From 75d4bf1f5590183a60557dac4daa4749f4dac6ef Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Thu, 27 Aug 2020 07:58:32 +0200 Subject: [PATCH] mt76: dma: cache dma map address/len in struct mt76_queue_entry Accessing them from uncached memory can be expensive, so it's cheaper to cache them Signed-off-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/dma.c | 43 ++++++++++++++----------------- drivers/net/wireless/mediatek/mt76/mt76.h | 2 ++ 2 files changed, 22 insertions(+), 23 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c index 7f669a2..38cc40c 100644 --- a/drivers/net/wireless/mediatek/mt76/dma.c +++ b/drivers/net/wireless/mediatek/mt76/dma.c @@ -49,6 +49,7 @@ mt76_dma_add_buf(struct mt76_dev *dev, struct mt76_queue *q, struct mt76_queue_buf *buf, int nbufs, u32 info, struct sk_buff *skb, void *txwi) { + struct mt76_queue_entry *entry; struct mt76_desc *desc; u32 ctrl; int i, idx = -1; @@ -61,16 +62,27 @@ mt76_dma_add_buf(struct mt76_dev *dev, struct mt76_queue *q, for (i = 0; i < nbufs; i += 2, buf += 2) { u32 buf0 = buf[0].addr, buf1 = 0; + idx = q->head; + q->head = (q->head + 1) % q->ndesc; + + desc = &q->desc[idx]; + entry = &q->entry[idx]; + if (buf[0].skip_unmap) - q->entry[q->head].skip_buf0 = true; - q->entry[q->head].skip_buf1 = i == nbufs - 1; + entry->skip_buf0 = true; + entry->skip_buf1 = i == nbufs - 1; + + entry->dma_addr[0] = buf[0].addr; + entry->dma_len[0] = buf[0].len; ctrl = FIELD_PREP(MT_DMA_CTL_SD_LEN0, buf[0].len); if (i < nbufs - 1) { + entry->dma_addr[1] = buf[1].addr; + entry->dma_len[1] = buf[1].len; buf1 = buf[1].addr; ctrl |= FIELD_PREP(MT_DMA_CTL_SD_LEN1, buf[1].len); if (buf[1].skip_unmap) - q->entry[q->head].skip_buf1 = true; + entry->skip_buf1 = true; } if (i == nbufs - 1) @@ -78,11 +90,6 @@ mt76_dma_add_buf(struct mt76_dev *dev, struct mt76_queue *q, else if (i == nbufs - 2) ctrl |= MT_DMA_CTL_LAST_SEC1; - idx = q->head; - q->head = (q->head + 1) % q->ndesc; - - desc = &q->desc[idx]; - WRITE_ONCE(desc->buf0, cpu_to_le32(buf0)); WRITE_ONCE(desc->buf1, cpu_to_le32(buf1)); WRITE_ONCE(desc->info, cpu_to_le32(info)); @@ -102,24 +109,14 @@ mt76_dma_tx_cleanup_idx(struct mt76_dev *dev, struct mt76_queue *q, int idx, struct mt76_queue_entry *prev_e) { struct mt76_queue_entry *e = &q->entry[idx]; - __le32 __ctrl = READ_ONCE(q->desc[idx].ctrl); - u32 ctrl = le32_to_cpu(__ctrl); - - if (!e->skip_buf0) { - __le32 addr = READ_ONCE(q->desc[idx].buf0); - u32 len = FIELD_GET(MT_DMA_CTL_SD_LEN0, ctrl); - dma_unmap_single(dev->dev, le32_to_cpu(addr), len, + if (!e->skip_buf0) + dma_unmap_single(dev->dev, e->dma_addr[0], e->dma_len[0], DMA_TO_DEVICE); - } - - if (!e->skip_buf1) { - __le32 addr = READ_ONCE(q->desc[idx].buf1); - u32 len = FIELD_GET(MT_DMA_CTL_SD_LEN1, ctrl); - dma_unmap_single(dev->dev, le32_to_cpu(addr), len, + if (!e->skip_buf1) + dma_unmap_single(dev->dev, e->dma_addr[1], e->dma_len[1], DMA_TO_DEVICE); - } if (e->txwi == DMA_DUMMY_DATA) e->txwi = NULL; @@ -207,7 +204,7 @@ mt76_dma_get_buf(struct mt76_dev *dev, struct mt76_queue *q, int idx, void *buf = e->buf; int buf_len = SKB_WITH_OVERHEAD(q->buf_size); - buf_addr = le32_to_cpu(READ_ONCE(desc->buf0)); + buf_addr = e->dma_addr[0]; if (len) { u32 ctl = le32_to_cpu(READ_ONCE(desc->ctrl)); *len = FIELD_GET(MT_DMA_CTL_SD_LEN0, ctl); diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h index 2d44fe5..9dbb7dd 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76.h +++ b/drivers/net/wireless/mediatek/mt76/mt76.h @@ -102,6 +102,8 @@ struct mt76_queue_entry { struct urb *urb; int buf_sz; }; + u32 dma_addr[2]; + u16 dma_len[2]; u16 wcid; bool skip_buf0:1; bool skip_buf1:1; -- 2.7.4