xref: /openbmc/linux/arch/powerpc/kernel/setup_32.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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 
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 	return KERNELBASE + offset;
110 }
111 
112 
113 /*
114  * Find out what kind of machine we're on and save any data we need
115  * from the early boot process (devtree is copied on pmac by prom_init()).
116  * This is called very early on the boot process, after a minimal
117  * MMU environment has been set up but before MMU_init is called.
118  */
119 notrace void __init machine_init(unsigned long dt_ptr)
120 {
121 	lockdep_init();
122 
123 	/* Enable early debugging if any specified (see udbg.h) */
124 	udbg_early_init();
125 
126 	/* Do some early initialization based on the flat device tree */
127 	early_init_devtree(__va(dt_ptr));
128 
129 	probe_machine();
130 
131 	setup_kdump_trampoline();
132 
133 #ifdef CONFIG_6xx
134 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
135 	    cpu_has_feature(CPU_FTR_CAN_NAP))
136 		ppc_md.power_save = ppc6xx_idle;
137 #endif
138 
139 #ifdef CONFIG_E500
140 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
141 	    cpu_has_feature(CPU_FTR_CAN_NAP))
142 		ppc_md.power_save = e500_idle;
143 #endif
144 	if (ppc_md.progress)
145 		ppc_md.progress("id mach(): done", 0x200);
146 }
147 
148 #ifdef CONFIG_BOOKE_WDT
149 /* Checks wdt=x and wdt_period=xx command-line option */
150 notrace int __init early_parse_wdt(char *p)
151 {
152 	if (p && strncmp(p, "0", 1) != 0)
153 	       booke_wdt_enabled = 1;
154 
155 	return 0;
156 }
157 early_param("wdt", early_parse_wdt);
158 
159 int __init early_parse_wdt_period (char *p)
160 {
161 	if (p)
162 		booke_wdt_period = simple_strtoul(p, NULL, 0);
163 
164 	return 0;
165 }
166 early_param("wdt_period", early_parse_wdt_period);
167 #endif	/* CONFIG_BOOKE_WDT */
168 
169 /* Checks "l2cr=xxxx" command-line option */
170 int __init ppc_setup_l2cr(char *str)
171 {
172 	if (cpu_has_feature(CPU_FTR_L2CR)) {
173 		unsigned long val = simple_strtoul(str, NULL, 0);
174 		printk(KERN_INFO "l2cr set to %lx\n", val);
175 		_set_L2CR(0);		/* force invalidate by disable cache */
176 		_set_L2CR(val);		/* and enable it */
177 	}
178 	return 1;
179 }
180 __setup("l2cr=", ppc_setup_l2cr);
181 
182 /* Checks "l3cr=xxxx" command-line option */
183 int __init ppc_setup_l3cr(char *str)
184 {
185 	if (cpu_has_feature(CPU_FTR_L3CR)) {
186 		unsigned long val = simple_strtoul(str, NULL, 0);
187 		printk(KERN_INFO "l3cr set to %lx\n", val);
188 		_set_L3CR(val);		/* and enable it */
189 	}
190 	return 1;
191 }
192 __setup("l3cr=", ppc_setup_l3cr);
193 
194 #ifdef CONFIG_GENERIC_NVRAM
195 
196 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
197 unsigned char nvram_read_byte(int addr)
198 {
199 	if (ppc_md.nvram_read_val)
200 		return ppc_md.nvram_read_val(addr);
201 	return 0xff;
202 }
203 EXPORT_SYMBOL(nvram_read_byte);
204 
205 void nvram_write_byte(unsigned char val, int addr)
206 {
207 	if (ppc_md.nvram_write_val)
208 		ppc_md.nvram_write_val(addr, val);
209 }
210 EXPORT_SYMBOL(nvram_write_byte);
211 
212 ssize_t nvram_get_size(void)
213 {
214 	if (ppc_md.nvram_size)
215 		return ppc_md.nvram_size();
216 	return -1;
217 }
218 EXPORT_SYMBOL(nvram_get_size);
219 
220 void nvram_sync(void)
221 {
222 	if (ppc_md.nvram_sync)
223 		ppc_md.nvram_sync();
224 }
225 EXPORT_SYMBOL(nvram_sync);
226 
227 #endif /* CONFIG_NVRAM */
228 
229 int __init ppc_init(void)
230 {
231 	/* clear the progress line */
232 	if (ppc_md.progress)
233 		ppc_md.progress("             ", 0xffff);
234 
235 	/* call platform init */
236 	if (ppc_md.init != NULL) {
237 		ppc_md.init();
238 	}
239 	return 0;
240 }
241 
242 arch_initcall(ppc_init);
243 
244 static void __init irqstack_early_init(void)
245 {
246 	unsigned int i;
247 
248 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
249 	 * as the memblock is limited to lowmem by default */
250 	for_each_possible_cpu(i) {
251 		softirq_ctx[i] = (struct thread_info *)
252 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
253 		hardirq_ctx[i] = (struct thread_info *)
254 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
255 	}
256 }
257 
258 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
259 static void __init exc_lvl_early_init(void)
260 {
261 	unsigned int i, hw_cpu;
262 
263 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
264 	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
265 	for_each_possible_cpu(i) {
266 		hw_cpu = get_hard_smp_processor_id(i);
267 		critirq_ctx[hw_cpu] = (struct thread_info *)
268 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
269 #ifdef CONFIG_BOOKE
270 		dbgirq_ctx[hw_cpu] = (struct thread_info *)
271 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
272 		mcheckirq_ctx[hw_cpu] = (struct thread_info *)
273 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
274 #endif
275 	}
276 }
277 #else
278 #define exc_lvl_early_init()
279 #endif
280 
281 /* Warning, IO base is not yet inited */
282 void __init setup_arch(char **cmdline_p)
283 {
284 	*cmdline_p = cmd_line;
285 
286 	/* so udelay does something sensible, assume <= 1000 bogomips */
287 	loops_per_jiffy = 500000000 / HZ;
288 
289 	unflatten_device_tree();
290 	check_for_initrd();
291 
292 	if (ppc_md.init_early)
293 		ppc_md.init_early();
294 
295 	find_legacy_serial_ports();
296 
297 	smp_setup_cpu_maps();
298 
299 	/* Register early console */
300 	register_early_udbg_console();
301 
302 	xmon_setup();
303 
304 	/*
305 	 * Set cache line size based on type of cpu as a default.
306 	 * Systems with OF can look in the properties on the cpu node(s)
307 	 * for a possibly more accurate value.
308 	 */
309 	dcache_bsize = cur_cpu_spec->dcache_bsize;
310 	icache_bsize = cur_cpu_spec->icache_bsize;
311 	ucache_bsize = 0;
312 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
313 		ucache_bsize = icache_bsize = dcache_bsize;
314 
315 	/* reboot on panic */
316 	panic_timeout = 180;
317 
318 	if (ppc_md.panic)
319 		setup_panic();
320 
321 	init_mm.start_code = (unsigned long)_stext;
322 	init_mm.end_code = (unsigned long) _etext;
323 	init_mm.end_data = (unsigned long) _edata;
324 	init_mm.brk = klimit;
325 
326 	exc_lvl_early_init();
327 
328 	irqstack_early_init();
329 
330 	/* set up the bootmem stuff with available memory */
331 	do_init_bootmem();
332 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
333 
334 #ifdef CONFIG_DUMMY_CONSOLE
335 	conswitchp = &dummy_con;
336 #endif
337 
338 	if (ppc_md.setup_arch)
339 		ppc_md.setup_arch();
340 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
341 
342 	paging_init();
343 
344 	/* Initialize the MMU context management stuff */
345 	mmu_context_init();
346 
347 }
348