xref: /openbmc/linux/arch/powerpc/kernel/setup_32.c (revision 171f1bc7)
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/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 
43 #include "setup.h"
44 
45 #define DBG(fmt...)
46 
47 extern void bootx_init(unsigned long r4, unsigned long phys);
48 
49 int boot_cpuid = -1;
50 EXPORT_SYMBOL_GPL(boot_cpuid);
51 int boot_cpuid_phys;
52 EXPORT_SYMBOL_GPL(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(u64 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 	early_init_mmu();
131 
132 	probe_machine();
133 
134 	setup_kdump_trampoline();
135 
136 #ifdef CONFIG_6xx
137 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
138 	    cpu_has_feature(CPU_FTR_CAN_NAP))
139 		ppc_md.power_save = ppc6xx_idle;
140 #endif
141 
142 #ifdef CONFIG_E500
143 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
144 	    cpu_has_feature(CPU_FTR_CAN_NAP))
145 		ppc_md.power_save = e500_idle;
146 #endif
147 	if (ppc_md.progress)
148 		ppc_md.progress("id mach(): done", 0x200);
149 }
150 
151 #ifdef CONFIG_BOOKE_WDT
152 /* Checks wdt=x and wdt_period=xx command-line option */
153 notrace int __init early_parse_wdt(char *p)
154 {
155 	if (p && strncmp(p, "0", 1) != 0)
156 	       booke_wdt_enabled = 1;
157 
158 	return 0;
159 }
160 early_param("wdt", early_parse_wdt);
161 
162 int __init early_parse_wdt_period (char *p)
163 {
164 	if (p)
165 		booke_wdt_period = simple_strtoul(p, NULL, 0);
166 
167 	return 0;
168 }
169 early_param("wdt_period", early_parse_wdt_period);
170 #endif	/* CONFIG_BOOKE_WDT */
171 
172 /* Checks "l2cr=xxxx" command-line option */
173 int __init ppc_setup_l2cr(char *str)
174 {
175 	if (cpu_has_feature(CPU_FTR_L2CR)) {
176 		unsigned long val = simple_strtoul(str, NULL, 0);
177 		printk(KERN_INFO "l2cr set to %lx\n", val);
178 		_set_L2CR(0);		/* force invalidate by disable cache */
179 		_set_L2CR(val);		/* and enable it */
180 	}
181 	return 1;
182 }
183 __setup("l2cr=", ppc_setup_l2cr);
184 
185 /* Checks "l3cr=xxxx" command-line option */
186 int __init ppc_setup_l3cr(char *str)
187 {
188 	if (cpu_has_feature(CPU_FTR_L3CR)) {
189 		unsigned long val = simple_strtoul(str, NULL, 0);
190 		printk(KERN_INFO "l3cr set to %lx\n", val);
191 		_set_L3CR(val);		/* and enable it */
192 	}
193 	return 1;
194 }
195 __setup("l3cr=", ppc_setup_l3cr);
196 
197 #ifdef CONFIG_GENERIC_NVRAM
198 
199 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
200 unsigned char nvram_read_byte(int addr)
201 {
202 	if (ppc_md.nvram_read_val)
203 		return ppc_md.nvram_read_val(addr);
204 	return 0xff;
205 }
206 EXPORT_SYMBOL(nvram_read_byte);
207 
208 void nvram_write_byte(unsigned char val, int addr)
209 {
210 	if (ppc_md.nvram_write_val)
211 		ppc_md.nvram_write_val(addr, val);
212 }
213 EXPORT_SYMBOL(nvram_write_byte);
214 
215 ssize_t nvram_get_size(void)
216 {
217 	if (ppc_md.nvram_size)
218 		return ppc_md.nvram_size();
219 	return -1;
220 }
221 EXPORT_SYMBOL(nvram_get_size);
222 
223 void nvram_sync(void)
224 {
225 	if (ppc_md.nvram_sync)
226 		ppc_md.nvram_sync();
227 }
228 EXPORT_SYMBOL(nvram_sync);
229 
230 #endif /* CONFIG_NVRAM */
231 
232 int __init ppc_init(void)
233 {
234 	/* clear the progress line */
235 	if (ppc_md.progress)
236 		ppc_md.progress("             ", 0xffff);
237 
238 	/* call platform init */
239 	if (ppc_md.init != NULL) {
240 		ppc_md.init();
241 	}
242 	return 0;
243 }
244 
245 arch_initcall(ppc_init);
246 
247 static void __init irqstack_early_init(void)
248 {
249 	unsigned int i;
250 
251 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
252 	 * as the memblock is limited to lowmem by default */
253 	for_each_possible_cpu(i) {
254 		softirq_ctx[i] = (struct thread_info *)
255 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
256 		hardirq_ctx[i] = (struct thread_info *)
257 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
258 	}
259 }
260 
261 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
262 static void __init exc_lvl_early_init(void)
263 {
264 	unsigned int i, hw_cpu;
265 
266 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
267 	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
268 	for_each_possible_cpu(i) {
269 		hw_cpu = get_hard_smp_processor_id(i);
270 		critirq_ctx[hw_cpu] = (struct thread_info *)
271 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
272 #ifdef CONFIG_BOOKE
273 		dbgirq_ctx[hw_cpu] = (struct thread_info *)
274 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
275 		mcheckirq_ctx[hw_cpu] = (struct thread_info *)
276 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
277 #endif
278 	}
279 }
280 #else
281 #define exc_lvl_early_init()
282 #endif
283 
284 /* Warning, IO base is not yet inited */
285 void __init setup_arch(char **cmdline_p)
286 {
287 	*cmdline_p = cmd_line;
288 
289 	/* so udelay does something sensible, assume <= 1000 bogomips */
290 	loops_per_jiffy = 500000000 / HZ;
291 
292 	unflatten_device_tree();
293 	check_for_initrd();
294 
295 	if (ppc_md.init_early)
296 		ppc_md.init_early();
297 
298 	find_legacy_serial_ports();
299 
300 	smp_setup_cpu_maps();
301 
302 	/* Register early console */
303 	register_early_udbg_console();
304 
305 	xmon_setup();
306 
307 	/*
308 	 * Set cache line size based on type of cpu as a default.
309 	 * Systems with OF can look in the properties on the cpu node(s)
310 	 * for a possibly more accurate value.
311 	 */
312 	dcache_bsize = cur_cpu_spec->dcache_bsize;
313 	icache_bsize = cur_cpu_spec->icache_bsize;
314 	ucache_bsize = 0;
315 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
316 		ucache_bsize = icache_bsize = dcache_bsize;
317 
318 	/* reboot on panic */
319 	panic_timeout = 180;
320 
321 	if (ppc_md.panic)
322 		setup_panic();
323 
324 	init_mm.start_code = (unsigned long)_stext;
325 	init_mm.end_code = (unsigned long) _etext;
326 	init_mm.end_data = (unsigned long) _edata;
327 	init_mm.brk = klimit;
328 
329 	exc_lvl_early_init();
330 
331 	irqstack_early_init();
332 
333 	/* set up the bootmem stuff with available memory */
334 	do_init_bootmem();
335 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
336 
337 #ifdef CONFIG_DUMMY_CONSOLE
338 	conswitchp = &dummy_con;
339 #endif
340 
341 	if (ppc_md.setup_arch)
342 		ppc_md.setup_arch();
343 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
344 
345 	paging_init();
346 
347 	/* Initialize the MMU context management stuff */
348 	mmu_context_init();
349 
350 }
351