linux/arch/s390/kernel/early.c
Martin Schwidefsky b6112ccbff [S390] add read_persistent_clock
Add a read_persistent_clock function that does not just return 0.
Since timekeeping_init calls the function before time_init has been
called move reset_tod_clock to early.c to make sure that the TOD
clock is running when read_persistent_clock is invoked.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-04-14 15:37:27 +02:00

415 lines
9.1 KiB
C

/*
* arch/s390/kernel/early.c
*
* Copyright IBM Corp. 2007
* Author(s): Hongjie Yang <hongjie@us.ibm.com>,
* Heiko Carstens <heiko.carstens@de.ibm.com>
*/
#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/lockdep.h>
#include <linux/module.h>
#include <linux/pfn.h>
#include <linux/uaccess.h>
#include <asm/ebcdic.h>
#include <asm/ipl.h>
#include <asm/lowcore.h>
#include <asm/processor.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/sysinfo.h>
#include <asm/cpcmd.h>
#include <asm/sclp.h>
#include "entry.h"
/*
* Create a Kernel NSS if the SAVESYS= parameter is defined
*/
#define DEFSYS_CMD_SIZE 128
#define SAVESYS_CMD_SIZE 32
char kernel_nss_name[NSS_NAME_SIZE + 1];
static unsigned long machine_flags;
static void __init setup_boot_command_line(void);
/*
* Get the TOD clock running.
*/
static void __init reset_tod_clock(void)
{
u64 time;
if (store_clock(&time) == 0)
return;
/* TOD clock not running. Set the clock to Unix Epoch. */
if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0)
disabled_wait(0);
sched_clock_base_cc = TOD_UNIX_EPOCH;
}
#ifdef CONFIG_SHARED_KERNEL
int __init savesys_ipl_nss(char *cmd, const int cmdlen);
asm(
" .section .init.text,\"ax\",@progbits\n"
" .align 4\n"
" .type savesys_ipl_nss, @function\n"
"savesys_ipl_nss:\n"
#ifdef CONFIG_64BIT
" stmg 6,15,48(15)\n"
" lgr 14,3\n"
" sam31\n"
" diag 2,14,0x8\n"
" sam64\n"
" lgr 2,14\n"
" lmg 6,15,48(15)\n"
#else
" stm 6,15,24(15)\n"
" lr 14,3\n"
" diag 2,14,0x8\n"
" lr 2,14\n"
" lm 6,15,24(15)\n"
#endif
" br 14\n"
" .size savesys_ipl_nss, .-savesys_ipl_nss\n");
static noinline __init void create_kernel_nss(void)
{
unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
#ifdef CONFIG_BLK_DEV_INITRD
unsigned int sinitrd_pfn, einitrd_pfn;
#endif
int response;
size_t len;
char *savesys_ptr;
char upper_command_line[COMMAND_LINE_SIZE];
char defsys_cmd[DEFSYS_CMD_SIZE];
char savesys_cmd[SAVESYS_CMD_SIZE];
/* Do nothing if we are not running under VM */
if (!MACHINE_IS_VM)
return;
/* Convert COMMAND_LINE to upper case */
for (i = 0; i < strlen(boot_command_line); i++)
upper_command_line[i] = toupper(boot_command_line[i]);
savesys_ptr = strstr(upper_command_line, "SAVESYS=");
if (!savesys_ptr)
return;
savesys_ptr += 8; /* Point to the beginning of the NSS name */
for (i = 0; i < NSS_NAME_SIZE; i++) {
if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
break;
kernel_nss_name[i] = savesys_ptr[i];
}
stext_pfn = PFN_DOWN(__pa(&_stext));
eshared_pfn = PFN_DOWN(__pa(&_eshared));
end_pfn = PFN_UP(__pa(&_end));
min_size = end_pfn << 2;
sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
eshared_pfn, end_pfn);
#ifdef CONFIG_BLK_DEV_INITRD
if (INITRD_START && INITRD_SIZE) {
sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
min_size = einitrd_pfn << 2;
sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
sinitrd_pfn, einitrd_pfn);
}
#endif
sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
defsys_cmd, min_size);
sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
kernel_nss_name, kernel_nss_name);
__cpcmd(defsys_cmd, NULL, 0, &response);
if (response != 0) {
kernel_nss_name[0] = '\0';
return;
}
len = strlen(savesys_cmd);
ASCEBC(savesys_cmd, len);
response = savesys_ipl_nss(savesys_cmd, len);
/* On success: response is equal to the command size,
* max SAVESYS_CMD_SIZE
* On error: response contains the numeric portion of cp error message.
* for SAVESYS it will be >= 263
*/
if (response > SAVESYS_CMD_SIZE) {
kernel_nss_name[0] = '\0';
return;
}
/* re-setup boot command line with new ipl vm parms */
ipl_update_parameters();
setup_boot_command_line();
ipl_flags = IPL_NSS_VALID;
}
#else /* CONFIG_SHARED_KERNEL */
static inline void create_kernel_nss(void) { }
#endif /* CONFIG_SHARED_KERNEL */
/*
* Clear bss memory
*/
static noinline __init void clear_bss_section(void)
{
memset(__bss_start, 0, __bss_stop - __bss_start);
}
/*
* Initialize storage key for kernel pages
*/
static noinline __init void init_kernel_storage_key(void)
{
unsigned long end_pfn, init_pfn;
end_pfn = PFN_UP(__pa(&_end));
for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
}
static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
static noinline __init void detect_machine_type(void)
{
/* No VM information? Looks like LPAR */
if (stsi(&vmms, 3, 2, 2) == -ENOSYS)
return;
if (!vmms.count)
return;
/* Running under KVM? If not we assume z/VM */
if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
machine_flags |= MACHINE_FLAG_KVM;
else
machine_flags |= MACHINE_FLAG_VM;
}
static __init void early_pgm_check_handler(void)
{
unsigned long addr;
const struct exception_table_entry *fixup;
addr = S390_lowcore.program_old_psw.addr;
fixup = search_exception_tables(addr & PSW_ADDR_INSN);
if (!fixup)
disabled_wait(0);
S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
}
static noinline __init void setup_lowcore_early(void)
{
psw_t psw;
psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
S390_lowcore.external_new_psw = psw;
psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
S390_lowcore.program_new_psw = psw;
s390_base_pgm_handler_fn = early_pgm_check_handler;
}
static noinline __init void setup_hpage(void)
{
#ifndef CONFIG_DEBUG_PAGEALLOC
unsigned int facilities;
facilities = stfl();
if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
return;
machine_flags |= MACHINE_FLAG_HPAGE;
__ctl_set_bit(0, 23);
#endif
}
static __init void detect_mvpg(void)
{
#ifndef CONFIG_64BIT
int rc;
asm volatile(
" la 0,0\n"
" mvpg %2,%2\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
if (!rc)
machine_flags |= MACHINE_FLAG_MVPG;
#endif
}
static __init void detect_ieee(void)
{
#ifndef CONFIG_64BIT
int rc, tmp;
asm volatile(
" efpc %1,0\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
if (!rc)
machine_flags |= MACHINE_FLAG_IEEE;
#endif
}
static __init void detect_csp(void)
{
#ifndef CONFIG_64BIT
int rc;
asm volatile(
" la 0,0\n"
" la 1,0\n"
" la 2,4\n"
" csp 0,2\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
if (!rc)
machine_flags |= MACHINE_FLAG_CSP;
#endif
}
static __init void detect_diag9c(void)
{
unsigned int cpu_address;
int rc;
cpu_address = stap();
asm volatile(
" diag %2,0,0x9c\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
if (!rc)
machine_flags |= MACHINE_FLAG_DIAG9C;
}
static __init void detect_diag44(void)
{
#ifdef CONFIG_64BIT
int rc;
asm volatile(
" diag 0,0,0x44\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
if (!rc)
machine_flags |= MACHINE_FLAG_DIAG44;
#endif
}
static __init void detect_machine_facilities(void)
{
#ifdef CONFIG_64BIT
unsigned int facilities;
facilities = stfl();
if (facilities & (1 << 28))
machine_flags |= MACHINE_FLAG_IDTE;
if (facilities & (1 << 23))
machine_flags |= MACHINE_FLAG_PFMF;
if (facilities & (1 << 4))
machine_flags |= MACHINE_FLAG_MVCOS;
#endif
}
static __init void rescue_initrd(void)
{
#ifdef CONFIG_BLK_DEV_INITRD
/*
* Move the initrd right behind the bss section in case it starts
* within the bss section. So we don't overwrite it when the bss
* section gets cleared.
*/
if (!INITRD_START || !INITRD_SIZE)
return;
if (INITRD_START >= (unsigned long) __bss_stop)
return;
memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
INITRD_START = (unsigned long) __bss_stop;
#endif
}
/* Set up boot command line */
static void __init setup_boot_command_line(void)
{
char *parm = NULL;
/* copy arch command line */
strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
/* append IPL PARM data to the boot command line */
if (MACHINE_IS_VM) {
parm = boot_command_line + strlen(boot_command_line);
*parm++ = ' ';
get_ipl_vmparm(parm);
if (parm[0] == '=')
memmove(boot_command_line, parm + 1, strlen(parm));
}
}
/*
* Save ipl parameters, clear bss memory, initialize storage keys
* and create a kernel NSS at startup if the SAVESYS= parm is defined
*/
void __init startup_init(void)
{
reset_tod_clock();
ipl_save_parameters();
rescue_initrd();
clear_bss_section();
init_kernel_storage_key();
lockdep_init();
lockdep_off();
sort_main_extable();
setup_lowcore_early();
detect_machine_type();
ipl_update_parameters();
setup_boot_command_line();
create_kernel_nss();
detect_mvpg();
detect_ieee();
detect_csp();
detect_diag9c();
detect_diag44();
detect_machine_facilities();
setup_hpage();
sclp_facilities_detect();
detect_memory_layout(memory_chunk);
S390_lowcore.machine_flags = machine_flags;
lockdep_on();
}