3 * Common boot and setup code.
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/config.h>
16 #include <linux/module.h>
17 #include <linux/string.h>
18 #include <linux/sched.h>
19 #include <linux/init.h>
20 #include <linux/kernel.h>
21 #include <linux/reboot.h>
22 #include <linux/delay.h>
23 #include <linux/initrd.h>
24 #include <linux/ide.h>
25 #include <linux/seq_file.h>
26 #include <linux/ioport.h>
27 #include <linux/console.h>
28 #include <linux/utsname.h>
29 #include <linux/tty.h>
30 #include <linux/root_dev.h>
31 #include <linux/notifier.h>
32 #include <linux/cpu.h>
33 #include <linux/unistd.h>
34 #include <linux/serial.h>
35 #include <linux/serial_8250.h>
36 #include <linux/bootmem.h>
38 #include <asm/kdump.h>
40 #include <asm/processor.h>
41 #include <asm/pgtable.h>
44 #include <asm/machdep.h>
47 #include <asm/cputable.h>
48 #include <asm/sections.h>
49 #include <asm/btext.h>
50 #include <asm/nvram.h>
51 #include <asm/setup.h>
52 #include <asm/system.h>
54 #include <asm/iommu.h>
55 #include <asm/serial.h>
56 #include <asm/cache.h>
60 #include <asm/iseries/it_lp_naca.h>
61 #include <asm/firmware.h>
64 #include <asm/kexec.h>
69 #define DBG(fmt...) udbg_printf(fmt)
79 /* Pick defaults since we might want to patch instructions
80 * before we've read this from the device tree.
82 struct ppc64_caches ppc64_caches = {
88 EXPORT_SYMBOL_GPL(ppc64_caches);
91 * These are used in binfmt_elf.c to put aux entries on the stack
92 * for each elf executable being started.
98 #ifdef CONFIG_MAGIC_SYSRQ
99 unsigned long SYSRQ_KEY;
100 #endif /* CONFIG_MAGIC_SYSRQ */
103 static int ppc64_panic_event(struct notifier_block *, unsigned long, void *);
104 static struct notifier_block ppc64_panic_block = {
105 .notifier_call = ppc64_panic_event,
106 .priority = INT_MIN /* may not return; must be done last */
111 static int smt_enabled_cmdline;
113 /* Look for ibm,smt-enabled OF option */
114 static void check_smt_enabled(void)
116 struct device_node *dn;
119 /* Allow the command line to overrule the OF option */
120 if (smt_enabled_cmdline)
123 dn = of_find_node_by_path("/options");
126 smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
129 if (!strcmp(smt_option, "on"))
130 smt_enabled_at_boot = 1;
131 else if (!strcmp(smt_option, "off"))
132 smt_enabled_at_boot = 0;
137 /* Look for smt-enabled= cmdline option */
138 static int __init early_smt_enabled(char *p)
140 smt_enabled_cmdline = 1;
145 if (!strcmp(p, "on") || !strcmp(p, "1"))
146 smt_enabled_at_boot = 1;
147 else if (!strcmp(p, "off") || !strcmp(p, "0"))
148 smt_enabled_at_boot = 0;
152 early_param("smt-enabled", early_smt_enabled);
155 #define check_smt_enabled()
156 #endif /* CONFIG_SMP */
159 * Early initialization entry point. This is called by head.S
160 * with MMU translation disabled. We rely on the "feature" of
161 * the CPU that ignores the top 2 bits of the address in real
162 * mode so we can access kernel globals normally provided we
163 * only toy with things in the RMO region. From here, we do
164 * some early parsing of the device-tree to setup out LMB
165 * data structures, and allocate & initialize the hash table
166 * and segment tables so we can start running with translation
169 * It is this function which will call the probe() callback of
170 * the various platform types and copy the matching one to the
171 * global ppc_md structure. Your platform can eventually do
172 * some very early initializations from the probe() routine, but
173 * this is not recommended, be very careful as, for example, the
174 * device-tree is not accessible via normal means at this point.
177 void __init early_setup(unsigned long dt_ptr)
179 /* Enable early debugging if any specified (see udbg.h) */
182 DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
185 * Do early initializations using the flattened device
186 * tree, like retreiving the physical memory map or
187 * calculating/retreiving the hash table size
189 early_init_devtree(__va(dt_ptr));
191 /* Now we know the logical id of our boot cpu, setup the paca. */
194 /* Fix up paca fields required for the boot cpu */
195 get_paca()->cpu_start = 1;
196 get_paca()->stab_real = __pa((u64)&initial_stab);
197 get_paca()->stab_addr = (u64)&initial_stab;
199 /* Probe the machine type */
202 #ifdef CONFIG_CRASH_DUMP
206 DBG("Found, Initializing memory management...\n");
209 * Initialize the MMU Hash table and create the linear mapping
210 * of memory. Has to be done before stab/slb initialization as
211 * this is currently where the page size encoding is obtained
216 * Initialize stab / SLB management except on iSeries
218 if (cpu_has_feature(CPU_FTR_SLB))
220 else if (!firmware_has_feature(FW_FEATURE_ISERIES))
221 stab_initialize(get_paca()->stab_real);
223 DBG(" <- early_setup()\n");
227 void early_setup_secondary(void)
229 struct paca_struct *lpaca = get_paca();
231 /* Mark enabled in PACA */
232 lpaca->proc_enabled = 0;
234 /* Initialize hash table for that CPU */
235 htab_initialize_secondary();
237 /* Initialize STAB/SLB. We use a virtual address as it works
238 * in real mode on pSeries and we want a virutal address on
241 if (cpu_has_feature(CPU_FTR_SLB))
244 stab_initialize(lpaca->stab_addr);
247 #endif /* CONFIG_SMP */
249 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
250 void smp_release_cpus(void)
252 extern unsigned long __secondary_hold_spinloop;
255 DBG(" -> smp_release_cpus()\n");
257 /* All secondary cpus are spinning on a common spinloop, release them
258 * all now so they can start to spin on their individual paca
259 * spinloops. For non SMP kernels, the secondary cpus never get out
260 * of the common spinloop.
261 * This is useless but harmless on iSeries, secondaries are already
262 * waiting on their paca spinloops. */
264 ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
269 DBG(" <- smp_release_cpus()\n");
271 #endif /* CONFIG_SMP || CONFIG_KEXEC */
274 * Initialize some remaining members of the ppc64_caches and systemcfg
276 * (at least until we get rid of them completely). This is mostly some
277 * cache informations about the CPU that will be used by cache flush
278 * routines and/or provided to userland
280 static void __init initialize_cache_info(void)
282 struct device_node *np;
283 unsigned long num_cpus = 0;
285 DBG(" -> initialize_cache_info()\n");
287 for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
290 /* We're assuming *all* of the CPUs have the same
291 * d-cache and i-cache sizes... -Peter
294 if ( num_cpus == 1 ) {
299 /* Then read cache informations */
300 if (machine_is(powermac)) {
301 dc = "d-cache-block-size";
302 ic = "i-cache-block-size";
304 dc = "d-cache-line-size";
305 ic = "i-cache-line-size";
309 lsize = cur_cpu_spec->dcache_bsize;
310 sizep = (u32 *)get_property(np, "d-cache-size", NULL);
313 lsizep = (u32 *) get_property(np, dc, NULL);
316 if (sizep == 0 || lsizep == 0)
317 DBG("Argh, can't find dcache properties ! "
318 "sizep: %p, lsizep: %p\n", sizep, lsizep);
320 ppc64_caches.dsize = size;
321 ppc64_caches.dline_size = lsize;
322 ppc64_caches.log_dline_size = __ilog2(lsize);
323 ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
326 lsize = cur_cpu_spec->icache_bsize;
327 sizep = (u32 *)get_property(np, "i-cache-size", NULL);
330 lsizep = (u32 *)get_property(np, ic, NULL);
333 if (sizep == 0 || lsizep == 0)
334 DBG("Argh, can't find icache properties ! "
335 "sizep: %p, lsizep: %p\n", sizep, lsizep);
337 ppc64_caches.isize = size;
338 ppc64_caches.iline_size = lsize;
339 ppc64_caches.log_iline_size = __ilog2(lsize);
340 ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
344 DBG(" <- initialize_cache_info()\n");
349 * Do some initial setup of the system. The parameters are those which
350 * were passed in from the bootloader.
352 void __init setup_system(void)
354 DBG(" -> setup_system()\n");
357 kdump_move_device_tree();
360 * Unflatten the device-tree passed by prom_init or kexec
362 unflatten_device_tree();
365 kexec_setup(); /* requires unflattened device tree. */
369 * Fill the ppc64_caches & systemcfg structures with informations
370 * retrieved from the device-tree. Need to be called before
371 * finish_device_tree() since the later requires some of the
372 * informations filled up here to properly parse the interrupt
374 * It also sets up the cache line sizes which allows to call
375 * routines like flush_icache_range (used by the hash init
378 initialize_cache_info();
380 #ifdef CONFIG_PPC_RTAS
382 * Initialize RTAS if available
385 #endif /* CONFIG_PPC_RTAS */
388 * Check if we have an initrd provided via the device-tree
393 * Do some platform specific early initializations, that includes
394 * setting up the hash table pointers. It also sets up some interrupt-mapping
395 * related options that will be used by finish_device_tree()
400 * We can discover serial ports now since the above did setup the
401 * hash table management for us, thus ioremap works. We do that early
402 * so that further code can be debugged
404 find_legacy_serial_ports();
407 * "Finish" the device-tree, that is do the actual parsing of
408 * some of the properties like the interrupt map
410 finish_device_tree();
415 #ifdef CONFIG_XMON_DEFAULT
419 * Register early console
421 register_early_udbg_console();
423 /* Save unparsed command line copy for /proc/cmdline */
424 strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
429 smp_setup_cpu_maps();
432 /* Release secondary cpus out of their spinloops at 0x60 now that
433 * we can map physical -> logical CPU ids
438 printk("Starting Linux PPC64 %s\n", system_utsname.version);
440 printk("-----------------------------------------------------\n");
441 printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size);
442 printk("ppc64_interrupt_controller = 0x%ld\n",
443 ppc64_interrupt_controller);
444 printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
445 printk("ppc64_caches.dcache_line_size = 0x%x\n",
446 ppc64_caches.dline_size);
447 printk("ppc64_caches.icache_line_size = 0x%x\n",
448 ppc64_caches.iline_size);
449 printk("htab_address = 0x%p\n", htab_address);
450 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
451 #if PHYSICAL_START > 0
452 printk("physical_start = 0x%x\n", PHYSICAL_START);
454 printk("-----------------------------------------------------\n");
456 DBG(" <- setup_system()\n");
459 static int ppc64_panic_event(struct notifier_block *this,
460 unsigned long event, void *ptr)
462 ppc_md.panic((char *)ptr); /* May not return */
466 #ifdef CONFIG_IRQSTACKS
467 static void __init irqstack_early_init(void)
472 * interrupt stacks must be under 256MB, we cannot afford to take
473 * SLB misses on them.
475 for_each_possible_cpu(i) {
476 softirq_ctx[i] = (struct thread_info *)
477 __va(lmb_alloc_base(THREAD_SIZE,
478 THREAD_SIZE, 0x10000000));
479 hardirq_ctx[i] = (struct thread_info *)
480 __va(lmb_alloc_base(THREAD_SIZE,
481 THREAD_SIZE, 0x10000000));
485 #define irqstack_early_init()
489 * Stack space used when we detect a bad kernel stack pointer, and
490 * early in SMP boots before relocation is enabled.
492 static void __init emergency_stack_init(void)
498 * Emergency stacks must be under 256MB, we cannot afford to take
499 * SLB misses on them. The ABI also requires them to be 128-byte
502 * Since we use these as temporary stacks during secondary CPU
503 * bringup, we need to get at them in real mode. This means they
504 * must also be within the RMO region.
506 limit = min(0x10000000UL, lmb.rmo_size);
508 for_each_possible_cpu(i)
509 paca[i].emergency_sp =
510 __va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
514 * Called into from start_kernel, after lock_kernel has been called.
515 * Initializes bootmem, which is unsed to manage page allocation until
516 * mem_init is called.
518 void __init setup_arch(char **cmdline_p)
520 extern void do_init_bootmem(void);
522 ppc64_boot_msg(0x12, "Setup Arch");
524 *cmdline_p = cmd_line;
527 * Set cache line size based on type of cpu as a default.
528 * Systems with OF can look in the properties on the cpu node(s)
529 * for a possibly more accurate value.
531 dcache_bsize = ppc64_caches.dline_size;
532 icache_bsize = ppc64_caches.iline_size;
534 /* reboot on panic */
538 atomic_notifier_chain_register(&panic_notifier_list,
541 init_mm.start_code = PAGE_OFFSET;
542 init_mm.end_code = (unsigned long) _etext;
543 init_mm.end_data = (unsigned long) _edata;
544 init_mm.brk = klimit;
546 irqstack_early_init();
547 emergency_stack_init();
551 /* set up the bootmem stuff with available memory */
555 #ifdef CONFIG_DUMMY_CONSOLE
556 conswitchp = &dummy_con;
562 ppc64_boot_msg(0x15, "Setup Done");
566 /* ToDo: do something useful if ppc_md is not yet setup. */
567 #define PPC64_LINUX_FUNCTION 0x0f000000
568 #define PPC64_IPL_MESSAGE 0xc0000000
569 #define PPC64_TERM_MESSAGE 0xb0000000
571 static void ppc64_do_msg(unsigned int src, const char *msg)
573 if (ppc_md.progress) {
576 sprintf(buf, "%08X\n", src);
577 ppc_md.progress(buf, 0);
578 snprintf(buf, 128, "%s", msg);
579 ppc_md.progress(buf, 0);
583 /* Print a boot progress message. */
584 void ppc64_boot_msg(unsigned int src, const char *msg)
586 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
587 printk("[boot]%04x %s\n", src, msg);
590 /* Print a termination message (print only -- does not stop the kernel) */
591 void ppc64_terminate_msg(unsigned int src, const char *msg)
593 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
594 printk("[terminate]%04x %s\n", src, msg);
604 void __init setup_per_cpu_areas(void)
610 /* Copy section for each CPU (we discard the original) */
611 size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
612 #ifdef CONFIG_MODULES
613 if (size < PERCPU_ENOUGH_ROOM)
614 size = PERCPU_ENOUGH_ROOM;
617 for_each_possible_cpu(i) {
618 ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
620 panic("Cannot allocate cpu data for CPU %d\n", i);
622 paca[i].data_offset = ptr - __per_cpu_start;
623 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);