Re: [PATCH 19/19] ide: use PIO/MMIO operations directly where possible

From: Bartlomiej Zolnierkiewicz
Date: Fri Jan 12 2007 - 09:20:05 EST


On 1/12/07, Alan <alan@xxxxxxxxxxxxxxxxxxx> wrote:
On Fri, 12 Jan 2007 05:28:07 +0100
Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx> wrote:

> [PATCH] ide: use PIO/MMIO operations directly where possible
>
> This results in smaller/faster/simpler code and allows future optimizations.
> Also remove no longer needed ide[_mm]_{inl,outl}() and ide_hwif_t.{INL,OUTL}.
>
> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>

> --- a.orig/drivers/ide/ide-dma.c
> +++ a/drivers/ide/ide-dma.c
> @@ -565,7 +565,10 @@ int ide_dma_setup(ide_drive_t *drive)
> }
>
> /* PRD table */
> - hwif->OUTL(hwif->dmatable_dma, hwif->dma_prdtable);
> + if (hwif->mmio == 2)
> + writel(hwif->dmatable_dma, (void __iomem *)hwif->dma_prdtable);
> + else
> + outl(hwif->dmatable_dma, hwif->dma_prdtable);


This should simply be if (hwif->mmio)

mmio = 1 is still used by some amiga and other oddments and indicates
mmio in old form. I don't think this causes a bug as they don't use the
DMA layer, but its a bug waiting to happen if the mmio==1 case doesn't
get handled correctly or BUG()

mmio = 1 isn't used in the current IDE code and we have BUG_ON()
for it in ide.c:ide_hwif_request_regions() so the above change is safe.

Anyway thanks for bringing mmio = 1 issue - it can be converted
to flag now (will let us avoid similar confusions in the future).

Bart
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