1 files changed, 58 insertions, 0 deletions
diff --git a/drivers/misc/habanalabs/common/asid.c b/drivers/misc/habanalabs/common/asid.c
new file mode 100644
index 000000000..c9c2619cc
--- /dev/null
+++ b/drivers/misc/habanalabs/common/asid.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2016-2019 HabanaLabs, Ltd.
+ * All Rights Reserved.
+ */
+
+#include "habanalabs.h"
+
+#include <linux/slab.h>
+
+int hl_asid_init(struct hl_device *hdev)
+{
+	hdev->asid_bitmap = bitmap_zalloc(hdev->asic_prop.max_asid, GFP_KERNEL);
+	if (!hdev->asid_bitmap)
+		return -ENOMEM;
+
+	mutex_init(&hdev->asid_mutex);
+
+	/* ASID 0 is reserved for the kernel driver and device CPU */
+	set_bit(0, hdev->asid_bitmap);
+
+	return 0;
+}
+
+void hl_asid_fini(struct hl_device *hdev)
+{
+	mutex_destroy(&hdev->asid_mutex);
+	bitmap_free(hdev->asid_bitmap);
+}
+
+unsigned long hl_asid_alloc(struct hl_device *hdev)
+{
+	unsigned long found;
+
+	mutex_lock(&hdev->asid_mutex);
+
+	found = find_first_zero_bit(hdev->asid_bitmap,
+					hdev->asic_prop.max_asid);
+	if (found == hdev->asic_prop.max_asid)
+		found = 0;
+	else
+		set_bit(found, hdev->asid_bitmap);
+
+	mutex_unlock(&hdev->asid_mutex);
+
+	return found;
+}
+
+void hl_asid_free(struct hl_device *hdev, unsigned long asid)
+{
+	if (asid == HL_KERNEL_ASID_ID || asid >= hdev->asic_prop.max_asid) {
+		dev_crit(hdev->dev, "Invalid ASID %lu", asid);
+		return;
+	}
+
+	clear_bit(asid, hdev->asid_bitmap);
+}