grub/grub-core/kern/arm/efi/init.c
Mark Salter 7eb27a49e9 arm-efi: Reduce timer event frequency by 10
Timer event to keep grub msec counter was running at 1000HZ. This was too
fast for UEFI timer driver and resulted in a 10x slowdown in grub time
versus wallclock. Reduce the timer event frequency and increase tick
increment accordingly to keep better time.
2016-01-07 20:54:20 +01:00

74 lines
1.9 KiB
C

/* init.c - initialize an arm-based EFI system */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2013 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/env.h>
#include <grub/kernel.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/time.h>
#include <grub/efi/efi.h>
#include <grub/loader.h>
static grub_uint64_t tmr;
static grub_efi_event_t tmr_evt;
static grub_uint64_t
grub_efi_get_time_ms (void)
{
return tmr;
}
static void
increment_timer (grub_efi_event_t event __attribute__ ((unused)),
void *context __attribute__ ((unused)))
{
tmr += 10;
}
void
grub_machine_init (void)
{
grub_efi_boot_services_t *b;
grub_efi_init ();
b = grub_efi_system_table->boot_services;
efi_call_5 (b->create_event, GRUB_EFI_EVT_TIMER | GRUB_EFI_EVT_NOTIFY_SIGNAL,
GRUB_EFI_TPL_CALLBACK, increment_timer, NULL, &tmr_evt);
efi_call_3 (b->set_timer, tmr_evt, GRUB_EFI_TIMER_PERIODIC, 100000);
grub_install_get_time_ms (grub_efi_get_time_ms);
}
void
grub_machine_fini (int flags)
{
grub_efi_boot_services_t *b;
if (!(flags & GRUB_LOADER_FLAG_NORETURN))
return;
b = grub_efi_system_table->boot_services;
efi_call_3 (b->set_timer, tmr_evt, GRUB_EFI_TIMER_CANCEL, 0);
efi_call_1 (b->close_event, tmr_evt);
grub_efi_fini ();
}