From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755769AbbLDJIl (ORCPT ); Fri, 4 Dec 2015 04:08:41 -0500 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:33170 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754335AbbLDJIc (ORCPT ); Fri, 4 Dec 2015 04:08:32 -0500 Date: Fri, 4 Dec 2015 20:08:21 +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: [RFC PATCH 76/71] ncr5380: Enable PDMA for DTC chips In-Reply-To: <1449183781-2163-1-git-send-email-linux@rainbow-software.org> Message-ID: References: <20151118083455.331768508@telegraphics.com.au> <1449183781-2163-1-git-send-email-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 Fri, 4 Dec 2015, Ondrej Zary wrote: > Add I/O register mapping for DTC chips and enable PDMA mode. > > These chips have 16-bit wide HOST BUFFER register (counter register at > offset 0x0d increments by 2 on each HOST BUFFER read). > > Large PIO transfers crash at least the DTCT-436P chip (all reads result > in 0xFF) so this patch actually makes it work. > > The chip also crashes when we bang the C400 host status register too > heavily after PDMA write - a small udelay is needed. > > Signed-off-by: Ondrej Zary > --- > # hdparm -t --direct /dev/sdb > > /dev/sdb: > Timing O_DIRECT disk reads: 4 MB in 3.78 seconds = 1.06 MB/sec > > > drivers/scsi/NCR5380.h | 1 + > drivers/scsi/g_NCR5380.c | 47 +++++++++++++++++++++++----------------------- > 2 files changed, 25 insertions(+), 23 deletions(-) > > diff --git a/drivers/scsi/NCR5380.h b/drivers/scsi/NCR5380.h > index 5092580..e3b8149 100644 > --- a/drivers/scsi/NCR5380.h > +++ b/drivers/scsi/NCR5380.h > @@ -222,6 +222,7 @@ > > #define FLAG_NO_DMA_FIXUP 1 /* No DMA errata workarounds */ > #define FLAG_NO_PSEUDO_DMA 8 /* Inhibit DMA */ > +#define FLAG_16BIT 16 /* 16-bit PDMA */ Can we give this a better name? FLAG_16BIT could be taken to mean "16-bit ISA card" but do we really want a flag for that? How about FLAG_16BIT_BUF_REG or FLAG_WORD_IO_BUF? All active flags appear in the console log, thanks to prepare_info(). It might be helpful to include this one; FLAG_DTC3181E is likely to disappear. -- > #define FLAG_LATE_DMA_SETUP 32 /* Setup NCR before DMA H/W */ > #define FLAG_TAGGED_QUEUING 64 /* as X3T9.2 spelled it */ > #define FLAG_TOSHIBA_DELAY 128 /* Allow for borken CD-ROMs */ > diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c > index fae4332..04f6c29 100644 > --- a/drivers/scsi/g_NCR5380.c > +++ b/drivers/scsi/g_NCR5380.c > @@ -331,7 +331,7 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt) > ports = ncr_53c400a_ports; > break; > case BOARD_DTC3181E: > - flags = FLAG_NO_PSEUDO_DMA; > + flags = FLAG_NO_DMA_FIXUP | FLAG_16BIT; > ports = dtc_3181e_ports; > break; > } > @@ -415,7 +415,8 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt) > hostdata->c400_blk_cnt = 1; > hostdata->c400_host_buf = 4; > } > - if (overrides[current_override].board == BOARD_NCR53C400A) { > + if (overrides[current_override].board == BOARD_NCR53C400A || > + overrides[current_override].board == BOARD_DTC3181E) { > hostdata->c400_ctl_status = 9; > hostdata->c400_blk_cnt = 10; > hostdata->c400_host_buf = 8; > @@ -434,7 +435,8 @@ static int __init generic_NCR5380_detect(struct scsi_host_template *tpnt) > goto out_unregister; > > if (overrides[current_override].board == BOARD_NCR53C400 || > - overrides[current_override].board == BOARD_NCR53C400A) > + overrides[current_override].board == BOARD_NCR53C400A || > + overrides[current_override].board == BOARD_DTC3181E) > NCR5380_write(hostdata->c400_ctl_status, CSR_BASE); > > NCR5380_maybe_reset_bus(instance); > @@ -561,11 +563,10 @@ static inline int NCR5380_pread(struct Scsi_Host *instance, unsigned char *dst, > while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY); > > #ifndef SCSI_G_NCR5380_MEM > - { > - int i; > - for (i = 0; i < 128; i++) > - dst[start + i] = NCR5380_read(hostdata->c400_host_buf); > - } > + if (hostdata->flags & FLAG_16BIT) > + insw(instance->io_port + hostdata->c400_host_buf, dst + start, 64); > + else > + insb(instance->io_port + hostdata->c400_host_buf, dst + start, 128); > #else > /* implies SCSI_G_NCR5380_MEM */ > memcpy_fromio(dst + start, > @@ -582,11 +583,10 @@ static inline int NCR5380_pread(struct Scsi_Host *instance, unsigned char *dst, > } > > #ifndef SCSI_G_NCR5380_MEM > - { > - int i; > - for (i = 0; i < 128; i++) > - dst[start + i] = NCR5380_read(hostdata->c400_host_buf); > - } > + if (hostdata->flags & FLAG_16BIT) > + insw(instance->io_port + hostdata->c400_host_buf, dst + start, 64); > + else > + insb(instance->io_port + hostdata->c400_host_buf, dst + start, 128); > #else > /* implies SCSI_G_NCR5380_MEM */ > memcpy_fromio(dst + start, > @@ -645,10 +645,10 @@ static inline int NCR5380_pwrite(struct Scsi_Host *instance, unsigned char *src, > while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY) > ; // FIXME - timeout > #ifndef SCSI_G_NCR5380_MEM > - { > - for (i = 0; i < 128; i++) > - NCR5380_write(hostdata->c400_host_buf, src[start + i]); > - } > + if (hostdata->flags & FLAG_16BIT) > + outsw(instance->io_port + hostdata->c400_host_buf, src + start, 64); > + else > + outsb(instance->io_port + hostdata->c400_host_buf, src + start, 128); > #else > /* implies SCSI_G_NCR5380_MEM */ > memcpy_toio(hostdata->iomem + NCR53C400_host_buffer, > @@ -660,12 +660,11 @@ static inline int NCR5380_pwrite(struct Scsi_Host *instance, unsigned char *src, > if (blocks) { > while (NCR5380_read(hostdata->c400_ctl_status) & CSR_HOST_BUF_NOT_RDY) > ; // FIXME - no timeout > - > #ifndef SCSI_G_NCR5380_MEM > - { > - for (i = 0; i < 128; i++) > - NCR5380_write(hostdata->c400_host_buf, src[start + i]); > - } > + if (hostdata->flags & FLAG_16BIT) > + outsw(instance->io_port + hostdata->c400_host_buf, src + start, 64); > + else > + outsb(instance->io_port + hostdata->c400_host_buf, src + start, 128); > #else > /* implies SCSI_G_NCR5380_MEM */ > memcpy_toio(hostdata->iomem + NCR53C400_host_buffer, > @@ -685,8 +684,10 @@ static inline int NCR5380_pwrite(struct Scsi_Host *instance, unsigned char *src, > /* All documentation says to check for this. Maybe my hardware is too > * fast. Waiting for it seems to work fine! KLL > */ > - while (!(i = NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ)) > + while (!(i = NCR5380_read(hostdata->c400_ctl_status) & CSR_GATED_53C80_IRQ)) { > + udelay(4); /* DTC436 chip hangs without this */ > ; // FIXME - no timeout > + } > > /* > * I know. i is certainly != 0 here but the loop is new. See previous >