From patchwork Tue Dec 7 11:00:52 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomoya X-Patchwork-Id: 74508 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id EC1F8B70E0 for ; Tue, 7 Dec 2010 21:58:33 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755287Ab0LGK6H (ORCPT ); Tue, 7 Dec 2010 05:58:07 -0500 Received: from sm-d311v.smileserver.ne.jp ([203.211.202.206]:33182 "EHLO sm-d311v.smileserver.ne.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751856Ab0LGK6F (ORCPT ); Tue, 7 Dec 2010 05:58:05 -0500 X-Virus-Status: clean(F-Secure/virusgw_smtp/403/viruscheck1-00.private.hosting-pf.net) Message-ID: <4CFE13E4.2020707@dsn.okisemi.com> Date: Tue, 07 Dec 2010 20:00:52 +0900 From: Tomoya MORINAGA User-Agent: Mozilla/5.0 (X11; U; Linux i686; ja; rv:1.9.2.12) Gecko/20101027 Thunderbird/3.1.6 MIME-Version: 1.0 To: Wolfgang Grandegger , socketcan-core@lists.berlios.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org CC: qi.wang@intel.com, yong.y.wang@intel.com, andrew.chih.howe.khor@intel.com, joel.clark@intel.com, kok.howg.ewe@intel.com, margie.foster@intel.com Subject: [PATCH net-next-2.6 v8 01/20] CAN : Add flow control processing. Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Currently, there is no flow control processing. Thus, Add flow control processing as when there is no empty of tx buffer, netif_stop_queue is called. When there is empty buffer, netif_wake_queue is called. Signed-off-by: Tomoya MORINAGA --- drivers/net/can/pch_can.c | 31 ++++++++++++------------------- 1 files changed, 12 insertions(+), 19 deletions(-) diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c index a9b6a65..f0f1404 100644 --- a/drivers/net/can/pch_can.c +++ b/drivers/net/can/pch_can.c @@ -102,6 +102,10 @@ #define PCH_FIFO_THRESH 16 +/* TxRqst2 show status of MsgObjNo.17~32 */ +#define PCH_TREQ2_TX_MASK (((1 << PCH_TX_OBJ_NUM) - 1) <<\ + (PCH_RX_OBJ_END - 16)) + enum pch_ifreg { PCH_RX_IFREG, PCH_TX_IFREG, @@ -871,6 +875,8 @@ MSG_OBJ: dlc = 8; stats->tx_bytes += dlc; stats->tx_packets++; + if (int_stat == PCH_TX_OBJ_END) + netif_wake_queue(ndev); } int_stat = pch_can_int_pending(priv); @@ -1009,18 +1015,6 @@ static int pch_close(struct net_device *ndev) return 0; } -static int pch_get_msg_obj_sts(struct net_device *ndev, u32 obj_id) -{ - u32 buffer_status = 0; - struct pch_can_priv *priv = netdev_priv(ndev); - - /* Getting the message object status. */ - buffer_status = (u32) pch_can_get_buffer_status(priv); - - return buffer_status & obj_id; -} - - static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev) { int i, j; @@ -1031,17 +1025,16 @@ static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev) if (can_dropped_invalid_skb(ndev, skb)) return NETDEV_TX_OK; - if (priv->tx_obj == PCH_TX_OBJ_END) { /* Point tail Obj */ - while (pch_get_msg_obj_sts(ndev, (((1 << PCH_TX_OBJ_NUM)-1) << - PCH_RX_OBJ_NUM))) - udelay(500); + if (priv->tx_obj == PCH_TX_OBJ_END) { + if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK) + netif_stop_queue(ndev); - priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj ID */ - tx_buffer_avail = priv->tx_obj; /* Point Tail of Tx Obj */ + tx_buffer_avail = priv->tx_obj; + priv->tx_obj = PCH_TX_OBJ_START; } else { tx_buffer_avail = priv->tx_obj; + priv->tx_obj++; } - priv->tx_obj++; /* Reading the Msg Obj from the Msg RAM to the Interface register. */ iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);