intel_lrc.c 65.2 KB
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/*
 * 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:
 *    Ben Widawsky <ben@bwidawsk.net>
 *    Michel Thierry <michel.thierry@intel.com>
 *    Thomas Daniel <thomas.daniel@intel.com>
 *    Oscar Mateo <oscar.mateo@intel.com>
 *
 */

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/**
 * DOC: Logical Rings, Logical Ring Contexts and Execlists
 *
 * Motivation:
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 * GEN8 brings an expansion of the HW contexts: "Logical Ring Contexts".
 * These expanded contexts enable a number of new abilities, especially
 * "Execlists" (also implemented in this file).
 *
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 * One of the main differences with the legacy HW contexts is that logical
 * ring contexts incorporate many more things to the context's state, like
 * PDPs or ringbuffer control registers:
 *
 * The reason why PDPs are included in the context is straightforward: as
 * PPGTTs (per-process GTTs) are actually per-context, having the PDPs
 * contained there mean you don't need to do a ppgtt->switch_mm yourself,
 * instead, the GPU will do it for you on the context switch.
 *
 * But, what about the ringbuffer control registers (head, tail, etc..)?
 * shouldn't we just need a set of those per engine command streamer? This is
 * where the name "Logical Rings" starts to make sense: by virtualizing the
 * rings, the engine cs shifts to a new "ring buffer" with every context
 * switch. When you want to submit a workload to the GPU you: A) choose your
 * context, B) find its appropriate virtualized ring, C) write commands to it
 * and then, finally, D) tell the GPU to switch to that context.
 *
 * Instead of the legacy MI_SET_CONTEXT, the way you tell the GPU to switch
 * to a contexts is via a context execution list, ergo "Execlists".
 *
 * LRC implementation:
 * Regarding the creation of contexts, we have:
 *
 * - One global default context.
 * - One local default context for each opened fd.
 * - One local extra context for each context create ioctl call.
 *
 * Now that ringbuffers belong per-context (and not per-engine, like before)
 * and that contexts are uniquely tied to a given engine (and not reusable,
 * like before) we need:
 *
 * - One ringbuffer per-engine inside each context.
 * - One backing object per-engine inside each context.
 *
 * The global default context starts its life with these new objects fully
 * allocated and populated. The local default context for each opened fd is
 * more complex, because we don't know at creation time which engine is going
 * to use them. To handle this, we have implemented a deferred creation of LR
 * contexts:
 *
 * The local context starts its life as a hollow or blank holder, that only
 * gets populated for a given engine once we receive an execbuffer. If later
 * on we receive another execbuffer ioctl for the same context but a different
 * engine, we allocate/populate a new ringbuffer and context backing object and
 * so on.
 *
 * Finally, regarding local contexts created using the ioctl call: as they are
 * only allowed with the render ring, we can allocate & populate them right
 * away (no need to defer anything, at least for now).
 *
 * Execlists implementation:
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 * Execlists are the new method by which, on gen8+ hardware, workloads are
 * submitted for execution (as opposed to the legacy, ringbuffer-based, method).
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 * This method works as follows:
 *
 * When a request is committed, its commands (the BB start and any leading or
 * trailing commands, like the seqno breadcrumbs) are placed in the ringbuffer
 * for the appropriate context. The tail pointer in the hardware context is not
 * updated at this time, but instead, kept by the driver in the ringbuffer
 * structure. A structure representing this request is added to a request queue
 * for the appropriate engine: this structure contains a copy of the context's
 * tail after the request was written to the ring buffer and a pointer to the
 * context itself.
 *
 * If the engine's request queue was empty before the request was added, the
 * queue is processed immediately. Otherwise the queue will be processed during
 * a context switch interrupt. In any case, elements on the queue will get sent
 * (in pairs) to the GPU's ExecLists Submit Port (ELSP, for short) with a
 * globally unique 20-bits submission ID.
 *
 * When execution of a request completes, the GPU updates the context status
 * buffer with a context complete event and generates a context switch interrupt.
 * During the interrupt handling, the driver examines the events in the buffer:
 * for each context complete event, if the announced ID matches that on the head
 * of the request queue, then that request is retired and removed from the queue.
 *
 * After processing, if any requests were retired and the queue is not empty
 * then a new execution list can be submitted. The two requests at the front of
 * the queue are next to be submitted but since a context may not occur twice in
 * an execution list, if subsequent requests have the same ID as the first then
 * the two requests must be combined. This is done simply by discarding requests
 * at the head of the queue until either only one requests is left (in which case
 * we use a NULL second context) or the first two requests have unique IDs.
 *
 * By always executing the first two requests in the queue the driver ensures
 * that the GPU is kept as busy as possible. In the case where a single context
 * completes but a second context is still executing, the request for this second
 * context will be at the head of the queue when we remove the first one. This
 * request will then be resubmitted along with a new request for a different context,
 * which will cause the hardware to continue executing the second request and queue
 * the new request (the GPU detects the condition of a context getting preempted
 * with the same context and optimizes the context switch flow by not doing
 * preemption, but just sampling the new tail pointer).
 *
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 */

#include <drm/drmP.h>
#include <drm/i915_drm.h>
#include "i915_drv.h"
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#define GEN9_LR_CONTEXT_RENDER_SIZE (22 * PAGE_SIZE)
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#define GEN8_LR_CONTEXT_RENDER_SIZE (20 * PAGE_SIZE)
#define GEN8_LR_CONTEXT_OTHER_SIZE (2 * PAGE_SIZE)

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#define RING_EXECLIST_QFULL		(1 << 0x2)
#define RING_EXECLIST1_VALID		(1 << 0x3)
#define RING_EXECLIST0_VALID		(1 << 0x4)
#define RING_EXECLIST_ACTIVE_STATUS	(3 << 0xE)
#define RING_EXECLIST1_ACTIVE		(1 << 0x11)
#define RING_EXECLIST0_ACTIVE		(1 << 0x12)

#define GEN8_CTX_STATUS_IDLE_ACTIVE	(1 << 0)
#define GEN8_CTX_STATUS_PREEMPTED	(1 << 1)
#define GEN8_CTX_STATUS_ELEMENT_SWITCH	(1 << 2)
#define GEN8_CTX_STATUS_ACTIVE_IDLE	(1 << 3)
#define GEN8_CTX_STATUS_COMPLETE	(1 << 4)
#define GEN8_CTX_STATUS_LITE_RESTORE	(1 << 15)
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#define CTX_LRI_HEADER_0		0x01
#define CTX_CONTEXT_CONTROL		0x02
#define CTX_RING_HEAD			0x04
#define CTX_RING_TAIL			0x06
#define CTX_RING_BUFFER_START		0x08
#define CTX_RING_BUFFER_CONTROL		0x0a
#define CTX_BB_HEAD_U			0x0c
#define CTX_BB_HEAD_L			0x0e
#define CTX_BB_STATE			0x10
#define CTX_SECOND_BB_HEAD_U		0x12
#define CTX_SECOND_BB_HEAD_L		0x14
#define CTX_SECOND_BB_STATE		0x16
#define CTX_BB_PER_CTX_PTR		0x18
#define CTX_RCS_INDIRECT_CTX		0x1a
#define CTX_RCS_INDIRECT_CTX_OFFSET	0x1c
#define CTX_LRI_HEADER_1		0x21
#define CTX_CTX_TIMESTAMP		0x22
#define CTX_PDP3_UDW			0x24
#define CTX_PDP3_LDW			0x26
#define CTX_PDP2_UDW			0x28
#define CTX_PDP2_LDW			0x2a
#define CTX_PDP1_UDW			0x2c
#define CTX_PDP1_LDW			0x2e
#define CTX_PDP0_UDW			0x30
#define CTX_PDP0_LDW			0x32
#define CTX_LRI_HEADER_2		0x41
#define CTX_R_PWR_CLK_STATE		0x42
#define CTX_GPGPU_CSR_BASE_ADDRESS	0x44

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#define GEN8_CTX_VALID (1<<0)
#define GEN8_CTX_FORCE_PD_RESTORE (1<<1)
#define GEN8_CTX_FORCE_RESTORE (1<<2)
#define GEN8_CTX_L3LLC_COHERENT (1<<5)
#define GEN8_CTX_PRIVILEGE (1<<8)
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#define ASSIGN_CTX_PDP(ppgtt, reg_state, n) { \
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	const u64 _addr = test_bit(n, ppgtt->pdp.used_pdpes) ? \
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		ppgtt->pdp.page_directory[n]->daddr : \
		ppgtt->scratch_pd->daddr; \
	reg_state[CTX_PDP ## n ## _UDW+1] = upper_32_bits(_addr); \
	reg_state[CTX_PDP ## n ## _LDW+1] = lower_32_bits(_addr); \
}

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enum {
	ADVANCED_CONTEXT = 0,
	LEGACY_CONTEXT,
	ADVANCED_AD_CONTEXT,
	LEGACY_64B_CONTEXT
};
#define GEN8_CTX_MODE_SHIFT 3
enum {
	FAULT_AND_HANG = 0,
	FAULT_AND_HALT, /* Debug only */
	FAULT_AND_STREAM,
	FAULT_AND_CONTINUE /* Unsupported */
};
#define GEN8_CTX_ID_SHIFT 32
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#define CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT  0x17
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static int intel_lr_context_pin(struct intel_engine_cs *ring,
		struct intel_context *ctx);

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/**
 * intel_sanitize_enable_execlists() - sanitize i915.enable_execlists
 * @dev: DRM device.
 * @enable_execlists: value of i915.enable_execlists module parameter.
 *
 * Only certain platforms support Execlists (the prerequisites being
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 * support for Logical Ring Contexts and Aliasing PPGTT or better).
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 *
 * Return: 1 if Execlists is supported and has to be enabled.
 */
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int intel_sanitize_enable_execlists(struct drm_device *dev, int enable_execlists)
{
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	WARN_ON(i915.enable_ppgtt == -1);

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	if (INTEL_INFO(dev)->gen >= 9)
		return 1;

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	if (enable_execlists == 0)
		return 0;

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	if (HAS_LOGICAL_RING_CONTEXTS(dev) && USES_PPGTT(dev) &&
	    i915.use_mmio_flip >= 0)
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		return 1;

	return 0;
}
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/**
 * intel_execlists_ctx_id() - get the Execlists Context ID
 * @ctx_obj: Logical Ring Context backing object.
 *
 * Do not confuse with ctx->id! Unfortunately we have a name overload
 * here: the old context ID we pass to userspace as a handler so that
 * they can refer to a context, and the new context ID we pass to the
 * ELSP so that the GPU can inform us of the context status via
 * interrupts.
 *
 * Return: 20-bits globally unique context ID.
 */
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u32 intel_execlists_ctx_id(struct drm_i915_gem_object *ctx_obj)
{
	u32 lrca = i915_gem_obj_ggtt_offset(ctx_obj);

	/* LRCA is required to be 4K aligned so the more significant 20 bits
	 * are globally unique */
	return lrca >> 12;
}

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static uint64_t execlists_ctx_descriptor(struct intel_engine_cs *ring,
					 struct drm_i915_gem_object *ctx_obj)
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{
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	struct drm_device *dev = ring->dev;
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	uint64_t desc;
	uint64_t lrca = i915_gem_obj_ggtt_offset(ctx_obj);
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	WARN_ON(lrca & 0xFFFFFFFF00000FFFULL);
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	desc = GEN8_CTX_VALID;
	desc |= LEGACY_CONTEXT << GEN8_CTX_MODE_SHIFT;
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	if (IS_GEN8(ctx_obj->base.dev))
		desc |= GEN8_CTX_L3LLC_COHERENT;
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	desc |= GEN8_CTX_PRIVILEGE;
	desc |= lrca;
	desc |= (u64)intel_execlists_ctx_id(ctx_obj) << GEN8_CTX_ID_SHIFT;

	/* TODO: WaDisableLiteRestore when we start using semaphore
	 * signalling between Command Streamers */
	/* desc |= GEN8_CTX_FORCE_RESTORE; */

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	/* WaEnableForceRestoreInCtxtDescForVCS:skl */
	if (IS_GEN9(dev) &&
	    INTEL_REVID(dev) <= SKL_REVID_B0 &&
	    (ring->id == BCS || ring->id == VCS ||
	    ring->id == VECS || ring->id == VCS2))
		desc |= GEN8_CTX_FORCE_RESTORE;

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	return desc;
}

static void execlists_elsp_write(struct intel_engine_cs *ring,
				 struct drm_i915_gem_object *ctx_obj0,
				 struct drm_i915_gem_object *ctx_obj1)
{
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	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
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	uint64_t temp = 0;
	uint32_t desc[4];

	/* XXX: You must always write both descriptors in the order below. */
	if (ctx_obj1)
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		temp = execlists_ctx_descriptor(ring, ctx_obj1);
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	else
		temp = 0;
	desc[1] = (u32)(temp >> 32);
	desc[0] = (u32)temp;

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	temp = execlists_ctx_descriptor(ring, ctx_obj0);
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	desc[3] = (u32)(temp >> 32);
	desc[2] = (u32)temp;

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	spin_lock(&dev_priv->uncore.lock);
	intel_uncore_forcewake_get__locked(dev_priv, FORCEWAKE_ALL);
	I915_WRITE_FW(RING_ELSP(ring), desc[1]);
	I915_WRITE_FW(RING_ELSP(ring), desc[0]);
	I915_WRITE_FW(RING_ELSP(ring), desc[3]);
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	/* The context is automatically loaded after the following */
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	I915_WRITE_FW(RING_ELSP(ring), desc[2]);
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	/* ELSP is a wo register, so use another nearby reg for posting instead */
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	POSTING_READ_FW(RING_EXECLIST_STATUS(ring));
	intel_uncore_forcewake_put__locked(dev_priv, FORCEWAKE_ALL);
	spin_unlock(&dev_priv->uncore.lock);
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}

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static int execlists_update_context(struct drm_i915_gem_object *ctx_obj,
				    struct drm_i915_gem_object *ring_obj,
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				    struct i915_hw_ppgtt *ppgtt,
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				    u32 tail)
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{
	struct page *page;
	uint32_t *reg_state;

	page = i915_gem_object_get_page(ctx_obj, 1);
	reg_state = kmap_atomic(page);

	reg_state[CTX_RING_TAIL+1] = tail;
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	reg_state[CTX_RING_BUFFER_START+1] = i915_gem_obj_ggtt_offset(ring_obj);
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	/* True PPGTT with dynamic page allocation: update PDP registers and
	 * point the unallocated PDPs to the scratch page
	 */
	if (ppgtt) {
		ASSIGN_CTX_PDP(ppgtt, reg_state, 3);
		ASSIGN_CTX_PDP(ppgtt, reg_state, 2);
		ASSIGN_CTX_PDP(ppgtt, reg_state, 1);
		ASSIGN_CTX_PDP(ppgtt, reg_state, 0);
	}

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	kunmap_atomic(reg_state);

	return 0;
}

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static void execlists_submit_contexts(struct intel_engine_cs *ring,
				      struct intel_context *to0, u32 tail0,
				      struct intel_context *to1, u32 tail1)
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{
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	struct drm_i915_gem_object *ctx_obj0 = to0->engine[ring->id].state;
	struct intel_ringbuffer *ringbuf0 = to0->engine[ring->id].ringbuf;
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	struct drm_i915_gem_object *ctx_obj1 = NULL;
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	struct intel_ringbuffer *ringbuf1 = NULL;
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	BUG_ON(!ctx_obj0);
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	WARN_ON(!i915_gem_obj_is_pinned(ctx_obj0));
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	WARN_ON(!i915_gem_obj_is_pinned(ringbuf0->obj));
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	execlists_update_context(ctx_obj0, ringbuf0->obj, to0->ppgtt, tail0);
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	if (to1) {
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		ringbuf1 = to1->engine[ring->id].ringbuf;
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		ctx_obj1 = to1->engine[ring->id].state;
		BUG_ON(!ctx_obj1);
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		WARN_ON(!i915_gem_obj_is_pinned(ctx_obj1));
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		WARN_ON(!i915_gem_obj_is_pinned(ringbuf1->obj));
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		execlists_update_context(ctx_obj1, ringbuf1->obj, to1->ppgtt, tail1);
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	}

	execlists_elsp_write(ring, ctx_obj0, ctx_obj1);
}

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static void execlists_context_unqueue(struct intel_engine_cs *ring)
{
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	struct drm_i915_gem_request *req0 = NULL, *req1 = NULL;
	struct drm_i915_gem_request *cursor = NULL, *tmp = NULL;
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	assert_spin_locked(&ring->execlist_lock);
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	/*
	 * If irqs are not active generate a warning as batches that finish
	 * without the irqs may get lost and a GPU Hang may occur.
	 */
	WARN_ON(!intel_irqs_enabled(ring->dev->dev_private));

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	if (list_empty(&ring->execlist_queue))
		return;

	/* Try to read in pairs */
	list_for_each_entry_safe(cursor, tmp, &ring->execlist_queue,
				 execlist_link) {
		if (!req0) {
			req0 = cursor;
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		} else if (req0->ctx == cursor->ctx) {
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			/* Same ctx: ignore first request, as second request
			 * will update tail past first request's workload */
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			cursor->elsp_submitted = req0->elsp_submitted;
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			list_del(&req0->execlist_link);
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			list_add_tail(&req0->execlist_link,
				&ring->execlist_retired_req_list);
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			req0 = cursor;
		} else {
			req1 = cursor;
			break;
		}
	}

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	if (IS_GEN8(ring->dev) || IS_GEN9(ring->dev)) {
		/*
		 * WaIdleLiteRestore: make sure we never cause a lite
		 * restore with HEAD==TAIL
		 */
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		if (req0->elsp_submitted) {
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			/*
			 * Apply the wa NOOPS to prevent ring:HEAD == req:TAIL
			 * as we resubmit the request. See gen8_emit_request()
			 * for where we prepare the padding after the end of the
			 * request.
			 */
			struct intel_ringbuffer *ringbuf;

			ringbuf = req0->ctx->engine[ring->id].ringbuf;
			req0->tail += 8;
			req0->tail &= ringbuf->size - 1;
		}
	}

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	WARN_ON(req1 && req1->elsp_submitted);

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	execlists_submit_contexts(ring, req0->ctx, req0->tail,
				  req1 ? req1->ctx : NULL,
				  req1 ? req1->tail : 0);
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	req0->elsp_submitted++;
	if (req1)
		req1->elsp_submitted++;
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}

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static bool execlists_check_remove_request(struct intel_engine_cs *ring,
					   u32 request_id)
{
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	struct drm_i915_gem_request *head_req;
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	assert_spin_locked(&ring->execlist_lock);

	head_req = list_first_entry_or_null(&ring->execlist_queue,
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					    struct drm_i915_gem_request,
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					    execlist_link);

	if (head_req != NULL) {
		struct drm_i915_gem_object *ctx_obj =
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				head_req->ctx->engine[ring->id].state;
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		if (intel_execlists_ctx_id(ctx_obj) == request_id) {
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			WARN(head_req->elsp_submitted == 0,
			     "Never submitted head request\n");

			if (--head_req->elsp_submitted <= 0) {
				list_del(&head_req->execlist_link);
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				list_add_tail(&head_req->execlist_link,
					&ring->execlist_retired_req_list);
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				return true;
			}
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		}
	}

	return false;
}

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/**
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 * intel_lrc_irq_handler() - handle Context Switch interrupts
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 * @ring: Engine Command Streamer to handle.
 *
 * Check the unread Context Status Buffers and manage the submission of new
 * contexts to the ELSP accordingly.
 */
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void intel_lrc_irq_handler(struct intel_engine_cs *ring)
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{
	struct drm_i915_private *dev_priv = ring->dev->dev_private;
	u32 status_pointer;
	u8 read_pointer;
	u8 write_pointer;
	u32 status;
	u32 status_id;
	u32 submit_contexts = 0;

	status_pointer = I915_READ(RING_CONTEXT_STATUS_PTR(ring));

	read_pointer = ring->next_context_status_buffer;
	write_pointer = status_pointer & 0x07;
	if (read_pointer > write_pointer)
		write_pointer += 6;

	spin_lock(&ring->execlist_lock);

	while (read_pointer < write_pointer) {
		read_pointer++;
		status = I915_READ(RING_CONTEXT_STATUS_BUF(ring) +
				(read_pointer % 6) * 8);
		status_id = I915_READ(RING_CONTEXT_STATUS_BUF(ring) +
				(read_pointer % 6) * 8 + 4);

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		if (status & GEN8_CTX_STATUS_PREEMPTED) {
			if (status & GEN8_CTX_STATUS_LITE_RESTORE) {
				if (execlists_check_remove_request(ring, status_id))
					WARN(1, "Lite Restored request removed from queue\n");
			} else
				WARN(1, "Preemption without Lite Restore\n");
		}

		 if ((status & GEN8_CTX_STATUS_ACTIVE_IDLE) ||
		     (status & GEN8_CTX_STATUS_ELEMENT_SWITCH)) {
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			if (execlists_check_remove_request(ring, status_id))
				submit_contexts++;
		}
	}

	if (submit_contexts != 0)
		execlists_context_unqueue(ring);

	spin_unlock(&ring->execlist_lock);

	WARN(submit_contexts > 2, "More than two context complete events?\n");
	ring->next_context_status_buffer = write_pointer % 6;

	I915_WRITE(RING_CONTEXT_STATUS_PTR(ring),
		   ((u32)ring->next_context_status_buffer & 0x07) << 8);
}

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static int execlists_context_queue(struct intel_engine_cs *ring,
				   struct intel_context *to,
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				   u32 tail,
				   struct drm_i915_gem_request *request)
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{
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	struct drm_i915_gem_request *cursor;
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	int num_elements = 0;
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	if (to != ring->default_context)
		intel_lr_context_pin(ring, to);

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	if (!request) {
		/*
		 * If there isn't a request associated with this submission,
		 * create one as a temporary holder.
		 */
		request = kzalloc(sizeof(*request), GFP_KERNEL);
		if (request == NULL)
			return -ENOMEM;
		request->ring = ring;
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		request->ctx = to;
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		kref_init(&request->ref);
		i915_gem_context_reference(request->ctx);
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	} else {
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		i915_gem_request_reference(request);
572
		WARN_ON(to != request->ctx);
573
	}
574
	request->tail = tail;
575

576
	spin_lock_irq(&ring->execlist_lock);
577

578 579 580 581 582
	list_for_each_entry(cursor, &ring->execlist_queue, execlist_link)
		if (++num_elements > 2)
			break;

	if (num_elements > 2) {
583
		struct drm_i915_gem_request *tail_req;
584 585

		tail_req = list_last_entry(&ring->execlist_queue,
586
					   struct drm_i915_gem_request,
587 588
					   execlist_link);

589
		if (to == tail_req->ctx) {
590
			WARN(tail_req->elsp_submitted != 0,
591
				"More than 2 already-submitted reqs queued\n");
592
			list_del(&tail_req->execlist_link);
593 594
			list_add_tail(&tail_req->execlist_link,
				&ring->execlist_retired_req_list);
595 596 597
		}
	}

598
	list_add_tail(&request->execlist_link, &ring->execlist_queue);
599
	if (num_elements == 0)
600 601
		execlists_context_unqueue(ring);

602
	spin_unlock_irq(&ring->execlist_lock);
603 604 605 606

	return 0;
}

607 608
static int logical_ring_invalidate_all_caches(struct intel_ringbuffer *ringbuf,
					      struct intel_context *ctx)
609 610 611 612 613 614 615 616 617
{
	struct intel_engine_cs *ring = ringbuf->ring;
	uint32_t flush_domains;
	int ret;

	flush_domains = 0;
	if (ring->gpu_caches_dirty)
		flush_domains = I915_GEM_GPU_DOMAINS;

618 619
	ret = ring->emit_flush(ringbuf, ctx,
			       I915_GEM_GPU_DOMAINS, flush_domains);
620 621 622 623 624 625 626 627
	if (ret)
		return ret;

	ring->gpu_caches_dirty = false;
	return 0;
}

static int execlists_move_to_gpu(struct intel_ringbuffer *ringbuf,
628
				 struct intel_context *ctx,
629 630 631
				 struct list_head *vmas)
{
	struct intel_engine_cs *ring = ringbuf->ring;
632
	const unsigned other_rings = ~intel_ring_flag(ring);
633 634 635 636 637 638 639 640
	struct i915_vma *vma;
	uint32_t flush_domains = 0;
	bool flush_chipset = false;
	int ret;

	list_for_each_entry(vma, vmas, exec_list) {
		struct drm_i915_gem_object *obj = vma->obj;

641 642 643 644 645
		if (obj->active & other_rings) {
			ret = i915_gem_object_sync(obj, ring);
			if (ret)
				return ret;
		}
646 647 648 649 650 651 652 653 654 655 656 657 658

		if (obj->base.write_domain & I915_GEM_DOMAIN_CPU)
			flush_chipset |= i915_gem_clflush_object(obj, false);

		flush_domains |= obj->base.write_domain;
	}

	if (flush_domains & I915_GEM_DOMAIN_GTT)
		wmb();

	/* Unconditionally invalidate gpu caches and ensure that we do flush
	 * any residual writes from the previous batch.
	 */
659
	return logical_ring_invalidate_all_caches(ringbuf, ctx);
660 661
}

662 663
int intel_logical_ring_alloc_request_extras(struct drm_i915_gem_request *request,
					    struct intel_context *ctx)
664 665 666
{
	int ret;

667 668 669
	if (ctx != request->ring->default_context) {
		ret = intel_lr_context_pin(request->ring, ctx);
		if (ret)
670 671 672
			return ret;
	}

673 674
	request->ringbuf = ctx->engine[request->ring->id].ringbuf;
	request->ctx     = ctx;
675 676 677 678 679
	i915_gem_context_reference(request->ctx);

	return 0;
}

680 681 682
static int logical_ring_wait_for_space(struct intel_ringbuffer *ringbuf,
				       struct intel_context *ctx,
				       int bytes)
683 684 685
{
	struct intel_engine_cs *ring = ringbuf->ring;
	struct drm_i915_gem_request *request;
686 687
	unsigned space;
	int ret;
688 689 690 691 692 693 694 695 696 697

	if (intel_ring_space(ringbuf) >= bytes)
		return 0;

	list_for_each_entry(request, &ring->request_list, list) {
		/*
		 * The request queue is per-engine, so can contain requests
		 * from multiple ringbuffers. Here, we must ignore any that
		 * aren't from the ringbuffer we're considering.
		 */
698
		if (request->ringbuf != ringbuf)
699 700 701
			continue;

		/* Would completion of this request free enough space? */
702 703 704
		space = __intel_ring_space(request->postfix, ringbuf->tail,
					   ringbuf->size);
		if (space >= bytes)
705 706 707
			break;
	}

708
	if (WARN_ON(&request->list == &ring->request_list))
709 710 711 712 713 714
		return -ENOSPC;

	ret = i915_wait_request(request);
	if (ret)
		return ret;

715 716
	ringbuf->space = space;
	return 0;
717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817
}

/*
 * intel_logical_ring_advance_and_submit() - advance the tail and submit the workload
 * @ringbuf: Logical Ringbuffer to advance.
 *
 * The tail is updated in our logical ringbuffer struct, not in the actual context. What
 * really happens during submission is that the context and current tail will be placed
 * on a queue waiting for the ELSP to be ready to accept a new context submission. At that
 * point, the tail *inside* the context is updated and the ELSP written to.
 */
static void
intel_logical_ring_advance_and_submit(struct intel_ringbuffer *ringbuf,
				      struct intel_context *ctx,
				      struct drm_i915_gem_request *request)
{
	struct intel_engine_cs *ring = ringbuf->ring;

	intel_logical_ring_advance(ringbuf);

	if (intel_ring_stopped(ring))
		return;

	execlists_context_queue(ring, ctx, ringbuf->tail, request);
}

static int logical_ring_wrap_buffer(struct intel_ringbuffer *ringbuf,
				    struct intel_context *ctx)
{
	uint32_t __iomem *virt;
	int rem = ringbuf->size - ringbuf->tail;

	if (ringbuf->space < rem) {
		int ret = logical_ring_wait_for_space(ringbuf, ctx, rem);

		if (ret)
			return ret;
	}

	virt = ringbuf->virtual_start + ringbuf->tail;
	rem /= 4;
	while (rem--)
		iowrite32(MI_NOOP, virt++);

	ringbuf->tail = 0;
	intel_ring_update_space(ringbuf);

	return 0;
}

static int logical_ring_prepare(struct intel_ringbuffer *ringbuf,
				struct intel_context *ctx, int bytes)
{
	int ret;

	if (unlikely(ringbuf->tail + bytes > ringbuf->effective_size)) {
		ret = logical_ring_wrap_buffer(ringbuf, ctx);
		if (unlikely(ret))
			return ret;
	}

	if (unlikely(ringbuf->space < bytes)) {
		ret = logical_ring_wait_for_space(ringbuf, ctx, bytes);
		if (unlikely(ret))
			return ret;
	}

	return 0;
}

/**
 * intel_logical_ring_begin() - prepare the logical ringbuffer to accept some commands
 *
 * @ringbuf: Logical ringbuffer.
 * @num_dwords: number of DWORDs that we plan to write to the ringbuffer.
 *
 * The ringbuffer might not be ready to accept the commands right away (maybe it needs to
 * be wrapped, or wait a bit for the tail to be updated). This function takes care of that
 * and also preallocates a request (every workload submission is still mediated through
 * requests, same as it did with legacy ringbuffer submission).
 *
 * Return: non-zero if the ringbuffer is not ready to be written to.
 */
static int intel_logical_ring_begin(struct intel_ringbuffer *ringbuf,
				    struct intel_context *ctx, int num_dwords)
{
	struct intel_engine_cs *ring = ringbuf->ring;
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	ret = i915_gem_check_wedge(&dev_priv->gpu_error,
				   dev_priv->mm.interruptible);
	if (ret)
		return ret;

	ret = logical_ring_prepare(ringbuf, ctx, num_dwords * sizeof(uint32_t));
	if (ret)
		return ret;

	/* Preallocate the olr before touching the ring */
818
	ret = i915_gem_request_alloc(ring, ctx);
819 820 821 822 823 824 825
	if (ret)
		return ret;

	ringbuf->space -= num_dwords * sizeof(uint32_t);
	return 0;
}

826 827 828 829 830 831 832 833 834 835
/**
 * execlists_submission() - submit a batchbuffer for execution, Execlists style
 * @dev: DRM device.
 * @file: DRM file.
 * @ring: Engine Command Streamer to submit to.
 * @ctx: Context to employ for this submission.
 * @args: execbuffer call arguments.
 * @vmas: list of vmas.
 * @batch_obj: the batchbuffer to submit.
 * @exec_start: batchbuffer start virtual address pointer.
836
 * @dispatch_flags: translated execbuffer call flags.
837 838 839 840 841 842
 *
 * This is the evil twin version of i915_gem_ringbuffer_submission. It abstracts
 * away the submission details of the execbuffer ioctl call.
 *
 * Return: non-zero if the submission fails.
 */
843 844 845 846 847 848
int intel_execlists_submission(struct drm_device *dev, struct drm_file *file,
			       struct intel_engine_cs *ring,
			       struct intel_context *ctx,
			       struct drm_i915_gem_execbuffer2 *args,
			       struct list_head *vmas,
			       struct drm_i915_gem_object *batch_obj,
849
			       u64 exec_start, u32 dispatch_flags)
850
{
851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
	int instp_mode;
	u32 instp_mask;
	int ret;

	instp_mode = args->flags & I915_EXEC_CONSTANTS_MASK;
	instp_mask = I915_EXEC_CONSTANTS_MASK;
	switch (instp_mode) {
	case I915_EXEC_CONSTANTS_REL_GENERAL:
	case I915_EXEC_CONSTANTS_ABSOLUTE:
	case I915_EXEC_CONSTANTS_REL_SURFACE:
		if (instp_mode != 0 && ring != &dev_priv->ring[RCS]) {
			DRM_DEBUG("non-0 rel constants mode on non-RCS\n");
			return -EINVAL;
		}

		if (instp_mode != dev_priv->relative_constants_mode) {
			if (instp_mode == I915_EXEC_CONSTANTS_REL_SURFACE) {
				DRM_DEBUG("rel surface constants mode invalid on gen5+\n");
				return -EINVAL;
			}

			/* The HW changed the meaning on this bit on gen6 */
			instp_mask &= ~I915_EXEC_CONSTANTS_REL_SURFACE;
		}
		break;
	default:
		DRM_DEBUG("execbuf with unknown constants: %d\n", instp_mode);
		return -EINVAL;
	}

	if (args->num_cliprects != 0) {
		DRM_DEBUG("clip rectangles are only valid on pre-gen5\n");
		return -EINVAL;
	} else {
		if (args->DR4 == 0xffffffff) {
			DRM_DEBUG("UXA submitting garbage DR4, fixing up\n");
			args->DR4 = 0;
		}

		if (args->DR1 || args->DR4 || args->cliprects_ptr) {
			DRM_DEBUG("0 cliprects but dirt in cliprects fields\n");
			return -EINVAL;
		}
	}

	if (args->flags & I915_EXEC_GEN7_SOL_RESET) {
		DRM_DEBUG("sol reset is gen7 only\n");
		return -EINVAL;
	}

903
	ret = execlists_move_to_gpu(ringbuf, ctx, vmas);
904 905 906 907 908
	if (ret)
		return ret;

	if (ring == &dev_priv->ring[RCS] &&
	    instp_mode != dev_priv->relative_constants_mode) {
909
		ret = intel_logical_ring_begin(ringbuf, ctx, 4);
910 911 912 913 914 915 916 917 918 919 920 921
		if (ret)
			return ret;

		intel_logical_ring_emit(ringbuf, MI_NOOP);
		intel_logical_ring_emit(ringbuf, MI_LOAD_REGISTER_IMM(1));
		intel_logical_ring_emit(ringbuf, INSTPM);
		intel_logical_ring_emit(ringbuf, instp_mask << 16 | instp_mode);
		intel_logical_ring_advance(ringbuf);

		dev_priv->relative_constants_mode = instp_mode;
	}

922
	ret = ring->emit_bb_start(ringbuf, ctx, exec_start, dispatch_flags);
923 924 925
	if (ret)
		return ret;

926 927
	trace_i915_gem_ring_dispatch(intel_ring_get_request(ring), dispatch_flags);

928 929 930
	i915_gem_execbuffer_move_to_active(vmas, ring);
	i915_gem_execbuffer_retire_commands(dev, file, ring, batch_obj);

931 932 933
	return 0;
}

934 935
void intel_execlists_retire_requests(struct intel_engine_cs *ring)
{
936
	struct drm_i915_gem_request *req, *tmp;
937 938 939 940 941 942 943
	struct list_head retired_list;

	WARN_ON(!mutex_is_locked(&ring->dev->struct_mutex));
	if (list_empty(&ring->execlist_retired_req_list))
		return;

	INIT_LIST_HEAD(&retired_list);
944
	spin_lock_irq(&ring->execlist_lock);
945
	list_replace_init(&ring->execlist_retired_req_list, &retired_list);
946
	spin_unlock_irq(&ring->execlist_lock);
947 948

	list_for_each_entry_safe(req, tmp, &retired_list, execlist_link) {
949
		struct intel_context *ctx = req->ctx;
950 951 952 953 954
		struct drm_i915_gem_object *ctx_obj =
				ctx->engine[ring->id].state;

		if (ctx_obj && (ctx != ring->default_context))
			intel_lr_context_unpin(ring, ctx);
955
		list_del(&req->execlist_link);
956
		i915_gem_request_unreference(req);
957 958 959
	}
}

960 961
void intel_logical_ring_stop(struct intel_engine_cs *ring)
{
962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979
	struct drm_i915_private *dev_priv = ring->dev->dev_private;
	int ret;

	if (!intel_ring_initialized(ring))
		return;

	ret = intel_ring_idle(ring);
	if (ret && !i915_reset_in_progress(&to_i915(ring->dev)->gpu_error))
		DRM_ERROR("failed to quiesce %s whilst cleaning up: %d\n",
			  ring->name, ret);

	/* TODO: Is this correct with Execlists enabled? */
	I915_WRITE_MODE(ring, _MASKED_BIT_ENABLE(STOP_RING));
	if (wait_for_atomic((I915_READ_MODE(ring) & MODE_IDLE) != 0, 1000)) {
		DRM_ERROR("%s :timed out trying to stop ring\n", ring->name);
		return;
	}
	I915_WRITE_MODE(ring, _MASKED_BIT_DISABLE(STOP_RING));
980 981
}

982 983
int logical_ring_flush_all_caches(struct intel_ringbuffer *ringbuf,
				  struct intel_context *ctx)
984 985 986 987 988 989 990
{
	struct intel_engine_cs *ring = ringbuf->ring;
	int ret;

	if (!ring->gpu_caches_dirty)
		return 0;

991
	ret = ring->emit_flush(ringbuf, ctx, 0, I915_GEM_GPU_DOMAINS);
992 993 994 995 996 997 998
	if (ret)
		return ret;

	ring->gpu_caches_dirty = false;
	return 0;
}

999 1000 1001 1002
static int intel_lr_context_pin(struct intel_engine_cs *ring,
		struct intel_context *ctx)
{
	struct drm_i915_gem_object *ctx_obj = ctx->engine[ring->id].state;
1003
	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
1004 1005 1006
	int ret = 0;

	WARN_ON(!mutex_is_locked(&ring->dev->struct_mutex));
1007
	if (ctx->engine[ring->id].pin_count++ == 0) {
1008 1009 1010
		ret = i915_gem_obj_ggtt_pin(ctx_obj,
				GEN8_LR_CONTEXT_ALIGN, 0);
		if (ret)
1011
			goto reset_pin_count;
1012 1013 1014 1015

		ret = intel_pin_and_map_ringbuffer_obj(ring->dev, ringbuf);
		if (ret)
			goto unpin_ctx_obj;
1016 1017
	}

1018 1019 1020 1021
	return ret;

unpin_ctx_obj:
	i915_gem_object_ggtt_unpin(ctx_obj);
1022 1023
reset_pin_count:
	ctx->engine[ring->id].pin_count = 0;
1024

1025 1026 1027 1028 1029 1030 1031
	return ret;
}

void intel_lr_context_unpin(struct intel_engine_cs *ring,
		struct intel_context *ctx)
{
	struct drm_i915_gem_object *ctx_obj = ctx->engine[ring->id].state;
1032
	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
1033 1034 1035

	if (ctx_obj) {
		WARN_ON(!mutex_is_locked(&ring->dev->struct_mutex));
1036
		if (--ctx->engine[ring->id].pin_count == 0) {
1037
			intel_unpin_ringbuffer_obj(ringbuf);
1038
			i915_gem_object_ggtt_unpin(ctx_obj);
1039
		}
1040 1041 1042
	}
}

1043 1044 1045 1046 1047 1048 1049 1050 1051
static int intel_logical_ring_workarounds_emit(struct intel_engine_cs *ring,
					       struct intel_context *ctx)
{
	int ret, i;
	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct i915_workarounds *w = &dev_priv->workarounds;

1052
	if (WARN_ON_ONCE(w->count == 0))
1053 1054 1055
		return 0;

	ring->gpu_caches_dirty = true;
1056
	ret = logical_ring_flush_all_caches(ringbuf, ctx);
1057 1058 1059
	if (ret)
		return ret;

1060
	ret = intel_logical_ring_begin(ringbuf, ctx, w->count * 2 + 2);
1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073
	if (ret)
		return ret;

	intel_logical_ring_emit(ringbuf, MI_LOAD_REGISTER_IMM(w->count));
	for (i = 0; i < w->count; i++) {
		intel_logical_ring_emit(ringbuf, w->reg[i].addr);
		intel_logical_ring_emit(ringbuf, w->reg[i].value);
	}
	intel_logical_ring_emit(ringbuf, MI_NOOP);

	intel_logical_ring_advance(ringbuf);

	ring->gpu_caches_dirty = true;
1074
	ret = logical_ring_flush_all_caches(ringbuf, ctx);
1075 1076 1077 1078 1079 1080
	if (ret)
		return ret;

	return 0;
}

1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
#define wa_ctx_emit(batch, cmd)						\
	do {								\
		if (WARN_ON(index >= (PAGE_SIZE / sizeof(uint32_t)))) {	\
			return -ENOSPC;					\
		}							\
		batch[index++] = (cmd);					\
	} while (0)

static inline uint32_t wa_ctx_start(struct i915_wa_ctx_bb *wa_ctx,
				    uint32_t offset,
				    uint32_t start_alignment)
{
	return wa_ctx->offset = ALIGN(offset, start_alignment);
}

static inline int wa_ctx_end(struct i915_wa_ctx_bb *wa_ctx,
			     uint32_t offset,
			     uint32_t size_alignment)
{
	wa_ctx->size = offset - wa_ctx->offset;

	WARN(wa_ctx->size % size_alignment,
	     "wa_ctx_bb failed sanity checks: size %d is not aligned to %d\n",
	     wa_ctx->size, size_alignment);
	return 0;
}

/**
 * gen8_init_indirectctx_bb() - initialize indirect ctx batch with WA
 *
 * @ring: only applicable for RCS
 * @wa_ctx: structure representing wa_ctx
 *  offset: specifies start of the batch, should be cache-aligned. This is updated
 *    with the offset value received as input.
 *  size: size of the batch in DWORDS but HW expects in terms of cachelines
 * @batch: page in which WA are loaded
 * @offset: This field specifies the start of the batch, it should be
 *  cache-aligned otherwise it is adjusted accordingly.
 *  Typically we only have one indirect_ctx and per_ctx batch buffer which are
 *  initialized at the beginning and shared across all contexts but this field
 *  helps us to have multiple batches at different offsets and select them based
 *  on a criteria. At the moment this batch always start at the beginning of the page
 *  and at this point we don't have multiple wa_ctx batch buffers.
 *
 *  The number of WA applied are not known at the beginning; we use this field
 *  to return the no of DWORDS written.

 *  It is to be noted that this batch does not contain MI_BATCH_BUFFER_END
 *  so it adds NOOPs as padding to make it cacheline aligned.
 *  MI_BATCH_BUFFER_END will be added to perctx batch and both of them together
 *  makes a complete batch buffer.
 *
 * Return: non-zero if we exceed the PAGE_SIZE limit.
 */

static int gen8_init_indirectctx_bb(struct intel_engine_cs *ring,
				    struct i915_wa_ctx_bb *wa_ctx,
				    uint32_t *const batch,
				    uint32_t *offset)
{
	uint32_t index = wa_ctx_start(wa_ctx, *offset, CACHELINE_DWORDS);

1143 1144
	/* WaDisableCtxRestoreArbitration:bdw,chv */
	wa_ctx_emit(batch, MI_ARB_ON_OFF | MI_ARB_DISABLE);
1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181

	/* Pad to end of cacheline */
	while (index % CACHELINE_DWORDS)
		wa_ctx_emit(batch, MI_NOOP);

	/*
	 * MI_BATCH_BUFFER_END is not required in Indirect ctx BB because
	 * execution depends on the length specified in terms of cache lines
	 * in the register CTX_RCS_INDIRECT_CTX
	 */

	return wa_ctx_end(wa_ctx, *offset = index, CACHELINE_DWORDS);
}

/**
 * gen8_init_perctx_bb() - initialize per ctx batch with WA
 *
 * @ring: only applicable for RCS
 * @wa_ctx: structure representing wa_ctx
 *  offset: specifies start of the batch, should be cache-aligned.
 *  size: size of the batch in DWORDS but HW expects in terms of cachelines
 * @offset: This field specifies the start of this batch.
 *   This batch is started immediately after indirect_ctx batch. Since we ensure
 *   that indirect_ctx ends on a cacheline this batch is aligned automatically.
 *
 *   The number of DWORDS written are returned using this field.
 *
 *  This batch is terminated with MI_BATCH_BUFFER_END and so we need not add padding
 *  to align it with cacheline as padding after MI_BATCH_BUFFER_END is redundant.
 */
static int gen8_init_perctx_bb(struct intel_engine_cs *ring,
			       struct i915_wa_ctx_bb *wa_ctx,
			       uint32_t *const batch,
			       uint32_t *offset)
{
	uint32_t index = wa_ctx_start(wa_ctx, *offset, CACHELINE_DWORDS);

1182 1183 1184
	/* WaDisableCtxRestoreArbitration:bdw,chv */
	wa_ctx_emit(batch, MI_ARB_ON_OFF | MI_ARB_ENABLE);

1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229
	wa_ctx_emit(batch, MI_BATCH_BUFFER_END);

	return wa_ctx_end(wa_ctx, *offset = index, 1);
}

static int lrc_setup_wa_ctx_obj(struct intel_engine_cs *ring, u32 size)
{
	int ret;

	ring->wa_ctx.obj = i915_gem_alloc_object(ring->dev, PAGE_ALIGN(size));
	if (!ring->wa_ctx.obj) {
		DRM_DEBUG_DRIVER("alloc LRC WA ctx backing obj failed.\n");
		return -ENOMEM;
	}

	ret = i915_gem_obj_ggtt_pin(ring->wa_ctx.obj, PAGE_SIZE, 0);
	if (ret) {
		DRM_DEBUG_DRIVER("pin LRC WA ctx backing obj failed: %d\n",
				 ret);
		drm_gem_object_unreference(&ring->wa_ctx.obj->base);
		return ret;
	}

	return 0;
}

static void lrc_destroy_wa_ctx_obj(struct intel_engine_cs *ring)
{
	if (ring->wa_ctx.obj) {
		i915_gem_object_ggtt_unpin(ring->wa_ctx.obj);
		drm_gem_object_unreference(&ring->wa_ctx.obj->base);
		ring->wa_ctx.obj = NULL;
	}
}

static int intel_init_workaround_bb(struct intel_engine_cs *ring)
{
	int ret;
	uint32_t *batch;
	uint32_t offset;
	struct page *page;
	struct i915_ctx_workarounds *wa_ctx = &ring->wa_ctx;

	WARN_ON(ring->id != RCS);

1230 1231 1232 1233 1234 1235
	/* some WA perform writes to scratch page, ensure it is valid */
	if (ring->scratch.obj == NULL) {
		DRM_ERROR("scratch page not allocated for %s\n", ring->name);
		return -EINVAL;
	}

1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
	ret = lrc_setup_wa_ctx_obj(ring, PAGE_SIZE);
	if (ret) {
		DRM_DEBUG_DRIVER("Failed to setup context WA page: %d\n", ret);
		return ret;
	}

	page = i915_gem_object_get_page(wa_ctx->obj, 0);
	batch = kmap_atomic(page);
	offset = 0;

	if (INTEL_INFO(ring->dev)->gen == 8) {
		ret = gen8_init_indirectctx_bb(ring,
					       &wa_ctx->indirect_ctx,
					       batch,
					       &offset);
		if (ret)
			goto out;

		ret = gen8_init_perctx_bb(ring,
					  &wa_ctx->per_ctx,
					  batch,
					  &offset);
		if (ret)
			goto out;
	} else {
		WARN(INTEL_INFO(ring->dev)->gen >= 8,
		     "WA batch buffer is not initialized for Gen%d\n",
		     INTEL_INFO(ring->dev)->gen);
		lrc_destroy_wa_ctx_obj(ring);
	}

out:
	kunmap_atomic(batch);
	if (ret)
		lrc_destroy_wa_ctx_obj(ring);

	return ret;
}

1275 1276 1277 1278 1279
static int gen8_init_common_ring(struct intel_engine_cs *ring)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

1280 1281 1282
	I915_WRITE_IMR(ring, ~(ring->irq_enable_mask | ring->irq_keep_mask));
	I915_WRITE(RING_HWSTAM(ring->mmio_base), 0xffffffff);

1283 1284 1285 1286
	I915_WRITE(RING_MODE_GEN7(ring),
		   _MASKED_BIT_DISABLE(GFX_REPLAY_MODE) |
		   _MASKED_BIT_ENABLE(GFX_RUN_LIST_ENABLE));
	POSTING_READ(RING_MODE_GEN7(ring));
1287
	ring->next_context_status_buffer = 0;
1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314
	DRM_DEBUG_DRIVER("Execlists enabled for %s\n", ring->name);

	memset(&ring->hangcheck, 0, sizeof(ring->hangcheck));

	return 0;
}

static int gen8_init_render_ring(struct intel_engine_cs *ring)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

	ret = gen8_init_common_ring(ring);
	if (ret)
		return ret;

	/* We need to disable the AsyncFlip performance optimisations in order
	 * to use MI_WAIT_FOR_EVENT within the CS. It should already be
	 * programmed to '1' on all products.
	 *
	 * WaDisableAsyncFlipPerfMode:snb,ivb,hsw,vlv,bdw,chv
	 */
	I915_WRITE(MI_MODE, _MASKED_BIT_ENABLE(ASYNC_FLIP_PERF_DISABLE));

	I915_WRITE(INSTPM, _MASKED_BIT_ENABLE(INSTPM_FORCE_ORDERING));

1315
	return init_workarounds_ring(ring);
1316 1317
}

1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328
static int gen9_init_render_ring(struct intel_engine_cs *ring)
{
	int ret;

	ret = gen8_init_common_ring(ring);
	if (ret)
		return ret;

	return init_workarounds_ring(ring);
}

1329
static int gen8_emit_bb_start(struct intel_ringbuffer *ringbuf,
1330
			      struct intel_context *ctx,
1331
			      u64 offset, unsigned dispatch_flags)
1332
{
1333
	bool ppgtt = !(dispatch_flags & I915_DISPATCH_SECURE);
1334 1335
	int ret;

1336
	ret = intel_logical_ring_begin(ringbuf, ctx, 4);
1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349
	if (ret)
		return ret;

	/* FIXME(BDW): Address space and security selectors. */
	intel_logical_ring_emit(ringbuf, MI_BATCH_BUFFER_START_GEN8 | (ppgtt<<8));
	intel_logical_ring_emit(ringbuf, lower_32_bits(offset));
	intel_logical_ring_emit(ringbuf, upper_32_bits(offset));
	intel_logical_ring_emit(ringbuf, MI_NOOP);
	intel_logical_ring_advance(ringbuf);

	return 0;
}

1350 1351 1352 1353 1354 1355
static bool gen8_logical_ring_get_irq(struct intel_engine_cs *ring)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	unsigned long flags;

1356
	if (WARN_ON(!intel_irqs_enabled(dev_priv)))
1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382
		return false;

	spin_lock_irqsave(&dev_priv->irq_lock, flags);
	if (ring->irq_refcount++ == 0) {
		I915_WRITE_IMR(ring, ~(ring->irq_enable_mask | ring->irq_keep_mask));
		POSTING_READ(RING_IMR(ring->mmio_base));
	}
	spin_unlock_irqrestore(&dev_priv->irq_lock, flags);

	return true;
}

static void gen8_logical_ring_put_irq(struct intel_engine_cs *ring)
{
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	unsigned long flags;

	spin_lock_irqsave(&dev_priv->irq_lock, flags);
	if (--ring->irq_refcount == 0) {
		I915_WRITE_IMR(ring, ~ring->irq_keep_mask);
		POSTING_READ(RING_IMR(ring->mmio_base));
	}
	spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
}

1383
static int gen8_emit_flush(struct intel_ringbuffer *ringbuf,
1384
			   struct intel_context *ctx,
1385 1386 1387 1388 1389 1390 1391 1392 1393
			   u32 invalidate_domains,
			   u32 unused)
{
	struct intel_engine_cs *ring = ringbuf->ring;
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	uint32_t cmd;
	int ret;

1394
	ret = intel_logical_ring_begin(ringbuf, ctx, 4);
1395 1396 1397 1398 1399
	if (ret)
		return ret;

	cmd = MI_FLUSH_DW + 1;

1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410
	/* We always require a command barrier so that subsequent
	 * commands, such as breadcrumb interrupts, are strictly ordered
	 * wrt the contents of the write cache being flushed to memory
	 * (and thus being coherent from the CPU).
	 */
	cmd |= MI_FLUSH_DW_STORE_INDEX | MI_FLUSH_DW_OP_STOREDW;

	if (invalidate_domains & I915_GEM_GPU_DOMAINS) {
		cmd |= MI_INVALIDATE_TLB;
		if (ring == &dev_priv->ring[VCS])
			cmd |= MI_INVALIDATE_BSD;
1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424
	}

	intel_logical_ring_emit(ringbuf, cmd);
	intel_logical_ring_emit(ringbuf,
				I915_GEM_HWS_SCRATCH_ADDR |
				MI_FLUSH_DW_USE_GTT);
	intel_logical_ring_emit(ringbuf, 0); /* upper addr */
	intel_logical_ring_emit(ringbuf, 0); /* value */
	intel_logical_ring_advance(ringbuf);

	return 0;
}

static int gen8_emit_flush_render(struct intel_ringbuffer *ringbuf,
1425
				  struct intel_context *ctx,
1426 1427 1428 1429 1430
				  u32 invalidate_domains,
				  u32 flush_domains)
{
	struct intel_engine_cs *ring = ringbuf->ring;
	u32 scratch_addr = ring->scratch.gtt_offset + 2 * CACHELINE_BYTES;
1431
	bool vf_flush_wa;
1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452
	u32 flags = 0;
	int ret;

	flags |= PIPE_CONTROL_CS_STALL;

	if (flush_domains) {
		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
	}

	if (invalidate_domains) {
		flags |= PIPE_CONTROL_TLB_INVALIDATE;
		flags |= PIPE_CONTROL_INSTRUCTION_CACHE_INVALIDATE;
		flags |= PIPE_CONTROL_TEXTURE_CACHE_INVALIDATE;
		flags |= PIPE_CONTROL_VF_CACHE_INVALIDATE;
		flags |= PIPE_CONTROL_CONST_CACHE_INVALIDATE;
		flags |= PIPE_CONTROL_STATE_CACHE_INVALIDATE;
		flags |= PIPE_CONTROL_QW_WRITE;
		flags |= PIPE_CONTROL_GLOBAL_GTT_IVB;
	}

1453 1454 1455 1456 1457 1458 1459 1460
	/*
	 * On GEN9+ Before VF_CACHE_INVALIDATE we need to emit a NULL pipe
	 * control.
	 */
	vf_flush_wa = INTEL_INFO(ring->dev)->gen >= 9 &&
		      flags & PIPE_CONTROL_VF_CACHE_INVALIDATE;

	ret = intel_logical_ring_begin(ringbuf, ctx, vf_flush_wa ? 12 : 6);
1461 1462 1463
	if (ret)
		return ret;

1464 1465 1466 1467 1468 1469 1470 1471 1472
	if (vf_flush_wa) {
		intel_logical_ring_emit(ringbuf, GFX_OP_PIPE_CONTROL(6));
		intel_logical_ring_emit(ringbuf, 0);
		intel_logical_ring_emit(ringbuf, 0);
		intel_logical_ring_emit(ringbuf, 0);
		intel_logical_ring_emit(ringbuf, 0);
		intel_logical_ring_emit(ringbuf, 0);
	}

1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483
	intel_logical_ring_emit(ringbuf, GFX_OP_PIPE_CONTROL(6));
	intel_logical_ring_emit(ringbuf, flags);
	intel_logical_ring_emit(ringbuf, scratch_addr);
	intel_logical_ring_emit(ringbuf, 0);
	intel_logical_ring_emit(ringbuf, 0);
	intel_logical_ring_emit(ringbuf, 0);
	intel_logical_ring_advance(ringbuf);

	return 0;
}

1484 1485 1486 1487 1488 1489 1490 1491 1492 1493
static u32 gen8_get_seqno(struct intel_engine_cs *ring, bool lazy_coherency)
{
	return intel_read_status_page(ring, I915_GEM_HWS_INDEX);
}

static void gen8_set_seqno(struct intel_engine_cs *ring, u32 seqno)
{
	intel_write_status_page(ring, I915_GEM_HWS_INDEX, seqno);
}

1494 1495
static int gen8_emit_request(struct intel_ringbuffer *ringbuf,
			     struct drm_i915_gem_request *request)
1496 1497 1498 1499 1500
{
	struct intel_engine_cs *ring = ringbuf->ring;
	u32 cmd;
	int ret;

1501 1502 1503 1504 1505 1506
	/*
	 * Reserve space for 2 NOOPs at the end of each request to be
	 * used as a workaround for not being allowed to do lite
	 * restore with HEAD==TAIL (WaIdleLiteRestore).
	 */
	ret = intel_logical_ring_begin(ringbuf, request->ctx, 8);
1507 1508 1509
	if (ret)
		return ret;

1510
	cmd = MI_STORE_DWORD_IMM_GEN4;
1511 1512 1513 1514 1515 1516 1517
	cmd |= MI_GLOBAL_GTT;

	intel_logical_ring_emit(ringbuf, cmd);
	intel_logical_ring_emit(ringbuf,
				(ring->status_page.gfx_addr +
				(I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT)));
	intel_logical_ring_emit(ringbuf, 0);
1518 1519
	intel_logical_ring_emit(ringbuf,
		i915_gem_request_get_seqno(ring->outstanding_lazy_request));
1520 1521
	intel_logical_ring_emit(ringbuf, MI_USER_INTERRUPT);
	intel_logical_ring_emit(ringbuf, MI_NOOP);
1522
	intel_logical_ring_advance_and_submit(ringbuf, request->ctx, request);
1523

1524 1525 1526 1527 1528 1529 1530 1531
	/*
	 * Here we add two extra NOOPs as padding to avoid
	 * lite restore of a context with HEAD==TAIL.
	 */
	intel_logical_ring_emit(ringbuf, MI_NOOP);
	intel_logical_ring_emit(ringbuf, MI_NOOP);
	intel_logical_ring_advance(ringbuf);

1532 1533 1534
	return 0;
}

1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567
static int intel_lr_context_render_state_init(struct intel_engine_cs *ring,
					      struct intel_context *ctx)
{
	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
	struct render_state so;
	struct drm_i915_file_private *file_priv = ctx->file_priv;
	struct drm_file *file = file_priv ? file_priv->file : NULL;
	int ret;

	ret = i915_gem_render_state_prepare(ring, &so);
	if (ret)
		return ret;

	if (so.rodata == NULL)
		return 0;

	ret = ring->emit_bb_start(ringbuf,
			ctx,
			so.ggtt_offset,
			I915_DISPATCH_SECURE);
	if (ret)
		goto out;

	i915_vma_move_to_active(i915_gem_obj_to_ggtt(so.obj), ring);

	ret = __i915_add_request(ring, file, so.obj);
	/* intel_logical_ring_add_request moves object to inactive if it
	 * fails */
out:
	i915_gem_render_state_fini(&so);
	return ret;
}

1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579
static int gen8_init_rcs_context(struct intel_engine_cs *ring,
		       struct intel_context *ctx)
{
	int ret;

	ret = intel_logical_ring_workarounds_emit(ring, ctx);
	if (ret)
		return ret;

	return intel_lr_context_render_state_init(ring, ctx);
}

1580 1581 1582 1583 1584 1585
/**
 * intel_logical_ring_cleanup() - deallocate the Engine Command Streamer
 *
 * @ring: Engine Command Streamer.
 *
 */
1586 1587
void intel_logical_ring_cleanup(struct intel_engine_cs *ring)
{
1588
	struct drm_i915_private *dev_priv;
1589

1590 1591 1592
	if (!intel_ring_initialized(ring))
		return;

1593 1594
	dev_priv = ring->dev->dev_private;

1595 1596
	intel_logical_ring_stop(ring);
	WARN_ON((I915_READ_MODE(ring) & MODE_IDLE) == 0);
1597
	i915_gem_request_assign(&ring->outstanding_lazy_request, NULL);
1598 1599 1600 1601 1602

	if (ring->cleanup)
		ring->cleanup(ring);

	i915_cmd_parser_fini_ring(ring);
1603
	i915_gem_batch_pool_fini(&ring->batch_pool);
1604 1605 1606 1607 1608

	if (ring->status_page.obj) {
		kunmap(sg_page(ring->status_page.obj->pages->sgl));
		ring->status_page.obj = NULL;
	}
1609 1610

	lrc_destroy_wa_ctx_obj(ring);
1611 1612 1613 1614
}

static int logical_ring_init(struct drm_device *dev, struct intel_engine_cs *ring)
{
1615 1616 1617 1618 1619 1620 1621 1622
	int ret;

	/* Intentionally left blank. */
	ring->buffer = NULL;

	ring->dev = dev;
	INIT_LIST_HEAD(&ring->active_list);
	INIT_LIST_HEAD(&ring->request_list);
1623
	i915_gem_batch_pool_init(dev, &ring->batch_pool);
1624 1625
	init_waitqueue_head(&ring->irq_queue);

1626
	INIT_LIST_HEAD(&ring->execlist_queue);
1627
	INIT_LIST_HEAD(&ring->execlist_retired_req_list);
1628 1629
	spin_lock_init(&ring->execlist_lock);

1630 1631 1632 1633
	ret = i915_cmd_parser_init_ring(ring);
	if (ret)
		return ret;

1634 1635 1636
	ret = intel_lr_context_deferred_create(ring->default_context, ring);

	return ret;
1637 1638 1639 1640 1641 1642
}

static int logical_render_ring_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring = &dev_priv->ring[RCS];
1643
	int ret;
1644 1645 1646 1647 1648 1649

	ring->name = "render ring";
	ring->id = RCS;
	ring->mmio_base = RENDER_RING_BASE;
	ring->irq_enable_mask =
		GT_RENDER_USER_INTERRUPT << GEN8_RCS_IRQ_SHIFT;
1650 1651 1652 1653
	ring->irq_keep_mask =
		GT_CONTEXT_SWITCH_INTERRUPT << GEN8_RCS_IRQ_SHIFT;
	if (HAS_L3_DPF(dev))
		ring->irq_keep_mask |= GT_RENDER_L3_PARITY_ERROR_INTERRUPT;
1654

1655 1656 1657 1658
	if (INTEL_INFO(dev)->gen >= 9)
		ring->init_hw = gen9_init_render_ring;
	else
		ring->init_hw = gen8_init_render_ring;
1659
	ring->init_context = gen8_init_rcs_context;
1660
	ring->cleanup = intel_fini_pipe_control;
1661 1662
	ring->get_seqno = gen8_get_seqno;
	ring->set_seqno = gen8_set_seqno;
1663
	ring->emit_request = gen8_emit_request;
1664
	ring->emit_flush = gen8_emit_flush_render;
1665 1666
	ring->irq_get = gen8_logical_ring_get_irq;
	ring->irq_put = gen8_logical_ring_put_irq;
1667
	ring->emit_bb_start = gen8_emit_bb_start;
1668

1669
	ring->dev = dev;
1670 1671

	ret = intel_init_pipe_control(ring);
1672 1673 1674
	if (ret)
		return ret;

1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685
	ret = intel_init_workaround_bb(ring);
	if (ret) {
		/*
		 * We continue even if we fail to initialize WA batch
		 * because we only expect rare glitches but nothing
		 * critical to prevent us from using GPU
		 */
		DRM_ERROR("WA batch buffer initialization failed: %d\n",
			  ret);
	}

1686 1687
	ret = logical_ring_init(dev, ring);
	if (ret) {
1688
		lrc_destroy_wa_ctx_obj(ring);
1689
	}
1690 1691

	return ret;
1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703
}

static int logical_bsd_ring_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring = &dev_priv->ring[VCS];

	ring->name = "bsd ring";
	ring->id = VCS;
	ring->mmio_base = GEN6_BSD_RING_BASE;
	ring->irq_enable_mask =
		GT_RENDER_USER_INTERRUPT << GEN8_VCS1_IRQ_SHIFT;
1704 1705
	ring->irq_keep_mask =
		GT_CONTEXT_SWITCH_INTERRUPT << GEN8_VCS1_IRQ_SHIFT;
1706

1707
	ring->init_hw = gen8_init_common_ring;
1708 1709
	ring->get_seqno = gen8_get_seqno;
	ring->set_seqno = gen8_set_seqno;
1710
	ring->emit_request = gen8_emit_request;
1711
	ring->emit_flush = gen8_emit_flush;
1712 1713
	ring->irq_get = gen8_logical_ring_get_irq;
	ring->irq_put = gen8_logical_ring_put_irq;
1714
	ring->emit_bb_start = gen8_emit_bb_start;
1715

1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728
	return logical_ring_init(dev, ring);
}

static int logical_bsd2_ring_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring = &dev_priv->ring[VCS2];

	ring->name = "bds2 ring";
	ring->id = VCS2;
	ring->mmio_base = GEN8_BSD2_RING_BASE;
	ring->irq_enable_mask =
		GT_RENDER_USER_INTERRUPT << GEN8_VCS2_IRQ_SHIFT;
1729 1730
	ring->irq_keep_mask =
		GT_CONTEXT_SWITCH_INTERRUPT << GEN8_VCS2_IRQ_SHIFT;
1731

1732
	ring->init_hw = gen8_init_common_ring;
1733 1734
	ring->get_seqno = gen8_get_seqno;
	ring->set_seqno = gen8_set_seqno;
1735
	ring->emit_request = gen8_emit_request;
1736
	ring->emit_flush = gen8_emit_flush;
1737 1738
	ring->irq_get = gen8_logical_ring_get_irq;
	ring->irq_put = gen8_logical_ring_put_irq;
1739
	ring->emit_bb_start = gen8_emit_bb_start;
1740

1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753
	return logical_ring_init(dev, ring);
}

static int logical_blt_ring_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring = &dev_priv->ring[BCS];

	ring->name = "blitter ring";
	ring->id = BCS;
	ring->mmio_base = BLT_RING_BASE;
	ring->irq_enable_mask =
		GT_RENDER_USER_INTERRUPT << GEN8_BCS_IRQ_SHIFT;
1754 1755
	ring->irq_keep_mask =
		GT_CONTEXT_SWITCH_INTERRUPT << GEN8_BCS_IRQ_SHIFT;
1756

1757
	ring->init_hw = gen8_init_common_ring;
1758 1759
	ring->get_seqno = gen8_get_seqno;
	ring->set_seqno = gen8_set_seqno;
1760
	ring->emit_request = gen8_emit_request;
1761
	ring->emit_flush = gen8_emit_flush;
1762 1763
	ring->irq_get = gen8_logical_ring_get_irq;
	ring->irq_put = gen8_logical_ring_put_irq;
1764
	ring->emit_bb_start = gen8_emit_bb_start;
1765

1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778
	return logical_ring_init(dev, ring);
}

static int logical_vebox_ring_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring = &dev_priv->ring[VECS];

	ring->name = "video enhancement ring";
	ring->id = VECS;
	ring->mmio_base = VEBOX_RING_BASE;
	ring->irq_enable_mask =
		GT_RENDER_USER_INTERRUPT << GEN8_VECS_IRQ_SHIFT;
1779 1780
	ring->irq_keep_mask =
		GT_CONTEXT_SWITCH_INTERRUPT << GEN8_VECS_IRQ_SHIFT;
1781

1782
	ring->init_hw = gen8_init_common_ring;
1783 1784
	ring->get_seqno = gen8_get_seqno;
	ring->set_seqno = gen8_set_seqno;
1785
	ring->emit_request = gen8_emit_request;
1786
	ring->emit_flush = gen8_emit_flush;
1787 1788
	ring->irq_get = gen8_logical_ring_get_irq;
	ring->irq_put = gen8_logical_ring_put_irq;
1789
	ring->emit_bb_start = gen8_emit_bb_start;
1790

1791 1792 1793
	return logical_ring_init(dev, ring);
}

1794 1795 1796 1797 1798 1799 1800 1801 1802 1803
/**
 * intel_logical_rings_init() - allocate, populate and init the Engine Command Streamers
 * @dev: DRM device.
 *
 * This function inits the engines for an Execlists submission style (the equivalent in the
 * legacy ringbuffer submission world would be i915_gem_init_rings). It does it only for
 * those engines that are present in the hardware.
 *
 * Return: non-zero if the initialization failed.
 */
1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856
int intel_logical_rings_init(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret;

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

	if (HAS_BSD(dev)) {
		ret = logical_bsd_ring_init(dev);
		if (ret)
			goto cleanup_render_ring;
	}

	if (HAS_BLT(dev)) {
		ret = logical_blt_ring_init(dev);
		if (ret)
			goto cleanup_bsd_ring;
	}

	if (HAS_VEBOX(dev)) {
		ret = logical_vebox_ring_init(dev);
		if (ret)
			goto cleanup_blt_ring;
	}

	if (HAS_BSD2(dev)) {
		ret = logical_bsd2_ring_init(dev);
		if (ret)
			goto cleanup_vebox_ring;
	}

	ret = i915_gem_set_seqno(dev, ((u32)~0 - 0x1000));
	if (ret)
		goto cleanup_bsd2_ring;

	return 0;

cleanup_bsd2_ring:
	intel_logical_ring_cleanup(&dev_priv->ring[VCS2]);
cleanup_vebox_ring:
	intel_logical_ring_cleanup(&dev_priv->ring[VECS]);
cleanup_blt_ring:
	intel_logical_ring_cleanup(&dev_priv->ring[BCS]);
cleanup_bsd_ring:
	intel_logical_ring_cleanup(&dev_priv->ring[VCS]);
cleanup_render_ring:
	intel_logical_ring_cleanup(&dev_priv->ring[RCS]);

	return ret;
}

1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899
static u32
make_rpcs(struct drm_device *dev)
{
	u32 rpcs = 0;

	/*
	 * No explicit RPCS request is needed to ensure full
	 * slice/subslice/EU enablement prior to Gen9.
	*/
	if (INTEL_INFO(dev)->gen < 9)
		return 0;

	/*
	 * Starting in Gen9, render power gating can leave
	 * slice/subslice/EU in a partially enabled state. We
	 * must make an explicit request through RPCS for full
	 * enablement.
	*/
	if (INTEL_INFO(dev)->has_slice_pg) {
		rpcs |= GEN8_RPCS_S_CNT_ENABLE;
		rpcs |= INTEL_INFO(dev)->slice_total <<
			GEN8_RPCS_S_CNT_SHIFT;
		rpcs |= GEN8_RPCS_ENABLE;
	}

	if (INTEL_INFO(dev)->has_subslice_pg) {
		rpcs |= GEN8_RPCS_SS_CNT_ENABLE;
		rpcs |= INTEL_INFO(dev)->subslice_per_slice <<
			GEN8_RPCS_SS_CNT_SHIFT;
		rpcs |= GEN8_RPCS_ENABLE;
	}

	if (INTEL_INFO(dev)->has_eu_pg) {
		rpcs |= INTEL_INFO(dev)->eu_per_subslice <<
			GEN8_RPCS_EU_MIN_SHIFT;
		rpcs |= INTEL_INFO(dev)->eu_per_subslice <<
			GEN8_RPCS_EU_MAX_SHIFT;
		rpcs |= GEN8_RPCS_ENABLE;
	}

	return rpcs;
}

1900 1901 1902 1903
static int
populate_lr_context(struct intel_context *ctx, struct drm_i915_gem_object *ctx_obj,
		    struct intel_engine_cs *ring, struct intel_ringbuffer *ringbuf)
{
1904 1905
	struct drm_device *dev = ring->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
1906
	struct i915_hw_ppgtt *ppgtt = ctx->ppgtt;
1907 1908 1909 1910
	struct page *page;
	uint32_t *reg_state;
	int ret;

1911 1912 1913
	if (!ppgtt)
		ppgtt = dev_priv->mm.aliasing_ppgtt;

1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944
	ret = i915_gem_object_set_to_cpu_domain(ctx_obj, true);
	if (ret) {
		DRM_DEBUG_DRIVER("Could not set to CPU domain\n");
		return ret;
	}

	ret = i915_gem_object_get_pages(ctx_obj);
	if (ret) {
		DRM_DEBUG_DRIVER("Could not get object pages\n");
		return ret;
	}

	i915_gem_object_pin_pages(ctx_obj);

	/* The second page of the context object contains some fields which must
	 * be set up prior to the first execution. */
	page = i915_gem_object_get_page(ctx_obj, 1);
	reg_state = kmap_atomic(page);

	/* A context is actually a big batch buffer with several MI_LOAD_REGISTER_IMM
	 * commands followed by (reg, value) pairs. The values we are setting here are
	 * only for the first context restore: on a subsequent save, the GPU will
	 * recreate this batchbuffer with new values (including all the missing
	 * MI_LOAD_REGISTER_IMM commands that we are not initializing here). */
	if (ring->id == RCS)
		reg_state[CTX_LRI_HEADER_0] = MI_LOAD_REGISTER_IMM(14);
	else
		reg_state[CTX_LRI_HEADER_0] = MI_LOAD_REGISTER_IMM(11);
	reg_state[CTX_LRI_HEADER_0] |= MI_LRI_FORCE_POSTED;
	reg_state[CTX_CONTEXT_CONTROL] = RING_CONTEXT_CONTROL(ring);
	reg_state[CTX_CONTEXT_CONTROL+1] =
1945 1946
		_MASKED_BIT_ENABLE(CTX_CTRL_INHIBIT_SYN_CTX_SWITCH |
				CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);
1947 1948 1949 1950 1951
	reg_state[CTX_RING_HEAD] = RING_HEAD(ring->mmio_base);
	reg_state[CTX_RING_HEAD+1] = 0;
	reg_state[CTX_RING_TAIL] = RING_TAIL(ring->mmio_base);
	reg_state[CTX_RING_TAIL+1] = 0;
	reg_state[CTX_RING_BUFFER_START] = RING_START(ring->mmio_base);
1952 1953 1954
	/* Ring buffer start address is not known until the buffer is pinned.
	 * It is written to the context image in execlists_update_context()
	 */
1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976
	reg_state[CTX_RING_BUFFER_CONTROL] = RING_CTL(ring->mmio_base);
	reg_state[CTX_RING_BUFFER_CONTROL+1] =
			((ringbuf->size - PAGE_SIZE) & RING_NR_PAGES) | RING_VALID;
	reg_state[CTX_BB_HEAD_U] = ring->mmio_base + 0x168;
	reg_state[CTX_BB_HEAD_U+1] = 0;
	reg_state[CTX_BB_HEAD_L] = ring->mmio_base + 0x140;
	reg_state[CTX_BB_HEAD_L+1] = 0;
	reg_state[CTX_BB_STATE] = ring->mmio_base + 0x110;
	reg_state[CTX_BB_STATE+1] = (1<<5);
	reg_state[CTX_SECOND_BB_HEAD_U] = ring->mmio_base + 0x11c;
	reg_state[CTX_SECOND_BB_HEAD_U+1] = 0;
	reg_state[CTX_SECOND_BB_HEAD_L] = ring->mmio_base + 0x114;
	reg_state[CTX_SECOND_BB_HEAD_L+1] = 0;
	reg_state[CTX_SECOND_BB_STATE] = ring->mmio_base + 0x118;
	reg_state[CTX_SECOND_BB_STATE+1] = 0;
	if (ring->id == RCS) {
		reg_state[CTX_BB_PER_CTX_PTR] = ring->mmio_base + 0x1c0;
		reg_state[CTX_BB_PER_CTX_PTR+1] = 0;
		reg_state[CTX_RCS_INDIRECT_CTX] = ring->mmio_base + 0x1c4;
		reg_state[CTX_RCS_INDIRECT_CTX+1] = 0;
		reg_state[CTX_RCS_INDIRECT_CTX_OFFSET] = ring->mmio_base + 0x1c8;
		reg_state[CTX_RCS_INDIRECT_CTX_OFFSET+1] = 0;
1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991
		if (ring->wa_ctx.obj) {
			struct i915_ctx_workarounds *wa_ctx = &ring->wa_ctx;
			uint32_t ggtt_offset = i915_gem_obj_ggtt_offset(wa_ctx->obj);

			reg_state[CTX_RCS_INDIRECT_CTX+1] =
				(ggtt_offset + wa_ctx->indirect_ctx.offset * sizeof(uint32_t)) |
				(wa_ctx->indirect_ctx.size / CACHELINE_DWORDS);

			reg_state[CTX_RCS_INDIRECT_CTX_OFFSET+1] =
				CTX_RCS_INDIRECT_CTX_OFFSET_DEFAULT << 6;

			reg_state[CTX_BB_PER_CTX_PTR+1] =
				(ggtt_offset + wa_ctx->per_ctx.offset * sizeof(uint32_t)) |
				0x01;
		}
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
	}
	reg_state[CTX_LRI_HEADER_1] = MI_LOAD_REGISTER_IMM(9);
	reg_state[CTX_LRI_HEADER_1] |= MI_LRI_FORCE_POSTED;
	reg_state[CTX_CTX_TIMESTAMP] = ring->mmio_base + 0x3a8;
	reg_state[CTX_CTX_TIMESTAMP+1] = 0;
	reg_state[CTX_PDP3_UDW] = GEN8_RING_PDP_UDW(ring, 3);
	reg_state[CTX_PDP3_LDW] = GEN8_RING_PDP_LDW(ring, 3);
	reg_state[CTX_PDP2_UDW] = GEN8_RING_PDP_UDW(ring, 2);
	reg_state[CTX_PDP2_LDW] = GEN8_RING_PDP_LDW(ring, 2);
	reg_state[CTX_PDP1_UDW] = GEN8_RING_PDP_UDW(ring, 1);
	reg_state[CTX_PDP1_LDW] = GEN8_RING_PDP_LDW(ring, 1);
	reg_state[CTX_PDP0_UDW] = GEN8_RING_PDP_UDW(ring, 0);
	reg_state[CTX_PDP0_LDW] = GEN8_RING_PDP_LDW(ring, 0);
2005 2006 2007

	/* With dynamic page allocation, PDPs may not be allocated at this point,
	 * Point the unallocated PDPs to the scratch page
2008 2009 2010 2011 2012
	 */
	ASSIGN_CTX_PDP(ppgtt, reg_state, 3);
	ASSIGN_CTX_PDP(ppgtt, reg_state, 2);
	ASSIGN_CTX_PDP(ppgtt, reg_state, 1);
	ASSIGN_CTX_PDP(ppgtt, reg_state, 0);
2013 2014
	if (ring->id == RCS) {
		reg_state[CTX_LRI_HEADER_2] = MI_LOAD_REGISTER_IMM(1);
2015 2016
		reg_state[CTX_R_PWR_CLK_STATE] = GEN8_R_PWR_CLK_STATE;
		reg_state[CTX_R_PWR_CLK_STATE+1] = make_rpcs(dev);
2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027
	}

	kunmap_atomic(reg_state);

	ctx_obj->dirty = 1;
	set_page_dirty(page);
	i915_gem_object_unpin_pages(ctx_obj);

	return 0;
}

2028 2029 2030 2031 2032 2033 2034 2035
/**
 * intel_lr_context_free() - free the LRC specific bits of a context
 * @ctx: the LR context to free.
 *
 * The real context freeing is done in i915_gem_context_free: this only
 * takes care of the bits that are LRC related: the per-engine backing
 * objects and the logical ringbuffer.
 */
2036 2037
void intel_lr_context_free(struct intel_context *ctx)
{
2038 2039 2040 2041
	int i;

	for (i = 0; i < I915_NUM_RINGS; i++) {
		struct drm_i915_gem_object *ctx_obj = ctx->engine[i].state;
2042

2043
		if (ctx_obj) {
2044 2045 2046 2047
			struct intel_ringbuffer *ringbuf =
					ctx->engine[i].ringbuf;
			struct intel_engine_cs *ring = ringbuf->ring;

2048 2049 2050 2051
			if (ctx == ring->default_context) {
				intel_unpin_ringbuffer_obj(ringbuf);
				i915_gem_object_ggtt_unpin(ctx_obj);
			}
2052
			WARN_ON(ctx->engine[ring->id].pin_count);
2053 2054
			intel_destroy_ringbuffer_obj(ringbuf);
			kfree(ringbuf);
2055 2056 2057 2058 2059 2060 2061 2062 2063
			drm_gem_object_unreference(&ctx_obj->base);
		}
	}
}

static uint32_t get_lr_context_size(struct intel_engine_cs *ring)
{
	int ret = 0;

2064
	WARN_ON(INTEL_INFO(ring->dev)->gen < 8);
2065 2066 2067

	switch (ring->id) {
	case RCS:
2068 2069 2070 2071
		if (INTEL_INFO(ring->dev)->gen >= 9)
			ret = GEN9_LR_CONTEXT_RENDER_SIZE;
		else
			ret = GEN8_LR_CONTEXT_RENDER_SIZE;
2072 2073 2074 2075 2076 2077 2078 2079 2080 2081
		break;
	case VCS:
	case BCS:
	case VECS:
	case VCS2:
		ret = GEN8_LR_CONTEXT_OTHER_SIZE;
		break;
	}

	return ret;
2082 2083
}

2084
static void lrc_setup_hardware_status_page(struct intel_engine_cs *ring,
2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100
		struct drm_i915_gem_object *default_ctx_obj)
{
	struct drm_i915_private *dev_priv = ring->dev->dev_private;

	/* The status page is offset 0 from the default context object
	 * in LRC mode. */
	ring->status_page.gfx_addr = i915_gem_obj_ggtt_offset(default_ctx_obj);
	ring->status_page.page_addr =
			kmap(sg_page(default_ctx_obj->pages->sgl));
	ring->status_page.obj = default_ctx_obj;

	I915_WRITE(RING_HWS_PGA(ring->mmio_base),
			(u32)ring->status_page.gfx_addr);
	POSTING_READ(RING_HWS_PGA(ring->mmio_base));
}

2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111
/**
 * intel_lr_context_deferred_create() - create the LRC specific bits of a context
 * @ctx: LR context to create.
 * @ring: engine to be used with the context.
 *
 * This function can be called more than once, with different engines, if we plan
 * to use the context with them. The context backing objects and the ringbuffers
 * (specially the ringbuffer backing objects) suck a lot of memory up, and that's why
 * the creation is a deferred call: it's better to make sure first that we need to use
 * a given ring with the context.
 *
2112
 * Return: non-zero on error.
2113
 */
2114 2115 2116
int intel_lr_context_deferred_create(struct intel_context *ctx,
				     struct intel_engine_cs *ring)
{
2117
	const bool is_global_default_ctx = (ctx == ring->default_context);
2118 2119 2120
	struct drm_device *dev = ring->dev;
	struct drm_i915_gem_object *ctx_obj;
	uint32_t context_size;
2121
	struct intel_ringbuffer *ringbuf;
2122 2123
	int ret;

2124
	WARN_ON(ctx->legacy_hw_ctx.rcs_state != NULL);
2125
	WARN_ON(ctx->engine[ring->id].state);
2126

2127 2128
	context_size = round_up(get_lr_context_size(ring), 4096);

2129
	ctx_obj = i915_gem_alloc_object(dev, context_size);
2130 2131 2132
	if (!ctx_obj) {
		DRM_DEBUG_DRIVER("Alloc LRC backing obj failed.\n");
		return -ENOMEM;
2133 2134
	}

2135 2136 2137 2138 2139 2140 2141 2142
	if (is_global_default_ctx) {
		ret = i915_gem_obj_ggtt_pin(ctx_obj, GEN8_LR_CONTEXT_ALIGN, 0);
		if (ret) {
			DRM_DEBUG_DRIVER("Pin LRC backing obj failed: %d\n",
					ret);
			drm_gem_object_unreference(&ctx_obj->base);
			return ret;
		}
2143 2144
	}

2145 2146 2147 2148 2149
	ringbuf = kzalloc(sizeof(*ringbuf), GFP_KERNEL);
	if (!ringbuf) {
		DRM_DEBUG_DRIVER("Failed to allocate ringbuffer %s\n",
				ring->name);
		ret = -ENOMEM;
2150
		goto error_unpin_ctx;
2151 2152
	}

2153
	ringbuf->ring = ring;
2154

2155 2156 2157 2158 2159
	ringbuf->size = 32 * PAGE_SIZE;
	ringbuf->effective_size = ringbuf->size;
	ringbuf->head = 0;
	ringbuf->tail = 0;
	ringbuf->last_retired_head = -1;
2160
	intel_ring_update_space(ringbuf);
2161

2162 2163 2164 2165 2166
	if (ringbuf->obj == NULL) {
		ret = intel_alloc_ringbuffer_obj(dev, ringbuf);
		if (ret) {
			DRM_DEBUG_DRIVER(
				"Failed to allocate ringbuffer obj %s: %d\n",
2167
				ring->name, ret);
2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180
			goto error_free_rbuf;
		}

		if (is_global_default_ctx) {
			ret = intel_pin_and_map_ringbuffer_obj(dev, ringbuf);
			if (ret) {
				DRM_ERROR(
					"Failed to pin and map ringbuffer %s: %d\n",
					ring->name, ret);
				goto error_destroy_rbuf;
			}
		}

2181 2182 2183 2184 2185 2186
	}

	ret = populate_lr_context(ctx, ctx_obj, ring, ringbuf);
	if (ret) {
		DRM_DEBUG_DRIVER("Failed to populate LRC: %d\n", ret);
		goto error;
2187 2188 2189
	}

	ctx->engine[ring->id].ringbuf = ringbuf;
2190
	ctx->engine[ring->id].state = ctx_obj;
2191

2192 2193
	if (ctx == ring->default_context)
		lrc_setup_hardware_status_page(ring, ctx_obj);
2194
	else if (ring->id == RCS && !ctx->rcs_initialized) {
2195 2196
		if (ring->init_context) {
			ret = ring->init_context(ring, ctx);
2197
			if (ret) {
2198
				DRM_ERROR("ring init context: %d\n", ret);
2199 2200 2201 2202
				ctx->engine[ring->id].ringbuf = NULL;
				ctx->engine[ring->id].state = NULL;
				goto error;
			}
2203 2204
		}

2205 2206 2207
		ctx->rcs_initialized = true;
	}

2208
	return 0;
2209 2210

error:
2211 2212 2213 2214 2215
	if (is_global_default_ctx)
		intel_unpin_ringbuffer_obj(ringbuf);
error_destroy_rbuf:
	intel_destroy_ringbuffer_obj(ringbuf);
error_free_rbuf:
2216
	kfree(ringbuf);
2217
error_unpin_ctx:
2218 2219
	if (is_global_default_ctx)
		i915_gem_object_ggtt_unpin(ctx_obj);
2220 2221
	drm_gem_object_unreference(&ctx_obj->base);
	return ret;
2222
}
2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257

void intel_lr_context_reset(struct drm_device *dev,
			struct intel_context *ctx)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_engine_cs *ring;
	int i;

	for_each_ring(ring, dev_priv, i) {
		struct drm_i915_gem_object *ctx_obj =
				ctx->engine[ring->id].state;
		struct intel_ringbuffer *ringbuf =
				ctx->engine[ring->id].ringbuf;
		uint32_t *reg_state;
		struct page *page;

		if (!ctx_obj)
			continue;

		if (i915_gem_object_get_pages(ctx_obj)) {
			WARN(1, "Failed get_pages for context obj\n");
			continue;
		}
		page = i915_gem_object_get_page(ctx_obj, 1);
		reg_state = kmap_atomic(page);

		reg_state[CTX_RING_HEAD+1] = 0;
		reg_state[CTX_RING_TAIL+1] = 0;

		kunmap_atomic(reg_state);

		ringbuf->head = 0;
		ringbuf->tail = 0;
	}
}