *s = &dev_priv->vlv_s0ix_state;
	u32 val;
	int i;

	/* GAM 0x4000-0x4770 */
	I915_WRITE(GEN7_WR_WATERMARK,	s->wr_watermark);
	I915_WRITE(GEN7_GFX_PRIO_CTRL,	s->gfx_prio_ctrl);
	I915_WRITE(ARB_MODE,		s->arb_mode | (0xffff << 16));
	I915_WRITE(GEN7_GFX_PEND_TLB0,	s->gfx_pend_tlb0);
	I915_WRITE(GEN7_GFX_PEND_TLB1,	s->gfx_pend_tlb1);

	for (i = 0; i < ARRAY_SIZE(s->lra_limits); i++)
		I915_WRITE(GEN7_LRA_LIMITS(i), s->lra_limits[i]);

	I915_WRITE(GEN7_MEDIA_MAX_REQ_COUNT, s->media_max_req_count);
	I915_WRITE(GEN7_GFX_MAX_REQ_COUNT, s->gfx_max_req_count);

	I915_WRITE(RENDER_HWS_PGA_GEN7,	s->render_hwsp);
	I915_WRITE(GAM_ECOCHK,		s->ecochk);
	I915_WRITE(BSD_HWS_PGA_GEN7,	s->bsd_hwsp);
	I915_WRITE(BLT_HWS_PGA_GEN7,	s->blt_hwsp);

	I915_WRITE(GEN7_TLB_RD_ADDR,	s->tlb_rd_addr);

	/* MBC 0x9024-0x91D0, 0x8500 */
	I915_WRITE(VLV_G3DCTL,		s->g3dctl);
	I915_WRITE(VLV_GSCKGCTL,	s->gsckgctl);
	I915_WRITE(GEN6_MBCTL,		s->mbctl);

	/* GCP 0x9400-0x9424, 0x8100-0x810C */
	I915_WRITE(GEN6_UCGCTL1,	s->ucgctl1);
	I915_WRITE(GEN6_UCGCTL3,	s->ucgctl3);
	I915_WRITE(GEN6_RCGCTL1,	s->rcgctl1);
	I915_WRITE(GEN6_RCGCTL2,	s->rcgctl2);
	I915_WRITE(GEN6_RSTCTL,		s->rstctl);
	I915_WRITE(GEN7_MISCCPCTL,	s->misccpctl);

	/* GPM 0xA000-0xAA84, 0x8000-0x80FC */
	I915_WRITE(GEN6_GFXPAUSE,	s->gfxpause);
	I915_WRITE(GEN6_RPDEUHWTC,	s->rpdeuhwtc);
	I915_WRITE(GEN6_RPDEUC,		s->rpdeuc);
	I915_WRITE(ECOBUS,		s->ecobus);
	I915_WRITE(VLV_PWRDWNUPCTL,	s->pwrdwnupctl);
	I915_WRITE(GEN6_RP_DOWN_TIMEOUT,s->rp_down_timeout);
	I915_WRITE(GEN6_RPDEUCSW,	s->rp_deucsw);
	I915_WRITE(GEN6_RCUBMABDTMR,	s->rcubmabdtmr);
	I915_WRITE(VLV_RCEDATA,		s->rcedata);
	I915_WRITE(VLV_SPAREG2H,	s->spare2gh);

	/* Display CZ domain, 0x4400C-0x4402C, 0x4F000-0x4F11F */
	I915_WRITE(GTIMR,		s->gt_imr);
	I915_WRITE(GTIER,		s->gt_ier);
	I915_WRITE(GEN6_PMIMR,		s->pm_imr);
	I915_WRITE(GEN6_PMIER,		s->pm_ier);

	for (i = 0; i < ARRAY_SIZE(s->gt_scratch); i++)
		I915_WRITE(GEN7_GT_SCRATCH(i), s->gt_scratch[i]);

	/* GT SA CZ domain, 0x100000-0x138124 */
	I915_WRITE(TILECTL,			s->tilectl);
	I915_WRITE(GTFIFOCTL,			s->gt_fifoctl);
	/*
	 * Preserve the GT allow wake and GFX force clock bit, they are not
	 * be restored, as they are used to control the s0ix suspend/resume
	 * sequence by the caller.
	 */
	val = I915_READ(VLV_GTLC_WAKE_CTRL);
	val &= VLV_GTLC_ALLOWWAKEREQ;
	val |= s->gtlc_wake_ctrl & ~VLV_GTLC_ALLOWWAKEREQ;
	I915_WRITE(VLV_GTLC_WAKE_CTRL, val);

	val = I915_READ(VLV_GTLC_SURVIVABILITY_REG);
	val &= VLV_GFX_CLK_FORCE_ON_BIT;
	val |= s->gtlc_survive & ~VLV_GFX_CLK_FORCE_ON_BIT;
	I915_WRITE(VLV_GTLC_SURVIVABILITY_REG, val);

	I915_WRITE(VLV_PMWGICZ,			s->pmwgicz);

	/* Gunit-Display CZ domain, 0x182028-0x1821CF */
	I915_WRITE(VLV_GU_CTL0,			s->gu_ctl0);
	I915_WRITE(VLV_GU_CTL1,			s->gu_ctl1);
	I915_WRITE(VLV_PCBR,			s->pcbr);
	I915_WRITE(VLV_GUNIT_CLOCK_GATE2,	s->clock_gate_dis2);
}

int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool force_on)
{
	u32 val;
	int err;

#define COND (I915_READ(VLV_GTLC_SURVIVABILITY_REG) & VLV_GFX_CLK_STATUS_BIT)

	val = I915_READ(VLV_GTLC_SURVIVABILITY_REG);
	val &= ~VLV_GFX_CLK_FORCE_ON_BIT;
	if (force_on)
		val |= VLV_GFX_CLK_FORCE_ON_BIT;
	I915_WRITE(VLV_GTLC_SURVIVABILITY_REG, val);

	if (!force_on)
		return 0;

	err = wait_for(COND, 20);
	if (err)
		DRM_ERROR("timeout waiting for GFX clock force-on (%08x)\n",
			  I915_READ(VLV_GTLC_SURVIVABILITY_REG));

	return err;
#undef COND
}

static int vlv_allow_gt_wake(struct drm_i915_private *dev_priv, bool allow)
{
	u32 val;
	int err = 0;

	val = I915_READ(VLV_GTLC_WAKE_CTRL);
	val &= ~VLV_GTLC_ALLOWWAKEREQ;
	if (allow)
		val |= VLV_GTLC_ALLOWWAKEREQ;
	I915_WRITE(VLV_GTLC_WAKE_CTRL, val);
	POSTING_READ(VLV_GTLC_WAKE_CTRL);

#define COND (!!(I915_READ(VLV_GTLC_PW_STATUS) & VLV_GTLC_ALLOWWAKEACK) == \
	      allow)
	err = wait_for(COND, 1);
	if (err)
		DRM_ERROR("timeout disabling GT waking\n");
	return err;
#undef COND
}

static int vlv_wait_for_gt_wells(struct drm_i915_private *dev_priv,
				 bool wait_for_on)
{
	u32 mask;
	u32 val;
	int err;

	mask = VLV_GTLC_PW_MEDIA_STATUS_MASK | VLV_GTLC_PW_RENDER_STATUS_MASK;
	val = wait_for_on ? mask : 0;
#define COND ((I915_READ(VLV_GTLC_PW_STATUS) & mask) == val)
	if (COND)
		return 0;

	DRM_DEBUG_KMS("waiting for GT wells to go %s (%08x)\n",
			wait_for_on ? "on" : "off",
			I915_READ(VLV_GTLC_PW_STATUS));

	/*
	 * RC6 transitioning can be delayed up to 2 msec (see
	 * valleyview_enable_rps), use 3 msec for safety.
	 */
	err = wait_for(COND, 3);
	if (err)
		DRM_ERROR("timeout waiting for GT wells to go %s\n",
			  wait_for_on ? "on" : "off");

	return err;
#undef COND
}

static void vlv_check_no_gt_access(struct drm_i915_private *dev_priv)
{
	if (!(I915_READ(VLV_GTLC_PW_STATUS) & VLV_GTLC_ALLOWWAKEERR))
		return;

	DRM_ERROR("GT register access while GT waking disabled\n");
	I915_WRITE(VLV_GTLC_PW_STATUS, VLV_GTLC_ALLOWWAKEERR);
}

static int vlv_suspend_complete(struct drm_i915_private *dev_priv)
{
	u32 mask;
	int err;

	/*
	 * Bspec defines the following GT well on flags as debug only, so
	 * don't treat them as hard failures.
	 */
	(void)vlv_wait_for_gt_wells(dev_priv, false);

	mask = VLV_GTLC_RENDER_CTX_EXISTS | VLV_GTLC_MEDIA_CTX_EXISTS;
	WARN_ON((I915_READ(VLV_GTLC_WAKE_CTRL) & mask) != mask);

	vlv_check_no_gt_access(dev_priv);

	err = vlv_force_gfx_clock(dev_priv, true);
	if (err)
		goto err1;

	err = vlv_allow_gt_wake(dev_priv, false);
	if (err)
		goto err2;

	if (!IS_CHERRYVIEW(dev_priv->dev))
		vlv_save_gunit_s0ix_state(dev_priv);

	err = vlv_force_gfx_clock(dev_priv, false);
	if (err)
		goto err2;

	return 0;

err2:
	/* For safety always re-enable waking and disable gfx clock forcing */
	vlv_allow_gt_wake(dev_priv, true);
err1:
	vlv_force_gfx_clock(dev_priv, false);

	return err;
}

static int vlv_resume_prepare(struct drm_i915_private *dev_priv,
				bool rpm_resume)
{
	struct drm_device *dev = dev_priv->dev;
	int err;
	int ret;

	/*
	 * If any of the steps fail just try to continue, that's the best we
	 * can do at this point. Return the first error code (which will also
	 * leave RPM permanently disabled).
	 */
	ret = vlv_force_gfx_clock(dev_priv, true);

	if (!IS_CHERRYVIEW(dev_priv->dev))
		vlv_restore_gunit_s0ix_state(dev_priv);

	err = vlv_allow_gt_wake(dev_priv, true);
	if (!ret)
		ret = err;

	err = vlv_force_gfx_clock(dev_priv, false);
	if (!ret)
		ret = err;

	vlv_check_no_gt_access(dev_priv);

	if (rpm_resume) {
		intel_init_clock_gating(dev);
		i915_gem_restore_fences(dev);
	}

	return ret;
}

static int intel_runtime_suspend(struct device *device)
{
	struct pci_dev *pdev = to_pci_dev(device);
	struct drm_device *dev = pci_get_drvdata(pdev);
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	if (WARN_ON_ONCE(!(dev_priv->rps.enabled && intel_enable_rc6(dev))))
		return -ENODEV;

	if (WARN_ON_ONCE(!HAS_RUNTIME_PM(dev)))
		return -ENODEV;

	DRM_DEBUG_KMS("Suspending device\n");

	/*
	 * We could deadlock here in case another thread holding struct_mutex
	 * calls RPM suspend concurrently, since the RPM suspend will wait
	 * first for this RPM suspend to finish. In this case the concurrent
	 * RPM resume will be followed by its RPM suspend counterpart. Still
	 * for consistency return -EAGAIN, which will reschedule this suspend.
	 */
	if (!mutex_trylock(&dev->struct_mutex)) {
		DRM_DEBUG_KMS("device lock contention, deffering suspend\n");
		/*
		 * Bump the expiration timestamp, otherwise the suspend won't
		 * be rescheduled.
		 */
		pm_runtime_mark_last_busy(device);

		return -EAGAIN;
	}

	disable_rpm_wakeref_asserts(dev_priv);

	/*
	 * We are safe here against re-faults, since the fault handler takes
	 * an RPM reference.
	 */
	i915_gem_release_all_mmaps(dev_priv);
	mutex_unlock(&dev->struct_mutex);

	cancel_delayed_work_sync(&dev_priv->gpu_error.hangcheck_work);

	intel_guc_suspend(dev);

	intel_suspend_gt_powersave(dev);
	intel_runtime_pm_disable_interrupts(dev_priv);

	ret = intel_suspend_complete(dev_priv);
	if (ret) {
		DRM_ERROR("Runtime suspend failed, disabling it (%d)\n", ret);
		intel_runtime_pm_enable_interrupts(dev_priv);

		enable_rpm_wakeref_asserts(dev_priv);

		return ret;
	}

	intel_uncore_forcewake_reset(dev, false);

	enable_rpm_wakeref_asserts(dev_priv);
	WARN_ON_ONCE(atomic_read(&dev_priv->pm.wakeref_count));
	dev_priv->pm.suspended = true;

	/*
	 * FIXME: We really should find a document that references the arguments
	 * used below!
	 */
	if (IS_BROADWELL(dev)) {
		/*
		 * On Broadwell, if we use PCI_D1 the PCH DDI ports will stop
		 * being detected, and the call we do at intel_runtime_resume()
		 * won't be able to restore them. Since PCI_D3hot matches the
		 * actual specification and appears to be working, use it.
		 */
		intel_opregion_notify_adapter(dev, PCI_D3hot);
	} else {
		/*
		 * current versions of firmware which depend on this opregion
		 * notification have repurposed the D1 definition to mean
		 * "runtime suspended" vs. what you would normally expect (D3)
		 * to distinguish it from notifications that might be sent via
		 * the suspend path.
		 */
		intel_opregion_notify_adapter(dev, PCI_D1);
	}

	assert_forcewakes_inactive(dev_priv);

	DRM_DEBUG_KMS("Device suspended\n");
	return 0;
}

static int intel_runtime_resume(struct device *device)
{
	struct pci_dev *pdev = to_pci_dev(device);
	struct drm_device *dev = pci_get_drvdata(pdev);
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret = 0;

	if (WARN_ON_ONCE(!HAS_RUNTIME_PM(dev)))
		return -ENODEV;

	DRM_DEBUG_KMS("Resuming device\n");

	WARN_ON_ONCE(atomic_read(&dev_priv->pm.wakeref_count));
	disable_rpm_wakeref_asserts(dev_priv);

	intel_opregion_notify_adapter(dev, PCI_D0);
	dev_priv->pm.suspended = false;

	intel_guc_resume(dev);

	if (IS_GEN6(dev_priv))
		intel_init_pch_refclk(dev);

	if (IS_BROXTON(dev))
		ret = bxt_resume_prepare(dev_priv);
	else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
		hsw_disable_pc8(dev_priv);
	else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
		ret = vlv_resume_prepare(dev_priv, true);

	/*
	 * No point of rolling back things in case of an error, as the best
	 * we can do is to hope that things will still work (and disable RPM).
	 */
	i915_gem_init_swizzling(dev);
	gen6_update_ring_freq(dev);

	intel_runtime_pm_enable_interrupts(dev_priv);

	/*
	 * On VLV/CHV display interrupts are part of the display
	 * power well, so hpd is reinitialized from there. For
	 * everyone else do it here.
	 */
	if (!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv))
		intel_hpd_init(dev_priv);

	intel_enable_gt_powersave(dev);

	enable_rpm_wakeref_asserts(dev_priv);

	if (ret)
		DRM_ERROR("Runtime resume failed, disabling it (%d)\n", ret);
	else
		DRM_DEBUG_KMS("Device resumed\n");

	return ret;
}

/*
 * This function implements common functionality of runtime and system
 * suspend sequence.
 */
static int intel_suspend_complete(struct drm_i915_private *dev_priv)
{
	int ret;

	if (IS_BROXTON(dev_priv))
		ret = bxt_suspend_complete(dev_priv);
	else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
		ret = hsw_suspend_complete(dev_priv);
	else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
		ret = vlv_suspend_complete(dev_priv);
	else
		ret = 0;

	return ret;
}

static const struct dev_pm_ops i915_pm_ops = {
	/*
	 * S0ix (via system suspend) and S3 event handlers [PMSG_SUSPEND,
	 * PMSG_RESUME]
	 */
	.suspend = i915_pm_suspend,
	.suspend_late = i915_pm_suspend_late,
	.resume_early = i915_pm_resume_early,
	.resume = i915_pm_resume,

	/*
	 * S4 event handlers
	 * @freeze, @freeze_late    : called (1) before creating the
	 *                            hibernation image [PMSG_FREEZE] and
	 *                            (2) after rebooting, before restoring
	 *                            the image [PMSG_QUIESCE]
	 * @thaw, @thaw_early       : called (1) after creating the hibernation
	 *                            image, before writing it [PMSG_THAW]
	 *                            and (2) after failing to create or
	 *                            restore the image [PMSG_RECOVER]
	 * @poweroff, @poweroff_late: called after writing the hibernation
	 *                            image, before rebooting [PMSG_HIBERNATE]
	 * @restore, @restore_early : called after rebooting and restoring the
	 *                            hibernation image [PMSG_RESTORE]
	 */
	.freeze = i915_pm_suspend,
	.freeze_late = i915_pm_suspend_late,
	.thaw_early = i915_pm_resume_early,
	.thaw = i915_pm_resume,
	.poweroff = i915_pm_suspend,
	.poweroff_late = i915_pm_poweroff_late,
	.restore_early = i915_pm_resume_early,
	.restore = i915_pm_resume,

	/* S0ix (via runtime suspend) event handlers */
	.runtime_suspend = intel_runtime_suspend,
	.runtime_resume = intel_runtime_resume,
};

static const struct vm_operations_struct i915_gem_vm_ops = {
	.fault = i915_gem_fault,
	.open = drm_gem_vm_open,
	.close = drm_gem_vm_close,
};

static const struct file_operations i915_driver_fops = {
	.owner = THIS_MODULE,
	.open = drm_open,
	.release = drm_release,
	.unlocked_ioctl = drm_ioctl,
	.mmap = drm_gem_mmap,
	.poll = drm_poll,
	.read = drm_read,
#ifdef CONFIG_COMPAT
	.compat_ioctl = i915_compat_ioctl,
#endif
	.llseek = noop_llseek,
};

static struct drm_driver driver = {
	/* Don't use MTRRs here; the Xserver or userspace app should
	 * deal with them for Intel hardware.
	 */
	.driver_features =
	    DRIVER_HAVE_IRQ | DRIVER_IRQ_SHARED | DRIVER_GEM | DRIVER_PRIME |
	    DRIVER_RENDER | DRIVER_MODESET,
	.load = i915_driver_load,
	.unload = i915_driver_unload,
	.open = i915_driver_open,
	.lastclose = i915_driver_lastclose,
	.preclose = i915_driver_preclose,
	.postclose = i915_driver_postclose,
	.set_busid = drm_pci_set_busid,

#if defined(CONFIG_DEBUG_FS)
	.debugfs_init = i915_debugfs_init,
	.debugfs_cleanup = i915_debugfs_cleanup,
#endif
	.gem_free_object = i915_gem_free_object,
	.gem_vm_ops = &i915_gem_vm_ops,

	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
	.gem_prime_export = i915_gem_prime_export,
	.gem_prime_import = i915_gem_prime_import,

	.dumb_create = i915_gem_dumb_create,
	.dumb_map_offset = i915_gem_mmap_gtt,
	.dumb_destroy = drm_gem_dumb_destroy,
	.ioctls = i915_ioctls,
	.fops = &i915_driver_fops,
	.name = DRIVER_NAME,
	.desc = DRIVER_DESC,
	.date = DRIVER_DATE,
	.major = DRIVER_MAJOR,
	.minor = DRIVER_MINOR,
	.patchlevel = DRIVER_PATCHLEVEL,
};

static struct pci_driver i915_pci_driver = {
	.name = DRIVER_NAME,
	.id_table = pciidlist,
	.probe = i915_pci_probe,
	.remove = i915_pci_remove,
	.driver.pm = &i915_pm_ops,
};

static int __init i915_init(void)
{
	driver.num_ioctls = i915_max_ioctl;

	/*
	 * Enable KMS by default, unless explicitly overriden by
	 * either the i915.modeset prarameter or by the
	 * vga_text_mode_force boot option.
	 */

	if (i915.modeset == 0)
		driver.driver_features &= ~DRIVER_MODESET;

#ifdef CONFIG_VGA_CONSOLE
	if (vgacon_text_force() && i915.modeset == -1)
		driver.driver_features &= ~DRIVER_MODESET;
#endif

	if (!(driver.driver_features & DRIVER_MODESET)) {
		/* Silently fail loading to not upset userspace. */
		DRM_DEBUG_DRIVER("KMS and UMS disabled.\n");
		return 0;
	}

	if (i915.nuclear_pageflip)
		driver.driver_features |= DRIVER_ATOMIC;

	return drm_pci_init(&driver, &i915_pci_driver);
}

static void __exit i915_exit(void)
{
	if (!(driver.driver_features & DRIVER_MODESET))
		return; /* Never loaded a driver. */

	drm_pci_exit(&driver, &i915_pci_driver);
}

module_init(i915_init);
module_exit(i915_exit);

MODULE_AUTHOR("Tungsten Graphics, Inc.");
MODULE_AUTHOR("Intel Corporation");

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL and additional rights");