From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- arch/s390/kernel/early_nobss.c | 65 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 arch/s390/kernel/early_nobss.c (limited to 'arch/s390/kernel/early_nobss.c') diff --git a/arch/s390/kernel/early_nobss.c b/arch/s390/kernel/early_nobss.c new file mode 100644 index 000000000..2d84fc48d --- /dev/null +++ b/arch/s390/kernel/early_nobss.c @@ -0,0 +1,65 @@ +// 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 +#include +#include +#include +#include +#include +#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(); +} -- cgit v1.2.3