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linux/arch/s390/kernel/early.c
Hendrik Brueckner a0443fbb46 [S390] Extra Kernel Parameters via VMPARM
Now it is possible to specify additional kernel parameters on the IPL
command line using the IPL PARM option.
If the Linux system is already running, the new reipl sysfs attribute
'parm' can be used to change kernel parameters for the next reboot.
Examples:
  IPL    C PARM dasd=1234 root=/dev/dasda1
  IPL 1234 PARM savesys=mylnxnss
  echo "init=/bin/bash" > /sys/firmware/reipl/ccw/parm

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-14 10:02:14 +02:00

504 lines
11 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/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/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 void __init setup_boot_command_line(void);
#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 noinline __init void detect_machine_type(void)
{
struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
/* Running under z/VM ? */
if (cpuinfo->cpu_id.version == 0xff)
machine_flags |= MACHINE_FLAG_VM;
/* Running on a P/390 ? */
if (cpuinfo->cpu_id.machine == 0x7490)
machine_flags |= MACHINE_FLAG_P390;
/* Running under KVM ? */
if (cpuinfo->cpu_id.version == 0xfe)
machine_flags |= MACHINE_FLAG_KVM;
}
#ifdef CONFIG_64BIT
static noinline __init int memory_fast_detect(void)
{
unsigned long val0 = 0;
unsigned long val1 = 0xc;
int ret = -ENOSYS;
if (ipl_flags & IPL_NSS_VALID)
return -ENOSYS;
asm volatile(
" diag %1,%2,0x260\n"
"0: lhi %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (ret), "+d" (val0), "+d" (val1) : : "cc");
if (ret || val0 != val1)
return -ENOSYS;
memory_chunk[0].size = val0 + 1;
return 0;
}
#else
static inline int memory_fast_detect(void)
{
return -ENOSYS;
}
#endif
static inline __init unsigned long __tprot(unsigned long addr)
{
int cc = -1;
asm volatile(
" tprot 0(%1),0\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (cc) : "a" (addr) : "cc");
return (unsigned long)cc;
}
/* Checking memory in 128KB increments. */
#define CHUNK_INCR (1UL << 17)
#define ADDR2G (1UL << 31)
static noinline __init void find_memory_chunks(unsigned long memsize)
{
unsigned long addr = 0, old_addr = 0;
unsigned long old_cc = CHUNK_READ_WRITE;
unsigned long cc;
int chunk = 0;
while (chunk < MEMORY_CHUNKS) {
cc = __tprot(addr);
while (cc == old_cc) {
addr += CHUNK_INCR;
if (memsize && addr >= memsize)
break;
#ifndef CONFIG_64BIT
if (addr == ADDR2G)
break;
#endif
cc = __tprot(addr);
}
if (old_addr != addr &&
(old_cc == CHUNK_READ_WRITE || old_cc == CHUNK_READ_ONLY)) {
memory_chunk[chunk].addr = old_addr;
memory_chunk[chunk].size = addr - old_addr;
memory_chunk[chunk].type = old_cc;
chunk++;
}
old_addr = addr;
old_cc = cc;
#ifndef CONFIG_64BIT
if (addr == ADDR2G)
break;
#endif
/*
* Finish memory detection at the first hole
* if storage size is unknown.
*/
if (cc == -1UL && !memsize)
break;
if (memsize && addr >= memsize)
break;
}
}
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);
boot_command_line[ARCH_COMMAND_LINE_SIZE - 1] = 0;
/* 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)
{
unsigned long long memsize;
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_read_info_early();
sclp_facilities_detect();
memsize = sclp_memory_detect();
#ifndef CONFIG_64BIT
/*
* Can't deal with more than 2G in 31 bit addressing mode, so
* limit the value in order to avoid strange side effects.
*/
if (memsize > ADDR2G)
memsize = ADDR2G;
#endif
if (memory_fast_detect() < 0)
find_memory_chunks((unsigned long) memsize);
lockdep_on();
}