RE: [PATCH v1] mt76: mt7915: wed: find rx token by physical address

[Ping-Ke Shih]

Shengyu Qu <wiagn233@xxxxxxxxxxx> wrote:
> 
> Hi Shih,
> 
> Can you also give this patch a review? Seems I also need to convert to
> reverse Xmas tree order for this patch, will do it in next version.

Yes. Please do it.

> 
> Best regards,
> Shengyu
> 
> 在 2025/2/22 19:38, Shengyu Qu 写道:
> > 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/+/737340322ab22b138fd200e02
> 0d61ffdbe3e36a9/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@xxxxxxxxxxxx>
> > Signed-off-by: Shengyu Qu <wiagn233@xxxxxxxxxxx>
> > ---
> >   drivers/net/wireless/mediatek/mt76/dma.c | 25 +++++++++++++++++++++++-
> >   1 file changed, 24 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
> > index 844af16ee551..5bf63014263c 100644
> > --- a/drivers/net/wireless/mediatek/mt76/dma.c
> > +++ b/drivers/net/wireless/mediatek/mt76/dma.c
> > @@ -444,9 +444,32 @@ mt76_dma_get_buf(struct mt76_dev *dev, struct mt76_queue *q, int idx,
> >   	mt76_dma_should_drop_buf(drop, ctrl, buf1, desc_info);
> >
> >   	if (mt76_queue_is_wed_rx(q)) {
> > +		u32 id, find = 0;
> >   		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;
> > +
> > +		if (*more) {

Because of scope, should define 'find' (or 'found'?) as bool here.

> > +			spin_lock_bh(&dev->rx_token_lock);
> > +
> > +			idr_for_each_entry(&dev->rx_token, t, id) {

idr_find() can only get a pointer associated with the ID. Not sure if it can
have a reverse way -- get ID from pointer. With sequential search in data path,
cost is higher.

Maybe you can consider to build association between argument 'idx' and
pointer/token by another patch.

But logic is okay to me.

> > +				if (t->dma_addr == le32_to_cpu(desc->buf0)) {
> > +					find = 1;
> > +					token = id;
> > +
> > +					/* 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 (!find)
> > +				return NULL;
> > +		}
> >
> > +		t = mt76_rx_token_release(dev, token);
> >   		if (!t)
> >   			return NULL;
> >