Anything relating to GEM object management is placed here. Nothing
particularly interesting here, given the implementation is based on
drm_gem_shmem_object, which is doing most of the work.
v2:
- Rename the driver (pancsf -> panthor)
- Change the license (GPL2 -> MIT + GPL2)
- Split the driver addition commit
- Document the code
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
---
drivers/gpu/drm/panthor/panthor_gem.c | 229 ++++++++++++++++++++++++++
drivers/gpu/drm/panthor/panthor_gem.h | 96 +++++++++++
2 files changed, 325 insertions(+)
create mode 100644 drivers/gpu/drm/panthor/panthor_gem.c
create mode 100644 drivers/gpu/drm/panthor/panthor_gem.h
diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c
new file mode 100644
index 000000000000..a441a68822ca
--- /dev/null
+++ b/drivers/gpu/drm/panthor/panthor_gem.c
@@ -0,0 +1,229 @@
+// SPDX-License-Identifier: GPL-2.0 or MIT
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@xxxxxxxxxx> */
+/* Copyright 2023 Collabora ltd. */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/dma-buf.h>
+#include <linux/dma-mapping.h>
+
+#include <drm/panthor_drm.h>
+
+#include "panthor_device.h"
+#include "panthor_gem.h"
+#include "panthor_mmu.h"
+
+static void panthor_gem_free_object(struct drm_gem_object *obj)
+{
+ struct panthor_gem_object *bo = to_panthor_bo(obj);
+
+ if (drm_WARN_ON(obj->dev, bo->va_node))
+ panthor_vm_free_va(bo->exclusive_vm, bo->va_node);
+
+ panthor_vm_put(bo->exclusive_vm);
+ drm_gem_free_mmap_offset(&bo->base.base);
+ mutex_destroy(&bo->gpuva_list_lock);
+ drm_gem_shmem_free(&bo->base);
+}
+
+/**
+ * panthor_gem_unmap_and_put() - Unmap and drop the reference on a GEM object
+ * @vm: VM to unmap the GEM from.
+ * @bo: GEM object to unmap/release.
+ * @gpu_va: GPU/MCU virtual address the GEM object was mapped at.
+ * @cpu_va: kernel mapping of the GEM object.
+ * Can be NULL if the GEM was not CPU mapped.
+ *
+ * Should be called to undo what was done in panthor_gem_create_and_map().
+ */
+void panthor_gem_unmap_and_put(struct panthor_vm *vm,
+ struct panthor_gem_object *bo,
+ u64 gpu_va, void *cpu_va)
+{
+ if (cpu_va) {
+ struct iosys_map map = IOSYS_MAP_INIT_VADDR(cpu_va);
+
+ drm_gem_vunmap_unlocked(&bo->base.base, &map);
+ }
+
+ drm_WARN_ON(bo->base.base.dev, panthor_vm_unmap_range(vm, gpu_va, bo->base.base.size));
+ panthor_vm_free_va(vm, bo->va_node);
+ bo->va_node = NULL;
+ drm_gem_object_put(&bo->base.base);
+}
+
+/**
+ * panthor_gem_create_and_map() - Create and map a GEM object to a VM
+ * @ptdev: Device.
+ * @vm: VM to map the GEM to.
+ * @bo_flags: Combination of drm_panthor_bo_flags flags.
+ * @vm_map_flags: Combination of drm_panthor_vm_bind_op_flags (only those
+ * that are related to map operations).
+ * @gpu_va: Pointer holding the GPU address assigned when mapping to the VM.
+ * If *gpu_va == PANTHOR_GEM_ALLOC_VA, a virtual address range will be allocated
+ * and the allocated address returned, otherwise *gpu_va is used directly.
+ * @cpu_va: Pointer holding the kernel CPU mapping. If NULL, the GEM object
+ * is not CPU-mapped.
+ *
+ * Return: A valid pointer in case of success, an ERR_PTR() otherwise.
+ */
+struct panthor_gem_object *
+panthor_gem_create_and_map(struct panthor_device *ptdev, struct panthor_vm *vm,
+ size_t size, u32 bo_flags, u32 vm_map_flags,
+ u64 *gpu_va, void **cpu_va)
+{
+ struct drm_gem_shmem_object *obj;
+ struct panthor_gem_object *bo;
+ int ret;
+
+ obj = drm_gem_shmem_create(&ptdev->base, size);
+ if (!obj)
+ return ERR_PTR(-ENOMEM);
+
+ bo = to_panthor_bo(&obj->base);
+ bo->flags = bo_flags;
+ bo->exclusive_vm = panthor_vm_get(vm);
+ bo->base.base.resv = panthor_vm_resv(vm);
+
+ if (*gpu_va == PANTHOR_GEM_ALLOC_VA) {
+ bo->va_node = panthor_vm_alloc_va(vm, obj->base.size);
+
+ if (IS_ERR(bo->va_node)) {
+ ret = PTR_ERR(bo->va_node);
+ bo->va_node = NULL;
+ goto err_put_obj;
+ }
+
+ *gpu_va = bo->va_node->start;
+ }
+
+ ret = panthor_vm_map_bo_range(vm, bo, 0, obj->base.size, *gpu_va, vm_map_flags);
+ if (ret)
+ goto err_put_obj;
+
+ if (cpu_va) {
+ struct iosys_map map;
+ int ret;
+
+ ret = drm_gem_vmap_unlocked(&obj->base, &map);
+ if (ret)
+ goto err_vm_unmap_range;
+
+ *cpu_va = map.vaddr;
+ }
+
+ return bo;
+
+err_vm_unmap_range:
+ panthor_vm_unmap_range(vm, *gpu_va, obj->base.size);
+
+err_put_obj:
+ drm_gem_object_put(&obj->base);
+ return ERR_PTR(ret);
+}
+
+static int panthor_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
+{
+ struct panthor_gem_object *bo = to_panthor_bo(obj);
+
+ /* Don't allow mmap on objects that have the NO_MMAP flag set. */
+ if (bo->flags & DRM_PANTHOR_BO_NO_MMAP)
+ return -EINVAL;
+
+ return drm_gem_shmem_object_mmap(obj, vma);
+}
+
+static struct dma_buf *
+panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
+{
+ /* We can't export GEMs that have an exclusive VM. */
+ if (to_panthor_bo(obj)->exclusive_vm)
+ return ERR_PTR(-EINVAL);
+
+ return drm_gem_prime_export(obj, flags);
+}
+
+static const struct drm_gem_object_funcs panthor_gem_funcs = {
+ .free = panthor_gem_free_object,
+ .print_info = drm_gem_shmem_object_print_info,
+ .pin = drm_gem_shmem_object_pin,
+ .unpin = drm_gem_shmem_object_unpin,
+ .get_sg_table = drm_gem_shmem_object_get_sg_table,
+ .vmap = drm_gem_shmem_object_vmap,
+ .vunmap = drm_gem_shmem_object_vunmap,
+ .mmap = panthor_gem_mmap,
+ .export = panthor_gem_prime_export,
+ .vm_ops = &drm_gem_shmem_vm_ops,
+};
+
+/**
+ * panthor_gem_create_object - Implementation of driver->gem_create_object.
+ * @dev: DRM device
+ * @size: Size in bytes of the memory the object will reference
+ *
+ * This lets the GEM helpers allocate object structs for us, and keep
+ * our BO stats correct.
+ */
+struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t size)
+{
+ struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
+ struct panthor_gem_object *obj;
+
+ obj = kzalloc(sizeof(*obj), GFP_KERNEL);
+ if (!obj)
+ return ERR_PTR(-ENOMEM);
+
+ obj->base.base.funcs = &panthor_gem_funcs;
+ obj->base.map_wc = !ptdev->coherent;
+ mutex_init(&obj->gpuva_list_lock);
+ drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
+
+ return &obj->base.base;
+}
+
+/**
+ * panthor_gem_create_with_handle() - Create a GEM object and attach it to a handle.
+ * @file: DRM file.
+ * @ddev: DRM device.
+ * @exclusive_vm: Exclusive VM. Not NULL if the GEM object can't be shared.
+ * @size: Size of the GEM object to allocate.
+ * @flags: Combination of drm_panthor_bo_flags flags.
+ * @handle: Pointer holding the handle pointing to the new GEM object.
+ *
+ * Return: A valid pointer on success, an ERR_PTR() otherwise.
+ */
+struct panthor_gem_object *
+panthor_gem_create_with_handle(struct drm_file *file,
+ struct drm_device *ddev,
+ struct panthor_vm *exclusive_vm,
+ size_t size,
+ u32 flags, u32 *handle)
+{
+ int ret;
+ struct drm_gem_shmem_object *shmem;
+ struct panthor_gem_object *bo;
+
+ shmem = drm_gem_shmem_create(ddev, size);
+ if (IS_ERR(shmem))
+ return ERR_CAST(shmem);
+
+ bo = to_panthor_bo(&shmem->base);
+ bo->flags = flags;
+
+ if (exclusive_vm) {
+ bo->exclusive_vm = panthor_vm_get(exclusive_vm);
+ bo->base.base.resv = panthor_vm_resv(exclusive_vm);
+ }
+
+ /*
+ * Allocate an id of idr table where the obj is registered
+ * and handle has the id what user can see.
+ */
+ ret = drm_gem_handle_create(file, &shmem->base, handle);
+ /* drop reference from allocate - handle holds it now. */
+ drm_gem_object_put(&shmem->base);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return bo;
+}
diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
new file mode 100644
index 000000000000..07babadc7623
--- /dev/null
+++ b/drivers/gpu/drm/panthor/panthor_gem.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0 or MIT */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@xxxxxxxxxx> */
+/* Copyright 2023 Collabora ltd. */
+
+#ifndef __PANTHOR_GEM_H__
+#define __PANTHOR_GEM_H__
+
+#include <drm/drm_gem_shmem_helper.h>
+#include <drm/drm_mm.h>
+
+#include <linux/rwsem.h>
+
+struct panthor_vm;
+
+/**
+ * struct panthor_gem_object - Driver specific GEM object.
+ */
+struct panthor_gem_object {
+ /** @base: Inherit from drm_gem_shmem_object. */
+ struct drm_gem_shmem_object base;
+
+ /**
+ * @va_node: VA space allocated to this GEM.
+ *
+ * Should be NULL for all GEM objects managed by userspace.
+ *
+ * Not NULL when %PANTHOR_GEM_ALLOC_VA is passed as an address, in
+ * which case the GEM logic will auto-allocate a VA range before mapping
+ * to the VM.
+ *
+ * @exclusive_vm must be != NULL.
+ */
+ struct drm_mm_node *va_node;
+
+ /**
+ * @exclusive_vm: Exclusive VM this GEM object can be mapped to.
+ *
+ * If @exclusive_vm != NULL, any attempt to bind the GEM to a different
+ * VM will fail.
+ *
+ * All FW memory objects have this field set to the MCU VM.
+ */
+ struct panthor_vm *exclusive_vm;
+
+ /**
+ * @gpuva_list_lock: Custom GPUVA lock.
+ *
+ * Used to protect insertion of drm_gpuva elements to the
+ * drm_gem_object.gpuva.list list.
+ *
+ * We can't use the GEM resv for that, because drm_gpuva_link() is
+ * called in a dma-signaling path, where we're not allowed to take
+ * resv locks.
+ */
+ struct mutex gpuva_list_lock;
+
+ /** @flags: Combination of drm_panthor_bo_flags flags. */
+ u32 flags;
+};
+
+static inline
+struct panthor_gem_object *to_panthor_bo(struct drm_gem_object *obj)
+{
+ return container_of(to_drm_gem_shmem_obj(obj), struct panthor_gem_object, base);
+}
+
+struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t size);
+
+struct drm_gem_object *
+panthor_gem_prime_import_sg_table(struct drm_device *ddev,
+ struct dma_buf_attachment *attach,
+ struct sg_table *sgt);
+
+struct panthor_gem_object *
+panthor_gem_create_with_handle(struct drm_file *file,
+ struct drm_device *ddev,
+ struct panthor_vm *exclusive_vm,
+ size_t size,
+ u32 flags,
+ uint32_t *handle);
+
+void panthor_gem_unmap_and_put(struct panthor_vm *vm, struct panthor_gem_object *bo,
+ u64 gpu_va, void *cpu_va);
+
+/*
+ * PANTHOR_GEM_ALLOC_VA: Use this magic address when you want the GEM
+ * logic to auto-allocate the virtual address in the reserved kernel VA range.
+ */
+#define PANTHOR_GEM_ALLOC_VA ~0ull
+
+struct panthor_gem_object *
+panthor_gem_create_and_map(struct panthor_device *ptdev, struct panthor_vm *vm,
+ size_t size, u32 bo_flags, u32 vm_map_flags,
+ u64 *gpu_va, void **cpu_va);
+
+#endif /* __PANTHOR_GEM_H__ */
--
2.41.0
