drm/exynos: add iommu support for hdmi driver

Changelog v2:
move iommu support feature to mixer side.
And below is Prathyush's comment.

According to the new IOMMU framework for exynos sysmmus,
the owner of the sysmmu-tv is mixer (which is the actual
device that does DMA) and not hdmi.
The mmu-master in sysmmu-tv node is set as below in exynos5250.dtsi
	sysmmu-tv {
		-
		mmu-master = <&mixer>;
	};

Changelog v1:
The iommu will be enabled when hdmi sub driver is probed and
will be disabled when removed.

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

4 files changed, 40 insertions, 1 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_hdmi.c b/drivers/gpu/drm/exynos/exynos_drm_hdmi.c
index c3b9e2b45185..2d11e70b601a 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_hdmi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_hdmi.c
@@ -346,9 +346,23 @@ static int hdmi_subdrv_probe(struct drm_device *drm_dev,
         ctx->hdmi_ctx->drm_dev = drm_dev;
         ctx->mixer_ctx->drm_dev = drm_dev;
 
+        if (mixer_ops->iommu_on)
+                mixer_ops->iommu_on(ctx->mixer_ctx->ctx, true);
+
         return 0;
 }
 
+static void hdmi_subdrv_remove(struct drm_device *drm_dev, struct device *dev)
+{
+        struct drm_hdmi_context *ctx;
+        struct exynos_drm_subdrv *subdrv = to_subdrv(dev);
+
+        ctx = get_ctx_from_subdrv(subdrv);
+
+        if (mixer_ops->iommu_on)
+                mixer_ops->iommu_on(ctx->mixer_ctx->ctx, false);
+}
+
 static int __devinit exynos_drm_hdmi_probe(struct platform_device *pdev)
 {
         struct device *dev = &pdev->dev;
@@ -368,6 +382,7 @@ static int __devinit exynos_drm_hdmi_probe(struct platform_device *pdev)
         subdrv->dev = dev;
         subdrv->manager = &hdmi_manager;
         subdrv->probe = hdmi_subdrv_probe;
+        subdrv->remove = hdmi_subdrv_remove;
 
         platform_set_drvdata(pdev, subdrv);
 
diff --git a/drivers/gpu/drm/exynos/exynos_drm_hdmi.h b/drivers/gpu/drm/exynos/exynos_drm_hdmi.h
index 2da5ffd3a059..54b522353e48 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_hdmi.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_hdmi.h
@@ -62,6 +62,7 @@ struct exynos_hdmi_ops {
 
 struct exynos_mixer_ops {
         /* manager */
+        int (*iommu_on)(void *ctx, bool enable);
         int (*enable_vblank)(void *ctx, int pipe);
         void (*disable_vblank)(void *ctx);
         void (*dpms)(void *ctx, int mode);
diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
index 2c115f8a62a3..c73f43874944 100644
--- a/drivers/gpu/drm/exynos/exynos_hdmi.c
+++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
@@ -74,6 +74,7 @@ struct hdmi_context {
         struct mutex                    hdmi_mutex;
 
         void __iomem                    *regs;
+        void                            *parent_ctx;
         int                             external_irq;
         int                             internal_irq;
 
@@ -84,7 +85,6 @@ struct hdmi_context {
         int cur_conf;
 
         struct hdmi_resources           res;
-        void                            *parent_ctx;
 
         int                             hpd_gpio;
 
diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c
index 0d3ed282376c..50100cfddf4e 100644
--- a/drivers/gpu/drm/exynos/exynos_mixer.c
+++ b/drivers/gpu/drm/exynos/exynos_mixer.c
@@ -36,6 +36,7 @@
 
 #include "exynos_drm_drv.h"
 #include "exynos_drm_hdmi.h"
+#include "exynos_drm_iommu.h"
 
 #define get_mixer_context(dev)  platform_get_drvdata(to_platform_device(dev))
 
@@ -80,6 +81,7 @@ enum mixer_version_id {
 
 struct mixer_context {
         struct device           *dev;
+        struct drm_device       *drm_dev;
         int                     pipe;
         bool                    interlace;
         bool                    powered;
@@ -90,6 +92,7 @@ struct mixer_context {
         struct mixer_resources  mixer_res;
         struct hdmi_win_data    win_data[MIXER_WIN_NR];
         enum mixer_version_id   mxr_ver;
+        void                    *parent_ctx;
 };
 
 struct mixer_drv_data {
@@ -665,6 +668,24 @@ static void mixer_win_reset(struct mixer_context *ctx)
         spin_unlock_irqrestore(&res->reg_slock, flags);
 }
 
+static int mixer_iommu_on(void *ctx, bool enable)
+{
+        struct exynos_drm_hdmi_context *drm_hdmi_ctx;
+        struct mixer_context *mdata = ctx;
+        struct drm_device *drm_dev;
+
+        drm_hdmi_ctx = mdata->parent_ctx;
+        drm_dev = drm_hdmi_ctx->drm_dev;
+
+        if (is_drm_iommu_supported(drm_dev)) {
+                if (enable)
+                        return drm_iommu_attach_device(drm_dev, mdata->dev);
+
+                drm_iommu_detach_device(drm_dev, mdata->dev);
+        }
+        return 0;
+}
+
 static void mixer_poweron(struct mixer_context *ctx)
 {
         struct mixer_resources *res = &ctx->mixer_res;
@@ -866,6 +887,7 @@ static void mixer_win_disable(void *ctx, int win)
 
 static struct exynos_mixer_ops mixer_ops = {
         /* manager */
+        .iommu_on               = mixer_iommu_on,
         .enable_vblank          = mixer_enable_vblank,
         .disable_vblank         = mixer_disable_vblank,
         .dpms                   = mixer_dpms,
@@ -1140,6 +1162,7 @@ static int __devinit mixer_probe(struct platform_device *pdev)
         }
 
         ctx->dev = &pdev->dev;
+        ctx->parent_ctx = (void *)drm_hdmi_ctx;
         drm_hdmi_ctx->ctx = (void *)ctx;
         ctx->vp_enabled = drv->is_vp_enabled;
         ctx->mxr_ver = drv->version;