diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 50b2057..0407720 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -42,7 +42,8 @@ i915-y += i915_cmd_parser.o \
 
 # ancilliary microcontroller support
 i915-y += intel_uc_loader.o \
-	  intel_guc_loader.o
+	  intel_guc_loader.o \
+	  intel_guc_client.o
 
 # autogenerated null render state
 i915-y += intel_renderstate_gen6.o \
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 2411118..0d60119 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1850,6 +1850,11 @@ static inline struct drm_i915_private *dev_to_i915(struct device *dev)
 	return to_i915(dev_get_drvdata(dev));
 }
 
+static inline struct drm_i915_private *guc_to_i915(struct intel_guc *guc)
+{
+	return container_of(guc, struct drm_i915_private, guc);
+}
+
 /* Iterate over initialised rings */
 #define for_each_ring(ring__, dev_priv__, i__) \
 	for ((i__) = 0; (i__) < I915_NUM_RINGS; (i__)++) \
diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
index bf80f32..fd6f394 100644
--- a/drivers/gpu/drm/i915/intel_guc.h
+++ b/drivers/gpu/drm/i915/intel_guc.h
@@ -27,6 +27,25 @@
 #include "intel_guc_api.h"
 #include "intel_uc_loader.h"
 
+#define GUC_DB_SIZE	PAGE_SIZE
+#define GUC_WQ_SIZE	(PAGE_SIZE * 2)
+
+struct i915_guc_client {
+	struct drm_i915_gem_object *client_obj;
+	u32 priority;
+	off_t doorbell_offset;
+	off_t proc_desc_offset;
+	off_t wq_offset;
+	uint16_t doorbell_id;
+	uint32_t ctx_index;
+	uint32_t wq_size;
+};
+
+#define I915_MAX_DOORBELLS	256
+#define INVALID_DOORBELL_ID	I915_MAX_DOORBELLS
+
+#define INVALID_CTX_ID		(MAX_GUC_GPU_CONTEXTS+1)
+
 struct intel_guc {
 	/* Generic uC firmware management */
 	struct intel_uc_fw guc_fw;
@@ -35,7 +54,15 @@ struct intel_guc {
 	uint32_t fw_ver_major;
 	uint32_t fw_ver_minor;
 
+	spinlock_t host2guc_lock;
+
 	struct drm_i915_gem_object *ctx_pool_obj;
+
+	struct i915_guc_client *execbuf_client;
+
+	struct ida ctx_ids;
+	int db_cacheline;
+	DECLARE_BITMAP(doorbell_bitmap, I915_MAX_DOORBELLS);
 };
 
 #define GUC_STATUS		0xc000
@@ -100,6 +127,16 @@ struct intel_guc {
 				 GUC_ENABLE_READ_CACHE_FOR_SRAM_DATA | \
 				 GUC_ENABLE_READ_CACHE_FOR_WOPCM_DATA)
 
+#define HOST2GUC_INTERRUPT	0xc4c8
+#define   HOST2GUC_TRIGGER	(1<<0)
+
+#define DRBMISC1		0x1984
+#define   DOORBELL_ENABLE	(1<<0)
+
+#define GEN8_DRBREGL(x) (0x1000 + (x) * 8)
+#define   GEN8_DRB_VALID (1<<0)
+#define GEN8_DRBREGU(x) (0x1000 + (x) * 8 + 4)
+
 /* intel_guc_loader.c */
 extern int intel_guc_ucode_load(struct drm_device *dev, bool wait);
 extern void intel_guc_ucode_fini(struct drm_device *dev);
@@ -114,4 +151,13 @@ void guc_scheduler_fini(struct drm_device *dev);
 int guc_scheduler_enable(struct drm_device *dev);
 void guc_scheduler_disable(struct drm_device *dev);
 
+/* intel_guc_client.c */
+struct i915_guc_client*
+i915_guc_client_alloc(struct drm_device *dev, u32 priority);
+void i915_guc_client_free(struct drm_device *dev,
+			  struct i915_guc_client *client);
+int i915_guc_client_submit(struct i915_guc_client *client,
+			   struct intel_context *ctx,
+			   struct intel_engine_cs *ring);
+
 #endif
diff --git a/drivers/gpu/drm/i915/intel_guc_client.c b/drivers/gpu/drm/i915/intel_guc_client.c
new file mode 100644
index 0000000..7922427
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel_guc_client.c
@@ -0,0 +1,430 @@
+/*
+ * 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.
+ *
+ */
+#include <linux/firmware.h>
+#include "i915_drv.h"
+#include "intel_guc.h"
+
+/**
+ * DOC: GuC Client
+ *
+ * i915_guc_client:
+ * We use the term client to avoid confusion with contexts. A i915_guc_client is
+ * equivalent to GuC object guc_context_desc. This context descriptor is
+ * allocated from a pool of 1024 entries. Kernel driver will allocate doorbell
+ * and workqueue for it. Also the process descriptor (guc_process_desc), which
+ * is mapped to client space. So the client can write Work Item then ring the
+ * doorbell.
+ *
+ * To simplify the implementation, we allocate one gem object that contains all
+ * pages for doorbell, process descriptor and workqueue.
+ *
+ * The Scratch registers:
+ * There are 16 MMIO-based registers start from 0xC180. The kernel driver writes
+ * a value to the action register (SOFT_SCRATCH_0) along with any data. It then
+ * triggers an interrupt on the GuC via another register write (0xC4C8).
+ * Firmware writes a success/fail code back to the action register after
+ * processes the request. The kernel driver polls waiting for this update and
+ * then proceeds.
+ * See intel_guc_action()
+ *
+ * Doorbells:
+ * Doorbells are interrupts to uKernel. A doorbell is a single cache line (QW)
+ * mapped into process space.
+ *
+ */
+
+/*
+ * Read GuC command/status register (SOFT_SCRATCH_0)
+ * Return true if it contains a response rather than a command
+ */
+static inline bool i915_guc_get_response(struct drm_i915_private *dev_priv,
+					 u32 *status)
+{
+	u32 val = I915_READ(SOFT_SCRATCH(0));
+	*status = val;
+	return GUC2HOST_IS_RESPONSE(val);
+}
+
+static int intel_guc_action(struct intel_guc *guc, u32 *data, u32 len)
+{
+	struct drm_i915_private *dev_priv = guc_to_i915(guc);
+	u32 status;
+	int i;
+	int ret;
+
+	if (WARN_ON(len < 1 || len > 15))
+		return -EINVAL;
+
+	spin_lock(&dev_priv->guc.host2guc_lock);
+
+	for (i = 0; i < len; i++)
+		I915_WRITE(SOFT_SCRATCH(i), data[i]);
+
+	POSTING_READ(SOFT_SCRATCH(i - 1));
+
+	I915_WRITE(HOST2GUC_INTERRUPT, HOST2GUC_TRIGGER);
+
+	ret = wait_for_atomic(i915_guc_get_response(dev_priv, &status), 10);
+	if (status != GUC2HOST_STATUS_SUCCESS) {
+		/* either GuC doesn't response, which is a TIMEOUT,
+		 * or a failure code is returned. */
+		if (ret != -ETIMEDOUT)
+			ret = -EIO;
+
+		DRM_ERROR("GUC: host2guc action 0x%X failed. ret=%d "
+				"status=0x%08X response=0x%08X\n",
+				data[0], ret, status,
+				I915_READ(SOFT_SCRATCH(15)));
+	}
+
+	spin_unlock(&dev_priv->guc.host2guc_lock);
+
+	return ret;
+}
+
+static void guc_release_doorbell(struct intel_guc *guc, uint16_t id)
+{
+	spin_lock(&guc->host2guc_lock);
+	bitmap_clear(guc->doorbell_bitmap, id, 1);
+	spin_unlock(&guc->host2guc_lock);
+}
+
+static uint16_t guc_assign_doorbell(struct intel_guc *guc, u32 priority)
+{
+	const uint16_t size = I915_MAX_DOORBELLS;
+	uint16_t id;
+
+	spin_lock(&guc->host2guc_lock);
+
+	/* The bitmap is split into two halves - high and normal priority. */
+	if (priority <= GUC_CTX_PRIORITY_HIGH) {
+		id = find_next_zero_bit(guc->doorbell_bitmap, size, size / 2);
+		if (id == size)
+			id = INVALID_DOORBELL_ID;
+	} else {
+		id = find_next_zero_bit(guc->doorbell_bitmap, size / 2, 0);
+		if (id == size / 2)
+			id = INVALID_DOORBELL_ID;
+	}
+
+	if (id != INVALID_DOORBELL_ID)
+		bitmap_set(guc->doorbell_bitmap, id, 1);
+
+	spin_unlock(&guc->host2guc_lock);
+
+	return id;
+}
+
+static off_t guc_select_doorbell_cacheline(struct intel_guc *guc)
+{
+	const int cacheline_size = boot_cpu_data.x86_clflush_size;
+	const int cacheline_per_page = PAGE_SIZE / cacheline_size;
+	off_t offset;
+
+	spin_lock(&guc->host2guc_lock);
+
+	/* Doorbell uses single cache line */
+	offset = cacheline_size * guc->db_cacheline;
+
+	/* Moving to next cache line to reduce contention */
+	guc->db_cacheline = (guc->db_cacheline + 1) % cacheline_per_page;
+
+	spin_unlock(&guc->host2guc_lock);
+
+	return offset;
+}
+
+static void init_ctx_desc(struct intel_guc *guc,
+			  struct i915_guc_client *client)
+{
+	struct guc_context_desc desc;
+	struct sg_table *sg;
+
+	memset(&desc, 0, sizeof(desc));
+
+	desc.attribute = GUC_CTX_DESC_ATTR_ACTIVE | GUC_CTX_DESC_ATTR_KERNEL;
+	desc.context_id = client->ctx_index;
+	desc.priority = client->priority;
+	desc.engines_used = (1 << RCS) | (1 << VCS) | (1 << BCS) |
+			    (1 << VECS) | (1 << VCS2); /* all engines */
+	desc.db_id = client->doorbell_id;
+
+	/*
+	 * The CPU address is only needed at certain points, so kmap_atomic on
+	 * demand instead of storing it in the ctx descriptor.
+	 * XXX: May make debug easier to have it mapped
+	 */
+	desc.db_trigger_cpu = 0;
+	desc.db_trigger_uk = client->doorbell_offset +
+		i915_gem_obj_ggtt_offset(client->client_obj);
+	desc.db_trigger_phy = client->doorbell_offset +
+		sg_dma_address(client->client_obj->pages->sgl);
+
+	desc.process_desc = client->proc_desc_offset +
+		i915_gem_obj_ggtt_offset(client->client_obj);
+
+	desc.wq_addr = client->wq_offset +
+		i915_gem_obj_ggtt_offset(client->client_obj);
+
+	desc.wq_size = client->wq_size;
+
+	/*
+	 * XXX: Take LRCs from an existing intel_context if this is not an
+	 * IsKMDCreatedContext client
+	 */
+	desc.desc_private = (uintptr_t)client;
+
+	/* Pool context is pinned already */
+	sg = guc->ctx_pool_obj->pages;
+	sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
+			     sizeof(desc) * client->ctx_index);
+}
+
+static void fini_ctx_desc(struct intel_guc *guc,
+			  struct i915_guc_client *client)
+{
+	struct guc_context_desc desc;
+	struct sg_table *sg;
+
+	memset(&desc, 0, sizeof(desc));
+
+	sg = guc->ctx_pool_obj->pages;
+	sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
+			     sizeof(desc) * client->ctx_index);
+}
+
+static void init_proc_desc(struct intel_guc *guc,
+			   struct i915_guc_client *client)
+{
+	struct guc_process_desc *desc;
+	void *base;
+
+	base = kmap_atomic(i915_gem_object_get_page(client->client_obj, 0));
+	desc = base + client->proc_desc_offset;
+
+	memset(desc, 0, sizeof(*desc));
+
+	/*
+	 * XXX: pDoorbell and WQVBaseAddress are pointers in process address
+	 * space for ring3 clients (set them as in mmap_ioctl) or kernel
+	 * space for kernel clients (map on demand instead? May make debug
+	 * easier to have it mapped).
+	 */
+	desc->wq_base_addr = 0;
+	desc->db_base_addr = 0;
+
+	desc->context_id = client->ctx_index;
+	desc->wq_size_bytes = client->wq_size;
+	desc->wq_status = WQ_STATUS_ACTIVE;
+	desc->priority = client->priority;
+
+	kunmap_atomic(base);
+}
+
+static int host2guc_allocate_doorbell(struct intel_guc *guc,
+				      struct i915_guc_client *client)
+{
+	u32 data[2];
+
+	data[0] = HOST2GUC_ACTION_ALLOCATE_DOORBELL;
+	data[1] = client->ctx_index;
+
+	return intel_guc_action(guc, data, 2);
+}
+
+static int host2guc_release_doorbell(struct intel_guc *guc,
+				     struct i915_guc_client *client)
+{
+	u32 data[2];
+
+	data[0] = HOST2GUC_ACTION_DEALLOCATE_DOORBELL;
+	data[1] = client->ctx_index;
+
+	return intel_guc_action(guc, data, 2);
+}
+
+static void init_doorbell(struct intel_guc *guc,
+			  struct i915_guc_client *client)
+{
+	struct guc_doorbell_info *doorbell;
+	void *base;
+
+	base = kmap_atomic(i915_gem_object_get_page(client->client_obj, 0));
+	doorbell = base + client->doorbell_offset;
+
+	doorbell->db_status = 1;
+	doorbell->cookie = 0;
+
+	kunmap_atomic(base);
+}
+
+static void disable_doorbell(struct intel_guc *guc,
+			     struct i915_guc_client *client)
+{
+	struct drm_i915_private *dev_priv = guc_to_i915(guc);
+	struct guc_doorbell_info *doorbell;
+	void *base;
+	int drbreg = GEN8_DRBREGL(client->doorbell_id);
+	int value;
+
+	base = kmap_atomic(i915_gem_object_get_page(client->client_obj, 0));
+	doorbell = base + client->doorbell_offset;
+
+	doorbell->db_status = 0;
+
+	kunmap_atomic(base);
+
+	I915_WRITE(drbreg, I915_READ(drbreg) & ~GEN8_DRB_VALID);
+
+	value = I915_READ(drbreg);
+	WARN_ON((value & GEN8_DRB_VALID) != 0);
+
+	I915_WRITE(GEN8_DRBREGU(client->doorbell_id), 0);
+	I915_WRITE(drbreg, 0);
+
+	/* XXX: wait for any interrupts */
+	/* XXX: wait for workqueue to drain */
+}
+
+void i915_guc_client_free(struct drm_device *dev,
+			  struct i915_guc_client *client)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_guc *guc = &dev_priv->guc;
+
+	if (!client)
+		return;
+
+	if (client->doorbell_id != INVALID_DOORBELL_ID) {
+		disable_doorbell(guc, client);
+		host2guc_release_doorbell(guc, client);
+		guc_release_doorbell(guc, client->doorbell_id);
+	}
+
+	/*
+	 * XXX: wait for any outstanding submissions before freeing memory.
+	 * Be sure to drop any locks
+	 */
+
+	intel_guc_release_gem_obj(client->client_obj);
+
+	if (client->ctx_index != INVALID_CTX_ID) {
+		fini_ctx_desc(guc, client);
+		ida_simple_remove(&guc->ctx_ids, client->ctx_index);
+	}
+
+	kfree(client);
+}
+
+/**
+ * i915_guc_client_alloc() - Allocate an i915_guc_client
+ * @dev:	drm device
+ * @priority:	four levels priority _CRITICAL, _HIGH, _NORMAL and _LOW
+ * 		The kernel client to replace ExecList submission is created with
+ * 		NORMAL priority. Priority of a client for scheduler can be HIGH,
+ * 		while a preemption context can use CRITICAL.
+ *
+ * Return:	An i915_guc_client object if success.
+ */
+struct i915_guc_client *
+i915_guc_client_alloc(struct drm_device *dev, u32 priority)
+{
+	struct i915_guc_client *client;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_guc *guc = &dev_priv->guc;
+	struct drm_i915_gem_object *obj;
+
+	client = kzalloc(sizeof(*client), GFP_KERNEL);
+	if (!client)
+		return NULL;
+
+	client->doorbell_id = INVALID_DOORBELL_ID;
+	client->priority = priority;
+
+	client->ctx_index = (uint32_t)ida_simple_get(&guc->ctx_ids, 0,
+			MAX_GUC_GPU_CONTEXTS, GFP_KERNEL);
+	if (client->ctx_index >= MAX_GUC_GPU_CONTEXTS) {
+		client->ctx_index = INVALID_CTX_ID;
+		goto err;
+	}
+
+	/* The first page is doorbell/proc_desc. Two followed pages are wq. */
+	obj = intel_guc_allocate_gem_obj(dev, GUC_DB_SIZE + GUC_WQ_SIZE);
+	if (!obj)
+		goto err;
+
+	client->client_obj = obj;
+	client->wq_offset = GUC_DB_SIZE;
+	client->wq_size = GUC_WQ_SIZE;
+
+	client->doorbell_offset = guc_select_doorbell_cacheline(guc);
+
+	/*
+	 * Since the doorbell only requires a single cacheline, we can save
+	 * space by putting the application process descriptor in the same
+	 * page. Use the half of the page that doesn't include the doorbell.
+	 */
+	if (client->doorbell_offset >= (GUC_DB_SIZE / 2))
+		client->proc_desc_offset = 0;
+	else
+		client->proc_desc_offset = (GUC_DB_SIZE / 2);
+
+	client->doorbell_id = guc_assign_doorbell(guc, client->priority);
+	if (client->doorbell_id == INVALID_DOORBELL_ID)
+		/* XXX: evict a doorbell instead */
+		goto err;
+
+	init_ctx_desc(guc, client);
+	init_proc_desc(guc, client);
+	init_doorbell(guc, client);
+
+	/* Invalidate GuC TLB to let GuC take the latest updates to GTT. */
+	I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
+
+	/* XXX: Any cache flushes needed? General domain mgmt calls? */
+
+	if (host2guc_allocate_doorbell(guc, client))
+		goto err;
+
+	return client;
+
+err:
+	i915_guc_client_free(dev, client);
+	return NULL;
+}
+
+/**
+ * i915_guc_client_submit() - Submit commands through GuC
+ * @client:	the guc client where commands will go through
+ * @ctx:	LRC where commands come from
+ * @ring:	HW engine that will excute the commands
+ *
+ * Return:	0 if succeed
+ */
+int i915_guc_client_submit(struct i915_guc_client *client,
+			   struct intel_context *ctx,
+			   struct intel_engine_cs *ring)
+{
+	return 0;
+}
diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c
index 5e021db..eb25cfb 100644
--- a/drivers/gpu/drm/i915/intel_guc_loader.c
+++ b/drivers/gpu/drm/i915/intel_guc_loader.c
@@ -292,12 +292,19 @@ static int guc_ucode_xfer(struct drm_device *dev)
 
 	/* Set MMIO/WA for GuC init */
 
+	I915_WRITE(DRBMISC1, DOORBELL_ENABLE);
+
 	/* Enable MIA caching. GuC clock gating is disabled. */
 	I915_WRITE(GUC_SHIM_CONTROL, GUC_SHIM_CONTROL_VALUE);
 
 	/* WaC6DisallowByGfxPause*/
 	I915_WRITE(GEN6_GFXPAUSE, 0x30FFF);
 
+	if (IS_SKYLAKE(dev))
+		I915_WRITE(GEN9_GT_PM_CONFIG, GEN8_GT_DOORBELL_ENABLE);
+	else
+		I915_WRITE(GEN8_GT_PM_CONFIG, GEN8_GT_DOORBELL_ENABLE);
+
 	if (IS_GEN9(dev)) {
 		/* DOP Clock Gating Enable for GuC clocks */
 		I915_WRITE(GEN7_MISCCPCTL, (GEN8_DOP_CLOCK_GATE_GUC_ENABLE |
diff --git a/drivers/gpu/drm/i915/intel_guc_scheduler.c b/drivers/gpu/drm/i915/intel_guc_scheduler.c
index 1047192..962443c 100644
--- a/drivers/gpu/drm/i915/intel_guc_scheduler.c
+++ b/drivers/gpu/drm/i915/intel_guc_scheduler.c
@@ -36,6 +36,8 @@ void guc_scheduler_fini(struct drm_device *dev)
 	if (ctx_pool) {
 		intel_guc_release_gem_obj(ctx_pool);
 		guc->ctx_pool_obj = NULL;
+
+		ida_destroy(&guc->ctx_ids);
 	}
 }
 
@@ -60,19 +62,42 @@ int guc_scheduler_init(struct drm_device *dev)
 	if (!guc->ctx_pool_obj)
 		return -ENOMEM;
 
+	spin_lock_init(&dev_priv->guc.host2guc_lock);
+
+	ida_init(&guc->ctx_ids);
+
+	memset(guc->doorbell_bitmap, 0, sizeof(guc->doorbell_bitmap));
+	guc->db_cacheline = 0;
+
 	return 0;
 }
 
 int guc_scheduler_enable(struct drm_device *dev)
 {
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_guc *guc = &dev_priv->guc;
+
 	if (!i915.enable_guc_scheduling)
 		return 0;
 
-	/* TODO: placeholder for guc scheduler enabling */
+	/* client for execbuf submission */
+	guc->execbuf_client =
+			i915_guc_client_alloc(dev, GUC_CTX_PRIORITY_NORMAL);
+	if (!guc->execbuf_client) {
+		DRM_ERROR("Failed to create execbuf guc_client\n");
+		return -ENOMEM;
+	}
+
 	return 0;
 }
 
 void guc_scheduler_disable(struct drm_device *dev)
 {
-	/* TODO: placeholder for guc scheduler disabling */
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_guc *guc = &dev_priv->guc;
+
+	if (guc->execbuf_client) {
+		i915_guc_client_free(dev, guc->execbuf_client);
+		guc->execbuf_client = NULL;
+	}
 }
