Messages in this thread | | | Subject | Re: [RESEND PATCH v2 14/15] ASoC: qcom: apq8096: Add db820c machine driver | From | Srinivas Kandagatla <> | Date | Thu, 4 Jan 2018 09:25:24 +0000 |
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On 03/01/18 19:41, Stephen Boyd wrote: >>>> + ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); >>> Why do we need to do this? Can you add some sort of comment in the code >>> about why? >> Even though dsp supports 64 bit addresses, but the sid sits at >> offset of 32, which brings this restriction of supporting only 32 >> bit iova. >> > Doesn't the dsp have an iommu in place to make the address > translation from 64 to 32 bits transparent? I thought this was > what dma-ranges and iommu binding was for, but I'm not well > versed on all the details here. Thanks for reminding, dma-ranges would work too, I will give that a go in next version.
--srini
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