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/module.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/seq_file.h>
24 #include <linux/ioport.h>
25 #include <linux/console.h>
26 #include <linux/utsname.h>
27 #include <linux/tty.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/bootmem.h>
35 #include <linux/pci.h>
36 #include <linux/lockdep.h>
37 #include <linux/lmb.h>
39 #include <asm/kdump.h>
41 #include <asm/processor.h>
42 #include <asm/pgtable.h>
45 #include <asm/machdep.h>
48 #include <asm/cputable.h>
49 #include <asm/sections.h>
50 #include <asm/btext.h>
51 #include <asm/nvram.h>
52 #include <asm/setup.h>
53 #include <asm/system.h>
55 #include <asm/iommu.h>
56 #include <asm/serial.h>
57 #include <asm/cache.h>
60 #include <asm/firmware.h>
63 #include <asm/kexec.h>
68 #define DBG(fmt...) udbg_printf(fmt)
77 /* Pick defaults since we might want to patch instructions
78 * before we've read this from the device tree.
80 struct ppc64_caches ppc64_caches = {
86 EXPORT_SYMBOL_GPL(ppc64_caches);
89 extern void _mcount(void);
90 EXPORT_SYMBOL(_mcount);
94 * These are used in binfmt_elf.c to put aux entries on the stack
95 * for each elf executable being started.
103 static int smt_enabled_cmdline;
105 /* Look for ibm,smt-enabled OF option */
106 static void check_smt_enabled(void)
108 struct device_node *dn;
109 const char *smt_option;
111 /* Allow the command line to overrule the OF option */
112 if (smt_enabled_cmdline)
115 dn = of_find_node_by_path("/options");
118 smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
121 if (!strcmp(smt_option, "on"))
122 smt_enabled_at_boot = 1;
123 else if (!strcmp(smt_option, "off"))
124 smt_enabled_at_boot = 0;
129 /* Look for smt-enabled= cmdline option */
130 static int __init early_smt_enabled(char *p)
132 smt_enabled_cmdline = 1;
137 if (!strcmp(p, "on") || !strcmp(p, "1"))
138 smt_enabled_at_boot = 1;
139 else if (!strcmp(p, "off") || !strcmp(p, "0"))
140 smt_enabled_at_boot = 0;
144 early_param("smt-enabled", early_smt_enabled);
147 #define check_smt_enabled()
148 #endif /* CONFIG_SMP */
150 /* Put the paca pointer into r13 and SPRG3 */
151 void __init setup_paca(int cpu)
153 local_paca = &paca[cpu];
154 mtspr(SPRN_SPRG3, local_paca);
158 * Early initialization entry point. This is called by head.S
159 * with MMU translation disabled. We rely on the "feature" of
160 * the CPU that ignores the top 2 bits of the address in real
161 * mode so we can access kernel globals normally provided we
162 * only toy with things in the RMO region. From here, we do
163 * some early parsing of the device-tree to setup out LMB
164 * data structures, and allocate & initialize the hash table
165 * and segment tables so we can start running with translation
168 * It is this function which will call the probe() callback of
169 * the various platform types and copy the matching one to the
170 * global ppc_md structure. Your platform can eventually do
171 * some very early initializations from the probe() routine, but
172 * this is not recommended, be very careful as, for example, the
173 * device-tree is not accessible via normal means at this point.
176 void __init early_setup(unsigned long dt_ptr)
178 /* -------- printk is _NOT_ safe to use here ! ------- */
180 /* Fill in any unititialised pacas */
183 /* Identify CPU type */
184 identify_cpu(0, mfspr(SPRN_PVR));
186 /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
189 /* Initialize lockdep early or else spinlocks will blow */
192 /* -------- printk is now safe to use ------- */
194 /* Enable early debugging if any specified (see udbg.h) */
197 DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
200 * Do early initialization using the flattened device
201 * tree, such as retrieving the physical memory map or
202 * calculating/retrieving the hash table size.
204 early_init_devtree(__va(dt_ptr));
206 /* Now we know the logical id of our boot cpu, setup the paca. */
207 setup_paca(boot_cpuid);
209 /* Fix up paca fields required for the boot cpu */
210 get_paca()->cpu_start = 1;
211 get_paca()->stab_real = __pa((u64)&initial_stab);
212 get_paca()->stab_addr = (u64)&initial_stab;
214 /* Probe the machine type */
217 setup_kdump_trampoline();
219 DBG("Found, Initializing memory management...\n");
222 * Initialize the MMU Hash table and create the linear mapping
223 * of memory. Has to be done before stab/slb initialization as
224 * this is currently where the page size encoding is obtained
229 * Initialize stab / SLB management except on iSeries
231 if (cpu_has_feature(CPU_FTR_SLB))
233 else if (!firmware_has_feature(FW_FEATURE_ISERIES))
234 stab_initialize(get_paca()->stab_real);
236 DBG(" <- early_setup()\n");
240 void early_setup_secondary(void)
242 struct paca_struct *lpaca = get_paca();
244 /* Mark interrupts enabled in PACA */
245 lpaca->soft_enabled = 0;
247 /* Initialize hash table for that CPU */
248 htab_initialize_secondary();
250 /* Initialize STAB/SLB. We use a virtual address as it works
251 * in real mode on pSeries and we want a virutal address on
254 if (cpu_has_feature(CPU_FTR_SLB))
257 stab_initialize(lpaca->stab_addr);
260 #endif /* CONFIG_SMP */
262 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
263 void smp_release_cpus(void)
265 extern unsigned long __secondary_hold_spinloop;
268 DBG(" -> smp_release_cpus()\n");
270 /* All secondary cpus are spinning on a common spinloop, release them
271 * all now so they can start to spin on their individual paca
272 * spinloops. For non SMP kernels, the secondary cpus never get out
273 * of the common spinloop.
274 * This is useless but harmless on iSeries, secondaries are already
275 * waiting on their paca spinloops. */
277 ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
282 DBG(" <- smp_release_cpus()\n");
284 #endif /* CONFIG_SMP || CONFIG_KEXEC */
287 * Initialize some remaining members of the ppc64_caches and systemcfg
289 * (at least until we get rid of them completely). This is mostly some
290 * cache informations about the CPU that will be used by cache flush
291 * routines and/or provided to userland
293 static void __init initialize_cache_info(void)
295 struct device_node *np;
296 unsigned long num_cpus = 0;
298 DBG(" -> initialize_cache_info()\n");
300 for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
303 /* We're assuming *all* of the CPUs have the same
304 * d-cache and i-cache sizes... -Peter
307 if ( num_cpus == 1 ) {
308 const u32 *sizep, *lsizep;
312 lsize = cur_cpu_spec->dcache_bsize;
313 sizep = of_get_property(np, "d-cache-size", NULL);
316 lsizep = of_get_property(np, "d-cache-block-size", NULL);
317 /* fallback if block size missing */
319 lsizep = of_get_property(np, "d-cache-line-size", NULL);
322 if (sizep == 0 || lsizep == 0)
323 DBG("Argh, can't find dcache properties ! "
324 "sizep: %p, lsizep: %p\n", sizep, lsizep);
326 ppc64_caches.dsize = size;
327 ppc64_caches.dline_size = lsize;
328 ppc64_caches.log_dline_size = __ilog2(lsize);
329 ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
332 lsize = cur_cpu_spec->icache_bsize;
333 sizep = of_get_property(np, "i-cache-size", NULL);
336 lsizep = of_get_property(np, "i-cache-block-size", NULL);
338 lsizep = of_get_property(np, "i-cache-line-size", NULL);
341 if (sizep == 0 || lsizep == 0)
342 DBG("Argh, can't find icache properties ! "
343 "sizep: %p, lsizep: %p\n", sizep, lsizep);
345 ppc64_caches.isize = size;
346 ppc64_caches.iline_size = lsize;
347 ppc64_caches.log_iline_size = __ilog2(lsize);
348 ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
352 DBG(" <- initialize_cache_info()\n");
357 * Do some initial setup of the system. The parameters are those which
358 * were passed in from the bootloader.
360 void __init setup_system(void)
362 DBG(" -> setup_system()\n");
364 /* Apply the CPUs-specific and firmware specific fixups to kernel
365 * text (nop out sections not relevant to this CPU or this firmware)
367 do_feature_fixups(cur_cpu_spec->cpu_features,
368 &__start___ftr_fixup, &__stop___ftr_fixup);
369 do_feature_fixups(powerpc_firmware_features,
370 &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
373 * Unflatten the device-tree passed by prom_init or kexec
375 unflatten_device_tree();
378 * Fill the ppc64_caches & systemcfg structures with informations
379 * retrieved from the device-tree.
381 initialize_cache_info();
384 * Initialize irq remapping subsystem
388 #ifdef CONFIG_PPC_RTAS
390 * Initialize RTAS if available
393 #endif /* CONFIG_PPC_RTAS */
396 * Check if we have an initrd provided via the device-tree
401 * Do some platform specific early initializations, that includes
402 * setting up the hash table pointers. It also sets up some interrupt-mapping
403 * related options that will be used by finish_device_tree()
405 if (ppc_md.init_early)
409 * We can discover serial ports now since the above did setup the
410 * hash table management for us, thus ioremap works. We do that early
411 * so that further code can be debugged
413 find_legacy_serial_ports();
416 * Register early console
418 register_early_udbg_console();
426 smp_setup_cpu_maps();
429 /* Release secondary cpus out of their spinloops at 0x60 now that
430 * we can map physical -> logical CPU ids
435 printk("Starting Linux PPC64 %s\n", init_utsname()->version);
437 printk("-----------------------------------------------------\n");
438 printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size);
439 printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
440 if (ppc64_caches.dline_size != 0x80)
441 printk("ppc64_caches.dcache_line_size = 0x%x\n",
442 ppc64_caches.dline_size);
443 if (ppc64_caches.iline_size != 0x80)
444 printk("ppc64_caches.icache_line_size = 0x%x\n",
445 ppc64_caches.iline_size);
447 printk("htab_address = 0x%p\n", htab_address);
448 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
449 #if PHYSICAL_START > 0
450 printk("physical_start = 0x%lx\n", PHYSICAL_START);
452 printk("-----------------------------------------------------\n");
454 DBG(" <- setup_system()\n");
457 #ifdef CONFIG_IRQSTACKS
458 static void __init irqstack_early_init(void)
463 * interrupt stacks must be under 256MB, we cannot afford to take
464 * SLB misses on them.
466 for_each_possible_cpu(i) {
467 softirq_ctx[i] = (struct thread_info *)
468 __va(lmb_alloc_base(THREAD_SIZE,
469 THREAD_SIZE, 0x10000000));
470 hardirq_ctx[i] = (struct thread_info *)
471 __va(lmb_alloc_base(THREAD_SIZE,
472 THREAD_SIZE, 0x10000000));
476 #define irqstack_early_init()
480 * Stack space used when we detect a bad kernel stack pointer, and
481 * early in SMP boots before relocation is enabled.
483 static void __init emergency_stack_init(void)
489 * Emergency stacks must be under 256MB, we cannot afford to take
490 * SLB misses on them. The ABI also requires them to be 128-byte
493 * Since we use these as temporary stacks during secondary CPU
494 * bringup, we need to get at them in real mode. This means they
495 * must also be within the RMO region.
497 limit = min(0x10000000UL, lmb.rmo_size);
499 for_each_possible_cpu(i) {
501 sp = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
503 paca[i].emergency_sp = __va(sp);
508 * Called into from start_kernel, after lock_kernel has been called.
509 * Initializes bootmem, which is unsed to manage page allocation until
510 * mem_init is called.
512 void __init setup_arch(char **cmdline_p)
514 ppc64_boot_msg(0x12, "Setup Arch");
516 *cmdline_p = cmd_line;
519 * Set cache line size based on type of cpu as a default.
520 * Systems with OF can look in the properties on the cpu node(s)
521 * for a possibly more accurate value.
523 dcache_bsize = ppc64_caches.dline_size;
524 icache_bsize = ppc64_caches.iline_size;
526 /* reboot on panic */
532 init_mm.start_code = (unsigned long)_stext;
533 init_mm.end_code = (unsigned long) _etext;
534 init_mm.end_data = (unsigned long) _edata;
535 init_mm.brk = klimit;
537 irqstack_early_init();
538 emergency_stack_init();
542 /* set up the bootmem stuff with available memory */
546 #ifdef CONFIG_DUMMY_CONSOLE
547 conswitchp = &dummy_con;
550 if (ppc_md.setup_arch)
554 ppc64_boot_msg(0x15, "Setup Done");
558 /* ToDo: do something useful if ppc_md is not yet setup. */
559 #define PPC64_LINUX_FUNCTION 0x0f000000
560 #define PPC64_IPL_MESSAGE 0xc0000000
561 #define PPC64_TERM_MESSAGE 0xb0000000
563 static void ppc64_do_msg(unsigned int src, const char *msg)
565 if (ppc_md.progress) {
568 sprintf(buf, "%08X\n", src);
569 ppc_md.progress(buf, 0);
570 snprintf(buf, 128, "%s", msg);
571 ppc_md.progress(buf, 0);
575 /* Print a boot progress message. */
576 void ppc64_boot_msg(unsigned int src, const char *msg)
578 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
579 printk("[boot]%04x %s\n", src, msg);
582 /* Print a termination message (print only -- does not stop the kernel) */
583 void ppc64_terminate_msg(unsigned int src, const char *msg)
585 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
586 printk("[terminate]%04x %s\n", src, msg);
596 void __init setup_per_cpu_areas(void)
602 /* Copy section for each CPU (we discard the original) */
603 size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
604 #ifdef CONFIG_MODULES
605 if (size < PERCPU_ENOUGH_ROOM)
606 size = PERCPU_ENOUGH_ROOM;
609 for_each_possible_cpu(i) {
610 ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
612 panic("Cannot allocate cpu data for CPU %d\n", i);
614 paca[i].data_offset = ptr - __per_cpu_start;
615 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
618 /* Now that per_cpu is setup, initialize cpu_sibling_map */
619 smp_setup_cpu_sibling_map();
624 #ifdef CONFIG_PPC_INDIRECT_IO
625 struct ppc_pci_io ppc_pci_io;
626 EXPORT_SYMBOL(ppc_pci_io);
627 #endif /* CONFIG_PPC_INDIRECT_IO */