grub/grub-core/kern/riscv/efi/init.c
Alexander Graf 8ce194d068 RISC-V: Add auxiliary files
To support a new architecture we need to provide a few helper functions
for memory, cache, timer, etc support.

This patch adds the remainders of those. Some bits are still disabled,
as I couldn't guarantee that we're always running on models / in modes
where the respective hardware is available.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2020-09-21 16:43:54 -04:00

76 lines
1.9 KiB
C

/* init.c - initialize a riscv-based EFI system */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2018 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 timer_frequency_in_khz;
static grub_uint64_t
grub_efi_get_time_ms (void)
{
grub_uint64_t tmr;
#if __riscv_xlen == 64
asm volatile ("rdcycle %0" : "=r" (tmr));
#else
grub_uint32_t lo, hi, tmp;
asm volatile (
"1:\n"
"rdcycleh %0\n"
"rdcycle %1\n"
"rdcycleh %2\n"
"bne %0, %2, 1b"
: "=&r" (hi), "=&r" (lo), "=&r" (tmp));
tmr = ((grub_uint64_t)hi << 32) | lo;
#endif
return tmr / timer_frequency_in_khz;
}
void
grub_machine_init (void)
{
grub_uint64_t time_before, time_after;
grub_efi_init ();
/* Calculate timer frequency */
timer_frequency_in_khz = 1;
time_before = grub_efi_get_time_ms();
grub_efi_stall(1000);
time_after = grub_efi_get_time_ms();
timer_frequency_in_khz = time_after - time_before;
grub_install_get_time_ms (grub_efi_get_time_ms);
}
void
grub_machine_fini (int flags)
{
if (!(flags & GRUB_LOADER_FLAG_NORETURN))
return;
grub_efi_fini ();
}