drm/nouveau/fault: add infrastructure to support fault buffers

GPU-specific support will be added separately.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/include/nvkm/subdev/fault.h

@@ -3,6 +3,12 @@
 #include <core/subdev.h>
 
 struct nvkm_fault {
+	const struct nvkm_fault_func *func;
 	struct nvkm_subdev subdev;
+
+	struct nvkm_fault_buffer *buffer[1];
+	int buffer_nr;
+
+	struct nvkm_event event;
 };
 #endif

drivers/gpu/drm/nouveau/nvkm/subdev/fault/Kbuild

+nvkm-y += nvkm/subdev/fault/base.o

drivers/gpu/drm/nouveau/nvkm/subdev/fault/base.c

+/*
+ * Copyright 2018 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "priv.h"
+
+#include <core/memory.h>
+#include <core/notify.h>
+#include <subdev/bar.h>
+#include <subdev/mmu.h>
+
+static void
+nvkm_fault_ntfy_fini(struct nvkm_event *event, int type, int index)
+{
+	struct nvkm_fault *fault = container_of(event, typeof(*fault), event);
+	fault->func->buffer.fini(fault->buffer[index]);
+}
+
+static void
+nvkm_fault_ntfy_init(struct nvkm_event *event, int type, int index)
+{
+	struct nvkm_fault *fault = container_of(event, typeof(*fault), event);
+	fault->func->buffer.init(fault->buffer[index]);
+}
+
+static int
+nvkm_fault_ntfy_ctor(struct nvkm_object *object, void *argv, u32 argc,
+		     struct nvkm_notify *notify)
+{
+	struct nvkm_fault_buffer *buffer = nvkm_fault_buffer(object);
+	if (argc == 0) {
+		notify->size  = 0;
+		notify->types = 1;
+		notify->index = buffer->id;
+		return 0;
+	}
+	return -ENOSYS;
+}
+
+static const struct nvkm_event_func
+nvkm_fault_ntfy = {
+	.ctor = nvkm_fault_ntfy_ctor,
+	.init = nvkm_fault_ntfy_init,
+	.fini = nvkm_fault_ntfy_fini,
+};
+
+static void
+nvkm_fault_intr(struct nvkm_subdev *subdev)
+{
+	struct nvkm_fault *fault = nvkm_fault(subdev);
+	return fault->func->intr(fault);
+}
+
+static int
+nvkm_fault_fini(struct nvkm_subdev *subdev, bool suspend)
+{
+	struct nvkm_fault *fault = nvkm_fault(subdev);
+	if (fault->func->fini)
+		fault->func->fini(fault);
+	return 0;
+}
+
+static int
+nvkm_fault_init(struct nvkm_subdev *subdev)
+{
+	struct nvkm_fault *fault = nvkm_fault(subdev);
+	if (fault->func->init)
+		fault->func->init(fault);
+	return 0;
+}
+
+static int
+nvkm_fault_oneinit_buffer(struct nvkm_fault *fault, int id)
+{
+	struct nvkm_subdev *subdev = &fault->subdev;
+	struct nvkm_device *device = subdev->device;
+	struct nvkm_vmm *bar2 = nvkm_bar_bar2_vmm(device);
+	struct nvkm_fault_buffer *buffer;
+	int ret;
+
+	if (!(buffer = kzalloc(sizeof(*buffer), GFP_KERNEL)))
+		return -ENOMEM;
+	buffer->fault = fault;
+	buffer->id = id;
+	buffer->entries = fault->func->buffer.entries(buffer);
+	fault->buffer[id] = buffer;
+
+	nvkm_debug(subdev, "buffer %d: %d entries\n", id, buffer->entries);
+
+	ret = nvkm_memory_new(device, NVKM_MEM_TARGET_INST, buffer->entries *
+			      fault->func->buffer.entry_size, 0x1000, true,
+			      &buffer->mem);
+	if (ret)
+		return ret;
+
+	ret = nvkm_vmm_get(bar2, 12, nvkm_memory_size(buffer->mem),
+			   &buffer->vma);
+	if (ret)
+		return ret;
+
+	return nvkm_memory_map(buffer->mem, 0, bar2, buffer->vma, NULL, 0);
+}
+
+static int
+nvkm_fault_oneinit(struct nvkm_subdev *subdev)
+{
+	struct nvkm_fault *fault = nvkm_fault(subdev);
+	int ret, i;
+
+	for (i = 0; i < ARRAY_SIZE(fault->buffer); i++) {
+		if (i < fault->func->buffer.nr) {
+			ret = nvkm_fault_oneinit_buffer(fault, i);
+			if (ret)
+				return ret;
+			fault->buffer_nr = i + 1;
+		}
+	}
+
+	return nvkm_event_init(&nvkm_fault_ntfy, 1, fault->buffer_nr,
+			       &fault->event);
+}
+
+static void *
+nvkm_fault_dtor(struct nvkm_subdev *subdev)
+{
+	struct nvkm_vmm *bar2 = nvkm_bar_bar2_vmm(subdev->device);
+	struct nvkm_fault *fault = nvkm_fault(subdev);
+	int i;
+
+	nvkm_event_fini(&fault->event);
+
+	for (i = 0; i < fault->buffer_nr; i++) {
+		if (fault->buffer[i]) {
+			nvkm_vmm_put(bar2, &fault->buffer[i]->vma);
+			nvkm_memory_unref(&fault->buffer[i]->mem);
+			kfree(fault->buffer[i]);
+		}
+	}
+
+	return fault;
+}
+
+static const struct nvkm_subdev_func
+nvkm_fault = {
+	.dtor = nvkm_fault_dtor,
+	.oneinit = nvkm_fault_oneinit,
+	.init = nvkm_fault_init,
+	.fini = nvkm_fault_fini,
+	.intr = nvkm_fault_intr,
+};
+
+int
+nvkm_fault_new_(const struct nvkm_fault_func *func, struct nvkm_device *device,
+		int index, struct nvkm_fault **pfault)
+{
+	struct nvkm_fault *fault;
+	if (!(fault = *pfault = kzalloc(sizeof(*fault), GFP_KERNEL)))
+		return -ENOMEM;
+	nvkm_subdev_ctor(&nvkm_fault, device, index, &fault->subdev);
+	fault->func = func;
+	return 0;
+}

drivers/gpu/drm/nouveau/nvkm/subdev/fault/priv.h

+#ifndef __NVKM_FAULT_PRIV_H__
+#define __NVKM_FAULT_PRIV_H__
+#define nvkm_fault_buffer(p) container_of((p), struct nvkm_fault_buffer, object)
+#define nvkm_fault(p) container_of((p), struct nvkm_fault, subdev)
+#include <subdev/fault.h>
+
+#include <core/event.h>
+#include <core/object.h>
+
+struct nvkm_fault_buffer {
+	struct nvkm_object object;
+	struct nvkm_fault *fault;
+	int id;
+	int entries;
+	struct nvkm_memory *mem;
+	struct nvkm_vma *vma;
+};
+
+int nvkm_fault_new_(const struct nvkm_fault_func *, struct nvkm_device *,
+		    int index, struct nvkm_fault **);
+
+struct nvkm_fault_func {
+	void (*init)(struct nvkm_fault *);
+	void (*fini)(struct nvkm_fault *);
+	void (*intr)(struct nvkm_fault *);
+	struct {
+		int nr;
+		u32 entry_size;
+		u32 (*entries)(struct nvkm_fault_buffer *);
+		void (*init)(struct nvkm_fault_buffer *);
+		void (*fini)(struct nvkm_fault_buffer *);
+	} buffer;
+};
+#endif