From: Felix Fietkau <nbd@nbd.name>
Date: Tue, 24 Mar 2020 10:57:43 +0000 (+0100)
Subject: mt76: add memory barrier to DMA queue kick
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2d68104742a90f035ee8ceaddf322f6e2da32f70;p=linux.git

mt76: add memory barrier to DMA queue kick

Ensure that descriptor memory has been fully written before letting the
hardware read it

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
index 7545b552db252..24ff21eedbd0f 100644
--- a/drivers/net/wireless/mediatek/mt76/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/dma.c
@@ -143,6 +143,7 @@ mt76_dma_sync_idx(struct mt76_dev *dev, struct mt76_queue *q)
 static void
 mt76_dma_kick_queue(struct mt76_dev *dev, struct mt76_queue *q)
 {
+	wmb();
 	writel(q->head, &q->regs->cpu_idx);
 }