From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH v2 net-next] net: stmmac: add drop transmit status feature Date: Wed, 12 Apr 2017 13:56:43 +0200 Message-ID: <20170412115643.GA32596@lunn.ch> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: davem@davemloft.net, netdev@vger.kernel.org To: Joao Pinto Return-path: Received: from vps0.lunn.ch ([178.209.37.122]:56391 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751106AbdDLL4u (ORCPT ); Wed, 12 Apr 2017 07:56:50 -0400 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Apr 12, 2017 at 10:26:20AM +0100, Joao Pinto wrote: > When the Drop Transmit Status bit is set, the Tx packet status > received from the MAC is dropped in the MTL. When this bit is reset, > the Tx packet status received from the MAC is forwarded to the > application. This feature will cause a performance improvement. > > Signed-off-by: Joao Pinto > --- > changes v1->v2: > - removed mask from dwmac4_enable_tx_drop() > > Documentation/devicetree/bindings/net/stmmac.txt | 1 + > drivers/net/ethernet/stmicro/stmmac/common.h | 2 ++ > drivers/net/ethernet/stmicro/stmmac/dwmac4.h | 1 + > drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c | 12 ++++++++++++ > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 +++ > drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 2 ++ > include/linux/stmmac.h | 1 + > 7 files changed, 22 insertions(+) > > diff --git a/Documentation/devicetree/bindings/net/stmmac.txt b/Documentation/devicetree/bindings/net/stmmac.txt > index f652b0c..dbcb2cc 100644 > --- a/Documentation/devicetree/bindings/net/stmmac.txt > +++ b/Documentation/devicetree/bindings/net/stmmac.txt > @@ -60,6 +60,7 @@ Optional properties: > and MAC2MAC connection. > - snps,tso: this enables the TSO feature otherwise it will be managed by > MAC HW capability register. Only for GMAC4 and newer. > +- snps,drop-tx-status: this enables drop tx status Hi Joao Was the conclusion from testing that this cannot be turned on by default? What sort of performance improvement did you get? Do you have some benchmark numbers? Andrew