Messages in this thread | | | From | Ohad Ben-Cohen <> | Date | Mon, 10 Sep 2012 15:48:57 +0300 | Subject | Re: Remoteproc: Translating between host and device addresses. |
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Hi Sjur,
On Tue, Aug 14, 2012 at 8:06 PM, Sjur BRENDELAND <sjur.brandeland@stericsson.com> wrote: > One way for the device to figure out the translation between > host-physical and device-address is to peek into some CarveOut > resource entry and compute this translation. Because a CarveOut > resource entry contains both the host-physical-address and the > device address for the same memory location. But this feels > like a workaround, shouldn't we make a more explicit way of > communicating this mapping between host-physical and device > addresses?
Yes, we should. The plan is, when relevant, to switch to the IOMMU-based DMA API to allocate device addresses (by programming the IOMMUs automatically), and stop sending physical addresses remotely.
For OMAP, btw, we will still provide those device->physical translation resource entries, because OMAP4 has a few remote components that access the host-physical memory directly.
Thanks, Ohad.
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