| Date | Wed, 09 Jan 2013 16:12:31 -0700 | From | Stephen Warren <> | Subject | Re: [PATCH 05/14] lib: Add I/O map cache implementation |
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On 01/09/2013 03:10 PM, Arnd Bergmann wrote: > On Wednesday 09 January 2013, Thierry Reding wrote: >> What happens on Tegra is that we need to map 256 MiB of physical memory >> to access all the PCIe extended configuration space. However, ioremap() >> on such a large region fails if not enough vmalloc() space is available. >> >> This was observed when somebody tested this on CardHu which has a 1 GiB >> of RAM and therefore remapping the full 256 MiB fails. ... > Have you checked if the hardware supports an alternative config > space access mechanism that does not depend on a huge address range? > A lot of them provide an index/data register pair somewhere, as the > original PC implementation did.
That would be nice, but I've talked to the HW engineers, and there's no indication that any alternative mechanism exists.
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