xref: /linux/arch/powerpc/kernel/setup_32.c (revision 9ffc93f203c18a70623f21950f1dd473c9ec48cd)
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/memblock.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/pmac_feature.h>
34 #include <asm/sections.h>
35 #include <asm/nvram.h>
36 #include <asm/xmon.h>
37 #include <asm/time.h>
38 #include <asm/serial.h>
39 #include <asm/udbg.h>
40 #include <asm/mmu_context.h>
41 
42 #include "setup.h"
43 
44 #define DBG(fmt...)
45 
46 extern void bootx_init(unsigned long r4, unsigned long phys);
47 
48 int boot_cpuid = -1;
49 EXPORT_SYMBOL_GPL(boot_cpuid);
50 int boot_cpuid_phys;
51 EXPORT_SYMBOL_GPL(boot_cpuid_phys);
52 
53 int smp_hw_index[NR_CPUS];
54 
55 unsigned long ISA_DMA_THRESHOLD;
56 unsigned int DMA_MODE_READ;
57 unsigned int DMA_MODE_WRITE;
58 
59 #ifdef CONFIG_VGA_CONSOLE
60 unsigned long vgacon_remap_base;
61 EXPORT_SYMBOL(vgacon_remap_base);
62 #endif
63 
64 /*
65  * These are used in binfmt_elf.c to put aux entries on the stack
66  * for each elf executable being started.
67  */
68 int dcache_bsize;
69 int icache_bsize;
70 int ucache_bsize;
71 
72 /*
73  * We're called here very early in the boot.  We determine the machine
74  * type and call the appropriate low-level setup functions.
75  *  -- Cort <cort@fsmlabs.com>
76  *
77  * Note that the kernel may be running at an address which is different
78  * from the address that it was linked at, so we must use RELOC/PTRRELOC
79  * to access static data (including strings).  -- paulus
80  */
81 notrace unsigned long __init early_init(unsigned long dt_ptr)
82 {
83 	unsigned long offset = reloc_offset();
84 	struct cpu_spec *spec;
85 
86 	/* First zero the BSS -- use memset_io, some platforms don't have
87 	 * caches on yet */
88 	memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
89 			__bss_stop - __bss_start);
90 
91 	/*
92 	 * Identify the CPU type and fix up code sections
93 	 * that depend on which cpu we have.
94 	 */
95 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
96 
97 	do_feature_fixups(spec->cpu_features,
98 			  PTRRELOC(&__start___ftr_fixup),
99 			  PTRRELOC(&__stop___ftr_fixup));
100 
101 	do_feature_fixups(spec->mmu_features,
102 			  PTRRELOC(&__start___mmu_ftr_fixup),
103 			  PTRRELOC(&__stop___mmu_ftr_fixup));
104 
105 	do_lwsync_fixups(spec->cpu_features,
106 			 PTRRELOC(&__start___lwsync_fixup),
107 			 PTRRELOC(&__stop___lwsync_fixup));
108 
109 	do_final_fixups();
110 
111 	return KERNELBASE + offset;
112 }
113 
114 
115 /*
116  * Find out what kind of machine we're on and save any data we need
117  * from the early boot process (devtree is copied on pmac by prom_init()).
118  * This is called very early on the boot process, after a minimal
119  * MMU environment has been set up but before MMU_init is called.
120  */
121 notrace void __init machine_init(u64 dt_ptr)
122 {
123 	lockdep_init();
124 
125 	/* Enable early debugging if any specified (see udbg.h) */
126 	udbg_early_init();
127 
128 	/* Do some early initialization based on the flat device tree */
129 	early_init_devtree(__va(dt_ptr));
130 
131 	early_init_mmu();
132 
133 	probe_machine();
134 
135 	setup_kdump_trampoline();
136 
137 #ifdef CONFIG_6xx
138 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
139 	    cpu_has_feature(CPU_FTR_CAN_NAP))
140 		ppc_md.power_save = ppc6xx_idle;
141 #endif
142 
143 #ifdef CONFIG_E500
144 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
145 	    cpu_has_feature(CPU_FTR_CAN_NAP))
146 		ppc_md.power_save = e500_idle;
147 #endif
148 	if (ppc_md.progress)
149 		ppc_md.progress("id mach(): done", 0x200);
150 }
151 
152 #ifdef CONFIG_BOOKE_WDT
153 /* Checks wdt=x and wdt_period=xx command-line option */
154 notrace int __init early_parse_wdt(char *p)
155 {
156 	if (p && strncmp(p, "0", 1) != 0)
157 	       booke_wdt_enabled = 1;
158 
159 	return 0;
160 }
161 early_param("wdt", early_parse_wdt);
162 
163 int __init early_parse_wdt_period (char *p)
164 {
165 	if (p)
166 		booke_wdt_period = simple_strtoul(p, NULL, 0);
167 
168 	return 0;
169 }
170 early_param("wdt_period", early_parse_wdt_period);
171 #endif	/* CONFIG_BOOKE_WDT */
172 
173 /* Checks "l2cr=xxxx" command-line option */
174 int __init ppc_setup_l2cr(char *str)
175 {
176 	if (cpu_has_feature(CPU_FTR_L2CR)) {
177 		unsigned long val = simple_strtoul(str, NULL, 0);
178 		printk(KERN_INFO "l2cr set to %lx\n", val);
179 		_set_L2CR(0);		/* force invalidate by disable cache */
180 		_set_L2CR(val);		/* and enable it */
181 	}
182 	return 1;
183 }
184 __setup("l2cr=", ppc_setup_l2cr);
185 
186 /* Checks "l3cr=xxxx" command-line option */
187 int __init ppc_setup_l3cr(char *str)
188 {
189 	if (cpu_has_feature(CPU_FTR_L3CR)) {
190 		unsigned long val = simple_strtoul(str, NULL, 0);
191 		printk(KERN_INFO "l3cr set to %lx\n", val);
192 		_set_L3CR(val);		/* and enable it */
193 	}
194 	return 1;
195 }
196 __setup("l3cr=", ppc_setup_l3cr);
197 
198 #ifdef CONFIG_GENERIC_NVRAM
199 
200 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
201 unsigned char nvram_read_byte(int addr)
202 {
203 	if (ppc_md.nvram_read_val)
204 		return ppc_md.nvram_read_val(addr);
205 	return 0xff;
206 }
207 EXPORT_SYMBOL(nvram_read_byte);
208 
209 void nvram_write_byte(unsigned char val, int addr)
210 {
211 	if (ppc_md.nvram_write_val)
212 		ppc_md.nvram_write_val(addr, val);
213 }
214 EXPORT_SYMBOL(nvram_write_byte);
215 
216 ssize_t nvram_get_size(void)
217 {
218 	if (ppc_md.nvram_size)
219 		return ppc_md.nvram_size();
220 	return -1;
221 }
222 EXPORT_SYMBOL(nvram_get_size);
223 
224 void nvram_sync(void)
225 {
226 	if (ppc_md.nvram_sync)
227 		ppc_md.nvram_sync();
228 }
229 EXPORT_SYMBOL(nvram_sync);
230 
231 #endif /* CONFIG_NVRAM */
232 
233 int __init ppc_init(void)
234 {
235 	/* clear the progress line */
236 	if (ppc_md.progress)
237 		ppc_md.progress("             ", 0xffff);
238 
239 	/* call platform init */
240 	if (ppc_md.init != NULL) {
241 		ppc_md.init();
242 	}
243 	return 0;
244 }
245 
246 arch_initcall(ppc_init);
247 
248 static void __init irqstack_early_init(void)
249 {
250 	unsigned int i;
251 
252 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
253 	 * as the memblock is limited to lowmem by default */
254 	for_each_possible_cpu(i) {
255 		softirq_ctx[i] = (struct thread_info *)
256 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
257 		hardirq_ctx[i] = (struct thread_info *)
258 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
259 	}
260 }
261 
262 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
263 static void __init exc_lvl_early_init(void)
264 {
265 	unsigned int i, hw_cpu;
266 
267 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
268 	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
269 	for_each_possible_cpu(i) {
270 		hw_cpu = get_hard_smp_processor_id(i);
271 		critirq_ctx[hw_cpu] = (struct thread_info *)
272 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
273 #ifdef CONFIG_BOOKE
274 		dbgirq_ctx[hw_cpu] = (struct thread_info *)
275 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
276 		mcheckirq_ctx[hw_cpu] = (struct thread_info *)
277 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
278 #endif
279 	}
280 }
281 #else
282 #define exc_lvl_early_init()
283 #endif
284 
285 /* Warning, IO base is not yet inited */
286 void __init setup_arch(char **cmdline_p)
287 {
288 	*cmdline_p = cmd_line;
289 
290 	/* so udelay does something sensible, assume <= 1000 bogomips */
291 	loops_per_jiffy = 500000000 / HZ;
292 
293 	unflatten_device_tree();
294 	check_for_initrd();
295 
296 	if (ppc_md.init_early)
297 		ppc_md.init_early();
298 
299 	find_legacy_serial_ports();
300 
301 	smp_setup_cpu_maps();
302 
303 	/* Register early console */
304 	register_early_udbg_console();
305 
306 	xmon_setup();
307 
308 	/*
309 	 * Set cache line size based on type of cpu as a default.
310 	 * Systems with OF can look in the properties on the cpu node(s)
311 	 * for a possibly more accurate value.
312 	 */
313 	dcache_bsize = cur_cpu_spec->dcache_bsize;
314 	icache_bsize = cur_cpu_spec->icache_bsize;
315 	ucache_bsize = 0;
316 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
317 		ucache_bsize = icache_bsize = dcache_bsize;
318 
319 	/* reboot on panic */
320 	panic_timeout = 180;
321 
322 	if (ppc_md.panic)
323 		setup_panic();
324 
325 	init_mm.start_code = (unsigned long)_stext;
326 	init_mm.end_code = (unsigned long) _etext;
327 	init_mm.end_data = (unsigned long) _edata;
328 	init_mm.brk = klimit;
329 
330 	exc_lvl_early_init();
331 
332 	irqstack_early_init();
333 
334 	/* set up the bootmem stuff with available memory */
335 	do_init_bootmem();
336 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
337 
338 #ifdef CONFIG_DUMMY_CONSOLE
339 	conswitchp = &dummy_con;
340 #endif
341 
342 	if (ppc_md.setup_arch)
343 		ppc_md.setup_arch();
344 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
345 
346 	paging_init();
347 
348 	/* Initialize the MMU context management stuff */
349 	mmu_context_init();
350 
351 }
352