drm/nouveau/nvkm: add a replacement for nvkm_notify

This replaces the twisty, confusing, relationship between nvkm_event and
nvkm_notify with something much simpler, and less racey.  It also places
events in the object tree hierarchy, which will allow a heap of the code
tracking events across allocation/teardown/suspend to be removed.

This commit just adds the new interfaces, and passes the owning subdev to
the event constructor to enable debug-tracing in the new code.

v2:
- use ?: (lyude)

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

6 files changed, 101 insertions, 1 deletions

diff --git a/drivers/gpu/drm/nouveau/include/nvif/class.h b/drivers/gpu/drm/nouveau/include/nvif/class.h
index 03f0f7c299f2..29448f77069b 100644
--- a/drivers/gpu/drm/nouveau/include/nvif/class.h
+++ b/drivers/gpu/drm/nouveau/include/nvif/class.h
@@ -32,6 +32,8 @@
 #define NVIF_CLASS_VMM_GM200                         /* ifb00d.h */  0x8000b00d
 #define NVIF_CLASS_VMM_GP100                         /* ifc00d.h */  0x8000c00d
 
+#define NVIF_CLASS_EVENT                             /* if000e.h */  0x8000000e
+
 #define NVIF_CLASS_DISP                              /* if0010.h */  0x80000010
 #define NVIF_CLASS_CONN                              /* if0011.h */  0x80000011
 #define NVIF_CLASS_OUTP                              /* if0012.h */  0x80000012
diff --git a/drivers/gpu/drm/nouveau/include/nvif/event.h b/drivers/gpu/drm/nouveau/include/nvif/event.h
index a6b1ee4f10ca..a510ba4ad487 100644
--- a/drivers/gpu/drm/nouveau/include/nvif/event.h
+++ b/drivers/gpu/drm/nouveau/include/nvif/event.h
@@ -1,6 +1,38 @@
 /* SPDX-License-Identifier: MIT */
 #ifndef __NVIF_EVENT_H__
 #define __NVIF_EVENT_H__
+#include <nvif/object.h>
+#include <nvif/if000e.h>
+struct nvif_event;
+
+#define NVIF_EVENT_KEEP 0
+#define NVIF_EVENT_DROP 1
+typedef int (*nvif_event_func)(struct nvif_event *, void *repv, u32 repc);
+
+struct nvif_event {
+	struct nvif_object object;
+	nvif_event_func func;
+};
+
+static inline bool
+nvif_event_constructed(struct nvif_event *event)
+{
+	return nvif_object_constructed(&event->object);
+}
+
+int nvif_event_ctor_(struct nvif_object *, const char *, u32, nvif_event_func, bool,
+		     struct nvif_event_v0 *, u32, bool, struct nvif_event *);
+
+static inline int
+nvif_event_ctor(struct nvif_object *parent, const char *name, u32 handle, nvif_event_func func,
+		bool wait, struct nvif_event_v0 *args, u32 argc, struct nvif_event *event)
+{
+	return nvif_event_ctor_(parent, name, handle, func, wait, args, argc, true, event);
+}
+
+void nvif_event_dtor(struct nvif_event *);
+int nvif_event_allow(struct nvif_event *);
+int nvif_event_block(struct nvif_event *);
 
 struct nvif_notify_req_v0 {
 	__u8  version;
diff --git a/drivers/gpu/drm/nouveau/include/nvif/if000e.h b/drivers/gpu/drm/nouveau/include/nvif/if000e.h
new file mode 100644
index 000000000000..90a936cb1766
--- /dev/null
+++ b/drivers/gpu/drm/nouveau/include/nvif/if000e.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: MIT */
+#ifndef __NVIF_IF000E_H__
+#define __NVIF_IF000E_H__
+
+union nvif_event_args {
+	struct nvif_event_v0 {
+		__u8 version;
+		__u8 wait;
+		__u8 pad02[6];
+		__u8 data[];
+	} v0;
+};
+
+#define NVIF_EVENT_V0_ALLOW 0x00
+#define NVIF_EVENT_V0_BLOCK 0x01
+
+union nvif_event_allow_args {
+	struct nvif_event_allow_vn {
+	} vn;
+};
+
+union nvif_event_block_args {
+	struct nvif_event_block_vn {
+	} vn;
+};
+#endif
diff --git a/drivers/gpu/drm/nouveau/include/nvkm/core/client.h b/drivers/gpu/drm/nouveau/include/nvkm/core/client.h
index 2f86606e708c..2eb22aaed700 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/core/client.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/core/client.h
@@ -15,6 +15,7 @@ struct nvkm_client {
 
 	void *data;
 	int (*ntfy)(const void *, u32, const void *, u32);
+	int (*event)(u64 token, void *argv, u32 argc);
 
 	struct list_head umem;
 	spinlock_t lock;
@@ -23,6 +24,7 @@ struct nvkm_client {
 int  nvkm_client_new(const char *name, u64 device, const char *cfg,
 		     const char *dbg,
 		     int (*)(const void *, u32, const void *, u32),
+		     int (*)(u64, void *, u32),
 		     struct nvkm_client **);
 struct nvkm_client *nvkm_client_search(struct nvkm_client *, u64 handle);
 
diff --git a/drivers/gpu/drm/nouveau/include/nvkm/core/event.h b/drivers/gpu/drm/nouveau/include/nvkm/core/event.h
index a7a413f07a78..d6755a89f587 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/core/event.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/core/event.h
@@ -4,9 +4,12 @@
 #include <core/os.h>
 struct nvkm_notify;
 struct nvkm_object;
+struct nvkm_oclass;
+struct nvkm_uevent;
 
 struct nvkm_event {
 	const struct nvkm_event_func *func;
+	struct nvkm_subdev *subdev;
 
 	int types_nr;
 	int index_nr;
@@ -15,6 +18,8 @@ struct nvkm_event {
 	spinlock_t list_lock;
 	struct list_head list;
 	int *refs;
+
+	struct list_head ntfy;
 };
 
 struct nvkm_event_func {
@@ -25,11 +30,42 @@ struct nvkm_event_func {
 	void (*fini)(struct nvkm_event *, int type, int index);
 };
 
-int  nvkm_event_init(const struct nvkm_event_func *func, int types_nr,
+int  nvkm_event_init(const struct nvkm_event_func *func, struct nvkm_subdev *, int types_nr,
 		     int index_nr, struct nvkm_event *);
 void nvkm_event_fini(struct nvkm_event *);
 void nvkm_event_get(struct nvkm_event *, u32 types, int index);
 void nvkm_event_put(struct nvkm_event *, u32 types, int index);
 void nvkm_event_send(struct nvkm_event *, u32 types, int index,
 		     void *data, u32 size);
+
+#define NVKM_EVENT_KEEP 0
+#define NVKM_EVENT_DROP 1
+struct nvkm_event_ntfy;
+typedef int (*nvkm_event_func)(struct nvkm_event_ntfy *, u32 bits);
+
+struct nvkm_event_ntfy {
+	struct nvkm_event *event;
+	int id;
+	u32 bits;
+	bool wait;
+	nvkm_event_func func;
+
+	atomic_t allowed;
+	bool running;
+
+	struct list_head head;
+};
+
+void nvkm_event_ntfy(struct nvkm_event *, int id, u32 bits);
+bool nvkm_event_ntfy_valid(struct nvkm_event *, int id, u32 bits);
+void nvkm_event_ntfy_add(struct nvkm_event *, int id, u32 bits, bool wait, nvkm_event_func,
+			 struct nvkm_event_ntfy *);
+void nvkm_event_ntfy_del(struct nvkm_event_ntfy *);
+void nvkm_event_ntfy_allow(struct nvkm_event_ntfy *);
+void nvkm_event_ntfy_block(struct nvkm_event_ntfy *);
+
+typedef int (*nvkm_uevent_func)(struct nvkm_object *, u64 token, u32 bits);
+
+int nvkm_uevent_new(const struct nvkm_oclass *, void *argv, u32 argc, struct nvkm_object **);
+int nvkm_uevent_add(struct nvkm_uevent *, struct nvkm_event *, int id, u32 bits, nvkm_uevent_func);
 #endif
diff --git a/drivers/gpu/drm/nouveau/include/nvkm/core/object.h b/drivers/gpu/drm/nouveau/include/nvkm/core/object.h
index 7efcd5d2f2ff..ed1f66360782 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/core/object.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/core/object.h
@@ -4,6 +4,7 @@
 #include <core/oclass.h>
 struct nvkm_event;
 struct nvkm_gpuobj;
+struct nvkm_uevent;
 
 struct nvkm_object {
 	const struct nvkm_object_func *func;
@@ -43,6 +44,7 @@ struct nvkm_object_func {
 	int (*bind)(struct nvkm_object *, struct nvkm_gpuobj *, int align,
 		    struct nvkm_gpuobj **);
 	int (*sclass)(struct nvkm_object *, int index, struct nvkm_oclass *);
+	int (*uevent)(struct nvkm_object *, void *argv, u32 argc, struct nvkm_uevent *);
 };
 
 void nvkm_object_ctor(const struct nvkm_object_func *,