From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754195AbbLJXjq (ORCPT ); Thu, 10 Dec 2015 18:39:46 -0500 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:44011 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752210AbbLJXjp (ORCPT ); Thu, 10 Dec 2015 18:39:45 -0500 Date: Fri, 11 Dec 2015 10:39:36 +1100 (AEDT) From: Finn Thain To: Ondrej Zary cc: Michael Schmitz , linux-m68k@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 74/71] ncr5380: Enable PDMA for NCR53C400A In-Reply-To: <201512091439.07424.linux@rainbow-software.org> Message-ID: References: <20151118083455.331768508@telegraphics.com.au> <1449440489-9986-1-git-send-email-linux@rainbow-software.org> <201512091439.07424.linux@rainbow-software.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 9 Dec 2015, Ondrej Zary wrote: > On Tuesday 08 December 2015 03:05:11 Finn Thain wrote: > > > > On Sun, 6 Dec 2015, Ondrej Zary wrote: > > > > > Add I/O register mapping for NCR53C400A and enable PDMA mode to > > > improve performance and fix non-working IRQ. > > > > > > Tested with HP C2502 (and user-space enabler). > > > > > > Signed-off-by: Ondrej Zary > > > --- > > > drivers/scsi/g_NCR5380.c | 14 +++++++++++--- > > > 1 file changed, 11 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c > > > index 86740fd..099fdac 100644 > > > --- a/drivers/scsi/g_NCR5380.c > > > +++ b/drivers/scsi/g_NCR5380.c > > > @@ -324,7 +324,7 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt) > > > #endif > > > break; > > > case BOARD_NCR53C400A: > > > - flags = FLAG_NO_PSEUDO_DMA; > > > + flags = FLAG_NO_DMA_FIXUP; > > > ports = ncr_53c400a_ports; > > > break; > > > case BOARD_DTC3181E: > > > @@ -406,11 +406,18 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt) > > > * On NCR53C400 boards, NCR5380 registers are mapped 8 past > > > * the base address. > > > */ > > > - if (overrides[current_override].board == BOARD_NCR53C400) { > > > + switch (overrides[current_override].board) { > > > + case BOARD_NCR53C400: > > > instance->io_port += 8; > > > hostdata->c400_ctl_status = 0; > > > hostdata->c400_blk_cnt = 1; > > > hostdata->c400_host_buf = 4; > > > + break; > > > + case BOARD_NCR53C400A: > > > + hostdata->c400_ctl_status = 9; > > > + hostdata->c400_blk_cnt = 10; > > > + hostdata->c400_host_buf = 8; > > > + break; > > > } > > > #else > > > instance->base = overrides[current_override].NCR5380_map_name; > > > > > > For SCSI_G_NCR5380_MEM and BOARD_NCR53C400A (or BOARD_DTC3181E), you have > > not assigned c400_ctl_status, c400_blk_cnt and c400_host_buf. Perhaps we > > should throw an error, something like this? > > > > hostdata->iomem = iomem; > > - if (overrides[current_override].board == BOARD_NCR53C400) { > > + switch (overrides[current_override].board) { > > + case BOARD_NCR53C400: > > hostdata->c400_ctl_status = 0x100; > > hostdata->c400_blk_cnt = 0x101; > > hostdata->c400_host_buf = 0x104; > > + break; > > + case BOARD_NCR53C400A: > > + pr_err(DRV_MODULE_NAME ": unknown register offsets\n"); > > + goto out_unregister; > > } > > #endif > > We don't need to fail, just disable PDMA by setting: > flags = FLAG_NO_PSEUDO_DMA; > > And BTW. this: > if (overrides[current_override].board == BOARD_NCR53C400 || > overrides[current_override].board == BOARD_NCR53C400A) > NCR5380_write(hostdata->c400_ctl_status, CSR_BASE); > > should then be, solving the problem of growing if condition: > if (!(flags & FLAG_NO_PSEUDO_DMA)) > NCR5380_write(hostdata->c400_ctl_status, CSR_BASE); > We already resolved that problem. Julian Calaby and I agreed that a switch statement is better than a flag here. Moreover, if the user sets the 'ncr_53c400' or 'ncr_53c400a' module options I presume they expect corresponding device initialization. I don't think PIO means we should skip that. Passing 'ncr_53c400' or 'ncr_53c400a' options to the g_NCR5380_mmio module has to give an error if we don't have enough information about the board to allow us to do the right thing. (Passing the 'ncr_5380' module param may give the result you wanted.) BTW, I fixed up this patch when I added it to my queue. I'll send you my version to test. Thanks. --