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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 bacef661ac ("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 f026cfa82f. 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 <jbeulich@suse.com>
Tested-by: Matt Fleming <matt.fleming@intel.com>
Acked-by: Matthew Garrett <mjg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com> [added commit history]
This commit is contained in:
Jan Beulich 2012-05-25 16:20:31 +01:00 committed by Matt Fleming
parent da5a108d05
commit bd52276fa1
4 changed files with 14 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/mm/pageattr.c
View File

@ -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);

30
arch/x86/platform/efi/efi.c
View File

@ -235,22 +235,7 @@ static efi_status_t __init phys_efi_set_virtual_address_map(
return status;
}
static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
efi_time_cap_t *tc)
{
unsigned long flags;
efi_status_t status;
spin_lock_irqsave(&rtc_lock, flags);
efi_call_phys_prelog();
status = efi_call_phys2(efi_phys.get_time, virt_to_phys(tm),
virt_to_phys(tc));
efi_call_phys_epilog();
spin_unlock_irqrestore(&rtc_lock, flags);
return status;
}
int efi_set_rtc_mmss(unsigned long nowtime)
static int efi_set_rtc_mmss(unsigned long nowtime)
{
int real_seconds, real_minutes;
efi_status_t status;
@ -279,7 +264,7 @@ int efi_set_rtc_mmss(unsigned long nowtime)
return 0;
}
unsigned long efi_get_time(void)
static unsigned long efi_get_time(void)
{
efi_status_t status;
efi_time_t eft;
@ -635,18 +620,13 @@ static int __init efi_runtime_init(void)
}
/*
* We will only need *early* access to the following
* two EFI runtime services before set_virtual_address_map
* EFI runtime service before set_virtual_address_map
* is invoked.
*/
efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
efi_phys.set_virtual_address_map =
(efi_set_virtual_address_map_t *)
runtime->set_virtual_address_map;
/*
* Make efi_get_time can be called before entering
* virtual mode.
*/
efi.get_time = phys_efi_get_time;
early_iounmap(runtime, sizeof(efi_runtime_services_t));
return 0;
@ -734,12 +714,10 @@ void __init efi_init(void)
efi_enabled = 0;
return;
}
#ifdef CONFIG_X86_32
if (efi_native) {
x86_platform.get_wallclock = efi_get_time;
x86_platform.set_wallclock = efi_set_rtc_mmss;
}
#endif
#if EFI_DEBUG
print_efi_memmap();

2
include/linux/efi.h
View File

@ -516,8 +516,6 @@ extern u64 efi_mem_attribute (unsigned long phys_addr, unsigned long size);
extern int __init efi_uart_console_only (void);
extern void efi_initialize_iomem_resources(struct resource *code_resource,
struct resource *data_resource, struct resource *bss_resource);
extern unsigned long efi_get_time(void);
extern int efi_set_rtc_mmss(unsigned long nowtime);
extern void efi_reserve_boot_services(void);
extern struct efi_memory_map memmap;

8
init/main.c
View File

@ -461,6 +461,10 @@ static void __init mm_init(void)
percpu_init_late();
pgtable_cache_init();
vmalloc_init();
#ifdef CONFIG_X86
if (efi_enabled)
efi_enter_virtual_mode();
#endif
}
asmlinkage void __init start_kernel(void)
@ -601,10 +605,6 @@ asmlinkage void __init start_kernel(void)
calibrate_delay();
pidmap_init();
anon_vma_init();
#ifdef CONFIG_X86
if (efi_enabled)
efi_enter_virtual_mode();
#endif
thread_info_cache_init();
cred_init();
fork_init(totalram_pages);