xref: /linux/arch/powerpc/kernel/setup_32.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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/seq_file.h>
15 #include <linux/root_dev.h>
16 #include <linux/cpu.h>
17 #include <linux/console.h>
18 #include <linux/memblock.h>
19 
20 #include <asm/io.h>
21 #include <asm/prom.h>
22 #include <asm/processor.h>
23 #include <asm/pgtable.h>
24 #include <asm/setup.h>
25 #include <asm/smp.h>
26 #include <asm/elf.h>
27 #include <asm/cputable.h>
28 #include <asm/bootx.h>
29 #include <asm/btext.h>
30 #include <asm/machdep.h>
31 #include <asm/uaccess.h>
32 #include <asm/pmac_feature.h>
33 #include <asm/sections.h>
34 #include <asm/nvram.h>
35 #include <asm/xmon.h>
36 #include <asm/time.h>
37 #include <asm/serial.h>
38 #include <asm/udbg.h>
39 #include <asm/mmu_context.h>
40 #include <asm/epapr_hcalls.h>
41 
42 #define DBG(fmt...)
43 
44 extern void bootx_init(unsigned long r4, unsigned long phys);
45 
46 int boot_cpuid_phys;
47 EXPORT_SYMBOL_GPL(boot_cpuid_phys);
48 
49 int smp_hw_index[NR_CPUS];
50 
51 unsigned long ISA_DMA_THRESHOLD;
52 unsigned int DMA_MODE_READ;
53 unsigned int DMA_MODE_WRITE;
54 
55 /*
56  * These are used in binfmt_elf.c to put aux entries on the stack
57  * for each elf executable being started.
58  */
59 int dcache_bsize;
60 int icache_bsize;
61 int ucache_bsize;
62 
63 /*
64  * We're called here very early in the boot.  We determine the machine
65  * type and call the appropriate low-level setup functions.
66  *  -- Cort <cort@fsmlabs.com>
67  *
68  * Note that the kernel may be running at an address which is different
69  * from the address that it was linked at, so we must use RELOC/PTRRELOC
70  * to access static data (including strings).  -- paulus
71  */
72 notrace unsigned long __init early_init(unsigned long dt_ptr)
73 {
74 	unsigned long offset = reloc_offset();
75 	struct cpu_spec *spec;
76 
77 	/* First zero the BSS -- use memset_io, some platforms don't have
78 	 * caches on yet */
79 	memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
80 			__bss_stop - __bss_start);
81 
82 	/*
83 	 * Identify the CPU type and fix up code sections
84 	 * that depend on which cpu we have.
85 	 */
86 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
87 
88 	do_feature_fixups(spec->cpu_features,
89 			  PTRRELOC(&__start___ftr_fixup),
90 			  PTRRELOC(&__stop___ftr_fixup));
91 
92 	do_feature_fixups(spec->mmu_features,
93 			  PTRRELOC(&__start___mmu_ftr_fixup),
94 			  PTRRELOC(&__stop___mmu_ftr_fixup));
95 
96 	do_lwsync_fixups(spec->cpu_features,
97 			 PTRRELOC(&__start___lwsync_fixup),
98 			 PTRRELOC(&__stop___lwsync_fixup));
99 
100 	do_final_fixups();
101 
102 	return KERNELBASE + offset;
103 }
104 
105 
106 /*
107  * Find out what kind of machine we're on and save any data we need
108  * from the early boot process (devtree is copied on pmac by prom_init()).
109  * This is called very early on the boot process, after a minimal
110  * MMU environment has been set up but before MMU_init is called.
111  */
112 notrace void __init machine_init(u64 dt_ptr)
113 {
114 	lockdep_init();
115 
116 	/* Enable early debugging if any specified (see udbg.h) */
117 	udbg_early_init();
118 
119 	/* Do some early initialization based on the flat device tree */
120 	early_init_devtree(__va(dt_ptr));
121 
122 	epapr_paravirt_early_init();
123 
124 	early_init_mmu();
125 
126 	probe_machine();
127 
128 	setup_kdump_trampoline();
129 
130 #ifdef CONFIG_6xx
131 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
132 	    cpu_has_feature(CPU_FTR_CAN_NAP))
133 		ppc_md.power_save = ppc6xx_idle;
134 #endif
135 
136 #ifdef CONFIG_E500
137 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
138 	    cpu_has_feature(CPU_FTR_CAN_NAP))
139 		ppc_md.power_save = e500_idle;
140 #endif
141 	if (ppc_md.progress)
142 		ppc_md.progress("id mach(): done", 0x200);
143 }
144 
145 /* Checks "l2cr=xxxx" command-line option */
146 int __init ppc_setup_l2cr(char *str)
147 {
148 	if (cpu_has_feature(CPU_FTR_L2CR)) {
149 		unsigned long val = simple_strtoul(str, NULL, 0);
150 		printk(KERN_INFO "l2cr set to %lx\n", val);
151 		_set_L2CR(0);		/* force invalidate by disable cache */
152 		_set_L2CR(val);		/* and enable it */
153 	}
154 	return 1;
155 }
156 __setup("l2cr=", ppc_setup_l2cr);
157 
158 /* Checks "l3cr=xxxx" command-line option */
159 int __init ppc_setup_l3cr(char *str)
160 {
161 	if (cpu_has_feature(CPU_FTR_L3CR)) {
162 		unsigned long val = simple_strtoul(str, NULL, 0);
163 		printk(KERN_INFO "l3cr set to %lx\n", val);
164 		_set_L3CR(val);		/* and enable it */
165 	}
166 	return 1;
167 }
168 __setup("l3cr=", ppc_setup_l3cr);
169 
170 #ifdef CONFIG_GENERIC_NVRAM
171 
172 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
173 unsigned char nvram_read_byte(int addr)
174 {
175 	if (ppc_md.nvram_read_val)
176 		return ppc_md.nvram_read_val(addr);
177 	return 0xff;
178 }
179 EXPORT_SYMBOL(nvram_read_byte);
180 
181 void nvram_write_byte(unsigned char val, int addr)
182 {
183 	if (ppc_md.nvram_write_val)
184 		ppc_md.nvram_write_val(addr, val);
185 }
186 EXPORT_SYMBOL(nvram_write_byte);
187 
188 ssize_t nvram_get_size(void)
189 {
190 	if (ppc_md.nvram_size)
191 		return ppc_md.nvram_size();
192 	return -1;
193 }
194 EXPORT_SYMBOL(nvram_get_size);
195 
196 void nvram_sync(void)
197 {
198 	if (ppc_md.nvram_sync)
199 		ppc_md.nvram_sync();
200 }
201 EXPORT_SYMBOL(nvram_sync);
202 
203 #endif /* CONFIG_NVRAM */
204 
205 int __init ppc_init(void)
206 {
207 	/* clear the progress line */
208 	if (ppc_md.progress)
209 		ppc_md.progress("             ", 0xffff);
210 
211 	/* call platform init */
212 	if (ppc_md.init != NULL) {
213 		ppc_md.init();
214 	}
215 	return 0;
216 }
217 
218 arch_initcall(ppc_init);
219 
220 static void __init irqstack_early_init(void)
221 {
222 	unsigned int i;
223 
224 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
225 	 * as the memblock is limited to lowmem by default */
226 	for_each_possible_cpu(i) {
227 		softirq_ctx[i] = (struct thread_info *)
228 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
229 		hardirq_ctx[i] = (struct thread_info *)
230 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
231 	}
232 }
233 
234 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
235 static void __init exc_lvl_early_init(void)
236 {
237 	unsigned int i, hw_cpu;
238 
239 	/* interrupt stacks must be in lowmem, we get that for free on ppc32
240 	 * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
241 	for_each_possible_cpu(i) {
242 #ifdef CONFIG_SMP
243 		hw_cpu = get_hard_smp_processor_id(i);
244 #else
245 		hw_cpu = 0;
246 #endif
247 
248 		critirq_ctx[hw_cpu] = (struct thread_info *)
249 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
250 #ifdef CONFIG_BOOKE
251 		dbgirq_ctx[hw_cpu] = (struct thread_info *)
252 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
253 		mcheckirq_ctx[hw_cpu] = (struct thread_info *)
254 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
255 #endif
256 	}
257 }
258 #else
259 #define exc_lvl_early_init()
260 #endif
261 
262 /* Warning, IO base is not yet inited */
263 void __init setup_arch(char **cmdline_p)
264 {
265 	*cmdline_p = boot_command_line;
266 
267 	/* so udelay does something sensible, assume <= 1000 bogomips */
268 	loops_per_jiffy = 500000000 / HZ;
269 
270 	unflatten_device_tree();
271 	check_for_initrd();
272 
273 	if (ppc_md.init_early)
274 		ppc_md.init_early();
275 
276 	find_legacy_serial_ports();
277 
278 	smp_setup_cpu_maps();
279 
280 	/* Register early console */
281 	register_early_udbg_console();
282 
283 	xmon_setup();
284 
285 	/*
286 	 * Set cache line size based on type of cpu as a default.
287 	 * Systems with OF can look in the properties on the cpu node(s)
288 	 * for a possibly more accurate value.
289 	 */
290 	dcache_bsize = cur_cpu_spec->dcache_bsize;
291 	icache_bsize = cur_cpu_spec->icache_bsize;
292 	ucache_bsize = 0;
293 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
294 		ucache_bsize = icache_bsize = dcache_bsize;
295 
296 	if (ppc_md.panic)
297 		setup_panic();
298 
299 	init_mm.start_code = (unsigned long)_stext;
300 	init_mm.end_code = (unsigned long) _etext;
301 	init_mm.end_data = (unsigned long) _edata;
302 	init_mm.brk = klimit;
303 
304 	exc_lvl_early_init();
305 
306 	irqstack_early_init();
307 
308 	initmem_init();
309 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: initmem", 0x3eab);
310 
311 #ifdef CONFIG_DUMMY_CONSOLE
312 	conswitchp = &dummy_con;
313 #endif
314 
315 	if (ppc_md.setup_arch)
316 		ppc_md.setup_arch();
317 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
318 
319 	paging_init();
320 
321 	/* Initialize the MMU context management stuff */
322 	mmu_context_init();
323 }
324