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v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  S390 version
   4 *    Copyright IBM Corp. 1999, 2012
   5 *    Author(s): Hartmut Penner (hp@de.ibm.com),
   6 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7 *
   8 *  Derived from "arch/i386/kernel/setup.c"
   9 *    Copyright (C) 1995, Linus Torvalds
  10 */
  11
  12/*
  13 * This file handles the architecture-dependent parts of initialization
  14 */
  15
  16#define KMSG_COMPONENT "setup"
  17#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  18
  19#include <linux/errno.h>
  20#include <linux/export.h>
  21#include <linux/sched.h>
  22#include <linux/sched/task.h>
  23#include <linux/cpu.h>
  24#include <linux/kernel.h>
  25#include <linux/memblock.h>
  26#include <linux/mm.h>
  27#include <linux/stddef.h>
  28#include <linux/unistd.h>
  29#include <linux/ptrace.h>
  30#include <linux/random.h>
  31#include <linux/user.h>
  32#include <linux/tty.h>
  33#include <linux/ioport.h>
  34#include <linux/delay.h>
  35#include <linux/init.h>
  36#include <linux/initrd.h>
 
  37#include <linux/root_dev.h>
  38#include <linux/console.h>
  39#include <linux/kernel_stat.h>
  40#include <linux/dma-map-ops.h>
  41#include <linux/device.h>
  42#include <linux/notifier.h>
  43#include <linux/pfn.h>
  44#include <linux/ctype.h>
  45#include <linux/reboot.h>
  46#include <linux/topology.h>
  47#include <linux/kexec.h>
  48#include <linux/crash_dump.h>
  49#include <linux/memory.h>
  50#include <linux/compat.h>
  51#include <linux/start_kernel.h>
  52#include <linux/hugetlb.h>
  53#include <linux/kmemleak.h>
  54
  55#include <asm/archrandom.h>
  56#include <asm/boot_data.h>
  57#include <asm/ipl.h>
  58#include <asm/facility.h>
  59#include <asm/smp.h>
  60#include <asm/mmu_context.h>
  61#include <asm/cpcmd.h>
  62#include <asm/abs_lowcore.h>
  63#include <asm/nmi.h>
  64#include <asm/irq.h>
  65#include <asm/page.h>
  66#include <asm/ptrace.h>
  67#include <asm/sections.h>
  68#include <asm/ebcdic.h>
  69#include <asm/diag.h>
  70#include <asm/os_info.h>
  71#include <asm/sclp.h>
  72#include <asm/stacktrace.h>
  73#include <asm/sysinfo.h>
  74#include <asm/numa.h>
  75#include <asm/alternative.h>
  76#include <asm/nospec-branch.h>
  77#include <asm/mem_detect.h>
  78#include <asm/maccess.h>
  79#include <asm/uv.h>
  80#include <asm/asm-offsets.h>
  81#include "entry.h"
  82
  83/*
  84 * Machine setup..
  85 */
  86unsigned int console_mode = 0;
  87EXPORT_SYMBOL(console_mode);
  88
  89unsigned int console_devno = -1;
  90EXPORT_SYMBOL(console_devno);
  91
  92unsigned int console_irq = -1;
  93EXPORT_SYMBOL(console_irq);
  94
  95/*
  96 * Some code and data needs to stay below 2 GB, even when the kernel would be
  97 * relocated above 2 GB, because it has to use 31 bit addresses.
  98 * Such code and data is part of the .amode31 section.
  99 */
 100unsigned long __amode31_ref __samode31 = (unsigned long)&_samode31;
 101unsigned long __amode31_ref __eamode31 = (unsigned long)&_eamode31;
 102unsigned long __amode31_ref __stext_amode31 = (unsigned long)&_stext_amode31;
 103unsigned long __amode31_ref __etext_amode31 = (unsigned long)&_etext_amode31;
 104struct exception_table_entry __amode31_ref *__start_amode31_ex_table = _start_amode31_ex_table;
 105struct exception_table_entry __amode31_ref *__stop_amode31_ex_table = _stop_amode31_ex_table;
 106
 107/*
 108 * Control registers CR2, CR5 and CR15 are initialized with addresses
 109 * of tables that must be placed below 2G which is handled by the AMODE31
 110 * sections.
 111 * Because the AMODE31 sections are relocated below 2G at startup,
 112 * the content of control registers CR2, CR5 and CR15 must be updated
 113 * with new addresses after the relocation. The initial initialization of
 114 * control registers occurs in head64.S and then gets updated again after AMODE31
 115 * relocation. We must access the relevant AMODE31 tables indirectly via
 116 * pointers placed in the .amode31.refs linker section. Those pointers get
 117 * updated automatically during AMODE31 relocation and always contain a valid
 118 * address within AMODE31 sections.
 119 */
 120
 121static __amode31_data u32 __ctl_duct_amode31[16] __aligned(64);
 122
 123static __amode31_data u64 __ctl_aste_amode31[8] __aligned(64) = {
 124	[1] = 0xffffffffffffffff
 125};
 126
 127static __amode31_data u32 __ctl_duald_amode31[32] __aligned(128) = {
 128	0x80000000, 0, 0, 0,
 129	0x80000000, 0, 0, 0,
 130	0x80000000, 0, 0, 0,
 131	0x80000000, 0, 0, 0,
 132	0x80000000, 0, 0, 0,
 133	0x80000000, 0, 0, 0,
 134	0x80000000, 0, 0, 0,
 135	0x80000000, 0, 0, 0
 136};
 137
 138static __amode31_data u32 __ctl_linkage_stack_amode31[8] __aligned(64) = {
 139	0, 0, 0x89000000, 0,
 140	0, 0, 0x8a000000, 0
 141};
 142
 143static u64 __amode31_ref *__ctl_aste = __ctl_aste_amode31;
 144static u32 __amode31_ref *__ctl_duald = __ctl_duald_amode31;
 145static u32 __amode31_ref *__ctl_linkage_stack = __ctl_linkage_stack_amode31;
 146static u32 __amode31_ref *__ctl_duct = __ctl_duct_amode31;
 147
 148int __bootdata(noexec_disabled);
 149unsigned long __bootdata(ident_map_size);
 150struct mem_detect_info __bootdata(mem_detect);
 151struct initrd_data __bootdata(initrd_data);
 152
 153unsigned long __bootdata_preserved(__kaslr_offset);
 154unsigned long __bootdata(__amode31_base);
 155unsigned int __bootdata_preserved(zlib_dfltcc_support);
 156EXPORT_SYMBOL(zlib_dfltcc_support);
 157u64 __bootdata_preserved(stfle_fac_list[16]);
 158EXPORT_SYMBOL(stfle_fac_list);
 159u64 __bootdata_preserved(alt_stfle_fac_list[16]);
 160struct oldmem_data __bootdata_preserved(oldmem_data);
 161
 162unsigned long VMALLOC_START;
 163EXPORT_SYMBOL(VMALLOC_START);
 164
 165unsigned long VMALLOC_END;
 166EXPORT_SYMBOL(VMALLOC_END);
 167
 168struct page *vmemmap;
 169EXPORT_SYMBOL(vmemmap);
 170unsigned long vmemmap_size;
 171
 172unsigned long MODULES_VADDR;
 173unsigned long MODULES_END;
 174
 175/* An array with a pointer to the lowcore of every CPU. */
 176struct lowcore *lowcore_ptr[NR_CPUS];
 177EXPORT_SYMBOL(lowcore_ptr);
 178
 179DEFINE_STATIC_KEY_FALSE(cpu_has_bear);
 180
 181/*
 182 * The Write Back bit position in the physaddr is given by the SLPC PCI.
 183 * Leaving the mask zero always uses write through which is safe
 184 */
 185unsigned long mio_wb_bit_mask __ro_after_init;
 186
 187/*
 188 * This is set up by the setup-routine at boot-time
 189 * for S390 need to find out, what we have to setup
 190 * using address 0x10400 ...
 191 */
 192
 193#include <asm/setup.h>
 194
 195/*
 196 * condev= and conmode= setup parameter.
 197 */
 198
 199static int __init condev_setup(char *str)
 200{
 201	int vdev;
 202
 203	vdev = simple_strtoul(str, &str, 0);
 204	if (vdev >= 0 && vdev < 65536) {
 205		console_devno = vdev;
 206		console_irq = -1;
 207	}
 208	return 1;
 209}
 210
 211__setup("condev=", condev_setup);
 212
 213static void __init set_preferred_console(void)
 214{
 215	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
 216		add_preferred_console("ttyS", 0, NULL);
 217	else if (CONSOLE_IS_3270)
 218		add_preferred_console("tty3270", 0, NULL);
 219	else if (CONSOLE_IS_VT220)
 220		add_preferred_console("ttysclp", 0, NULL);
 221	else if (CONSOLE_IS_HVC)
 222		add_preferred_console("hvc", 0, NULL);
 223}
 224
 225static int __init conmode_setup(char *str)
 226{
 227#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 228	if (!strcmp(str, "hwc") || !strcmp(str, "sclp"))
 229                SET_CONSOLE_SCLP;
 230#endif
 231#if defined(CONFIG_TN3215_CONSOLE)
 232	if (!strcmp(str, "3215"))
 233		SET_CONSOLE_3215;
 234#endif
 235#if defined(CONFIG_TN3270_CONSOLE)
 236	if (!strcmp(str, "3270"))
 237		SET_CONSOLE_3270;
 238#endif
 239	set_preferred_console();
 240        return 1;
 241}
 242
 243__setup("conmode=", conmode_setup);
 244
 245static void __init conmode_default(void)
 246{
 247	char query_buffer[1024];
 248	char *ptr;
 249
 250        if (MACHINE_IS_VM) {
 251		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
 252		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
 253		ptr = strstr(query_buffer, "SUBCHANNEL =");
 254		console_irq = simple_strtoul(ptr + 13, NULL, 16);
 255		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
 256		ptr = strstr(query_buffer, "CONMODE");
 257		/*
 258		 * Set the conmode to 3215 so that the device recognition 
 259		 * will set the cu_type of the console to 3215. If the
 260		 * conmode is 3270 and we don't set it back then both
 261		 * 3215 and the 3270 driver will try to access the console
 262		 * device (3215 as console and 3270 as normal tty).
 263		 */
 264		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
 265		if (ptr == NULL) {
 266#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 267			SET_CONSOLE_SCLP;
 268#endif
 269			return;
 270		}
 271		if (str_has_prefix(ptr + 8, "3270")) {
 272#if defined(CONFIG_TN3270_CONSOLE)
 273			SET_CONSOLE_3270;
 274#elif defined(CONFIG_TN3215_CONSOLE)
 275			SET_CONSOLE_3215;
 276#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 277			SET_CONSOLE_SCLP;
 278#endif
 279		} else if (str_has_prefix(ptr + 8, "3215")) {
 280#if defined(CONFIG_TN3215_CONSOLE)
 281			SET_CONSOLE_3215;
 282#elif defined(CONFIG_TN3270_CONSOLE)
 283			SET_CONSOLE_3270;
 284#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 285			SET_CONSOLE_SCLP;
 286#endif
 287		}
 288	} else if (MACHINE_IS_KVM) {
 289		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
 290			SET_CONSOLE_VT220;
 291		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
 292			SET_CONSOLE_SCLP;
 293		else
 294			SET_CONSOLE_HVC;
 295	} else {
 296#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
 297		SET_CONSOLE_SCLP;
 298#endif
 299	}
 
 
 300}
 301
 302#ifdef CONFIG_CRASH_DUMP
 303static void __init setup_zfcpdump(void)
 304{
 305	if (!is_ipl_type_dump())
 306		return;
 307	if (oldmem_data.start)
 308		return;
 309	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
 310	console_loglevel = 2;
 311}
 312#else
 313static inline void setup_zfcpdump(void) {}
 314#endif /* CONFIG_CRASH_DUMP */
 315
 316 /*
 317 * Reboot, halt and power_off stubs. They just call _machine_restart,
 318 * _machine_halt or _machine_power_off. 
 319 */
 320
 321void machine_restart(char *command)
 322{
 323	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
 324		/*
 325		 * Only unblank the console if we are called in enabled
 326		 * context or a bust_spinlocks cleared the way for us.
 327		 */
 328		console_unblank();
 329	_machine_restart(command);
 330}
 331
 332void machine_halt(void)
 333{
 334	if (!in_interrupt() || oops_in_progress)
 335		/*
 336		 * Only unblank the console if we are called in enabled
 337		 * context or a bust_spinlocks cleared the way for us.
 338		 */
 339		console_unblank();
 340	_machine_halt();
 341}
 342
 343void machine_power_off(void)
 344{
 345	if (!in_interrupt() || oops_in_progress)
 346		/*
 347		 * Only unblank the console if we are called in enabled
 348		 * context or a bust_spinlocks cleared the way for us.
 349		 */
 350		console_unblank();
 351	_machine_power_off();
 352}
 353
 354/*
 355 * Dummy power off function.
 356 */
 357void (*pm_power_off)(void) = machine_power_off;
 358EXPORT_SYMBOL_GPL(pm_power_off);
 359
 360void *restart_stack;
 361
 362unsigned long stack_alloc(void)
 363{
 364#ifdef CONFIG_VMAP_STACK
 365	void *ret;
 366
 367	ret = __vmalloc_node(THREAD_SIZE, THREAD_SIZE, THREADINFO_GFP,
 368			     NUMA_NO_NODE, __builtin_return_address(0));
 369	kmemleak_not_leak(ret);
 370	return (unsigned long)ret;
 371#else
 372	return __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 373#endif
 374}
 375
 376void stack_free(unsigned long stack)
 377{
 378#ifdef CONFIG_VMAP_STACK
 379	vfree((void *) stack);
 380#else
 381	free_pages(stack, THREAD_SIZE_ORDER);
 382#endif
 383}
 
 384
 385int __init arch_early_irq_init(void)
 386{
 387	unsigned long stack;
 388
 389	stack = __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER);
 390	if (!stack)
 391		panic("Couldn't allocate async stack");
 392	S390_lowcore.async_stack = stack + STACK_INIT_OFFSET;
 393	return 0;
 394}
 
 395
 396void __init arch_call_rest_init(void)
 397{
 398	unsigned long stack;
 399
 400	smp_reinit_ipl_cpu();
 401	stack = stack_alloc();
 402	if (!stack)
 403		panic("Couldn't allocate kernel stack");
 404	current->stack = (void *) stack;
 405#ifdef CONFIG_VMAP_STACK
 406	current->stack_vm_area = (void *) stack;
 407#endif
 408	set_task_stack_end_magic(current);
 409	stack += STACK_INIT_OFFSET;
 410	S390_lowcore.kernel_stack = stack;
 411	call_on_stack_noreturn(rest_init, stack);
 412}
 413
 414static void __init setup_lowcore_dat_off(void)
 415{
 416	unsigned long int_psw_mask = PSW_KERNEL_BITS;
 417	struct lowcore *abs_lc, *lc;
 418	unsigned long mcck_stack;
 419	unsigned long flags;
 420
 421	if (IS_ENABLED(CONFIG_KASAN))
 422		int_psw_mask |= PSW_MASK_DAT;
 423
 424	/*
 425	 * Setup lowcore for boot cpu
 426	 */
 427	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
 428	lc = memblock_alloc_low(sizeof(*lc), sizeof(*lc));
 429	if (!lc)
 430		panic("%s: Failed to allocate %zu bytes align=%zx\n",
 431		      __func__, sizeof(*lc), sizeof(*lc));
 432
 433	lc->restart_psw.mask = PSW_KERNEL_BITS;
 434	lc->restart_psw.addr = (unsigned long) restart_int_handler;
 435	lc->external_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 
 436	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
 437	lc->svc_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 
 438	lc->svc_new_psw.addr = (unsigned long) system_call;
 439	lc->program_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 
 440	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
 441	lc->mcck_new_psw.mask = int_psw_mask;
 442	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
 443	lc->io_new_psw.mask = int_psw_mask | PSW_MASK_MCHECK;
 
 444	lc->io_new_psw.addr = (unsigned long) io_int_handler;
 445	lc->clock_comparator = clock_comparator_max;
 446	lc->nodat_stack = ((unsigned long) &init_thread_union)
 447		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
 
 
 
 
 
 
 448	lc->current_task = (unsigned long)&init_task;
 449	lc->lpp = LPP_MAGIC;
 450	lc->machine_flags = S390_lowcore.machine_flags;
 451	lc->preempt_count = S390_lowcore.preempt_count;
 452	nmi_alloc_mcesa_early(&lc->mcesad);
 453	lc->sys_enter_timer = S390_lowcore.sys_enter_timer;
 
 
 
 
 
 
 
 454	lc->exit_timer = S390_lowcore.exit_timer;
 455	lc->user_timer = S390_lowcore.user_timer;
 456	lc->system_timer = S390_lowcore.system_timer;
 457	lc->steal_timer = S390_lowcore.steal_timer;
 458	lc->last_update_timer = S390_lowcore.last_update_timer;
 459	lc->last_update_clock = S390_lowcore.last_update_clock;
 460
 461	/*
 462	 * Allocate the global restart stack which is the same for
 463	 * all CPUs in cast *one* of them does a PSW restart.
 464	 */
 465	restart_stack = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 466	if (!restart_stack)
 467		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 468		      __func__, THREAD_SIZE, THREAD_SIZE);
 469	restart_stack += STACK_INIT_OFFSET;
 470
 471	/*
 472	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
 473	 * restart data to the absolute zero lowcore. This is necessary if
 474	 * PSW restart is done on an offline CPU that has lowcore zero.
 475	 */
 476	lc->restart_stack = (unsigned long) restart_stack;
 477	lc->restart_fn = (unsigned long) do_restart;
 478	lc->restart_data = 0;
 479	lc->restart_source = -1U;
 480
 481	abs_lc = get_abs_lowcore(&flags);
 482	abs_lc->restart_stack = lc->restart_stack;
 483	abs_lc->restart_fn = lc->restart_fn;
 484	abs_lc->restart_data = lc->restart_data;
 485	abs_lc->restart_source = lc->restart_source;
 486	abs_lc->restart_psw = lc->restart_psw;
 487	abs_lc->mcesad = lc->mcesad;
 488	put_abs_lowcore(abs_lc, flags);
 489
 490	mcck_stack = (unsigned long)memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 491	if (!mcck_stack)
 492		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
 493		      __func__, THREAD_SIZE, THREAD_SIZE);
 494	lc->mcck_stack = mcck_stack + STACK_INIT_OFFSET;
 495
 
 496	lc->spinlock_lockval = arch_spin_lockval(0);
 497	lc->spinlock_index = 0;
 498	arch_spin_lock_setup(0);
 499	lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
 500	lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
 501	lc->preempt_count = PREEMPT_DISABLED;
 502
 503	set_prefix(__pa(lc));
 504	lowcore_ptr[0] = lc;
 505}
 506
 507static void __init setup_lowcore_dat_on(void)
 508{
 509	struct lowcore *abs_lc;
 510	unsigned long flags;
 511	int i;
 512
 513	__ctl_clear_bit(0, 28);
 514	S390_lowcore.external_new_psw.mask |= PSW_MASK_DAT;
 515	S390_lowcore.svc_new_psw.mask |= PSW_MASK_DAT;
 516	S390_lowcore.program_new_psw.mask |= PSW_MASK_DAT;
 517	S390_lowcore.mcck_new_psw.mask |= PSW_MASK_DAT;
 518	S390_lowcore.io_new_psw.mask |= PSW_MASK_DAT;
 519	__ctl_set_bit(0, 28);
 520	__ctl_store(S390_lowcore.cregs_save_area, 0, 15);
 521	if (abs_lowcore_map(0, lowcore_ptr[0], true))
 522		panic("Couldn't setup absolute lowcore");
 523	abs_lowcore_mapped = true;
 524	abs_lc = get_abs_lowcore(&flags);
 525	abs_lc->restart_flags = RESTART_FLAG_CTLREGS;
 526	abs_lc->program_new_psw = S390_lowcore.program_new_psw;
 527	for (i = 0; i < 16; i++)
 528		abs_lc->cregs_save_area[i] = S390_lowcore.cregs_save_area[i];
 529	put_abs_lowcore(abs_lc, flags);
 530}
 531
 532static struct resource code_resource = {
 533	.name  = "Kernel code",
 534	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 535};
 536
 537static struct resource data_resource = {
 538	.name = "Kernel data",
 539	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 540};
 541
 542static struct resource bss_resource = {
 543	.name = "Kernel bss",
 544	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
 545};
 546
 547static struct resource __initdata *standard_resources[] = {
 548	&code_resource,
 549	&data_resource,
 550	&bss_resource,
 551};
 552
 553static void __init setup_resources(void)
 554{
 555	struct resource *res, *std_res, *sub_res;
 556	phys_addr_t start, end;
 557	int j;
 558	u64 i;
 559
 560	code_resource.start = (unsigned long) _text;
 561	code_resource.end = (unsigned long) _etext - 1;
 562	data_resource.start = (unsigned long) _etext;
 563	data_resource.end = (unsigned long) _edata - 1;
 564	bss_resource.start = (unsigned long) __bss_start;
 565	bss_resource.end = (unsigned long) __bss_stop - 1;
 566
 567	for_each_mem_range(i, &start, &end) {
 568		res = memblock_alloc(sizeof(*res), 8);
 569		if (!res)
 570			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 571			      __func__, sizeof(*res), 8);
 572		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
 573
 574		res->name = "System RAM";
 575		res->start = start;
 576		/*
 577		 * In memblock, end points to the first byte after the
 578		 * range while in resourses, end points to the last byte in
 579		 * the range.
 580		 */
 581		res->end = end - 1;
 582		request_resource(&iomem_resource, res);
 583
 584		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
 585			std_res = standard_resources[j];
 586			if (std_res->start < res->start ||
 587			    std_res->start > res->end)
 588				continue;
 589			if (std_res->end > res->end) {
 590				sub_res = memblock_alloc(sizeof(*sub_res), 8);
 591				if (!sub_res)
 592					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 593					      __func__, sizeof(*sub_res), 8);
 594				*sub_res = *std_res;
 595				sub_res->end = res->end;
 596				std_res->start = res->end + 1;
 597				request_resource(res, sub_res);
 598			} else {
 599				request_resource(res, std_res);
 600			}
 601		}
 602	}
 603#ifdef CONFIG_CRASH_DUMP
 604	/*
 605	 * Re-add removed crash kernel memory as reserved memory. This makes
 606	 * sure it will be mapped with the identity mapping and struct pages
 607	 * will be created, so it can be resized later on.
 608	 * However add it later since the crash kernel resource should not be
 609	 * part of the System RAM resource.
 610	 */
 611	if (crashk_res.end) {
 612		memblock_add_node(crashk_res.start, resource_size(&crashk_res),
 613				  0, MEMBLOCK_NONE);
 614		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 615		insert_resource(&iomem_resource, &crashk_res);
 616	}
 617#endif
 618}
 619
 620static void __init setup_memory_end(void)
 621{
 622	memblock_remove(ident_map_size, PHYS_ADDR_MAX - ident_map_size);
 623	max_pfn = max_low_pfn = PFN_DOWN(ident_map_size);
 624	pr_notice("The maximum memory size is %luMB\n", ident_map_size >> 20);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 625}
 626
 627#ifdef CONFIG_CRASH_DUMP
 628
 629/*
 630 * When kdump is enabled, we have to ensure that no memory from the area
 631 * [0 - crashkernel memory size] is set offline - it will be exchanged with
 632 * the crashkernel memory region when kdump is triggered. The crashkernel
 633 * memory region can never get offlined (pages are unmovable).
 634 */
 635static int kdump_mem_notifier(struct notifier_block *nb,
 636			      unsigned long action, void *data)
 637{
 638	struct memory_notify *arg = data;
 639
 640	if (action != MEM_GOING_OFFLINE)
 641		return NOTIFY_OK;
 642	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
 643		return NOTIFY_BAD;
 644	return NOTIFY_OK;
 
 
 
 
 645}
 646
 647static struct notifier_block kdump_mem_nb = {
 648	.notifier_call = kdump_mem_notifier,
 649};
 650
 651#endif
 652
 653/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 654 * Reserve memory for kdump kernel to be loaded with kexec
 655 */
 656static void __init reserve_crashkernel(void)
 657{
 658#ifdef CONFIG_CRASH_DUMP
 659	unsigned long long crash_base, crash_size;
 660	phys_addr_t low, high;
 661	int rc;
 662
 663	rc = parse_crashkernel(boot_command_line, ident_map_size, &crash_size,
 664			       &crash_base);
 665
 666	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
 667	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
 668	if (rc || crash_size == 0)
 669		return;
 670
 671	if (memblock.memory.regions[0].size < crash_size) {
 672		pr_info("crashkernel reservation failed: %s\n",
 673			"first memory chunk must be at least crashkernel size");
 674		return;
 675	}
 676
 677	low = crash_base ?: oldmem_data.start;
 678	high = low + crash_size;
 679	if (low >= oldmem_data.start && high <= oldmem_data.start + oldmem_data.size) {
 680		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
 681		crash_base = low;
 682	} else {
 683		/* Find suitable area in free memory */
 684		low = max_t(unsigned long, crash_size, sclp.hsa_size);
 685		high = crash_base ? crash_base + crash_size : ULONG_MAX;
 686
 687		if (crash_base && crash_base < low) {
 688			pr_info("crashkernel reservation failed: %s\n",
 689				"crash_base too low");
 690			return;
 691		}
 692		low = crash_base ?: low;
 693		crash_base = memblock_phys_alloc_range(crash_size,
 694						       KEXEC_CRASH_MEM_ALIGN,
 695						       low, high);
 696	}
 697
 698	if (!crash_base) {
 699		pr_info("crashkernel reservation failed: %s\n",
 700			"no suitable area found");
 701		return;
 702	}
 703
 704	if (register_memory_notifier(&kdump_mem_nb)) {
 705		memblock_phys_free(crash_base, crash_size);
 706		return;
 707	}
 708
 709	if (!oldmem_data.start && MACHINE_IS_VM)
 710		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
 711	crashk_res.start = crash_base;
 712	crashk_res.end = crash_base + crash_size - 1;
 713	memblock_remove(crash_base, crash_size);
 714	pr_info("Reserving %lluMB of memory at %lluMB "
 715		"for crashkernel (System RAM: %luMB)\n",
 716		crash_size >> 20, crash_base >> 20,
 717		(unsigned long)memblock.memory.total_size >> 20);
 718	os_info_crashkernel_add(crash_base, crash_size);
 719#endif
 720}
 721
 722/*
 723 * Reserve the initrd from being used by memblock
 724 */
 725static void __init reserve_initrd(void)
 726{
 727#ifdef CONFIG_BLK_DEV_INITRD
 728	if (!initrd_data.start || !initrd_data.size)
 729		return;
 730	initrd_start = (unsigned long)__va(initrd_data.start);
 731	initrd_end = initrd_start + initrd_data.size;
 732	memblock_reserve(initrd_data.start, initrd_data.size);
 733#endif
 734}
 735
 736/*
 737 * Reserve the memory area used to pass the certificate lists
 738 */
 739static void __init reserve_certificate_list(void)
 740{
 741	if (ipl_cert_list_addr)
 742		memblock_reserve(ipl_cert_list_addr, ipl_cert_list_size);
 743}
 744
 745static void __init reserve_mem_detect_info(void)
 746{
 747	unsigned long start, size;
 748
 749	get_mem_detect_reserved(&start, &size);
 750	if (size)
 751		memblock_reserve(start, size);
 752}
 753
 754static void __init free_mem_detect_info(void)
 755{
 756	unsigned long start, size;
 757
 758	get_mem_detect_reserved(&start, &size);
 759	if (size)
 760		memblock_phys_free(start, size);
 761}
 762
 763static const char * __init get_mem_info_source(void)
 764{
 765	switch (mem_detect.info_source) {
 766	case MEM_DETECT_SCLP_STOR_INFO:
 767		return "sclp storage info";
 768	case MEM_DETECT_DIAG260:
 769		return "diag260";
 770	case MEM_DETECT_SCLP_READ_INFO:
 771		return "sclp read info";
 772	case MEM_DETECT_BIN_SEARCH:
 773		return "binary search";
 774	}
 775	return "none";
 776}
 777
 778static void __init memblock_add_mem_detect_info(void)
 779{
 780	unsigned long start, end;
 781	int i;
 782
 783	pr_debug("physmem info source: %s (%hhd)\n",
 784		 get_mem_info_source(), mem_detect.info_source);
 785	/* keep memblock lists close to the kernel */
 786	memblock_set_bottom_up(true);
 787	for_each_mem_detect_block(i, &start, &end) {
 788		memblock_add(start, end - start);
 789		memblock_physmem_add(start, end - start);
 790	}
 791	memblock_set_bottom_up(false);
 792	memblock_set_node(0, ULONG_MAX, &memblock.memory, 0);
 793}
 794
 795/*
 796 * Check for initrd being in usable memory
 797 */
 798static void __init check_initrd(void)
 799{
 800#ifdef CONFIG_BLK_DEV_INITRD
 801	if (initrd_data.start && initrd_data.size &&
 802	    !memblock_is_region_memory(initrd_data.start, initrd_data.size)) {
 803		pr_err("The initial RAM disk does not fit into the memory\n");
 804		memblock_phys_free(initrd_data.start, initrd_data.size);
 805		initrd_start = initrd_end = 0;
 806	}
 807#endif
 808}
 809
 810/*
 811 * Reserve memory used for lowcore/command line/kernel image.
 812 */
 813static void __init reserve_kernel(void)
 814{
 815	memblock_reserve(0, STARTUP_NORMAL_OFFSET);
 816	memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
 817	memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
 818	memblock_reserve(__amode31_base, __eamode31 - __samode31);
 819	memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
 820	memblock_reserve(__pa(_stext), _end - _stext);
 
 
 
 
 
 
 
 
 821}
 822
 823static void __init setup_memory(void)
 824{
 825	phys_addr_t start, end;
 826	u64 i;
 827
 828	/*
 829	 * Init storage key for present memory
 830	 */
 831	for_each_mem_range(i, &start, &end)
 832		storage_key_init_range(start, end);
 833
 834	psw_set_key(PAGE_DEFAULT_KEY);
 
 
 
 835}
 836
 837static void __init relocate_amode31_section(void)
 
 
 
 838{
 839	unsigned long amode31_size = __eamode31 - __samode31;
 840	long amode31_offset = __amode31_base - __samode31;
 841	long *ptr;
 842
 843	pr_info("Relocating AMODE31 section of size 0x%08lx\n", amode31_size);
 844
 845	/* Move original AMODE31 section to the new one */
 846	memmove((void *)__amode31_base, (void *)__samode31, amode31_size);
 847	/* Zero out the old AMODE31 section to catch invalid accesses within it */
 848	memset((void *)__samode31, 0, amode31_size);
 849
 850	/* Update all AMODE31 region references */
 851	for (ptr = _start_amode31_refs; ptr != _end_amode31_refs; ptr++)
 852		*ptr += amode31_offset;
 853}
 854
 855/* This must be called after AMODE31 relocation */
 856static void __init setup_cr(void)
 857{
 858	union ctlreg2 cr2;
 859	union ctlreg5 cr5;
 860	union ctlreg15 cr15;
 861
 862	__ctl_duct[1] = (unsigned long)__ctl_aste;
 863	__ctl_duct[2] = (unsigned long)__ctl_aste;
 864	__ctl_duct[4] = (unsigned long)__ctl_duald;
 865
 866	/* Update control registers CR2, CR5 and CR15 */
 867	__ctl_store(cr2.val, 2, 2);
 868	__ctl_store(cr5.val, 5, 5);
 869	__ctl_store(cr15.val, 15, 15);
 870	cr2.ducto = (unsigned long)__ctl_duct >> 6;
 871	cr5.pasteo = (unsigned long)__ctl_duct >> 6;
 872	cr15.lsea = (unsigned long)__ctl_linkage_stack >> 3;
 873	__ctl_load(cr2.val, 2, 2);
 874	__ctl_load(cr5.val, 5, 5);
 875	__ctl_load(cr15.val, 15, 15);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 876}
 
 877
 878/*
 879 * Add system information as device randomness
 880 */
 881static void __init setup_randomness(void)
 882{
 883	struct sysinfo_3_2_2 *vmms;
 884
 885	vmms = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 886	if (!vmms)
 887		panic("Failed to allocate memory for sysinfo structure\n");
 888	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 889		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
 890	memblock_free(vmms, PAGE_SIZE);
 891
 892	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
 893		static_branch_enable(&s390_arch_random_available);
 894}
 895
 896/*
 897 * Find the correct size for the task_struct. This depends on
 898 * the size of the struct fpu at the end of the thread_struct
 899 * which is embedded in the task_struct.
 900 */
 901static void __init setup_task_size(void)
 902{
 903	int task_size = sizeof(struct task_struct);
 904
 905	if (!MACHINE_HAS_VX) {
 906		task_size -= sizeof(__vector128) * __NUM_VXRS;
 907		task_size += sizeof(freg_t) * __NUM_FPRS;
 908	}
 909	arch_task_struct_size = task_size;
 910}
 911
 912/*
 913 * Issue diagnose 318 to set the control program name and
 914 * version codes.
 915 */
 916static void __init setup_control_program_code(void)
 917{
 918	union diag318_info diag318_info = {
 919		.cpnc = CPNC_LINUX,
 920		.cpvc = 0,
 921	};
 922
 923	if (!sclp.has_diag318)
 924		return;
 925
 926	diag_stat_inc(DIAG_STAT_X318);
 927	asm volatile("diag %0,0,0x318\n" : : "d" (diag318_info.val));
 928}
 929
 930/*
 931 * Print the component list from the IPL report
 932 */
 933static void __init log_component_list(void)
 934{
 935	struct ipl_rb_component_entry *ptr, *end;
 936	char *str;
 937
 938	if (!early_ipl_comp_list_addr)
 939		return;
 940	if (ipl_block.hdr.flags & IPL_PL_FLAG_SIPL)
 941		pr_info("Linux is running with Secure-IPL enabled\n");
 942	else
 943		pr_info("Linux is running with Secure-IPL disabled\n");
 944	ptr = (void *) early_ipl_comp_list_addr;
 945	end = (void *) ptr + early_ipl_comp_list_size;
 946	pr_info("The IPL report contains the following components:\n");
 947	while (ptr < end) {
 948		if (ptr->flags & IPL_RB_COMPONENT_FLAG_SIGNED) {
 949			if (ptr->flags & IPL_RB_COMPONENT_FLAG_VERIFIED)
 950				str = "signed, verified";
 951			else
 952				str = "signed, verification failed";
 953		} else {
 954			str = "not signed";
 955		}
 956		pr_info("%016llx - %016llx (%s)\n",
 957			ptr->addr, ptr->addr + ptr->len, str);
 958		ptr++;
 959	}
 960}
 961
 962/*
 963 * Setup function called from init/main.c just after the banner
 964 * was printed.
 965 */
 966
 967void __init setup_arch(char **cmdline_p)
 968{
 969        /*
 970         * print what head.S has found out about the machine
 971         */
 972	if (MACHINE_IS_VM)
 973		pr_info("Linux is running as a z/VM "
 974			"guest operating system in 64-bit mode\n");
 975	else if (MACHINE_IS_KVM)
 976		pr_info("Linux is running under KVM in 64-bit mode\n");
 977	else if (MACHINE_IS_LPAR)
 978		pr_info("Linux is running natively in 64-bit mode\n");
 979	else
 980		pr_info("Linux is running as a guest in 64-bit mode\n");
 981
 982	log_component_list();
 983
 984	/* Have one command line that is parsed and saved in /proc/cmdline */
 985	/* boot_command_line has been already set up in early.c */
 986	*cmdline_p = boot_command_line;
 987
 988        ROOT_DEV = Root_RAM0;
 989
 990	setup_initial_init_mm(_text, _etext, _edata, _end);
 
 
 
 
 991
 992	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 993		nospec_auto_detect();
 994
 995	jump_label_init();
 996	parse_early_param();
 997#ifdef CONFIG_CRASH_DUMP
 998	/* Deactivate elfcorehdr= kernel parameter */
 999	elfcorehdr_addr = ELFCORE_ADDR_MAX;
1000#endif
1001
1002	os_info_init();
1003	setup_ipl();
1004	setup_task_size();
1005	setup_control_program_code();
1006
1007	/* Do some memory reservations *before* memory is added to memblock */
 
 
1008	reserve_kernel();
1009	reserve_initrd();
1010	reserve_certificate_list();
1011	reserve_mem_detect_info();
1012	memblock_set_current_limit(ident_map_size);
1013	memblock_allow_resize();
1014
1015	/* Get information about *all* installed memory */
1016	memblock_add_mem_detect_info();
 
 
 
 
 
 
 
 
 
 
1017
1018	free_mem_detect_info();
1019	setup_memory_end();
1020	memblock_dump_all();
1021	setup_memory();
1022
1023	relocate_amode31_section();
1024	setup_cr();
1025	setup_uv();
1026	dma_contiguous_reserve(ident_map_size);
1027	vmcp_cma_reserve();
1028	if (MACHINE_HAS_EDAT2)
1029		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1030
1031	check_initrd();
1032	reserve_crashkernel();
1033#ifdef CONFIG_CRASH_DUMP
1034	/*
1035	 * Be aware that smp_save_dump_secondary_cpus() triggers a system reset.
1036	 * Therefore CPU and device initialization should be done afterwards.
1037	 */
1038	smp_save_dump_secondary_cpus();
1039#endif
1040
1041	setup_resources();
1042	setup_lowcore_dat_off();
1043	smp_fill_possible_mask();
1044	cpu_detect_mhz_feature();
1045        cpu_init();
1046	numa_setup();
1047	smp_detect_cpus();
1048	topology_init_early();
1049
1050	if (test_facility(193))
1051		static_branch_enable(&cpu_has_bear);
1052
1053	/*
1054	 * Create kernel page tables and switch to virtual addressing.
1055	 */
1056        paging_init();
1057	memcpy_real_init();
1058	/*
1059	 * After paging_init created the kernel page table, the new PSWs
1060	 * in lowcore can now run with DAT enabled.
1061	 */
1062	setup_lowcore_dat_on();
1063#ifdef CONFIG_CRASH_DUMP
1064	smp_save_dump_ipl_cpu();
1065#endif
1066
1067        /* Setup default console */
1068	conmode_default();
1069	set_preferred_console();
1070
1071	apply_alternative_instructions();
1072	if (IS_ENABLED(CONFIG_EXPOLINE))
1073		nospec_init_branches();
1074
1075	/* Setup zfcp/nvme dump support */
1076	setup_zfcpdump();
1077
1078	/* Add system specific data to the random pool */
1079	setup_randomness();
1080}
v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  S390 version
  4 *    Copyright IBM Corp. 1999, 2012
  5 *    Author(s): Hartmut Penner (hp@de.ibm.com),
  6 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
  7 *
  8 *  Derived from "arch/i386/kernel/setup.c"
  9 *    Copyright (C) 1995, Linus Torvalds
 10 */
 11
 12/*
 13 * This file handles the architecture-dependent parts of initialization
 14 */
 15
 16#define KMSG_COMPONENT "setup"
 17#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 18
 19#include <linux/errno.h>
 20#include <linux/export.h>
 21#include <linux/sched.h>
 22#include <linux/sched/task.h>
 23#include <linux/cpu.h>
 24#include <linux/kernel.h>
 25#include <linux/memblock.h>
 26#include <linux/mm.h>
 27#include <linux/stddef.h>
 28#include <linux/unistd.h>
 29#include <linux/ptrace.h>
 30#include <linux/random.h>
 31#include <linux/user.h>
 32#include <linux/tty.h>
 33#include <linux/ioport.h>
 34#include <linux/delay.h>
 35#include <linux/init.h>
 36#include <linux/initrd.h>
 37#include <linux/bootmem.h>
 38#include <linux/root_dev.h>
 39#include <linux/console.h>
 40#include <linux/kernel_stat.h>
 41#include <linux/dma-contiguous.h>
 42#include <linux/device.h>
 43#include <linux/notifier.h>
 44#include <linux/pfn.h>
 45#include <linux/ctype.h>
 46#include <linux/reboot.h>
 47#include <linux/topology.h>
 48#include <linux/kexec.h>
 49#include <linux/crash_dump.h>
 50#include <linux/memory.h>
 51#include <linux/compat.h>
 
 
 
 52
 
 
 53#include <asm/ipl.h>
 54#include <asm/facility.h>
 55#include <asm/smp.h>
 56#include <asm/mmu_context.h>
 57#include <asm/cpcmd.h>
 58#include <asm/lowcore.h>
 59#include <asm/nmi.h>
 60#include <asm/irq.h>
 61#include <asm/page.h>
 62#include <asm/ptrace.h>
 63#include <asm/sections.h>
 64#include <asm/ebcdic.h>
 65#include <asm/diag.h>
 66#include <asm/os_info.h>
 67#include <asm/sclp.h>
 
 68#include <asm/sysinfo.h>
 69#include <asm/numa.h>
 70#include <asm/alternative.h>
 71#include <asm/nospec-branch.h>
 
 
 
 
 72#include "entry.h"
 73
 74/*
 75 * Machine setup..
 76 */
 77unsigned int console_mode = 0;
 78EXPORT_SYMBOL(console_mode);
 79
 80unsigned int console_devno = -1;
 81EXPORT_SYMBOL(console_devno);
 82
 83unsigned int console_irq = -1;
 84EXPORT_SYMBOL(console_irq);
 85
 86unsigned long elf_hwcap __read_mostly = 0;
 87char elf_platform[ELF_PLATFORM_SIZE];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 88
 89unsigned long int_hwcap = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 90
 91int __initdata memory_end_set;
 92unsigned long __initdata memory_end;
 93unsigned long __initdata max_physmem_end;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 94
 95unsigned long VMALLOC_START;
 96EXPORT_SYMBOL(VMALLOC_START);
 97
 98unsigned long VMALLOC_END;
 99EXPORT_SYMBOL(VMALLOC_END);
100
101struct page *vmemmap;
102EXPORT_SYMBOL(vmemmap);
 
103
104unsigned long MODULES_VADDR;
105unsigned long MODULES_END;
106
107/* An array with a pointer to the lowcore of every CPU. */
108struct lowcore *lowcore_ptr[NR_CPUS];
109EXPORT_SYMBOL(lowcore_ptr);
110
 
 
 
 
 
 
 
 
111/*
112 * This is set up by the setup-routine at boot-time
113 * for S390 need to find out, what we have to setup
114 * using address 0x10400 ...
115 */
116
117#include <asm/setup.h>
118
119/*
120 * condev= and conmode= setup parameter.
121 */
122
123static int __init condev_setup(char *str)
124{
125	int vdev;
126
127	vdev = simple_strtoul(str, &str, 0);
128	if (vdev >= 0 && vdev < 65536) {
129		console_devno = vdev;
130		console_irq = -1;
131	}
132	return 1;
133}
134
135__setup("condev=", condev_setup);
136
137static void __init set_preferred_console(void)
138{
139	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
140		add_preferred_console("ttyS", 0, NULL);
141	else if (CONSOLE_IS_3270)
142		add_preferred_console("tty3270", 0, NULL);
143	else if (CONSOLE_IS_VT220)
144		add_preferred_console("ttyS", 1, NULL);
145	else if (CONSOLE_IS_HVC)
146		add_preferred_console("hvc", 0, NULL);
147}
148
149static int __init conmode_setup(char *str)
150{
151#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
152	if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
153                SET_CONSOLE_SCLP;
154#endif
155#if defined(CONFIG_TN3215_CONSOLE)
156	if (strncmp(str, "3215", 5) == 0)
157		SET_CONSOLE_3215;
158#endif
159#if defined(CONFIG_TN3270_CONSOLE)
160	if (strncmp(str, "3270", 5) == 0)
161		SET_CONSOLE_3270;
162#endif
163	set_preferred_console();
164        return 1;
165}
166
167__setup("conmode=", conmode_setup);
168
169static void __init conmode_default(void)
170{
171	char query_buffer[1024];
172	char *ptr;
173
174        if (MACHINE_IS_VM) {
175		cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
176		console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
177		ptr = strstr(query_buffer, "SUBCHANNEL =");
178		console_irq = simple_strtoul(ptr + 13, NULL, 16);
179		cpcmd("QUERY TERM", query_buffer, 1024, NULL);
180		ptr = strstr(query_buffer, "CONMODE");
181		/*
182		 * Set the conmode to 3215 so that the device recognition 
183		 * will set the cu_type of the console to 3215. If the
184		 * conmode is 3270 and we don't set it back then both
185		 * 3215 and the 3270 driver will try to access the console
186		 * device (3215 as console and 3270 as normal tty).
187		 */
188		cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
189		if (ptr == NULL) {
190#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
191			SET_CONSOLE_SCLP;
192#endif
193			return;
194		}
195		if (strncmp(ptr + 8, "3270", 4) == 0) {
196#if defined(CONFIG_TN3270_CONSOLE)
197			SET_CONSOLE_3270;
198#elif defined(CONFIG_TN3215_CONSOLE)
199			SET_CONSOLE_3215;
200#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
201			SET_CONSOLE_SCLP;
202#endif
203		} else if (strncmp(ptr + 8, "3215", 4) == 0) {
204#if defined(CONFIG_TN3215_CONSOLE)
205			SET_CONSOLE_3215;
206#elif defined(CONFIG_TN3270_CONSOLE)
207			SET_CONSOLE_3270;
208#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
209			SET_CONSOLE_SCLP;
210#endif
211		}
212	} else if (MACHINE_IS_KVM) {
213		if (sclp.has_vt220 && IS_ENABLED(CONFIG_SCLP_VT220_CONSOLE))
214			SET_CONSOLE_VT220;
215		else if (sclp.has_linemode && IS_ENABLED(CONFIG_SCLP_CONSOLE))
216			SET_CONSOLE_SCLP;
217		else
218			SET_CONSOLE_HVC;
219	} else {
220#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
221		SET_CONSOLE_SCLP;
222#endif
223	}
224	if (IS_ENABLED(CONFIG_VT) && IS_ENABLED(CONFIG_DUMMY_CONSOLE))
225		conswitchp = &dummy_con;
226}
227
228#ifdef CONFIG_CRASH_DUMP
229static void __init setup_zfcpdump(void)
230{
231	if (ipl_info.type != IPL_TYPE_FCP_DUMP)
232		return;
233	if (OLDMEM_BASE)
234		return;
235	strcat(boot_command_line, " cio_ignore=all,!ipldev,!condev");
236	console_loglevel = 2;
237}
238#else
239static inline void setup_zfcpdump(void) {}
240#endif /* CONFIG_CRASH_DUMP */
241
242 /*
243 * Reboot, halt and power_off stubs. They just call _machine_restart,
244 * _machine_halt or _machine_power_off. 
245 */
246
247void machine_restart(char *command)
248{
249	if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
250		/*
251		 * Only unblank the console if we are called in enabled
252		 * context or a bust_spinlocks cleared the way for us.
253		 */
254		console_unblank();
255	_machine_restart(command);
256}
257
258void machine_halt(void)
259{
260	if (!in_interrupt() || oops_in_progress)
261		/*
262		 * Only unblank the console if we are called in enabled
263		 * context or a bust_spinlocks cleared the way for us.
264		 */
265		console_unblank();
266	_machine_halt();
267}
268
269void machine_power_off(void)
270{
271	if (!in_interrupt() || oops_in_progress)
272		/*
273		 * Only unblank the console if we are called in enabled
274		 * context or a bust_spinlocks cleared the way for us.
275		 */
276		console_unblank();
277	_machine_power_off();
278}
279
280/*
281 * Dummy power off function.
282 */
283void (*pm_power_off)(void) = machine_power_off;
284EXPORT_SYMBOL_GPL(pm_power_off);
285
286static int __init early_parse_mem(char *p)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
287{
288	memory_end = memparse(p, &p);
289	memory_end &= PAGE_MASK;
290	memory_end_set = 1;
291	return 0;
 
292}
293early_param("mem", early_parse_mem);
294
295static int __init parse_vmalloc(char *arg)
296{
297	if (!arg)
298		return -EINVAL;
299	VMALLOC_END = (memparse(arg, &arg) + PAGE_SIZE - 1) & PAGE_MASK;
 
 
 
300	return 0;
301}
302early_param("vmalloc", parse_vmalloc);
303
304void *restart_stack __section(.data);
 
 
305
306static void __init setup_lowcore(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
307{
308	struct lowcore *lc;
 
 
 
 
 
 
309
310	/*
311	 * Setup lowcore for boot cpu
312	 */
313	BUILD_BUG_ON(sizeof(struct lowcore) != LC_PAGES * PAGE_SIZE);
314	lc = memblock_virt_alloc_low(sizeof(*lc), sizeof(*lc));
 
 
 
 
315	lc->restart_psw.mask = PSW_KERNEL_BITS;
316	lc->restart_psw.addr = (unsigned long) restart_int_handler;
317	lc->external_new_psw.mask = PSW_KERNEL_BITS |
318		PSW_MASK_DAT | PSW_MASK_MCHECK;
319	lc->external_new_psw.addr = (unsigned long) ext_int_handler;
320	lc->svc_new_psw.mask = PSW_KERNEL_BITS |
321		PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK;
322	lc->svc_new_psw.addr = (unsigned long) system_call;
323	lc->program_new_psw.mask = PSW_KERNEL_BITS |
324		PSW_MASK_DAT | PSW_MASK_MCHECK;
325	lc->program_new_psw.addr = (unsigned long) pgm_check_handler;
326	lc->mcck_new_psw.mask = PSW_KERNEL_BITS;
327	lc->mcck_new_psw.addr = (unsigned long) mcck_int_handler;
328	lc->io_new_psw.mask = PSW_KERNEL_BITS |
329		PSW_MASK_DAT | PSW_MASK_MCHECK;
330	lc->io_new_psw.addr = (unsigned long) io_int_handler;
331	lc->clock_comparator = clock_comparator_max;
332	lc->kernel_stack = ((unsigned long) &init_thread_union)
333		+ THREAD_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
334	lc->async_stack = (unsigned long)
335		memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE)
336		+ ASYNC_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
337	lc->panic_stack = (unsigned long)
338		memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE)
339		+ PAGE_SIZE - STACK_FRAME_OVERHEAD - sizeof(struct pt_regs);
340	lc->current_task = (unsigned long)&init_task;
341	lc->lpp = LPP_MAGIC;
342	lc->machine_flags = S390_lowcore.machine_flags;
343	lc->preempt_count = S390_lowcore.preempt_count;
344	lc->stfl_fac_list = S390_lowcore.stfl_fac_list;
345	memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list,
346	       sizeof(lc->stfle_fac_list));
347	memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list,
348	       sizeof(lc->alt_stfle_fac_list));
349	nmi_alloc_boot_cpu(lc);
350	vdso_alloc_boot_cpu(lc);
351	lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
352	lc->async_enter_timer = S390_lowcore.async_enter_timer;
353	lc->exit_timer = S390_lowcore.exit_timer;
354	lc->user_timer = S390_lowcore.user_timer;
355	lc->system_timer = S390_lowcore.system_timer;
356	lc->steal_timer = S390_lowcore.steal_timer;
357	lc->last_update_timer = S390_lowcore.last_update_timer;
358	lc->last_update_clock = S390_lowcore.last_update_clock;
359
360	restart_stack = memblock_virt_alloc(ASYNC_SIZE, ASYNC_SIZE);
361	restart_stack += ASYNC_SIZE;
 
 
 
 
 
 
 
362
363	/*
364	 * Set up PSW restart to call ipl.c:do_restart(). Copy the relevant
365	 * restart data to the absolute zero lowcore. This is necessary if
366	 * PSW restart is done on an offline CPU that has lowcore zero.
367	 */
368	lc->restart_stack = (unsigned long) restart_stack;
369	lc->restart_fn = (unsigned long) do_restart;
370	lc->restart_data = 0;
371	lc->restart_source = -1UL;
372
373	/* Setup absolute zero lowcore */
374	mem_assign_absolute(S390_lowcore.restart_stack, lc->restart_stack);
375	mem_assign_absolute(S390_lowcore.restart_fn, lc->restart_fn);
376	mem_assign_absolute(S390_lowcore.restart_data, lc->restart_data);
377	mem_assign_absolute(S390_lowcore.restart_source, lc->restart_source);
378	mem_assign_absolute(S390_lowcore.restart_psw, lc->restart_psw);
 
 
 
 
 
 
 
 
379
380#ifdef CONFIG_SMP
381	lc->spinlock_lockval = arch_spin_lockval(0);
382	lc->spinlock_index = 0;
383	arch_spin_lock_setup(0);
384#endif
385	lc->br_r1_trampoline = 0x07f1;	/* br %r1 */
 
386
387	set_prefix((u32)(unsigned long) lc);
388	lowcore_ptr[0] = lc;
389}
390
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
391static struct resource code_resource = {
392	.name  = "Kernel code",
393	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
394};
395
396static struct resource data_resource = {
397	.name = "Kernel data",
398	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
399};
400
401static struct resource bss_resource = {
402	.name = "Kernel bss",
403	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
404};
405
406static struct resource __initdata *standard_resources[] = {
407	&code_resource,
408	&data_resource,
409	&bss_resource,
410};
411
412static void __init setup_resources(void)
413{
414	struct resource *res, *std_res, *sub_res;
415	struct memblock_region *reg;
416	int j;
 
417
418	code_resource.start = (unsigned long) _text;
419	code_resource.end = (unsigned long) _etext - 1;
420	data_resource.start = (unsigned long) _etext;
421	data_resource.end = (unsigned long) _edata - 1;
422	bss_resource.start = (unsigned long) __bss_start;
423	bss_resource.end = (unsigned long) __bss_stop - 1;
424
425	for_each_memblock(memory, reg) {
426		res = memblock_virt_alloc(sizeof(*res), 8);
 
 
 
427		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
428
429		res->name = "System RAM";
430		res->start = reg->base;
431		res->end = reg->base + reg->size - 1;
 
 
 
 
 
432		request_resource(&iomem_resource, res);
433
434		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
435			std_res = standard_resources[j];
436			if (std_res->start < res->start ||
437			    std_res->start > res->end)
438				continue;
439			if (std_res->end > res->end) {
440				sub_res = memblock_virt_alloc(sizeof(*sub_res), 8);
 
 
 
441				*sub_res = *std_res;
442				sub_res->end = res->end;
443				std_res->start = res->end + 1;
444				request_resource(res, sub_res);
445			} else {
446				request_resource(res, std_res);
447			}
448		}
449	}
450#ifdef CONFIG_CRASH_DUMP
451	/*
452	 * Re-add removed crash kernel memory as reserved memory. This makes
453	 * sure it will be mapped with the identity mapping and struct pages
454	 * will be created, so it can be resized later on.
455	 * However add it later since the crash kernel resource should not be
456	 * part of the System RAM resource.
457	 */
458	if (crashk_res.end) {
459		memblock_add_node(crashk_res.start, resource_size(&crashk_res), 0);
 
460		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
461		insert_resource(&iomem_resource, &crashk_res);
462	}
463#endif
464}
465
466static void __init setup_memory_end(void)
467{
468	unsigned long vmax, vmalloc_size, tmp;
469
470	/* Choose kernel address space layout: 2, 3, or 4 levels. */
471	vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
472	tmp = (memory_end ?: max_physmem_end) / PAGE_SIZE;
473	tmp = tmp * (sizeof(struct page) + PAGE_SIZE);
474	if (tmp + vmalloc_size + MODULES_LEN <= _REGION2_SIZE)
475		vmax = _REGION2_SIZE; /* 3-level kernel page table */
476	else
477		vmax = _REGION1_SIZE; /* 4-level kernel page table */
478	/* module area is at the end of the kernel address space. */
479	MODULES_END = vmax;
480	MODULES_VADDR = MODULES_END - MODULES_LEN;
481	VMALLOC_END = MODULES_VADDR;
482	VMALLOC_START = vmax - vmalloc_size;
483
484	/* Split remaining virtual space between 1:1 mapping & vmemmap array */
485	tmp = VMALLOC_START / (PAGE_SIZE + sizeof(struct page));
486	/* vmemmap contains a multiple of PAGES_PER_SECTION struct pages */
487	tmp = SECTION_ALIGN_UP(tmp);
488	tmp = VMALLOC_START - tmp * sizeof(struct page);
489	tmp &= ~((vmax >> 11) - 1);	/* align to page table level */
490	tmp = min(tmp, 1UL << MAX_PHYSMEM_BITS);
491	vmemmap = (struct page *) tmp;
492
493	/* Take care that memory_end is set and <= vmemmap */
494	memory_end = min(memory_end ?: max_physmem_end, tmp);
495	max_pfn = max_low_pfn = PFN_DOWN(memory_end);
496	memblock_remove(memory_end, ULONG_MAX);
497
498	pr_notice("The maximum memory size is %luMB\n", memory_end >> 20);
499}
500
501#ifdef CONFIG_CRASH_DUMP
502
503/*
504 * When kdump is enabled, we have to ensure that no memory from
505 * the area [0 - crashkernel memory size] and
506 * [crashk_res.start - crashk_res.end] is set offline.
 
507 */
508static int kdump_mem_notifier(struct notifier_block *nb,
509			      unsigned long action, void *data)
510{
511	struct memory_notify *arg = data;
512
513	if (action != MEM_GOING_OFFLINE)
514		return NOTIFY_OK;
515	if (arg->start_pfn < PFN_DOWN(resource_size(&crashk_res)))
516		return NOTIFY_BAD;
517	if (arg->start_pfn > PFN_DOWN(crashk_res.end))
518		return NOTIFY_OK;
519	if (arg->start_pfn + arg->nr_pages - 1 < PFN_DOWN(crashk_res.start))
520		return NOTIFY_OK;
521	return NOTIFY_BAD;
522}
523
524static struct notifier_block kdump_mem_nb = {
525	.notifier_call = kdump_mem_notifier,
526};
527
528#endif
529
530/*
531 * Make sure that the area behind memory_end is protected
532 */
533static void reserve_memory_end(void)
534{
535#ifdef CONFIG_CRASH_DUMP
536	if (ipl_info.type == IPL_TYPE_FCP_DUMP &&
537	    !OLDMEM_BASE && sclp.hsa_size) {
538		memory_end = sclp.hsa_size;
539		memory_end &= PAGE_MASK;
540		memory_end_set = 1;
541	}
542#endif
543	if (!memory_end_set)
544		return;
545	memblock_reserve(memory_end, ULONG_MAX);
546}
547
548/*
549 * Make sure that oldmem, where the dump is stored, is protected
550 */
551static void reserve_oldmem(void)
552{
553#ifdef CONFIG_CRASH_DUMP
554	if (OLDMEM_BASE)
555		/* Forget all memory above the running kdump system */
556		memblock_reserve(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
557#endif
558}
559
560/*
561 * Make sure that oldmem, where the dump is stored, is protected
562 */
563static void remove_oldmem(void)
564{
565#ifdef CONFIG_CRASH_DUMP
566	if (OLDMEM_BASE)
567		/* Forget all memory above the running kdump system */
568		memblock_remove(OLDMEM_SIZE, (phys_addr_t)ULONG_MAX);
569#endif
570}
571
572/*
573 * Reserve memory for kdump kernel to be loaded with kexec
574 */
575static void __init reserve_crashkernel(void)
576{
577#ifdef CONFIG_CRASH_DUMP
578	unsigned long long crash_base, crash_size;
579	phys_addr_t low, high;
580	int rc;
581
582	rc = parse_crashkernel(boot_command_line, memory_end, &crash_size,
583			       &crash_base);
584
585	crash_base = ALIGN(crash_base, KEXEC_CRASH_MEM_ALIGN);
586	crash_size = ALIGN(crash_size, KEXEC_CRASH_MEM_ALIGN);
587	if (rc || crash_size == 0)
588		return;
589
590	if (memblock.memory.regions[0].size < crash_size) {
591		pr_info("crashkernel reservation failed: %s\n",
592			"first memory chunk must be at least crashkernel size");
593		return;
594	}
595
596	low = crash_base ?: OLDMEM_BASE;
597	high = low + crash_size;
598	if (low >= OLDMEM_BASE && high <= OLDMEM_BASE + OLDMEM_SIZE) {
599		/* The crashkernel fits into OLDMEM, reuse OLDMEM */
600		crash_base = low;
601	} else {
602		/* Find suitable area in free memory */
603		low = max_t(unsigned long, crash_size, sclp.hsa_size);
604		high = crash_base ? crash_base + crash_size : ULONG_MAX;
605
606		if (crash_base && crash_base < low) {
607			pr_info("crashkernel reservation failed: %s\n",
608				"crash_base too low");
609			return;
610		}
611		low = crash_base ?: low;
612		crash_base = memblock_find_in_range(low, high, crash_size,
613						    KEXEC_CRASH_MEM_ALIGN);
 
614	}
615
616	if (!crash_base) {
617		pr_info("crashkernel reservation failed: %s\n",
618			"no suitable area found");
619		return;
620	}
621
622	if (register_memory_notifier(&kdump_mem_nb))
 
623		return;
 
624
625	if (!OLDMEM_BASE && MACHINE_IS_VM)
626		diag10_range(PFN_DOWN(crash_base), PFN_DOWN(crash_size));
627	crashk_res.start = crash_base;
628	crashk_res.end = crash_base + crash_size - 1;
629	memblock_remove(crash_base, crash_size);
630	pr_info("Reserving %lluMB of memory at %lluMB "
631		"for crashkernel (System RAM: %luMB)\n",
632		crash_size >> 20, crash_base >> 20,
633		(unsigned long)memblock.memory.total_size >> 20);
634	os_info_crashkernel_add(crash_base, crash_size);
635#endif
636}
637
638/*
639 * Reserve the initrd from being used by memblock
640 */
641static void __init reserve_initrd(void)
642{
643#ifdef CONFIG_BLK_DEV_INITRD
644	if (!INITRD_START || !INITRD_SIZE)
645		return;
646	initrd_start = INITRD_START;
647	initrd_end = initrd_start + INITRD_SIZE;
648	memblock_reserve(INITRD_START, INITRD_SIZE);
649#endif
650}
651
652/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
653 * Check for initrd being in usable memory
654 */
655static void __init check_initrd(void)
656{
657#ifdef CONFIG_BLK_DEV_INITRD
658	if (INITRD_START && INITRD_SIZE &&
659	    !memblock_is_region_memory(INITRD_START, INITRD_SIZE)) {
660		pr_err("The initial RAM disk does not fit into the memory\n");
661		memblock_free(INITRD_START, INITRD_SIZE);
662		initrd_start = initrd_end = 0;
663	}
664#endif
665}
666
667/*
668 * Reserve memory used for lowcore/command line/kernel image.
669 */
670static void __init reserve_kernel(void)
671{
672	unsigned long start_pfn = PFN_UP(__pa(_end));
673
674#ifdef CONFIG_DMA_API_DEBUG
675	/*
676	 * DMA_API_DEBUG code stumbles over addresses from the
677	 * range [_ehead, _stext]. Mark the memory as reserved
678	 * so it is not used for CONFIG_DMA_API_DEBUG=y.
679	 */
680	memblock_reserve(0, PFN_PHYS(start_pfn));
681#else
682	memblock_reserve(0, (unsigned long)_ehead);
683	memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn)
684			 - (unsigned long)_stext);
685#endif
686}
687
688static void __init setup_memory(void)
689{
690	struct memblock_region *reg;
 
691
692	/*
693	 * Init storage key for present memory
694	 */
695	for_each_memblock(memory, reg) {
696		storage_key_init_range(reg->base, reg->base + reg->size);
697	}
698	psw_set_key(PAGE_DEFAULT_KEY);
699
700	/* Only cosmetics */
701	memblock_enforce_memory_limit(memblock_end_of_DRAM());
702}
703
704/*
705 * Setup hardware capabilities.
706 */
707static int __init setup_hwcaps(void)
708{
709	static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
710	struct cpuid cpu_id;
711	int i;
712
713	/*
714	 * The store facility list bits numbers as found in the principles
715	 * of operation are numbered with bit 1UL<<31 as number 0 to
716	 * bit 1UL<<0 as number 31.
717	 *   Bit 0: instructions named N3, "backported" to esa-mode
718	 *   Bit 2: z/Architecture mode is active
719	 *   Bit 7: the store-facility-list-extended facility is installed
720	 *   Bit 17: the message-security assist is installed
721	 *   Bit 19: the long-displacement facility is installed
722	 *   Bit 21: the extended-immediate facility is installed
723	 *   Bit 22: extended-translation facility 3 is installed
724	 *   Bit 30: extended-translation facility 3 enhancement facility
725	 * These get translated to:
726	 *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
727	 *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
728	 *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
729	 *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
730	 */
731	for (i = 0; i < 6; i++)
732		if (test_facility(stfl_bits[i]))
733			elf_hwcap |= 1UL << i;
734
735	if (test_facility(22) && test_facility(30))
736		elf_hwcap |= HWCAP_S390_ETF3EH;
737
738	/*
739	 * Check for additional facilities with store-facility-list-extended.
740	 * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
741	 * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
742	 * as stored by stfl, bits 32-xxx contain additional facilities.
743	 * How many facility words are stored depends on the number of
744	 * doublewords passed to the instruction. The additional facilities
745	 * are:
746	 *   Bit 42: decimal floating point facility is installed
747	 *   Bit 44: perform floating point operation facility is installed
748	 * translated to:
749	 *   HWCAP_S390_DFP bit 6 (42 && 44).
750	 */
751	if ((elf_hwcap & (1UL << 2)) && test_facility(42) && test_facility(44))
752		elf_hwcap |= HWCAP_S390_DFP;
753
754	/*
755	 * Huge page support HWCAP_S390_HPAGE is bit 7.
756	 */
757	if (MACHINE_HAS_EDAT1)
758		elf_hwcap |= HWCAP_S390_HPAGE;
759
760	/*
761	 * 64-bit register support for 31-bit processes
762	 * HWCAP_S390_HIGH_GPRS is bit 9.
763	 */
764	elf_hwcap |= HWCAP_S390_HIGH_GPRS;
765
766	/*
767	 * Transactional execution support HWCAP_S390_TE is bit 10.
768	 */
769	if (MACHINE_HAS_TE)
770		elf_hwcap |= HWCAP_S390_TE;
771
772	/*
773	 * Vector extension HWCAP_S390_VXRS is bit 11. The Vector extension
774	 * can be disabled with the "novx" parameter. Use MACHINE_HAS_VX
775	 * instead of facility bit 129.
776	 */
777	if (MACHINE_HAS_VX) {
778		elf_hwcap |= HWCAP_S390_VXRS;
779		if (test_facility(134))
780			elf_hwcap |= HWCAP_S390_VXRS_EXT;
781		if (test_facility(135))
782			elf_hwcap |= HWCAP_S390_VXRS_BCD;
783	}
784
785	/*
786	 * Guarded storage support HWCAP_S390_GS is bit 12.
787	 */
788	if (MACHINE_HAS_GS)
789		elf_hwcap |= HWCAP_S390_GS;
790
791	get_cpu_id(&cpu_id);
792	add_device_randomness(&cpu_id, sizeof(cpu_id));
793	switch (cpu_id.machine) {
794	case 0x2064:
795	case 0x2066:
796	default:	/* Use "z900" as default for 64 bit kernels. */
797		strcpy(elf_platform, "z900");
798		break;
799	case 0x2084:
800	case 0x2086:
801		strcpy(elf_platform, "z990");
802		break;
803	case 0x2094:
804	case 0x2096:
805		strcpy(elf_platform, "z9-109");
806		break;
807	case 0x2097:
808	case 0x2098:
809		strcpy(elf_platform, "z10");
810		break;
811	case 0x2817:
812	case 0x2818:
813		strcpy(elf_platform, "z196");
814		break;
815	case 0x2827:
816	case 0x2828:
817		strcpy(elf_platform, "zEC12");
818		break;
819	case 0x2964:
820	case 0x2965:
821		strcpy(elf_platform, "z13");
822		break;
823	case 0x3906:
824	case 0x3907:
825		strcpy(elf_platform, "z14");
826		break;
827	}
828
829	/*
830	 * Virtualization support HWCAP_INT_SIE is bit 0.
831	 */
832	if (sclp.has_sief2)
833		int_hwcap |= HWCAP_INT_SIE;
834
835	return 0;
836}
837arch_initcall(setup_hwcaps);
838
839/*
840 * Add system information as device randomness
841 */
842static void __init setup_randomness(void)
843{
844	struct sysinfo_3_2_2 *vmms;
845
846	vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 
 
847	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
848		add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count);
849	memblock_free((unsigned long) vmms, PAGE_SIZE);
 
 
 
850}
851
852/*
853 * Find the correct size for the task_struct. This depends on
854 * the size of the struct fpu at the end of the thread_struct
855 * which is embedded in the task_struct.
856 */
857static void __init setup_task_size(void)
858{
859	int task_size = sizeof(struct task_struct);
860
861	if (!MACHINE_HAS_VX) {
862		task_size -= sizeof(__vector128) * __NUM_VXRS;
863		task_size += sizeof(freg_t) * __NUM_FPRS;
864	}
865	arch_task_struct_size = task_size;
866}
867
868/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
869 * Setup function called from init/main.c just after the banner
870 * was printed.
871 */
872
873void __init setup_arch(char **cmdline_p)
874{
875        /*
876         * print what head.S has found out about the machine
877         */
878	if (MACHINE_IS_VM)
879		pr_info("Linux is running as a z/VM "
880			"guest operating system in 64-bit mode\n");
881	else if (MACHINE_IS_KVM)
882		pr_info("Linux is running under KVM in 64-bit mode\n");
883	else if (MACHINE_IS_LPAR)
884		pr_info("Linux is running natively in 64-bit mode\n");
 
 
 
 
885
886	/* Have one command line that is parsed and saved in /proc/cmdline */
887	/* boot_command_line has been already set up in early.c */
888	*cmdline_p = boot_command_line;
889
890        ROOT_DEV = Root_RAM0;
891
892	/* Is init_mm really needed? */
893	init_mm.start_code = PAGE_OFFSET;
894	init_mm.end_code = (unsigned long) _etext;
895	init_mm.end_data = (unsigned long) _edata;
896	init_mm.brk = (unsigned long) _end;
897
898	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
899		nospec_auto_detect();
900
 
901	parse_early_param();
902#ifdef CONFIG_CRASH_DUMP
903	/* Deactivate elfcorehdr= kernel parameter */
904	elfcorehdr_addr = ELFCORE_ADDR_MAX;
905#endif
906
907	os_info_init();
908	setup_ipl();
909	setup_task_size();
 
910
911	/* Do some memory reservations *before* memory is added to memblock */
912	reserve_memory_end();
913	reserve_oldmem();
914	reserve_kernel();
915	reserve_initrd();
 
 
 
916	memblock_allow_resize();
917
918	/* Get information about *all* installed memory */
919	detect_memory_memblock();
920
921	remove_oldmem();
922
923	/*
924	 * Make sure all chunks are MAX_ORDER aligned so we don't need the
925	 * extra checks that HOLES_IN_ZONE would require.
926	 *
927	 * Is this still required?
928	 */
929	memblock_trim_memory(1UL << (MAX_ORDER - 1 + PAGE_SHIFT));
930
 
931	setup_memory_end();
 
932	setup_memory();
933	dma_contiguous_reserve(memory_end);
 
 
 
 
934	vmcp_cma_reserve();
 
 
935
936	check_initrd();
937	reserve_crashkernel();
938#ifdef CONFIG_CRASH_DUMP
939	/*
940	 * Be aware that smp_save_dump_cpus() triggers a system reset.
941	 * Therefore CPU and device initialization should be done afterwards.
942	 */
943	smp_save_dump_cpus();
944#endif
945
946	setup_resources();
947	setup_lowcore();
948	smp_fill_possible_mask();
949	cpu_detect_mhz_feature();
950        cpu_init();
951	numa_setup();
952	smp_detect_cpus();
953	topology_init_early();
954
 
 
 
955	/*
956	 * Create kernel page tables and switch to virtual addressing.
957	 */
958        paging_init();
 
 
 
 
 
 
 
 
 
959
960        /* Setup default console */
961	conmode_default();
962	set_preferred_console();
963
964	apply_alternative_instructions();
965	if (IS_ENABLED(CONFIG_EXPOLINE))
966		nospec_init_branches();
967
968	/* Setup zfcpdump support */
969	setup_zfcpdump();
970
971	/* Add system specific data to the random pool */
972	setup_randomness();
973}