1 files changed, 435 insertions, 0 deletions
diff --git a/drivers/misc/habanalabs/common/context.c b/drivers/misc/habanalabs/common/context.c
new file mode 100644
index 000000000..2f4620b79
--- /dev/null
+++ b/drivers/misc/habanalabs/common/context.c
@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2016-2021 HabanaLabs, Ltd.
+ * All Rights Reserved.
+ */
+
+#include "habanalabs.h"
+
+#include <linux/slab.h>
+
+void hl_encaps_handle_do_release(struct kref *ref)
+{
+	struct hl_cs_encaps_sig_handle *handle =
+		container_of(ref, struct hl_cs_encaps_sig_handle, refcount);
+	struct hl_encaps_signals_mgr *mgr = &handle->ctx->sig_mgr;
+
+	spin_lock(&mgr->lock);
+	idr_remove(&mgr->handles, handle->id);
+	spin_unlock(&mgr->lock);
+
+	hl_ctx_put(handle->ctx);
+	kfree(handle);
+}
+
+static void hl_encaps_handle_do_release_sob(struct kref *ref)
+{
+	struct hl_cs_encaps_sig_handle *handle =
+		container_of(ref, struct hl_cs_encaps_sig_handle, refcount);
+	struct hl_encaps_signals_mgr *mgr = &handle->ctx->sig_mgr;
+
+	/* if we're here, then there was a signals reservation but cs with
+	 * encaps signals wasn't submitted, so need to put refcount
+	 * to hw_sob taken at the reservation.
+	 */
+	hw_sob_put(handle->hw_sob);
+
+	spin_lock(&mgr->lock);
+	idr_remove(&mgr->handles, handle->id);
+	spin_unlock(&mgr->lock);
+
+	hl_ctx_put(handle->ctx);
+	kfree(handle);
+}
+
+static void hl_encaps_sig_mgr_init(struct hl_encaps_signals_mgr *mgr)
+{
+	spin_lock_init(&mgr->lock);
+	idr_init(&mgr->handles);
+}
+
+static void hl_encaps_sig_mgr_fini(struct hl_device *hdev,
+			struct hl_encaps_signals_mgr *mgr)
+{
+	struct hl_cs_encaps_sig_handle *handle;
+	struct idr *idp;
+	u32 id;
+
+	idp = &mgr->handles;
+
+	if (!idr_is_empty(idp)) {
+		dev_warn(hdev->dev, "device released while some encaps signals handles are still allocated\n");
+		idr_for_each_entry(idp, handle, id)
+			kref_put(&handle->refcount,
+					hl_encaps_handle_do_release_sob);
+	}
+
+	idr_destroy(&mgr->handles);
+}
+
+static void hl_ctx_fini(struct hl_ctx *ctx)
+{
+	struct hl_device *hdev = ctx->hdev;
+	int i;
+
+	/* Release all allocated HW block mapped list entries and destroy
+	 * the mutex.
+	 */
+	hl_hw_block_mem_fini(ctx);
+
+	/*
+	 * If we arrived here, there are no jobs waiting for this context
+	 * on its queues so we can safely remove it.
+	 * This is because for each CS, we increment the ref count and for
+	 * every CS that was finished we decrement it and we won't arrive
+	 * to this function unless the ref count is 0
+	 */
+
+	for (i = 0 ; i < hdev->asic_prop.max_pending_cs ; i++)
+		hl_fence_put(ctx->cs_pending[i]);
+
+	kfree(ctx->cs_pending);
+
+	if (ctx->asid != HL_KERNEL_ASID_ID) {
+		dev_dbg(hdev->dev, "closing user context %d\n", ctx->asid);
+
+		/* The engines are stopped as there is no executing CS, but the
+		 * Coresight might be still working by accessing addresses
+		 * related to the stopped engines. Hence stop it explicitly.
+		 */
+		if (hdev->in_debug)
+			hl_device_set_debug_mode(hdev, ctx, false);
+
+		hdev->asic_funcs->ctx_fini(ctx);
+
+		hl_dec_ctx_fini(ctx);
+
+		hl_cb_va_pool_fini(ctx);
+		hl_vm_ctx_fini(ctx);
+		hl_asid_free(hdev, ctx->asid);
+		hl_encaps_sig_mgr_fini(hdev, &ctx->sig_mgr);
+	} else {
+		dev_dbg(hdev->dev, "closing kernel context\n");
+		hdev->asic_funcs->ctx_fini(ctx);
+		hl_vm_ctx_fini(ctx);
+		hl_mmu_ctx_fini(ctx);
+	}
+}
+
+void hl_ctx_do_release(struct kref *ref)
+{
+	struct hl_ctx *ctx;
+
+	ctx = container_of(ref, struct hl_ctx, refcount);
+
+	hl_ctx_fini(ctx);
+
+	if (ctx->hpriv) {
+		struct hl_fpriv *hpriv = ctx->hpriv;
+
+		mutex_lock(&hpriv->ctx_lock);
+		hpriv->ctx = NULL;
+		mutex_unlock(&hpriv->ctx_lock);
+
+		hl_hpriv_put(hpriv);
+	}
+
+	kfree(ctx);
+}
+
+int hl_ctx_create(struct hl_device *hdev, struct hl_fpriv *hpriv)
+{
+	struct hl_ctx_mgr *ctx_mgr = &hpriv->ctx_mgr;
+	struct hl_ctx *ctx;
+	int rc;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx) {
+		rc = -ENOMEM;
+		goto out_err;
+	}
+
+	mutex_lock(&ctx_mgr->lock);
+	rc = idr_alloc(&ctx_mgr->handles, ctx, 1, 0, GFP_KERNEL);
+	mutex_unlock(&ctx_mgr->lock);
+
+	if (rc < 0) {
+		dev_err(hdev->dev, "Failed to allocate IDR for a new CTX\n");
+		goto free_ctx;
+	}
+
+	ctx->handle = rc;
+
+	rc = hl_ctx_init(hdev, ctx, false);
+	if (rc)
+		goto remove_from_idr;
+
+	hl_hpriv_get(hpriv);
+	ctx->hpriv = hpriv;
+
+	/* TODO: remove for multiple contexts per process */
+	hpriv->ctx = ctx;
+
+	/* TODO: remove the following line for multiple process support */
+	hdev->is_compute_ctx_active = true;
+
+	return 0;
+
+remove_from_idr:
+	mutex_lock(&ctx_mgr->lock);
+	idr_remove(&ctx_mgr->handles, ctx->handle);
+	mutex_unlock(&ctx_mgr->lock);
+free_ctx:
+	kfree(ctx);
+out_err:
+	return rc;
+}
+
+int hl_ctx_init(struct hl_device *hdev, struct hl_ctx *ctx, bool is_kernel_ctx)
+{
+	int rc = 0, i;
+
+	ctx->hdev = hdev;
+
+	kref_init(&ctx->refcount);
+
+	ctx->cs_sequence = 1;
+	spin_lock_init(&ctx->cs_lock);
+	atomic_set(&ctx->thread_ctx_switch_token, 1);
+	ctx->thread_ctx_switch_wait_token = 0;
+	ctx->cs_pending = kcalloc(hdev->asic_prop.max_pending_cs,
+				sizeof(struct hl_fence *),
+				GFP_KERNEL);
+	if (!ctx->cs_pending)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&ctx->outcome_store.used_list);
+	INIT_LIST_HEAD(&ctx->outcome_store.free_list);
+	hash_init(ctx->outcome_store.outcome_map);
+	for (i = 0; i < ARRAY_SIZE(ctx->outcome_store.nodes_pool); ++i)
+		list_add(&ctx->outcome_store.nodes_pool[i].list_link,
+			 &ctx->outcome_store.free_list);
+
+	hl_hw_block_mem_init(ctx);
+
+	if (is_kernel_ctx) {
+		ctx->asid = HL_KERNEL_ASID_ID; /* Kernel driver gets ASID 0 */
+		rc = hl_vm_ctx_init(ctx);
+		if (rc) {
+			dev_err(hdev->dev, "Failed to init mem ctx module\n");
+			rc = -ENOMEM;
+			goto err_hw_block_mem_fini;
+		}
+
+		rc = hdev->asic_funcs->ctx_init(ctx);
+		if (rc) {
+			dev_err(hdev->dev, "ctx_init failed\n");
+			goto err_vm_ctx_fini;
+		}
+	} else {
+		ctx->asid = hl_asid_alloc(hdev);
+		if (!ctx->asid) {
+			dev_err(hdev->dev, "No free ASID, failed to create context\n");
+			rc = -ENOMEM;
+			goto err_hw_block_mem_fini;
+		}
+
+		rc = hl_vm_ctx_init(ctx);
+		if (rc) {
+			dev_err(hdev->dev, "Failed to init mem ctx module\n");
+			rc = -ENOMEM;
+			goto err_asid_free;
+		}
+
+		rc = hl_cb_va_pool_init(ctx);
+		if (rc) {
+			dev_err(hdev->dev,
+				"Failed to init VA pool for mapped CB\n");
+			goto err_vm_ctx_fini;
+		}
+
+		rc = hdev->asic_funcs->ctx_init(ctx);
+		if (rc) {
+			dev_err(hdev->dev, "ctx_init failed\n");
+			goto err_cb_va_pool_fini;
+		}
+
+		hl_encaps_sig_mgr_init(&ctx->sig_mgr);
+
+		dev_dbg(hdev->dev, "create user context %d\n", ctx->asid);
+	}
+
+	return 0;
+
+err_cb_va_pool_fini:
+	hl_cb_va_pool_fini(ctx);
+err_vm_ctx_fini:
+	hl_vm_ctx_fini(ctx);
+err_asid_free:
+	if (ctx->asid != HL_KERNEL_ASID_ID)
+		hl_asid_free(hdev, ctx->asid);
+err_hw_block_mem_fini:
+	hl_hw_block_mem_fini(ctx);
+	kfree(ctx->cs_pending);
+
+	return rc;
+}
+
+static int hl_ctx_get_unless_zero(struct hl_ctx *ctx)
+{
+	return kref_get_unless_zero(&ctx->refcount);
+}
+
+void hl_ctx_get(struct hl_ctx *ctx)
+{
+	kref_get(&ctx->refcount);
+}
+
+int hl_ctx_put(struct hl_ctx *ctx)
+{
+	return kref_put(&ctx->refcount, hl_ctx_do_release);
+}
+
+struct hl_ctx *hl_get_compute_ctx(struct hl_device *hdev)
+{
+	struct hl_ctx *ctx = NULL;
+	struct hl_fpriv *hpriv;
+
+	mutex_lock(&hdev->fpriv_list_lock);
+
+	list_for_each_entry(hpriv, &hdev->fpriv_list, dev_node) {
+		mutex_lock(&hpriv->ctx_lock);
+		ctx = hpriv->ctx;
+		if (ctx && !hl_ctx_get_unless_zero(ctx))
+			ctx = NULL;
+		mutex_unlock(&hpriv->ctx_lock);
+
+		/* There can only be a single user which has opened the compute device, so exit
+		 * immediately once we find its context or if we see that it has been released
+		 */
+		break;
+	}
+
+	mutex_unlock(&hdev->fpriv_list_lock);
+
+	return ctx;
+}
+
+/*
+ * hl_ctx_get_fence_locked - get CS fence under CS lock
+ *
+ * @ctx: pointer to the context structure.
+ * @seq: CS sequences number
+ *
+ * @return valid fence pointer on success, NULL if fence is gone, otherwise
+ *         error pointer.
+ *
+ * NOTE: this function shall be called with cs_lock locked
+ */
+static struct hl_fence *hl_ctx_get_fence_locked(struct hl_ctx *ctx, u64 seq)
+{
+	struct asic_fixed_properties *asic_prop = &ctx->hdev->asic_prop;
+	struct hl_fence *fence;
+
+	if (seq >= ctx->cs_sequence)
+		return ERR_PTR(-EINVAL);
+
+	if (seq + asic_prop->max_pending_cs < ctx->cs_sequence)
+		return NULL;
+
+	fence = ctx->cs_pending[seq & (asic_prop->max_pending_cs - 1)];
+	hl_fence_get(fence);
+	return fence;
+}
+
+struct hl_fence *hl_ctx_get_fence(struct hl_ctx *ctx, u64 seq)
+{
+	struct hl_fence *fence;
+
+	spin_lock(&ctx->cs_lock);
+
+	fence = hl_ctx_get_fence_locked(ctx, seq);
+
+	spin_unlock(&ctx->cs_lock);
+
+	return fence;
+}
+
+/*
+ * hl_ctx_get_fences - get multiple CS fences under the same CS lock
+ *
+ * @ctx: pointer to the context structure.
+ * @seq_arr: array of CS sequences to wait for
+ * @fence: fence array to store the CS fences
+ * @arr_len: length of seq_arr and fence_arr
+ *
+ * @return 0 on success, otherwise non 0 error code
+ */
+int hl_ctx_get_fences(struct hl_ctx *ctx, u64 *seq_arr,
+				struct hl_fence **fence, u32 arr_len)
+{
+	struct hl_fence **fence_arr_base = fence;
+	int i, rc = 0;
+
+	spin_lock(&ctx->cs_lock);
+
+	for (i = 0; i < arr_len; i++, fence++) {
+		u64 seq = seq_arr[i];
+
+		*fence = hl_ctx_get_fence_locked(ctx, seq);
+
+		if (IS_ERR(*fence)) {
+			dev_err(ctx->hdev->dev,
+				"Failed to get fence for CS with seq 0x%llx\n",
+					seq);
+			rc = PTR_ERR(*fence);
+			break;
+		}
+	}
+
+	spin_unlock(&ctx->cs_lock);
+
+	if (rc)
+		hl_fences_put(fence_arr_base, i);
+
+	return rc;
+}
+
+/*
+ * hl_ctx_mgr_init - initialize the context manager
+ *
+ * @ctx_mgr: pointer to context manager structure
+ *
+ * This manager is an object inside the hpriv object of the user process.
+ * The function is called when a user process opens the FD.
+ */
+void hl_ctx_mgr_init(struct hl_ctx_mgr *ctx_mgr)
+{
+	mutex_init(&ctx_mgr->lock);
+	idr_init(&ctx_mgr->handles);
+}
+
+/*
+ * hl_ctx_mgr_fini - finalize the context manager
+ *
+ * @hdev: pointer to device structure
+ * @ctx_mgr: pointer to context manager structure
+ *
+ * This function goes over all the contexts in the manager and frees them.
+ * It is called when a process closes the FD.
+ */
+void hl_ctx_mgr_fini(struct hl_device *hdev, struct hl_ctx_mgr *ctx_mgr)
+{
+	struct hl_ctx *ctx;
+	struct idr *idp;
+	u32 id;
+
+	idp = &ctx_mgr->handles;
+
+	idr_for_each_entry(idp, ctx, id)
+		kref_put(&ctx->refcount, hl_ctx_do_release);
+
+	idr_destroy(&ctx_mgr->handles);
+	mutex_destroy(&ctx_mgr->lock);
+}