On Tue, Jan 24, 2012 at 5:49 PM, Chen Gong <gong.chen@xxxxxxxxxxxxxxx> wrote: > I can understand why here C memory access model can work because ACPI table > is in physical memory zone but not in device space, but I still have > two confusion: 1)why ioremap fail but acpi_os_map_memory can work? In > essential > acpi_os_map_memory is ioremap (or precisely, ioremap_cache), right? Myron has been asking the same questions. Probably the difference is between cache and nocache. But it unclear what changed between 3.2-rc7 (where these ioremap() calls worked) and 3.3-rc1 (where they fail). > 2)since acpi_os_map_memory is io mapping too (though it is a little bit > special), read/write should work besides *C memory access*. If so, why > removing > read/write here? Some ARCH compatibility or compilation issue? It's just prettier - avoids the need for the local copies of readq()/writeq() for 32-bit systems too. -Tony -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
