text: /*
   *  arch/s390/kernel/setup.c
   *
   *  S390 version
   *    Copyright (C) IBM Corp. 1999,2012
   *    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
   */
  
  #define KMSG_COMPONENT "setup"
  #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  
  #include <linux/errno.h>
  #include <linux/module.h>
  #include <linux/sched.h>
  #include <linux/kernel.h>
  #include <linux/memblock.h>
  #include <linux/mm.h>
  #include <linux/stddef.h>
  #include <linux/unistd.h>
  #include <linux/ptrace.h>
  #include <linux/user.h>
  #include <linux/tty.h>
  #include <linux/ioport.h>
  #include <linux/delay.h>
  #include <linux/init.h>
  #include <linux/initrd.h>
  #include <linux/bootmem.h>
  #include <linux/root_dev.h>
  #include <linux/console.h>
  #include <linux/kernel_stat.h>
  #include <linux/device.h>
  #include <linux/notifier.h>
  #include <linux/pfn.h>
  #include <linux/ctype.h>
  #include <linux/reboot.h>
  #include <linux/topology.h>
  #include <linux/ftrace.h>
  #include <linux/kexec.h>
  #include <linux/crash_dump.h>
  #include <linux/memory.h>
  #include <linux/compat.h>
  
  #include <asm/ipl.h>
  #include <asm/uaccess.h>
  #include <asm/facility.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>
  #include <asm/sections.h>
  #include <asm/ebcdic.h>
  #include <asm/kvm_virtio.h>
  #include <asm/diag.h>
  #include <asm/os_info.h>
  #include "entry.h"
  
  long psw_kernel_bits	= PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
  			  PSW_MASK_EA | PSW_MASK_BA;
  long psw_user_bits	= PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT |
  			  PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK |
  			  PSW_MASK_PSTATE | PSW_ASC_HOME;
  
  /*
   * User copy operations.
   */
  struct uaccess_ops uaccess;
  EXPORT_SYMBOL(uaccess);
  
  /*
   * Machine setup..
   */
  unsigned int console_mode = 0;
  EXPORT_SYMBOL(console_mode);
  
  unsigned int console_devno = -1;
  EXPORT_SYMBOL(console_devno);
  
  unsigned int console_irq = -1;
  EXPORT_SYMBOL(console_irq);
  
  unsigned long elf_hwcap = 0;
  char elf_platform[ELF_PLATFORM_SIZE];
  
  struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  
  int __initdata memory_end_set;
  unsigned long __initdata memory_end;
  
  unsigned long VMALLOC_START;
  EXPORT_SYMBOL(VMALLOC_START);
  
  unsigned long VMALLOC_END;
  EXPORT_SYMBOL(VMALLOC_END);
  
  struct page *vmemmap;
  EXPORT_SYMBOL(vmemmap);
  
  /* An array with a pointer to the lowcore of every CPU. */
  struct _lowcore *lowcore_ptr[NR_CPUS];
  EXPORT_SYMBOL(lowcore_ptr);
  
  /*
   * 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>
  
  /*
   * 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 void __init set_preferred_console(void)
  {
  	if (MACHINE_IS_KVM)
  		add_preferred_console("hvc", 0, NULL);
  	else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
  		add_preferred_console("ttyS", 0, NULL);
  	else if (CONSOLE_IS_3270)
  		add_preferred_console("tty3270", 0, NULL);
  }
  
  static int __init conmode_setup(char *str)
  {
  #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_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
  	set_preferred_console();
          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) || defined(CONFIG_SCLP_VT220_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) || defined(CONFIG_SCLP_VT220_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) || defined(CONFIG_SCLP_VT220_CONSOLE)
  			SET_CONSOLE_SCLP;
  #endif
  		}
  	} else {
  #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
  		SET_CONSOLE_SCLP;
  #endif
  	}
  }
  
  #ifdef CONFIG_ZFCPDUMP
  static void __init setup_zfcpdump(unsigned int console_devno)
  {
  	static char str[41];
  
  	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
  		return;
  	if (OLDMEM_BASE)
  		return;
  	if (console_devno != -1)
  		sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
  			ipl_info.data.fcp.dev_id.devno, console_devno);
  	else
  		sprintf(str, " cio_ignore=all,!0.0.%04x",
  			ipl_info.data.fcp.dev_id.devno);
  	strcat(boot_command_line, str);
  	console_loglevel = 2;
  }
  #else
  static inline void setup_zfcpdump(unsigned int console_devno) {}
  #endif /* CONFIG_ZFCPDUMP */
  
   /*
   * Reboot, halt and power_off stubs. They just call _machine_restart,
   * _machine_halt or _machine_power_off. 
   */
  
  void machine_restart(char *command)
  {
  	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
  		/*
  		 * Only unblank the console if we are called in enabled
  		 * context or a bust_spinlocks cleared the way for us.
  		 */
  		console_unblank();
  	_machine_restart(command);
  }
  
  void machine_halt(void)
  {
  	if (!in_interrupt() || oops_in_progress)
  		/*
  		 * Only unblank the console if we are called in enabled
  		 * context or a bust_spinlocks cleared the way for us.
  		 */
  		console_unblank();
  	_machine_halt();
  }
  
  void machine_power_off(void)
  {
  	if (!in_interrupt() || oops_in_progress)
  		/*
  		 * Only unblank the console if we are called in enabled
  		 * context or a bust_spinlocks cleared the way for us.
  		 */
  		console_unblank();
  	_machine_power_off();
  }
  
  /*
   * Dummy power off function.
   */
  void (*pm_power_off)(void) = machine_power_off;
  
  static int __init early_parse_mem(char *p)
  {
  	memory_end = memparse(p, &p);
  	memory_end_set = 1;
  	return 0;
  }
  early_param("mem", early_parse_mem);
  
  static int __init parse_vmalloc(char *arg)
  {
  	if (!arg)
  		return -EINVAL;
  	VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
  	return 0;
  }
  early_param("vmalloc", parse_vmalloc);
  
  unsigned int user_mode = HOME_SPACE_MODE;
  EXPORT_SYMBOL_GPL(user_mode);
  
  static int set_amode_primary(void)
  {
  	psw_kernel_bits = (psw_kernel_bits & ~PSW_MASK_ASC) | PSW_ASC_HOME;
  	psw_user_bits = (psw_user_bits & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY;
  #ifdef CONFIG_COMPAT
  	psw32_user_bits =
  		(psw32_user_bits & ~PSW32_MASK_ASC) | PSW32_ASC_PRIMARY;
  #endif
  
  	if (MACHINE_HAS_MVCOS) {
  		memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
  		return 1;
  	} else {
  		memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
  		return 0;
  	}
  }
  
  /*
   * Switch kernel/user addressing modes?
   */
  static int __init early_parse_switch_amode(char *p)
  {
  	user_mode = PRIMARY_SPACE_MODE;
  	return 0;
  }
  early_param("switch_amode", early_parse_switch_amode);
  
  static int __init early_parse_user_mode(char *p)
  {
  	if (p && strcmp(p, "primary") == 0)
  		user_mode = PRIMARY_SPACE_MODE;
  	else if (!p || strcmp(p, "home") == 0)
  		user_mode = HOME_SPACE_MODE;
  	else
  		return 1;
  	return 0;
  }
  early_param("user_mode", early_parse_user_mode);
  
  static void setup_addressing_mode(void)
  {
  	if (user_mode == PRIMARY_SPACE_MODE) {
  		if (set_amode_primary())
  			pr_info("Address spaces switched, "
  				"mvcos available\n");
  		else
  			pr_info("Address spaces switched, "
  				"mvcos not available\n");
  	}
  }
  
  void *restart_stack __attribute__((__section__(".data")));
  
  static void __init setup_lowcore(void)
  {
  	struct _lowcore *lc;
  
  	/*
  	 * Setup lowcore for boot cpu
  	 */
  	BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
  	lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
  	lc->restart_psw.mask = psw_kernel_bits;
  	lc->restart_psw.addr =
  		PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
  	lc->external_new_psw.mask = psw_kernel_bits |
  		PSW_MASK_DAT | PSW_MASK_MCHECK;
  	lc->external_new_psw.addr =
  		PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
  	lc->svc_new_psw.mask = psw_kernel_bits |
  		PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
  	lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
  	lc->program_new_psw.mask = psw_kernel_bits |
  		PSW_MASK_DAT | PSW_MASK_MCHECK;
  	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 |
  		PSW_MASK_DAT | PSW_MASK_MCHECK;
  	lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
  	lc->clock_comparator = -1ULL;
  	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;
  	lc->machine_flags = S390_lowcore.machine_flags;
  	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
  	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
  	       MAX_FACILITY_BIT/8);
  #ifndef CONFIG_64BIT
  	if (MACHINE_HAS_IEEE) {
  		lc->extended_save_area_addr = (__u32)
  			__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
  		/* enable extended save area */
  		__ctl_set_bit(14, 29);
  	}
  #else
  	lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
  #endif
  	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
  	lc->async_enter_timer = S390_lowcore.async_enter_timer;
  	lc->exit_timer = S390_lowcore.exit_timer;
  	lc->user_timer = S390_lowcore.user_timer;
  	lc->system_timer = S390_lowcore.system_timer;
  	lc->steal_timer = S390_lowcore.steal_timer;
  	lc->last_update_timer = S390_lowcore.last_update_timer;
  	lc->last_update_clock = S390_lowcore.last_update_clock;
  	lc->ftrace_func = S390_lowcore.ftrace_func;
  
  	restart_stack = __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0);
  	restart_stack += ASYNC_SIZE;
  
  	/*
  	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
  	 * restart data to the absolute zero lowcore. This is necesary if
  	 * PSW restart is done on an offline CPU that has lowcore zero.
  	 */
  	lc->restart_stack = (unsigned long) restart_stack;
  	lc->restart_fn = (unsigned long) do_restart;
  	lc->restart_data = 0;
  	lc->restart_source = -1UL;
  	memcpy(&S390_lowcore.restart_stack, &lc->restart_stack,
  	       4*sizeof(unsigned long));
  	copy_to_absolute_zero(&S390_lowcore.restart_psw,
  			      &lc->restart_psw, sizeof(psw_t));
  
  	set_prefix((u32)(unsigned long) lc);
  	lowcore_ptr[0] = lc;
  }
  
  static struct resource code_resource = {
  	.name  = "Kernel code",
  	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
  };
  
  static struct resource data_resource = {
  	.name = "Kernel data",
  	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
  };
  
  static struct resource bss_resource = {
  	.name = "Kernel bss",
  	.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
  };
  
  static struct resource __initdata *standard_resources[] = {
  	&code_resource,
  	&data_resource,
  	&bss_resource,
  };
  
  static void __init setup_resources(void)
  {
  	struct resource *res, *std_res, *sub_res;
  	int i, j;
  
  	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;
  	bss_resource.start = (unsigned long) &__bss_start;
  	bss_resource.end = (unsigned long) &__bss_stop - 1;
  
  	for (i = 0; i < MEMORY_CHUNKS; i++) {
  		if (!memory_chunk[i].size)
  			continue;
  		if (memory_chunk[i].type == CHUNK_OLDMEM ||
  		    memory_chunk[i].type == CHUNK_CRASHK)
  			continue;
  		res = alloc_bootmem_low(sizeof(*res));
  		res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
  		switch (memory_chunk[i].type) {
  		case CHUNK_READ_WRITE:
  		case CHUNK_CRASHK:
  			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 = res->start + memory_chunk[i].size - 1;
  		request_resource(&iomem_resource, res);
  
  		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
  			std_res = standard_resources[j];
  			if (std_res->start < res->start ||
  			    std_res->start > res->end)
  				continue;
  			if (std_res->end > res->end) {
  				sub_res = alloc_bootmem_low(sizeof(*sub_res));
  				*sub_res = *std_res;
  				sub_res->end = res->end;
  				std_res->start = res->end + 1;
  				request_resource(res, sub_res);
  			} else {
  				request_resource(res, std_res);
  			}
  		}
  	}
  }
  
  unsigned long real_memory_size;
  EXPORT_SYMBOL_GPL(real_memory_size);
  
  static void __init setup_memory_end(void)
  {
  	unsigned long vmax, vmalloc_size, tmp;
  	int i;
  
  
  #ifdef CONFIG_ZFCPDUMP
  	if (ipl_info.type == IPL_TYPE_FCP_DUMP && !OLDMEM_BASE) {
  		memory_end = ZFCPDUMP_HSA_SIZE;
  		memory_end_set = 1;
  	}
  #endif
  	real_memory_size = 0;
  	memory_end &= PAGE_MASK;
  
  	/*
  	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
  	 * extra checks that HOLES_IN_ZONE would require.
  	 */
  	for (i = 0; i < MEMORY_CHUNKS; i++) {
  		unsigned long start, end;
  		struct mem_chunk *chunk;
  		unsigned long align;
  
  		chunk = &memory_chunk[i];
  		align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
  		start = (chunk->addr + align - 1) & ~(align - 1);
  		end = (chunk->addr + chunk->size) & ~(align - 1);
  		if (start >= end)
  			memset(chunk, 0, sizeof(*chunk));
  		else {
  			chunk->addr = start;
  			chunk->size = end - start;
  		}
  		real_memory_size = max(real_memory_size,
  				       chunk->addr + chunk->size);
  	}
  
  	/* Choose kernel address space layout: 2, 3, or 4 levels. */
  #ifdef CONFIG_64BIT
  	vmalloc_size = VMALLOC_END ?: 128UL << 30;
  	tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
  	tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
  	if (tmp <= (1UL << 42))
  		vmax = 1UL << 42;	/* 3-level kernel page table */
  	else
  		vmax = 1UL << 53;	/* 4-level kernel page table */
  #else
  	vmalloc_size = VMALLOC_END ?: 96UL << 20;
  	vmax = 1UL << 31;		/* 2-level kernel page table */
  #endif
  	/* vmalloc area is at the end of the kernel address space. */
  	VMALLOC_END = vmax;
  	VMALLOC_START = vmax - vmalloc_size;
  
  	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
  	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
  	tmp = VMALLOC_START - tmp * sizeof(struct page);
  	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
  	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
  	vmemmap = (struct page *) tmp;
  
  	/* Take care that memory_end is set and <= vmemmap */
  	memory_end = min(memory_end ?: real_memory_size, tmp);
  
  	/* Fixup memory chunk array to fit into 0..memory_end */
  	for (i = 0; i < MEMORY_CHUNKS; i++) {
  		struct mem_chunk *chunk = &memory_chunk[i];
  
  		if (chunk->addr >= memory_end) {
  			memset(chunk, 0, sizeof(*chunk));
  			continue;
  		}
  		if (chunk->addr + chunk->size > memory_end)
  			chunk->size = memory_end - chunk->addr;
  	}
  }
  
  static void __init setup_vmcoreinfo(void)
  {
  #ifdef CONFIG_KEXEC
  	unsigned long ptr = paddr_vmcoreinfo_note();
  
  	copy_to_absolute_zero(&S390_lowcore.vmcore_info, &ptr, sizeof(ptr));
  #endif
  }
  
  #ifdef CONFIG_CRASH_DUMP
  
  /*
   * Find suitable location for crashkernel memory
   */
  static unsigned long __init find_crash_base(unsigned long crash_size,
  					    char **msg)
  {
  	unsigned long crash_base;
  	struct mem_chunk *chunk;
  	int i;
  
  	if (memory_chunk[0].size < crash_size) {
  		*msg = "first memory chunk must be at least crashkernel size";
  		return 0;
  	}
  	if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
  		return OLDMEM_BASE;
  
  	for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
  		chunk = &memory_chunk[i];
  		if (chunk->size == 0)
  			continue;
  		if (chunk->type != CHUNK_READ_WRITE)
  			continue;
  		if (chunk->size < crash_size)
  			continue;
  		crash_base = (chunk->addr + chunk->size) - crash_size;
  		if (crash_base < crash_size)
  			continue;
  		if (crash_base < ZFCPDUMP_HSA_SIZE_MAX)
  			continue;
  		if (crash_base < (unsigned long) INITRD_START + INITRD_SIZE)
  			continue;
  		return crash_base;
  	}
  	*msg = "no suitable area found";
  	return 0;
  }
  
  /*
   * Check if crash_base and crash_size is valid
   */
  static int __init verify_crash_base(unsigned long crash_base,
  				    unsigned long crash_size,
  				    char **msg)
  {
  	struct mem_chunk *chunk;
  	int i;
  
  	/*
  	 * Because we do the swap to zero, we must have at least 'crash_size'
  	 * bytes free space before crash_base
  	 */
  	if (crash_size > crash_base) {
  		*msg = "crashkernel offset must be greater than size";
  		return -EINVAL;
  	}
  
  	/* First memory chunk must be at least crash_size */
  	if (memory_chunk[0].size < crash_size) {
  		*msg = "first memory chunk must be at least crashkernel size";
  		return -EINVAL;
  	}
  	/* Check if we fit into the respective memory chunk */
  	for (i = 0; i < MEMORY_CHUNKS; i++) {
  		chunk = &memory_chunk[i];
  		if (chunk->size == 0)
  			continue;
  		if (crash_base < chunk->addr)
  			continue;
  		if (crash_base >= chunk->addr + chunk->size)
  			continue;
  		/* we have found the memory chunk */
  		if (crash_base + crash_size > chunk->addr + chunk->size) {
  			*msg = "selected memory chunk is too small for "
  				"crashkernel memory";
  			return -EINVAL;
  		}
  		return 0;
  	}
  	*msg = "invalid memory range specified";
  	return -EINVAL;
  }
  
  /*
   * Reserve kdump memory by creating a memory hole in the mem_chunk array
   */
  static void __init reserve_kdump_bootmem(unsigned long addr, unsigned long size,
  					 int type)
  {
  	create_mem_hole(memory_chunk, addr, size, type);
  }
  
  /*
   * When kdump is enabled, we have to ensure that no memory from
   * the area [0 - crashkernel memory size] and
   * [crashk_res.start - crashk_res.end] is set offline.
   */
  static int kdump_mem_notifier(struct notifier_block *nb,
  			      unsigned long action, void *data)
  {
  	struct memory_notify *arg = data;
  
  	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
  		return NOTIFY_BAD;
  	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
  		return NOTIFY_OK;
  	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
  		return NOTIFY_OK;
  	return NOTIFY_BAD;
  }
  
  static struct notifier_block kdump_mem_nb = {
  	.notifier_call = kdump_mem_notifier,
  };
  
  #endif
  
  /*
   * Make sure that oldmem, where the dump is stored, is protected
   */
  static void reserve_oldmem(void)
  {
  #ifdef CONFIG_CRASH_DUMP
  	if (!OLDMEM_BASE)
  		return;
  
  	reserve_kdump_bootmem(OLDMEM_BASE, OLDMEM_SIZE, CHUNK_OLDMEM);
  	reserve_kdump_bootmem(OLDMEM_SIZE, memory_end - OLDMEM_SIZE,
  			      CHUNK_OLDMEM);
  	if (OLDMEM_BASE + OLDMEM_SIZE == real_memory_size)
  		saved_max_pfn = PFN_DOWN(OLDMEM_BASE) - 1;
  	else
  		saved_max_pfn = PFN_DOWN(real_memory_size) - 1;
  #endif
  }
  
  /*
   * Reserve memory for kdump kernel to be loaded with kexec
   */
  static void __init reserve_crashkernel(void)
  {
  #ifdef CONFIG_CRASH_DUMP
  	unsigned long long crash_base, crash_size;
  	char *msg = NULL;
  	int rc;
  
  	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
  			       &crash_base);
  	if (rc || crash_size == 0)
  		return;
  	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
  	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
  	if (register_memory_notifier(&kdump_mem_nb))
  		return;
  	if (!crash_base)
  		crash_base = find_crash_base(crash_size, &msg);
  	if (!crash_base) {
  		pr_info("crashkernel reservation failed: %s\n", msg);
  		unregister_memory_notifier(&kdump_mem_nb);
  		return;
  	}
  	if (verify_crash_base(crash_base, crash_size, &msg)) {
  		pr_info("crashkernel reservation failed: %s\n", msg);
  		unregister_memory_notifier(&kdump_mem_nb);
  		return;
  	}
  	if (!OLDMEM_BASE && MACHINE_IS_VM)
  		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
  	crashk_res.start = crash_base;
  	crashk_res.end = crash_base + crash_size - 1;
  	insert_resource(&iomem_resource, &crashk_res);
  	reserve_kdump_bootmem(crash_base, crash_size, CHUNK_CRASHK);
  	pr_info("Reserving %lluMB of memory at %lluMB "
  		"for crashkernel (System RAM: %luMB)\n",
  		crash_size >> 20, crash_base >> 20, memory_end >> 20);
  	os_info_crashkernel_add(crash_base, crash_size);
  #endif
  }
  
  static void __init setup_memory(void)
  {
          unsigned long bootmap_size;
  	unsigned long start_pfn, end_pfn;
  	int i;
  
  	/*
  	 * partially used pages are not usable - thus
  	 * we are rounding upwards:
  	 */
  	start_pfn = PFN_UP(__pa(&_end));
  	end_pfn = max_pfn = PFN_DOWN(memory_end);
  
  #ifdef CONFIG_BLK_DEV_INITRD
  	/*
  	 * Move the initrd in case the bitmap of the bootmem allocater
  	 * would overwrite it.
  	 */
  
  	if (INITRD_START && INITRD_SIZE) {
  		unsigned long bmap_size;
  		unsigned long start;
  
  		bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
  		bmap_size = PFN_PHYS(bmap_size);
  
  		if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
  			start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
  
  #ifdef CONFIG_CRASH_DUMP
  			if (OLDMEM_BASE) {
  				/* Move initrd behind kdump oldmem */
  				if (start + INITRD_SIZE > OLDMEM_BASE &&
  				    start < OLDMEM_BASE + OLDMEM_SIZE)
  					start = OLDMEM_BASE + OLDMEM_SIZE;
  			}
  #endif
  			if (start + INITRD_SIZE > memory_end) {
  				pr_err("initrd extends beyond end of "
  				       "memory (0x%08lx > 0x%08lx) "
  				       "disabling initrd\n",
  				       start + INITRD_SIZE, memory_end);
  				INITRD_START = INITRD_SIZE = 0;
  			} else {
  				pr_info("Moving initrd (0x%08lx -> "
  					"0x%08lx, size: %ld)\n",
  					INITRD_START, start, INITRD_SIZE);
  				memmove((void *) start, (void *) INITRD_START,
  					INITRD_SIZE);
  				INITRD_START = start;
  			}
  		}
  	}
  #endif
  
  	/*
  	 * Initialize the boot-time allocator
  	 */
  	bootmap_size = init_bootmem(start_pfn, end_pfn);
  
  	/*
  	 * Register RAM areas with the bootmem allocator.
  	 */
  
  	for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
  		unsigned long start_chunk, end_chunk, pfn;
  
  		if (memory_chunk[i].type != CHUNK_READ_WRITE &&
  		    memory_chunk[i].type != CHUNK_CRASHK)
  			continue;
  		start_chunk = PFN_DOWN(memory_chunk[i].addr);
  		end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
  		end_chunk = min(end_chunk, end_pfn);
  		if (start_chunk >= end_chunk)
  			continue;
  		memblock_add_node(PFN_PHYS(start_chunk),
  				  PFN_PHYS(end_chunk - start_chunk), 0);
  		pfn = max(start_chunk, start_pfn);
  		for (; pfn < end_chunk; pfn++)
  			page_set_storage_key(PFN_PHYS(pfn),
  					     PAGE_DEFAULT_KEY, 0);
  	}
  
  	psw_set_key(PAGE_DEFAULT_KEY);
  
  	free_bootmem_with_active_regions(0, max_pfn);
  
  	/*
  	 * Reserve memory used for lowcore/command line/kernel image.
  	 */
  	reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
  	reserve_bootmem((unsigned long)_stext,
  			PFN_PHYS(start_pfn) - (unsigned long)_stext,
  			BOOTMEM_DEFAULT);
  	/*
  	 * 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,
  			BOOTMEM_DEFAULT);
  
  #ifdef CONFIG_CRASH_DUMP
  	if (crashk_res.start)
  		reserve_bootmem(crashk_res.start,
  				crashk_res.end - crashk_res.start + 1,
  				BOOTMEM_DEFAULT);
  	if (is_kdump_kernel())
  		reserve_bootmem(elfcorehdr_addr - OLDMEM_BASE,
  				PAGE_ALIGN(elfcorehdr_size), BOOTMEM_DEFAULT);
  #endif
  #ifdef CONFIG_BLK_DEV_INITRD
  	if (INITRD_START && INITRD_SIZE) {
  		if (INITRD_START + INITRD_SIZE <= memory_end) {
  			reserve_bootmem(INITRD_START, INITRD_SIZE,
  					BOOTMEM_DEFAULT);
  			initrd_start = INITRD_START;
  			initrd_end = initrd_start + INITRD_SIZE;
  		} else {
  			pr_err("initrd extends beyond end of "
  			       "memory (0x%08lx > 0x%08lx) "
  			       "disabling initrd\n",
  			       initrd_start + INITRD_SIZE, memory_end);
  			initrd_start = initrd_end = 0;
  		}
  	}
  #endif
  }
  
  /*
   * Setup hardware capabilities.
   */
  static void __init setup_hwcaps(void)
  {
  	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
  	struct cpuid cpu_id;
  	int i;
  
  	/*
  	 * The store facility list bits numbers as found in the principles
  	 * of operation are numbered with bit 1UL<<31 as number 0 to
  	 * bit 1UL<<0 as number 31.
  	 *   Bit 0: instructions named N3, "backported" to esa-mode
  	 *   Bit 2: z/Architecture mode is active
  	 *   Bit 7: the store-facility-list-extended facility is installed
  	 *   Bit 17: the message-security assist is installed
  	 *   Bit 19: the long-displacement facility is installed
  	 *   Bit 21: the extended-immediate facility is installed
  	 *   Bit 22: extended-translation facility 3 is installed
  	 *   Bit 30: extended-translation facility 3 enhancement facility
  	 * These get translated to:
  	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
  	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
  	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
  	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
  	 */
  	for (i = 0; i < 6; i++)
  		if (test_facility(stfl_bits[i]))
  			elf_hwcap |= 1UL << i;
  
  	if (test_facility(22) && test_facility(30))
  		elf_hwcap |= HWCAP_S390_ETF3EH;
  
  	/*
  	 * Check for additional facilities with store-facility-list-extended.
  	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
  	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
  	 * as stored by stfl, bits 32-xxx contain additional facilities.
  	 * How many facility words are stored depends on the number of
  	 * doublewords passed to the instruction. The additional facilities
  	 * are:
  	 *   Bit 42: decimal floating point facility is installed
  	 *   Bit 44: perform floating point operation facility is installed
  	 * translated to:
  	 *   HWCAP_S390_DFP bit 6 (42 && 44).
  	 */
  	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
  		elf_hwcap |= HWCAP_S390_DFP;
  
  	/*
  	 * Huge page support HWCAP_S390_HPAGE is bit 7.
  	 */
  	if (MACHINE_HAS_HPAGE)
  		elf_hwcap |= HWCAP_S390_HPAGE;
  
  	/*
  	 * 64-bit register support for 31-bit processes
  	 * HWCAP_S390_HIGH_GPRS is bit 9.
  	 */
  	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
  
  	get_cpu_id(&cpu_id);
  	switch (cpu_id.machine) {
  	case 0x9672:
  #if !defined(CONFIG_64BIT)
  	default:	/* Use "g5" as default for 31 bit kernels. */
  #endif
  		strcpy(elf_platform, "g5");
  		break;
  	case 0x2064:
  	case 0x2066:
  #if defined(CONFIG_64BIT)
  	default:	/* Use "z900" as default for 64 bit kernels. */
  #endif
  		strcpy(elf_platform, "z900");
  		break;
  	case 0x2084:
  	case 0x2086:
  		strcpy(elf_platform, "z990");
  		break;
  	case 0x2094:
  	case 0x2096:
  		strcpy(elf_platform, "z9-109");
  		break;
  	case 0x2097:
  	case 0x2098:
  		strcpy(elf_platform, "z10");
  		break;
  	case 0x2817:
  	case 0x2818:
  		strcpy(elf_platform, "z196");
  		break;
  	}
  }
  
  /*
   * 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_64BIT
  	if (MACHINE_IS_VM)
  		pr_info("Linux is running as a z/VM "
  			"guest operating system in 31-bit mode\n");
  	else if (MACHINE_IS_LPAR)
  		pr_info("Linux is running natively in 31-bit mode\n");
  	if (MACHINE_HAS_IEEE)
  		pr_info("The hardware system has IEEE compatible "
  			"floating point units\n");
  	else
  		pr_info("The hardware system has no IEEE compatible "
  			"floating point units\n");
  #else /* CONFIG_64BIT */
  	if (MACHINE_IS_VM)
  		pr_info("Linux is running as a z/VM "
  			"guest operating system in 64-bit mode\n");
  	else if (MACHINE_IS_KVM)
  		pr_info("Linux is running under KVM in 64-bit mode\n");
  	else if (MACHINE_IS_LPAR)
  		pr_info("Linux is running natively in 64-bit mode\n");
  #endif /* CONFIG_64BIT */
  
  	/* Have one command line that is parsed and saved in /proc/cmdline */
  	/* boot_command_line has been already set up in early.c */
  	*cmdline_p = boot_command_line;
  
          ROOT_DEV = Root_RAM0;
  
  	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;
  
  	if (MACHINE_HAS_MVCOS)
  		memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
  	else
  		memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
  
  	parse_early_param();
  
  	os_info_init();
  	setup_ipl();
  	setup_memory_end();
  	setup_addressing_mode();
  	reserve_oldmem();
  	reserve_crashkernel();
  	setup_memory();
  	setup_resources();
  	setup_vmcoreinfo();
  	setup_lowcore();
  
          cpu_init();
  	s390_init_cpu_topology();
  
  	/*
  	 * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
  	 */
  	setup_hwcaps();
  
  	/*
  	 * Create kernel page tables and switch to virtual addressing.
  	 */
          paging_init();
  
          /* Setup default console */
  	conmode_default();
  	set_preferred_console();
  
  	/* Setup zfcpdump support */
  	setup_zfcpdump(console_devno);
  }
  