drm/exynos: add iommu support for exynos drm framework

Changelog v4:
- fix condition to drm_iommu_detach_device funtion.

Changelog v3:
- add dma_parms->max_segment_size setting of drm_device->dev.
- use devm_kzalloc instead of kzalloc.

Changelog v2:
- fix iommu attach condition.
  . check archdata.dma_ops of drm device instead of
    subdrv device's one.
- code clean to exynos_drm_iommu.c file.
  . remove '#ifdef CONFIG_ARM_DMA_USE_IOMMU' from exynos_drm_iommu.c
    and add it to driver/gpu/drm/exynos/Kconfig.

Changelog v1:
This patch adds iommu support for exynos drm framework with dma mapping
api. In this patch, we used dma mapping api to allocate physical memory
and maps it with iommu table and removed some existing codes and added
new some codes for iommu support.

GEM allocation requires one device object to use dma mapping api so
this patch uses one iommu mapping for all sub drivers. In other words,
all sub drivers have same iommu mapping.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.h b/drivers/gpu/drm/exynos/exynos_drm_drv.h
index a342310..8c9f4b0 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.h
@@ -241,6 +241,13 @@ struct drm_exynos_file_private {
 
 /*
  * Exynos drm private structure.
+ *
+ * @da_start: start address to device address space.
+ *	with iommu, device address space starts from this address
+ *	otherwise default one.
+ * @da_space_size: size of device address space.
+ *	if 0 then default value is used for it.
+ * @da_space_order: order to device address space.
  */
 struct exynos_drm_private {
 	struct drm_fb_helper *fb_helper;
@@ -255,6 +262,10 @@ struct exynos_drm_private {
 	struct drm_crtc *crtc[MAX_CRTC];
 	struct drm_property *plane_zpos_property;
 	struct drm_property *crtc_mode_property;
+
+	unsigned long da_start;
+	unsigned long da_space_size;
+	unsigned long da_space_order;
 };
 
 /*