From 7bc90e01c3f66c137e7e761f574bbf883087d590 Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Fri, 28 Sep 2012 17:56:08 -0700 Subject: efi: Add a function to look up existing IO memory mappings The EFI initialization creates virtual mappings for EFI boot services memory, so if a driver wants to access EFI boot services memory, it cannot call ioremap itself; doing so will trip the WARN about mapping RAM twice. Thus, a driver accessing EFI boot services memory must do so via the existing mapping already created during EFI intiialization. Since the EFI code already maintains a memory map for that memory, add a function efi_lookup_mapped_addr to look up mappings in that memory map. Signed-off-by: Josh Triplett Link: http://lkml.kernel.org/r/0eb48ae012797912874919110660ad420b90268b.1348876882.git.josh@joshtriplett.org Signed-off-by: H. Peter Anvin --- include/linux/efi.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/efi.h') diff --git a/include/linux/efi.h b/include/linux/efi.h index 5782114f4838..fff135d9375e 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -501,6 +501,7 @@ extern void efi_free_boot_services(void); #else static inline void efi_free_boot_services(void) {} #endif +extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr); extern u64 efi_get_iobase (void); extern u32 efi_mem_type (unsigned long phys_addr); extern u64 efi_mem_attributes (unsigned long phys_addr); -- cgit v1.2.3