4 files changed, 42 insertions, 14 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/Kconfig b/drivers/gpu/drm/amd/amdgpu/Kconfig
index b30fcfa4b1f2..7335c0420c70 100644
--- a/drivers/gpu/drm/amd/amdgpu/Kconfig
+++ b/drivers/gpu/drm/amd/amdgpu/Kconfig
@@ -15,3 +15,13 @@ config DRM_AMDGPU_USERPTR
         help
           This option selects CONFIG_MMU_NOTIFIER if it isn't already
           selected to enabled full userptr support.
+
+config DRM_AMDGPU_GART_DEBUGFS
+        bool "Allow GART access through debugfs"
+        depends on DRM_AMDGPU
+        depends on DEBUG_FS
+        default n
+        help
+          Selecting this option creates a debugfs file to inspect the mapped
+          pages. Uses more memory for housekeeping, enable only for debugging.
+
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index e6f7bad735cc..b9a6fe9a2a31 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -611,7 +611,9 @@ struct amdgpu_gart {
         unsigned                        num_gpu_pages;
         unsigned                        num_cpu_pages;
         unsigned                        table_size;
+#ifdef CONFIG_DRM_AMDGPU_GART_DEBUGFS
         struct page                     **pages;
+#endif
         bool                            ready;
         const struct amdgpu_gart_funcs *gart_funcs;
 };
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c
index a13603abed07..921bce2df0b0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gart.c
@@ -238,17 +238,17 @@ void amdgpu_gart_unbind(struct amdgpu_device *adev, unsigned offset,
         t = offset / AMDGPU_GPU_PAGE_SIZE;
         p = t / (PAGE_SIZE / AMDGPU_GPU_PAGE_SIZE);
         for (i = 0; i < pages; i++, p++) {
-                if (adev->gart.pages[p]) {
-                        adev->gart.pages[p] = NULL;
-                        page_base = adev->dummy_page.addr;
-                        if (!adev->gart.ptr)
-                                continue;
+#ifdef CONFIG_AMDGPU_GART_DEBUGFS
+                adev->gart.pages[p] = NULL;
+#endif
+                page_base = adev->dummy_page.addr;
+                if (!adev->gart.ptr)
+                        continue;
 
-                        for (j = 0; j < (PAGE_SIZE / AMDGPU_GPU_PAGE_SIZE); j++, t++) {
-                                amdgpu_gart_set_pte_pde(adev, adev->gart.ptr,
-                                                        t, page_base, flags);
-                                page_base += AMDGPU_GPU_PAGE_SIZE;
-                        }
+                for (j = 0; j < (PAGE_SIZE / AMDGPU_GPU_PAGE_SIZE); j++, t++) {
+                        amdgpu_gart_set_pte_pde(adev, adev->gart.ptr,
+                                                t, page_base, flags);
+                        page_base += AMDGPU_GPU_PAGE_SIZE;
                 }
         }
         mb();
@@ -286,7 +286,9 @@ int amdgpu_gart_bind(struct amdgpu_device *adev, unsigned offset,
         p = t / (PAGE_SIZE / AMDGPU_GPU_PAGE_SIZE);
 
         for (i = 0; i < pages; i++, p++) {
+#ifdef CONFIG_AMDGPU_GART_DEBUGFS
                 adev->gart.pages[p] = pagelist[i];
+#endif
                 if (adev->gart.ptr) {
                         page_base = dma_addr[i];
                         for (j = 0; j < (PAGE_SIZE / AMDGPU_GPU_PAGE_SIZE); j++, t++) {
@@ -312,9 +314,9 @@ int amdgpu_gart_init(struct amdgpu_device *adev)
 {
         int r;
 
-        if (adev->gart.pages) {
+        if (adev->dummy_page.page)
                 return 0;
-        }
+
         /* We need PAGE_SIZE >= AMDGPU_GPU_PAGE_SIZE */
         if (PAGE_SIZE < AMDGPU_GPU_PAGE_SIZE) {
                 DRM_ERROR("Page size is smaller than GPU page size!\n");
@@ -328,12 +330,16 @@ int amdgpu_gart_init(struct amdgpu_device *adev)
         adev->gart.num_gpu_pages = adev->mc.gtt_size / AMDGPU_GPU_PAGE_SIZE;
         DRM_INFO("GART: num cpu pages %u, num gpu pages %u\n",
                  adev->gart.num_cpu_pages, adev->gart.num_gpu_pages);
+
+#ifdef CONFIG_AMDGPU_GART_DEBUGFS
         /* Allocate pages table */
         adev->gart.pages = vzalloc(sizeof(void *) * adev->gart.num_cpu_pages);
         if (adev->gart.pages == NULL) {
                 amdgpu_gart_fini(adev);
                 return -ENOMEM;
         }
+#endif
+
         return 0;
 }
 
@@ -346,13 +352,14 @@ int amdgpu_gart_init(struct amdgpu_device *adev)
  */
 void amdgpu_gart_fini(struct amdgpu_device *adev)
 {
-        if (adev->gart.pages && adev->gart.ready) {
+        if (adev->gart.ready) {
                 /* unbind pages */
                 amdgpu_gart_unbind(adev, 0, adev->gart.num_cpu_pages);
         }
         adev->gart.ready = false;
+#ifdef CONFIG_AMDGPU_GART_DEBUGFS
         vfree(adev->gart.pages);
         adev->gart.pages = NULL;
-
+#endif
         amdgpu_dummy_page_fini(adev);
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 6f3369de232f..7a8bdfedff1d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1216,6 +1216,8 @@ static const struct file_operations amdgpu_ttm_vram_fops = {
         .llseek = default_llseek
 };
 
+#ifdef CONFIG_DRM_AMDGPU_GART_DEBUGFS
+
 static ssize_t amdgpu_ttm_gtt_read(struct file *f, char __user *buf,
                                    size_t size, loff_t *pos)
 {
@@ -1263,6 +1265,8 @@ static const struct file_operations amdgpu_ttm_gtt_fops = {
 
 #endif
 
+#endif
+
 static int amdgpu_ttm_debugfs_init(struct amdgpu_device *adev)
 {
 #if defined(CONFIG_DEBUG_FS)
@@ -1278,6 +1282,7 @@ static int amdgpu_ttm_debugfs_init(struct amdgpu_device *adev)
         i_size_write(ent->d_inode, adev->mc.mc_vram_size);
         adev->mman.vram = ent;
 
+#ifdef CONFIG_DRM_AMDGPU_GART_DEBUGFS
         ent = debugfs_create_file("amdgpu_gtt", S_IFREG | S_IRUGO, root,
                                   adev, &amdgpu_ttm_gtt_fops);
         if (IS_ERR(ent))
@@ -1285,6 +1290,7 @@ static int amdgpu_ttm_debugfs_init(struct amdgpu_device *adev)
         i_size_write(ent->d_inode, adev->mc.gtt_size);
         adev->mman.gtt = ent;
 
+#endif
         count = ARRAY_SIZE(amdgpu_ttm_debugfs_list);
 
 #ifdef CONFIG_SWIOTLB
@@ -1306,7 +1312,10 @@ static void amdgpu_ttm_debugfs_fini(struct amdgpu_device *adev)
         debugfs_remove(adev->mman.vram);
         adev->mman.vram = NULL;
 
+#ifdef CONFIG_DRM_AMDGPU_GART_DEBUGFS
         debugfs_remove(adev->mman.gtt);
         adev->mman.gtt = NULL;
 #endif
+
+#endif
 }