[PATCH] drm/exynos: consider no iommu support to console framebuffer

[Inki Dae]

This patch considers no iommu support to kernel space mapping
of console framebuffer.

Without iommu, we get physical address instead of device address
after dma_alloc_attrs function is called. So we should consider
the case without iommu when it maps console framebuffer with
kernel space.

Signed-off-by: Inki Dae <inki.dae at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_fbdev.c |   20 +++++++++++++++++---
 1 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c 
b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index f433eb7..ae0607f 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -34,6 +34,7 @@
 #include "exynos_drm_drv.h"
 #include "exynos_drm_fb.h"
 #include "exynos_drm_gem.h"
+#include "exynos_drm_iommu.h"

 #define MAX_CONNECTOR          4
 #define PREFERRED_BPP          32
@@ -111,9 +112,18 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper 
*helper,

        /* map pages with kernel virtual space. */
        if (!buffer->kvaddr) {
-               unsigned int nr_pages = buffer->size >> PAGE_SHIFT;
-               buffer->kvaddr = vmap(buffer->pages, nr_pages, VM_MAP,
+               if (is_drm_iommu_supported(dev)) {
+                       unsigned int nr_pages = buffer->size >> PAGE_SHIFT;
+
+                       buffer->kvaddr = vmap(buffer->pages, nr_pages, VM_MAP,
                                        pgprot_writecombine(PAGE_KERNEL));
+               } else {
+                       phys_addr_t dma_addr = buffer->dma_addr;
+                       if (dma_addr)
+                               buffer->kvaddr = phys_to_virt(dma_addr);
+                       else
+                               buffer->kvaddr = (void __iomem *)NULL;
+               }
                if (!buffer->kvaddr) {
                        DRM_ERROR("failed to map pages to kernel space.\n");
                        return -EIO;
@@ -128,8 +138,12 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper 
*helper,

        dev->mode_config.fb_base = (resource_size_t)buffer->dma_addr;
        fbi->screen_base = buffer->kvaddr + offset;
-       fbi->fix.smem_start = (unsigned long)
+       if (is_drm_iommu_supported(dev))
+               fbi->fix.smem_start = (unsigned long)
                        (page_to_phys(sg_page(buffer->sgt->sgl)) + offset);
+       else
+               fbi->fix.smem_start = (unsigned long)buffer->dma_addr;
+
        fbi->screen_size = size;
        fbi->fix.smem_len = size;

-- 
1.7.4.1