> Manuel Lauss wrote:
>> Please apply this patch, as it fixes an oops when MMC-DMA and network
>> traffic are active at the same time. This seems to be a 2.6.27-only
>> the current au1xmmc code (minus the polling parts) works fine on 2.6.26.
>> Raise the DMA block size limit from 2048 bytes to the maximum supported
>> by the DMA controllers on the chip (128kB on Au1100, 4MB on Au1200).
>> This gives a small performance boost and apparently fixes an oops when
>> MMC-DMA and network traffic are active at the same time.
>> Signed-off-by: Manuel Lauss <firstname.lastname@example.org>
>> diff --git a/drivers/mmc/host/au1xmmc.c b/drivers/mmc/host/au1xmmc.c
>> index 99b2091..dd414f1 100644
>> --- a/drivers/mmc/host/au1xmmc.c
>> +++ b/drivers/mmc/host/au1xmmc.c
>> @@ -61,7 +61,13 @@
>> /* Hardware definitions */
>> #define AU1XMMC_DESCRIPTOR_COUNT 1
>> -#define AU1XMMC_DESCRIPTOR_SIZE 2048
>> +/* max DMA seg size: 64kB on Au1100, 4MB on Au1200 */
> So, it's 64 or 128 KB? KB since k prefix usualy means decimal kilo... :-)
I'm not so sure myself. If I understand the datasheet correctly, the Au1100
DMA ctrl always transfers 2 segments of up to 64KB each. I'll correct the
commit-text and resend. Someone else with Au1100 hardware can figure that
out if they want; for now this only matter for Au1200 DMA.
(And I refuse to acknowledge the existence of that 'kibibyte' crap ;-) )
> WBR, Sergei
Thank you Sergei,