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)
76 /* Pick defaults since we might want to patch instructions
77 * before we've read this from the device tree.
79 struct ppc64_caches ppc64_caches = {
85 EXPORT_SYMBOL_GPL(ppc64_caches);
88 * These are used in binfmt_elf.c to put aux entries on the stack
89 * for each elf executable being started.
97 static int smt_enabled_cmdline;
99 /* Look for ibm,smt-enabled OF option */
100 static void check_smt_enabled(void)
102 struct device_node *dn;
103 const char *smt_option;
105 /* Allow the command line to overrule the OF option */
106 if (smt_enabled_cmdline)
109 dn = of_find_node_by_path("/options");
112 smt_option = get_property(dn, "ibm,smt-enabled", NULL);
115 if (!strcmp(smt_option, "on"))
116 smt_enabled_at_boot = 1;
117 else if (!strcmp(smt_option, "off"))
118 smt_enabled_at_boot = 0;
123 /* Look for smt-enabled= cmdline option */
124 static int __init early_smt_enabled(char *p)
126 smt_enabled_cmdline = 1;
131 if (!strcmp(p, "on") || !strcmp(p, "1"))
132 smt_enabled_at_boot = 1;
133 else if (!strcmp(p, "off") || !strcmp(p, "0"))
134 smt_enabled_at_boot = 0;
138 early_param("smt-enabled", early_smt_enabled);
141 #define check_smt_enabled()
142 #endif /* CONFIG_SMP */
144 /* Put the paca pointer into r13 and SPRG3 */
145 void __init setup_paca(int cpu)
147 local_paca = &paca[cpu];
148 mtspr(SPRN_SPRG3, local_paca);
152 * Early initialization entry point. This is called by head.S
153 * with MMU translation disabled. We rely on the "feature" of
154 * the CPU that ignores the top 2 bits of the address in real
155 * mode so we can access kernel globals normally provided we
156 * only toy with things in the RMO region. From here, we do
157 * some early parsing of the device-tree to setup out LMB
158 * data structures, and allocate & initialize the hash table
159 * and segment tables so we can start running with translation
162 * It is this function which will call the probe() callback of
163 * the various platform types and copy the matching one to the
164 * global ppc_md structure. Your platform can eventually do
165 * some very early initializations from the probe() routine, but
166 * this is not recommended, be very careful as, for example, the
167 * device-tree is not accessible via normal means at this point.
170 void __init early_setup(unsigned long dt_ptr)
172 /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
175 /* Enable early debugging if any specified (see udbg.h) */
178 DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
181 * Do early initializations using the flattened device
182 * tree, like retreiving the physical memory map or
183 * calculating/retreiving the hash table size
185 early_init_devtree(__va(dt_ptr));
187 /* Now we know the logical id of our boot cpu, setup the paca. */
188 setup_paca(boot_cpuid);
190 /* Fix up paca fields required for the boot cpu */
191 get_paca()->cpu_start = 1;
192 get_paca()->stab_real = __pa((u64)&initial_stab);
193 get_paca()->stab_addr = (u64)&initial_stab;
195 /* Probe the machine type */
198 setup_kdump_trampoline();
200 DBG("Found, Initializing memory management...\n");
203 * Initialize the MMU Hash table and create the linear mapping
204 * of memory. Has to be done before stab/slb initialization as
205 * this is currently where the page size encoding is obtained
210 * Initialize stab / SLB management except on iSeries
212 if (cpu_has_feature(CPU_FTR_SLB))
214 else if (!firmware_has_feature(FW_FEATURE_ISERIES))
215 stab_initialize(get_paca()->stab_real);
217 DBG(" <- early_setup()\n");
221 void early_setup_secondary(void)
223 struct paca_struct *lpaca = get_paca();
225 /* Mark interrupts enabled in PACA */
226 lpaca->soft_enabled = 0;
228 /* Initialize hash table for that CPU */
229 htab_initialize_secondary();
231 /* Initialize STAB/SLB. We use a virtual address as it works
232 * in real mode on pSeries and we want a virutal address on
235 if (cpu_has_feature(CPU_FTR_SLB))
238 stab_initialize(lpaca->stab_addr);
241 #endif /* CONFIG_SMP */
243 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
244 void smp_release_cpus(void)
246 extern unsigned long __secondary_hold_spinloop;
249 DBG(" -> smp_release_cpus()\n");
251 /* All secondary cpus are spinning on a common spinloop, release them
252 * all now so they can start to spin on their individual paca
253 * spinloops. For non SMP kernels, the secondary cpus never get out
254 * of the common spinloop.
255 * This is useless but harmless on iSeries, secondaries are already
256 * waiting on their paca spinloops. */
258 ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
263 DBG(" <- smp_release_cpus()\n");
265 #endif /* CONFIG_SMP || CONFIG_KEXEC */
268 * Initialize some remaining members of the ppc64_caches and systemcfg
270 * (at least until we get rid of them completely). This is mostly some
271 * cache informations about the CPU that will be used by cache flush
272 * routines and/or provided to userland
274 static void __init initialize_cache_info(void)
276 struct device_node *np;
277 unsigned long num_cpus = 0;
279 DBG(" -> initialize_cache_info()\n");
281 for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
284 /* We're assuming *all* of the CPUs have the same
285 * d-cache and i-cache sizes... -Peter
288 if ( num_cpus == 1 ) {
289 const u32 *sizep, *lsizep;
293 /* Then read cache informations */
294 if (machine_is(powermac)) {
295 dc = "d-cache-block-size";
296 ic = "i-cache-block-size";
298 dc = "d-cache-line-size";
299 ic = "i-cache-line-size";
303 lsize = cur_cpu_spec->dcache_bsize;
304 sizep = get_property(np, "d-cache-size", NULL);
307 lsizep = get_property(np, dc, NULL);
310 if (sizep == 0 || lsizep == 0)
311 DBG("Argh, can't find dcache properties ! "
312 "sizep: %p, lsizep: %p\n", sizep, lsizep);
314 ppc64_caches.dsize = size;
315 ppc64_caches.dline_size = lsize;
316 ppc64_caches.log_dline_size = __ilog2(lsize);
317 ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
320 lsize = cur_cpu_spec->icache_bsize;
321 sizep = get_property(np, "i-cache-size", NULL);
324 lsizep = get_property(np, ic, NULL);
327 if (sizep == 0 || lsizep == 0)
328 DBG("Argh, can't find icache properties ! "
329 "sizep: %p, lsizep: %p\n", sizep, lsizep);
331 ppc64_caches.isize = size;
332 ppc64_caches.iline_size = lsize;
333 ppc64_caches.log_iline_size = __ilog2(lsize);
334 ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
338 DBG(" <- initialize_cache_info()\n");
343 * Do some initial setup of the system. The parameters are those which
344 * were passed in from the bootloader.
346 void __init setup_system(void)
348 DBG(" -> setup_system()\n");
351 * Unflatten the device-tree passed by prom_init or kexec
353 unflatten_device_tree();
356 * Fill the ppc64_caches & systemcfg structures with informations
357 * retrieved from the device-tree.
359 initialize_cache_info();
362 * Initialize irq remapping subsystem
366 #ifdef CONFIG_PPC_RTAS
368 * Initialize RTAS if available
371 #endif /* CONFIG_PPC_RTAS */
374 * Check if we have an initrd provided via the device-tree
379 * Do some platform specific early initializations, that includes
380 * setting up the hash table pointers. It also sets up some interrupt-mapping
381 * related options that will be used by finish_device_tree()
386 * We can discover serial ports now since the above did setup the
387 * hash table management for us, thus ioremap works. We do that early
388 * so that further code can be debugged
390 find_legacy_serial_ports();
393 * Register early console
395 register_early_udbg_console();
403 smp_setup_cpu_maps();
406 /* Release secondary cpus out of their spinloops at 0x60 now that
407 * we can map physical -> logical CPU ids
412 printk("Starting Linux PPC64 %s\n", init_utsname()->version);
414 printk("-----------------------------------------------------\n");
415 printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size);
416 printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
417 printk("ppc64_caches.dcache_line_size = 0x%x\n",
418 ppc64_caches.dline_size);
419 printk("ppc64_caches.icache_line_size = 0x%x\n",
420 ppc64_caches.iline_size);
421 printk("htab_address = 0x%p\n", htab_address);
422 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
423 #if PHYSICAL_START > 0
424 printk("physical_start = 0x%x\n", PHYSICAL_START);
426 printk("-----------------------------------------------------\n");
428 DBG(" <- setup_system()\n");
431 #ifdef CONFIG_IRQSTACKS
432 static void __init irqstack_early_init(void)
437 * interrupt stacks must be under 256MB, we cannot afford to take
438 * SLB misses on them.
440 for_each_possible_cpu(i) {
441 softirq_ctx[i] = (struct thread_info *)
442 __va(lmb_alloc_base(THREAD_SIZE,
443 THREAD_SIZE, 0x10000000));
444 hardirq_ctx[i] = (struct thread_info *)
445 __va(lmb_alloc_base(THREAD_SIZE,
446 THREAD_SIZE, 0x10000000));
450 #define irqstack_early_init()
454 * Stack space used when we detect a bad kernel stack pointer, and
455 * early in SMP boots before relocation is enabled.
457 static void __init emergency_stack_init(void)
463 * Emergency stacks must be under 256MB, we cannot afford to take
464 * SLB misses on them. The ABI also requires them to be 128-byte
467 * Since we use these as temporary stacks during secondary CPU
468 * bringup, we need to get at them in real mode. This means they
469 * must also be within the RMO region.
471 limit = min(0x10000000UL, lmb.rmo_size);
473 for_each_possible_cpu(i)
474 paca[i].emergency_sp =
475 __va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
479 * Called into from start_kernel, after lock_kernel has been called.
480 * Initializes bootmem, which is unsed to manage page allocation until
481 * mem_init is called.
483 void __init setup_arch(char **cmdline_p)
485 ppc64_boot_msg(0x12, "Setup Arch");
487 *cmdline_p = cmd_line;
490 * Set cache line size based on type of cpu as a default.
491 * Systems with OF can look in the properties on the cpu node(s)
492 * for a possibly more accurate value.
494 dcache_bsize = ppc64_caches.dline_size;
495 icache_bsize = ppc64_caches.iline_size;
497 /* reboot on panic */
503 init_mm.start_code = PAGE_OFFSET;
504 init_mm.end_code = (unsigned long) _etext;
505 init_mm.end_data = (unsigned long) _edata;
506 init_mm.brk = klimit;
508 irqstack_early_init();
509 emergency_stack_init();
513 /* set up the bootmem stuff with available memory */
517 #ifdef CONFIG_DUMMY_CONSOLE
518 conswitchp = &dummy_con;
524 ppc64_boot_msg(0x15, "Setup Done");
528 /* ToDo: do something useful if ppc_md is not yet setup. */
529 #define PPC64_LINUX_FUNCTION 0x0f000000
530 #define PPC64_IPL_MESSAGE 0xc0000000
531 #define PPC64_TERM_MESSAGE 0xb0000000
533 static void ppc64_do_msg(unsigned int src, const char *msg)
535 if (ppc_md.progress) {
538 sprintf(buf, "%08X\n", src);
539 ppc_md.progress(buf, 0);
540 snprintf(buf, 128, "%s", msg);
541 ppc_md.progress(buf, 0);
545 /* Print a boot progress message. */
546 void ppc64_boot_msg(unsigned int src, const char *msg)
548 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
549 printk("[boot]%04x %s\n", src, msg);
552 /* Print a termination message (print only -- does not stop the kernel) */
553 void ppc64_terminate_msg(unsigned int src, const char *msg)
555 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
556 printk("[terminate]%04x %s\n", src, msg);
566 void __init setup_per_cpu_areas(void)
572 /* Copy section for each CPU (we discard the original) */
573 size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
574 #ifdef CONFIG_MODULES
575 if (size < PERCPU_ENOUGH_ROOM)
576 size = PERCPU_ENOUGH_ROOM;
579 for_each_possible_cpu(i) {
580 ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
582 panic("Cannot allocate cpu data for CPU %d\n", i);
584 paca[i].data_offset = ptr - __per_cpu_start;
585 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);