From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Fri, 10 Oct 2014 11:11:09 +0200 Subject: [PATCH] calibrate_tsc(): use the Stall() EFI boot service on GRUB_MACHINE_EFI Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1150698 HyperV Gen2 virtual machines have no PIT; guest code should rely on UEFI services instead. Signed-off-by: RHEL Ninjas --- grub-core/kern/i386/tsc.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/grub-core/kern/i386/tsc.c b/grub-core/kern/i386/tsc.c index 3a4cae601d0..e49964833ca 100644 --- a/grub-core/kern/i386/tsc.c +++ b/grub-core/kern/i386/tsc.c @@ -26,9 +26,14 @@ #include #include #ifdef GRUB_MACHINE_XEN -#include +# include #else -#include +# ifdef GRUB_MACHINE_EFI +# include +# include +# else +# include +# endif #endif #include @@ -72,8 +77,14 @@ grub_cpu_is_tsc_supported (void) #ifndef GRUB_MACHINE_XEN static void -grub_pit_wait (grub_uint16_t tics) +grub_stall (grub_uint16_t tics) { +# ifdef GRUB_MACHINE_EFI + grub_uint64_t microseconds; + + microseconds = (grub_uint64_t)tics * 1000 * 1000 * 3 / 3579545; + efi_call_1 (grub_efi_system_table->boot_services->stall, microseconds); +# else /* Disable timer2 gate and speaker. */ grub_outb (grub_inb (GRUB_PIT_SPEAKER_PORT) & ~ (GRUB_PIT_SPK_DATA | GRUB_PIT_SPK_TMR2), @@ -97,6 +108,7 @@ grub_pit_wait (grub_uint16_t tics) grub_outb (grub_inb (GRUB_PIT_SPEAKER_PORT) & ~ (GRUB_PIT_SPK_DATA | GRUB_PIT_SPK_TMR2), GRUB_PIT_SPEAKER_PORT); +# endif } #endif @@ -119,7 +131,7 @@ calibrate_tsc (void) grub_uint64_t end_tsc; tsc_boot_time = grub_get_tsc (); - grub_pit_wait (0xffff); + grub_stall (0xffff); end_tsc = grub_get_tsc (); grub_tsc_rate = grub_divmod64 ((55ULL << 32), end_tsc - tsc_boot_time, 0);