powerpc: Properly handshake CPUs going out of boot spin loop
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / powerpc / kernel / setup_32.c
blob620d792b52e471cbd6658dba347f10e95660bf36
1 /*
2 * Common prep/pmac/chrp boot and setup code.
3 */
5 #include <linux/module.h>
6 #include <linux/string.h>
7 #include <linux/sched.h>
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/reboot.h>
11 #include <linux/delay.h>
12 #include <linux/initrd.h>
13 #include <linux/tty.h>
14 #include <linux/bootmem.h>
15 #include <linux/seq_file.h>
16 #include <linux/root_dev.h>
17 #include <linux/cpu.h>
18 #include <linux/console.h>
19 #include <linux/memblock.h>
21 #include <asm/io.h>
22 #include <asm/prom.h>
23 #include <asm/processor.h>
24 #include <asm/pgtable.h>
25 #include <asm/setup.h>
26 #include <asm/smp.h>
27 #include <asm/elf.h>
28 #include <asm/cputable.h>
29 #include <asm/bootx.h>
30 #include <asm/btext.h>
31 #include <asm/machdep.h>
32 #include <asm/uaccess.h>
33 #include <asm/system.h>
34 #include <asm/pmac_feature.h>
35 #include <asm/sections.h>
36 #include <asm/nvram.h>
37 #include <asm/xmon.h>
38 #include <asm/time.h>
39 #include <asm/serial.h>
40 #include <asm/udbg.h>
41 #include <asm/mmu_context.h>
43 #include "setup.h"
45 #define DBG(fmt...)
47 extern void bootx_init(unsigned long r4, unsigned long phys);
49 int boot_cpuid = -1;
50 EXPORT_SYMBOL_GPL(boot_cpuid);
51 int __initdata boot_cpu_count;
52 int boot_cpuid_phys;
54 int smp_hw_index[NR_CPUS];
56 unsigned long ISA_DMA_THRESHOLD;
57 unsigned int DMA_MODE_READ;
58 unsigned int DMA_MODE_WRITE;
60 #ifdef CONFIG_VGA_CONSOLE
61 unsigned long vgacon_remap_base;
62 EXPORT_SYMBOL(vgacon_remap_base);
63 #endif
66 * These are used in binfmt_elf.c to put aux entries on the stack
67 * for each elf executable being started.
69 int dcache_bsize;
70 int icache_bsize;
71 int ucache_bsize;
74 * We're called here very early in the boot. We determine the machine
75 * type and call the appropriate low-level setup functions.
76 * -- Cort <cort@fsmlabs.com>
78 * Note that the kernel may be running at an address which is different
79 * from the address that it was linked at, so we must use RELOC/PTRRELOC
80 * to access static data (including strings). -- paulus
82 notrace unsigned long __init early_init(unsigned long dt_ptr)
84 unsigned long offset = reloc_offset();
85 struct cpu_spec *spec;
87 /* First zero the BSS -- use memset_io, some platforms don't have
88 * caches on yet */
89 memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
90 __bss_stop - __bss_start);
93 * Identify the CPU type and fix up code sections
94 * that depend on which cpu we have.
96 spec = identify_cpu(offset, mfspr(SPRN_PVR));
98 do_feature_fixups(spec->cpu_features,
99 PTRRELOC(&__start___ftr_fixup),
100 PTRRELOC(&__stop___ftr_fixup));
102 do_feature_fixups(spec->mmu_features,
103 PTRRELOC(&__start___mmu_ftr_fixup),
104 PTRRELOC(&__stop___mmu_ftr_fixup));
106 do_lwsync_fixups(spec->cpu_features,
107 PTRRELOC(&__start___lwsync_fixup),
108 PTRRELOC(&__stop___lwsync_fixup));
110 return KERNELBASE + offset;
115 * Find out what kind of machine we're on and save any data we need
116 * from the early boot process (devtree is copied on pmac by prom_init()).
117 * This is called very early on the boot process, after a minimal
118 * MMU environment has been set up but before MMU_init is called.
120 notrace void __init machine_init(unsigned long dt_ptr)
122 lockdep_init();
124 /* Enable early debugging if any specified (see udbg.h) */
125 udbg_early_init();
127 /* Do some early initialization based on the flat device tree */
128 early_init_devtree(__va(dt_ptr));
130 probe_machine();
132 setup_kdump_trampoline();
134 #ifdef CONFIG_6xx
135 if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
136 cpu_has_feature(CPU_FTR_CAN_NAP))
137 ppc_md.power_save = ppc6xx_idle;
138 #endif
140 #ifdef CONFIG_E500
141 if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
142 cpu_has_feature(CPU_FTR_CAN_NAP))
143 ppc_md.power_save = e500_idle;
144 #endif
145 if (ppc_md.progress)
146 ppc_md.progress("id mach(): done", 0x200);
149 #ifdef CONFIG_BOOKE_WDT
150 /* Checks wdt=x and wdt_period=xx command-line option */
151 notrace int __init early_parse_wdt(char *p)
153 if (p && strncmp(p, "0", 1) != 0)
154 booke_wdt_enabled = 1;
156 return 0;
158 early_param("wdt", early_parse_wdt);
160 int __init early_parse_wdt_period (char *p)
162 if (p)
163 booke_wdt_period = simple_strtoul(p, NULL, 0);
165 return 0;
167 early_param("wdt_period", early_parse_wdt_period);
168 #endif /* CONFIG_BOOKE_WDT */
170 /* Checks "l2cr=xxxx" command-line option */
171 int __init ppc_setup_l2cr(char *str)
173 if (cpu_has_feature(CPU_FTR_L2CR)) {
174 unsigned long val = simple_strtoul(str, NULL, 0);
175 printk(KERN_INFO "l2cr set to %lx\n", val);
176 _set_L2CR(0); /* force invalidate by disable cache */
177 _set_L2CR(val); /* and enable it */
179 return 1;
181 __setup("l2cr=", ppc_setup_l2cr);
183 /* Checks "l3cr=xxxx" command-line option */
184 int __init ppc_setup_l3cr(char *str)
186 if (cpu_has_feature(CPU_FTR_L3CR)) {
187 unsigned long val = simple_strtoul(str, NULL, 0);
188 printk(KERN_INFO "l3cr set to %lx\n", val);
189 _set_L3CR(val); /* and enable it */
191 return 1;
193 __setup("l3cr=", ppc_setup_l3cr);
195 #ifdef CONFIG_GENERIC_NVRAM
197 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
198 unsigned char nvram_read_byte(int addr)
200 if (ppc_md.nvram_read_val)
201 return ppc_md.nvram_read_val(addr);
202 return 0xff;
204 EXPORT_SYMBOL(nvram_read_byte);
206 void nvram_write_byte(unsigned char val, int addr)
208 if (ppc_md.nvram_write_val)
209 ppc_md.nvram_write_val(addr, val);
211 EXPORT_SYMBOL(nvram_write_byte);
213 ssize_t nvram_get_size(void)
215 if (ppc_md.nvram_size)
216 return ppc_md.nvram_size();
217 return -1;
219 EXPORT_SYMBOL(nvram_get_size);
221 void nvram_sync(void)
223 if (ppc_md.nvram_sync)
224 ppc_md.nvram_sync();
226 EXPORT_SYMBOL(nvram_sync);
228 #endif /* CONFIG_NVRAM */
230 int __init ppc_init(void)
232 /* clear the progress line */
233 if (ppc_md.progress)
234 ppc_md.progress(" ", 0xffff);
236 /* call platform init */
237 if (ppc_md.init != NULL) {
238 ppc_md.init();
240 return 0;
243 arch_initcall(ppc_init);
245 static void __init irqstack_early_init(void)
247 unsigned int i;
249 /* interrupt stacks must be in lowmem, we get that for free on ppc32
250 * as the memblock is limited to lowmem by default */
251 for_each_possible_cpu(i) {
252 softirq_ctx[i] = (struct thread_info *)
253 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
254 hardirq_ctx[i] = (struct thread_info *)
255 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
259 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
260 static void __init exc_lvl_early_init(void)
262 unsigned int i, hw_cpu;
264 /* interrupt stacks must be in lowmem, we get that for free on ppc32
265 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
266 for_each_possible_cpu(i) {
267 hw_cpu = get_hard_smp_processor_id(i);
268 critirq_ctx[hw_cpu] = (struct thread_info *)
269 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
270 #ifdef CONFIG_BOOKE
271 dbgirq_ctx[hw_cpu] = (struct thread_info *)
272 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
273 mcheckirq_ctx[hw_cpu] = (struct thread_info *)
274 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
275 #endif
278 #else
279 #define exc_lvl_early_init()
280 #endif
282 /* Warning, IO base is not yet inited */
283 void __init setup_arch(char **cmdline_p)
285 *cmdline_p = cmd_line;
287 /* so udelay does something sensible, assume <= 1000 bogomips */
288 loops_per_jiffy = 500000000 / HZ;
290 unflatten_device_tree();
291 check_for_initrd();
293 if (ppc_md.init_early)
294 ppc_md.init_early();
296 find_legacy_serial_ports();
298 smp_setup_cpu_maps();
300 /* Register early console */
301 register_early_udbg_console();
303 xmon_setup();
306 * Set cache line size based on type of cpu as a default.
307 * Systems with OF can look in the properties on the cpu node(s)
308 * for a possibly more accurate value.
310 dcache_bsize = cur_cpu_spec->dcache_bsize;
311 icache_bsize = cur_cpu_spec->icache_bsize;
312 ucache_bsize = 0;
313 if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
314 ucache_bsize = icache_bsize = dcache_bsize;
316 /* reboot on panic */
317 panic_timeout = 180;
319 if (ppc_md.panic)
320 setup_panic();
322 init_mm.start_code = (unsigned long)_stext;
323 init_mm.end_code = (unsigned long) _etext;
324 init_mm.end_data = (unsigned long) _edata;
325 init_mm.brk = klimit;
327 exc_lvl_early_init();
329 irqstack_early_init();
331 /* set up the bootmem stuff with available memory */
332 do_init_bootmem();
333 if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
335 #ifdef CONFIG_DUMMY_CONSOLE
336 conswitchp = &dummy_con;
337 #endif
339 if (ppc_md.setup_arch)
340 ppc_md.setup_arch();
341 if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
343 paging_init();
345 /* Initialize the MMU context management stuff */
346 mmu_context_init();