From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E0352C73C46 for ; Tue, 9 Jul 2019 16:16:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B982E216E3 for ; Tue, 9 Jul 2019 16:16:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Ds586ejC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726569AbfGIQP7 (ORCPT ); Tue, 9 Jul 2019 12:15:59 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:47048 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725816AbfGIQP7 (ORCPT ); Tue, 9 Jul 2019 12:15:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=dCpzFzu5/U/he9Oo9VsjZUs68uCHS4wh8DDRIspguLY=; b=Ds586ejCEExvMxDQM6zwFPeBH kaA+bMZBmskIlrdYh8RE6ZVHf9Lh+O+gJE5BmWCqK3tbZhqGYVk4AwTGtSKs6o/CWdpUMUJuezJ1T tXrlXR1ng40iAM4lhSAwrOeuZ7kzTyfZ5rShXjpLIXSUB+bSSHGCMl6FI8TSwOyXEXofGEpSwiCtw vjsLaLVrOmIuzT46BuLplm5VZS/G/cxkCs2bi/YvnfCHAjxY25sRekw1BFgbaD+3lJgxHLZiR9oNH cZXpXN0SB7wlerrq2i37lxXPnzF+GL38QPexntwuX8wQ0GmeLCvsIlgHr9KT9FobLmrrgnBSg5f2s Vpp/7zbyg==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1hksmU-0003ek-Hu; Tue, 09 Jul 2019 16:15:50 +0000 Date: Tue, 9 Jul 2019 09:15:50 -0700 From: Christoph Hellwig To: Jian-Hong Pan Cc: Yan-Hsuan Chuang , Kalle Valo , "David S . Miller" , Larry Finger , David Laight , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux@endlessm.com, Daniel Drake Subject: Re: [PATCH v2 2/2] rtw88: pci: Use DMA sync instead of remapping in RX ISR Message-ID: <20190709161550.GA8703@infradead.org> References: <20190708063252.4756-1-jian-hong@endlessm.com> <20190709102059.7036-2-jian-hong@endlessm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190709102059.7036-2-jian-hong@endlessm.com> User-Agent: Mutt/1.11.4 (2019-03-13) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org 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 > --- > 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.