drm/tegra: Refactor IOMMU attach/detach
Attaching to and detaching from an IOMMU uses the same code sequence in
every driver, so factor it out into separate helpers.
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 7afe2f6..181e82c 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -1114,6 +1114,52 @@
return 0;
}
+struct iommu_group *host1x_client_iommu_attach(struct host1x_client *client,
+ bool shared)
+{
+ struct drm_device *drm = dev_get_drvdata(client->parent);
+ struct tegra_drm *tegra = drm->dev_private;
+ struct iommu_group *group = NULL;
+ int err;
+
+ if (tegra->domain) {
+ group = iommu_group_get(client->dev);
+ if (!group) {
+ dev_err(client->dev, "failed to get IOMMU group\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (!shared || (shared && (group != tegra->group))) {
+ err = iommu_attach_group(tegra->domain, group);
+ if (err < 0) {
+ iommu_group_put(group);
+ return ERR_PTR(err);
+ }
+
+ if (shared && !tegra->group)
+ tegra->group = group;
+ }
+ }
+
+ return group;
+}
+
+void host1x_client_iommu_detach(struct host1x_client *client,
+ struct iommu_group *group)
+{
+ struct drm_device *drm = dev_get_drvdata(client->parent);
+ struct tegra_drm *tegra = drm->dev_private;
+
+ if (group) {
+ if (group == tegra->group) {
+ iommu_detach_group(tegra->domain, group);
+ tegra->group = NULL;
+ }
+
+ iommu_group_put(group);
+ }
+}
+
void *tegra_drm_alloc(struct tegra_drm *tegra, size_t size, dma_addr_t *dma)
{
struct iova *alloc;