From mboxrd@z Thu Jan 1 00:00:00 1970 From: Giuseppe CAVALLARO Subject: Re: [PATCH 2/2 net-next] net: stmmac: Improve documentation on AVB parameters Date: Fri, 9 Jun 2017 09:10:33 +0200 Message-ID: <188848c4-7159-55b2-07b2-0f8c1391a484@st.com> References: <014297b3b5a1654eda19f099082d04b79a98b16a.1496944749.git.jpinto@synopsys.com> <95bf7beef1abfb3c140ef56a8f59374bf6513496.1496944749.git.jpinto@synopsys.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Cc: , , David Miller To: Joao Pinto , Return-path: Received: from mx08-00178001.pphosted.com ([91.207.212.93]:43076 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751522AbdFIHKl (ORCPT ); Fri, 9 Jun 2017 03:10:41 -0400 In-Reply-To: <95bf7beef1abfb3c140ef56a8f59374bf6513496.1496944749.git.jpinto@synopsys.com> Sender: netdev-owner@vger.kernel.org List-ID: Hi Joao On 6/8/2017 8:02 PM, Joao Pinto wrote: > This patch fixes the description of the DT AVB parameters and gives > an accurate example. It was also included the base values that were > used to get the example' CBS paremeter values. > > Signed-off-by: Joao Pinto > --- > Documentation/devicetree/bindings/net/stmmac.txt | 24 ++++++++++++++++-------- > 1 file changed, 16 insertions(+), 8 deletions(-) > > diff --git a/Documentation/devicetree/bindings/net/stmmac.txt b/Documentation/devicetree/bindings/net/stmmac.txt > index c3a7be6..707426d 100644 > --- a/Documentation/devicetree/bindings/net/stmmac.txt > +++ b/Documentation/devicetree/bindings/net/stmmac.txt > @@ -109,10 +109,10 @@ Optional properties: > [Attention] Queue 0 is reserved for legacy traffic > and so no AVB is available in this queue. > - Configure Credit Base Shaper (if AVB Mode selected): > - - snps,send_slope: enable Low Power Interface > - - snps,idle_slope: unlock on WoL > - - snps,high_credit: max write outstanding req. limit > - - snps,low_credit: max read outstanding req. limit > + - snps,send_slope: Send Slope Credit value > + - snps,idle_slope: Idle Slope Credit value > + - snps,high_credit: High Credit value > + - snps,low_credit: Low Credit value > - snps,priority: TX queue priority (Range: 0x0 to 0xF) > Examples: > > @@ -143,10 +143,18 @@ Examples: > > queue1 { > snps,avb-algorithm; > - snps,send_slope = <0x1000>; > - snps,idle_slope = <0x1000>; > - snps,high_credit = <0x3E800>; > - snps,low_credit = <0xFFC18000>; > + /* > + * Example AVB parameters based on: > + * Allocated Bandwidth: 40% > + * Maximum Frame size: 1000 bytes > + * Maximum Interference size: 1500 bytes > + * Port Transmit Rate: 8 > + * Scaling Factor: 1024 > + */ > + snps,idle_slope = <0xCCC>; > + snps,send_slope = <0x1333>; > + snps,high_credit = <0x4B0000>; Thanks for having taken care about this changes, please, as required, add a cover-letter and give more information about these values that can be tuned by user and, for example, the snps,high_credit could be as default = 0xbe4000 that is a reasonable value because comes from 1522 * 8 * 1024 and LOW credit is the two complement. ^^^^^ frame size ---> maximum is 16 Regards Peppe > + snps,low_credit = <0xFFB50000>; > snps,priority = <0x1>; > }; > };