From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brad Campbell Subject: [PATCH] libata ATA vs SATA detection and workaround. Date: Mon, 30 Aug 2004 18:42:36 +0400 Sender: linux-ide-owner@vger.kernel.org Message-ID: <41333CDC.5040106@wasp.net.au> References: <41320DAF.2060306@wasp.net.au> <41321288.4090403@pobox.com> <413216CC.5080100@wasp.net.au> <4132198B.8000504@pobox.com> <41321F7F.7050300@pobox.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="=_wasp.net.au-17753-1093876919-0001-2" Return-path: Received: from wasp.net.au ([203.190.192.17]:48835 "EHLO wasp.net.au") by vger.kernel.org with ESMTP id S268340AbUH3OmD (ORCPT ); Mon, 30 Aug 2004 10:42:03 -0400 In-Reply-To: <41321F7F.7050300@pobox.com> List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: linux-ide@vger.kernel.org, Linux Kernel This is a MIME-formatted message. If you see this text it means that your E-mail software does not support MIME-formatted messages. --=_wasp.net.au-17753-1093876919-0001-2 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Jeff Garzik wrote: > Jeff Garzik wrote: > >> me either, unless I can figure out a way to detect that a disk is PATA >> not SATA. Nothing is obvious from the specs on www.t13.org, but who >> knows. > > > According to the Serial ATA docs, IDENTIFY DEVICE word 93 will be zero > if it's Serial ATA. Who knows if that's true, given the wierd wild > world of ATA devices. > I'm assuming here that if the driver uses sata_phy_reset in libata-core then it's actually a SATA controller. Patch attached, tested and verified. SATA drives (of which I only have one brand) report IDENTIFY DEVICE word 93 as zero, ATA devices behind the bridge (Of which I only have one brand) report at a minimum bit 13 to report an 80 conductor cable. Like I said before, my assumptions are A) IDENTIFY DEVICE and the associated Word 93 register have been *Mandatory* at least since ATA-5 B) ATA-5 maxed out at < udma/100 and did not contain lba48 C) The SATA->PATA bridge looks like an 80 conductor cable and thus on any drive that supports lba48 will always present a non-zero value in IDENTIFY DEVICE Word 93. It works here anyway. Patch against vanilla 2.6.9-rc1 attached (including your ata.h patch) Thanks again for all the help. I'll see if I can get some other older ATA drives to test with (I might have to gut all the machines in the office for the weekend) Regards, Brad --=_wasp.net.au-17753-1093876919-0001-2 Content-Type: text/plain; name=diff; charset=iso-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="diff" diff -ur orig/linux-2.6.0/drivers/scsi/libata-core.c linux-2.6.9-rc1/drivers/scsi/libata-core.c --- orig/linux-2.6.0/drivers/scsi/libata-core.c 2004-08-30 18:31:31.000000000 +0400 +++ linux-2.6.9-rc1/drivers/scsi/libata-core.c 2004-08-30 18:22:05.000000000 +0400 @@ -1152,6 +1152,16 @@ found = 1; if (ap->ops->dev_config) ap->ops->dev_config(ap, &ap->device[i]); + /* limit bridge transfers to udma5, 200 sectors */ + printk("Value is %u\n",ap->cbl==ATA_CBL_SATA); + if ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(ap->device))) { + printk(KERN_INFO "ata%u(%u): applying bridge limits\n", + ap->id, ap->device->devno); + ap->udma_mask &= ATA_UDMA5; + ap->host->max_sectors = ATA_MAX_SECTORS; + ap->host->hostt->max_sectors = ATA_MAX_SECTORS; + ap->device->flags |= ATA_DFLAG_LOCK_SECTORS; + } } } @@ -1226,7 +1236,7 @@ ata_port_disable(ap); return; } - + ap->cbl = ATA_CBL_SATA; ata_bus_reset(ap); } diff -ur orig/linux-2.6.0/include/linux/ata.h linux-2.6.9-rc1/include/linux/ata.h --- orig/linux-2.6.0/include/linux/ata.h 2004-08-30 18:31:32.000000000 +0400 +++ linux-2.6.9-rc1/include/linux/ata.h 2004-08-30 17:56:53.000000000 +0400 @@ -218,6 +218,7 @@ }; #define ata_id_is_ata(dev) (((dev)->id[0] & (1 << 15)) == 0) +#define ata_id_is_sata(dev) ((dev)->id[93] == 0) #define ata_id_rahead_enabled(dev) ((dev)->id[85] & (1 << 6)) #define ata_id_wcache_enabled(dev) ((dev)->id[85] & (1 << 5)) #define ata_id_has_flush(dev) ((dev)->id[83] & (1 << 12)) --=_wasp.net.au-17753-1093876919-0001-2--