[PATCH] x86-64/efi: Use EFI to deal with platform wall clock (again)
From: Jan Beulich
Date: Fri May 25 2012 - 11:20:31 EST
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 <jbeulich@xxxxxxxx>
Tested-by: Matt Fleming <matt.fleming@xxxxxxxxx>
Acked-by: Matthew Garrett <mjg@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Signed-off-by: Matt Fleming <matt.fleming@xxxxxxxxx> [added commit history]
---
arch/x86/mm/pageattr.c | 10 ++++++----
arch/x86/platform/efi/efi.c | 30 ++++--------------------------
include/linux/efi.h | 2 --
init/main.c | 8 ++++----
4 files changed, 14 insertions(+), 36 deletions(-)
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);
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index aded2a9..7578344 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -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();
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 337aefb..5e2308d 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -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;
diff --git a/init/main.c b/init/main.c
index db34c0e..5297109 100644
--- a/init/main.c
+++ b/init/main.c
@@ -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)
@@ -602,10 +606,6 @@ 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);
--
1.7.11.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/