Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753505AbdDKMlh (ORCPT ); Tue, 11 Apr 2017 08:41:37 -0400 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:44630 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752497AbdDKMlf (ORCPT ); Tue, 11 Apr 2017 08:41:35 -0400 Subject: Re: [PATCH net-next] net: stmmac: set total length of the packet to be transmitted in TDES3 To: Niklas Cassel , , References: <20170410183329.28847-1-niklass@axis.com> CC: , , Niklas Cassel From: Giuseppe CAVALLARO Message-ID: Date: Tue, 11 Apr 2017 14:41:22 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <20170410183329.28847-1-niklass@axis.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.48] X-ClientProxiedBy: SFHDAG6NODE1.st.com (10.75.127.16) To GPXDAG4NODE4.st.com (10.75.127.74) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-04-11_10:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8075 Lines: 178 On 4/10/2017 8:33 PM, Niklas Cassel wrote: > From: Niklas Cassel > > Field FL/TPL in register TDES3 is not correctly set on GMAC4. > TX appears to be functional on GMAC 4.10a even if this field is not set, > however, to avoid relying on undefined behavior, set the length in TDES3. > > The field has a different meaning depending on if the TSE bit in TDES3 > is set or not (TSO). However, regardless of the TSE bit, the field is > not optional. The field is already set correctly when the TSE bit is set. > > Since there is no limit for the number of descriptors that can be > used for a single packet, the field should be set to the sum of > the buffers contained in: > [ ... ... > ], which should be equal to skb->len. > > Signed-off-by: Niklas Cassel Acked-by: Giuseppe Cavallaro > --- > drivers/net/ethernet/stmicro/stmmac/chain_mode.c | 6 +++--- > drivers/net/ethernet/stmicro/stmmac/common.h | 2 +- > drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c | 3 ++- > drivers/net/ethernet/stmicro/stmmac/enh_desc.c | 2 +- > drivers/net/ethernet/stmicro/stmmac/norm_desc.c | 2 +- > drivers/net/ethernet/stmicro/stmmac/ring_mode.c | 9 ++++++--- > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 +++-- > 7 files changed, 17 insertions(+), 12 deletions(-) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c > index 37881f81319e..e93c40b4631e 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c > +++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c > @@ -52,7 +52,7 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) > tx_q->tx_skbuff_dma[entry].len = bmax; > /* do not close the descriptor and do not set own bit */ > priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum, STMMAC_CHAIN_MODE, > - 0, false); > + 0, false, skb->len); > > while (len != 0) { > tx_q->tx_skbuff[entry] = NULL; > @@ -70,7 +70,7 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) > tx_q->tx_skbuff_dma[entry].len = bmax; > priv->hw->desc->prepare_tx_desc(desc, 0, bmax, csum, > STMMAC_CHAIN_MODE, 1, > - false); > + false, skb->len); > len -= bmax; > i++; > } else { > @@ -85,7 +85,7 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) > /* last descriptor can be set now */ > priv->hw->desc->prepare_tx_desc(desc, 0, len, csum, > STMMAC_CHAIN_MODE, 1, > - true); > + true, skb->len); > len = 0; > } > } > diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h > index 90d28bcad880..b7ce3fbb5375 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/common.h > +++ b/drivers/net/ethernet/stmicro/stmmac/common.h > @@ -373,7 +373,7 @@ struct stmmac_desc_ops { > /* Invoked by the xmit function to prepare the tx descriptor */ > void (*prepare_tx_desc) (struct dma_desc *p, int is_fs, int len, > bool csum_flag, int mode, bool tx_own, > - bool ls); > + bool ls, unsigned int tot_pkt_len); > void (*prepare_tso_tx_desc)(struct dma_desc *p, int is_fs, int len1, > int len2, bool tx_own, bool ls, > unsigned int tcphdrlen, > diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c > index 843ec69222ea..aa6476439aee 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c > +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c > @@ -304,12 +304,13 @@ static void dwmac4_rd_init_tx_desc(struct dma_desc *p, int mode, int end) > > static void dwmac4_rd_prepare_tx_desc(struct dma_desc *p, int is_fs, int len, > bool csum_flag, int mode, bool tx_own, > - bool ls) > + bool ls, unsigned int tot_pkt_len) > { > unsigned int tdes3 = le32_to_cpu(p->des3); > > p->des2 |= cpu_to_le32(len & TDES2_BUFFER1_SIZE_MASK); > > + tdes3 |= tot_pkt_len & TDES3_PACKET_SIZE_MASK; > if (is_fs) > tdes3 |= TDES3_FIRST_DESCRIPTOR; > else > diff --git a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c > index 323b59ec74a3..7546b3664113 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/enh_desc.c > +++ b/drivers/net/ethernet/stmicro/stmmac/enh_desc.c > @@ -315,7 +315,7 @@ static void enh_desc_release_tx_desc(struct dma_desc *p, int mode) > > static void enh_desc_prepare_tx_desc(struct dma_desc *p, int is_fs, int len, > bool csum_flag, int mode, bool tx_own, > - bool ls) > + bool ls, unsigned int tot_pkt_len) > { > unsigned int tdes0 = le32_to_cpu(p->des0); > > diff --git a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c > index efb818ebd55e..f817f8f36569 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c > +++ b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c > @@ -191,7 +191,7 @@ static void ndesc_release_tx_desc(struct dma_desc *p, int mode) > > static void ndesc_prepare_tx_desc(struct dma_desc *p, int is_fs, int len, > bool csum_flag, int mode, bool tx_own, > - bool ls) > + bool ls, unsigned int tot_pkt_len) > { > unsigned int tdes1 = le32_to_cpu(p->des1); > > diff --git a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c > index 31213e64513d..28e4b5d50ce6 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c > +++ b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c > @@ -59,7 +59,8 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) > > desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB); > priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum, > - STMMAC_RING_MODE, 0, false); > + STMMAC_RING_MODE, 0, > + false, skb->len); > tx_q->tx_skbuff[entry] = NULL; > entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE); > > @@ -79,7 +80,8 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) > > desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB); > priv->hw->desc->prepare_tx_desc(desc, 0, len, csum, > - STMMAC_RING_MODE, 1, true); > + STMMAC_RING_MODE, 1, > + true, skb->len); > } else { > des2 = dma_map_single(priv->device, skb->data, > nopaged_len, DMA_TO_DEVICE); > @@ -91,7 +93,8 @@ static int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) > tx_q->tx_skbuff_dma[entry].is_jumbo = true; > desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB); > priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum, > - STMMAC_RING_MODE, 0, true); > + STMMAC_RING_MODE, 0, > + true, skb->len); > } > > tx_q->cur_tx = entry; > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > index a89f76b27ea2..5c1ebc70bebd 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > @@ -3033,7 +3033,8 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) > > /* Prepare the descriptor and set the own bit too */ > priv->hw->desc->prepare_tx_desc(desc, 0, len, csum_insertion, > - priv->mode, 1, last_segment); > + priv->mode, 1, last_segment, > + skb->len); > } > > entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE); > @@ -3116,7 +3117,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) > /* Prepare the first descriptor setting the OWN bit too */ > priv->hw->desc->prepare_tx_desc(first, 1, nopaged_len, > csum_insertion, priv->mode, 1, > - last_segment); > + last_segment, skb->len); > > /* The own bit must be the latest setting done when prepare the > * descriptor and then barrier is needed to make sure that