clocksource: hyper-v: Add TSC page support for root partition

Microsoft Hypervisor root partition has to map the TSC page specified
by the hypervisor, instead of providing the page to the hypervisor like
it's done in the guest partitions.

However, it's too early to map the page when the clock is initialized, so, the
actual mapping is happening later.

Signed-off-by: Stanislav Kinsburskiy <[email protected]>
CC: "K. Y. Srinivasan" <[email protected]>
CC: Haiyang Zhang <[email protected]>
CC: Wei Liu <[email protected]>
CC: Dexuan Cui <[email protected]>
CC: Thomas Gleixner <[email protected]>
CC: Ingo Molnar <[email protected]>
CC: Borislav Petkov <[email protected]>
CC: Dave Hansen <[email protected]>
CC: [email protected]
CC: "H. Peter Anvin" <[email protected]>
CC: Daniel Lezcano <[email protected]>
CC: [email protected]
CC: [email protected]
Reviewed-by: Michael Kelley <[email protected]>
Reviewed-by: Anirudh Rayabharam <[email protected]>
Link: https://lore.kernel.org/r/166759443644.385891.15921594265843430260.stgit@skinsburskii-cloud-desktop.internal.cloudapp.net
Signed-off-by: Wei Liu <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/clocksource/hyperv_timer.h b/include/clocksource/hyperv_timer.h
index 3078d23faaea..783701a2102d 100644
--- a/include/clocksource/hyperv_timer.h
+++ b/include/clocksource/hyperv_timer.h
@@ -31,6 +31,7 @@ extern void hv_stimer_global_cleanup(void);
 extern void hv_stimer0_isr(void);
 
 extern void hv_init_clocksource(void);
+extern void hv_remap_tsc_clocksource(void);
 
 extern unsigned long hv_get_tsc_pfn(void);
 extern struct ms_hyperv_tsc_page *hv_get_tsc_page(void);