drm/rockchip: gem: reorder pages if page chunk less than 8

Change-Id: I03a91d2f9c017086b3cb35edeaf6b7913b147b9b
Signed-off-by: Simon Xue <xxm@rock-chips.com>

drivers/gpu/drm/rockchip/rockchip_drm_gem.c

@@ -16,6 +16,13 @@
 #include "rockchip_drm_drv.h"
 #include "rockchip_drm_gem.h"
 
+struct page_info {
+	struct page *page;
+	struct list_head list;
+};
+
+#define PG_ROUND       8
+
 static int rockchip_gem_iommu_map(struct rockchip_gem_object *rk_obj)
 {
 	struct drm_device *drm = rk_obj->base.dev;
@@ -73,23 +80,119 @@ static int rockchip_gem_iommu_unmap(struct rockchip_gem_object *rk_obj)
 	return 0;
 }
 
+static void rockchip_gem_free_list(struct list_head lists[])
+{
+	struct page_info *info, *tmp_info;
+	int i;
+
+	for (i = 0; i < PG_ROUND; i++) {
+		list_for_each_entry_safe(info, tmp_info, &lists[i], list) {
+			list_del(&info->list);
+			kfree(info);
+		}
+	}
+}
+
 static int rockchip_gem_get_pages(struct rockchip_gem_object *rk_obj)
 {
 	struct drm_device *drm = rk_obj->base.dev;
 	int ret, i;
 	struct scatterlist *s;
+	unsigned int cur_page;
+	struct page **pages, **dst_pages;
+	int j;
+	int n_pages;
+	unsigned long chunk_pages;
+	unsigned long remain;
+	struct list_head lists[PG_ROUND];
+	dma_addr_t phys;
+	int end = 0;
+	unsigned int bit12_14;
+	unsigned int block_index[PG_ROUND] = {0};
+	struct page_info *info;
+	unsigned int maximum;
 
-	rk_obj->pages = drm_gem_get_pages(&rk_obj->base);
+	for (i = 0; i < PG_ROUND; i++)
-	if (IS_ERR(rk_obj->pages))
+		INIT_LIST_HEAD(&lists[i]);
-		return PTR_ERR(rk_obj->pages);
+
+	pages = drm_gem_get_pages(&rk_obj->base);
+	if (IS_ERR(pages))
+		return PTR_ERR(pages);
+
+	rk_obj->pages = pages;
 
 	rk_obj->num_pages = rk_obj->base.size >> PAGE_SHIFT;
 
+	n_pages = rk_obj->num_pages;
+
+	dst_pages = __vmalloc(sizeof(struct page *) * n_pages,
+			GFP_KERNEL | __GFP_HIGHMEM);
+	if (!dst_pages) {
+		ret = -ENOMEM;
+		goto err_put_pages;
+	}
+
+	cur_page = 0;
+	remain = n_pages;
+	/* look for the end of the current chunk */
+	while (remain) {
+		for (j = cur_page + 1; j < n_pages; ++j) {
+			if (page_to_pfn(pages[j]) !=
+				page_to_pfn(pages[j - 1]) + 1)
+				break;
+		}
+
+		chunk_pages = j - cur_page;
+		if (chunk_pages > 7) {
+			for (i = 0; i < chunk_pages; i++)
+				dst_pages[end + i] = pages[cur_page + i];
+			end += chunk_pages;
+		} else {
+			for (i = 0; i < chunk_pages; i++) {
+				info = kmalloc(sizeof(*info), GFP_KERNEL);
+				if (!info) {
+					ret = -ENOMEM;
+					goto err_put_list;
+				}
+
+				INIT_LIST_HEAD(&info->list);
+				info->page = pages[cur_page + i];
+				phys = page_to_phys(info->page);
+				bit12_14 = (phys >> 12) & 0x7;
+				list_add_tail(&info->list, &lists[bit12_14]);
+				block_index[bit12_14]++;
+			}
+		}
+
+		cur_page = j;
+		remain -= chunk_pages;
+	}
+
+	maximum = block_index[0];
+	for (i = 1; i < PG_ROUND; i++)
+		maximum = max(maximum, block_index[i]);
+
+	for (i = 0; i < maximum; i++) {
+		for (j = 0; j < PG_ROUND; j++) {
+			if (!list_empty(&lists[j])) {
+				struct page_info *info;
+
+				info = list_first_entry(&lists[j],
+							struct page_info, list);
+				dst_pages[end++] = info->page;
+				list_del(&info->list);
+				kfree(info);
+			}
+		}
+	}
+
+	DRM_DEBUG_KMS("%s, %d, end = %d, n_pages = %d\n", __func__, __LINE__,
+			end, n_pages);
 	rk_obj->sgt = drm_prime_pages_to_sg(rk_obj->base.dev,
-					    rk_obj->pages, rk_obj->num_pages);
+					    dst_pages, rk_obj->num_pages);
 	if (IS_ERR(rk_obj->sgt)) {
 		ret = PTR_ERR(rk_obj->sgt);
-		goto err_put_pages;
+		goto err_put_list;
 	}
 
 	/*
@@ -104,8 +207,13 @@ static int rockchip_gem_get_pages(struct rockchip_gem_object *rk_obj)
 
 	dma_sync_sgtable_for_device(drm->dev, rk_obj->sgt, DMA_TO_DEVICE);
 
+	kvfree(pages);
+
 	return 0;
 
+err_put_list:
+	rockchip_gem_free_list(lists);
+	kvfree(dst_pages);
 err_put_pages:
 	drm_gem_put_pages(&rk_obj->base, rk_obj->pages, false, false);
 	return ret;