Russell King wrote:
> On Thu, Mar 02, 2006 at 10:52:04AM +0100, Pierre Ossman wrote:
>
>> Russell King wrote:
>>
>>> I think you're asking Jens that question - I know of no way to tell
>>> the block layer that clustering is fine for normal but not highmem.
>>>
>> That wasn't what I meant. What I was referring to was disabling highmem
>> altogether, the way that is done now through looking at the dma mask.
>>
>
> You need to set your struct device's dma_mask appropriately:
>
> u64 limit = BLK_BOUNCE_HIGH;
>
> if (host->dev->dma_mask && *host->dev->dma_mask)
> limit = *host->dev->dma_mask;
>
> blk_queue_bounce_limit(mq->queue, limit);
>
> Hence, if dma_mask is a NULL pointer or zero, highmem will be bounced.
>
This I know. My beef is the readability of:
if (do_dma)
*dev->dma_mask = DEVICE_DMA_MASK;
else
*dev->dma_mask = 0;
I.e. we use dma_mask even though we don't do DMA.
> Neither PNP nor your platform device sets dma_mask, so highmem will
> always be bounced in the case of wbsd - which from what you write above
> is what you require anyway.
>
>
wbsd isn't the issue, sdhci is. PCI sets a 32-bit mask by default so I
end up with highmem pages even when I'm not doing DMA.
Rgds
Pierre
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
