// SPDX-License-Identifier: GPL-2.0+
/* Copyright (C) 2015-2018 Broadcom */
/**
* DOC: V3D GEM BO management support
*
* Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
* GPU and the bus, allowing us to use shmem objects for our storage
* instead of CMA.
*
* Physically contiguous objects may still be imported to V3D, but the
* driver doesn't allocate physically contiguous objects on its own.
* Display engines requiring physically contiguous allocations should
* look into Mesa's "renderonly" support (as used by the Mesa pl111
* driver) for an example of how to integrate with V3D.
*
* Long term, we should support evicting pages from the MMU when under
* memory pressure (thus the v3d_bo_get_pages() refcounting), but
* that's not a high priority since our systems tend to not have swap.
*/
#include <linux/dma-buf.h>
#include <linux/pfn_t.h>
#include <linux/vmalloc.h>
#include "v3d_drv.h"
#include "uapi/drm/v3d_drm.h"
static enum drm_gem_object_status v3d_gem_status(struct drm_gem_object *obj)
{
struct v3d_bo *bo = to_v3d_bo(obj);
enum drm_gem_object_status res = 0;
if (bo->base.pages)
res |= DRM_GEM_OBJECT_RESIDENT;
return res;
}
/* Called DRM core on the last userspace/kernel unreference of the
* BO.
*/
void v3d_free_object(struct drm_gem_object *obj)
{
struct v3d_dev *v3d = to_v3d_dev(obj->dev);
struct v3d_bo *bo = to_v3d_bo(obj);
if (bo->vaddr)
v3d_put_bo_vaddr(bo);
v3d_mmu_remove_ptes(bo);
mutex_lock(&v3d->bo_lock);
v3d->bo_stats.num_allocated--;
v3d->bo_stats.pages_allocated -= obj->size >> V3D_MMU_PAGE_SHIFT;
mutex_unlock(&v3d->bo_lock);
spin_lock(&v3d->mm_lock);
drm_mm_remove_node(&bo->node);
spin_unlock(&v3d->mm_lock);
/* GPU execution may have dirtied any pages in the BO. */
bo->base.pages_mark_dirty_on_put = true;
drm_gem_shmem_free(&bo->base);
}
static const struct drm_gem_object_funcs v3d_gem_funcs = {
.free = v3d_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 = drm_gem_shmem_object_mmap,
.status = v3d_gem_status,
.vm_ops = &drm_gem_shmem_vm_ops,
};
/* gem_create_object function for allocating a BO struct and doing
* early setup.
*/
struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
{
struct v3d_bo *bo;
struct drm_gem_object *obj;
if (size == 0)
return ERR_PTR(-EINVAL);
bo = kzalloc(sizeof(*bo), GFP_KERNEL);
if (!bo)
return ERR_PTR(-ENOMEM);
obj = &bo->base.base;
obj->funcs = &v3d_gem_funcs;
bo->base.map_wc = true;
INIT_LIST_HEAD(&bo->unref_head);
return &bo->base.base;
}
static int
v3d_bo_create_finish(struct drm_gem_object *obj)
{
struct v3d_dev *v3d = to_v3d_dev(obj->dev);
struct v3d_bo *bo = to_v3d_bo(obj);
struct sg_table *sgt;
int ret;
/* So far we pin the BO in the MMU for its lifetime, so use
* shmem's helper for getting a lifetime sgt.
*/
sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
if (IS_ERR(sgt))
return PTR_ERR(sgt);
spin_lock(&v3d->mm_lock);
/* Allocate the object's space in the GPU's page tables.
* Inserting PTEs will happen later, but the offset is for the
* lifetime of the BO.
*/
ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
obj->size >> V3D_MMU_PAGE_SHIFT,
GMP_GRANULARITY >> V3D_MMU_PAGE_SHIFT, 0, 0);
spin_unlock(&v3d->mm_lock);
if (ret)
return ret;
/* Track stats for /debug/dri/n/bo_stats. */
mutex_lock(&v3d->bo_lock);
v3d->bo_stats.num_allocated++;
v3d->bo_stats.pages_allocated += obj->size >> V3D_MMU_PAGE_SHIFT;
mutex_unlock(&v3d->bo_lock);
v3d_mmu_insert_ptes(bo);
return 0;
}
struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
size_t unaligned_size)
{
struct drm_gem_shmem_object *shmem_obj;
struct v3d_bo *bo;
int ret;
shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
if (IS_ERR(shmem_obj))
return ERR_CAST(shmem_obj);
bo = to_v3d_bo(&shmem_obj->base);
bo->vaddr = NULL;
ret = v3d_bo_create_finish(&shmem_obj->base);
if (ret)
goto free_obj;
return bo;
free_obj:
drm_gem_shmem_free(shmem_obj);
return ERR_PTR(ret);
}
struct drm_gem_object *
v3d_prime_import_sg_table(struct drm_device *dev,
struct dma_buf_attachment *attach,
struct sg_table *sgt)
{
struct drm_gem_object *obj;
int ret;
obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
if (IS_ERR(obj))
return obj;
ret = v3d_bo_create_finish(obj);
if (ret) {
drm_gem_shmem_free(&to_v3d_bo(obj)->base);
return ERR_PTR(ret);
}
return obj;
}
void v3d_get_bo_vaddr(struct v3d_bo *bo)
{
struct drm_gem_shmem_object *obj = &bo->base;
bo->vaddr = vmap(obj->pages, obj->base.size >> PAGE_SHIFT, VM_MAP,
pgprot_writecombine(PAGE_KERNEL));
}
void v3d_put_bo_vaddr(struct v3d_bo *bo)
{
vunmap(bo->vaddr);
bo->vaddr = NULL;
}
int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_v3d_create_bo *args = data;
struct v3d_bo *bo = NULL;
int ret;
if (args->flags != 0) {
DRM_INFO("unknown create_bo flags: %d\n", args->flags);
return -EINVAL;
}
bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
if (IS_ERR(bo))
return PTR_ERR(bo);
args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT;
ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
drm_gem_object_put(&bo->base.base);
return ret;
}
int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_v3d_mmap_bo *args = data;
struct drm_gem_object *gem_obj;
if (args->flags != 0) {
DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
return -EINVAL;
}
gem_obj = drm_gem_object_lookup(file_priv, args->handle);
if (!gem_obj) {
DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
return -ENOENT;
}
args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
drm_gem_object_put(gem_obj);
return 0;
}
int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_v3d_get_bo_offset *args = data;
struct drm_gem_object *gem_obj;
struct v3d_bo *bo;
gem_obj = drm_gem_object_lookup(file_priv, args->handle);
if (!gem_obj) {
DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
return -ENOENT;
}
bo = to_v3d_bo(gem_obj);
args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT;
drm_gem_object_put(gem_obj);
return 0;
}
int
v3d_wait_bo_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
int ret;
struct drm_v3d_wait_bo *args = data;
ktime_t start = ktime_get();
u64 delta_ns;
unsigned long timeout_jiffies =
nsecs_to_jiffies_timeout(args->timeout_ns);
if (args->pad != 0)
return -EINVAL;
ret = drm_gem_dma_resv_wait(file_priv, args->handle,
true, timeout_jiffies);
/* Decrement the user's timeout, in case we got interrupted
* such that the ioctl will be restarted.
*/
delta_ns = ktime_to_ns(ktime_sub(ktime_get(), start));
if (delta_ns < args->timeout_ns)
args->timeout_ns -= delta_ns;
else
args->timeout_ns = 0;
/* Asked to wait beyond the jiffy/scheduler precision? */
if (ret == -ETIME && args->timeout_ns)
ret = -EAGAIN;
return ret;
}
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