[PATCH net v6 4/4] net: ethernet: mtk_wed: setup WDMA_RING_TX(0) for non-DBDC MT7986

[Zhi-Jun You]

WDMA_RING_TX(0) is required to set MTK_WED_WDMA_RING_TX for WED RX
but on a non-DBDC MT7986 it is never setup because idx is 1.

Setting MTK_WED_WDMA_RING_TX with WDMA_RING_TX(1) is not feasible because
WED still tries to send through WDMA_RING_TX(0). This is verified with
register dump.

Fix this by calling mtk_wed_wdma_tx_ring_setup if wed is v2 and
rx_ring[0] is not allocated and reset tx_wdma[0] if it's already
allocated also add error messages and bail when mtk_wed_start fails.

Fixes: 4c5de09eb0d0 ("net: ethernet: mtk_wed: add configure wed wo support")
Signed-off-by: Zhi-Jun You <hujy652 at gmail.com>
---
 drivers/net/ethernet/mediatek/mtk_wed.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_wed.c b/drivers/net/ethernet/mediatek/mtk_wed.c
index 3044a7a8ea03..f40ac5794341 100644
--- a/drivers/net/ethernet/mediatek/mtk_wed.c
+++ b/drivers/net/ethernet/mediatek/mtk_wed.c
@@ -2345,7 +2345,20 @@ mtk_wed_start(struct mtk_wed_device *dev, u32 irq_mask)
 
 	for (i = 0; i < ARRAY_SIZE(dev->rx_wdma); i++)
 		if (!dev->rx_wdma[i].desc)
-			mtk_wed_wdma_rx_ring_setup(dev, i, 16, false);
+			if (mtk_wed_wdma_rx_ring_setup(dev, i, 16, false)) {
+				dev_err(dev->hw->dev, "wdma rx ring %d setup failed\n", i);
+				return;
+			}
+
+	/*
+	 * non-DBDC MT7986 allocates only rx_ring[1] and tx_wdma[1] during setup
+	 * but tx_wdma[0] is also needed for WED to function.
+	 */
+	if (mtk_wed_is_v2(dev->hw) && !dev->rx_ring[0].desc)
+		if (mtk_wed_wdma_tx_ring_setup(dev, 0, MTK_WED_WDMA_RING_SIZE, !!dev->tx_wdma[0].desc)) {
+			dev_err(dev->hw->dev, "wdma tx ring 0 setup failed\n");
+			return;
+		}
 
 	if (dev->wlan.hw_rro) {
 		for (i = 0; i < MTK_WED_RX_PAGE_QUEUES; i++) {

-- 
2.55.0