From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754890Ab1DWOkr (ORCPT ); Sat, 23 Apr 2011 10:40:47 -0400 Received: from mail-qy0-f174.google.com ([209.85.216.174]:38497 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754695Ab1DWOkp (ORCPT ); Sat, 23 Apr 2011 10:40:45 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=I2kQo7rcWQTwy5NQImB4vllAO8LfWDgVjVGCUyVjBmR0g6bBiA5xpLMrzyLGcdGZG6 zZiYbL5gGTekGUxsU/anln16/d85bvGHfpJoz1ui0aXzIeiEx7hlFe3P/BTScAOh8TY6 Bv06UNzxHrZpSS4Cju2MaKXtXxFpUQN/pV6H0= MIME-Version: 1.0 In-Reply-To: <1303541890-14528-1-git-send-email-jipeng2005@gmail.com> References: <1303541890-14528-1-git-send-email-jipeng2005@gmail.com> Date: Sat, 23 Apr 2011 16:40:44 +0200 Message-ID: Subject: Re: [PATCH 1/1] libata: ahci_start_engine compliant to AHCI spec From: Tejun Heo To: Jian Peng Cc: Jeff Garzik , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Apr 23, 2011 at 8:58 AM, Jian Peng wrote: > At the end of section 10.1 of AHCI spec (rev 1.3), it states > > Software shall not set PxCMD.ST to 1 until it is determined that > a functoinal device is present on the port as determined by > PxTFD.STS.BSY=0, PxTFD.STS.DRQ=0 and PxSSTS.DET=3h > > Even though most AHCI host controller works without this check, > specific controller will fail under this condition. > > Signed-off-by: Jian Peng Acked-by: Tejun Heo Thanks. -- tejun