xref: /linux/arch/powerpc/kernel/setup_32.c (revision 185000fc556372b7fb7f26516c325f212030dbd3)
1 /*
2  * Common prep/pmac/chrp boot and setup code.
3  */
4 
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/lmb.h>
20 
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 
42 #include "setup.h"
43 
44 #define DBG(fmt...)
45 
46 #if defined CONFIG_KGDB
47 #include <asm/kgdb.h>
48 #endif
49 
50 extern void bootx_init(unsigned long r4, unsigned long phys);
51 
52 int boot_cpuid;
53 EXPORT_SYMBOL_GPL(boot_cpuid);
54 int boot_cpuid_phys;
55 
56 unsigned long ISA_DMA_THRESHOLD;
57 unsigned int DMA_MODE_READ;
58 unsigned int DMA_MODE_WRITE;
59 
60 int have_of = 1;
61 
62 #ifdef CONFIG_VGA_CONSOLE
63 unsigned long vgacon_remap_base;
64 EXPORT_SYMBOL(vgacon_remap_base);
65 #endif
66 
67 /*
68  * These are used in binfmt_elf.c to put aux entries on the stack
69  * for each elf executable being started.
70  */
71 int dcache_bsize;
72 int icache_bsize;
73 int ucache_bsize;
74 
75 /*
76  * We're called here very early in the boot.  We determine the machine
77  * type and call the appropriate low-level setup functions.
78  *  -- Cort <cort@fsmlabs.com>
79  *
80  * Note that the kernel may be running at an address which is different
81  * from the address that it was linked at, so we must use RELOC/PTRRELOC
82  * to access static data (including strings).  -- paulus
83  */
84 notrace unsigned long __init early_init(unsigned long dt_ptr)
85 {
86 	unsigned long offset = reloc_offset();
87 	struct cpu_spec *spec;
88 
89 	/* First zero the BSS -- use memset_io, some platforms don't have
90 	 * caches on yet */
91 	memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
92 			__bss_stop - __bss_start);
93 
94 	/*
95 	 * Identify the CPU type and fix up code sections
96 	 * that depend on which cpu we have.
97 	 */
98 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
99 
100 	do_feature_fixups(spec->cpu_features,
101 			  PTRRELOC(&__start___ftr_fixup),
102 			  PTRRELOC(&__stop___ftr_fixup));
103 
104 	do_lwsync_fixups(spec->cpu_features,
105 			 PTRRELOC(&__start___lwsync_fixup),
106 			 PTRRELOC(&__stop___lwsync_fixup));
107 
108 	return KERNELBASE + offset;
109 }
110 
111 
112 /*
113  * Find out what kind of machine we're on and save any data we need
114  * from the early boot process (devtree is copied on pmac by prom_init()).
115  * This is called very early on the boot process, after a minimal
116  * MMU environment has been set up but before MMU_init is called.
117  */
118 notrace void __init machine_init(unsigned long dt_ptr, unsigned long phys)
119 {
120 	/* Enable early debugging if any specified (see udbg.h) */
121 	udbg_early_init();
122 
123 	/* Do some early initialization based on the flat device tree */
124 	early_init_devtree(__va(dt_ptr));
125 
126 	probe_machine();
127 
128 #ifdef CONFIG_6xx
129 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
130 	    cpu_has_feature(CPU_FTR_CAN_NAP))
131 		ppc_md.power_save = ppc6xx_idle;
132 #endif
133 
134 #ifdef CONFIG_E500
135 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
136 	    cpu_has_feature(CPU_FTR_CAN_NAP))
137 		ppc_md.power_save = e500_idle;
138 #endif
139 	if (ppc_md.progress)
140 		ppc_md.progress("id mach(): done", 0x200);
141 }
142 
143 #ifdef CONFIG_BOOKE_WDT
144 /* Checks wdt=x and wdt_period=xx command-line option */
145 notrace int __init early_parse_wdt(char *p)
146 {
147 	if (p && strncmp(p, "0", 1) != 0)
148 	       booke_wdt_enabled = 1;
149 
150 	return 0;
151 }
152 early_param("wdt", early_parse_wdt);
153 
154 int __init early_parse_wdt_period (char *p)
155 {
156 	if (p)
157 		booke_wdt_period = simple_strtoul(p, NULL, 0);
158 
159 	return 0;
160 }
161 early_param("wdt_period", early_parse_wdt_period);
162 #endif	/* CONFIG_BOOKE_WDT */
163 
164 /* Checks "l2cr=xxxx" command-line option */
165 int __init ppc_setup_l2cr(char *str)
166 {
167 	if (cpu_has_feature(CPU_FTR_L2CR)) {
168 		unsigned long val = simple_strtoul(str, NULL, 0);
169 		printk(KERN_INFO "l2cr set to %lx\n", val);
170 		_set_L2CR(0);		/* force invalidate by disable cache */
171 		_set_L2CR(val);		/* and enable it */
172 	}
173 	return 1;
174 }
175 __setup("l2cr=", ppc_setup_l2cr);
176 
177 /* Checks "l3cr=xxxx" command-line option */
178 int __init ppc_setup_l3cr(char *str)
179 {
180 	if (cpu_has_feature(CPU_FTR_L3CR)) {
181 		unsigned long val = simple_strtoul(str, NULL, 0);
182 		printk(KERN_INFO "l3cr set to %lx\n", val);
183 		_set_L3CR(val);		/* and enable it */
184 	}
185 	return 1;
186 }
187 __setup("l3cr=", ppc_setup_l3cr);
188 
189 #ifdef CONFIG_GENERIC_NVRAM
190 
191 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
192 unsigned char nvram_read_byte(int addr)
193 {
194 	if (ppc_md.nvram_read_val)
195 		return ppc_md.nvram_read_val(addr);
196 	return 0xff;
197 }
198 EXPORT_SYMBOL(nvram_read_byte);
199 
200 void nvram_write_byte(unsigned char val, int addr)
201 {
202 	if (ppc_md.nvram_write_val)
203 		ppc_md.nvram_write_val(addr, val);
204 }
205 EXPORT_SYMBOL(nvram_write_byte);
206 
207 void nvram_sync(void)
208 {
209 	if (ppc_md.nvram_sync)
210 		ppc_md.nvram_sync();
211 }
212 EXPORT_SYMBOL(nvram_sync);
213 
214 #endif /* CONFIG_NVRAM */
215 
216 static DEFINE_PER_CPU(struct cpu, cpu_devices);
217 
218 int __init ppc_init(void)
219 {
220 	int cpu;
221 
222 	/* clear the progress line */
223 	if (ppc_md.progress)
224 		ppc_md.progress("             ", 0xffff);
225 
226 	/* register CPU devices */
227 	for_each_possible_cpu(cpu) {
228 		struct cpu *c = &per_cpu(cpu_devices, cpu);
229 		c->hotpluggable = 1;
230 		register_cpu(c, cpu);
231 	}
232 
233 	/* call platform init */
234 	if (ppc_md.init != NULL) {
235 		ppc_md.init();
236 	}
237 	return 0;
238 }
239 
240 arch_initcall(ppc_init);
241 
242 #ifdef CONFIG_IRQSTACKS
243 static void __init irqstack_early_init(void)
244 {
245 	unsigned int i;
246 
247 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
248 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
249 	for_each_possible_cpu(i) {
250 		softirq_ctx[i] = (struct thread_info *)
251 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
252 		hardirq_ctx[i] = (struct thread_info *)
253 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
254 	}
255 }
256 #else
257 #define irqstack_early_init()
258 #endif
259 
260 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
261 static void __init exc_lvl_early_init(void)
262 {
263 	unsigned int i;
264 
265 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
266 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
267 	for_each_possible_cpu(i) {
268 		critirq_ctx[i] = (struct thread_info *)
269 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
270 #ifdef CONFIG_BOOKE
271 		dbgirq_ctx[i] = (struct thread_info *)
272 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
273 		mcheckirq_ctx[i] = (struct thread_info *)
274 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
275 #endif
276 	}
277 }
278 #else
279 #define exc_lvl_early_init()
280 #endif
281 
282 /* Warning, IO base is not yet inited */
283 void __init setup_arch(char **cmdline_p)
284 {
285 	*cmdline_p = cmd_line;
286 
287 	/* so udelay does something sensible, assume <= 1000 bogomips */
288 	loops_per_jiffy = 500000000 / HZ;
289 
290 	unflatten_device_tree();
291 	check_for_initrd();
292 
293 	if (ppc_md.init_early)
294 		ppc_md.init_early();
295 
296 	find_legacy_serial_ports();
297 
298 	smp_setup_cpu_maps();
299 
300 	/* Register early console */
301 	register_early_udbg_console();
302 
303 	xmon_setup();
304 
305 #if defined(CONFIG_KGDB)
306 	if (ppc_md.kgdb_map_scc)
307 		ppc_md.kgdb_map_scc();
308 	set_debug_traps();
309 	if (strstr(cmd_line, "gdb")) {
310 		if (ppc_md.progress)
311 			ppc_md.progress("setup_arch: kgdb breakpoint", 0x4000);
312 		printk("kgdb breakpoint activated\n");
313 		breakpoint();
314 	}
315 #endif
316 
317 	/*
318 	 * Set cache line size based on type of cpu as a default.
319 	 * Systems with OF can look in the properties on the cpu node(s)
320 	 * for a possibly more accurate value.
321 	 */
322 	dcache_bsize = cur_cpu_spec->dcache_bsize;
323 	icache_bsize = cur_cpu_spec->icache_bsize;
324 	ucache_bsize = 0;
325 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
326 		ucache_bsize = icache_bsize = dcache_bsize;
327 
328 	/* reboot on panic */
329 	panic_timeout = 180;
330 
331 	if (ppc_md.panic)
332 		setup_panic();
333 
334 	init_mm.start_code = (unsigned long)_stext;
335 	init_mm.end_code = (unsigned long) _etext;
336 	init_mm.end_data = (unsigned long) _edata;
337 	init_mm.brk = klimit;
338 
339 	exc_lvl_early_init();
340 
341 	irqstack_early_init();
342 
343 	/* set up the bootmem stuff with available memory */
344 	do_init_bootmem();
345 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
346 
347 #ifdef CONFIG_DUMMY_CONSOLE
348 	conswitchp = &dummy_con;
349 #endif
350 
351 	if (ppc_md.setup_arch)
352 		ppc_md.setup_arch();
353 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
354 
355 	paging_init();
356 }
357