[PATCH v3] mt76: mt7915: wed: find rx token by physical address

[Shengyu Qu]

The token id in RxDMAD may be incorrect when it is not the last frame
due to WED HW bug. Lookup correct token id by physical address in sdp0.

Downstream patch link: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/737340322ab22b138fd200e020d61ffdbe3e36a9/autobuild/autobuild_5.4_mac80211_release/mt7988_wifi7_mac80211_mlo/package/kernel/mt76/patches/0062-mtk-wifi-mt76-mt7915-wed-find-rx-token-by-physical-a.patch

Signed-off-by: Peter Chiu <chui-hao.chiu at mediatek.com>
Signed-off-by: Shengyu Qu <wiagn233 at outlook.com>
---
Changes since v1:
 - Reordered code sequence to reversed Xmas tree order
 - Renamed some variables
Changes since v2:
 - Assigning true to variable "found" instead of 1
---
 drivers/net/wireless/mediatek/mt76/dma.c | 26 +++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
index 844af16ee5513..d5649c52c669a 100644
--- a/drivers/net/wireless/mediatek/mt76/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/dma.c
@@ -445,8 +445,32 @@ mt76_dma_get_buf(struct mt76_dev *dev, struct mt76_queue *q, int idx,
 
 	if (mt76_queue_is_wed_rx(q)) {
 		u32 token = FIELD_GET(MT_DMA_CTL_TOKEN, buf1);
-		struct mt76_txwi_cache *t = mt76_rx_token_release(dev, token);
+		struct mt76_txwi_cache *t;
+		bool found = false;
+		u32 id;
+
+		if (*more) {
+			spin_lock_bh(&dev->rx_token_lock);
+
+			idr_for_each_entry(&dev->rx_token, t, id) {
+				if (t->dma_addr == le32_to_cpu(desc->buf0)) {
+					token = id;
+					found = true;
+
+					/* Write correct id back to DMA*/
+					u32p_replace_bits(&buf1, id,
+							  MT_DMA_CTL_TOKEN);
+					WRITE_ONCE(desc->buf1, cpu_to_le32(buf1));
+					break;
+				}
+			}
+
+			spin_unlock_bh(&dev->rx_token_lock);
+			if (!found)
+				return NULL;
+		}
 
+		t = mt76_rx_token_release(dev, token);
 		if (!t)
 			return NULL;
 
-- 
2.49.0