From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Tom Sylla" Subject: Fwd: confusion about libata.force=80c Date: Tue, 20 May 2008 05:22:10 -0400 Message-ID: <57947bf80805200222j19efa2d2n7ff89fe026745ba1@mail.gmail.com> References: <57947bf80805141120v615ef957g323114637d171f0a@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from fg-out-1718.google.com ([72.14.220.155]:2777 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758401AbYETJWM (ORCPT ); Tue, 20 May 2008 05:22:12 -0400 Received: by fg-out-1718.google.com with SMTP id 19so1936446fgg.17 for ; Tue, 20 May 2008 02:22:10 -0700 (PDT) In-Reply-To: <57947bf80805141120v615ef957g323114637d171f0a@mail.gmail.com> Content-Disposition: inline Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: linux-ide@vger.kernel.org Anyone have a comment? All I am asking for now is if this *should* work or not. Is force=80c supposed to do what I want? ---------- Forwarded message ---------- From: Tom Sylla Date: Wed, May 14, 2008 at 2:20 PM Subject: confusion about libata.force=80c To: linux-ide@vger.kernel.org I have a platform with a single CompactFlash socket connected to a Broadcom HT1000's PATA port. With libata's pata_serverworks, it ends up using drive-side 80-conductor cable detection (Broadcom provides no cable bits for the BIOS to report what is attached). The CompactFlashes I am using mis-report the cable type, and pata_serverworks limits to UDMA2. I tried to use the recent addition of libata.force, but it does not seem to work like I would expect it to. An excerpt from dmesg: scsi4 : pata_serverworks scsi5 : pata_serverworks ata5: PATA max UDMA/66 cmd 0x1f0 ctl 0x3f6 bmdma 0xffa0 irq 14 ata6: PATA max UDMA/66 cmd 0x170 ctl 0x376 bmdma 0xffa8 irq 15 ata5: FORCE: cable set to 80c ata5.00: ATA-4: CF CARD, 20080308, max UDMA/66 ata5.00: 15662304 sectors, multi 0: LBA ata5.00: limited to UDMA/33 due to 40-wire cable ata5.00: configured for UDMA/33 The force parameter is certainly getting accepted, but then 3 lines later, it believes it has a 40 conductor cable. I have attached the full dmesg. This is vanilla 2.6.25.3 with "options libata force=80c" added in the initrd. Yes, I know I should just get a more well-behaved device, but both of the high-speed (UDMA) CFs I am using mis-report the cable detection. I would bet many other high-speed CFs do the same. I have already contacted the CF manufacturer to look into it. For now, though, I'd like to run UDMA4, and the force parameter seems like it would do what I want. Is force=80c what I want? Should it work? Thanks