On 31/03/17 04:27, Michael Ellerman wrote: > Robin Murphy <robin.murphy@xxxxxxx> writes: > >> Hi Roy, >> >> On 29/03/17 22:13, Roy Pledge wrote: >>> Use the shared-memory-pool mechanism for frame queue descriptor and >>> packed frame descriptor record area allocations. >> >> Thanks for persevering with this - in my opinion it's now looking like >> it was worth the effort :) >> >> AFAICS the ioremap_wc() that this leads to does appear to give back >> something non-cacheable on PPC (assuming "pgprot_noncached_wc" isn't >> horrendously misnamed), and "no-map" should rule out any cacheable >> linear map alias existing, so it would seem that this approach should >> avert Scott's concerns about attribute mismatches. > > How does 'no-map' translate into something being excluded from the > linear mapping? Reserved regions marked with "no-map" get memblock_remove()d by early_init_dt_alloc_reserved_memory_arch(). As I understand things, the linear map should only cover memblock areas, and it would be explicitly violating the semantics of "no-map" to still cover such a region. Robin. > > cheers > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
