/*
 *  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>

/*
 * 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 */

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

/*
 * 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);
        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);
}

/*
 * 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);
                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);
                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);
                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);
}

EXPORT_SYMBOL(machine_restart);

void machine_halt(void)
{
        console_unblank();
        _machine_halt();
}

EXPORT_SYMBOL(machine_halt);

void machine_power_off(void)
{
        console_unblank();
        _machine_power_off();
}

EXPORT_SYMBOL(machine_power_off);

/*
 * Setup function called from init/main.c just after the banner
 * was printed.
 */
extern char _pstart, _pend, _stext;

void __init setup_arch(char **cmdline_p)
{
        unsigned long bootmap_size;
        unsigned long memory_start, memory_end;
        char c = ' ', cn, *to = command_line, *from = COMMAND_LINE;
        struct resource *res;
        unsigned long start_pfn, end_pfn;
        static unsigned int smptrap=0;
        unsigned long delay = 0;
        struct _lowcore *lc;
        int i;

        if (smptrap)
                return;
        smptrap=1;

        /*
         * 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;
        memory_start = (unsigned long) &_end;    /* fixit if use $CODELO etc*/
#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;

        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) {
                        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;

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

        /*
         * Register RAM areas with the bootmem allocator.
         */
        for (i = 0; i < 16 && 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)
                        free_bootmem(start_chunk << PAGE_SHIFT,
                                     (end_chunk - start_chunk) << 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);

#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 lowcore for boot cpu
         */
#ifndef CONFIG_ARCH_S390X
        lc = (struct _lowcore *) __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
        memset(lc, 0, PAGE_SIZE);
#else /* CONFIG_ARCH_S390X */
        lc = (struct _lowcore *) __alloc_bootmem(2*PAGE_SIZE, 2*PAGE_SIZE, 0);
        memset(lc, 0, 2*PAGE_SIZE);
#endif /* CONFIG_ARCH_S390X */
        lc->restart_psw.mask = PSW_BASE_BITS;
        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;
        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->current_task = (unsigned long) init_thread_union.thread_info.task;
        lc->thread_info = (unsigned long) &init_thread_union;
#ifdef CONFIG_ARCH_S390X
        if (MACHINE_HAS_DIAG44)
                lc->diag44_opcode = 0x83000044;
        else
                lc->diag44_opcode = 0x07000700;
#endif /* CONFIG_ARCH_S390X */
        set_prefix((u32)(unsigned long) lc);
        cpu_init();
        __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;

        /*
         * Create kernel page tables and switch to virtual addressing.
         */
        paging_init();

        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);

        /* 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,
};

/*
 * show_interrupts is needed by /proc/interrupts.
 */

static const char *intrclass_names[] = {
        "EXT",
        "I/O",
};

int show_interrupts(struct seq_file *p, void *v)
{
        int i = *(loff_t *) v, j;
        
        if (i == 0) {
                seq_puts(p, "           ");
                for (j=0; j<NR_CPUS; j++)
                        if (cpu_online(j))
                                seq_printf(p, "CPU%d       ",j);
                seq_putc(p, '\n');
        }
        
        if (i < NR_IRQS) {
                seq_printf(p, "%s: ", intrclass_names[i]);
#ifndef CONFIG_SMP
                seq_printf(p, "%10u ", kstat_irqs(i));
#else
                for (j = 0; j < NR_CPUS; j++)
                        if (cpu_online(j))
                                seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
                seq_putc(p, '\n');
                
        }
        
        return 0;
}

/*
 * For compatibilty only. S/390 specific setup of interrupts et al. is done
 * much later in init_channel_subsystem().
 */
void __init
init_IRQ(void)
{
        /* nothing... */
}