drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+

This driver will be used to support Mesa on the Broadcom 7268 and 7278
platforms.

V3D 3.3 introduces an MMU, which means we no longer need CMA or vc4's
complicated CL/shader validation scheme.  This massively changes the
GEM behavior, so I've forked off to a new driver.

v2: Mark SUBMIT_CL as needing DRM_AUTH.  coccinelle fixes from kbuild
    test robot. Drop personal git link from MAINTAINERS.  Don't
    double-map dma-buf imported BOs.  Add kerneldoc about needing MMU
    eviction.  Drop prime vmap/unmap stubs.  Delay mmap offset setup
    to mmap time.  Use drm_dev_init instead of _alloc.  Use
    ktime_get() for wait_bo timeouts.  Drop drm_can_sleep() usage,
    since we don't modeset.  Switch page tables back to WC (debug
    change to coherent had slipped in).  Switch
    drm_gem_object_unreference_unlocked() to
    drm_gem_object_put_unlocked().  Simplify overflow mem handling by
    not sharing overflow mem between jobs.
v3: no changes
v4: align submit_cl to 64 bits (review by airlied), check zero flags in
    other ioctls.

Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v4)
Acked-by: Dave Airlie <airlied@linux.ie> (v3, requested submit_cl change)
Link: https://patchwork.freedesktop.org/patch/msgid/20180430181058.30181-3-eric@anholt.net

1 files changed, 668 insertions, 0 deletions

diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
new file mode 100644
index 000000000000..b513f9189caf
--- /dev/null
+++ b/drivers/gpu/drm/v3d/v3d_gem.c
@@ -0,0 +1,668 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (C) 2014-2018 Broadcom */
+
+#include <drm/drmP.h>
+#include <drm/drm_syncobj.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/sched/signal.h>
+
+#include "uapi/drm/v3d_drm.h"
+#include "v3d_drv.h"
+#include "v3d_regs.h"
+#include "v3d_trace.h"
+
+static void
+v3d_init_core(struct v3d_dev *v3d, int core)
+{
+	/* Set OVRTMUOUT, which means that the texture sampler uniform
+	 * configuration's tmu output type field is used, instead of
+	 * using the hardware default behavior based on the texture
+	 * type.  If you want the default behavior, you can still put
+	 * "2" in the indirect texture state's output_type field.
+	 */
+	V3D_CORE_WRITE(core, V3D_CTL_MISCCFG, V3D_MISCCFG_OVRTMUOUT);
+
+	/* Whenever we flush the L2T cache, we always want to flush
+	 * the whole thing.
+	 */
+	V3D_CORE_WRITE(core, V3D_CTL_L2TFLSTA, 0);
+	V3D_CORE_WRITE(core, V3D_CTL_L2TFLEND, ~0);
+}
+
+/* Sets invariant state for the HW. */
+static void
+v3d_init_hw_state(struct v3d_dev *v3d)
+{
+	v3d_init_core(v3d, 0);
+}
+
+static void
+v3d_idle_axi(struct v3d_dev *v3d, int core)
+{
+	V3D_CORE_WRITE(core, V3D_GMP_CFG, V3D_GMP_CFG_STOP_REQ);
+
+	if (wait_for((V3D_CORE_READ(core, V3D_GMP_STATUS) &
+		      (V3D_GMP_STATUS_RD_COUNT_MASK |
+		       V3D_GMP_STATUS_WR_COUNT_MASK |
+		       V3D_GMP_STATUS_CFG_BUSY)) == 0, 100)) {
+		DRM_ERROR("Failed to wait for safe GMP shutdown\n");
+	}
+}
+
+static void
+v3d_idle_gca(struct v3d_dev *v3d)
+{
+	if (v3d->ver >= 41)
+		return;
+
+	V3D_GCA_WRITE(V3D_GCA_SAFE_SHUTDOWN, V3D_GCA_SAFE_SHUTDOWN_EN);
+
+	if (wait_for((V3D_GCA_READ(V3D_GCA_SAFE_SHUTDOWN_ACK) &
+		      V3D_GCA_SAFE_SHUTDOWN_ACK_ACKED) ==
+		     V3D_GCA_SAFE_SHUTDOWN_ACK_ACKED, 100)) {
+		DRM_ERROR("Failed to wait for safe GCA shutdown\n");
+	}
+}
+
+static void
+v3d_reset_v3d(struct v3d_dev *v3d)
+{
+	int version = V3D_BRIDGE_READ(V3D_TOP_GR_BRIDGE_REVISION);
+
+	if (V3D_GET_FIELD(version, V3D_TOP_GR_BRIDGE_MAJOR) == 2) {
+		V3D_BRIDGE_WRITE(V3D_TOP_GR_BRIDGE_SW_INIT_0,
+				 V3D_TOP_GR_BRIDGE_SW_INIT_0_V3D_CLK_108_SW_INIT);
+		V3D_BRIDGE_WRITE(V3D_TOP_GR_BRIDGE_SW_INIT_0, 0);
+
+		/* GFXH-1383: The SW_INIT may cause a stray write to address 0
+		 * of the unit, so reset it to its power-on value here.
+		 */
+		V3D_WRITE(V3D_HUB_AXICFG, V3D_HUB_AXICFG_MAX_LEN_MASK);
+	} else {
+		WARN_ON_ONCE(V3D_GET_FIELD(version,
+					   V3D_TOP_GR_BRIDGE_MAJOR) != 7);
+		V3D_BRIDGE_WRITE(V3D_TOP_GR_BRIDGE_SW_INIT_1,
+				 V3D_TOP_GR_BRIDGE_SW_INIT_1_V3D_CLK_108_SW_INIT);
+		V3D_BRIDGE_WRITE(V3D_TOP_GR_BRIDGE_SW_INIT_1, 0);
+	}
+
+	v3d_init_hw_state(v3d);
+}
+
+void
+v3d_reset(struct v3d_dev *v3d)
+{
+	struct drm_device *dev = &v3d->drm;
+
+	DRM_ERROR("Resetting GPU.\n");
+	trace_v3d_reset_begin(dev);
+
+	/* XXX: only needed for safe powerdown, not reset. */
+	if (false)
+		v3d_idle_axi(v3d, 0);
+
+	v3d_idle_gca(v3d);
+	v3d_reset_v3d(v3d);
+
+	v3d_mmu_set_page_table(v3d);
+	v3d_irq_reset(v3d);
+
+	trace_v3d_reset_end(dev);
+}
+
+static void
+v3d_flush_l3(struct v3d_dev *v3d)
+{
+	if (v3d->ver < 41) {
+		u32 gca_ctrl = V3D_GCA_READ(V3D_GCA_CACHE_CTRL);
+
+		V3D_GCA_WRITE(V3D_GCA_CACHE_CTRL,
+			      gca_ctrl | V3D_GCA_CACHE_CTRL_FLUSH);
+
+		if (v3d->ver < 33) {
+			V3D_GCA_WRITE(V3D_GCA_CACHE_CTRL,
+				      gca_ctrl & ~V3D_GCA_CACHE_CTRL_FLUSH);
+		}
+	}
+}
+
+/* Invalidates the (read-only) L2 cache. */
+static void
+v3d_invalidate_l2(struct v3d_dev *v3d, int core)
+{
+	V3D_CORE_WRITE(core, V3D_CTL_L2CACTL,
+		       V3D_L2CACTL_L2CCLR |
+		       V3D_L2CACTL_L2CENA);
+}
+
+static void
+v3d_invalidate_l1td(struct v3d_dev *v3d, int core)
+{
+	V3D_CORE_WRITE(core, V3D_CTL_L2TCACTL, V3D_L2TCACTL_TMUWCF);
+	if (wait_for(!(V3D_CORE_READ(core, V3D_CTL_L2TCACTL) &
+		       V3D_L2TCACTL_L2TFLS), 100)) {
+		DRM_ERROR("Timeout waiting for L1T write combiner flush\n");
+	}
+}
+
+/* Invalidates texture L2 cachelines */
+static void
+v3d_flush_l2t(struct v3d_dev *v3d, int core)
+{
+	v3d_invalidate_l1td(v3d, core);
+
+	V3D_CORE_WRITE(core, V3D_CTL_L2TCACTL,
+		       V3D_L2TCACTL_L2TFLS |
+		       V3D_SET_FIELD(V3D_L2TCACTL_FLM_FLUSH, V3D_L2TCACTL_FLM));
+	if (wait_for(!(V3D_CORE_READ(core, V3D_CTL_L2TCACTL) &
+		       V3D_L2TCACTL_L2TFLS), 100)) {
+		DRM_ERROR("Timeout waiting for L2T flush\n");
+	}
+}
+
+/* Invalidates the slice caches.  These are read-only caches. */
+static void
+v3d_invalidate_slices(struct v3d_dev *v3d, int core)
+{
+	V3D_CORE_WRITE(core, V3D_CTL_SLCACTL,
+		       V3D_SET_FIELD(0xf, V3D_SLCACTL_TVCCS) |
+		       V3D_SET_FIELD(0xf, V3D_SLCACTL_TDCCS) |
+		       V3D_SET_FIELD(0xf, V3D_SLCACTL_UCC) |
+		       V3D_SET_FIELD(0xf, V3D_SLCACTL_ICC));
+}
+
+/* Invalidates texture L2 cachelines */
+static void
+v3d_invalidate_l2t(struct v3d_dev *v3d, int core)
+{
+	V3D_CORE_WRITE(core,
+		       V3D_CTL_L2TCACTL,
+		       V3D_L2TCACTL_L2TFLS |
+		       V3D_SET_FIELD(V3D_L2TCACTL_FLM_CLEAR, V3D_L2TCACTL_FLM));
+	if (wait_for(!(V3D_CORE_READ(core, V3D_CTL_L2TCACTL) &
+		       V3D_L2TCACTL_L2TFLS), 100)) {
+		DRM_ERROR("Timeout waiting for L2T invalidate\n");
+	}
+}
+
+void
+v3d_invalidate_caches(struct v3d_dev *v3d)
+{
+	v3d_flush_l3(v3d);
+
+	v3d_invalidate_l2(v3d, 0);
+	v3d_invalidate_slices(v3d, 0);
+	v3d_flush_l2t(v3d, 0);
+}
+
+void
+v3d_flush_caches(struct v3d_dev *v3d)
+{
+	v3d_invalidate_l1td(v3d, 0);
+	v3d_invalidate_l2t(v3d, 0);
+}
+
+static void
+v3d_attach_object_fences(struct v3d_exec_info *exec)
+{
+	struct dma_fence *out_fence = &exec->render.base.s_fence->finished;
+	struct v3d_bo *bo;
+	int i;
+
+	for (i = 0; i < exec->bo_count; i++) {
+		bo = to_v3d_bo(&exec->bo[i]->base);
+
+		/* XXX: Use shared fences for read-only objects. */
+		reservation_object_add_excl_fence(bo->resv, out_fence);
+	}
+}
+
+static void
+v3d_unlock_bo_reservations(struct drm_device *dev,
+			   struct v3d_exec_info *exec,
+			   struct ww_acquire_ctx *acquire_ctx)
+{
+	int i;
+
+	for (i = 0; i < exec->bo_count; i++) {
+		struct v3d_bo *bo = to_v3d_bo(&exec->bo[i]->base);
+
+		ww_mutex_unlock(&bo->resv->lock);
+	}
+
+	ww_acquire_fini(acquire_ctx);
+}
+
+/* Takes the reservation lock on all the BOs being referenced, so that
+ * at queue submit time we can update the reservations.
+ *
+ * We don't lock the RCL the tile alloc/state BOs, or overflow memory
+ * (all of which are on exec->unref_list).  They're entirely private
+ * to v3d, so we don't attach dma-buf fences to them.
+ */
+static int
+v3d_lock_bo_reservations(struct drm_device *dev,
+			 struct v3d_exec_info *exec,
+			 struct ww_acquire_ctx *acquire_ctx)
+{
+	int contended_lock = -1;
+	int i, ret;
+	struct v3d_bo *bo;
+
+	ww_acquire_init(acquire_ctx, &reservation_ww_class);
+
+retry:
+	if (contended_lock != -1) {
+		bo = to_v3d_bo(&exec->bo[contended_lock]->base);
+		ret = ww_mutex_lock_slow_interruptible(&bo->resv->lock,
+						       acquire_ctx);
+		if (ret) {
+			ww_acquire_done(acquire_ctx);
+			return ret;
+		}
+	}
+
+	for (i = 0; i < exec->bo_count; i++) {
+		if (i == contended_lock)
+			continue;
+
+		bo = to_v3d_bo(&exec->bo[i]->base);
+
+		ret = ww_mutex_lock_interruptible(&bo->resv->lock, acquire_ctx);
+		if (ret) {
+			int j;
+
+			for (j = 0; j < i; j++) {
+				bo = to_v3d_bo(&exec->bo[j]->base);
+				ww_mutex_unlock(&bo->resv->lock);
+			}
+
+			if (contended_lock != -1 && contended_lock >= i) {
+				bo = to_v3d_bo(&exec->bo[contended_lock]->base);
+
+				ww_mutex_unlock(&bo->resv->lock);
+			}
+
+			if (ret == -EDEADLK) {
+				contended_lock = i;
+				goto retry;
+			}
+
+			ww_acquire_done(acquire_ctx);
+			return ret;
+		}
+	}
+
+	ww_acquire_done(acquire_ctx);
+
+	/* Reserve space for our shared (read-only) fence references,
+	 * before we commit the CL to the hardware.
+	 */
+	for (i = 0; i < exec->bo_count; i++) {
+		bo = to_v3d_bo(&exec->bo[i]->base);
+
+		ret = reservation_object_reserve_shared(bo->resv);
+		if (ret) {
+			v3d_unlock_bo_reservations(dev, exec, acquire_ctx);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * v3d_cl_lookup_bos() - Sets up exec->bo[] with the GEM objects
+ * referenced by the job.
+ * @dev: DRM device
+ * @file_priv: DRM file for this fd
+ * @exec: V3D job being set up
+ *
+ * The command validator needs to reference BOs by their index within
+ * the submitted job's BO list.  This does the validation of the job's
+ * BO list and reference counting for the lifetime of the job.
+ *
+ * Note that this function doesn't need to unreference the BOs on
+ * failure, because that will happen at v3d_exec_cleanup() time.
+ */
+static int
+v3d_cl_lookup_bos(struct drm_device *dev,
+		  struct drm_file *file_priv,
+		  struct drm_v3d_submit_cl *args,
+		  struct v3d_exec_info *exec)
+{
+	u32 *handles;
+	int ret = 0;
+	int i;
+
+	exec->bo_count = args->bo_handle_count;
+
+	if (!exec->bo_count) {
+		/* See comment on bo_index for why we have to check
+		 * this.
+		 */
+		DRM_DEBUG("Rendering requires BOs\n");
+		return -EINVAL;
+	}
+
+	exec->bo = kvmalloc_array(exec->bo_count,
+				  sizeof(struct drm_gem_cma_object *),
+				  GFP_KERNEL | __GFP_ZERO);
+	if (!exec->bo) {
+		DRM_DEBUG("Failed to allocate validated BO pointers\n");
+		return -ENOMEM;
+	}
+
+	handles = kvmalloc_array(exec->bo_count, sizeof(u32), GFP_KERNEL);
+	if (!handles) {
+		ret = -ENOMEM;
+		DRM_DEBUG("Failed to allocate incoming GEM handles\n");
+		goto fail;
+	}
+
+	if (copy_from_user(handles,
+			   (void __user *)(uintptr_t)args->bo_handles,
+			   exec->bo_count * sizeof(u32))) {
+		ret = -EFAULT;
+		DRM_DEBUG("Failed to copy in GEM handles\n");
+		goto fail;
+	}
+
+	spin_lock(&file_priv->table_lock);
+	for (i = 0; i < exec->bo_count; i++) {
+		struct drm_gem_object *bo = idr_find(&file_priv->object_idr,
+						     handles[i]);
+		if (!bo) {
+			DRM_DEBUG("Failed to look up GEM BO %d: %d\n",
+				  i, handles[i]);
+			ret = -ENOENT;
+			spin_unlock(&file_priv->table_lock);
+			goto fail;
+		}
+		drm_gem_object_get(bo);
+		exec->bo[i] = to_v3d_bo(bo);
+	}
+	spin_unlock(&file_priv->table_lock);
+
+fail:
+	kvfree(handles);
+	return ret;
+}
+
+static void
+v3d_exec_cleanup(struct kref *ref)
+{
+	struct v3d_exec_info *exec = container_of(ref, struct v3d_exec_info,
+						  refcount);
+	struct v3d_dev *v3d = exec->v3d;
+	unsigned int i;
+	struct v3d_bo *bo, *save;
+
+	dma_fence_put(exec->bin.in_fence);
+	dma_fence_put(exec->render.in_fence);
+
+	dma_fence_put(exec->bin.done_fence);
+	dma_fence_put(exec->render.done_fence);
+
+	dma_fence_put(exec->bin_done_fence);
+
+	for (i = 0; i < exec->bo_count; i++)
+		drm_gem_object_put_unlocked(&exec->bo[i]->base);
+	kvfree(exec->bo);
+
+	list_for_each_entry_safe(bo, save, &exec->unref_list, unref_head) {
+		drm_gem_object_put_unlocked(&bo->base);
+	}
+
+	pm_runtime_mark_last_busy(v3d->dev);
+	pm_runtime_put_autosuspend(v3d->dev);
+
+	kfree(exec);
+}
+
+void v3d_exec_put(struct v3d_exec_info *exec)
+{
+	kref_put(&exec->refcount, v3d_exec_cleanup);
+}
+
+int
+v3d_wait_bo_ioctl(struct drm_device *dev, void *data,
+		  struct drm_file *file_priv)
+{
+	int ret;
+	struct drm_v3d_wait_bo *args = data;
+	struct drm_gem_object *gem_obj;
+	struct v3d_bo *bo;
+	ktime_t start = ktime_get();
+	u64 delta_ns;
+	unsigned long timeout_jiffies =
+		nsecs_to_jiffies_timeout(args->timeout_ns);
+
+	if (args->pad != 0)
+		return -EINVAL;
+
+	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
+	if (!gem_obj) {
+		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
+		return -EINVAL;
+	}
+	bo = to_v3d_bo(gem_obj);
+
+	ret = reservation_object_wait_timeout_rcu(bo->resv,
+						  true, true,
+						  timeout_jiffies);
+
+	if (ret == 0)
+		ret = -ETIME;
+	else if (ret > 0)
+		ret = 0;
+
+	/* Decrement the user's timeout, in case we got interrupted
+	 * such that the ioctl will be restarted.
+	 */
+	delta_ns = ktime_to_ns(ktime_sub(ktime_get(), start));
+	if (delta_ns < args->timeout_ns)
+		args->timeout_ns -= delta_ns;
+	else
+		args->timeout_ns = 0;
+
+	/* Asked to wait beyond the jiffie/scheduler precision? */
+	if (ret == -ETIME && args->timeout_ns)
+		ret = -EAGAIN;
+
+	drm_gem_object_put_unlocked(gem_obj);
+
+	return ret;
+}
+
+/**
+ * v3d_submit_cl_ioctl() - Submits a job (frame) to the V3D.
+ * @dev: DRM device
+ * @data: ioctl argument
+ * @file_priv: DRM file for this fd
+ *
+ * This is the main entrypoint for userspace to submit a 3D frame to
+ * the GPU.  Userspace provides the binner command list (if
+ * applicable), and the kernel sets up the render command list to draw
+ * to the framebuffer described in the ioctl, using the command lists
+ * that the 3D engine's binner will produce.
+ */
+int
+v3d_submit_cl_ioctl(struct drm_device *dev, void *data,
+		    struct drm_file *file_priv)
+{
+	struct v3d_dev *v3d = to_v3d_dev(dev);
+	struct v3d_file_priv *v3d_priv = file_priv->driver_priv;
+	struct drm_v3d_submit_cl *args = data;
+	struct v3d_exec_info *exec;
+	struct ww_acquire_ctx acquire_ctx;
+	struct drm_syncobj *sync_out;
+	int ret = 0;
+
+	if (args->pad != 0) {
+		DRM_INFO("pad must be zero: %d\n", args->pad);
+		return -EINVAL;
+	}
+
+	exec = kcalloc(1, sizeof(*exec), GFP_KERNEL);
+	if (!exec)
+		return -ENOMEM;
+
+	ret = pm_runtime_get_sync(v3d->dev);
+	if (ret < 0) {
+		kfree(exec);
+		return ret;
+	}
+
+	kref_init(&exec->refcount);
+
+	ret = drm_syncobj_find_fence(file_priv, args->in_sync_bcl,
+				     &exec->bin.in_fence);
+	if (ret == -EINVAL)
+		goto fail;
+
+	ret = drm_syncobj_find_fence(file_priv, args->in_sync_rcl,
+				     &exec->render.in_fence);
+	if (ret == -EINVAL)
+		goto fail;
+
+	exec->qma = args->qma;
+	exec->qms = args->qms;
+	exec->qts = args->qts;
+	exec->bin.exec = exec;
+	exec->bin.start = args->bcl_start;
+	exec->bin.end = args->bcl_end;
+	exec->render.exec = exec;
+	exec->render.start = args->rcl_start;
+	exec->render.end = args->rcl_end;
+	exec->v3d = v3d;
+	INIT_LIST_HEAD(&exec->unref_list);
+
+	ret = v3d_cl_lookup_bos(dev, file_priv, args, exec);
+	if (ret)
+		goto fail;
+
+	ret = v3d_lock_bo_reservations(dev, exec, &acquire_ctx);
+	if (ret)
+		goto fail;
+
+	if (exec->bin.start != exec->bin.end) {
+		ret = drm_sched_job_init(&exec->bin.base,
+					 &v3d->queue[V3D_BIN].sched,
+					 &v3d_priv->sched_entity[V3D_BIN],
+					 v3d_priv);
+		if (ret)
+			goto fail_unreserve;
+
+		exec->bin_done_fence =
+			dma_fence_get(&exec->bin.base.s_fence->finished);
+
+		kref_get(&exec->refcount); /* put by scheduler job completion */
+		drm_sched_entity_push_job(&exec->bin.base,
+					  &v3d_priv->sched_entity[V3D_BIN]);
+	}
+
+	ret = drm_sched_job_init(&exec->render.base,
+				 &v3d->queue[V3D_RENDER].sched,
+				 &v3d_priv->sched_entity[V3D_RENDER],
+				 v3d_priv);
+	if (ret)
+		goto fail_unreserve;
+
+	kref_get(&exec->refcount); /* put by scheduler job completion */
+	drm_sched_entity_push_job(&exec->render.base,
+				  &v3d_priv->sched_entity[V3D_RENDER]);
+
+	v3d_attach_object_fences(exec);
+
+	v3d_unlock_bo_reservations(dev, exec, &acquire_ctx);
+
+	/* Update the return sync object for the */
+	sync_out = drm_syncobj_find(file_priv, args->out_sync);
+	if (sync_out) {
+		drm_syncobj_replace_fence(sync_out,
+					  &exec->render.base.s_fence->finished);
+		drm_syncobj_put(sync_out);
+	}
+
+	v3d_exec_put(exec);
+
+	return 0;
+
+fail_unreserve:
+	v3d_unlock_bo_reservations(dev, exec, &acquire_ctx);
+fail:
+	v3d_exec_put(exec);
+
+	return ret;
+}
+
+int
+v3d_gem_init(struct drm_device *dev)
+{
+	struct v3d_dev *v3d = to_v3d_dev(dev);
+	u32 pt_size = 4096 * 1024;
+	int ret, i;
+
+	for (i = 0; i < V3D_MAX_QUEUES; i++)
+		v3d->queue[i].fence_context = dma_fence_context_alloc(1);
+
+	spin_lock_init(&v3d->mm_lock);
+	spin_lock_init(&v3d->job_lock);
+	mutex_init(&v3d->bo_lock);
+	mutex_init(&v3d->reset_lock);
+
+	/* Note: We don't allocate address 0.  Various bits of HW
+	 * treat 0 as special, such as the occlusion query counters
+	 * where 0 means "disabled".
+	 */
+	drm_mm_init(&v3d->mm, 1, pt_size / sizeof(u32) - 1);
+
+	v3d->pt = dma_alloc_wc(v3d->dev, pt_size,
+			       &v3d->pt_paddr,
+			       GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO);
+	if (!v3d->pt) {
+		drm_mm_takedown(&v3d->mm);
+		dev_err(v3d->dev,
+			"Failed to allocate page tables. "
+			"Please ensure you have CMA enabled.\n");
+		return -ENOMEM;
+	}
+
+	v3d_init_hw_state(v3d);
+	v3d_mmu_set_page_table(v3d);
+
+	ret = v3d_sched_init(v3d);
+	if (ret) {
+		drm_mm_takedown(&v3d->mm);
+		dma_free_coherent(v3d->dev, 4096 * 1024, (void *)v3d->pt,
+				  v3d->pt_paddr);
+	}
+
+	return 0;
+}
+
+void
+v3d_gem_destroy(struct drm_device *dev)
+{
+	struct v3d_dev *v3d = to_v3d_dev(dev);
+	enum v3d_queue q;
+
+	v3d_sched_fini(v3d);
+
+	/* Waiting for exec to finish would need to be done before
+	 * unregistering V3D.
+	 */
+	for (q = 0; q < V3D_MAX_QUEUES; q++) {
+		WARN_ON(v3d->queue[q].emit_seqno !=
+			v3d->queue[q].finished_seqno);
+	}
+
+	drm_mm_takedown(&v3d->mm);
+
+	dma_free_coherent(v3d->dev, 4096 * 1024, (void *)v3d->pt, v3d->pt_paddr);
+}