Messages in this thread | | | Subject | Re: DMA and Cache coherency on machines without hardware enforced | From | Jes Sorensen <> | Date | 02 Dec 1999 14:05:49 +0100 |
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>>>>> "Ingo" == Ingo Molnar <mingo@chiara.csoma.elte.hu> writes:
Ingo> On Wed, 1 Dec 1999, Pete Zaitcev wrote:
>> >page = __get_free_pages(whatever, order); >ptr = >> ioremap_nocache(virt_to_phys(page), 1 << (order+PAGE_SHIFT)); >> >> When was ioremap_nocache() introduced and was it sprinked with a >> penguin pee?
Ingo> well, 2 or 3 years ago, in the late 2.0 kernels.
I still see a need for a get_free_coherent_page() for use in cases where you want to share physical memory with devices. On coherent architectures get_free_page() does just fine today, but on machines like the m68k it does not. Having a standard interface would making device drivers portable a lot easier.
Question is which API would be the most appropriate.
Jes
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