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, 85 insertions, 0 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_iommu.h b/drivers/gpu/drm/exynos/exynos_drm_iommu.h
new file mode 100644
index 000000000000..18a0ca190b98
--- /dev/null
+++ b/drivers/gpu/drm/exynos/exynos_drm_iommu.h
@@ -0,0 +1,85 @@
+/* exynos_drm_iommu.h
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ * Authoer: Inki Dae <inki.dae@samsung.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef _EXYNOS_DRM_IOMMU_H_
+#define _EXYNOS_DRM_IOMMU_H_
+
+#define EXYNOS_DEV_ADDR_START	0x20000000
+#define EXYNOS_DEV_ADDR_SIZE	0x40000000
+#define EXYNOS_DEV_ADDR_ORDER	0x4
+
+#ifdef CONFIG_DRM_EXYNOS_IOMMU
+
+int drm_create_iommu_mapping(struct drm_device *drm_dev);
+
+void drm_release_iommu_mapping(struct drm_device *drm_dev);
+
+int drm_iommu_attach_device(struct drm_device *drm_dev,
+				struct device *subdrv_dev);
+
+void drm_iommu_detach_device(struct drm_device *dev_dev,
+				struct device *subdrv_dev);
+
+static inline bool is_drm_iommu_supported(struct drm_device *drm_dev)
+{
+#ifdef CONFIG_ARM_DMA_USE_IOMMU
+	struct device *dev = drm_dev->dev;
+
+	return dev->archdata.mapping ? true : false;
+#else
+	return false;
+#endif
+}
+
+#else
+
+struct dma_iommu_mapping;
+static inline int drm_create_iommu_mapping(struct drm_device *drm_dev)
+{
+	return 0;
+}
+
+static inline void drm_release_iommu_mapping(struct drm_device *drm_dev)
+{
+}
+
+static inline int drm_iommu_attach_device(struct drm_device *drm_dev,
+						struct device *subdrv_dev)
+{
+	return 0;
+}
+
+static inline void drm_iommu_detach_device(struct drm_device *drm_dev,
+						struct device *subdrv_dev)
+{
+}
+
+static inline bool is_drm_iommu_supported(struct drm_device *drm_dev)
+{
+	return false;
+}
+
+#endif
+#endif