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.
98 static int smt_enabled_cmdline
;
100 /* Look for ibm,smt-enabled OF option */
101 static void check_smt_enabled(void)
103 struct device_node
*dn
;
104 const char *smt_option
;
106 /* Allow the command line to overrule the OF option */
107 if (smt_enabled_cmdline
)
110 dn
= of_find_node_by_path("/options");
113 smt_option
= get_property(dn
, "ibm,smt-enabled", NULL
);
116 if (!strcmp(smt_option
, "on"))
117 smt_enabled_at_boot
= 1;
118 else if (!strcmp(smt_option
, "off"))
119 smt_enabled_at_boot
= 0;
124 /* Look for smt-enabled= cmdline option */
125 static int __init
early_smt_enabled(char *p
)
127 smt_enabled_cmdline
= 1;
132 if (!strcmp(p
, "on") || !strcmp(p
, "1"))
133 smt_enabled_at_boot
= 1;
134 else if (!strcmp(p
, "off") || !strcmp(p
, "0"))
135 smt_enabled_at_boot
= 0;
139 early_param("smt-enabled", early_smt_enabled
);
142 #define check_smt_enabled()
143 #endif /* CONFIG_SMP */
145 /* Put the paca pointer into r13 and SPRG3 */
146 void __init
setup_paca(int cpu
)
148 local_paca
= &paca
[cpu
];
149 mtspr(SPRN_SPRG3
, local_paca
);
153 * Early initialization entry point. This is called by head.S
154 * with MMU translation disabled. We rely on the "feature" of
155 * the CPU that ignores the top 2 bits of the address in real
156 * mode so we can access kernel globals normally provided we
157 * only toy with things in the RMO region. From here, we do
158 * some early parsing of the device-tree to setup out LMB
159 * data structures, and allocate & initialize the hash table
160 * and segment tables so we can start running with translation
163 * It is this function which will call the probe() callback of
164 * the various platform types and copy the matching one to the
165 * global ppc_md structure. Your platform can eventually do
166 * some very early initializations from the probe() routine, but
167 * this is not recommended, be very careful as, for example, the
168 * device-tree is not accessible via normal means at this point.
171 void __init
early_setup(unsigned long dt_ptr
)
173 /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
176 /* Enable early debugging if any specified (see udbg.h) */
179 DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr
);
182 * Do early initializations using the flattened device
183 * tree, like retreiving the physical memory map or
184 * calculating/retreiving the hash table size
186 early_init_devtree(__va(dt_ptr
));
188 /* Now we know the logical id of our boot cpu, setup the paca. */
189 setup_paca(boot_cpuid
);
191 /* Fix up paca fields required for the boot cpu */
192 get_paca()->cpu_start
= 1;
193 get_paca()->stab_real
= __pa((u64
)&initial_stab
);
194 get_paca()->stab_addr
= (u64
)&initial_stab
;
196 /* Probe the machine type */
199 setup_kdump_trampoline();
201 DBG("Found, Initializing memory management...\n");
204 * Initialize the MMU Hash table and create the linear mapping
205 * of memory. Has to be done before stab/slb initialization as
206 * this is currently where the page size encoding is obtained
211 * Initialize stab / SLB management except on iSeries
213 if (cpu_has_feature(CPU_FTR_SLB
))
215 else if (!firmware_has_feature(FW_FEATURE_ISERIES
))
216 stab_initialize(get_paca()->stab_real
);
218 DBG(" <- early_setup()\n");
222 void early_setup_secondary(void)
224 struct paca_struct
*lpaca
= get_paca();
226 /* Mark interrupts enabled in PACA */
227 lpaca
->soft_enabled
= 0;
229 /* Initialize hash table for that CPU */
230 htab_initialize_secondary();
232 /* Initialize STAB/SLB. We use a virtual address as it works
233 * in real mode on pSeries and we want a virutal address on
236 if (cpu_has_feature(CPU_FTR_SLB
))
239 stab_initialize(lpaca
->stab_addr
);
242 #endif /* CONFIG_SMP */
244 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
245 void smp_release_cpus(void)
247 extern unsigned long __secondary_hold_spinloop
;
250 DBG(" -> smp_release_cpus()\n");
252 /* All secondary cpus are spinning on a common spinloop, release them
253 * all now so they can start to spin on their individual paca
254 * spinloops. For non SMP kernels, the secondary cpus never get out
255 * of the common spinloop.
256 * This is useless but harmless on iSeries, secondaries are already
257 * waiting on their paca spinloops. */
259 ptr
= (unsigned long *)((unsigned long)&__secondary_hold_spinloop
264 DBG(" <- smp_release_cpus()\n");
266 #endif /* CONFIG_SMP || CONFIG_KEXEC */
269 * Initialize some remaining members of the ppc64_caches and systemcfg
271 * (at least until we get rid of them completely). This is mostly some
272 * cache informations about the CPU that will be used by cache flush
273 * routines and/or provided to userland
275 static void __init
initialize_cache_info(void)
277 struct device_node
*np
;
278 unsigned long num_cpus
= 0;
280 DBG(" -> initialize_cache_info()\n");
282 for (np
= NULL
; (np
= of_find_node_by_type(np
, "cpu"));) {
285 /* We're assuming *all* of the CPUs have the same
286 * d-cache and i-cache sizes... -Peter
289 if ( num_cpus
== 1 ) {
290 const u32
*sizep
, *lsizep
;
294 /* Then read cache informations */
295 if (machine_is(powermac
)) {
296 dc
= "d-cache-block-size";
297 ic
= "i-cache-block-size";
299 dc
= "d-cache-line-size";
300 ic
= "i-cache-line-size";
304 lsize
= cur_cpu_spec
->dcache_bsize
;
305 sizep
= get_property(np
, "d-cache-size", NULL
);
308 lsizep
= get_property(np
, dc
, NULL
);
311 if (sizep
== 0 || lsizep
== 0)
312 DBG("Argh, can't find dcache properties ! "
313 "sizep: %p, lsizep: %p\n", sizep
, lsizep
);
315 ppc64_caches
.dsize
= size
;
316 ppc64_caches
.dline_size
= lsize
;
317 ppc64_caches
.log_dline_size
= __ilog2(lsize
);
318 ppc64_caches
.dlines_per_page
= PAGE_SIZE
/ lsize
;
321 lsize
= cur_cpu_spec
->icache_bsize
;
322 sizep
= get_property(np
, "i-cache-size", NULL
);
325 lsizep
= get_property(np
, ic
, NULL
);
328 if (sizep
== 0 || lsizep
== 0)
329 DBG("Argh, can't find icache properties ! "
330 "sizep: %p, lsizep: %p\n", sizep
, lsizep
);
332 ppc64_caches
.isize
= size
;
333 ppc64_caches
.iline_size
= lsize
;
334 ppc64_caches
.log_iline_size
= __ilog2(lsize
);
335 ppc64_caches
.ilines_per_page
= PAGE_SIZE
/ lsize
;
339 DBG(" <- initialize_cache_info()\n");
344 * Do some initial setup of the system. The parameters are those which
345 * were passed in from the bootloader.
347 void __init
setup_system(void)
349 DBG(" -> setup_system()\n");
352 * Unflatten the device-tree passed by prom_init or kexec
354 unflatten_device_tree();
357 * Fill the ppc64_caches & systemcfg structures with informations
358 * retrieved from the device-tree.
360 initialize_cache_info();
363 * Initialize irq remapping subsystem
367 #ifdef CONFIG_PPC_RTAS
369 * Initialize RTAS if available
372 #endif /* CONFIG_PPC_RTAS */
375 * Check if we have an initrd provided via the device-tree
380 * Do some platform specific early initializations, that includes
381 * setting up the hash table pointers. It also sets up some interrupt-mapping
382 * related options that will be used by finish_device_tree()
387 * We can discover serial ports now since the above did setup the
388 * hash table management for us, thus ioremap works. We do that early
389 * so that further code can be debugged
391 find_legacy_serial_ports();
394 * Register early console
396 register_early_udbg_console();
404 smp_setup_cpu_maps();
407 /* Release secondary cpus out of their spinloops at 0x60 now that
408 * we can map physical -> logical CPU ids
413 printk("Starting Linux PPC64 %s\n", init_utsname()->version
);
415 printk("-----------------------------------------------------\n");
416 printk("ppc64_pft_size = 0x%lx\n", ppc64_pft_size
);
417 printk("physicalMemorySize = 0x%lx\n", lmb_phys_mem_size());
418 printk("ppc64_caches.dcache_line_size = 0x%x\n",
419 ppc64_caches
.dline_size
);
420 printk("ppc64_caches.icache_line_size = 0x%x\n",
421 ppc64_caches
.iline_size
);
422 printk("htab_address = 0x%p\n", htab_address
);
423 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask
);
424 #if PHYSICAL_START > 0
425 printk("physical_start = 0x%x\n", PHYSICAL_START
);
427 printk("-----------------------------------------------------\n");
429 DBG(" <- setup_system()\n");
432 #ifdef CONFIG_IRQSTACKS
433 static void __init
irqstack_early_init(void)
438 * interrupt stacks must be under 256MB, we cannot afford to take
439 * SLB misses on them.
441 for_each_possible_cpu(i
) {
442 softirq_ctx
[i
] = (struct thread_info
*)
443 __va(lmb_alloc_base(THREAD_SIZE
,
444 THREAD_SIZE
, 0x10000000));
445 hardirq_ctx
[i
] = (struct thread_info
*)
446 __va(lmb_alloc_base(THREAD_SIZE
,
447 THREAD_SIZE
, 0x10000000));
451 #define irqstack_early_init()
455 * Stack space used when we detect a bad kernel stack pointer, and
456 * early in SMP boots before relocation is enabled.
458 static void __init
emergency_stack_init(void)
464 * Emergency stacks must be under 256MB, we cannot afford to take
465 * SLB misses on them. The ABI also requires them to be 128-byte
468 * Since we use these as temporary stacks during secondary CPU
469 * bringup, we need to get at them in real mode. This means they
470 * must also be within the RMO region.
472 limit
= min(0x10000000UL
, lmb
.rmo_size
);
474 for_each_possible_cpu(i
)
475 paca
[i
].emergency_sp
=
476 __va(lmb_alloc_base(HW_PAGE_SIZE
, 128, limit
)) + HW_PAGE_SIZE
;
480 * Called into from start_kernel, after lock_kernel has been called.
481 * Initializes bootmem, which is unsed to manage page allocation until
482 * mem_init is called.
484 void __init
setup_arch(char **cmdline_p
)
486 ppc64_boot_msg(0x12, "Setup Arch");
488 *cmdline_p
= cmd_line
;
491 * Set cache line size based on type of cpu as a default.
492 * Systems with OF can look in the properties on the cpu node(s)
493 * for a possibly more accurate value.
495 dcache_bsize
= ppc64_caches
.dline_size
;
496 icache_bsize
= ppc64_caches
.iline_size
;
498 /* reboot on panic */
504 init_mm
.start_code
= PAGE_OFFSET
;
505 init_mm
.end_code
= (unsigned long) _etext
;
506 init_mm
.end_data
= (unsigned long) _edata
;
507 init_mm
.brk
= klimit
;
509 irqstack_early_init();
510 emergency_stack_init();
514 /* set up the bootmem stuff with available memory */
518 #ifdef CONFIG_DUMMY_CONSOLE
519 conswitchp
= &dummy_con
;
525 ppc64_boot_msg(0x15, "Setup Done");
529 /* ToDo: do something useful if ppc_md is not yet setup. */
530 #define PPC64_LINUX_FUNCTION 0x0f000000
531 #define PPC64_IPL_MESSAGE 0xc0000000
532 #define PPC64_TERM_MESSAGE 0xb0000000
534 static void ppc64_do_msg(unsigned int src
, const char *msg
)
536 if (ppc_md
.progress
) {
539 sprintf(buf
, "%08X\n", src
);
540 ppc_md
.progress(buf
, 0);
541 snprintf(buf
, 128, "%s", msg
);
542 ppc_md
.progress(buf
, 0);
546 /* Print a boot progress message. */
547 void ppc64_boot_msg(unsigned int src
, const char *msg
)
549 ppc64_do_msg(PPC64_LINUX_FUNCTION
|PPC64_IPL_MESSAGE
|src
, msg
);
550 printk("[boot]%04x %s\n", src
, msg
);
553 /* Print a termination message (print only -- does not stop the kernel) */
554 void ppc64_terminate_msg(unsigned int src
, const char *msg
)
556 ppc64_do_msg(PPC64_LINUX_FUNCTION
|PPC64_TERM_MESSAGE
|src
, msg
);
557 printk("[terminate]%04x %s\n", src
, msg
);
567 void __init
setup_per_cpu_areas(void)
573 /* Copy section for each CPU (we discard the original) */
574 size
= ALIGN(__per_cpu_end
- __per_cpu_start
, SMP_CACHE_BYTES
);
575 #ifdef CONFIG_MODULES
576 if (size
< PERCPU_ENOUGH_ROOM
)
577 size
= PERCPU_ENOUGH_ROOM
;
580 for_each_possible_cpu(i
) {
581 ptr
= alloc_bootmem_node(NODE_DATA(cpu_to_node(i
)), size
);
583 panic("Cannot allocate cpu data for CPU %d\n", i
);
585 paca
[i
].data_offset
= ptr
- __per_cpu_start
;
586 memcpy(ptr
, __per_cpu_start
, __per_cpu_end
- __per_cpu_start
);