drm/amdgpu: Add amdgpu_find_mm_node()

Replace some commonly repeated code with a function.

v2: Use amdgpu_find_mm_node() in amdgpu_ttm_io_mem_pfn()

Signed-off-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 27 insertions, 22 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 382c0ae0561e..51eacefadea1 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -291,7 +291,24 @@ static uint64_t amdgpu_mm_node_addr(struct ttm_buffer_object *bo,
 }
 
 /**
- * amdgpu_ttm_copy_mem_to_mem - Helper function for copy
+ * amdgpu_find_mm_node - Helper function finds the drm_mm_node
+ *  corresponding to @offset. It also modifies the offset to be
+ *  within the drm_mm_node returned
+ */
+static struct drm_mm_node *amdgpu_find_mm_node(struct ttm_mem_reg *mem,
+                                               unsigned long *offset)
+{
+        struct drm_mm_node *mm_node = mem->mm_node;
+
+        while (*offset >= (mm_node->size << PAGE_SHIFT)) {
+                *offset -= (mm_node->size << PAGE_SHIFT);
+                ++mm_node;
+        }
+        return mm_node;
+}
+
+/**
+ * amdgpu_copy_ttm_mem_to_mem - Helper function for copy
  *
  * The function copies @size bytes from {src->mem + src->offset} to
  * {dst->mem + dst->offset}. src->bo and dst->bo could be same BO for a
@@ -320,21 +337,13 @@ int amdgpu_ttm_copy_mem_to_mem(struct amdgpu_device *adev,
                 return -EINVAL;
         }
 
-        src_mm = src->mem->mm_node;
-        while (src->offset >= (src_mm->size << PAGE_SHIFT)) {
-                src->offset -= (src_mm->size << PAGE_SHIFT);
-                ++src_mm;
-        }
+        src_mm = amdgpu_find_mm_node(src->mem, &src->offset);
         src_node_start = amdgpu_mm_node_addr(src->bo, src_mm, src->mem) +
                                              src->offset;
         src_node_size = (src_mm->size << PAGE_SHIFT) - src->offset;
         src_page_offset = src_node_start & (PAGE_SIZE - 1);
 
-        dst_mm = dst->mem->mm_node;
-        while (dst->offset >= (dst_mm->size << PAGE_SHIFT)) {
-                dst->offset -= (dst_mm->size << PAGE_SHIFT);
-                ++dst_mm;
-        }
+        dst_mm = amdgpu_find_mm_node(dst->mem, &dst->offset);
         dst_node_start = amdgpu_mm_node_addr(dst->bo, dst_mm, dst->mem) +
                                              dst->offset;
         dst_node_size = (dst_mm->size << PAGE_SHIFT) - dst->offset;
@@ -654,13 +663,12 @@ static void amdgpu_ttm_io_mem_free(struct ttm_bo_device *bdev, struct ttm_mem_re
 static unsigned long amdgpu_ttm_io_mem_pfn(struct ttm_buffer_object *bo,
                                            unsigned long page_offset)
 {
-        struct drm_mm_node *mm = bo->mem.mm_node;
-        uint64_t size = mm->size;
-        uint64_t offset = page_offset;
+        struct drm_mm_node *mm;
+        unsigned long offset = (page_offset << PAGE_SHIFT);
 
-        page_offset = do_div(offset, size);
-        mm += offset;
-        return (bo->mem.bus.base >> PAGE_SHIFT) + mm->start + page_offset;
+        mm = amdgpu_find_mm_node(&bo->mem, &offset);
+        return (bo->mem.bus.base >> PAGE_SHIFT) + mm->start +
+                (offset >> PAGE_SHIFT);
 }
 
 /*
@@ -1216,7 +1224,7 @@ static int amdgpu_ttm_access_memory(struct ttm_buffer_object *bo,
 {
         struct amdgpu_bo *abo = ttm_to_amdgpu_bo(bo);
         struct amdgpu_device *adev = amdgpu_ttm_adev(abo->tbo.bdev);
-        struct drm_mm_node *nodes = abo->tbo.mem.mm_node;
+        struct drm_mm_node *nodes;
         uint32_t value = 0;
         int ret = 0;
         uint64_t pos;
@@ -1225,10 +1233,7 @@ static int amdgpu_ttm_access_memory(struct ttm_buffer_object *bo,
         if (bo->mem.mem_type != TTM_PL_VRAM)
                 return -EIO;
 
-        while (offset >= (nodes->size << PAGE_SHIFT)) {
-                offset -= nodes->size << PAGE_SHIFT;
-                ++nodes;
-        }
+        nodes = amdgpu_find_mm_node(&abo->tbo.mem, &offset);
         pos = (nodes->start << PAGE_SHIFT) + offset;
 
         while (len && pos < adev->mc.mc_vram_size) {