xref: /linux/arch/powerpc/kernel/setup_32.c (revision e27ecdd94d81e5bc3d1f68591701db5adb342f0d)
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 	/* Enable early debugging if any specified (see udbg.h) */
123 	udbg_early_init();
124 
125 	/* Do some early initialization based on the flat device tree */
126 	early_init_devtree(__va(dt_ptr));
127 
128 	probe_machine();
129 
130 	setup_kdump_trampoline();
131 
132 #ifdef CONFIG_6xx
133 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
134 	    cpu_has_feature(CPU_FTR_CAN_NAP))
135 		ppc_md.power_save = ppc6xx_idle;
136 #endif
137 
138 #ifdef CONFIG_E500
139 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
140 	    cpu_has_feature(CPU_FTR_CAN_NAP))
141 		ppc_md.power_save = e500_idle;
142 #endif
143 	if (ppc_md.progress)
144 		ppc_md.progress("id mach(): done", 0x200);
145 }
146 
147 #ifdef CONFIG_BOOKE_WDT
148 /* Checks wdt=x and wdt_period=xx command-line option */
149 notrace int __init early_parse_wdt(char *p)
150 {
151 	if (p && strncmp(p, "0", 1) != 0)
152 	       booke_wdt_enabled = 1;
153 
154 	return 0;
155 }
156 early_param("wdt", early_parse_wdt);
157 
158 int __init early_parse_wdt_period (char *p)
159 {
160 	if (p)
161 		booke_wdt_period = simple_strtoul(p, NULL, 0);
162 
163 	return 0;
164 }
165 early_param("wdt_period", early_parse_wdt_period);
166 #endif	/* CONFIG_BOOKE_WDT */
167 
168 /* Checks "l2cr=xxxx" command-line option */
169 int __init ppc_setup_l2cr(char *str)
170 {
171 	if (cpu_has_feature(CPU_FTR_L2CR)) {
172 		unsigned long val = simple_strtoul(str, NULL, 0);
173 		printk(KERN_INFO "l2cr set to %lx\n", val);
174 		_set_L2CR(0);		/* force invalidate by disable cache */
175 		_set_L2CR(val);		/* and enable it */
176 	}
177 	return 1;
178 }
179 __setup("l2cr=", ppc_setup_l2cr);
180 
181 /* Checks "l3cr=xxxx" command-line option */
182 int __init ppc_setup_l3cr(char *str)
183 {
184 	if (cpu_has_feature(CPU_FTR_L3CR)) {
185 		unsigned long val = simple_strtoul(str, NULL, 0);
186 		printk(KERN_INFO "l3cr set to %lx\n", val);
187 		_set_L3CR(val);		/* and enable it */
188 	}
189 	return 1;
190 }
191 __setup("l3cr=", ppc_setup_l3cr);
192 
193 #ifdef CONFIG_GENERIC_NVRAM
194 
195 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
196 unsigned char nvram_read_byte(int addr)
197 {
198 	if (ppc_md.nvram_read_val)
199 		return ppc_md.nvram_read_val(addr);
200 	return 0xff;
201 }
202 EXPORT_SYMBOL(nvram_read_byte);
203 
204 void nvram_write_byte(unsigned char val, int addr)
205 {
206 	if (ppc_md.nvram_write_val)
207 		ppc_md.nvram_write_val(addr, val);
208 }
209 EXPORT_SYMBOL(nvram_write_byte);
210 
211 void nvram_sync(void)
212 {
213 	if (ppc_md.nvram_sync)
214 		ppc_md.nvram_sync();
215 }
216 EXPORT_SYMBOL(nvram_sync);
217 
218 #endif /* CONFIG_NVRAM */
219 
220 int __init ppc_init(void)
221 {
222 	/* clear the progress line */
223 	if (ppc_md.progress)
224 		ppc_md.progress("             ", 0xffff);
225 
226 	/* call platform init */
227 	if (ppc_md.init != NULL) {
228 		ppc_md.init();
229 	}
230 	return 0;
231 }
232 
233 arch_initcall(ppc_init);
234 
235 #ifdef CONFIG_IRQSTACKS
236 static void __init irqstack_early_init(void)
237 {
238 	unsigned int i;
239 
240 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
241 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
242 	for_each_possible_cpu(i) {
243 		softirq_ctx[i] = (struct thread_info *)
244 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
245 		hardirq_ctx[i] = (struct thread_info *)
246 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
247 	}
248 }
249 #else
250 #define irqstack_early_init()
251 #endif
252 
253 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
254 static void __init exc_lvl_early_init(void)
255 {
256 	unsigned int i;
257 
258 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
259 	 * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
260 	for_each_possible_cpu(i) {
261 		critirq_ctx[i] = (struct thread_info *)
262 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
263 #ifdef CONFIG_BOOKE
264 		dbgirq_ctx[i] = (struct thread_info *)
265 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
266 		mcheckirq_ctx[i] = (struct thread_info *)
267 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
268 #endif
269 	}
270 }
271 #else
272 #define exc_lvl_early_init()
273 #endif
274 
275 /* Warning, IO base is not yet inited */
276 void __init setup_arch(char **cmdline_p)
277 {
278 	*cmdline_p = cmd_line;
279 
280 	/* so udelay does something sensible, assume <= 1000 bogomips */
281 	loops_per_jiffy = 500000000 / HZ;
282 
283 	unflatten_device_tree();
284 	check_for_initrd();
285 
286 	if (ppc_md.init_early)
287 		ppc_md.init_early();
288 
289 	find_legacy_serial_ports();
290 
291 	smp_setup_cpu_maps();
292 
293 	/* Register early console */
294 	register_early_udbg_console();
295 
296 	xmon_setup();
297 
298 	/*
299 	 * Set cache line size based on type of cpu as a default.
300 	 * Systems with OF can look in the properties on the cpu node(s)
301 	 * for a possibly more accurate value.
302 	 */
303 	dcache_bsize = cur_cpu_spec->dcache_bsize;
304 	icache_bsize = cur_cpu_spec->icache_bsize;
305 	ucache_bsize = 0;
306 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
307 		ucache_bsize = icache_bsize = dcache_bsize;
308 
309 	/* reboot on panic */
310 	panic_timeout = 180;
311 
312 	if (ppc_md.panic)
313 		setup_panic();
314 
315 	init_mm.start_code = (unsigned long)_stext;
316 	init_mm.end_code = (unsigned long) _etext;
317 	init_mm.end_data = (unsigned long) _edata;
318 	init_mm.brk = klimit;
319 
320 	exc_lvl_early_init();
321 
322 	irqstack_early_init();
323 
324 	/* set up the bootmem stuff with available memory */
325 	do_init_bootmem();
326 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
327 
328 #ifdef CONFIG_DUMMY_CONSOLE
329 	conswitchp = &dummy_con;
330 #endif
331 
332 	if (ppc_md.setup_arch)
333 		ppc_md.setup_arch();
334 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
335 
336 #ifdef CONFIG_SWIOTLB
337 	if (ppc_swiotlb_enable)
338 		swiotlb_init();
339 #endif
340 
341 	paging_init();
342 
343 	/* Initialize the MMU context management stuff */
344 	mmu_context_init();
345 
346 }
347