drivers/gpu/drm/i915/gvt/mmio_context.c - pub/scm/linux/kernel/git/mtd/linux - Git at Google

 /*
  * Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, 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:
  *    Eddie Dong <eddie.dong@intel.com>
  *    Kevin Tian <kevin.tian@intel.com>
  *
  * Contributors:
  *    Zhi Wang <zhi.a.wang@intel.com>
  *    Changbin Du <changbin.du@intel.com>
  *    Zhenyu Wang <zhenyuw@linux.intel.com>
  *    Tina Zhang <tina.zhang@intel.com>
  *    Bing Niu <bing.niu@intel.com>
  *
  */

 #include "i915_drv.h"
 #include "gvt.h"
 #include "trace.h"

 #define GEN9_MOCS_SIZE		64

 /* Raw offset is appened to each line for convenience. */
 static struct engine_mmio gen8_engine_mmio_list[] __cacheline_aligned = {
 	{RCS, GFX_MODE_GEN7, 0xffff, false}, /* 0x229c */
 	{RCS, GEN9_CTX_PREEMPT_REG, 0x0, false}, /* 0x2248 */
 	{RCS, HWSTAM, 0x0, false}, /* 0x2098 */
 	{RCS, INSTPM, 0xffff, true}, /* 0x20c0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 0), 0, false}, /* 0x24d0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 1), 0, false}, /* 0x24d4 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 2), 0, false}, /* 0x24d8 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 3), 0, false}, /* 0x24dc */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 4), 0, false}, /* 0x24e0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 5), 0, false}, /* 0x24e4 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 6), 0, false}, /* 0x24e8 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 7), 0, false}, /* 0x24ec */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 8), 0, false}, /* 0x24f0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 9), 0, false}, /* 0x24f4 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 10), 0, false}, /* 0x24f8 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 11), 0, false}, /* 0x24fc */
 	{RCS, CACHE_MODE_1, 0xffff, true}, /* 0x7004 */
 	{RCS, GEN7_GT_MODE, 0xffff, true}, /* 0x7008 */
 	{RCS, CACHE_MODE_0_GEN7, 0xffff, true}, /* 0x7000 */
 	{RCS, GEN7_COMMON_SLICE_CHICKEN1, 0xffff, true}, /* 0x7010 */
 	{RCS, HDC_CHICKEN0, 0xffff, true}, /* 0x7300 */
 	{RCS, VF_GUARDBAND, 0xffff, true}, /* 0x83a4 */

 	{BCS, RING_GFX_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2229c */
 	{BCS, RING_MI_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2209c */
 	{BCS, RING_INSTPM(BLT_RING_BASE), 0xffff, false}, /* 0x220c0 */
 	{BCS, RING_HWSTAM(BLT_RING_BASE), 0x0, false}, /* 0x22098 */
 	{BCS, RING_EXCC(BLT_RING_BASE), 0x0, false}, /* 0x22028 */
 	{RCS, INVALID_MMIO_REG, 0, false } /* Terminated */
 };

 static struct engine_mmio gen9_engine_mmio_list[] __cacheline_aligned = {
 	{RCS, GFX_MODE_GEN7, 0xffff, false}, /* 0x229c */
 	{RCS, GEN9_CTX_PREEMPT_REG, 0x0, false}, /* 0x2248 */
 	{RCS, HWSTAM, 0x0, false}, /* 0x2098 */
 	{RCS, INSTPM, 0xffff, true}, /* 0x20c0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 0), 0, false}, /* 0x24d0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 1), 0, false}, /* 0x24d4 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 2), 0, false}, /* 0x24d8 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 3), 0, false}, /* 0x24dc */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 4), 0, false}, /* 0x24e0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 5), 0, false}, /* 0x24e4 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 6), 0, false}, /* 0x24e8 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 7), 0, false}, /* 0x24ec */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 8), 0, false}, /* 0x24f0 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 9), 0, false}, /* 0x24f4 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 10), 0, false}, /* 0x24f8 */
 	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 11), 0, false}, /* 0x24fc */
 	{RCS, CACHE_MODE_1, 0xffff, true}, /* 0x7004 */
 	{RCS, GEN7_GT_MODE, 0xffff, true}, /* 0x7008 */
 	{RCS, CACHE_MODE_0_GEN7, 0xffff, true}, /* 0x7000 */
 	{RCS, GEN7_COMMON_SLICE_CHICKEN1, 0xffff, true}, /* 0x7010 */
 	{RCS, HDC_CHICKEN0, 0xffff, true}, /* 0x7300 */
 	{RCS, VF_GUARDBAND, 0xffff, true}, /* 0x83a4 */

 	{RCS, GEN8_PRIVATE_PAT_LO, 0, false}, /* 0x40e0 */
 	{RCS, GEN8_PRIVATE_PAT_HI, 0, false}, /* 0x40e4 */
 	{RCS, GEN8_CS_CHICKEN1, 0xffff, true}, /* 0x2580 */
 	{RCS, COMMON_SLICE_CHICKEN2, 0xffff, true}, /* 0x7014 */
 	{RCS, GEN9_CS_DEBUG_MODE1, 0xffff, false}, /* 0x20ec */
 	{RCS, GEN8_L3SQCREG4, 0, false}, /* 0xb118 */
 	{RCS, GEN7_HALF_SLICE_CHICKEN1, 0xffff, true}, /* 0xe100 */
 	{RCS, HALF_SLICE_CHICKEN2, 0xffff, true}, /* 0xe180 */
 	{RCS, HALF_SLICE_CHICKEN3, 0xffff, true}, /* 0xe184 */
 	{RCS, GEN9_HALF_SLICE_CHICKEN5, 0xffff, true}, /* 0xe188 */
 	{RCS, GEN9_HALF_SLICE_CHICKEN7, 0xffff, true}, /* 0xe194 */
 	{RCS, GEN8_ROW_CHICKEN, 0xffff, true}, /* 0xe4f0 */
 	{RCS, TRVATTL3PTRDW(0), 0, false}, /* 0x4de0 */
 	{RCS, TRVATTL3PTRDW(1), 0, false}, /* 0x4de4 */
 	{RCS, TRNULLDETCT, 0, false}, /* 0x4de8 */
 	{RCS, TRINVTILEDETCT, 0, false}, /* 0x4dec */
 	{RCS, TRVADR, 0, false}, /* 0x4df0 */
 	{RCS, TRTTE, 0, false}, /* 0x4df4 */

 	{BCS, RING_GFX_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2229c */
 	{BCS, RING_MI_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2209c */
 	{BCS, RING_INSTPM(BLT_RING_BASE), 0xffff, false}, /* 0x220c0 */
 	{BCS, RING_HWSTAM(BLT_RING_BASE), 0x0, false}, /* 0x22098 */
 	{BCS, RING_EXCC(BLT_RING_BASE), 0x0, false}, /* 0x22028 */

 	{VCS2, RING_EXCC(GEN8_BSD2_RING_BASE), 0xffff, false}, /* 0x1c028 */

 	{VECS, RING_EXCC(VEBOX_RING_BASE), 0xffff, false}, /* 0x1a028 */

 	{RCS, GEN8_HDC_CHICKEN1, 0xffff, true}, /* 0x7304 */
 	{RCS, GEN9_CTX_PREEMPT_REG, 0x0, false}, /* 0x2248 */
 	{RCS, GEN7_UCGCTL4, 0x0, false}, /* 0x940c */
 	{RCS, GAMT_CHKN_BIT_REG, 0x0, false}, /* 0x4ab8 */

 	{RCS, GEN9_GAMT_ECO_REG_RW_IA, 0x0, false}, /* 0x4ab0 */
 	{RCS, GEN9_CSFE_CHICKEN1_RCS, 0xffff, false}, /* 0x20d4 */

 	{RCS, GEN8_GARBCNTL, 0x0, false}, /* 0xb004 */
 	{RCS, GEN7_FF_THREAD_MODE, 0x0, false}, /* 0x20a0 */
 	{RCS, FF_SLICE_CS_CHICKEN2, 0xffff, false}, /* 0x20e4 */
 	{RCS, INVALID_MMIO_REG, 0, false } /* Terminated */
 };

 static struct {
 	bool initialized;
 	u32 control_table[I915_NUM_ENGINES][GEN9_MOCS_SIZE];
 	u32 l3cc_table[GEN9_MOCS_SIZE / 2];
 } gen9_render_mocs;

 static void load_render_mocs(struct drm_i915_private *dev_priv)
 {
 	i915_reg_t offset;
 	u32 regs[] = {
 		[RCS] = 0xc800,
 		[VCS] = 0xc900,
 		[VCS2] = 0xca00,
 		[BCS] = 0xcc00,
 		[VECS] = 0xcb00,
 	};
 	int ring_id, i;

 	for (ring_id = 0; ring_id < ARRAY_SIZE(regs); ring_id++) {
 		if (!HAS_ENGINE(dev_priv, ring_id))
 			continue;
 		offset.reg = regs[ring_id];
 		for (i = 0; i < GEN9_MOCS_SIZE; i++) {
 			gen9_render_mocs.control_table[ring_id][i] =
 				I915_READ_FW(offset);
 			offset.reg += 4;
 		}
 	}

 	offset.reg = 0xb020;
 	for (i = 0; i < GEN9_MOCS_SIZE / 2; i++) {
 		gen9_render_mocs.l3cc_table[i] =
 			I915_READ_FW(offset);
 		offset.reg += 4;
 	}
 	gen9_render_mocs.initialized = true;
 }

 static int
 restore_context_mmio_for_inhibit(struct intel_vgpu *vgpu,
 				 struct i915_request *req)
 {
 	u32 *cs;
 	int ret;
 	struct engine_mmio *mmio;
 	struct intel_gvt *gvt = vgpu->gvt;
 	int ring_id = req->engine->id;
 	int count = gvt->engine_mmio_list.ctx_mmio_count[ring_id];

 	if (count == 0)
 		return 0;

 	ret = req->engine->emit_flush(req, EMIT_BARRIER);
 	if (ret)
 		return ret;

 	cs = intel_ring_begin(req, count * 2 + 2);
 	if (IS_ERR(cs))
 		return PTR_ERR(cs);

 	*cs++ = MI_LOAD_REGISTER_IMM(count);
 	for (mmio = gvt->engine_mmio_list.mmio;
 	     i915_mmio_reg_valid(mmio->reg); mmio++) {
 		if (mmio->ring_id != ring_id ||
 		    !mmio->in_context)
 			continue;

 		*cs++ = i915_mmio_reg_offset(mmio->reg);
 		*cs++ = vgpu_vreg_t(vgpu, mmio->reg) |
 				(mmio->mask << 16);
 		gvt_dbg_core("add lri reg pair 0x%x:0x%x in inhibit ctx, vgpu:%d, rind_id:%d\n",
 			      *(cs-2), *(cs-1), vgpu->id, ring_id);
 	}

 	*cs++ = MI_NOOP;
 	intel_ring_advance(req, cs);

 	ret = req->engine->emit_flush(req, EMIT_BARRIER);
 	if (ret)
 		return ret;

 	return 0;
 }

 static int
 restore_render_mocs_control_for_inhibit(struct intel_vgpu *vgpu,
 					struct i915_request *req)
 {
 	unsigned int index;
 	u32 *cs;

 	cs = intel_ring_begin(req, 2 * GEN9_MOCS_SIZE + 2);
 	if (IS_ERR(cs))
 		return PTR_ERR(cs);

 	*cs++ = MI_LOAD_REGISTER_IMM(GEN9_MOCS_SIZE);

 	for (index = 0; index < GEN9_MOCS_SIZE; index++) {
 		*cs++ = i915_mmio_reg_offset(GEN9_GFX_MOCS(index));
 		*cs++ = vgpu_vreg_t(vgpu, GEN9_GFX_MOCS(index));
 		gvt_dbg_core("add lri reg pair 0x%x:0x%x in inhibit ctx, vgpu:%d, rind_id:%d\n",
 			      *(cs-2), *(cs-1), vgpu->id, req->engine->id);

 	}

 	*cs++ = MI_NOOP;
 	intel_ring_advance(req, cs);

 	return 0;
 }

 static int
 restore_render_mocs_l3cc_for_inhibit(struct intel_vgpu *vgpu,
 				     struct i915_request *req)
 {
 	unsigned int index;
 	u32 *cs;

 	cs = intel_ring_begin(req, 2 * GEN9_MOCS_SIZE / 2 + 2);
 	if (IS_ERR(cs))
 		return PTR_ERR(cs);

 	*cs++ = MI_LOAD_REGISTER_IMM(GEN9_MOCS_SIZE / 2);

 	for (index = 0; index < GEN9_MOCS_SIZE / 2; index++) {
 		*cs++ = i915_mmio_reg_offset(GEN9_LNCFCMOCS(index));
 		*cs++ = vgpu_vreg_t(vgpu, GEN9_LNCFCMOCS(index));
 		gvt_dbg_core("add lri reg pair 0x%x:0x%x in inhibit ctx, vgpu:%d, rind_id:%d\n",
 			      *(cs-2), *(cs-1), vgpu->id, req->engine->id);

 	}

 	*cs++ = MI_NOOP;
 	intel_ring_advance(req, cs);

 	return 0;
 }

 /*
  * Use lri command to initialize the mmio which is in context state image for
  * inhibit context, it contains tracked engine mmio, render_mocs and
  * render_mocs_l3cc.
  */
 int intel_vgpu_restore_inhibit_context(struct intel_vgpu *vgpu,
 				       struct i915_request *req)
 {
 	int ret;
 	u32 *cs;

 	cs = intel_ring_begin(req, 2);
 	if (IS_ERR(cs))
 		return PTR_ERR(cs);

 	*cs++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
 	*cs++ = MI_NOOP;
 	intel_ring_advance(req, cs);

 	ret = restore_context_mmio_for_inhibit(vgpu, req);
 	if (ret)
 		goto out;

 	/* no MOCS register in context except render engine */
 	if (req->engine->id != RCS)
 		goto out;

 	ret = restore_render_mocs_control_for_inhibit(vgpu, req);
 	if (ret)
 		goto out;

 	ret = restore_render_mocs_l3cc_for_inhibit(vgpu, req);
 	if (ret)
 		goto out;

 out:
 	cs = intel_ring_begin(req, 2);
 	if (IS_ERR(cs))
 		return PTR_ERR(cs);

 	*cs++ = MI_ARB_ON_OFF | MI_ARB_ENABLE;
 	*cs++ = MI_NOOP;
 	intel_ring_advance(req, cs);

 	return ret;
 }

 static void handle_tlb_pending_event(struct intel_vgpu *vgpu, int ring_id)
 {
 	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
 	struct intel_vgpu_submission *s = &vgpu->submission;
 	enum forcewake_domains fw;
 	i915_reg_t reg;
 	u32 regs[] = {
 		[RCS] = 0x4260,
 		[VCS] = 0x4264,
 		[VCS2] = 0x4268,
 		[BCS] = 0x426c,
 		[VECS] = 0x4270,
 	};

 	if (WARN_ON(ring_id >= ARRAY_SIZE(regs)))
 		return;

 	if (!test_and_clear_bit(ring_id, (void *)s->tlb_handle_pending))
 		return;

 	reg = _MMIO(regs[ring_id]);

 	/* WaForceWakeRenderDuringMmioTLBInvalidate:skl
 	 * we need to put a forcewake when invalidating RCS TLB caches,
 	 * otherwise device can go to RC6 state and interrupt invalidation
 	 * process
 	 */
 	fw = intel_uncore_forcewake_for_reg(dev_priv, reg,
 					    FW_REG_READ | FW_REG_WRITE);
 	if (ring_id == RCS && (INTEL_GEN(dev_priv) >= 9))
 		fw |= FORCEWAKE_RENDER;

 	intel_uncore_forcewake_get(dev_priv, fw);

 	I915_WRITE_FW(reg, 0x1);

 	if (wait_for_atomic((I915_READ_FW(reg) == 0), 50))
 		gvt_vgpu_err("timeout in invalidate ring (%d) tlb\n", ring_id);
 	else
 		vgpu_vreg_t(vgpu, reg) = 0;

 	intel_uncore_forcewake_put(dev_priv, fw);

 	gvt_dbg_core("invalidate TLB for ring %d\n", ring_id);
 }

 static void switch_mocs(struct intel_vgpu *pre, struct intel_vgpu *next,
 			int ring_id)
 {
 	struct drm_i915_private *dev_priv;
 	i915_reg_t offset, l3_offset;
 	u32 old_v, new_v;

 	u32 regs[] = {
 		[RCS] = 0xc800,
 		[VCS] = 0xc900,
 		[VCS2] = 0xca00,
 		[BCS] = 0xcc00,
 		[VECS] = 0xcb00,
 	};
 	int i;

 	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;
 	if (WARN_ON(ring_id >= ARRAY_SIZE(regs)))
 		return;

 	if ((IS_KABYLAKE(dev_priv)  || IS_BROXTON(dev_priv)
 		|| IS_COFFEELAKE(dev_priv)) && ring_id == RCS)
 		return;

 	if (!pre && !gen9_render_mocs.initialized)
 		load_render_mocs(dev_priv);

 	offset.reg = regs[ring_id];
 	for (i = 0; i < GEN9_MOCS_SIZE; i++) {
 		if (pre)
 			old_v = vgpu_vreg_t(pre, offset);
 		else
 			old_v = gen9_render_mocs.control_table[ring_id][i];
 		if (next)
 			new_v = vgpu_vreg_t(next, offset);
 		else
 			new_v = gen9_render_mocs.control_table[ring_id][i];

 		if (old_v != new_v)
 			I915_WRITE_FW(offset, new_v);

 		offset.reg += 4;
 	}

 	if (ring_id == RCS) {
 		l3_offset.reg = 0xb020;
 		for (i = 0; i < GEN9_MOCS_SIZE / 2; i++) {
 			if (pre)
 				old_v = vgpu_vreg_t(pre, l3_offset);
 			else
 				old_v = gen9_render_mocs.l3cc_table[i];
 			if (next)
 				new_v = vgpu_vreg_t(next, l3_offset);
 			else
 				new_v = gen9_render_mocs.l3cc_table[i];

 			if (old_v != new_v)
 				I915_WRITE_FW(l3_offset, new_v);

 			l3_offset.reg += 4;
 		}
 	}
 }

 #define CTX_CONTEXT_CONTROL_VAL	0x03

 bool is_inhibit_context(struct intel_context *ce)
 {
 	const u32 *reg_state = ce->lrc_reg_state;
 	u32 inhibit_mask =
 		_MASKED_BIT_ENABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);

 	return inhibit_mask ==
 		(reg_state[CTX_CONTEXT_CONTROL_VAL] & inhibit_mask);
 }

 /* Switch ring mmio values (context). */
 static void switch_mmio(struct intel_vgpu *pre,
 			struct intel_vgpu *next,
 			int ring_id)
 {
 	struct drm_i915_private *dev_priv;
 	struct intel_vgpu_submission *s;
 	struct engine_mmio *mmio;
 	u32 old_v, new_v;

 	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;
 	if (INTEL_GEN(dev_priv) >= 9)
 		switch_mocs(pre, next, ring_id);

 	for (mmio = dev_priv->gvt->engine_mmio_list.mmio;
 	     i915_mmio_reg_valid(mmio->reg); mmio++) {
 		if (mmio->ring_id != ring_id)
 			continue;
 		/*
 		 * No need to do save or restore of the mmio which is in context
 		 * state image on kabylake, it's initialized by lri command and
 		 * save or restore with context together.
 		 */
 		if ((IS_KABYLAKE(dev_priv) || IS_BROXTON(dev_priv)
 			|| IS_COFFEELAKE(dev_priv)) && mmio->in_context)
 			continue;

 		// save
 		if (pre) {
 			vgpu_vreg_t(pre, mmio->reg) = I915_READ_FW(mmio->reg);
 			if (mmio->mask)
 				vgpu_vreg_t(pre, mmio->reg) &=
 						~(mmio->mask << 16);
 			old_v = vgpu_vreg_t(pre, mmio->reg);
 		} else
 			old_v = mmio->value = I915_READ_FW(mmio->reg);

 		// restore
 		if (next) {
 			s = &next->submission;
 			/*
 			 * No need to restore the mmio which is in context state
 			 * image if it's not inhibit context, it will restore
 			 * itself.
 			 */
 			if (mmio->in_context &&
 			    !is_inhibit_context(&s->shadow_ctx->__engine[ring_id]))
 				continue;

 			if (mmio->mask)
 				new_v = vgpu_vreg_t(next, mmio->reg) |
 							(mmio->mask << 16);
 			else
 				new_v = vgpu_vreg_t(next, mmio->reg);
 		} else {
 			if (mmio->in_context)
 				continue;
 			if (mmio->mask)
 				new_v = mmio->value | (mmio->mask << 16);
 			else
 				new_v = mmio->value;
 		}

 		I915_WRITE_FW(mmio->reg, new_v);

 		trace_render_mmio(pre ? pre->id : 0,
 				  next ? next->id : 0,
 				  "switch",
 				  i915_mmio_reg_offset(mmio->reg),
 				  old_v, new_v);
 	}

 	if (next)
 		handle_tlb_pending_event(next, ring_id);
 }

 /**
  * intel_gvt_switch_render_mmio - switch mmio context of specific engine
  * @pre: the last vGPU that own the engine
  * @next: the vGPU to switch to
  * @ring_id: specify the engine
  *
  * If pre is null indicates that host own the engine. If next is null
  * indicates that we are switching to host workload.
  */
 void intel_gvt_switch_mmio(struct intel_vgpu *pre,
 			   struct intel_vgpu *next, int ring_id)
 {
 	struct drm_i915_private *dev_priv;

 	if (WARN_ON(!pre && !next))
 		return;

 	gvt_dbg_render("switch ring %d from %s to %s\n", ring_id,
 		       pre ? "vGPU" : "host", next ? "vGPU" : "HOST");

 	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;

 	/**
 	 * We are using raw mmio access wrapper to improve the
 	 * performace for batch mmio read/write, so we need
 	 * handle forcewake mannually.
 	 */
 	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
 	switch_mmio(pre, next, ring_id);
 	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
 }

 /**
  * intel_gvt_init_engine_mmio_context - Initiate the engine mmio list
  * @gvt: GVT device
  *
  */
 void intel_gvt_init_engine_mmio_context(struct intel_gvt *gvt)
 {
 	struct engine_mmio *mmio;

 	if (INTEL_GEN(gvt->dev_priv) >= 9)
 		gvt->engine_mmio_list.mmio = gen9_engine_mmio_list;
 	else
 		gvt->engine_mmio_list.mmio = gen8_engine_mmio_list;

 	for (mmio = gvt->engine_mmio_list.mmio;
 	     i915_mmio_reg_valid(mmio->reg); mmio++) {
 		if (mmio->in_context) {
 			gvt->engine_mmio_list.ctx_mmio_count[mmio->ring_id]++;
 			intel_gvt_mmio_set_in_ctx(gvt, mmio->reg.reg);
 		}
 	}
 }
	/*
	* Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, 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:
	* Eddie Dong <eddie.dong@intel.com>
	* Kevin Tian <kevin.tian@intel.com>
	*
	* Contributors:
	* Zhi Wang <zhi.a.wang@intel.com>
	* Changbin Du <changbin.du@intel.com>
	* Zhenyu Wang <zhenyuw@linux.intel.com>
	* Tina Zhang <tina.zhang@intel.com>
	* Bing Niu <bing.niu@intel.com>
	*
	*/

	#include "i915_drv.h"
	#include "gvt.h"
	#include "trace.h"

	#define GEN9_MOCS_SIZE 64

	/* Raw offset is appened to each line for convenience. */
	static struct engine_mmio gen8_engine_mmio_list[] __cacheline_aligned = {
	{RCS, GFX_MODE_GEN7, 0xffff, false}, /* 0x229c */
	{RCS, GEN9_CTX_PREEMPT_REG, 0x0, false}, /* 0x2248 */
	{RCS, HWSTAM, 0x0, false}, /* 0x2098 */
	{RCS, INSTPM, 0xffff, true}, /* 0x20c0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 0), 0, false}, /* 0x24d0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 1), 0, false}, /* 0x24d4 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 2), 0, false}, /* 0x24d8 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 3), 0, false}, /* 0x24dc */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 4), 0, false}, /* 0x24e0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 5), 0, false}, /* 0x24e4 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 6), 0, false}, /* 0x24e8 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 7), 0, false}, /* 0x24ec */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 8), 0, false}, /* 0x24f0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 9), 0, false}, /* 0x24f4 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 10), 0, false}, /* 0x24f8 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 11), 0, false}, /* 0x24fc */
	{RCS, CACHE_MODE_1, 0xffff, true}, /* 0x7004 */
	{RCS, GEN7_GT_MODE, 0xffff, true}, /* 0x7008 */
	{RCS, CACHE_MODE_0_GEN7, 0xffff, true}, /* 0x7000 */
	{RCS, GEN7_COMMON_SLICE_CHICKEN1, 0xffff, true}, /* 0x7010 */
	{RCS, HDC_CHICKEN0, 0xffff, true}, /* 0x7300 */
	{RCS, VF_GUARDBAND, 0xffff, true}, /* 0x83a4 */

	{BCS, RING_GFX_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2229c */
	{BCS, RING_MI_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2209c */
	{BCS, RING_INSTPM(BLT_RING_BASE), 0xffff, false}, /* 0x220c0 */
	{BCS, RING_HWSTAM(BLT_RING_BASE), 0x0, false}, /* 0x22098 */
	{BCS, RING_EXCC(BLT_RING_BASE), 0x0, false}, /* 0x22028 */
	{RCS, INVALID_MMIO_REG, 0, false } /* Terminated */
	};

	static struct engine_mmio gen9_engine_mmio_list[] __cacheline_aligned = {
	{RCS, GFX_MODE_GEN7, 0xffff, false}, /* 0x229c */
	{RCS, GEN9_CTX_PREEMPT_REG, 0x0, false}, /* 0x2248 */
	{RCS, HWSTAM, 0x0, false}, /* 0x2098 */
	{RCS, INSTPM, 0xffff, true}, /* 0x20c0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 0), 0, false}, /* 0x24d0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 1), 0, false}, /* 0x24d4 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 2), 0, false}, /* 0x24d8 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 3), 0, false}, /* 0x24dc */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 4), 0, false}, /* 0x24e0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 5), 0, false}, /* 0x24e4 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 6), 0, false}, /* 0x24e8 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 7), 0, false}, /* 0x24ec */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 8), 0, false}, /* 0x24f0 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 9), 0, false}, /* 0x24f4 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 10), 0, false}, /* 0x24f8 */
	{RCS, RING_FORCE_TO_NONPRIV(RENDER_RING_BASE, 11), 0, false}, /* 0x24fc */
	{RCS, CACHE_MODE_1, 0xffff, true}, /* 0x7004 */
	{RCS, GEN7_GT_MODE, 0xffff, true}, /* 0x7008 */
	{RCS, CACHE_MODE_0_GEN7, 0xffff, true}, /* 0x7000 */
	{RCS, GEN7_COMMON_SLICE_CHICKEN1, 0xffff, true}, /* 0x7010 */
	{RCS, HDC_CHICKEN0, 0xffff, true}, /* 0x7300 */
	{RCS, VF_GUARDBAND, 0xffff, true}, /* 0x83a4 */

	{RCS, GEN8_PRIVATE_PAT_LO, 0, false}, /* 0x40e0 */
	{RCS, GEN8_PRIVATE_PAT_HI, 0, false}, /* 0x40e4 */
	{RCS, GEN8_CS_CHICKEN1, 0xffff, true}, /* 0x2580 */
	{RCS, COMMON_SLICE_CHICKEN2, 0xffff, true}, /* 0x7014 */
	{RCS, GEN9_CS_DEBUG_MODE1, 0xffff, false}, /* 0x20ec */
	{RCS, GEN8_L3SQCREG4, 0, false}, /* 0xb118 */
	{RCS, GEN7_HALF_SLICE_CHICKEN1, 0xffff, true}, /* 0xe100 */
	{RCS, HALF_SLICE_CHICKEN2, 0xffff, true}, /* 0xe180 */
	{RCS, HALF_SLICE_CHICKEN3, 0xffff, true}, /* 0xe184 */
	{RCS, GEN9_HALF_SLICE_CHICKEN5, 0xffff, true}, /* 0xe188 */
	{RCS, GEN9_HALF_SLICE_CHICKEN7, 0xffff, true}, /* 0xe194 */
	{RCS, GEN8_ROW_CHICKEN, 0xffff, true}, /* 0xe4f0 */
	{RCS, TRVATTL3PTRDW(0), 0, false}, /* 0x4de0 */
	{RCS, TRVATTL3PTRDW(1), 0, false}, /* 0x4de4 */
	{RCS, TRNULLDETCT, 0, false}, /* 0x4de8 */
	{RCS, TRINVTILEDETCT, 0, false}, /* 0x4dec */
	{RCS, TRVADR, 0, false}, /* 0x4df0 */
	{RCS, TRTTE, 0, false}, /* 0x4df4 */

	{BCS, RING_GFX_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2229c */
	{BCS, RING_MI_MODE(BLT_RING_BASE), 0xffff, false}, /* 0x2209c */
	{BCS, RING_INSTPM(BLT_RING_BASE), 0xffff, false}, /* 0x220c0 */
	{BCS, RING_HWSTAM(BLT_RING_BASE), 0x0, false}, /* 0x22098 */
	{BCS, RING_EXCC(BLT_RING_BASE), 0x0, false}, /* 0x22028 */

	{VCS2, RING_EXCC(GEN8_BSD2_RING_BASE), 0xffff, false}, /* 0x1c028 */

	{VECS, RING_EXCC(VEBOX_RING_BASE), 0xffff, false}, /* 0x1a028 */

	{RCS, GEN8_HDC_CHICKEN1, 0xffff, true}, /* 0x7304 */
	{RCS, GEN9_CTX_PREEMPT_REG, 0x0, false}, /* 0x2248 */
	{RCS, GEN7_UCGCTL4, 0x0, false}, /* 0x940c */
	{RCS, GAMT_CHKN_BIT_REG, 0x0, false}, /* 0x4ab8 */

	{RCS, GEN9_GAMT_ECO_REG_RW_IA, 0x0, false}, /* 0x4ab0 */
	{RCS, GEN9_CSFE_CHICKEN1_RCS, 0xffff, false}, /* 0x20d4 */

	{RCS, GEN8_GARBCNTL, 0x0, false}, /* 0xb004 */
	{RCS, GEN7_FF_THREAD_MODE, 0x0, false}, /* 0x20a0 */
	{RCS, FF_SLICE_CS_CHICKEN2, 0xffff, false}, /* 0x20e4 */
	{RCS, INVALID_MMIO_REG, 0, false } /* Terminated */
	};

	static struct {
	bool initialized;
	u32 control_table[I915_NUM_ENGINES][GEN9_MOCS_SIZE];
	u32 l3cc_table[GEN9_MOCS_SIZE / 2];
	} gen9_render_mocs;

	static void load_render_mocs(struct drm_i915_private *dev_priv)
	{
	i915_reg_t offset;
	u32 regs[] = {
	[RCS] = 0xc800,
	[VCS] = 0xc900,
	[VCS2] = 0xca00,
	[BCS] = 0xcc00,
	[VECS] = 0xcb00,
	};
	int ring_id, i;

	for (ring_id = 0; ring_id < ARRAY_SIZE(regs); ring_id++) {
	if (!HAS_ENGINE(dev_priv, ring_id))
	continue;
	offset.reg = regs[ring_id];
	for (i = 0; i < GEN9_MOCS_SIZE; i++) {
	gen9_render_mocs.control_table[ring_id][i] =
	I915_READ_FW(offset);
	offset.reg += 4;
	}
	}

	offset.reg = 0xb020;
	for (i = 0; i < GEN9_MOCS_SIZE / 2; i++) {
	gen9_render_mocs.l3cc_table[i] =
	I915_READ_FW(offset);
	offset.reg += 4;
	}
	gen9_render_mocs.initialized = true;
	}

	static int
	restore_context_mmio_for_inhibit(struct intel_vgpu *vgpu,
	struct i915_request *req)
	{
	u32 *cs;
	int ret;
	struct engine_mmio *mmio;
	struct intel_gvt *gvt = vgpu->gvt;
	int ring_id = req->engine->id;
	int count = gvt->engine_mmio_list.ctx_mmio_count[ring_id];

	if (count == 0)
	return 0;

	ret = req->engine->emit_flush(req, EMIT_BARRIER);
	if (ret)
	return ret;

	cs = intel_ring_begin(req, count * 2 + 2);
	if (IS_ERR(cs))
	return PTR_ERR(cs);

	*cs++ = MI_LOAD_REGISTER_IMM(count);
	for (mmio = gvt->engine_mmio_list.mmio;
	i915_mmio_reg_valid(mmio->reg); mmio++) {
	if (mmio->ring_id != ring_id \|\|
	!mmio->in_context)
	continue;

	*cs++ = i915_mmio_reg_offset(mmio->reg);
	*cs++ = vgpu_vreg_t(vgpu, mmio->reg) \|
	(mmio->mask << 16);
	gvt_dbg_core("add lri reg pair 0x%x:0x%x in inhibit ctx, vgpu:%d, rind_id:%d\n",
	(cs-2), (cs-1), vgpu->id, ring_id);
	}

	*cs++ = MI_NOOP;
	intel_ring_advance(req, cs);

	ret = req->engine->emit_flush(req, EMIT_BARRIER);
	if (ret)
	return ret;

	return 0;
	}

	static int
	restore_render_mocs_control_for_inhibit(struct intel_vgpu *vgpu,
	struct i915_request *req)
	{
	unsigned int index;
	u32 *cs;

	cs = intel_ring_begin(req, 2 * GEN9_MOCS_SIZE + 2);
	if (IS_ERR(cs))
	return PTR_ERR(cs);

	*cs++ = MI_LOAD_REGISTER_IMM(GEN9_MOCS_SIZE);

	for (index = 0; index < GEN9_MOCS_SIZE; index++) {
	*cs++ = i915_mmio_reg_offset(GEN9_GFX_MOCS(index));
	*cs++ = vgpu_vreg_t(vgpu, GEN9_GFX_MOCS(index));
	gvt_dbg_core("add lri reg pair 0x%x:0x%x in inhibit ctx, vgpu:%d, rind_id:%d\n",
	(cs-2), (cs-1), vgpu->id, req->engine->id);

	}

	*cs++ = MI_NOOP;
	intel_ring_advance(req, cs);

	return 0;
	}

	static int
	restore_render_mocs_l3cc_for_inhibit(struct intel_vgpu *vgpu,
	struct i915_request *req)
	{
	unsigned int index;
	u32 *cs;

	cs = intel_ring_begin(req, 2 * GEN9_MOCS_SIZE / 2 + 2);
	if (IS_ERR(cs))
	return PTR_ERR(cs);

	*cs++ = MI_LOAD_REGISTER_IMM(GEN9_MOCS_SIZE / 2);

	for (index = 0; index < GEN9_MOCS_SIZE / 2; index++) {
	*cs++ = i915_mmio_reg_offset(GEN9_LNCFCMOCS(index));
	*cs++ = vgpu_vreg_t(vgpu, GEN9_LNCFCMOCS(index));
	gvt_dbg_core("add lri reg pair 0x%x:0x%x in inhibit ctx, vgpu:%d, rind_id:%d\n",
	(cs-2), (cs-1), vgpu->id, req->engine->id);

	}

	*cs++ = MI_NOOP;
	intel_ring_advance(req, cs);

	return 0;
	}

	/*
	* Use lri command to initialize the mmio which is in context state image for
	* inhibit context, it contains tracked engine mmio, render_mocs and
	* render_mocs_l3cc.
	*/
	int intel_vgpu_restore_inhibit_context(struct intel_vgpu *vgpu,
	struct i915_request *req)
	{
	int ret;
	u32 *cs;

	cs = intel_ring_begin(req, 2);
	if (IS_ERR(cs))
	return PTR_ERR(cs);

	*cs++ = MI_ARB_ON_OFF \| MI_ARB_DISABLE;
	*cs++ = MI_NOOP;
	intel_ring_advance(req, cs);

	ret = restore_context_mmio_for_inhibit(vgpu, req);
	if (ret)
	goto out;

	/* no MOCS register in context except render engine */
	if (req->engine->id != RCS)
	goto out;

	ret = restore_render_mocs_control_for_inhibit(vgpu, req);
	if (ret)
	goto out;

	ret = restore_render_mocs_l3cc_for_inhibit(vgpu, req);
	if (ret)
	goto out;

	out:
	cs = intel_ring_begin(req, 2);
	if (IS_ERR(cs))
	return PTR_ERR(cs);

	*cs++ = MI_ARB_ON_OFF \| MI_ARB_ENABLE;
	*cs++ = MI_NOOP;
	intel_ring_advance(req, cs);

	return ret;
	}

	static void handle_tlb_pending_event(struct intel_vgpu *vgpu, int ring_id)
	{
	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
	struct intel_vgpu_submission *s = &vgpu->submission;
	enum forcewake_domains fw;
	i915_reg_t reg;
	u32 regs[] = {
	[RCS] = 0x4260,
	[VCS] = 0x4264,
	[VCS2] = 0x4268,
	[BCS] = 0x426c,
	[VECS] = 0x4270,
	};

	if (WARN_ON(ring_id >= ARRAY_SIZE(regs)))
	return;

	if (!test_and_clear_bit(ring_id, (void *)s->tlb_handle_pending))
	return;

	reg = _MMIO(regs[ring_id]);

	/* WaForceWakeRenderDuringMmioTLBInvalidate:skl
	* we need to put a forcewake when invalidating RCS TLB caches,
	* otherwise device can go to RC6 state and interrupt invalidation
	* process
	*/
	fw = intel_uncore_forcewake_for_reg(dev_priv, reg,
	FW_REG_READ \| FW_REG_WRITE);
	if (ring_id == RCS && (INTEL_GEN(dev_priv) >= 9))
	fw \|= FORCEWAKE_RENDER;

	intel_uncore_forcewake_get(dev_priv, fw);

	I915_WRITE_FW(reg, 0x1);

	if (wait_for_atomic((I915_READ_FW(reg) == 0), 50))
	gvt_vgpu_err("timeout in invalidate ring (%d) tlb\n", ring_id);
	else
	vgpu_vreg_t(vgpu, reg) = 0;

	intel_uncore_forcewake_put(dev_priv, fw);

	gvt_dbg_core("invalidate TLB for ring %d\n", ring_id);
	}

	static void switch_mocs(struct intel_vgpu pre, struct intel_vgpu next,
	int ring_id)
	{
	struct drm_i915_private *dev_priv;
	i915_reg_t offset, l3_offset;
	u32 old_v, new_v;

	u32 regs[] = {
	[RCS] = 0xc800,
	[VCS] = 0xc900,
	[VCS2] = 0xca00,
	[BCS] = 0xcc00,
	[VECS] = 0xcb00,
	};
	int i;

	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;
	if (WARN_ON(ring_id >= ARRAY_SIZE(regs)))
	return;

	if ((IS_KABYLAKE(dev_priv) \|\| IS_BROXTON(dev_priv)
	\|\| IS_COFFEELAKE(dev_priv)) && ring_id == RCS)
	return;

	if (!pre && !gen9_render_mocs.initialized)
	load_render_mocs(dev_priv);

	offset.reg = regs[ring_id];
	for (i = 0; i < GEN9_MOCS_SIZE; i++) {
	if (pre)
	old_v = vgpu_vreg_t(pre, offset);
	else
	old_v = gen9_render_mocs.control_table[ring_id][i];
	if (next)
	new_v = vgpu_vreg_t(next, offset);
	else
	new_v = gen9_render_mocs.control_table[ring_id][i];

	if (old_v != new_v)
	I915_WRITE_FW(offset, new_v);

	offset.reg += 4;
	}

	if (ring_id == RCS) {
	l3_offset.reg = 0xb020;
	for (i = 0; i < GEN9_MOCS_SIZE / 2; i++) {
	if (pre)
	old_v = vgpu_vreg_t(pre, l3_offset);
	else
	old_v = gen9_render_mocs.l3cc_table[i];
	if (next)
	new_v = vgpu_vreg_t(next, l3_offset);
	else
	new_v = gen9_render_mocs.l3cc_table[i];

	if (old_v != new_v)
	I915_WRITE_FW(l3_offset, new_v);

	l3_offset.reg += 4;
	}
	}
	}

	#define CTX_CONTEXT_CONTROL_VAL 0x03

	bool is_inhibit_context(struct intel_context *ce)
	{
	const u32 *reg_state = ce->lrc_reg_state;
	u32 inhibit_mask =
	_MASKED_BIT_ENABLE(CTX_CTRL_ENGINE_CTX_RESTORE_INHIBIT);

	return inhibit_mask ==
	(reg_state[CTX_CONTEXT_CONTROL_VAL] & inhibit_mask);
	}

	/* Switch ring mmio values (context). */
	static void switch_mmio(struct intel_vgpu *pre,
	struct intel_vgpu *next,
	int ring_id)
	{
	struct drm_i915_private *dev_priv;
	struct intel_vgpu_submission *s;
	struct engine_mmio *mmio;
	u32 old_v, new_v;

	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;
	if (INTEL_GEN(dev_priv) >= 9)
	switch_mocs(pre, next, ring_id);

	for (mmio = dev_priv->gvt->engine_mmio_list.mmio;
	i915_mmio_reg_valid(mmio->reg); mmio++) {
	if (mmio->ring_id != ring_id)
	continue;
	/*
	* No need to do save or restore of the mmio which is in context
	* state image on kabylake, it's initialized by lri command and
	* save or restore with context together.
	*/
	if ((IS_KABYLAKE(dev_priv) \|\| IS_BROXTON(dev_priv)
	\|\| IS_COFFEELAKE(dev_priv)) && mmio->in_context)
	continue;

	// save
	if (pre) {
	vgpu_vreg_t(pre, mmio->reg) = I915_READ_FW(mmio->reg);
	if (mmio->mask)
	vgpu_vreg_t(pre, mmio->reg) &=
	~(mmio->mask << 16);
	old_v = vgpu_vreg_t(pre, mmio->reg);
	} else
	old_v = mmio->value = I915_READ_FW(mmio->reg);

	// restore
	if (next) {
	s = &next->submission;
	/*
	* No need to restore the mmio which is in context state
	* image if it's not inhibit context, it will restore
	* itself.
	*/
	if (mmio->in_context &&
	!is_inhibit_context(&s->shadow_ctx->__engine[ring_id]))
	continue;

	if (mmio->mask)
	new_v = vgpu_vreg_t(next, mmio->reg) \|
	(mmio->mask << 16);
	else
	new_v = vgpu_vreg_t(next, mmio->reg);
	} else {
	if (mmio->in_context)
	continue;
	if (mmio->mask)
	new_v = mmio->value \| (mmio->mask << 16);
	else
	new_v = mmio->value;
	}

	I915_WRITE_FW(mmio->reg, new_v);

	trace_render_mmio(pre ? pre->id : 0,
	next ? next->id : 0,
	"switch",
	i915_mmio_reg_offset(mmio->reg),
	old_v, new_v);
	}

	if (next)
	handle_tlb_pending_event(next, ring_id);
	}

	/**
	* intel_gvt_switch_render_mmio - switch mmio context of specific engine
	* @pre: the last vGPU that own the engine
	* @next: the vGPU to switch to
	* @ring_id: specify the engine
	*
	* If pre is null indicates that host own the engine. If next is null
	* indicates that we are switching to host workload.
	*/
	void intel_gvt_switch_mmio(struct intel_vgpu *pre,
	struct intel_vgpu *next, int ring_id)
	{
	struct drm_i915_private *dev_priv;

	if (WARN_ON(!pre && !next))
	return;

	gvt_dbg_render("switch ring %d from %s to %s\n", ring_id,
	pre ? "vGPU" : "host", next ? "vGPU" : "HOST");

	dev_priv = pre ? pre->gvt->dev_priv : next->gvt->dev_priv;

	/**
	* We are using raw mmio access wrapper to improve the
	* performace for batch mmio read/write, so we need
	* handle forcewake mannually.
	*/
	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
	switch_mmio(pre, next, ring_id);
	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
	}

	/**
	* intel_gvt_init_engine_mmio_context - Initiate the engine mmio list
	* @gvt: GVT device
	*
	*/
	void intel_gvt_init_engine_mmio_context(struct intel_gvt *gvt)
	{
	struct engine_mmio *mmio;

	if (INTEL_GEN(gvt->dev_priv) >= 9)
	gvt->engine_mmio_list.mmio = gen9_engine_mmio_list;
	else
	gvt->engine_mmio_list.mmio = gen8_engine_mmio_list;

	for (mmio = gvt->engine_mmio_list.mmio;
	i915_mmio_reg_valid(mmio->reg); mmio++) {
	if (mmio->in_context) {
	gvt->engine_mmio_list.ctx_mmio_count[mmio->ring_id]++;
	intel_gvt_mmio_set_in_ctx(gvt, mmio->reg.reg);
	}
	}
	}