net: ethernet: mtk_wed: introduce mtk_wed_buf structure

Introduce mtk_wed_buf structure to store both virtual and physical
addresses allocated in mtk_wed_tx_buffer_alloc() routine. This is a
preliminary patch to add WED support for MT7988 SoC since it relies on a
different dma descriptor layout not storing page dma addresses.
Co-developed-by: Sujuan Chen <sujuan.chen@mediatek.com>
Signed-off-by: Sujuan Chen <sujuan.chen@mediatek.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/mediatek/mtk_wed.c

@@ -300,9 +300,9 @@ mtk_wed_assign(struct mtk_wed_device *dev)
 static int
 mtk_wed_tx_buffer_alloc(struct mtk_wed_device *dev)
 {
+	struct mtk_wed_buf *page_list;
 	struct mtk_wdma_desc *desc;
 	dma_addr_t desc_phys;
-	void **page_list;
 	int token = dev->wlan.token_start;
 	int ring_size;
 	int n_pages;
@@ -343,7 +343,8 @@ mtk_wed_tx_buffer_alloc(struct mtk_wed_device *dev)
 			return -ENOMEM;
 		}
 
-		page_list[page_idx++] = page;
+		page_list[page_idx].p = page;
+		page_list[page_idx++].phy_addr = page_phys;
 		dma_sync_single_for_cpu(dev->hw->dev, page_phys, PAGE_SIZE,
 					DMA_BIDIRECTIONAL);
 
@@ -387,8 +388,8 @@ mtk_wed_tx_buffer_alloc(struct mtk_wed_device *dev)
 static void
 mtk_wed_free_tx_buffer(struct mtk_wed_device *dev)
 {
+	struct mtk_wed_buf *page_list = dev->tx_buf_ring.pages;
 	struct mtk_wdma_desc *desc = dev->tx_buf_ring.desc;
-	void **page_list = dev->tx_buf_ring.pages;
 	int page_idx;
 	int i;
 
@@ -400,13 +401,12 @@ mtk_wed_free_tx_buffer(struct mtk_wed_device *dev)
 
 	for (i = 0, page_idx = 0; i < dev->tx_buf_ring.size;
 	     i += MTK_WED_BUF_PER_PAGE) {
-		void *page = page_list[page_idx++];
-		dma_addr_t buf_addr;
+		dma_addr_t buf_addr = page_list[page_idx].phy_addr;
+		void *page = page_list[page_idx++].p;
 
 		if (!page)
 			break;
 
-		buf_addr = le32_to_cpu(desc[i].buf0);
 		dma_unmap_page(dev->hw->dev, buf_addr, PAGE_SIZE,
 			       DMA_BIDIRECTIONAL);
 		__free_page(page);

include/linux/soc/mediatek/mtk_wed.h

@@ -76,6 +76,11 @@ struct mtk_wed_wo_rx_stats {
 	__le32 rx_drop_cnt;
 };
 
+struct mtk_wed_buf {
+	void *p;
+	dma_addr_t phy_addr;
+};
+
 struct mtk_wed_device {
 #ifdef CONFIG_NET_MEDIATEK_SOC_WED
 	const struct mtk_wed_ops *ops;
@@ -97,7 +102,7 @@ struct mtk_wed_device {
 
 	struct {
 		int size;
-		void **pages;
+		struct mtk_wed_buf *pages;
 		struct mtk_wdma_desc *desc;
 		dma_addr_t desc_phys;
 	} tx_buf_ring;