pan/kmod: Add a backend for panthor

Panthor is a new kernel driver handling CSF-based GPUs. It's designed
around the new VM model where:

- VM management is all explicit (you get to choose where objects are
  mapped in the GPU VA space)
- synchronization is explicit too (there's not BO_WAIT, and we don't
  pass BOs around to serve as implicit deps)

We add a few panthor specific helpers (those exposed in panthor_kmod.h)
too:

- panthor_kmod_xxx_sync_point() are needed to make pan_kmod_bo_wait()
  work with the new synchronization/VM model
- panthor_kmod_get_flush_id() is exposing the LATEST_FLUSH_ID register
- panthor_kmod_vm_handle() is providing a way to query the VM handle
  attached to the pan_kmod_vm object (needed for a few panthor ioctls)

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Antonino Maniscalco <antonino.maniscalco@collabora.com>
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26358>

src/panfrost/lib/kmod/meson.build

@@ -21,6 +21,7 @@
 libpankmod_lib_files = files(
   'pan_kmod.c',
   'panfrost_kmod.c',
+  'panthor_kmod.c',
 )
 
 libpankmod_lib = static_library(

src/panfrost/lib/kmod/pan_kmod.c

@@ -11,6 +11,7 @@
 #include "pan_kmod.h"
 
 extern const struct pan_kmod_ops panfrost_kmod_ops;
+extern const struct pan_kmod_ops panthor_kmod_ops;
 
 static const struct {
    const char *name;
@@ -20,6 +21,10 @@ static const struct {
       "panfrost",
       &panfrost_kmod_ops,
    },
+   {
+      "panthor",
+      &panthor_kmod_ops,
+   },
 };
 
 static void *

src/panfrost/lib/kmod/pan_kmod.h

@@ -32,6 +32,8 @@
 #include "util/sparse_array.h"
 #include "util/u_atomic.h"
 
+#include "kmod/panthor_kmod.h"
+
 #if defined(__cplusplus)
 extern "C" {
 #endif

src/panfrost/lib/kmod/panthor_kmod.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright © 2023 Collabora, Ltd.
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#pragma once
+
+#include <stdint.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+struct drm_panthor_csif_info;
+
+struct pan_kmod_bo;
+struct pan_kmod_dev;
+struct pan_kmod_vm;
+
+int panthor_kmod_bo_attach_sync_point(struct pan_kmod_bo *bo,
+                                      uint32_t sync_handle,
+                                      uint64_t sync_point, bool written);
+int panthor_kmod_bo_get_sync_point(struct pan_kmod_bo *bo,
+                                   uint32_t *sync_handle, uint64_t *sync_point,
+                                   bool read_only);
+uint32_t panthor_kmod_vm_sync_handle(struct pan_kmod_vm *vm);
+uint64_t panthor_kmod_vm_sync_lock(struct pan_kmod_vm *vm);
+void panthor_kmod_vm_sync_unlock(struct pan_kmod_vm *vm,
+                                 uint64_t new_sync_point);
+uint32_t panthor_kmod_get_flush_id(const struct pan_kmod_dev *dev);
+
+const struct drm_panthor_csif_info *
+panthor_kmod_get_csif_props(const struct pan_kmod_dev *dev);
+
+#if defined(__cplusplus)
+} // extern "C"
+#endif