x86/platform: Add a wallclock_init func to x86_platforms ops

Some wall clock devices use MMIO based HW register, this new
function will give them a chance to do some initialization work
before their get/set_time service get called.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 6 insertions, 0 deletions

diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index d3d859035af..f864fbe474c 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -152,6 +152,7 @@ struct x86_cpuinit_ops {
 /**
  * struct x86_platform_ops - platform specific runtime functions
  * @calibrate_tsc:              calibrate TSC
+ * @wallclock_init:             init the wallclock device
  * @get_wallclock:              get time from HW clock like RTC etc.
  * @set_wallclock:              set time back to HW clock
  * @is_untracked_pat_range      exclude from PAT logic
@@ -160,6 +161,7 @@ struct x86_cpuinit_ops {
  */
 struct x86_platform_ops {
         unsigned long (*calibrate_tsc)(void);
+        void (*wallclock_init)(void);
         unsigned long (*get_wallclock)(void);
         int (*set_wallclock)(unsigned long nowtime);
         void (*iommu_shutdown)(void);
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index afaf38447ef..cf0ef986cb6 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1045,6 +1045,8 @@ void __init setup_arch(char **cmdline_p)
 
         x86_init.timers.wallclock_init();
 
+        x86_platform.wallclock_init();
+
         mcheck_init();
 
         arch_init_ideal_nops();
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index 6f164bd5e14..701c7be442f 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -27,6 +27,7 @@ void __init x86_init_uint_noop(unsigned int unused) { }
 void __init x86_init_pgd_noop(pgd_t *unused) { }
 int __init iommu_init_noop(void) { return 0; }
 void iommu_shutdown_noop(void) { }
+void wallclock_init_noop(void) { }
 
 /*
  * The platform setup functions are preset with the default functions
@@ -97,6 +98,7 @@ static int default_i8042_detect(void) { return 1; };
 
 struct x86_platform_ops x86_platform = {
         .calibrate_tsc                  = native_calibrate_tsc,
+        .wallclock_init                 = wallclock_init_noop,
         .get_wallclock                  = mach_get_cmos_time,
         .set_wallclock                  = mach_set_rtc_mmss,
         .iommu_shutdown                 = iommu_shutdown_noop,