linux/arch/s390/kernel/setup.c
Martin Schwidefsky 951f22d5b1 [PATCH] s390: spin lock retry
Split spin lock and r/w lock implementation into a single try which is done
inline and an out of line function that repeatedly tries to get the lock
before doing the cpu_relax().  Add a system control to set the number of
retries before a cpu is yielded.

The reason for the spin lock retry is that the diagnose 0x44 that is used to
give up the virtual cpu is quite expensive.  For spin locks that are held only
for a short period of time the costs of the diagnoses outweights the savings
for spin locks that are held for a longer timer.  The default retry count is
1000.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:04 -07:00

683 lines
17 KiB
C

/*
* arch/s390/kernel/setup.c
*
* S390 version
* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*
* Derived from "arch/i386/kernel/setup.c"
* Copyright (C) 1995, Linus Torvalds
*/
/*
* This file handles the architecture-dependent parts of initialization
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/config.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/bootmem.h>
#include <linux/root_dev.h>
#include <linux/console.h>
#include <linux/seq_file.h>
#include <linux/kernel_stat.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/smp.h>
#include <asm/mmu_context.h>
#include <asm/cpcmd.h>
#include <asm/lowcore.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/ptrace.h>
/*
* Machine setup..
*/
unsigned int console_mode = 0;
unsigned int console_devno = -1;
unsigned int console_irq = -1;
unsigned long memory_size = 0;
unsigned long machine_flags = 0;
struct {
unsigned long addr, size, type;
} memory_chunk[MEMORY_CHUNKS] = { { 0 } };
#define CHUNK_READ_WRITE 0
#define CHUNK_READ_ONLY 1
volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
unsigned long __initdata zholes_size[MAX_NR_ZONES];
static unsigned long __initdata memory_end;
/*
* Setup options
*/
extern int _text,_etext, _edata, _end;
/*
* This is set up by the setup-routine at boot-time
* for S390 need to find out, what we have to setup
* using address 0x10400 ...
*/
#include <asm/setup.h>
static char command_line[COMMAND_LINE_SIZE] = { 0, };
static struct resource code_resource = {
.name = "Kernel code",
.start = (unsigned long) &_text,
.end = (unsigned long) &_etext - 1,
.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
};
static struct resource data_resource = {
.name = "Kernel data",
.start = (unsigned long) &_etext,
.end = (unsigned long) &_edata - 1,
.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
};
/*
* cpu_init() initializes state that is per-CPU.
*/
void __devinit cpu_init (void)
{
int addr = hard_smp_processor_id();
/*
* Store processor id in lowcore (used e.g. in timer_interrupt)
*/
asm volatile ("stidp %0": "=m" (S390_lowcore.cpu_data.cpu_id));
S390_lowcore.cpu_data.cpu_addr = addr;
/*
* Force FPU initialization:
*/
clear_thread_flag(TIF_USEDFPU);
clear_used_math();
atomic_inc(&init_mm.mm_count);
current->active_mm = &init_mm;
if (current->mm)
BUG();
enter_lazy_tlb(&init_mm, current);
}
/*
* VM halt and poweroff setup routines
*/
char vmhalt_cmd[128] = "";
char vmpoff_cmd[128] = "";
static inline void strncpy_skip_quote(char *dst, char *src, int n)
{
int sx, dx;
dx = 0;
for (sx = 0; src[sx] != 0; sx++) {
if (src[sx] == '"') continue;
dst[dx++] = src[sx];
if (dx >= n) break;
}
}
static int __init vmhalt_setup(char *str)
{
strncpy_skip_quote(vmhalt_cmd, str, 127);
vmhalt_cmd[127] = 0;
return 1;
}
__setup("vmhalt=", vmhalt_setup);
static int __init vmpoff_setup(char *str)
{
strncpy_skip_quote(vmpoff_cmd, str, 127);
vmpoff_cmd[127] = 0;
return 1;
}
__setup("vmpoff=", vmpoff_setup);
/*
* condev= and conmode= setup parameter.
*/
static int __init condev_setup(char *str)
{
int vdev;
vdev = simple_strtoul(str, &str, 0);
if (vdev >= 0 && vdev < 65536) {
console_devno = vdev;
console_irq = -1;
}
return 1;
}
__setup("condev=", condev_setup);
static int __init conmode_setup(char *str)
{
#if defined(CONFIG_SCLP_CONSOLE)
if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
SET_CONSOLE_SCLP;
#endif
#if defined(CONFIG_TN3215_CONSOLE)
if (strncmp(str, "3215", 5) == 0)
SET_CONSOLE_3215;
#endif
#if defined(CONFIG_TN3270_CONSOLE)
if (strncmp(str, "3270", 5) == 0)
SET_CONSOLE_3270;
#endif
return 1;
}
__setup("conmode=", conmode_setup);
static void __init conmode_default(void)
{
char query_buffer[1024];
char *ptr;
if (MACHINE_IS_VM) {
__cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
ptr = strstr(query_buffer, "SUBCHANNEL =");
console_irq = simple_strtoul(ptr + 13, NULL, 16);
__cpcmd("QUERY TERM", query_buffer, 1024, NULL);
ptr = strstr(query_buffer, "CONMODE");
/*
* Set the conmode to 3215 so that the device recognition
* will set the cu_type of the console to 3215. If the
* conmode is 3270 and we don't set it back then both
* 3215 and the 3270 driver will try to access the console
* device (3215 as console and 3270 as normal tty).
*/
__cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
if (ptr == NULL) {
#if defined(CONFIG_SCLP_CONSOLE)
SET_CONSOLE_SCLP;
#endif
return;
}
if (strncmp(ptr + 8, "3270", 4) == 0) {
#if defined(CONFIG_TN3270_CONSOLE)
SET_CONSOLE_3270;
#elif defined(CONFIG_TN3215_CONSOLE)
SET_CONSOLE_3215;
#elif defined(CONFIG_SCLP_CONSOLE)
SET_CONSOLE_SCLP;
#endif
} else if (strncmp(ptr + 8, "3215", 4) == 0) {
#if defined(CONFIG_TN3215_CONSOLE)
SET_CONSOLE_3215;
#elif defined(CONFIG_TN3270_CONSOLE)
SET_CONSOLE_3270;
#elif defined(CONFIG_SCLP_CONSOLE)
SET_CONSOLE_SCLP;
#endif
}
} else if (MACHINE_IS_P390) {
#if defined(CONFIG_TN3215_CONSOLE)
SET_CONSOLE_3215;
#elif defined(CONFIG_TN3270_CONSOLE)
SET_CONSOLE_3270;
#endif
} else {
#if defined(CONFIG_SCLP_CONSOLE)
SET_CONSOLE_SCLP;
#endif
}
}
#ifdef CONFIG_SMP
extern void machine_restart_smp(char *);
extern void machine_halt_smp(void);
extern void machine_power_off_smp(void);
void (*_machine_restart)(char *command) = machine_restart_smp;
void (*_machine_halt)(void) = machine_halt_smp;
void (*_machine_power_off)(void) = machine_power_off_smp;
#else
/*
* Reboot, halt and power_off routines for non SMP.
*/
extern void reipl(unsigned long devno);
static void do_machine_restart_nonsmp(char * __unused)
{
if (MACHINE_IS_VM)
cpcmd ("IPL", NULL, 0);
else
reipl (0x10000 | S390_lowcore.ipl_device);
}
static void do_machine_halt_nonsmp(void)
{
if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
cpcmd(vmhalt_cmd, NULL, 0);
signal_processor(smp_processor_id(), sigp_stop_and_store_status);
}
static void do_machine_power_off_nonsmp(void)
{
if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
cpcmd(vmpoff_cmd, NULL, 0);
signal_processor(smp_processor_id(), sigp_stop_and_store_status);
}
void (*_machine_restart)(char *command) = do_machine_restart_nonsmp;
void (*_machine_halt)(void) = do_machine_halt_nonsmp;
void (*_machine_power_off)(void) = do_machine_power_off_nonsmp;
#endif
/*
* Reboot, halt and power_off stubs. They just call _machine_restart,
* _machine_halt or _machine_power_off.
*/
void machine_restart(char *command)
{
console_unblank();
_machine_restart(command);
}
void machine_halt(void)
{
console_unblank();
_machine_halt();
}
void machine_power_off(void)
{
console_unblank();
_machine_power_off();
}
static void __init
add_memory_hole(unsigned long start, unsigned long end)
{
unsigned long dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT;
if (end <= dma_pfn)
zholes_size[ZONE_DMA] += end - start + 1;
else if (start > dma_pfn)
zholes_size[ZONE_NORMAL] += end - start + 1;
else {
zholes_size[ZONE_DMA] += dma_pfn - start + 1;
zholes_size[ZONE_NORMAL] += end - dma_pfn;
}
}
static void __init
parse_cmdline_early(char **cmdline_p)
{
char c = ' ', cn, *to = command_line, *from = COMMAND_LINE;
unsigned long delay = 0;
/* Save unparsed command line copy for /proc/cmdline */
memcpy(saved_command_line, COMMAND_LINE, COMMAND_LINE_SIZE);
saved_command_line[COMMAND_LINE_SIZE-1] = '\0';
for (;;) {
/*
* "mem=XXX[kKmM]" sets memsize
*/
if (c == ' ' && strncmp(from, "mem=", 4) == 0) {
memory_end = simple_strtoul(from+4, &from, 0);
if ( *from == 'K' || *from == 'k' ) {
memory_end = memory_end << 10;
from++;
} else if ( *from == 'M' || *from == 'm' ) {
memory_end = memory_end << 20;
from++;
}
}
/*
* "ipldelay=XXX[sm]" sets ipl delay in seconds or minutes
*/
if (c == ' ' && strncmp(from, "ipldelay=", 9) == 0) {
delay = simple_strtoul(from+9, &from, 0);
if (*from == 's' || *from == 'S') {
delay = delay*1000000;
from++;
} else if (*from == 'm' || *from == 'M') {
delay = delay*60*1000000;
from++;
}
/* now wait for the requested amount of time */
udelay(delay);
}
cn = *(from++);
if (!cn)
break;
if (cn == '\n')
cn = ' '; /* replace newlines with space */
if (cn == 0x0d)
cn = ' '; /* replace 0x0d with space */
if (cn == ' ' && c == ' ')
continue; /* remove additional spaces */
c = cn;
if (to - command_line >= COMMAND_LINE_SIZE)
break;
*(to++) = c;
}
if (c == ' ' && to > command_line) to--;
*to = '\0';
*cmdline_p = command_line;
}
static void __init
setup_lowcore(void)
{
struct _lowcore *lc;
int lc_pages;
/*
* Setup lowcore for boot cpu
*/
lc_pages = sizeof(void *) == 8 ? 2 : 1;
lc = (struct _lowcore *)
__alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
memset(lc, 0, lc_pages * PAGE_SIZE);
lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
lc->restart_psw.addr =
PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
lc->external_new_psw.mask = PSW_KERNEL_BITS;
lc->external_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
lc->svc_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
lc->program_new_psw.mask = PSW_KERNEL_BITS;
lc->program_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
lc->mcck_new_psw.mask =
PSW_KERNEL_BITS & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
lc->mcck_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
lc->io_new_psw.mask = PSW_KERNEL_BITS;
lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
lc->ipl_device = S390_lowcore.ipl_device;
lc->jiffy_timer = -1LL;
lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
lc->async_stack = (unsigned long)
__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
lc->panic_stack = (unsigned long)
__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
lc->current_task = (unsigned long) init_thread_union.thread_info.task;
lc->thread_info = (unsigned long) &init_thread_union;
#ifndef CONFIG_ARCH_S390X
if (MACHINE_HAS_IEEE) {
lc->extended_save_area_addr = (__u32)
__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
/* enable extended save area */
ctl_set_bit(14, 29);
}
#endif
set_prefix((u32)(unsigned long) lc);
}
static void __init
setup_resources(void)
{
struct resource *res;
int i;
for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
res = alloc_bootmem_low(sizeof(struct resource));
res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
switch (memory_chunk[i].type) {
case CHUNK_READ_WRITE:
res->name = "System RAM";
break;
case CHUNK_READ_ONLY:
res->name = "System ROM";
res->flags |= IORESOURCE_READONLY;
break;
default:
res->name = "reserved";
}
res->start = memory_chunk[i].addr;
res->end = memory_chunk[i].addr + memory_chunk[i].size - 1;
request_resource(&iomem_resource, res);
request_resource(res, &code_resource);
request_resource(res, &data_resource);
}
}
static void __init
setup_memory(void)
{
unsigned long bootmap_size;
unsigned long start_pfn, end_pfn, init_pfn;
unsigned long last_rw_end;
int i;
/*
* partially used pages are not usable - thus
* we are rounding upwards:
*/
start_pfn = (__pa(&_end) + PAGE_SIZE - 1) >> PAGE_SHIFT;
end_pfn = max_pfn = memory_end >> PAGE_SHIFT;
/* Initialize storage key for kernel pages */
for (init_pfn = 0 ; init_pfn < start_pfn; init_pfn++)
page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
/*
* Initialize the boot-time allocator (with low memory only):
*/
bootmap_size = init_bootmem(start_pfn, end_pfn);
/*
* Register RAM areas with the bootmem allocator.
*/
last_rw_end = start_pfn;
for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
unsigned long start_chunk, end_chunk;
if (memory_chunk[i].type != CHUNK_READ_WRITE)
continue;
start_chunk = (memory_chunk[i].addr + PAGE_SIZE - 1);
start_chunk >>= PAGE_SHIFT;
end_chunk = (memory_chunk[i].addr + memory_chunk[i].size);
end_chunk >>= PAGE_SHIFT;
if (start_chunk < start_pfn)
start_chunk = start_pfn;
if (end_chunk > end_pfn)
end_chunk = end_pfn;
if (start_chunk < end_chunk) {
/* Initialize storage key for RAM pages */
for (init_pfn = start_chunk ; init_pfn < end_chunk;
init_pfn++)
page_set_storage_key(init_pfn << PAGE_SHIFT,
PAGE_DEFAULT_KEY);
free_bootmem(start_chunk << PAGE_SHIFT,
(end_chunk - start_chunk) << PAGE_SHIFT);
if (last_rw_end < start_chunk)
add_memory_hole(last_rw_end, start_chunk - 1);
last_rw_end = end_chunk;
}
}
psw_set_key(PAGE_DEFAULT_KEY);
if (last_rw_end < end_pfn - 1)
add_memory_hole(last_rw_end, end_pfn - 1);
/*
* Reserve the bootmem bitmap itself as well. We do this in two
* steps (first step was init_bootmem()) because this catches
* the (very unlikely) case of us accidentally initializing the
* bootmem allocator with an invalid RAM area.
*/
reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size);
#ifdef CONFIG_BLK_DEV_INITRD
if (INITRD_START) {
if (INITRD_START + INITRD_SIZE <= memory_end) {
reserve_bootmem(INITRD_START, INITRD_SIZE);
initrd_start = INITRD_START;
initrd_end = initrd_start + INITRD_SIZE;
} else {
printk("initrd extends beyond end of memory "
"(0x%08lx > 0x%08lx)\ndisabling initrd\n",
initrd_start + INITRD_SIZE, memory_end);
initrd_start = initrd_end = 0;
}
}
#endif
}
/*
* Setup function called from init/main.c just after the banner
* was printed.
*/
void __init
setup_arch(char **cmdline_p)
{
/*
* print what head.S has found out about the machine
*/
#ifndef CONFIG_ARCH_S390X
printk((MACHINE_IS_VM) ?
"We are running under VM (31 bit mode)\n" :
"We are running native (31 bit mode)\n");
printk((MACHINE_HAS_IEEE) ?
"This machine has an IEEE fpu\n" :
"This machine has no IEEE fpu\n");
#else /* CONFIG_ARCH_S390X */
printk((MACHINE_IS_VM) ?
"We are running under VM (64 bit mode)\n" :
"We are running native (64 bit mode)\n");
#endif /* CONFIG_ARCH_S390X */
ROOT_DEV = Root_RAM0;
#ifndef CONFIG_ARCH_S390X
memory_end = memory_size & ~0x400000UL; /* align memory end to 4MB */
/*
* We need some free virtual space to be able to do vmalloc.
* On a machine with 2GB memory we make sure that we have at
* least 128 MB free space for vmalloc.
*/
if (memory_end > 1920*1024*1024)
memory_end = 1920*1024*1024;
#else /* CONFIG_ARCH_S390X */
memory_end = memory_size & ~0x200000UL; /* detected in head.s */
#endif /* CONFIG_ARCH_S390X */
init_mm.start_code = PAGE_OFFSET;
init_mm.end_code = (unsigned long) &_etext;
init_mm.end_data = (unsigned long) &_edata;
init_mm.brk = (unsigned long) &_end;
parse_cmdline_early(cmdline_p);
setup_memory();
setup_resources();
setup_lowcore();
cpu_init();
__cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
/*
* Create kernel page tables and switch to virtual addressing.
*/
paging_init();
/* Setup default console */
conmode_default();
}
void print_cpu_info(struct cpuinfo_S390 *cpuinfo)
{
printk("cpu %d "
#ifdef CONFIG_SMP
"phys_idx=%d "
#endif
"vers=%02X ident=%06X machine=%04X unused=%04X\n",
cpuinfo->cpu_nr,
#ifdef CONFIG_SMP
cpuinfo->cpu_addr,
#endif
cpuinfo->cpu_id.version,
cpuinfo->cpu_id.ident,
cpuinfo->cpu_id.machine,
cpuinfo->cpu_id.unused);
}
/*
* show_cpuinfo - Get information on one CPU for use by procfs.
*/
static int show_cpuinfo(struct seq_file *m, void *v)
{
struct cpuinfo_S390 *cpuinfo;
unsigned long n = (unsigned long) v - 1;
if (!n) {
seq_printf(m, "vendor_id : IBM/S390\n"
"# processors : %i\n"
"bogomips per cpu: %lu.%02lu\n",
num_online_cpus(), loops_per_jiffy/(500000/HZ),
(loops_per_jiffy/(5000/HZ))%100);
}
if (cpu_online(n)) {
#ifdef CONFIG_SMP
if (smp_processor_id() == n)
cpuinfo = &S390_lowcore.cpu_data;
else
cpuinfo = &lowcore_ptr[n]->cpu_data;
#else
cpuinfo = &S390_lowcore.cpu_data;
#endif
seq_printf(m, "processor %li: "
"version = %02X, "
"identification = %06X, "
"machine = %04X\n",
n, cpuinfo->cpu_id.version,
cpuinfo->cpu_id.ident,
cpuinfo->cpu_id.machine);
}
return 0;
}
static void *c_start(struct seq_file *m, loff_t *pos)
{
return *pos < NR_CPUS ? (void *)((unsigned long) *pos + 1) : NULL;
}
static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return c_start(m, pos);
}
static void c_stop(struct seq_file *m, void *v)
{
}
struct seq_operations cpuinfo_op = {
.start = c_start,
.next = c_next,
.stop = c_stop,
.show = show_cpuinfo,
};