xref: /linux/arch/powerpc/kernel/setup_32.c (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
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 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 	return KERNELBASE + offset;
105 }
106 
107 
108 /*
109  * Find out what kind of machine we're on and save any data we need
110  * from the early boot process (devtree is copied on pmac by prom_init()).
111  * This is called very early on the boot process, after a minimal
112  * MMU environment has been set up but before MMU_init is called.
113  */
114 void __init machine_init(unsigned long dt_ptr, unsigned long phys)
115 {
116 	/* Enable early debugging if any specified (see udbg.h) */
117 	udbg_early_init();
118 
119 	/* Do some early initialization based on the flat device tree */
120 	early_init_devtree(__va(dt_ptr));
121 
122 	probe_machine();
123 
124 #ifdef CONFIG_6xx
125 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
126 	    cpu_has_feature(CPU_FTR_CAN_NAP))
127 		ppc_md.power_save = ppc6xx_idle;
128 #endif
129 
130 	if (ppc_md.progress)
131 		ppc_md.progress("id mach(): done", 0x200);
132 }
133 
134 #ifdef CONFIG_BOOKE_WDT
135 /* Checks wdt=x and wdt_period=xx command-line option */
136 int __init early_parse_wdt(char *p)
137 {
138 	if (p && strncmp(p, "0", 1) != 0)
139 	       booke_wdt_enabled = 1;
140 
141 	return 0;
142 }
143 early_param("wdt", early_parse_wdt);
144 
145 int __init early_parse_wdt_period (char *p)
146 {
147 	if (p)
148 		booke_wdt_period = simple_strtoul(p, NULL, 0);
149 
150 	return 0;
151 }
152 early_param("wdt_period", early_parse_wdt_period);
153 #endif	/* CONFIG_BOOKE_WDT */
154 
155 /* Checks "l2cr=xxxx" command-line option */
156 int __init ppc_setup_l2cr(char *str)
157 {
158 	if (cpu_has_feature(CPU_FTR_L2CR)) {
159 		unsigned long val = simple_strtoul(str, NULL, 0);
160 		printk(KERN_INFO "l2cr set to %lx\n", val);
161 		_set_L2CR(0);		/* force invalidate by disable cache */
162 		_set_L2CR(val);		/* and enable it */
163 	}
164 	return 1;
165 }
166 __setup("l2cr=", ppc_setup_l2cr);
167 
168 /* Checks "l3cr=xxxx" command-line option */
169 int __init ppc_setup_l3cr(char *str)
170 {
171 	if (cpu_has_feature(CPU_FTR_L3CR)) {
172 		unsigned long val = simple_strtoul(str, NULL, 0);
173 		printk(KERN_INFO "l3cr set to %lx\n", val);
174 		_set_L3CR(val);		/* and enable it */
175 	}
176 	return 1;
177 }
178 __setup("l3cr=", ppc_setup_l3cr);
179 
180 #ifdef CONFIG_GENERIC_NVRAM
181 
182 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
183 unsigned char nvram_read_byte(int addr)
184 {
185 	if (ppc_md.nvram_read_val)
186 		return ppc_md.nvram_read_val(addr);
187 	return 0xff;
188 }
189 EXPORT_SYMBOL(nvram_read_byte);
190 
191 void nvram_write_byte(unsigned char val, int addr)
192 {
193 	if (ppc_md.nvram_write_val)
194 		ppc_md.nvram_write_val(addr, val);
195 }
196 EXPORT_SYMBOL(nvram_write_byte);
197 
198 void nvram_sync(void)
199 {
200 	if (ppc_md.nvram_sync)
201 		ppc_md.nvram_sync();
202 }
203 EXPORT_SYMBOL(nvram_sync);
204 
205 #endif /* CONFIG_NVRAM */
206 
207 static DEFINE_PER_CPU(struct cpu, cpu_devices);
208 
209 int __init ppc_init(void)
210 {
211 	int cpu;
212 
213 	/* clear the progress line */
214 	if (ppc_md.progress)
215 		ppc_md.progress("             ", 0xffff);
216 
217 	/* register CPU devices */
218 	for_each_possible_cpu(cpu) {
219 		struct cpu *c = &per_cpu(cpu_devices, cpu);
220 		c->hotpluggable = 1;
221 		register_cpu(c, cpu);
222 	}
223 
224 	/* call platform init */
225 	if (ppc_md.init != NULL) {
226 		ppc_md.init();
227 	}
228 	return 0;
229 }
230 
231 arch_initcall(ppc_init);
232 
233 #ifdef CONFIG_IRQSTACKS
234 static void __init irqstack_early_init(void)
235 {
236 	unsigned int i;
237 
238 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
239 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
240 	for_each_possible_cpu(i) {
241 		softirq_ctx[i] = (struct thread_info *)
242 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
243 		hardirq_ctx[i] = (struct thread_info *)
244 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
245 	}
246 }
247 #else
248 #define irqstack_early_init()
249 #endif
250 
251 /* Warning, IO base is not yet inited */
252 void __init setup_arch(char **cmdline_p)
253 {
254 	*cmdline_p = cmd_line;
255 
256 	/* so udelay does something sensible, assume <= 1000 bogomips */
257 	loops_per_jiffy = 500000000 / HZ;
258 
259 	unflatten_device_tree();
260 	check_for_initrd();
261 
262 	if (ppc_md.init_early)
263 		ppc_md.init_early();
264 
265 	find_legacy_serial_ports();
266 
267 	smp_setup_cpu_maps();
268 
269 	/* Register early console */
270 	register_early_udbg_console();
271 
272 	xmon_setup();
273 
274 #if defined(CONFIG_KGDB)
275 	if (ppc_md.kgdb_map_scc)
276 		ppc_md.kgdb_map_scc();
277 	set_debug_traps();
278 	if (strstr(cmd_line, "gdb")) {
279 		if (ppc_md.progress)
280 			ppc_md.progress("setup_arch: kgdb breakpoint", 0x4000);
281 		printk("kgdb breakpoint activated\n");
282 		breakpoint();
283 	}
284 #endif
285 
286 	/*
287 	 * Set cache line size based on type of cpu as a default.
288 	 * Systems with OF can look in the properties on the cpu node(s)
289 	 * for a possibly more accurate value.
290 	 */
291 	dcache_bsize = cur_cpu_spec->dcache_bsize;
292 	icache_bsize = cur_cpu_spec->icache_bsize;
293 	ucache_bsize = 0;
294 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
295 		ucache_bsize = icache_bsize = dcache_bsize;
296 
297 	/* reboot on panic */
298 	panic_timeout = 180;
299 
300 	if (ppc_md.panic)
301 		setup_panic();
302 
303 	init_mm.start_code = (unsigned long)_stext;
304 	init_mm.end_code = (unsigned long) _etext;
305 	init_mm.end_data = (unsigned long) _edata;
306 	init_mm.brk = klimit;
307 
308 	irqstack_early_init();
309 
310 	/* set up the bootmem stuff with available memory */
311 	do_init_bootmem();
312 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
313 
314 #ifdef CONFIG_DUMMY_CONSOLE
315 	conswitchp = &dummy_con;
316 #endif
317 
318 	if (ppc_md.setup_arch)
319 		ppc_md.setup_arch();
320 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
321 
322 	paging_init();
323 }
324