mirror of https://gitee.com/openkylin/linux.git
66 lines
1.6 KiB
C
66 lines
1.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright IBM Corp. 2007, 2018
|
|
*/
|
|
|
|
/*
|
|
* Early setup functions which may not rely on an initialized bss
|
|
* section. The last thing that is supposed to happen here is
|
|
* initialization of the bss section.
|
|
*/
|
|
|
|
#include <linux/processor.h>
|
|
#include <linux/string.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/lowcore.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/timex.h>
|
|
#include "entry.h"
|
|
|
|
static void __init reset_tod_clock(void)
|
|
{
|
|
u64 time;
|
|
|
|
if (store_tod_clock(&time) == 0)
|
|
return;
|
|
/* TOD clock not running. Set the clock to Unix Epoch. */
|
|
if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
|
|
disabled_wait(0);
|
|
|
|
memset(tod_clock_base, 0, 16);
|
|
*(__u64 *) &tod_clock_base[1] = TOD_UNIX_EPOCH;
|
|
S390_lowcore.last_update_clock = TOD_UNIX_EPOCH;
|
|
}
|
|
|
|
static void __init rescue_initrd(void)
|
|
{
|
|
unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
|
|
|
|
/*
|
|
* Just like in case of IPL from VM reader we make sure there is a
|
|
* gap of 4MB between end of kernel and start of initrd.
|
|
* That way we can also be sure that saving an NSS will succeed,
|
|
* which however only requires different segments.
|
|
*/
|
|
if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD))
|
|
return;
|
|
if (!INITRD_START || !INITRD_SIZE)
|
|
return;
|
|
if (INITRD_START >= min_initrd_addr)
|
|
return;
|
|
memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
|
|
INITRD_START = min_initrd_addr;
|
|
}
|
|
|
|
static void __init clear_bss_section(void)
|
|
{
|
|
memset(__bss_start, 0, __bss_stop - __bss_start);
|
|
}
|
|
|
|
void __init startup_init_nobss(void)
|
|
{
|
|
reset_tod_clock();
|
|
rescue_initrd();
|
|
clear_bss_section();
|
|
}
|