Re: dma_alloc_coherent() on PPC32: physical addresses above 2G possible?

On Sun, 20 Jul 2008 21:25:51 +0200
Stefan Richter [off-list ref] wrote:

Arjan van de Ven wrote:

quoted

On Sun, 20 Jul 2008 20:36:23 +0200
Stefan Richter [off-list ref] wrote:

quoted

PS:  I don't want to set the DMA mask of this device to
DMA_31BIT_MASK because that would be detrimental to other functions
of the device. It's a TI TSB43AB22A FireWire controller.

Hi,

just want to mention that you can set the coherent mask separately
from the generic mask... is that sufficient for your load?
(you can even set it just for this allocation..)

Hmm.  Would that be done this way?
During probe:

	if (chip_is_tsb43ab22a) {
		if (dma_supported(dev, DMA_31BIT_MASK))
			chip->needs_dma_mask_workaround = 1;
		else
			chip->needs_some_other_workaround = 1;
	}

btw it might be nicer to make this

chip->something_special_mask = DMA_31BIT_MASK;

then you can just use the mask from this struct rather than another
check


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