diff options
| author | Thierry Reding <treding@nvidia.com> | 2019-10-28 13:37:13 +0100 |
|---|---|---|
| committer | Thierry Reding <treding@nvidia.com> | 2019-10-29 15:04:35 +0100 |
| commit | af1cbfb9bf0fe079ca328231451fd4db8b3eafec (patch) | |
| tree | 136ba6066a4ed6b84181e5850e76dc751aeda168 /drivers/gpu/drm/tegra/gem.c | |
| parent | b78e70c04c149299bd210759d7c7af7c86b89ca8 (diff) | |
gpu: host1x: Support DMA mapping of buffers
If host1x_bo_pin() returns an SG table, create a DMA mapping for the
buffer. For buffers that the host1x client has already mapped itself,
host1x_bo_pin() returns NULL and the existing DMA address is used.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Diffstat (limited to 'drivers/gpu/drm/tegra/gem.c')
| -rw-r--r-- | drivers/gpu/drm/tegra/gem.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c index 564ef60f67c2..746dae32c484 100644 --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -34,9 +34,19 @@ static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo, struct sg_table *sgt; int err; - if (phys) + /* + * If we've manually mapped the buffer object through the IOMMU, make + * sure to return the IOVA address of our mapping. + */ + if (phys && obj->mm) { *phys = obj->iova; + return NULL; + } + /* + * If we don't have a mapping for this buffer yet, return an SG table + * so that host1x can do the mapping for us via the DMA API. + */ sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) return ERR_PTR(-ENOMEM); @@ -62,8 +72,10 @@ free: static void tegra_bo_unpin(struct device *dev, struct sg_table *sgt) { - sg_free_table(sgt); - kfree(sgt); + if (sgt) { + sg_free_table(sgt); + kfree(sgt); + } } static void *tegra_bo_mmap(struct host1x_bo *bo) |