setup.c

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/*
 *  arch/s390/kernel/setup.c
 *
 *  S390 version
 *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Hartmut Penner ([e-mail]),
 *               Martin Schwidefsky ([e-mail])
 *
 *  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/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/malloc.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>
#ifdef CONFIG_BLK_DEV_RAM
#include <linux/blk.h>
#endif
#include <linux/bootmem.h>
#include <linux/console.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/smp.h>
#include <asm/mmu_context.h>

/*
 * Machine setup..
 */
__u16 boot_cpu_addr;
int cpus_initialized = 0;
unsigned long cpu_initialized = 0;

/*
 * Setup options
 */

#ifdef CONFIG_BLK_DEV_RAM
extern int rd_doload;                  /* 1 = load ramdisk, 0 = don't load */
extern int rd_prompt;           /* 1 = prompt for ramdisk, 0 = don't prompt*/
extern int rd_image_start;             /* starting block # of image        */
#endif

extern int root_mountflags;
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, };
       char saved_command_line[COMMAND_LINE_SIZE];

static struct resource code_resource = { "Kernel code", 0x100000, 0 };
static struct resource data_resource = { "Kernel data", 0, 0 };

/*
 * cpu_init() initializes state that is per-CPU.
 */
void __init cpu_init (void)
{
        int nr = smp_processor_id();

        if (test_and_set_bit(nr,&cpu_initialized)) {
                printk("CPU#%d ALREADY INITIALIZED!!!!!!!!!\n", nr);
                for (;;) __sti();
        }
        cpus_initialized++;

        /*
         * 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 = hard_smp_processor_id();
        S390_lowcore.cpu_data.cpu_nr = nr;

        /*
         * Force FPU initialization:
         */
        current->flags &= ~PF_USEDFPU;
        current->used_math = 0;

        /* Setup active_mm for idle_task  */
        atomic_inc(&init_mm.mm_count);
        current->active_mm = &init_mm;
        if (current->mm)
                BUG();
        enter_lazy_tlb(&init_mm, current, nr);
}

/*
 * 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);

/*
 * Reboot, halt and power_off routines for non SMP.
 */

#ifndef CONFIG_SMP
void machine_restart(char * __unused)
{
	reipl(S390_lowcore.ipl_device);
}

void machine_halt(void)
{
        if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
                cpcmd(vmhalt_cmd, NULL, 0);
        disabled_wait(0);
}

void machine_power_off(void)
{
        if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
                cpcmd(vmpoff_cmd, NULL, 0);
        disabled_wait(0);
}
#endif

/*
 * Waits for 'delay' microseconds using the tod clock
 */
void tod_wait(unsigned long delay)
{
        uint64_t start_cc, end_cc;

	if (delay == 0)
		return;
        asm volatile ("STCK %0" : "=m" (start_cc));
	do {
		asm volatile ("STCK %0" : "=m" (end_cc));
	} while (((end_cc - start_cc)/4096) < delay);
}

/*
 * Setup function called from init/main.c just after the banner
 * was printed.
 */
void __init setup_arch(char **cmdline_p)
{
        unsigned long bootmap_size;
        unsigned long memory_start, memory_end;
        char c = ' ', *to = command_line, *from = COMMAND_LINE;
	struct resource *res;
	unsigned long start_pfn, end_pfn;
        static unsigned int smptrap=0;
        unsigned long delay = 0;
        int len = 0;

        if (smptrap)
                return;
        smptrap=1;

        printk("Command line is: %s\n", COMMAND_LINE);

        /*
         * Setup lowcore information for boot cpu
         */
        cpu_init();
        boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;

        /*
         * print what head.S has found out about the machine 
         */
	printk((MACHINE_IS_VM) ?
	       "We are running under VM\n" :
	       "We are running native\n");
	printk((MACHINE_HAS_IEEE) ?
	       "This machine has an IEEE fpu\n" :
	       "This machine has no IEEE fpu\n");

        ROOT_DEV = to_kdev_t(ORIG_ROOT_DEV);
#ifdef CONFIG_BLK_DEV_RAM
        rd_image_start = RAMDISK_FLAGS & RAMDISK_IMAGE_START_MASK;
        rd_prompt = ((RAMDISK_FLAGS & RAMDISK_PROMPT_FLAG) != 0);
        rd_doload = ((RAMDISK_FLAGS & RAMDISK_LOAD_FLAG) != 0);
#endif
	/* nasty stuff with PARMAREAs. we use head.S or parameterline
	  if (!MOUNT_ROOT_RDONLY)
	  root_mountflags &= ~MS_RDONLY;
	*/
        memory_start = (unsigned long) &_end;    /* fixit if use $CODELO etc*/
	memory_end = MEMORY_SIZE;                /* detected in head.s */
        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;

	code_resource.start = (unsigned long) &_text;
	code_resource.end = (unsigned long) &_etext - 1;
	data_resource.start = (unsigned long) &_etext;
	data_resource.end = (unsigned long) &_edata - 1;

        /* 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) {
                        if (to != command_line) to--;
                        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) {
			if (to != command_line) to--;
                        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 requestion amount of time */
			tod_wait(delay);
                }
                c = *(from++);
                if (!c)
                        break;
                if (COMMAND_LINE_SIZE <= ++len)
                        break;
                *(to++) = c;
        }
        *to = '\0';
        *cmdline_p = command_line;

	/*
	 * partially used pages are not usable - thus
	 * we are rounding upwards:
	 */
	start_pfn = (__pa(&_end) + PAGE_SIZE - 1) >> PAGE_SHIFT;
	end_pfn = memory_end >> PAGE_SHIFT;

	/*
	 * Initialize the boot-time allocator (with low memory only):
	 */
	bootmap_size = init_bootmem(start_pfn, end_pfn);

	/*
	 * Register RAM pages with the bootmem allocator.
	 */
	free_bootmem(start_pfn << PAGE_SHIFT, 
		     (end_pfn - start_pfn) << PAGE_SHIFT);

        /*
         * 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);

        paging_init();
#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
	res = alloc_bootmem_low(sizeof(struct resource));
	res->start = 0;
	res->end = memory_end;
	res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
	request_resource(&iomem_resource, res);
	request_resource(res, &code_resource);
	request_resource(res, &data_resource);
}

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);
}

/*
 *	Get CPU information for use by the procfs.
 */

int get_cpuinfo(char * buffer)
{
        struct cpuinfo_S390 *cpuinfo;
        char *p = buffer;
        int i;

        p += sprintf(p,"vendor_id       : IBM/S390\n"
                       "# processors    : %i\n"
                       "bogomips per cpu: %lu.%02lu\n",
                       smp_num_cpus, loops_per_sec/500000,
                       (loops_per_sec/5000)%100);
        for (i = 0; i < smp_num_cpus; i++) {
                cpuinfo = &safe_get_cpu_lowcore(i).cpu_data;
                p += sprintf(p,"processor %i: "
                               "version = %02X,  "
                               "identification = %06X,  "
                               "machine = %04X\n",
                               i, cpuinfo->cpu_id.version,
                               cpuinfo->cpu_id.ident,
                               cpuinfo->cpu_id.machine);
        }
        return p - buffer;
}