On Tue, Jul 09, 2019 at 06:21:01PM +0800, Jian-Hong Pan wrote:
> Since each skb in RX ring is reused instead of new allocation, we can
> treat the DMA in a more efficient way by DMA synchronization.
>
> Signed-off-by: Jian-Hong Pan <jian-hong@xxxxxxxxxxxx>
> ---
> drivers/net/wireless/realtek/rtw88/pci.c | 35 ++++++++++++++++++++++--
> 1 file changed, 32 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/wireless/realtek/rtw88/pci.c b/drivers/net/wireless/realtek/rtw88/pci.c
> index e9fe3ad896c8..28ca76f71dfe 100644
> --- a/drivers/net/wireless/realtek/rtw88/pci.c
> +++ b/drivers/net/wireless/realtek/rtw88/pci.c
> @@ -206,6 +206,35 @@ static int rtw_pci_reset_rx_desc(struct rtw_dev *rtwdev, struct sk_buff *skb,
> return 0;
> }
>
> +static int rtw_pci_sync_rx_desc_cpu(struct rtw_dev *rtwdev, dma_addr_t dma)
> +{
> + struct device *dev = rtwdev->dev;
> + int buf_sz = RTK_PCI_RX_BUF_SIZE;
> +
> + dma_sync_single_for_cpu(dev, dma, buf_sz, PCI_DMA_FROMDEVICE);
> +
> + return 0;
> +}
No need to return a value from this helper. In fact I'm not even sure
you need the helper at all. Also please use the DMA_FROM_DEVICE
constant instead of the deprecated PCI variant.
> +static int rtw_pci_sync_rx_desc_device(struct rtw_dev *rtwdev, dma_addr_t dma,
> + struct rtw_pci_rx_ring *rx_ring,
> + u32 idx, u32 desc_sz)
> +{
> + struct device *dev = rtwdev->dev;
> + struct rtw_pci_rx_buffer_desc *buf_desc;
> + int buf_sz = RTK_PCI_RX_BUF_SIZE;
> +
> + dma_sync_single_for_device(dev, dma, buf_sz, PCI_DMA_FROMDEVICE);
> +
> + buf_desc = (struct rtw_pci_rx_buffer_desc *)(rx_ring->r.head +
> + idx * desc_sz);
> + memset(buf_desc, 0, sizeof(*buf_desc));
> + buf_desc->buf_size = cpu_to_le16(RTK_PCI_RX_BUF_SIZE);
> + buf_desc->dma = cpu_to_le32(dma);
> +
> + return 0;
> +}
Same comment on the PCI constant and the return value here.
