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/ide.h>
24 #include <linux/seq_file.h>
25 #include <linux/ioport.h>
26 #include <linux/console.h>
27 #include <linux/utsname.h>
28 #include <linux/tty.h>
29 #include <linux/root_dev.h>
30 #include <linux/notifier.h>
31 #include <linux/cpu.h>
32 #include <linux/unistd.h>
33 #include <linux/serial.h>
34 #include <linux/serial_8250.h>
35 #include <linux/bootmem.h>
37 #include <asm/kdump.h>
39 #include <asm/processor.h>
40 #include <asm/pgtable.h>
43 #include <asm/machdep.h>
46 #include <asm/cputable.h>
47 #include <asm/sections.h>
48 #include <asm/btext.h>
49 #include <asm/nvram.h>
50 #include <asm/setup.h>
51 #include <asm/system.h>
53 #include <asm/iommu.h>
54 #include <asm/serial.h>
55 #include <asm/cache.h>
59 #include <asm/firmware.h>
62 #include <asm/kexec.h>
67 #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 * These are used in binfmt_elf.c to put aux entries on the stack
90 * for each elf executable being started.
96 #ifdef CONFIG_MAGIC_SYSRQ
97 unsigned long SYSRQ_KEY;
98 #endif /* CONFIG_MAGIC_SYSRQ */
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 = 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 /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
181 /* Enable early debugging if any specified (see udbg.h) */
184 DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
187 * Do early initializations using the flattened device
188 * tree, like retreiving the physical memory map or
189 * calculating/retreiving the hash table size
191 early_init_devtree(__va(dt_ptr));
193 /* Now we know the logical id of our boot cpu, setup the paca. */
194 setup_paca(boot_cpuid);
196 /* Fix up paca fields required for the boot cpu */
197 get_paca()->cpu_start = 1;
198 get_paca()->stab_real = __pa((u64)&initial_stab);
199 get_paca()->stab_addr = (u64)&initial_stab;
201 /* Probe the machine type */
204 setup_kdump_trampoline();
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 ) {
295 const u32 *sizep, *lsizep;
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 = get_property(np, "d-cache-size", NULL);
313 lsizep = 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 = get_property(np, "i-cache-size", NULL);
330 lsizep = 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 * Unflatten the device-tree passed by prom_init or kexec
359 unflatten_device_tree();
362 * Fill the ppc64_caches & systemcfg structures with informations
363 * retrieved from the device-tree.
365 initialize_cache_info();
368 * Initialize irq remapping subsystem
372 #ifdef CONFIG_PPC_RTAS
374 * Initialize RTAS if available
377 #endif /* CONFIG_PPC_RTAS */
380 * Check if we have an initrd provided via the device-tree
385 * Do some platform specific early initializations, that includes
386 * setting up the hash table pointers. It also sets up some interrupt-mapping
387 * related options that will be used by finish_device_tree()
392 * We can discover serial ports now since the above did setup the
393 * hash table management for us, thus ioremap works. We do that early
394 * so that further code can be debugged
396 find_legacy_serial_ports();
401 #ifdef CONFIG_XMON_DEFAULT
405 * Register early console
407 register_early_udbg_console();
413 smp_setup_cpu_maps();
416 /* Release secondary cpus out of their spinloops at 0x60 now that
417 * we can map physical -> logical CPU ids
422 printk("Starting Linux PPC64 %s\n", system_utsname.version);
424 printk("-----------------------------------------------------\n");
425 printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size);
426 printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
427 printk("ppc64_caches.dcache_line_size = 0x%x\n",
428 ppc64_caches.dline_size);
429 printk("ppc64_caches.icache_line_size = 0x%x\n",
430 ppc64_caches.iline_size);
431 printk("htab_address = 0x%p\n", htab_address);
432 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
433 #if PHYSICAL_START > 0
434 printk("physical_start = 0x%x\n", PHYSICAL_START);
436 printk("-----------------------------------------------------\n");
438 DBG(" <- setup_system()\n");
441 #ifdef CONFIG_IRQSTACKS
442 static void __init irqstack_early_init(void)
447 * interrupt stacks must be under 256MB, we cannot afford to take
448 * SLB misses on them.
450 for_each_possible_cpu(i) {
451 softirq_ctx[i] = (struct thread_info *)
452 __va(lmb_alloc_base(THREAD_SIZE,
453 THREAD_SIZE, 0x10000000));
454 hardirq_ctx[i] = (struct thread_info *)
455 __va(lmb_alloc_base(THREAD_SIZE,
456 THREAD_SIZE, 0x10000000));
460 #define irqstack_early_init()
464 * Stack space used when we detect a bad kernel stack pointer, and
465 * early in SMP boots before relocation is enabled.
467 static void __init emergency_stack_init(void)
473 * Emergency stacks must be under 256MB, we cannot afford to take
474 * SLB misses on them. The ABI also requires them to be 128-byte
477 * Since we use these as temporary stacks during secondary CPU
478 * bringup, we need to get at them in real mode. This means they
479 * must also be within the RMO region.
481 limit = min(0x10000000UL, lmb.rmo_size);
483 for_each_possible_cpu(i)
484 paca[i].emergency_sp =
485 __va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
489 * Called into from start_kernel, after lock_kernel has been called.
490 * Initializes bootmem, which is unsed to manage page allocation until
491 * mem_init is called.
493 void __init setup_arch(char **cmdline_p)
495 ppc64_boot_msg(0x12, "Setup Arch");
497 *cmdline_p = cmd_line;
500 * Set cache line size based on type of cpu as a default.
501 * Systems with OF can look in the properties on the cpu node(s)
502 * for a possibly more accurate value.
504 dcache_bsize = ppc64_caches.dline_size;
505 icache_bsize = ppc64_caches.iline_size;
507 /* reboot on panic */
513 init_mm.start_code = PAGE_OFFSET;
514 init_mm.end_code = (unsigned long) _etext;
515 init_mm.end_data = (unsigned long) _edata;
516 init_mm.brk = klimit;
518 irqstack_early_init();
519 emergency_stack_init();
523 /* set up the bootmem stuff with available memory */
527 #ifdef CONFIG_DUMMY_CONSOLE
528 conswitchp = &dummy_con;
534 ppc64_boot_msg(0x15, "Setup Done");
538 /* ToDo: do something useful if ppc_md is not yet setup. */
539 #define PPC64_LINUX_FUNCTION 0x0f000000
540 #define PPC64_IPL_MESSAGE 0xc0000000
541 #define PPC64_TERM_MESSAGE 0xb0000000
543 static void ppc64_do_msg(unsigned int src, const char *msg)
545 if (ppc_md.progress) {
548 sprintf(buf, "%08X\n", src);
549 ppc_md.progress(buf, 0);
550 snprintf(buf, 128, "%s", msg);
551 ppc_md.progress(buf, 0);
555 /* Print a boot progress message. */
556 void ppc64_boot_msg(unsigned int src, const char *msg)
558 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
559 printk("[boot]%04x %s\n", src, msg);
562 /* Print a termination message (print only -- does not stop the kernel) */
563 void ppc64_terminate_msg(unsigned int src, const char *msg)
565 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
566 printk("[terminate]%04x %s\n", src, msg);
576 void __init setup_per_cpu_areas(void)
582 /* Copy section for each CPU (we discard the original) */
583 size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
584 #ifdef CONFIG_MODULES
585 if (size < PERCPU_ENOUGH_ROOM)
586 size = PERCPU_ENOUGH_ROOM;
589 for_each_possible_cpu(i) {
590 ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
592 panic("Cannot allocate cpu data for CPU %d\n", i);
594 paca[i].data_offset = ptr - __per_cpu_start;
595 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);