lkml.org 
[lkml]   [2007]   [Aug]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 2.6.22.y] ieee1394: revert "sbp2: enforce 32bit DMA mapping"
    Stefan Richter wrote:
    > Date: Wed, 1 Aug 2007 20:30:36 +0200 (CEST)
    > From: Stefan Richter <stefanr@s5r6.in-berlin.de>
    > Subject: ieee1394: revert "sbp2: enforce 32bit DMA mapping"
    >
    > Revert commit 0555659d63c285ceb7ead3115532e1b71b0f27a7 from 2.6.22-rc1.
    > The dma_set_mask call somehow failed on a PowerMac G5, PPC64:
    > http://lkml.org/lkml/2007/8/1/344
    >
    > Should there ever occur a DMA mapping beyond the physical DMA range, a
    > proper SBP-2 firmware will report transport errors. So let's leave it
    > at that.

    Isn't this a rather poor workaround? All this means is that if we fail
    to set a 32-bit DMA mask, we're likely to blow up at runtime instead of
    at initialization time, when we get a DMA mapping over 4GB.

    If setting 32-bit DMA mask fails on ppc64, that sounds like a problem
    with the DMA implementation on that architecture. There are enough cards
    out there that only support 32-bit DMA that this really needs to work..

    >
    > Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
    > Tested-by: Olaf Hering <olh@suse.de>
    > ---
    > Same as commit a9c2f18800753c82c45fc13b27bdc148849bdbb2.
    >
    > drivers/ieee1394/sbp2.c | 5 -----
    > 1 file changed, 5 deletions(-)
    >
    > Index: linux-2.6.22/drivers/ieee1394/sbp2.c
    > ===================================================================
    > --- linux-2.6.22.orig/drivers/ieee1394/sbp2.c
    > +++ linux-2.6.22/drivers/ieee1394/sbp2.c
    > @@ -774,11 +774,6 @@ static struct sbp2_lu *sbp2_alloc_device
    > SBP2_ERR("failed to register lower 4GB address range");
    > goto failed_alloc;
    > }
    > -#else
    > - if (dma_set_mask(hi->host->device.parent, DMA_32BIT_MASK)) {
    > - SBP2_ERR("failed to set 4GB DMA mask");
    > - goto failed_alloc;
    > - }
    > #endif
    > }
    >
    >

    --
    Robert Hancock Saskatoon, SK, Canada
    To email, remove "nospam" from hancockr@nospamshaw.ca
    Home Page: http://www.roberthancock.com/

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2007-08-04 19:17    [W:0.037 / U:0.152 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site