diff options
| author | Matt Fleming <matt.fleming@intel.com> | 2012-09-07 18:28:04 +0100 |
|---|---|---|
| committer | Matt Fleming <matt.fleming@intel.com> | 2012-10-30 10:39:19 +0000 |
| commit | 185034e72d591f9465e5e18f937ed642e7ea0070 (patch) | |
| tree | ecb81fad559d790db1a0d390a8fa6e209662c315 /arch/x86/include/asm/efi.h | |
| parent | 53b87cf088e2ea68d7c59619d0214cc15bb76133 (diff) | |
x86, efi: 1:1 pagetable mapping for virtual EFI calls
Some firmware still needs a 1:1 (virt->phys) mapping even after we've
called SetVirtualAddressMap(). So install the mapping alongside our
existing kernel mapping whenever we make EFI calls in virtual mode.
This bug was discovered on ASUS machines where the firmware
implementation of GetTime() accesses the RTC device via physical
addresses, even though that's bogus per the UEFI spec since we've
informed the firmware via SetVirtualAddressMap() that the boottime
memory map is no longer valid.
This bug seems to be present in a lot of consumer devices, so there's
not a lot we can do about this spec violation apart from workaround
it.
Cc: JérômeCarretero <cJ-ko@zougloub.eu>
Cc: Vasco Dias <rafa.vasco@gmail.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Diffstat (limited to 'arch/x86/include/asm/efi.h')
| -rw-r--r-- | arch/x86/include/asm/efi.h | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index c9dcc181d4d..ae3bf3b8da7 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -69,23 +69,37 @@ extern u64 efi_call6(void *fp, u64 arg1, u64 arg2, u64 arg3, efi_call6((void *)(f), (u64)(a1), (u64)(a2), (u64)(a3), \ (u64)(a4), (u64)(a5), (u64)(a6)) +extern unsigned long efi_call_virt_prelog(void); +extern void efi_call_virt_epilog(unsigned long); + +#define efi_callx(x, func, ...) \ + ({ \ + efi_status_t __status; \ + unsigned long __pgd; \ + \ + __pgd = efi_call_virt_prelog(); \ + __status = efi_call##x(func, __VA_ARGS__); \ + efi_call_virt_epilog(__pgd); \ + __status; \ + }) + #define efi_call_virt0(f) \ - efi_call0((void *)(efi.systab->runtime->f)) + efi_callx(0, (void *)(efi.systab->runtime->f)) #define efi_call_virt1(f, a1) \ - efi_call1((void *)(efi.systab->runtime->f), (u64)(a1)) + efi_callx(1, (void *)(efi.systab->runtime->f), (u64)(a1)) #define efi_call_virt2(f, a1, a2) \ - efi_call2((void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2)) + efi_callx(2, (void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2)) #define efi_call_virt3(f, a1, a2, a3) \ - efi_call3((void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ + efi_callx(3, (void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ (u64)(a3)) #define efi_call_virt4(f, a1, a2, a3, a4) \ - efi_call4((void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ + efi_callx(4, (void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ (u64)(a3), (u64)(a4)) #define efi_call_virt5(f, a1, a2, a3, a4, a5) \ - efi_call5((void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ + efi_callx(5, (void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ (u64)(a3), (u64)(a4), (u64)(a5)) #define efi_call_virt6(f, a1, a2, a3, a4, a5, a6) \ - efi_call6((void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ + efi_callx(6, (void *)(efi.systab->runtime->f), (u64)(a1), (u64)(a2), \ (u64)(a3), (u64)(a4), (u64)(a5), (u64)(a6)) extern void __iomem *efi_ioremap(unsigned long addr, unsigned long size, |