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v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Common boot and setup code for both 32-bit and 64-bit.
   4 * Extracted from arch/powerpc/kernel/setup_64.c.
   5 *
   6 * Copyright (C) 2001 PPC64 Team, IBM Corp
   7 */
   8
   9#undef DEBUG
  10
  11#include <linux/export.h>
  12#include <linux/panic_notifier.h>
  13#include <linux/string.h>
  14#include <linux/sched.h>
  15#include <linux/init.h>
  16#include <linux/kernel.h>
  17#include <linux/reboot.h>
  18#include <linux/delay.h>
  19#include <linux/initrd.h>
  20#include <linux/platform_device.h>
  21#include <linux/printk.h>
  22#include <linux/seq_file.h>
  23#include <linux/ioport.h>
  24#include <linux/console.h>
  25#include <linux/screen_info.h>
  26#include <linux/root_dev.h>
  27#include <linux/cpu.h>
  28#include <linux/unistd.h>
  29#include <linux/seq_buf.h>
  30#include <linux/serial.h>
  31#include <linux/serial_8250.h>
  32#include <linux/percpu.h>
  33#include <linux/memblock.h>
  34#include <linux/of_irq.h>
  35#include <linux/of_fdt.h>
  36#include <linux/of_platform.h>
  37#include <linux/hugetlb.h>
  38#include <linux/pgtable.h>
  39#include <asm/io.h>
  40#include <asm/paca.h>
  41#include <asm/processor.h>
  42#include <asm/vdso_datapage.h>
  43#include <asm/smp.h>
  44#include <asm/elf.h>
  45#include <asm/machdep.h>
  46#include <asm/time.h>
  47#include <asm/cputable.h>
  48#include <asm/sections.h>
  49#include <asm/firmware.h>
  50#include <asm/btext.h>
  51#include <asm/nvram.h>
  52#include <asm/setup.h>
  53#include <asm/rtas.h>
  54#include <asm/iommu.h>
  55#include <asm/serial.h>
  56#include <asm/cache.h>
  57#include <asm/page.h>
  58#include <asm/mmu.h>
  59#include <asm/xmon.h>
  60#include <asm/cputhreads.h>
  61#include <mm/mmu_decl.h>
  62#include <asm/archrandom.h>
  63#include <asm/fadump.h>
  64#include <asm/udbg.h>
  65#include <asm/hugetlb.h>
  66#include <asm/livepatch.h>
  67#include <asm/mmu_context.h>
  68#include <asm/cpu_has_feature.h>
  69#include <asm/kasan.h>
  70#include <asm/mce.h>
  71
  72#include "setup.h"
  73
  74#ifdef DEBUG
  75#define DBG(fmt...) udbg_printf(fmt)
  76#else
  77#define DBG(fmt...)
  78#endif
  79
  80/* The main machine-dep calls structure
  81 */
  82struct machdep_calls ppc_md;
  83EXPORT_SYMBOL(ppc_md);
  84struct machdep_calls *machine_id;
  85EXPORT_SYMBOL(machine_id);
  86
  87int boot_cpuid = -1;
  88EXPORT_SYMBOL_GPL(boot_cpuid);
 
 
 
 
 
  89
  90/*
  91 * These are used in binfmt_elf.c to put aux entries on the stack
  92 * for each elf executable being started.
  93 */
  94int dcache_bsize;
  95int icache_bsize;
  96
  97/*
  98 * This still seems to be needed... -- paulus
  99 */ 
 100struct screen_info screen_info = {
 101	.orig_x = 0,
 102	.orig_y = 25,
 103	.orig_video_cols = 80,
 104	.orig_video_lines = 25,
 105	.orig_video_isVGA = 1,
 106	.orig_video_points = 16
 107};
 108#if defined(CONFIG_FB_VGA16_MODULE)
 109EXPORT_SYMBOL(screen_info);
 110#endif
 111
 112/* Variables required to store legacy IO irq routing */
 113int of_i8042_kbd_irq;
 114EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
 115int of_i8042_aux_irq;
 116EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
 117
 118#ifdef __DO_IRQ_CANON
 119/* XXX should go elsewhere eventually */
 120int ppc_do_canonicalize_irqs;
 121EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
 122#endif
 123
 124#ifdef CONFIG_CRASH_CORE
 125/* This keeps a track of which one is the crashing cpu. */
 126int crashing_cpu = -1;
 127#endif
 128
 129/* also used by kexec */
 130void machine_shutdown(void)
 131{
 132	/*
 133	 * if fadump is active, cleanup the fadump registration before we
 134	 * shutdown.
 135	 */
 136	fadump_cleanup();
 137
 138	if (ppc_md.machine_shutdown)
 139		ppc_md.machine_shutdown();
 140}
 141
 142static void machine_hang(void)
 143{
 144	pr_emerg("System Halted, OK to turn off power\n");
 145	local_irq_disable();
 146	while (1)
 147		;
 148}
 149
 150void machine_restart(char *cmd)
 151{
 152	machine_shutdown();
 153	if (ppc_md.restart)
 154		ppc_md.restart(cmd);
 155
 156	smp_send_stop();
 157
 158	do_kernel_restart(cmd);
 159	mdelay(1000);
 160
 161	machine_hang();
 162}
 163
 164void machine_power_off(void)
 165{
 166	machine_shutdown();
 167	do_kernel_power_off();
 168	smp_send_stop();
 169	machine_hang();
 170}
 171/* Used by the G5 thermal driver */
 172EXPORT_SYMBOL_GPL(machine_power_off);
 173
 174void (*pm_power_off)(void);
 175EXPORT_SYMBOL_GPL(pm_power_off);
 176
 177size_t __must_check arch_get_random_seed_longs(unsigned long *v, size_t max_longs)
 178{
 179	if (max_longs && ppc_md.get_random_seed && ppc_md.get_random_seed(v))
 180		return 1;
 181	return 0;
 182}
 183EXPORT_SYMBOL(arch_get_random_seed_longs);
 184
 185void machine_halt(void)
 186{
 187	machine_shutdown();
 188	if (ppc_md.halt)
 189		ppc_md.halt();
 190
 191	smp_send_stop();
 192	machine_hang();
 193}
 194
 195#ifdef CONFIG_SMP
 196DEFINE_PER_CPU(unsigned int, cpu_pvr);
 197#endif
 198
 199static void show_cpuinfo_summary(struct seq_file *m)
 200{
 201	struct device_node *root;
 202	const char *model = NULL;
 203	unsigned long bogosum = 0;
 204	int i;
 205
 206	if (IS_ENABLED(CONFIG_SMP) && IS_ENABLED(CONFIG_PPC32)) {
 207		for_each_online_cpu(i)
 208			bogosum += loops_per_jiffy;
 209		seq_printf(m, "total bogomips\t: %lu.%02lu\n",
 210			   bogosum / (500000 / HZ), bogosum / (5000 / HZ) % 100);
 211	}
 212	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
 213	if (ppc_md.name)
 214		seq_printf(m, "platform\t: %s\n", ppc_md.name);
 215	root = of_find_node_by_path("/");
 216	if (root)
 217		model = of_get_property(root, "model", NULL);
 218	if (model)
 219		seq_printf(m, "model\t\t: %s\n", model);
 220	of_node_put(root);
 221
 222	if (ppc_md.show_cpuinfo != NULL)
 223		ppc_md.show_cpuinfo(m);
 224
 225	/* Display the amount of memory */
 226	if (IS_ENABLED(CONFIG_PPC32))
 227		seq_printf(m, "Memory\t\t: %d MB\n",
 228			   (unsigned int)(total_memory / (1024 * 1024)));
 229}
 230
 231static int show_cpuinfo(struct seq_file *m, void *v)
 232{
 233	unsigned long cpu_id = (unsigned long)v - 1;
 234	unsigned int pvr;
 235	unsigned long proc_freq;
 236	unsigned short maj;
 237	unsigned short min;
 238
 239#ifdef CONFIG_SMP
 240	pvr = per_cpu(cpu_pvr, cpu_id);
 241#else
 242	pvr = mfspr(SPRN_PVR);
 243#endif
 244	maj = (pvr >> 8) & 0xFF;
 245	min = pvr & 0xFF;
 246
 247	seq_printf(m, "processor\t: %lu\ncpu\t\t: ", cpu_id);
 248
 249	if (cur_cpu_spec->pvr_mask && cur_cpu_spec->cpu_name)
 250		seq_puts(m, cur_cpu_spec->cpu_name);
 251	else
 252		seq_printf(m, "unknown (%08x)", pvr);
 253
 254	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 255		seq_puts(m, ", altivec supported");
 256
 257	seq_putc(m, '\n');
 258
 259#ifdef CONFIG_TAU
 260	if (cpu_has_feature(CPU_FTR_TAU)) {
 261		if (IS_ENABLED(CONFIG_TAU_AVERAGE)) {
 262			/* more straightforward, but potentially misleading */
 263			seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
 264				   cpu_temp(cpu_id));
 265		} else {
 266			/* show the actual temp sensor range */
 267			u32 temp;
 268			temp = cpu_temp_both(cpu_id);
 269			seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
 270				   temp & 0xff, temp >> 16);
 271		}
 272	}
 273#endif /* CONFIG_TAU */
 274
 275	/*
 276	 * Platforms that have variable clock rates, should implement
 277	 * the method ppc_md.get_proc_freq() that reports the clock
 278	 * rate of a given cpu. The rest can use ppc_proc_freq to
 279	 * report the clock rate that is same across all cpus.
 280	 */
 281	if (ppc_md.get_proc_freq)
 282		proc_freq = ppc_md.get_proc_freq(cpu_id);
 283	else
 284		proc_freq = ppc_proc_freq;
 285
 286	if (proc_freq)
 287		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
 288			   proc_freq / 1000000, proc_freq % 1000000);
 289
 290	/* If we are a Freescale core do a simple check so
 291	 * we don't have to keep adding cases in the future */
 292	if (PVR_VER(pvr) & 0x8000) {
 293		switch (PVR_VER(pvr)) {
 294		case 0x8000:	/* 7441/7450/7451, Voyager */
 295		case 0x8001:	/* 7445/7455, Apollo 6 */
 296		case 0x8002:	/* 7447/7457, Apollo 7 */
 297		case 0x8003:	/* 7447A, Apollo 7 PM */
 298		case 0x8004:	/* 7448, Apollo 8 */
 299		case 0x800c:	/* 7410, Nitro */
 300			maj = ((pvr >> 8) & 0xF);
 301			min = PVR_MIN(pvr);
 302			break;
 303		default:	/* e500/book-e */
 304			maj = PVR_MAJ(pvr);
 305			min = PVR_MIN(pvr);
 306			break;
 307		}
 308	} else {
 309		switch (PVR_VER(pvr)) {
 310			case 0x1008:	/* 740P/750P ?? */
 311				maj = ((pvr >> 8) & 0xFF) - 1;
 312				min = pvr & 0xFF;
 313				break;
 314			case 0x004e: /* POWER9 bits 12-15 give chip type */
 315			case 0x0080: /* POWER10 bit 12 gives SMT8/4 */
 316				maj = (pvr >> 8) & 0x0F;
 317				min = pvr & 0xFF;
 318				break;
 319			default:
 320				maj = (pvr >> 8) & 0xFF;
 321				min = pvr & 0xFF;
 322				break;
 323		}
 324	}
 325
 326	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
 327		   maj, min, PVR_VER(pvr), PVR_REV(pvr));
 328
 329	if (IS_ENABLED(CONFIG_PPC32))
 330		seq_printf(m, "bogomips\t: %lu.%02lu\n", loops_per_jiffy / (500000 / HZ),
 331			   (loops_per_jiffy / (5000 / HZ)) % 100);
 332
 333	seq_putc(m, '\n');
 334
 335	/* If this is the last cpu, print the summary */
 336	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
 337		show_cpuinfo_summary(m);
 338
 339	return 0;
 340}
 341
 342static void *c_start(struct seq_file *m, loff_t *pos)
 343{
 344	if (*pos == 0)	/* just in case, cpu 0 is not the first */
 345		*pos = cpumask_first(cpu_online_mask);
 346	else
 347		*pos = cpumask_next(*pos - 1, cpu_online_mask);
 348	if ((*pos) < nr_cpu_ids)
 349		return (void *)(unsigned long)(*pos + 1);
 350	return NULL;
 351}
 352
 353static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 354{
 355	(*pos)++;
 356	return c_start(m, pos);
 357}
 358
 359static void c_stop(struct seq_file *m, void *v)
 360{
 361}
 362
 363const struct seq_operations cpuinfo_op = {
 364	.start	= c_start,
 365	.next	= c_next,
 366	.stop	= c_stop,
 367	.show	= show_cpuinfo,
 368};
 369
 370void __init check_for_initrd(void)
 371{
 372#ifdef CONFIG_BLK_DEV_INITRD
 373	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
 374	    initrd_start, initrd_end);
 375
 376	/* If we were passed an initrd, set the ROOT_DEV properly if the values
 377	 * look sensible. If not, clear initrd reference.
 378	 */
 379	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
 380	    initrd_end > initrd_start)
 381		ROOT_DEV = Root_RAM0;
 382	else
 383		initrd_start = initrd_end = 0;
 384
 385	if (initrd_start)
 386		pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
 387
 388	DBG(" <- check_for_initrd()\n");
 389#endif /* CONFIG_BLK_DEV_INITRD */
 390}
 391
 392#ifdef CONFIG_SMP
 393
 394int threads_per_core, threads_per_subcore, threads_shift __read_mostly;
 395cpumask_t threads_core_mask __read_mostly;
 396EXPORT_SYMBOL_GPL(threads_per_core);
 397EXPORT_SYMBOL_GPL(threads_per_subcore);
 398EXPORT_SYMBOL_GPL(threads_shift);
 399EXPORT_SYMBOL_GPL(threads_core_mask);
 400
 401static void __init cpu_init_thread_core_maps(int tpc)
 402{
 403	int i;
 404
 405	threads_per_core = tpc;
 406	threads_per_subcore = tpc;
 407	cpumask_clear(&threads_core_mask);
 408
 409	/* This implementation only supports power of 2 number of threads
 410	 * for simplicity and performance
 411	 */
 412	threads_shift = ilog2(tpc);
 413	BUG_ON(tpc != (1 << threads_shift));
 414
 415	for (i = 0; i < tpc; i++)
 416		cpumask_set_cpu(i, &threads_core_mask);
 417
 418	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
 419	       tpc, tpc > 1 ? "s" : "");
 420	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
 421}
 422
 423
 424u32 *cpu_to_phys_id = NULL;
 425
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 426/**
 427 * setup_cpu_maps - initialize the following cpu maps:
 428 *                  cpu_possible_mask
 429 *                  cpu_present_mask
 430 *
 431 * Having the possible map set up early allows us to restrict allocations
 432 * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
 433 *
 434 * We do not initialize the online map here; cpus set their own bits in
 435 * cpu_online_mask as they come up.
 436 *
 437 * This function is valid only for Open Firmware systems.  finish_device_tree
 438 * must be called before using this.
 439 *
 440 * While we're here, we may as well set the "physical" cpu ids in the paca.
 441 *
 442 * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
 443 */
 444void __init smp_setup_cpu_maps(void)
 445{
 446	struct device_node *dn;
 447	int cpu = 0;
 448	int nthreads = 1;
 449
 450	DBG("smp_setup_cpu_maps()\n");
 451
 452	cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32),
 453					__alignof__(u32));
 454	if (!cpu_to_phys_id)
 455		panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
 456		      __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32));
 457
 458	for_each_node_by_type(dn, "cpu") {
 459		const __be32 *intserv;
 460		__be32 cpu_be;
 461		int j, len;
 462
 463		DBG("  * %pOF...\n", dn);
 464
 465		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
 466				&len);
 467		if (intserv) {
 468			DBG("    ibm,ppc-interrupt-server#s -> %lu threads\n",
 469			    (len / sizeof(int)));
 470		} else {
 471			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
 472			intserv = of_get_property(dn, "reg", &len);
 473			if (!intserv) {
 474				cpu_be = cpu_to_be32(cpu);
 475				/* XXX: what is this? uninitialized?? */
 476				intserv = &cpu_be;	/* assume logical == phys */
 477				len = 4;
 478			}
 479		}
 480
 481		nthreads = len / sizeof(int);
 482
 483		for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
 484			bool avail;
 485
 486			DBG("    thread %d -> cpu %d (hard id %d)\n",
 487			    j, cpu, be32_to_cpu(intserv[j]));
 488
 489			avail = of_device_is_available(dn);
 490			if (!avail)
 491				avail = !of_property_match_string(dn,
 492						"enable-method", "spin-table");
 493
 494			set_cpu_present(cpu, avail);
 495			set_cpu_possible(cpu, true);
 496			cpu_to_phys_id[cpu] = be32_to_cpu(intserv[j]);
 497			cpu++;
 498		}
 499
 500		if (cpu >= nr_cpu_ids) {
 
 
 
 
 
 
 501			of_node_put(dn);
 502			break;
 503		}
 
 
 
 504	}
 505
 506	/* If no SMT supported, nthreads is forced to 1 */
 507	if (!cpu_has_feature(CPU_FTR_SMT)) {
 508		DBG("  SMT disabled ! nthreads forced to 1\n");
 509		nthreads = 1;
 510	}
 511
 512#ifdef CONFIG_PPC64
 513	/*
 514	 * On pSeries LPAR, we need to know how many cpus
 515	 * could possibly be added to this partition.
 516	 */
 517	if (firmware_has_feature(FW_FEATURE_LPAR) &&
 518	    (dn = of_find_node_by_path("/rtas"))) {
 519		int num_addr_cell, num_size_cell, maxcpus;
 520		const __be32 *ireg;
 521
 522		num_addr_cell = of_n_addr_cells(dn);
 523		num_size_cell = of_n_size_cells(dn);
 524
 525		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
 526
 527		if (!ireg)
 528			goto out;
 529
 530		maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
 531
 532		/* Double maxcpus for processors which have SMT capability */
 533		if (cpu_has_feature(CPU_FTR_SMT))
 534			maxcpus *= nthreads;
 535
 536		if (maxcpus > nr_cpu_ids) {
 537			printk(KERN_WARNING
 538			       "Partition configured for %d cpus, "
 539			       "operating system maximum is %u.\n",
 540			       maxcpus, nr_cpu_ids);
 541			maxcpus = nr_cpu_ids;
 542		} else
 543			printk(KERN_INFO "Partition configured for %d cpus.\n",
 544			       maxcpus);
 545
 546		for (cpu = 0; cpu < maxcpus; cpu++)
 547			set_cpu_possible(cpu, true);
 548	out:
 549		of_node_put(dn);
 550	}
 551	vdso_data->processorCount = num_present_cpus();
 552#endif /* CONFIG_PPC64 */
 553
 554        /* Initialize CPU <=> thread mapping/
 555	 *
 556	 * WARNING: We assume that the number of threads is the same for
 557	 * every CPU in the system. If that is not the case, then some code
 558	 * here will have to be reworked
 559	 */
 560	cpu_init_thread_core_maps(nthreads);
 561
 562	/* Now that possible cpus are set, set nr_cpu_ids for later use */
 563	setup_nr_cpu_ids();
 564
 565	free_unused_pacas();
 566}
 567#endif /* CONFIG_SMP */
 568
 569#ifdef CONFIG_PCSPKR_PLATFORM
 570static __init int add_pcspkr(void)
 571{
 572	struct device_node *np;
 573	struct platform_device *pd;
 574	int ret;
 575
 576	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
 577	of_node_put(np);
 578	if (!np)
 579		return -ENODEV;
 580
 581	pd = platform_device_alloc("pcspkr", -1);
 582	if (!pd)
 583		return -ENOMEM;
 584
 585	ret = platform_device_add(pd);
 586	if (ret)
 587		platform_device_put(pd);
 588
 589	return ret;
 590}
 591device_initcall(add_pcspkr);
 592#endif	/* CONFIG_PCSPKR_PLATFORM */
 593
 594static char ppc_hw_desc_buf[128] __initdata;
 595
 596struct seq_buf ppc_hw_desc __initdata = {
 597	.buffer = ppc_hw_desc_buf,
 598	.size = sizeof(ppc_hw_desc_buf),
 599	.len = 0,
 600	.readpos = 0,
 601};
 602
 603static __init void probe_machine(void)
 604{
 605	extern struct machdep_calls __machine_desc_start;
 606	extern struct machdep_calls __machine_desc_end;
 607	unsigned int i;
 608
 609	/*
 610	 * Iterate all ppc_md structures until we find the proper
 611	 * one for the current machine type
 612	 */
 613	DBG("Probing machine type ...\n");
 614
 615	/*
 616	 * Check ppc_md is empty, if not we have a bug, ie, we setup an
 617	 * entry before probe_machine() which will be overwritten
 618	 */
 619	for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
 620		if (((void **)&ppc_md)[i]) {
 621			printk(KERN_ERR "Entry %d in ppc_md non empty before"
 622			       " machine probe !\n", i);
 623		}
 624	}
 625
 626	for (machine_id = &__machine_desc_start;
 627	     machine_id < &__machine_desc_end;
 628	     machine_id++) {
 629		DBG("  %s ...", machine_id->name);
 
 
 
 
 630		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
 631		if (ppc_md.probe()) {
 632			DBG(" match !\n");
 633			break;
 634		}
 635		DBG("\n");
 636	}
 637	/* What can we do if we didn't find ? */
 638	if (machine_id >= &__machine_desc_end) {
 639		pr_err("No suitable machine description found !\n");
 640		for (;;);
 641	}
 642
 643	// Append the machine name to other info we've gathered
 644	seq_buf_puts(&ppc_hw_desc, ppc_md.name);
 645
 646	// Set the generic hardware description shown in oopses
 647	dump_stack_set_arch_desc(ppc_hw_desc.buffer);
 648
 649	pr_info("Hardware name: %s\n", ppc_hw_desc.buffer);
 650}
 651
 652/* Match a class of boards, not a specific device configuration. */
 653int check_legacy_ioport(unsigned long base_port)
 654{
 655	struct device_node *parent, *np = NULL;
 656	int ret = -ENODEV;
 657
 658	switch(base_port) {
 659	case I8042_DATA_REG:
 660		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
 661			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
 662		if (np) {
 663			parent = of_get_parent(np);
 664
 665			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
 666			if (!of_i8042_kbd_irq)
 667				of_i8042_kbd_irq = 1;
 668
 669			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
 670			if (!of_i8042_aux_irq)
 671				of_i8042_aux_irq = 12;
 672
 673			of_node_put(np);
 674			np = parent;
 675			break;
 676		}
 677		np = of_find_node_by_type(NULL, "8042");
 678		/* Pegasos has no device_type on its 8042 node, look for the
 679		 * name instead */
 680		if (!np)
 681			np = of_find_node_by_name(NULL, "8042");
 682		if (np) {
 683			of_i8042_kbd_irq = 1;
 684			of_i8042_aux_irq = 12;
 685		}
 686		break;
 687	case FDC_BASE: /* FDC1 */
 688		np = of_find_node_by_type(NULL, "fdc");
 689		break;
 690	default:
 691		/* ipmi is supposed to fail here */
 692		break;
 693	}
 694	if (!np)
 695		return ret;
 696	parent = of_get_parent(np);
 697	if (parent) {
 698		if (of_node_is_type(parent, "isa"))
 699			ret = 0;
 700		of_node_put(parent);
 701	}
 702	of_node_put(np);
 703	return ret;
 704}
 705EXPORT_SYMBOL(check_legacy_ioport);
 706
 707/*
 708 * Panic notifiers setup
 709 *
 710 * We have 3 notifiers for powerpc, each one from a different "nature":
 711 *
 712 * - ppc_panic_fadump_handler() is a hypervisor notifier, which hard-disables
 713 *   IRQs and deal with the Firmware-Assisted dump, when it is configured;
 714 *   should run early in the panic path.
 715 *
 716 * - dump_kernel_offset() is an informative notifier, just showing the KASLR
 717 *   offset if we have RANDOMIZE_BASE set.
 718 *
 719 * - ppc_panic_platform_handler() is a low-level handler that's registered
 720 *   only if the platform wishes to perform final actions in the panic path,
 721 *   hence it should run late and might not even return. Currently, only
 722 *   pseries and ps3 platforms register callbacks.
 723 */
 724static int ppc_panic_fadump_handler(struct notifier_block *this,
 725				    unsigned long event, void *ptr)
 726{
 727	/*
 728	 * panic does a local_irq_disable, but we really
 729	 * want interrupts to be hard disabled.
 730	 */
 731	hard_irq_disable();
 732
 733	/*
 734	 * If firmware-assisted dump has been registered then trigger
 735	 * its callback and let the firmware handles everything else.
 736	 */
 737	crash_fadump(NULL, ptr);
 738
 739	return NOTIFY_DONE;
 740}
 741
 742static int dump_kernel_offset(struct notifier_block *self, unsigned long v,
 743			      void *p)
 744{
 745	pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
 746		 kaslr_offset(), KERNELBASE);
 747
 748	return NOTIFY_DONE;
 749}
 750
 751static int ppc_panic_platform_handler(struct notifier_block *this,
 752				      unsigned long event, void *ptr)
 753{
 754	/*
 755	 * This handler is only registered if we have a panic callback
 756	 * on ppc_md, hence NULL check is not needed.
 757	 * Also, it may not return, so it runs really late on panic path.
 758	 */
 759	ppc_md.panic(ptr);
 760
 761	return NOTIFY_DONE;
 762}
 763
 764static struct notifier_block ppc_fadump_block = {
 765	.notifier_call = ppc_panic_fadump_handler,
 766	.priority = INT_MAX, /* run early, to notify the firmware ASAP */
 767};
 768
 769static struct notifier_block kernel_offset_notifier = {
 770	.notifier_call = dump_kernel_offset,
 771};
 772
 773static struct notifier_block ppc_panic_block = {
 774	.notifier_call = ppc_panic_platform_handler,
 775	.priority = INT_MIN, /* may not return; must be done last */
 776};
 777
 778void __init setup_panic(void)
 779{
 780	/* Hard-disables IRQs + deal with FW-assisted dump (fadump) */
 781	atomic_notifier_chain_register(&panic_notifier_list,
 782				       &ppc_fadump_block);
 783
 784	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset() > 0)
 785		atomic_notifier_chain_register(&panic_notifier_list,
 786					       &kernel_offset_notifier);
 787
 788	/* Low-level platform-specific routines that should run on panic */
 789	if (ppc_md.panic)
 790		atomic_notifier_chain_register(&panic_notifier_list,
 791					       &ppc_panic_block);
 792}
 793
 794#ifdef CONFIG_CHECK_CACHE_COHERENCY
 795/*
 796 * For platforms that have configurable cache-coherency.  This function
 797 * checks that the cache coherency setting of the kernel matches the setting
 798 * left by the firmware, as indicated in the device tree.  Since a mismatch
 799 * will eventually result in DMA failures, we print * and error and call
 800 * BUG() in that case.
 801 */
 802
 803#define KERNEL_COHERENCY	(!IS_ENABLED(CONFIG_NOT_COHERENT_CACHE))
 804
 805static int __init check_cache_coherency(void)
 806{
 807	struct device_node *np;
 808	const void *prop;
 809	bool devtree_coherency;
 810
 811	np = of_find_node_by_path("/");
 812	prop = of_get_property(np, "coherency-off", NULL);
 813	of_node_put(np);
 814
 815	devtree_coherency = prop ? false : true;
 816
 817	if (devtree_coherency != KERNEL_COHERENCY) {
 818		printk(KERN_ERR
 819			"kernel coherency:%s != device tree_coherency:%s\n",
 820			KERNEL_COHERENCY ? "on" : "off",
 821			devtree_coherency ? "on" : "off");
 822		BUG();
 823	}
 824
 825	return 0;
 826}
 827
 828late_initcall(check_cache_coherency);
 829#endif /* CONFIG_CHECK_CACHE_COHERENCY */
 830
 831void ppc_printk_progress(char *s, unsigned short hex)
 832{
 833	pr_info("%s\n", s);
 834}
 835
 836static __init void print_system_info(void)
 837{
 838	pr_info("-----------------------------------------------------\n");
 839	pr_info("phys_mem_size     = 0x%llx\n",
 840		(unsigned long long)memblock_phys_mem_size());
 841
 842	pr_info("dcache_bsize      = 0x%x\n", dcache_bsize);
 843	pr_info("icache_bsize      = 0x%x\n", icache_bsize);
 844
 845	pr_info("cpu_features      = 0x%016lx\n", cur_cpu_spec->cpu_features);
 846	pr_info("  possible        = 0x%016lx\n",
 847		(unsigned long)CPU_FTRS_POSSIBLE);
 848	pr_info("  always          = 0x%016lx\n",
 849		(unsigned long)CPU_FTRS_ALWAYS);
 850	pr_info("cpu_user_features = 0x%08x 0x%08x\n",
 851		cur_cpu_spec->cpu_user_features,
 852		cur_cpu_spec->cpu_user_features2);
 853	pr_info("mmu_features      = 0x%08x\n", cur_cpu_spec->mmu_features);
 854#ifdef CONFIG_PPC64
 855	pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
 856#ifdef CONFIG_PPC_BOOK3S
 857	pr_info("vmalloc start     = 0x%lx\n", KERN_VIRT_START);
 858	pr_info("IO start          = 0x%lx\n", KERN_IO_START);
 859	pr_info("vmemmap start     = 0x%lx\n", (unsigned long)vmemmap);
 860#endif
 861#endif
 862
 863	if (!early_radix_enabled())
 864		print_system_hash_info();
 865
 866	if (PHYSICAL_START > 0)
 867		pr_info("physical_start    = 0x%llx\n",
 868		       (unsigned long long)PHYSICAL_START);
 869	pr_info("-----------------------------------------------------\n");
 870}
 871
 872#ifdef CONFIG_SMP
 873static void __init smp_setup_pacas(void)
 874{
 875	int cpu;
 876
 877	for_each_possible_cpu(cpu) {
 878		if (cpu == smp_processor_id())
 879			continue;
 880		allocate_paca(cpu);
 881		set_hard_smp_processor_id(cpu, cpu_to_phys_id[cpu]);
 882	}
 883
 884	memblock_free(cpu_to_phys_id, nr_cpu_ids * sizeof(u32));
 885	cpu_to_phys_id = NULL;
 886}
 887#endif
 888
 889/*
 890 * Called into from start_kernel this initializes memblock, which is used
 891 * to manage page allocation until mem_init is called.
 892 */
 893void __init setup_arch(char **cmdline_p)
 894{
 895	kasan_init();
 896
 897	*cmdline_p = boot_command_line;
 898
 899	/* Set a half-reasonable default so udelay does something sensible */
 900	loops_per_jiffy = 500000000 / HZ;
 901
 902	/* Unflatten the device-tree passed by prom_init or kexec */
 903	unflatten_device_tree();
 904
 905	/*
 906	 * Initialize cache line/block info from device-tree (on ppc64) or
 907	 * just cputable (on ppc32).
 908	 */
 909	initialize_cache_info();
 910
 911	/* Initialize RTAS if available. */
 912	rtas_initialize();
 913
 914	/* Check if we have an initrd provided via the device-tree. */
 915	check_for_initrd();
 916
 917	/* Probe the machine type, establish ppc_md. */
 918	probe_machine();
 919
 920	/* Setup panic notifier if requested by the platform. */
 921	setup_panic();
 922
 923	/*
 924	 * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
 925	 * it from their respective probe() function.
 926	 */
 927	setup_power_save();
 928
 929	/* Discover standard serial ports. */
 930	find_legacy_serial_ports();
 931
 932	/* Register early console with the printk subsystem. */
 933	register_early_udbg_console();
 934
 935	/* Setup the various CPU maps based on the device-tree. */
 936	smp_setup_cpu_maps();
 937
 938	/* Initialize xmon. */
 939	xmon_setup();
 940
 941	/* Check the SMT related command line arguments (ppc64). */
 942	check_smt_enabled();
 943
 944	/* Parse memory topology */
 945	mem_topology_setup();
 
 
 946
 947	/*
 948	 * Release secondary cpus out of their spinloops at 0x60 now that
 949	 * we can map physical -> logical CPU ids.
 950	 *
 951	 * Freescale Book3e parts spin in a loop provided by firmware,
 952	 * so smp_release_cpus() does nothing for them.
 953	 */
 954#ifdef CONFIG_SMP
 955	smp_setup_pacas();
 956
 957	/* On BookE, setup per-core TLB data structures. */
 958	setup_tlb_core_data();
 959#endif
 960
 961	/* Print various info about the machine that has been gathered so far. */
 962	print_system_info();
 963
 964	klp_init_thread_info(&init_task);
 965
 966	setup_initial_init_mm(_stext, _etext, _edata, _end);
 967
 
 
 
 968	mm_iommu_init(&init_mm);
 
 969	irqstack_early_init();
 970	exc_lvl_early_init();
 971	emergency_stack_init();
 972
 973	mce_init();
 974	smp_release_cpus();
 975
 976	initmem_init();
 977
 978	/*
 979	 * Reserve large chunks of memory for use by CMA for KVM and hugetlb. These must
 980	 * be called after initmem_init(), so that pageblock_order is initialised.
 981	 */
 982	kvm_cma_reserve();
 983	gigantic_hugetlb_cma_reserve();
 984
 985	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
 986
 987	if (ppc_md.setup_arch)
 988		ppc_md.setup_arch();
 989
 990	setup_barrier_nospec();
 991	setup_spectre_v2();
 992
 993	paging_init();
 994
 995	/* Initialize the MMU context management stuff. */
 996	mmu_context_init();
 997
 998	/* Interrupt code needs to be 64K-aligned. */
 999	if (IS_ENABLED(CONFIG_PPC64) && (unsigned long)_stext & 0xffff)
1000		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
1001		      (unsigned long)_stext);
1002}
v6.9.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Common boot and setup code for both 32-bit and 64-bit.
   4 * Extracted from arch/powerpc/kernel/setup_64.c.
   5 *
   6 * Copyright (C) 2001 PPC64 Team, IBM Corp
   7 */
   8
   9#undef DEBUG
  10
  11#include <linux/export.h>
  12#include <linux/panic_notifier.h>
  13#include <linux/string.h>
  14#include <linux/sched.h>
  15#include <linux/init.h>
  16#include <linux/kernel.h>
  17#include <linux/reboot.h>
  18#include <linux/delay.h>
  19#include <linux/initrd.h>
  20#include <linux/platform_device.h>
  21#include <linux/printk.h>
  22#include <linux/seq_file.h>
  23#include <linux/ioport.h>
  24#include <linux/console.h>
 
  25#include <linux/root_dev.h>
  26#include <linux/cpu.h>
  27#include <linux/unistd.h>
  28#include <linux/seq_buf.h>
  29#include <linux/serial.h>
  30#include <linux/serial_8250.h>
  31#include <linux/percpu.h>
  32#include <linux/memblock.h>
  33#include <linux/of.h>
  34#include <linux/of_fdt.h>
  35#include <linux/of_irq.h>
  36#include <linux/hugetlb.h>
  37#include <linux/pgtable.h>
  38#include <asm/io.h>
  39#include <asm/paca.h>
  40#include <asm/processor.h>
  41#include <asm/vdso_datapage.h>
  42#include <asm/smp.h>
  43#include <asm/elf.h>
  44#include <asm/machdep.h>
  45#include <asm/time.h>
  46#include <asm/cputable.h>
  47#include <asm/sections.h>
  48#include <asm/firmware.h>
  49#include <asm/btext.h>
  50#include <asm/nvram.h>
  51#include <asm/setup.h>
  52#include <asm/rtas.h>
  53#include <asm/iommu.h>
  54#include <asm/serial.h>
  55#include <asm/cache.h>
  56#include <asm/page.h>
  57#include <asm/mmu.h>
  58#include <asm/xmon.h>
  59#include <asm/cputhreads.h>
  60#include <mm/mmu_decl.h>
  61#include <asm/archrandom.h>
  62#include <asm/fadump.h>
  63#include <asm/udbg.h>
  64#include <asm/hugetlb.h>
  65#include <asm/livepatch.h>
  66#include <asm/mmu_context.h>
  67#include <asm/cpu_has_feature.h>
  68#include <asm/kasan.h>
  69#include <asm/mce.h>
  70
  71#include "setup.h"
  72
  73#ifdef DEBUG
  74#define DBG(fmt...) udbg_printf(fmt)
  75#else
  76#define DBG(fmt...)
  77#endif
  78
  79/* The main machine-dep calls structure
  80 */
  81struct machdep_calls ppc_md;
  82EXPORT_SYMBOL(ppc_md);
  83struct machdep_calls *machine_id;
  84EXPORT_SYMBOL(machine_id);
  85
  86int boot_cpuid = -1;
  87EXPORT_SYMBOL_GPL(boot_cpuid);
  88int __initdata boot_core_hwid = -1;
  89
  90#ifdef CONFIG_PPC64
  91int boot_cpu_hwid = -1;
  92#endif
  93
  94/*
  95 * These are used in binfmt_elf.c to put aux entries on the stack
  96 * for each elf executable being started.
  97 */
  98int dcache_bsize;
  99int icache_bsize;
 100
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 101/* Variables required to store legacy IO irq routing */
 102int of_i8042_kbd_irq;
 103EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
 104int of_i8042_aux_irq;
 105EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
 106
 107#ifdef __DO_IRQ_CANON
 108/* XXX should go elsewhere eventually */
 109int ppc_do_canonicalize_irqs;
 110EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
 111#endif
 112
 113#ifdef CONFIG_CRASH_DUMP
 114/* This keeps a track of which one is the crashing cpu. */
 115int crashing_cpu = -1;
 116#endif
 117
 118/* also used by kexec */
 119void machine_shutdown(void)
 120{
 121	/*
 122	 * if fadump is active, cleanup the fadump registration before we
 123	 * shutdown.
 124	 */
 125	fadump_cleanup();
 126
 127	if (ppc_md.machine_shutdown)
 128		ppc_md.machine_shutdown();
 129}
 130
 131static void machine_hang(void)
 132{
 133	pr_emerg("System Halted, OK to turn off power\n");
 134	local_irq_disable();
 135	while (1)
 136		;
 137}
 138
 139void machine_restart(char *cmd)
 140{
 141	machine_shutdown();
 142	if (ppc_md.restart)
 143		ppc_md.restart(cmd);
 144
 145	smp_send_stop();
 146
 147	do_kernel_restart(cmd);
 148	mdelay(1000);
 149
 150	machine_hang();
 151}
 152
 153void machine_power_off(void)
 154{
 155	machine_shutdown();
 156	do_kernel_power_off();
 157	smp_send_stop();
 158	machine_hang();
 159}
 160/* Used by the G5 thermal driver */
 161EXPORT_SYMBOL_GPL(machine_power_off);
 162
 163void (*pm_power_off)(void);
 164EXPORT_SYMBOL_GPL(pm_power_off);
 165
 166size_t __must_check arch_get_random_seed_longs(unsigned long *v, size_t max_longs)
 167{
 168	if (max_longs && ppc_md.get_random_seed && ppc_md.get_random_seed(v))
 169		return 1;
 170	return 0;
 171}
 172EXPORT_SYMBOL(arch_get_random_seed_longs);
 173
 174void machine_halt(void)
 175{
 176	machine_shutdown();
 177	if (ppc_md.halt)
 178		ppc_md.halt();
 179
 180	smp_send_stop();
 181	machine_hang();
 182}
 183
 184#ifdef CONFIG_SMP
 185DEFINE_PER_CPU(unsigned int, cpu_pvr);
 186#endif
 187
 188static void show_cpuinfo_summary(struct seq_file *m)
 189{
 190	struct device_node *root;
 191	const char *model = NULL;
 192	unsigned long bogosum = 0;
 193	int i;
 194
 195	if (IS_ENABLED(CONFIG_SMP) && IS_ENABLED(CONFIG_PPC32)) {
 196		for_each_online_cpu(i)
 197			bogosum += loops_per_jiffy;
 198		seq_printf(m, "total bogomips\t: %lu.%02lu\n",
 199			   bogosum / (500000 / HZ), bogosum / (5000 / HZ) % 100);
 200	}
 201	seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
 202	if (ppc_md.name)
 203		seq_printf(m, "platform\t: %s\n", ppc_md.name);
 204	root = of_find_node_by_path("/");
 205	if (root)
 206		model = of_get_property(root, "model", NULL);
 207	if (model)
 208		seq_printf(m, "model\t\t: %s\n", model);
 209	of_node_put(root);
 210
 211	if (ppc_md.show_cpuinfo != NULL)
 212		ppc_md.show_cpuinfo(m);
 213
 214	/* Display the amount of memory */
 215	if (IS_ENABLED(CONFIG_PPC32))
 216		seq_printf(m, "Memory\t\t: %d MB\n",
 217			   (unsigned int)(total_memory / (1024 * 1024)));
 218}
 219
 220static int show_cpuinfo(struct seq_file *m, void *v)
 221{
 222	unsigned long cpu_id = (unsigned long)v - 1;
 223	unsigned int pvr;
 224	unsigned long proc_freq;
 225	unsigned short maj;
 226	unsigned short min;
 227
 228#ifdef CONFIG_SMP
 229	pvr = per_cpu(cpu_pvr, cpu_id);
 230#else
 231	pvr = mfspr(SPRN_PVR);
 232#endif
 233	maj = (pvr >> 8) & 0xFF;
 234	min = pvr & 0xFF;
 235
 236	seq_printf(m, "processor\t: %lu\ncpu\t\t: ", cpu_id);
 237
 238	if (cur_cpu_spec->pvr_mask && cur_cpu_spec->cpu_name)
 239		seq_puts(m, cur_cpu_spec->cpu_name);
 240	else
 241		seq_printf(m, "unknown (%08x)", pvr);
 242
 243	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 244		seq_puts(m, ", altivec supported");
 245
 246	seq_putc(m, '\n');
 247
 248#ifdef CONFIG_TAU
 249	if (cpu_has_feature(CPU_FTR_TAU)) {
 250		if (IS_ENABLED(CONFIG_TAU_AVERAGE)) {
 251			/* more straightforward, but potentially misleading */
 252			seq_printf(m,  "temperature \t: %u C (uncalibrated)\n",
 253				   cpu_temp(cpu_id));
 254		} else {
 255			/* show the actual temp sensor range */
 256			u32 temp;
 257			temp = cpu_temp_both(cpu_id);
 258			seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
 259				   temp & 0xff, temp >> 16);
 260		}
 261	}
 262#endif /* CONFIG_TAU */
 263
 264	/*
 265	 * Platforms that have variable clock rates, should implement
 266	 * the method ppc_md.get_proc_freq() that reports the clock
 267	 * rate of a given cpu. The rest can use ppc_proc_freq to
 268	 * report the clock rate that is same across all cpus.
 269	 */
 270	if (ppc_md.get_proc_freq)
 271		proc_freq = ppc_md.get_proc_freq(cpu_id);
 272	else
 273		proc_freq = ppc_proc_freq;
 274
 275	if (proc_freq)
 276		seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
 277			   proc_freq / 1000000, proc_freq % 1000000);
 278
 279	/* If we are a Freescale core do a simple check so
 280	 * we don't have to keep adding cases in the future */
 281	if (PVR_VER(pvr) & 0x8000) {
 282		switch (PVR_VER(pvr)) {
 283		case 0x8000:	/* 7441/7450/7451, Voyager */
 284		case 0x8001:	/* 7445/7455, Apollo 6 */
 285		case 0x8002:	/* 7447/7457, Apollo 7 */
 286		case 0x8003:	/* 7447A, Apollo 7 PM */
 287		case 0x8004:	/* 7448, Apollo 8 */
 288		case 0x800c:	/* 7410, Nitro */
 289			maj = ((pvr >> 8) & 0xF);
 290			min = PVR_MIN(pvr);
 291			break;
 292		default:	/* e500/book-e */
 293			maj = PVR_MAJ(pvr);
 294			min = PVR_MIN(pvr);
 295			break;
 296		}
 297	} else {
 298		switch (PVR_VER(pvr)) {
 299			case 0x1008:	/* 740P/750P ?? */
 300				maj = ((pvr >> 8) & 0xFF) - 1;
 301				min = pvr & 0xFF;
 302				break;
 303			case 0x004e: /* POWER9 bits 12-15 give chip type */
 304			case 0x0080: /* POWER10 bit 12 gives SMT8/4 */
 305				maj = (pvr >> 8) & 0x0F;
 306				min = pvr & 0xFF;
 307				break;
 308			default:
 309				maj = (pvr >> 8) & 0xFF;
 310				min = pvr & 0xFF;
 311				break;
 312		}
 313	}
 314
 315	seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
 316		   maj, min, PVR_VER(pvr), PVR_REV(pvr));
 317
 318	if (IS_ENABLED(CONFIG_PPC32))
 319		seq_printf(m, "bogomips\t: %lu.%02lu\n", loops_per_jiffy / (500000 / HZ),
 320			   (loops_per_jiffy / (5000 / HZ)) % 100);
 321
 322	seq_putc(m, '\n');
 323
 324	/* If this is the last cpu, print the summary */
 325	if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
 326		show_cpuinfo_summary(m);
 327
 328	return 0;
 329}
 330
 331static void *c_start(struct seq_file *m, loff_t *pos)
 332{
 333	if (*pos == 0)	/* just in case, cpu 0 is not the first */
 334		*pos = cpumask_first(cpu_online_mask);
 335	else
 336		*pos = cpumask_next(*pos - 1, cpu_online_mask);
 337	if ((*pos) < nr_cpu_ids)
 338		return (void *)(unsigned long)(*pos + 1);
 339	return NULL;
 340}
 341
 342static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 343{
 344	(*pos)++;
 345	return c_start(m, pos);
 346}
 347
 348static void c_stop(struct seq_file *m, void *v)
 349{
 350}
 351
 352const struct seq_operations cpuinfo_op = {
 353	.start	= c_start,
 354	.next	= c_next,
 355	.stop	= c_stop,
 356	.show	= show_cpuinfo,
 357};
 358
 359void __init check_for_initrd(void)
 360{
 361#ifdef CONFIG_BLK_DEV_INITRD
 362	DBG(" -> check_for_initrd()  initrd_start=0x%lx  initrd_end=0x%lx\n",
 363	    initrd_start, initrd_end);
 364
 365	/* If we were passed an initrd, set the ROOT_DEV properly if the values
 366	 * look sensible. If not, clear initrd reference.
 367	 */
 368	if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
 369	    initrd_end > initrd_start)
 370		ROOT_DEV = Root_RAM0;
 371	else
 372		initrd_start = initrd_end = 0;
 373
 374	if (initrd_start)
 375		pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
 376
 377	DBG(" <- check_for_initrd()\n");
 378#endif /* CONFIG_BLK_DEV_INITRD */
 379}
 380
 381#ifdef CONFIG_SMP
 382
 383int threads_per_core, threads_per_subcore, threads_shift __read_mostly;
 384cpumask_t threads_core_mask __read_mostly;
 385EXPORT_SYMBOL_GPL(threads_per_core);
 386EXPORT_SYMBOL_GPL(threads_per_subcore);
 387EXPORT_SYMBOL_GPL(threads_shift);
 388EXPORT_SYMBOL_GPL(threads_core_mask);
 389
 390static void __init cpu_init_thread_core_maps(int tpc)
 391{
 392	int i;
 393
 394	threads_per_core = tpc;
 395	threads_per_subcore = tpc;
 396	cpumask_clear(&threads_core_mask);
 397
 398	/* This implementation only supports power of 2 number of threads
 399	 * for simplicity and performance
 400	 */
 401	threads_shift = ilog2(tpc);
 402	BUG_ON(tpc != (1 << threads_shift));
 403
 404	for (i = 0; i < tpc; i++)
 405		cpumask_set_cpu(i, &threads_core_mask);
 406
 407	printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
 408	       tpc, tpc > 1 ? "s" : "");
 409	printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
 410}
 411
 412
 413u32 *cpu_to_phys_id = NULL;
 414
 415static int assign_threads(unsigned int cpu, unsigned int nthreads, bool present,
 416			  const __be32 *hw_ids)
 417{
 418	for (int i = 0; i < nthreads && cpu < nr_cpu_ids; i++) {
 419		__be32 hwid;
 420
 421		hwid = be32_to_cpu(hw_ids[i]);
 422
 423		DBG("    thread %d -> cpu %d (hard id %d)\n", i, cpu, hwid);
 424
 425		set_cpu_present(cpu, present);
 426		set_cpu_possible(cpu, true);
 427		cpu_to_phys_id[cpu] = hwid;
 428		cpu++;
 429	}
 430
 431	return cpu;
 432}
 433
 434/**
 435 * setup_cpu_maps - initialize the following cpu maps:
 436 *                  cpu_possible_mask
 437 *                  cpu_present_mask
 438 *
 439 * Having the possible map set up early allows us to restrict allocations
 440 * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
 441 *
 442 * We do not initialize the online map here; cpus set their own bits in
 443 * cpu_online_mask as they come up.
 444 *
 445 * This function is valid only for Open Firmware systems.  finish_device_tree
 446 * must be called before using this.
 447 *
 448 * While we're here, we may as well set the "physical" cpu ids in the paca.
 449 *
 450 * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
 451 */
 452void __init smp_setup_cpu_maps(void)
 453{
 454	struct device_node *dn;
 455	int cpu = 0;
 456	int nthreads = 1;
 457
 458	DBG("smp_setup_cpu_maps()\n");
 459
 460	cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32),
 461					__alignof__(u32));
 462	if (!cpu_to_phys_id)
 463		panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
 464		      __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32));
 465
 466	for_each_node_by_type(dn, "cpu") {
 467		const __be32 *intserv;
 468		__be32 cpu_be;
 469		int len;
 470
 471		DBG("  * %pOF...\n", dn);
 472
 473		intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
 474				&len);
 475		if (intserv) {
 476			DBG("    ibm,ppc-interrupt-server#s -> %lu threads\n",
 477			    (len / sizeof(int)));
 478		} else {
 479			DBG("    no ibm,ppc-interrupt-server#s -> 1 thread\n");
 480			intserv = of_get_property(dn, "reg", &len);
 481			if (!intserv) {
 482				cpu_be = cpu_to_be32(cpu);
 483				/* XXX: what is this? uninitialized?? */
 484				intserv = &cpu_be;	/* assume logical == phys */
 485				len = 4;
 486			}
 487		}
 488
 489		nthreads = len / sizeof(int);
 490
 491		bool avail = of_device_is_available(dn);
 492		if (!avail)
 493			avail = !of_property_match_string(dn,
 494					"enable-method", "spin-table");
 495
 496		if (boot_core_hwid >= 0) {
 497			if (cpu == 0) {
 498				pr_info("Skipping CPU node %pOF to allow for boot core.\n", dn);
 499				cpu = nthreads;
 500				continue;
 501			}
 
 
 
 
 
 502
 503			if (be32_to_cpu(intserv[0]) == boot_core_hwid) {
 504				pr_info("Renumbered boot core %pOF to logical 0\n", dn);
 505				assign_threads(0, nthreads, avail, intserv);
 506				of_node_put(dn);
 507				break;
 508			}
 509		} else if (cpu >= nr_cpu_ids) {
 510			of_node_put(dn);
 511			break;
 512		}
 513
 514		if (cpu < nr_cpu_ids)
 515			cpu = assign_threads(cpu, nthreads, avail, intserv);
 516	}
 517
 518	/* If no SMT supported, nthreads is forced to 1 */
 519	if (!cpu_has_feature(CPU_FTR_SMT)) {
 520		DBG("  SMT disabled ! nthreads forced to 1\n");
 521		nthreads = 1;
 522	}
 523
 524#ifdef CONFIG_PPC64
 525	/*
 526	 * On pSeries LPAR, we need to know how many cpus
 527	 * could possibly be added to this partition.
 528	 */
 529	if (firmware_has_feature(FW_FEATURE_LPAR) &&
 530	    (dn = of_find_node_by_path("/rtas"))) {
 531		int num_addr_cell, num_size_cell, maxcpus;
 532		const __be32 *ireg;
 533
 534		num_addr_cell = of_n_addr_cells(dn);
 535		num_size_cell = of_n_size_cells(dn);
 536
 537		ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
 538
 539		if (!ireg)
 540			goto out;
 541
 542		maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
 543
 544		/* Double maxcpus for processors which have SMT capability */
 545		if (cpu_has_feature(CPU_FTR_SMT))
 546			maxcpus *= nthreads;
 547
 548		if (maxcpus > nr_cpu_ids) {
 549			printk(KERN_WARNING
 550			       "Partition configured for %d cpus, "
 551			       "operating system maximum is %u.\n",
 552			       maxcpus, nr_cpu_ids);
 553			maxcpus = nr_cpu_ids;
 554		} else
 555			printk(KERN_INFO "Partition configured for %d cpus.\n",
 556			       maxcpus);
 557
 558		for (cpu = 0; cpu < maxcpus; cpu++)
 559			set_cpu_possible(cpu, true);
 560	out:
 561		of_node_put(dn);
 562	}
 563	vdso_data->processorCount = num_present_cpus();
 564#endif /* CONFIG_PPC64 */
 565
 566        /* Initialize CPU <=> thread mapping/
 567	 *
 568	 * WARNING: We assume that the number of threads is the same for
 569	 * every CPU in the system. If that is not the case, then some code
 570	 * here will have to be reworked
 571	 */
 572	cpu_init_thread_core_maps(nthreads);
 573
 574	/* Now that possible cpus are set, set nr_cpu_ids for later use */
 575	setup_nr_cpu_ids();
 576
 577	free_unused_pacas();
 578}
 579#endif /* CONFIG_SMP */
 580
 581#ifdef CONFIG_PCSPKR_PLATFORM
 582static __init int add_pcspkr(void)
 583{
 584	struct device_node *np;
 585	struct platform_device *pd;
 586	int ret;
 587
 588	np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
 589	of_node_put(np);
 590	if (!np)
 591		return -ENODEV;
 592
 593	pd = platform_device_alloc("pcspkr", -1);
 594	if (!pd)
 595		return -ENOMEM;
 596
 597	ret = platform_device_add(pd);
 598	if (ret)
 599		platform_device_put(pd);
 600
 601	return ret;
 602}
 603device_initcall(add_pcspkr);
 604#endif	/* CONFIG_PCSPKR_PLATFORM */
 605
 606static char ppc_hw_desc_buf[128] __initdata;
 607
 608struct seq_buf ppc_hw_desc __initdata = {
 609	.buffer = ppc_hw_desc_buf,
 610	.size = sizeof(ppc_hw_desc_buf),
 611	.len = 0,
 
 612};
 613
 614static __init void probe_machine(void)
 615{
 616	extern struct machdep_calls __machine_desc_start;
 617	extern struct machdep_calls __machine_desc_end;
 618	unsigned int i;
 619
 620	/*
 621	 * Iterate all ppc_md structures until we find the proper
 622	 * one for the current machine type
 623	 */
 624	DBG("Probing machine type ...\n");
 625
 626	/*
 627	 * Check ppc_md is empty, if not we have a bug, ie, we setup an
 628	 * entry before probe_machine() which will be overwritten
 629	 */
 630	for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
 631		if (((void **)&ppc_md)[i]) {
 632			printk(KERN_ERR "Entry %d in ppc_md non empty before"
 633			       " machine probe !\n", i);
 634		}
 635	}
 636
 637	for (machine_id = &__machine_desc_start;
 638	     machine_id < &__machine_desc_end;
 639	     machine_id++) {
 640		DBG("  %s ...\n", machine_id->name);
 641		if (machine_id->compatible && !of_machine_is_compatible(machine_id->compatible))
 642			continue;
 643		if (machine_id->compatibles && !of_machine_compatible_match(machine_id->compatibles))
 644			continue;
 645		memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
 646		if (ppc_md.probe && !ppc_md.probe())
 647			continue;
 648		DBG("   %s match !\n", machine_id->name);
 649		break;
 
 650	}
 651	/* What can we do if we didn't find ? */
 652	if (machine_id >= &__machine_desc_end) {
 653		pr_err("No suitable machine description found !\n");
 654		for (;;);
 655	}
 656
 657	// Append the machine name to other info we've gathered
 658	seq_buf_puts(&ppc_hw_desc, ppc_md.name);
 659
 660	// Set the generic hardware description shown in oopses
 661	dump_stack_set_arch_desc(ppc_hw_desc.buffer);
 662
 663	pr_info("Hardware name: %s\n", ppc_hw_desc.buffer);
 664}
 665
 666/* Match a class of boards, not a specific device configuration. */
 667int check_legacy_ioport(unsigned long base_port)
 668{
 669	struct device_node *parent, *np = NULL;
 670	int ret = -ENODEV;
 671
 672	switch(base_port) {
 673	case I8042_DATA_REG:
 674		if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
 675			np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
 676		if (np) {
 677			parent = of_get_parent(np);
 678
 679			of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
 680			if (!of_i8042_kbd_irq)
 681				of_i8042_kbd_irq = 1;
 682
 683			of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
 684			if (!of_i8042_aux_irq)
 685				of_i8042_aux_irq = 12;
 686
 687			of_node_put(np);
 688			np = parent;
 689			break;
 690		}
 691		np = of_find_node_by_type(NULL, "8042");
 692		/* Pegasos has no device_type on its 8042 node, look for the
 693		 * name instead */
 694		if (!np)
 695			np = of_find_node_by_name(NULL, "8042");
 696		if (np) {
 697			of_i8042_kbd_irq = 1;
 698			of_i8042_aux_irq = 12;
 699		}
 700		break;
 701	case FDC_BASE: /* FDC1 */
 702		np = of_find_node_by_type(NULL, "fdc");
 703		break;
 704	default:
 705		/* ipmi is supposed to fail here */
 706		break;
 707	}
 708	if (!np)
 709		return ret;
 710	parent = of_get_parent(np);
 711	if (parent) {
 712		if (of_node_is_type(parent, "isa"))
 713			ret = 0;
 714		of_node_put(parent);
 715	}
 716	of_node_put(np);
 717	return ret;
 718}
 719EXPORT_SYMBOL(check_legacy_ioport);
 720
 721/*
 722 * Panic notifiers setup
 723 *
 724 * We have 3 notifiers for powerpc, each one from a different "nature":
 725 *
 726 * - ppc_panic_fadump_handler() is a hypervisor notifier, which hard-disables
 727 *   IRQs and deal with the Firmware-Assisted dump, when it is configured;
 728 *   should run early in the panic path.
 729 *
 730 * - dump_kernel_offset() is an informative notifier, just showing the KASLR
 731 *   offset if we have RANDOMIZE_BASE set.
 732 *
 733 * - ppc_panic_platform_handler() is a low-level handler that's registered
 734 *   only if the platform wishes to perform final actions in the panic path,
 735 *   hence it should run late and might not even return. Currently, only
 736 *   pseries and ps3 platforms register callbacks.
 737 */
 738static int ppc_panic_fadump_handler(struct notifier_block *this,
 739				    unsigned long event, void *ptr)
 740{
 741	/*
 742	 * panic does a local_irq_disable, but we really
 743	 * want interrupts to be hard disabled.
 744	 */
 745	hard_irq_disable();
 746
 747	/*
 748	 * If firmware-assisted dump has been registered then trigger
 749	 * its callback and let the firmware handles everything else.
 750	 */
 751	crash_fadump(NULL, ptr);
 752
 753	return NOTIFY_DONE;
 754}
 755
 756static int dump_kernel_offset(struct notifier_block *self, unsigned long v,
 757			      void *p)
 758{
 759	pr_emerg("Kernel Offset: 0x%lx from 0x%lx\n",
 760		 kaslr_offset(), KERNELBASE);
 761
 762	return NOTIFY_DONE;
 763}
 764
 765static int ppc_panic_platform_handler(struct notifier_block *this,
 766				      unsigned long event, void *ptr)
 767{
 768	/*
 769	 * This handler is only registered if we have a panic callback
 770	 * on ppc_md, hence NULL check is not needed.
 771	 * Also, it may not return, so it runs really late on panic path.
 772	 */
 773	ppc_md.panic(ptr);
 774
 775	return NOTIFY_DONE;
 776}
 777
 778static struct notifier_block ppc_fadump_block = {
 779	.notifier_call = ppc_panic_fadump_handler,
 780	.priority = INT_MAX, /* run early, to notify the firmware ASAP */
 781};
 782
 783static struct notifier_block kernel_offset_notifier = {
 784	.notifier_call = dump_kernel_offset,
 785};
 786
 787static struct notifier_block ppc_panic_block = {
 788	.notifier_call = ppc_panic_platform_handler,
 789	.priority = INT_MIN, /* may not return; must be done last */
 790};
 791
 792void __init setup_panic(void)
 793{
 794	/* Hard-disables IRQs + deal with FW-assisted dump (fadump) */
 795	atomic_notifier_chain_register(&panic_notifier_list,
 796				       &ppc_fadump_block);
 797
 798	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_offset() > 0)
 799		atomic_notifier_chain_register(&panic_notifier_list,
 800					       &kernel_offset_notifier);
 801
 802	/* Low-level platform-specific routines that should run on panic */
 803	if (ppc_md.panic)
 804		atomic_notifier_chain_register(&panic_notifier_list,
 805					       &ppc_panic_block);
 806}
 807
 808#ifdef CONFIG_CHECK_CACHE_COHERENCY
 809/*
 810 * For platforms that have configurable cache-coherency.  This function
 811 * checks that the cache coherency setting of the kernel matches the setting
 812 * left by the firmware, as indicated in the device tree.  Since a mismatch
 813 * will eventually result in DMA failures, we print * and error and call
 814 * BUG() in that case.
 815 */
 816
 817#define KERNEL_COHERENCY	(!IS_ENABLED(CONFIG_NOT_COHERENT_CACHE))
 818
 819static int __init check_cache_coherency(void)
 820{
 821	struct device_node *np;
 822	const void *prop;
 823	bool devtree_coherency;
 824
 825	np = of_find_node_by_path("/");
 826	prop = of_get_property(np, "coherency-off", NULL);
 827	of_node_put(np);
 828
 829	devtree_coherency = prop ? false : true;
 830
 831	if (devtree_coherency != KERNEL_COHERENCY) {
 832		printk(KERN_ERR
 833			"kernel coherency:%s != device tree_coherency:%s\n",
 834			KERNEL_COHERENCY ? "on" : "off",
 835			devtree_coherency ? "on" : "off");
 836		BUG();
 837	}
 838
 839	return 0;
 840}
 841
 842late_initcall(check_cache_coherency);
 843#endif /* CONFIG_CHECK_CACHE_COHERENCY */
 844
 845void ppc_printk_progress(char *s, unsigned short hex)
 846{
 847	pr_info("%s\n", s);
 848}
 849
 850static __init void print_system_info(void)
 851{
 852	pr_info("-----------------------------------------------------\n");
 853	pr_info("phys_mem_size     = 0x%llx\n",
 854		(unsigned long long)memblock_phys_mem_size());
 855
 856	pr_info("dcache_bsize      = 0x%x\n", dcache_bsize);
 857	pr_info("icache_bsize      = 0x%x\n", icache_bsize);
 858
 859	pr_info("cpu_features      = 0x%016lx\n", cur_cpu_spec->cpu_features);
 860	pr_info("  possible        = 0x%016lx\n",
 861		(unsigned long)CPU_FTRS_POSSIBLE);
 862	pr_info("  always          = 0x%016lx\n",
 863		(unsigned long)CPU_FTRS_ALWAYS);
 864	pr_info("cpu_user_features = 0x%08x 0x%08x\n",
 865		cur_cpu_spec->cpu_user_features,
 866		cur_cpu_spec->cpu_user_features2);
 867	pr_info("mmu_features      = 0x%08x\n", cur_cpu_spec->mmu_features);
 868#ifdef CONFIG_PPC64
 869	pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
 870#ifdef CONFIG_PPC_BOOK3S
 871	pr_info("vmalloc start     = 0x%lx\n", KERN_VIRT_START);
 872	pr_info("IO start          = 0x%lx\n", KERN_IO_START);
 873	pr_info("vmemmap start     = 0x%lx\n", (unsigned long)vmemmap);
 874#endif
 875#endif
 876
 877	if (!early_radix_enabled())
 878		print_system_hash_info();
 879
 880	if (PHYSICAL_START > 0)
 881		pr_info("physical_start    = 0x%llx\n",
 882		       (unsigned long long)PHYSICAL_START);
 883	pr_info("-----------------------------------------------------\n");
 884}
 885
 886#ifdef CONFIG_SMP
 887static void __init smp_setup_pacas(void)
 888{
 889	int cpu;
 890
 891	for_each_possible_cpu(cpu) {
 892		if (cpu == smp_processor_id())
 893			continue;
 894		allocate_paca(cpu);
 895		set_hard_smp_processor_id(cpu, cpu_to_phys_id[cpu]);
 896	}
 897
 898	memblock_free(cpu_to_phys_id, nr_cpu_ids * sizeof(u32));
 899	cpu_to_phys_id = NULL;
 900}
 901#endif
 902
 903/*
 904 * Called into from start_kernel this initializes memblock, which is used
 905 * to manage page allocation until mem_init is called.
 906 */
 907void __init setup_arch(char **cmdline_p)
 908{
 909	kasan_init();
 910
 911	*cmdline_p = boot_command_line;
 912
 913	/* Set a half-reasonable default so udelay does something sensible */
 914	loops_per_jiffy = 500000000 / HZ;
 915
 916	/* Unflatten the device-tree passed by prom_init or kexec */
 917	unflatten_device_tree();
 918
 919	/*
 920	 * Initialize cache line/block info from device-tree (on ppc64) or
 921	 * just cputable (on ppc32).
 922	 */
 923	initialize_cache_info();
 924
 925	/* Initialize RTAS if available. */
 926	rtas_initialize();
 927
 928	/* Check if we have an initrd provided via the device-tree. */
 929	check_for_initrd();
 930
 931	/* Probe the machine type, establish ppc_md. */
 932	probe_machine();
 933
 934	/* Setup panic notifier if requested by the platform. */
 935	setup_panic();
 936
 937	/*
 938	 * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
 939	 * it from their respective probe() function.
 940	 */
 941	setup_power_save();
 942
 943	/* Discover standard serial ports. */
 944	find_legacy_serial_ports();
 945
 946	/* Register early console with the printk subsystem. */
 947	register_early_udbg_console();
 948
 949	/* Setup the various CPU maps based on the device-tree. */
 950	smp_setup_cpu_maps();
 951
 952	/* Initialize xmon. */
 953	xmon_setup();
 954
 955	/* Check the SMT related command line arguments (ppc64). */
 956	check_smt_enabled();
 957
 958	/* Parse memory topology */
 959	mem_topology_setup();
 960	/* Set max_mapnr before paging_init() */
 961	set_max_mapnr(max_pfn);
 962
 963	/*
 964	 * Release secondary cpus out of their spinloops at 0x60 now that
 965	 * we can map physical -> logical CPU ids.
 966	 *
 967	 * Freescale Book3e parts spin in a loop provided by firmware,
 968	 * so smp_release_cpus() does nothing for them.
 969	 */
 970#ifdef CONFIG_SMP
 971	smp_setup_pacas();
 972
 973	/* On BookE, setup per-core TLB data structures. */
 974	setup_tlb_core_data();
 975#endif
 976
 977	/* Print various info about the machine that has been gathered so far. */
 978	print_system_info();
 979
 980	klp_init_thread_info(&init_task);
 981
 982	setup_initial_init_mm(_stext, _etext, _edata, _end);
 983	/* sched_init() does the mmgrab(&init_mm) for the primary CPU */
 984	VM_WARN_ON(cpumask_test_cpu(smp_processor_id(), mm_cpumask(&init_mm)));
 985	cpumask_set_cpu(smp_processor_id(), mm_cpumask(&init_mm));
 986	inc_mm_active_cpus(&init_mm);
 987	mm_iommu_init(&init_mm);
 988
 989	irqstack_early_init();
 990	exc_lvl_early_init();
 991	emergency_stack_init();
 992
 993	mce_init();
 994	smp_release_cpus();
 995
 996	initmem_init();
 997
 998	/*
 999	 * Reserve large chunks of memory for use by CMA for KVM and hugetlb. These must
1000	 * be called after initmem_init(), so that pageblock_order is initialised.
1001	 */
1002	kvm_cma_reserve();
1003	gigantic_hugetlb_cma_reserve();
1004
1005	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
1006
1007	if (ppc_md.setup_arch)
1008		ppc_md.setup_arch();
1009
1010	setup_barrier_nospec();
1011	setup_spectre_v2();
1012
1013	paging_init();
1014
1015	/* Initialize the MMU context management stuff. */
1016	mmu_context_init();
1017
1018	/* Interrupt code needs to be 64K-aligned. */
1019	if (IS_ENABLED(CONFIG_PPC64) && (unsigned long)_stext & 0xffff)
1020		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
1021		      (unsigned long)_stext);
1022}