From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 2/5] sil24: add sil24_restart_controller Date: Wed, 16 Nov 2005 07:20:50 -0500 Message-ID: <437B2422.6040107@pobox.com> References: <20051116080244.GB22807@htj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail.dvmed.net ([216.237.124.58]:29619 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S1030301AbVKPMUx (ORCPT ); Wed, 16 Nov 2005 07:20:53 -0500 In-Reply-To: <20051116080244.GB22807@htj.dyndns.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: linux-ide@vger.kernel.org Tejun Heo wrote: > When an error condition is raised by device via D2H FIS or SDB. sil24 > controller should be restarted by setting PORT_CS_INIT and waiting > until PORT_CS_RDY is asserted instead of resetting the controller. > This patch implements sil24_restart_controller for those cases. This > patch also makes sure that PORT_CS_RDY is asserted on > sil24_reset_controller completion. > > Signed-off-by: Tejun Heo > > -- > > Jeff, the patch named "sil24: add constants" is 1/5 and should be > applied first. Sorry. > > Index: work/drivers/scsi/sata_sil24.c > =================================================================== > --- work.orig/drivers/scsi/sata_sil24.c 2005-11-16 16:54:10.000000000 +0900 > +++ work/drivers/scsi/sata_sil24.c 2005-11-16 16:58:01.000000000 +0900 > @@ -486,6 +486,31 @@ static void sil24_irq_clear(struct ata_p > /* unused */ > } > > +static int __sil24_restart_controller(void __iomem *port) > +{ > + u32 tmp; > + int cnt; > + > + writel(PORT_CS_INIT, port + PORT_CTRL_STAT); > + > + /* Max ~100ms */ > + for (cnt = 0; cnt < 1000; cnt++) { > + tmp = readl(port + PORT_CTRL_STAT); > + if (tmp & PORT_CS_RDY) > + return 0; > + udelay(100); > + } > + > + return -1; > +} NAK, this potentially soaks up an entire timer tick (~100ms). It's probably better to schedule_work(), and poll using msleep(). Or you could cut the worst case down to 10ms. FWIW, I have no idea what the max is, I don't see it in the docs :( Jeff