2 * Common boot and setup code for both 32-bit and 64-bit.
3 * Extracted from arch/powerpc/kernel/setup_64.c.
5 * Copyright (C) 2001 PPC64 Team, IBM Corp
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
15 #include <linux/export.h>
16 #include <linux/string.h>
17 #include <linux/sched.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/reboot.h>
21 #include <linux/delay.h>
22 #include <linux/initrd.h>
23 #include <linux/platform_device.h>
24 #include <linux/seq_file.h>
25 #include <linux/ioport.h>
26 #include <linux/console.h>
27 #include <linux/screen_info.h>
28 #include <linux/root_dev.h>
29 #include <linux/notifier.h>
30 #include <linux/cpu.h>
31 #include <linux/unistd.h>
32 #include <linux/serial.h>
33 #include <linux/serial_8250.h>
34 #include <linux/debugfs.h>
35 #include <linux/percpu.h>
36 #include <linux/memblock.h>
37 #include <linux/of_platform.h>
38 #include <linux/hugetlb.h>
42 #include <asm/processor.h>
43 #include <asm/vdso_datapage.h>
44 #include <asm/pgtable.h>
47 #include <asm/machdep.h>
49 #include <asm/cputable.h>
50 #include <asm/sections.h>
51 #include <asm/firmware.h>
52 #include <asm/btext.h>
53 #include <asm/nvram.h>
54 #include <asm/setup.h>
56 #include <asm/iommu.h>
57 #include <asm/serial.h>
58 #include <asm/cache.h>
62 #include <asm/cputhreads.h>
63 #include <mm/mmu_decl.h>
64 #include <asm/fadump.h>
66 #include <asm/hugetlb.h>
67 #include <asm/livepatch.h>
68 #include <asm/mmu_context.h>
69 #include <asm/cpu_has_feature.h>
75 #define DBG(fmt...) udbg_printf(fmt)
80 /* The main machine-dep calls structure
82 struct machdep_calls ppc_md;
83 EXPORT_SYMBOL(ppc_md);
84 struct machdep_calls *machine_id;
85 EXPORT_SYMBOL(machine_id);
88 EXPORT_SYMBOL_GPL(boot_cpuid);
91 * These are used in binfmt_elf.c to put aux entries on the stack
92 * for each elf executable being started.
99 unsigned long klimit = (unsigned long) _end;
102 * This still seems to be needed... -- paulus
104 struct screen_info screen_info = {
107 .orig_video_cols = 80,
108 .orig_video_lines = 25,
109 .orig_video_isVGA = 1,
110 .orig_video_points = 16
112 #if defined(CONFIG_FB_VGA16_MODULE)
113 EXPORT_SYMBOL(screen_info);
116 /* Variables required to store legacy IO irq routing */
117 int of_i8042_kbd_irq;
118 EXPORT_SYMBOL_GPL(of_i8042_kbd_irq);
119 int of_i8042_aux_irq;
120 EXPORT_SYMBOL_GPL(of_i8042_aux_irq);
122 #ifdef __DO_IRQ_CANON
123 /* XXX should go elsewhere eventually */
124 int ppc_do_canonicalize_irqs;
125 EXPORT_SYMBOL(ppc_do_canonicalize_irqs);
128 /* also used by kexec */
129 void machine_shutdown(void)
131 #ifdef CONFIG_FA_DUMP
133 * if fadump is active, cleanup the fadump registration before we
139 if (ppc_md.machine_shutdown)
140 ppc_md.machine_shutdown();
143 static void machine_hang(void)
145 pr_emerg("System Halted, OK to turn off power\n");
151 void machine_restart(char *cmd)
159 do_kernel_restart(cmd);
165 void machine_power_off(void)
174 /* Used by the G5 thermal driver */
175 EXPORT_SYMBOL_GPL(machine_power_off);
177 void (*pm_power_off)(void);
178 EXPORT_SYMBOL_GPL(pm_power_off);
180 void machine_halt(void)
192 extern u32 cpu_temp(unsigned long cpu);
193 extern u32 cpu_temp_both(unsigned long cpu);
194 #endif /* CONFIG_TAU */
197 DEFINE_PER_CPU(unsigned int, cpu_pvr);
200 static void show_cpuinfo_summary(struct seq_file *m)
202 struct device_node *root;
203 const char *model = NULL;
204 #if defined(CONFIG_SMP) && defined(CONFIG_PPC32)
205 unsigned long bogosum = 0;
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 #endif /* CONFIG_SMP && CONFIG_PPC32 */
212 seq_printf(m, "timebase\t: %lu\n", ppc_tb_freq);
214 seq_printf(m, "platform\t: %s\n", ppc_md.name);
215 root = of_find_node_by_path("/");
217 model = of_get_property(root, "model", NULL);
219 seq_printf(m, "model\t\t: %s\n", model);
222 if (ppc_md.show_cpuinfo != NULL)
223 ppc_md.show_cpuinfo(m);
226 /* Display the amount of memory */
227 seq_printf(m, "Memory\t\t: %d MB\n",
228 (unsigned int)(total_memory / (1024 * 1024)));
232 static int show_cpuinfo(struct seq_file *m, void *v)
234 unsigned long cpu_id = (unsigned long)v - 1;
236 unsigned long proc_freq;
240 /* We only show online cpus: disable preempt (overzealous, I
241 * knew) to prevent cpu going down. */
243 if (!cpu_online(cpu_id)) {
249 pvr = per_cpu(cpu_pvr, cpu_id);
251 pvr = mfspr(SPRN_PVR);
253 maj = (pvr >> 8) & 0xFF;
256 seq_printf(m, "processor\t: %lu\n", cpu_id);
257 seq_printf(m, "cpu\t\t: ");
259 if (cur_cpu_spec->pvr_mask)
260 seq_printf(m, "%s", cur_cpu_spec->cpu_name);
262 seq_printf(m, "unknown (%08x)", pvr);
264 #ifdef CONFIG_ALTIVEC
265 if (cpu_has_feature(CPU_FTR_ALTIVEC))
266 seq_printf(m, ", altivec supported");
267 #endif /* CONFIG_ALTIVEC */
272 if (cur_cpu_spec->cpu_features & CPU_FTR_TAU) {
273 #ifdef CONFIG_TAU_AVERAGE
274 /* more straightforward, but potentially misleading */
275 seq_printf(m, "temperature \t: %u C (uncalibrated)\n",
278 /* show the actual temp sensor range */
280 temp = cpu_temp_both(cpu_id);
281 seq_printf(m, "temperature \t: %u-%u C (uncalibrated)\n",
282 temp & 0xff, temp >> 16);
285 #endif /* CONFIG_TAU */
288 * Platforms that have variable clock rates, should implement
289 * the method ppc_md.get_proc_freq() that reports the clock
290 * rate of a given cpu. The rest can use ppc_proc_freq to
291 * report the clock rate that is same across all cpus.
293 if (ppc_md.get_proc_freq)
294 proc_freq = ppc_md.get_proc_freq(cpu_id);
296 proc_freq = ppc_proc_freq;
299 seq_printf(m, "clock\t\t: %lu.%06luMHz\n",
300 proc_freq / 1000000, proc_freq % 1000000);
302 if (ppc_md.show_percpuinfo != NULL)
303 ppc_md.show_percpuinfo(m, cpu_id);
305 /* If we are a Freescale core do a simple check so
306 * we dont have to keep adding cases in the future */
307 if (PVR_VER(pvr) & 0x8000) {
308 switch (PVR_VER(pvr)) {
309 case 0x8000: /* 7441/7450/7451, Voyager */
310 case 0x8001: /* 7445/7455, Apollo 6 */
311 case 0x8002: /* 7447/7457, Apollo 7 */
312 case 0x8003: /* 7447A, Apollo 7 PM */
313 case 0x8004: /* 7448, Apollo 8 */
314 case 0x800c: /* 7410, Nitro */
315 maj = ((pvr >> 8) & 0xF);
318 default: /* e500/book-e */
324 switch (PVR_VER(pvr)) {
325 case 0x0020: /* 403 family */
326 maj = PVR_MAJ(pvr) + 1;
329 case 0x1008: /* 740P/750P ?? */
330 maj = ((pvr >> 8) & 0xFF) - 1;
334 maj = (pvr >> 8) & 0xFF;
340 seq_printf(m, "revision\t: %hd.%hd (pvr %04x %04x)\n",
341 maj, min, PVR_VER(pvr), PVR_REV(pvr));
344 seq_printf(m, "bogomips\t: %lu.%02lu\n",
345 loops_per_jiffy / (500000/HZ),
346 (loops_per_jiffy / (5000/HZ)) % 100);
355 /* If this is the last cpu, print the summary */
356 if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids)
357 show_cpuinfo_summary(m);
362 static void *c_start(struct seq_file *m, loff_t *pos)
364 if (*pos == 0) /* just in case, cpu 0 is not the first */
365 *pos = cpumask_first(cpu_online_mask);
367 *pos = cpumask_next(*pos - 1, cpu_online_mask);
368 if ((*pos) < nr_cpu_ids)
369 return (void *)(unsigned long)(*pos + 1);
373 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
376 return c_start(m, pos);
379 static void c_stop(struct seq_file *m, void *v)
383 const struct seq_operations cpuinfo_op = {
387 .show = show_cpuinfo,
390 void __init check_for_initrd(void)
392 #ifdef CONFIG_BLK_DEV_INITRD
393 DBG(" -> check_for_initrd() initrd_start=0x%lx initrd_end=0x%lx\n",
394 initrd_start, initrd_end);
396 /* If we were passed an initrd, set the ROOT_DEV properly if the values
397 * look sensible. If not, clear initrd reference.
399 if (is_kernel_addr(initrd_start) && is_kernel_addr(initrd_end) &&
400 initrd_end > initrd_start)
401 ROOT_DEV = Root_RAM0;
403 initrd_start = initrd_end = 0;
406 pr_info("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
408 DBG(" <- check_for_initrd()\n");
409 #endif /* CONFIG_BLK_DEV_INITRD */
414 int threads_per_core, threads_per_subcore, threads_shift;
415 cpumask_t threads_core_mask;
416 EXPORT_SYMBOL_GPL(threads_per_core);
417 EXPORT_SYMBOL_GPL(threads_per_subcore);
418 EXPORT_SYMBOL_GPL(threads_shift);
419 EXPORT_SYMBOL_GPL(threads_core_mask);
421 static void __init cpu_init_thread_core_maps(int tpc)
425 threads_per_core = tpc;
426 threads_per_subcore = tpc;
427 cpumask_clear(&threads_core_mask);
429 /* This implementation only supports power of 2 number of threads
430 * for simplicity and performance
432 threads_shift = ilog2(tpc);
433 BUG_ON(tpc != (1 << threads_shift));
435 for (i = 0; i < tpc; i++)
436 cpumask_set_cpu(i, &threads_core_mask);
438 printk(KERN_INFO "CPU maps initialized for %d thread%s per core\n",
439 tpc, tpc > 1 ? "s" : "");
440 printk(KERN_DEBUG " (thread shift is %d)\n", threads_shift);
445 * setup_cpu_maps - initialize the following cpu maps:
449 * Having the possible map set up early allows us to restrict allocations
450 * of things like irqstacks to nr_cpu_ids rather than NR_CPUS.
452 * We do not initialize the online map here; cpus set their own bits in
453 * cpu_online_mask as they come up.
455 * This function is valid only for Open Firmware systems. finish_device_tree
456 * must be called before using this.
458 * While we're here, we may as well set the "physical" cpu ids in the paca.
460 * NOTE: This must match the parsing done in early_init_dt_scan_cpus.
462 void __init smp_setup_cpu_maps(void)
464 struct device_node *dn = NULL;
468 DBG("smp_setup_cpu_maps()\n");
470 while ((dn = of_find_node_by_type(dn, "cpu")) && cpu < nr_cpu_ids) {
471 const __be32 *intserv;
475 DBG(" * %s...\n", dn->full_name);
477 intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s",
480 DBG(" ibm,ppc-interrupt-server#s -> %d threads\n",
483 DBG(" no ibm,ppc-interrupt-server#s -> 1 thread\n");
484 intserv = of_get_property(dn, "reg", &len);
486 cpu_be = cpu_to_be32(cpu);
487 intserv = &cpu_be; /* assume logical == phys */
492 nthreads = len / sizeof(int);
494 for (j = 0; j < nthreads && cpu < nr_cpu_ids; j++) {
497 DBG(" thread %d -> cpu %d (hard id %d)\n",
498 j, cpu, be32_to_cpu(intserv[j]));
500 avail = of_device_is_available(dn);
502 avail = !of_property_match_string(dn,
503 "enable-method", "spin-table");
505 set_cpu_present(cpu, avail);
506 set_hard_smp_processor_id(cpu, be32_to_cpu(intserv[j]));
507 set_cpu_possible(cpu, true);
512 /* If no SMT supported, nthreads is forced to 1 */
513 if (!cpu_has_feature(CPU_FTR_SMT)) {
514 DBG(" SMT disabled ! nthreads forced to 1\n");
520 * On pSeries LPAR, we need to know how many cpus
521 * could possibly be added to this partition.
523 if (firmware_has_feature(FW_FEATURE_LPAR) &&
524 (dn = of_find_node_by_path("/rtas"))) {
525 int num_addr_cell, num_size_cell, maxcpus;
528 num_addr_cell = of_n_addr_cells(dn);
529 num_size_cell = of_n_size_cells(dn);
531 ireg = of_get_property(dn, "ibm,lrdr-capacity", NULL);
536 maxcpus = be32_to_cpup(ireg + num_addr_cell + num_size_cell);
538 /* Double maxcpus for processors which have SMT capability */
539 if (cpu_has_feature(CPU_FTR_SMT))
542 if (maxcpus > nr_cpu_ids) {
544 "Partition configured for %d cpus, "
545 "operating system maximum is %d.\n",
546 maxcpus, nr_cpu_ids);
547 maxcpus = nr_cpu_ids;
549 printk(KERN_INFO "Partition configured for %d cpus.\n",
552 for (cpu = 0; cpu < maxcpus; cpu++)
553 set_cpu_possible(cpu, true);
557 vdso_data->processorCount = num_present_cpus();
558 #endif /* CONFIG_PPC64 */
560 /* Initialize CPU <=> thread mapping/
562 * WARNING: We assume that the number of threads is the same for
563 * every CPU in the system. If that is not the case, then some code
564 * here will have to be reworked
566 cpu_init_thread_core_maps(nthreads);
568 /* Now that possible cpus are set, set nr_cpu_ids for later use */
573 #endif /* CONFIG_SMP */
575 #ifdef CONFIG_PCSPKR_PLATFORM
576 static __init int add_pcspkr(void)
578 struct device_node *np;
579 struct platform_device *pd;
582 np = of_find_compatible_node(NULL, NULL, "pnpPNP,100");
587 pd = platform_device_alloc("pcspkr", -1);
591 ret = platform_device_add(pd);
593 platform_device_put(pd);
597 device_initcall(add_pcspkr);
598 #endif /* CONFIG_PCSPKR_PLATFORM */
600 void probe_machine(void)
602 extern struct machdep_calls __machine_desc_start;
603 extern struct machdep_calls __machine_desc_end;
607 * Iterate all ppc_md structures until we find the proper
608 * one for the current machine type
610 DBG("Probing machine type ...\n");
613 * Check ppc_md is empty, if not we have a bug, ie, we setup an
614 * entry before probe_machine() which will be overwritten
616 for (i = 0; i < (sizeof(ppc_md) / sizeof(void *)); i++) {
617 if (((void **)&ppc_md)[i]) {
618 printk(KERN_ERR "Entry %d in ppc_md non empty before"
619 " machine probe !\n", i);
623 for (machine_id = &__machine_desc_start;
624 machine_id < &__machine_desc_end;
626 DBG(" %s ...", machine_id->name);
627 memcpy(&ppc_md, machine_id, sizeof(struct machdep_calls));
628 if (ppc_md.probe()) {
634 /* What can we do if we didn't find ? */
635 if (machine_id >= &__machine_desc_end) {
636 DBG("No suitable machine found !\n");
640 printk(KERN_INFO "Using %s machine description\n", ppc_md.name);
643 /* Match a class of boards, not a specific device configuration. */
644 int check_legacy_ioport(unsigned long base_port)
646 struct device_node *parent, *np = NULL;
651 if (!(np = of_find_compatible_node(NULL, NULL, "pnpPNP,303")))
652 np = of_find_compatible_node(NULL, NULL, "pnpPNP,f03");
654 parent = of_get_parent(np);
656 of_i8042_kbd_irq = irq_of_parse_and_map(parent, 0);
657 if (!of_i8042_kbd_irq)
658 of_i8042_kbd_irq = 1;
660 of_i8042_aux_irq = irq_of_parse_and_map(parent, 1);
661 if (!of_i8042_aux_irq)
662 of_i8042_aux_irq = 12;
668 np = of_find_node_by_type(NULL, "8042");
669 /* Pegasos has no device_type on its 8042 node, look for the
672 np = of_find_node_by_name(NULL, "8042");
674 of_i8042_kbd_irq = 1;
675 of_i8042_aux_irq = 12;
678 case FDC_BASE: /* FDC1 */
679 np = of_find_node_by_type(NULL, "fdc");
682 /* ipmi is supposed to fail here */
687 parent = of_get_parent(np);
689 if (strcmp(parent->type, "isa") == 0)
696 EXPORT_SYMBOL(check_legacy_ioport);
698 static int ppc_panic_event(struct notifier_block *this,
699 unsigned long event, void *ptr)
702 * If firmware-assisted dump has been registered then trigger
703 * firmware-assisted dump and let firmware handle everything else.
705 crash_fadump(NULL, ptr);
706 ppc_md.panic(ptr); /* May not return */
710 static struct notifier_block ppc_panic_block = {
711 .notifier_call = ppc_panic_event,
712 .priority = INT_MIN /* may not return; must be done last */
715 void __init setup_panic(void)
719 atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
722 #ifdef CONFIG_CHECK_CACHE_COHERENCY
724 * For platforms that have configurable cache-coherency. This function
725 * checks that the cache coherency setting of the kernel matches the setting
726 * left by the firmware, as indicated in the device tree. Since a mismatch
727 * will eventually result in DMA failures, we print * and error and call
728 * BUG() in that case.
731 #ifdef CONFIG_NOT_COHERENT_CACHE
732 #define KERNEL_COHERENCY 0
734 #define KERNEL_COHERENCY 1
737 static int __init check_cache_coherency(void)
739 struct device_node *np;
741 int devtree_coherency;
743 np = of_find_node_by_path("/");
744 prop = of_get_property(np, "coherency-off", NULL);
747 devtree_coherency = prop ? 0 : 1;
749 if (devtree_coherency != KERNEL_COHERENCY) {
751 "kernel coherency:%s != device tree_coherency:%s\n",
752 KERNEL_COHERENCY ? "on" : "off",
753 devtree_coherency ? "on" : "off");
760 late_initcall(check_cache_coherency);
761 #endif /* CONFIG_CHECK_CACHE_COHERENCY */
763 #ifdef CONFIG_DEBUG_FS
764 struct dentry *powerpc_debugfs_root;
765 EXPORT_SYMBOL(powerpc_debugfs_root);
767 static int powerpc_debugfs_init(void)
769 powerpc_debugfs_root = debugfs_create_dir("powerpc", NULL);
771 return powerpc_debugfs_root == NULL;
773 arch_initcall(powerpc_debugfs_init);
776 void ppc_printk_progress(char *s, unsigned short hex)
781 void arch_setup_pdev_archdata(struct platform_device *pdev)
783 pdev->archdata.dma_mask = DMA_BIT_MASK(32);
784 pdev->dev.dma_mask = &pdev->archdata.dma_mask;
785 set_dma_ops(&pdev->dev, &dma_direct_ops);
788 static __init void print_system_info(void)
790 pr_info("-----------------------------------------------------\n");
791 #ifdef CONFIG_PPC_STD_MMU_64
792 pr_info("ppc64_pft_size = 0x%llx\n", ppc64_pft_size);
794 #ifdef CONFIG_PPC_STD_MMU_32
795 pr_info("Hash_size = 0x%lx\n", Hash_size);
797 pr_info("phys_mem_size = 0x%llx\n",
798 (unsigned long long)memblock_phys_mem_size());
800 pr_info("dcache_bsize = 0x%x\n", dcache_bsize);
801 pr_info("icache_bsize = 0x%x\n", icache_bsize);
802 if (ucache_bsize != 0)
803 pr_info("ucache_bsize = 0x%x\n", ucache_bsize);
805 pr_info("cpu_features = 0x%016lx\n", cur_cpu_spec->cpu_features);
806 pr_info(" possible = 0x%016lx\n",
807 (unsigned long)CPU_FTRS_POSSIBLE);
808 pr_info(" always = 0x%016lx\n",
809 (unsigned long)CPU_FTRS_ALWAYS);
810 pr_info("cpu_user_features = 0x%08x 0x%08x\n",
811 cur_cpu_spec->cpu_user_features,
812 cur_cpu_spec->cpu_user_features2);
813 pr_info("mmu_features = 0x%08x\n", cur_cpu_spec->mmu_features);
815 pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
818 #ifdef CONFIG_PPC_STD_MMU_64
820 pr_info("htab_address = 0x%p\n", htab_address);
822 pr_info("htab_hash_mask = 0x%lx\n", htab_hash_mask);
824 #ifdef CONFIG_PPC_STD_MMU_32
826 pr_info("Hash = 0x%p\n", Hash);
828 pr_info("Hash_mask = 0x%lx\n", Hash_mask);
831 if (PHYSICAL_START > 0)
832 pr_info("physical_start = 0x%llx\n",
833 (unsigned long long)PHYSICAL_START);
834 pr_info("-----------------------------------------------------\n");
838 * Called into from start_kernel this initializes memblock, which is used
839 * to manage page allocation until mem_init is called.
841 void __init setup_arch(char **cmdline_p)
843 *cmdline_p = boot_command_line;
845 /* Set a half-reasonable default so udelay does something sensible */
846 loops_per_jiffy = 500000000 / HZ;
848 /* Unflatten the device-tree passed by prom_init or kexec */
849 unflatten_device_tree();
852 * Initialize cache line/block info from device-tree (on ppc64) or
853 * just cputable (on ppc32).
855 initialize_cache_info();
857 /* Initialize RTAS if available. */
860 /* Check if we have an initrd provided via the device-tree. */
863 /* Probe the machine type, establish ppc_md. */
866 /* Setup panic notifier if requested by the platform. */
870 * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
871 * it from their respective probe() function.
875 /* Discover standard serial ports. */
876 find_legacy_serial_ports();
878 /* Register early console with the printk subsystem. */
879 register_early_udbg_console();
881 /* Setup the various CPU maps based on the device-tree. */
882 smp_setup_cpu_maps();
884 /* Initialize xmon. */
887 /* Check the SMT related command line arguments (ppc64). */
890 /* On BookE, setup per-core TLB data structures. */
891 setup_tlb_core_data();
894 * Release secondary cpus out of their spinloops at 0x60 now that
895 * we can map physical -> logical CPU ids.
897 * Freescale Book3e parts spin in a loop provided by firmware,
898 * so smp_release_cpus() does nothing for them.
904 /* Print various info about the machine that has been gathered so far. */
907 /* Reserve large chunks of memory for use by CMA for KVM. */
911 * Reserve any gigantic pages requested on the command line.
912 * memblock needs to have been initialized by the time this is
913 * called since this will reserve memory.
915 reserve_hugetlb_gpages();
917 klp_init_thread_info(&init_thread_info);
919 init_mm.start_code = (unsigned long)_stext;
920 init_mm.end_code = (unsigned long) _etext;
921 init_mm.end_data = (unsigned long) _edata;
922 init_mm.brk = klimit;
923 #ifdef CONFIG_PPC_64K_PAGES
924 init_mm.context.pte_frag = NULL;
926 #ifdef CONFIG_SPAPR_TCE_IOMMU
927 mm_iommu_init(&init_mm);
929 irqstack_early_init();
930 exc_lvl_early_init();
931 emergency_stack_init();
935 #ifdef CONFIG_DUMMY_CONSOLE
936 conswitchp = &dummy_con;
938 if (ppc_md.setup_arch)
943 /* Initialize the MMU context management stuff. */
947 /* Interrupt code needs to be 64K-aligned. */
948 if ((unsigned long)_stext & 0xffff)
949 panic("Kernelbase not 64K-aligned (0x%lx)!\n",
950 (unsigned long)_stext);