Bug#395031: Kernel complains about DMA

[Panagiotis Issaris <takis.issaris@uhasselt.be>]

Hi,

On Wed, Oct 25, 2006 at 06:25:09AM +0200, Frederik Schueler wrote:
> Hello,
> 
> On Tue, Oct 24, 2006 at 04:30:50PM +0200, Panagiotis Issaris wrote:
> > Oct 24 11:00:25 localhost kernel: CMD643: IDE controller at PCI slot 0000:00:08.0
> > Oct 24 11:00:25 localhost kernel: CMD643: chipset revision 0
> > Oct 24 11:00:25 localhost kernel: CMD643: not 100%% native mode: will probe irqs later
> > Oct 24 11:00:25 localhost kernel: CMD643: simplex device: DMA forced
>                                             ^^^^^^^^^^^^^^
> > Oct 24 11:00:25 localhost kernel:     ide0: BM-DMA at 0xfe00-0xfe07, BIOS settings: hda:pio, hdb:pio
> > Oct 24 11:00:25 localhost kernel:     ide1: BM-DMA at 0xfe08-0xfe0f, BIOS settings: hdc:pio, hdd:pio
> 
> I doubt this box will do DMA, ever. AFAIK the chipset just does not
> support it.

Apparently drivers/ide/setup-pci.c forces it to use DMA as there's a switch in
which certain chipsets are forced to use DMA, while the default handling is to
disable it.

Thanks for your useful reply!

With friendly regards,
Takis

-- 
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diff --git a/drivers/ide/setup-pci.c b/drivers/ide/setup-pci.c
index 0719b64..5a7b6f6 100644
--- a/drivers/ide/setup-pci.c
+++ b/drivers/ide/setup-pci.c
@@ -226,7 +226,6 @@ #endif /* CONFIG_BLK_DEV_IDEDMA_FORCED *
                        case PCI_DEVICE_ID_AL_M5219:
                        case PCI_DEVICE_ID_AL_M5229:
                        case PCI_DEVICE_ID_AMD_VIPER_7409:
-                       case PCI_DEVICE_ID_CMD_643:
                        case PCI_DEVICE_ID_SERVERWORKS_CSB5IDE:
                        case PCI_DEVICE_ID_REVOLUTION:
                                simplex_stat = hwif->INB(dma_base + 2);