From bd52276fa1d420c3a504b76ffaaa1642cc79d4c4 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Fri, 25 May 2012 16:20:31 +0100 Subject: x86-64/efi: Use EFI to deal with platform wall clock (again) Other than ix86, x86-64 on EFI so far didn't set the {g,s}et_wallclock accessors to the EFI routines, thus incorrectly using raw RTC accesses instead. Simply removing the #ifdef around the respective code isn't enough, however: While so far early get-time calls were done in physical mode, this doesn't work properly for x86-64, as virtual addresses would still need to be set up for all runtime regions (which wasn't the case on the system I have access to), so instead the patch moves the call to efi_enter_virtual_mode() ahead (which in turn allows to drop all code related to calling efi-get-time in physical mode). Additionally the earlier calling of efi_set_executable() requires the CPA code to cope, i.e. during early boot it must be avoided to call cpa_flush_array(), as the first thing this function does is a BUG_ON(irqs_disabled()). Also make the two EFI functions in question here static - they're not being referenced elsewhere. History: This commit was originally merged as bacef661acdb ("x86-64/efi: Use EFI to deal with platform wall clock") but it resulted in some ASUS machines no longer booting due to a firmware bug, and so was reverted in f026cfa82f62. A pre-emptive fix for the buggy ASUS firmware was merged in 03a1c254975e ("x86, efi: 1:1 pagetable mapping for virtual EFI calls") so now this patch can be reapplied. Signed-off-by: Jan Beulich Tested-by: Matt Fleming Acked-by: Matthew Garrett Cc: Ingo Molnar Cc: Peter Zijlstra Cc: H. Peter Anvin Signed-off-by: Matt Fleming [added commit history] --- arch/x86/mm/pageattr.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'arch/x86/mm') diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index a718e0d..931930a 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -919,11 +919,13 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages, /* * On success we use clflush, when the CPU supports it to - * avoid the wbindv. If the CPU does not support it and in the - * error case we fall back to cpa_flush_all (which uses - * wbindv): + * avoid the wbindv. If the CPU does not support it, in the + * error case, and during early boot (for EFI) we fall back + * to cpa_flush_all (which uses wbinvd): */ - if (!ret && cpu_has_clflush) { + if (early_boot_irqs_disabled) + __cpa_flush_all((void *)(long)cache); + else if (!ret && cpu_has_clflush) { if (cpa.flags & (CPA_PAGES_ARRAY | CPA_ARRAY)) { cpa_flush_array(addr, numpages, cache, cpa.flags, pages); -- cgit v1.1