2 files changed, 83 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/core/memory.h b/drivers/gpu/drm/nouveau/include/nvkm/core/memory.h
index 14ce7df9864e..ce04e0f74f0c 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/core/memory.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/core/memory.h
@@ -5,6 +5,11 @@ struct nvkm_device;
 struct nvkm_vma;
 struct nvkm_vm;
 
+struct nvkm_tags {
+	struct nvkm_mm_node *mn;
+	refcount_t refcount;
+};
+
 enum nvkm_memory_target {
 	NVKM_MEM_TARGET_INST, /* instance memory */
 	NVKM_MEM_TARGET_VRAM, /* video memory */
@@ -15,6 +20,7 @@ enum nvkm_memory_target {
 struct nvkm_memory {
 	const struct nvkm_memory_func *func;
 	const struct nvkm_memory_ptrs *ptrs;
+	struct nvkm_tags *tags;
 };
 
 struct nvkm_memory_func {
@@ -37,6 +43,12 @@ void nvkm_memory_ctor(const struct nvkm_memory_func *, struct nvkm_memory *);
 int nvkm_memory_new(struct nvkm_device *, enum nvkm_memory_target,
 		    u64 size, u32 align, bool zero, struct nvkm_memory **);
 void nvkm_memory_del(struct nvkm_memory **);
+int nvkm_memory_tags_get(struct nvkm_memory *, struct nvkm_device *, u32 tags,
+			 void (*clear)(struct nvkm_device *, u32, u32),
+			 struct nvkm_tags **);
+void nvkm_memory_tags_put(struct nvkm_memory *, struct nvkm_device *,
+			  struct nvkm_tags **);
+
 #define nvkm_memory_target(p) (p)->func->target(p)
 #define nvkm_memory_addr(p) (p)->func->addr(p)
 #define nvkm_memory_size(p) (p)->func->size(p)
diff --git a/drivers/gpu/drm/nouveau/nvkm/core/memory.c b/drivers/gpu/drm/nouveau/nvkm/core/memory.c
index 8903c04c977e..13cfcdde99fd 100644
--- a/drivers/gpu/drm/nouveau/nvkm/core/memory.c
+++ b/drivers/gpu/drm/nouveau/nvkm/core/memory.c
@@ -22,9 +22,80 @@
  * Authors: Ben Skeggs <bskeggs@redhat.com>
  */
 #include <core/memory.h>
+#include <core/mm.h>
+#include <subdev/fb.h>
 #include <subdev/instmem.h>
 
 void
+nvkm_memory_tags_put(struct nvkm_memory *memory, struct nvkm_device *device,
+		     struct nvkm_tags **ptags)
+{
+	struct nvkm_fb *fb = device->fb;
+	struct nvkm_tags *tags = *ptags;
+	if (tags) {
+		mutex_lock(&fb->subdev.mutex);
+		if (refcount_dec_and_test(&tags->refcount)) {
+			nvkm_mm_free(&fb->tags, &tags->mn);
+			kfree(memory->tags);
+			memory->tags = NULL;
+		}
+		mutex_unlock(&fb->subdev.mutex);
+		*ptags = NULL;
+	}
+}
+
+int
+nvkm_memory_tags_get(struct nvkm_memory *memory, struct nvkm_device *device,
+		     u32 nr, void (*clr)(struct nvkm_device *, u32, u32),
+		     struct nvkm_tags **ptags)
+{
+	struct nvkm_fb *fb = device->fb;
+	struct nvkm_tags *tags;
+
+	mutex_lock(&fb->subdev.mutex);
+	if ((tags = memory->tags)) {
+		/* If comptags exist for the memory, but a different amount
+		 * than requested, the buffer is being mapped with settings
+		 * that are incompatible with existing mappings.
+		 */
+		if (tags->mn && tags->mn->length != nr) {
+			mutex_unlock(&fb->subdev.mutex);
+			return -EINVAL;
+		}
+
+		refcount_inc(&tags->refcount);
+		*ptags = tags;
+		return 0;
+	}
+
+	if (!(tags = kmalloc(sizeof(*tags), GFP_KERNEL))) {
+		mutex_unlock(&fb->subdev.mutex);
+		return -ENOMEM;
+	}
+
+	if (!nvkm_mm_head(&fb->tags, 0, 1, nr, nr, 1, &tags->mn)) {
+		if (clr)
+			clr(device, tags->mn->offset, tags->mn->length);
+	} else {
+		/* Failure to allocate HW comptags is not an error, the
+		 * caller should fall back to an uncompressed map.
+		 *
+		 * As memory can be mapped in multiple places, we still
+		 * need to track the allocation failure and ensure that
+		 * any additional mappings remain uncompressed.
+		 *
+		 * This is handled by returning an empty nvkm_tags.
+		 */
+		tags->mn = NULL;
+	}
+
+	refcount_set(&tags->refcount, 1);
+	mutex_unlock(&fb->subdev.mutex);
+	*ptags = tags;
+	return 0;
+}
+
+void
 nvkm_memory_ctor(const struct nvkm_memory_func *func,
 		 struct nvkm_memory *memory)
 {