101 lines
2.5 KiB
C
101 lines
2.5 KiB
C
/*
|
|
* GRUB -- GRand Unified Bootloader
|
|
* Copyright (C) 2016 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/mm.h>
|
|
#include <grub/machine/kernel.h>
|
|
#include <grub/types.h>
|
|
#include <grub/err.h>
|
|
#include <grub/time.h>
|
|
#include <grub/fdtbus.h>
|
|
#include <grub/misc.h>
|
|
|
|
grub_uint64_t
|
|
grub_armv7_get_timer_value(void);
|
|
|
|
grub_uint32_t
|
|
grub_armv7_get_timer_frequency(void);
|
|
|
|
grub_uint32_t
|
|
grub_arm_pfr1(void);
|
|
|
|
static int have_timer = 0;
|
|
static volatile grub_uint32_t *sp804_regs;
|
|
|
|
static grub_uint64_t
|
|
sp804_get_time_ms (void)
|
|
{
|
|
static grub_uint32_t high, last_low;
|
|
grub_uint32_t low = ~sp804_regs[1];
|
|
if (last_low > low)
|
|
high++;
|
|
last_low = low;
|
|
return grub_divmod64 ((((grub_uint64_t) high) << 32) | low,
|
|
1000, 0);
|
|
}
|
|
|
|
static grub_err_t
|
|
sp804_attach(const struct grub_fdtbus_dev *dev)
|
|
{
|
|
if (have_timer)
|
|
return GRUB_ERR_NONE;
|
|
sp804_regs = grub_fdtbus_map_reg (dev, 0, 0);
|
|
if (!grub_fdtbus_is_mapping_valid (sp804_regs))
|
|
return grub_error (GRUB_ERR_IO, "could not map sp804: %p", sp804_regs);
|
|
grub_install_get_time_ms (sp804_get_time_ms);
|
|
have_timer = 1;
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
|
|
struct grub_fdtbus_driver sp804 =
|
|
{
|
|
.compatible = "arm,sp804",
|
|
.attach = sp804_attach
|
|
};
|
|
|
|
static grub_uint32_t timer_frequency_in_khz;
|
|
|
|
static grub_uint64_t
|
|
generic_get_time_ms (void)
|
|
{
|
|
return grub_divmod64 (grub_armv7_get_timer_value(), timer_frequency_in_khz, 0);
|
|
}
|
|
|
|
static int
|
|
try_generic_timer (void)
|
|
{
|
|
if (((grub_arm_pfr1 () >> 16) & 0xf) != 1)
|
|
return 0;
|
|
grub_printf ("freq = %x\n", grub_armv7_get_timer_frequency());
|
|
timer_frequency_in_khz = 0x016e3600 / 1000; //grub_armv7_get_timer_frequency() / 1000;
|
|
if (timer_frequency_in_khz == 0)
|
|
return 0;
|
|
grub_install_get_time_ms (generic_get_time_ms);
|
|
have_timer = 1;
|
|
return 1;
|
|
}
|
|
|
|
void
|
|
grub_machine_timer_init (void)
|
|
{
|
|
grub_fdtbus_register (&sp804);
|
|
|
|
if (!have_timer)
|
|
try_generic_timer ();
|
|
if (!have_timer)
|
|
grub_fatal ("No timer found");
|
|
}
|