xref: /linux/arch/powerpc/kernel/setup_32.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
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 #include <asm/mmu_context.h>
42 #include <asm/swiotlb.h>
43 
44 #include "setup.h"
45 
46 #define DBG(fmt...)
47 
48 extern void bootx_init(unsigned long r4, unsigned long phys);
49 
50 int boot_cpuid;
51 EXPORT_SYMBOL_GPL(boot_cpuid);
52 int boot_cpuid_phys;
53 
54 int smp_hw_index[NR_CPUS];
55 
56 unsigned long ISA_DMA_THRESHOLD;
57 unsigned int DMA_MODE_READ;
58 unsigned int DMA_MODE_WRITE;
59 
60 #ifdef CONFIG_VGA_CONSOLE
61 unsigned long vgacon_remap_base;
62 EXPORT_SYMBOL(vgacon_remap_base);
63 #endif
64 
65 /*
66  * These are used in binfmt_elf.c to put aux entries on the stack
67  * for each elf executable being started.
68  */
69 int dcache_bsize;
70 int icache_bsize;
71 int ucache_bsize;
72 
73 /*
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>
77  *
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
81  */
82 notrace unsigned long __init early_init(unsigned long dt_ptr)
83 {
84 	unsigned long offset = reloc_offset();
85 	struct cpu_spec *spec;
86 
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);
91 
92 	/*
93 	 * Identify the CPU type and fix up code sections
94 	 * that depend on which cpu we have.
95 	 */
96 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
97 
98 	do_feature_fixups(spec->cpu_features,
99 			  PTRRELOC(&__start___ftr_fixup),
100 			  PTRRELOC(&__stop___ftr_fixup));
101 
102 	do_feature_fixups(spec->mmu_features,
103 			  PTRRELOC(&__start___mmu_ftr_fixup),
104 			  PTRRELOC(&__stop___mmu_ftr_fixup));
105 
106 	do_lwsync_fixups(spec->cpu_features,
107 			 PTRRELOC(&__start___lwsync_fixup),
108 			 PTRRELOC(&__stop___lwsync_fixup));
109 
110 	return KERNELBASE + offset;
111 }
112 
113 
114 /*
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.
119  */
120 notrace void __init machine_init(unsigned long dt_ptr)
121 {
122 	lockdep_init();
123 
124 	/* Enable early debugging if any specified (see udbg.h) */
125 	udbg_early_init();
126 
127 	/* Do some early initialization based on the flat device tree */
128 	early_init_devtree(__va(dt_ptr));
129 
130 	probe_machine();
131 
132 	setup_kdump_trampoline();
133 
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
139 
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);
147 }
148 
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)
152 {
153 	if (p && strncmp(p, "0", 1) != 0)
154 	       booke_wdt_enabled = 1;
155 
156 	return 0;
157 }
158 early_param("wdt", early_parse_wdt);
159 
160 int __init early_parse_wdt_period (char *p)
161 {
162 	if (p)
163 		booke_wdt_period = simple_strtoul(p, NULL, 0);
164 
165 	return 0;
166 }
167 early_param("wdt_period", early_parse_wdt_period);
168 #endif	/* CONFIG_BOOKE_WDT */
169 
170 /* Checks "l2cr=xxxx" command-line option */
171 int __init ppc_setup_l2cr(char *str)
172 {
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 */
178 	}
179 	return 1;
180 }
181 __setup("l2cr=", ppc_setup_l2cr);
182 
183 /* Checks "l3cr=xxxx" command-line option */
184 int __init ppc_setup_l3cr(char *str)
185 {
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 */
190 	}
191 	return 1;
192 }
193 __setup("l3cr=", ppc_setup_l3cr);
194 
195 #ifdef CONFIG_GENERIC_NVRAM
196 
197 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
198 unsigned char nvram_read_byte(int addr)
199 {
200 	if (ppc_md.nvram_read_val)
201 		return ppc_md.nvram_read_val(addr);
202 	return 0xff;
203 }
204 EXPORT_SYMBOL(nvram_read_byte);
205 
206 void nvram_write_byte(unsigned char val, int addr)
207 {
208 	if (ppc_md.nvram_write_val)
209 		ppc_md.nvram_write_val(addr, val);
210 }
211 EXPORT_SYMBOL(nvram_write_byte);
212 
213 void nvram_sync(void)
214 {
215 	if (ppc_md.nvram_sync)
216 		ppc_md.nvram_sync();
217 }
218 EXPORT_SYMBOL(nvram_sync);
219 
220 #endif /* CONFIG_NVRAM */
221 
222 int __init ppc_init(void)
223 {
224 	/* clear the progress line */
225 	if (ppc_md.progress)
226 		ppc_md.progress("             ", 0xffff);
227 
228 	/* call platform init */
229 	if (ppc_md.init != NULL) {
230 		ppc_md.init();
231 	}
232 	return 0;
233 }
234 
235 arch_initcall(ppc_init);
236 
237 #ifdef CONFIG_IRQSTACKS
238 static void __init irqstack_early_init(void)
239 {
240 	unsigned int i;
241 
242 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
243 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
244 	for_each_possible_cpu(i) {
245 		softirq_ctx[i] = (struct thread_info *)
246 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
247 		hardirq_ctx[i] = (struct thread_info *)
248 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
249 	}
250 }
251 #else
252 #define irqstack_early_init()
253 #endif
254 
255 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
256 static void __init exc_lvl_early_init(void)
257 {
258 	unsigned int i;
259 
260 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
261 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
262 	for_each_possible_cpu(i) {
263 		critirq_ctx[i] = (struct thread_info *)
264 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
265 #ifdef CONFIG_BOOKE
266 		dbgirq_ctx[i] = (struct thread_info *)
267 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
268 		mcheckirq_ctx[i] = (struct thread_info *)
269 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
270 #endif
271 	}
272 }
273 #else
274 #define exc_lvl_early_init()
275 #endif
276 
277 /* Warning, IO base is not yet inited */
278 void __init setup_arch(char **cmdline_p)
279 {
280 	*cmdline_p = cmd_line;
281 
282 	/* so udelay does something sensible, assume <= 1000 bogomips */
283 	loops_per_jiffy = 500000000 / HZ;
284 
285 	unflatten_device_tree();
286 	check_for_initrd();
287 
288 	if (ppc_md.init_early)
289 		ppc_md.init_early();
290 
291 	find_legacy_serial_ports();
292 
293 	smp_setup_cpu_maps();
294 
295 	/* Register early console */
296 	register_early_udbg_console();
297 
298 	xmon_setup();
299 
300 	/*
301 	 * Set cache line size based on type of cpu as a default.
302 	 * Systems with OF can look in the properties on the cpu node(s)
303 	 * for a possibly more accurate value.
304 	 */
305 	dcache_bsize = cur_cpu_spec->dcache_bsize;
306 	icache_bsize = cur_cpu_spec->icache_bsize;
307 	ucache_bsize = 0;
308 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
309 		ucache_bsize = icache_bsize = dcache_bsize;
310 
311 	/* reboot on panic */
312 	panic_timeout = 180;
313 
314 	if (ppc_md.panic)
315 		setup_panic();
316 
317 	init_mm.start_code = (unsigned long)_stext;
318 	init_mm.end_code = (unsigned long) _etext;
319 	init_mm.end_data = (unsigned long) _edata;
320 	init_mm.brk = klimit;
321 
322 	exc_lvl_early_init();
323 
324 	irqstack_early_init();
325 
326 	/* set up the bootmem stuff with available memory */
327 	do_init_bootmem();
328 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
329 
330 #ifdef CONFIG_DUMMY_CONSOLE
331 	conswitchp = &dummy_con;
332 #endif
333 
334 	if (ppc_md.setup_arch)
335 		ppc_md.setup_arch();
336 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
337 
338 #ifdef CONFIG_SWIOTLB
339 	if (ppc_swiotlb_enable)
340 		swiotlb_init();
341 #endif
342 
343 	paging_init();
344 
345 	/* Initialize the MMU context management stuff */
346 	mmu_context_init();
347 
348 }
349