xref: /openbmc/linux/arch/powerpc/kernel/setup_32.c (revision a1e58bbd)
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 #if defined(CONFIG_IDE) || defined(CONFIG_IDE_MODULE)
14 #include <linux/ide.h>
15 #endif
16 #include <linux/tty.h>
17 #include <linux/bootmem.h>
18 #include <linux/seq_file.h>
19 #include <linux/root_dev.h>
20 #include <linux/cpu.h>
21 #include <linux/console.h>
22 
23 #include <asm/io.h>
24 #include <asm/prom.h>
25 #include <asm/processor.h>
26 #include <asm/pgtable.h>
27 #include <asm/setup.h>
28 #include <asm/smp.h>
29 #include <asm/elf.h>
30 #include <asm/cputable.h>
31 #include <asm/bootx.h>
32 #include <asm/btext.h>
33 #include <asm/machdep.h>
34 #include <asm/uaccess.h>
35 #include <asm/system.h>
36 #include <asm/pmac_feature.h>
37 #include <asm/sections.h>
38 #include <asm/nvram.h>
39 #include <asm/xmon.h>
40 #include <asm/time.h>
41 #include <asm/serial.h>
42 #include <asm/udbg.h>
43 
44 #include "setup.h"
45 
46 #define DBG(fmt...)
47 
48 #if defined CONFIG_KGDB
49 #include <asm/kgdb.h>
50 #endif
51 
52 extern void bootx_init(unsigned long r4, unsigned long phys);
53 
54 #if defined(CONFIG_BLK_DEV_IDE) || defined(CONFIG_BLK_DEV_IDE_MODULE)
55 struct ide_machdep_calls ppc_ide_md;
56 EXPORT_SYMBOL(ppc_ide_md);
57 #endif
58 
59 int boot_cpuid;
60 EXPORT_SYMBOL_GPL(boot_cpuid);
61 int boot_cpuid_phys;
62 
63 unsigned long ISA_DMA_THRESHOLD;
64 unsigned int DMA_MODE_READ;
65 unsigned int DMA_MODE_WRITE;
66 
67 int have_of = 1;
68 
69 #ifdef CONFIG_VGA_CONSOLE
70 unsigned long vgacon_remap_base;
71 EXPORT_SYMBOL(vgacon_remap_base);
72 #endif
73 
74 /*
75  * These are used in binfmt_elf.c to put aux entries on the stack
76  * for each elf executable being started.
77  */
78 int dcache_bsize;
79 int icache_bsize;
80 int ucache_bsize;
81 
82 /*
83  * We're called here very early in the boot.  We determine the machine
84  * type and call the appropriate low-level setup functions.
85  *  -- Cort <cort@fsmlabs.com>
86  *
87  * Note that the kernel may be running at an address which is different
88  * from the address that it was linked at, so we must use RELOC/PTRRELOC
89  * to access static data (including strings).  -- paulus
90  */
91 unsigned long __init early_init(unsigned long dt_ptr)
92 {
93 	unsigned long offset = reloc_offset();
94 	struct cpu_spec *spec;
95 
96 	/* First zero the BSS -- use memset_io, some platforms don't have
97 	 * caches on yet */
98 	memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
99 			__bss_stop - __bss_start);
100 
101 	/*
102 	 * Identify the CPU type and fix up code sections
103 	 * that depend on which cpu we have.
104 	 */
105 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
106 
107 	do_feature_fixups(spec->cpu_features,
108 			  PTRRELOC(&__start___ftr_fixup),
109 			  PTRRELOC(&__stop___ftr_fixup));
110 
111 	return KERNELBASE + offset;
112 }
113 
114 
115 /*
116  * Find out what kind of machine we're on and save any data we need
117  * from the early boot process (devtree is copied on pmac by prom_init()).
118  * This is called very early on the boot process, after a minimal
119  * MMU environment has been set up but before MMU_init is called.
120  */
121 void __init machine_init(unsigned long dt_ptr, unsigned long phys)
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 #ifdef CONFIG_6xx
132 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
133 	    cpu_has_feature(CPU_FTR_CAN_NAP))
134 		ppc_md.power_save = ppc6xx_idle;
135 #endif
136 
137 	if (ppc_md.progress)
138 		ppc_md.progress("id mach(): done", 0x200);
139 }
140 
141 #ifdef CONFIG_BOOKE_WDT
142 /* Checks wdt=x and wdt_period=xx command-line option */
143 int __init early_parse_wdt(char *p)
144 {
145 	if (p && strncmp(p, "0", 1) != 0)
146 	       booke_wdt_enabled = 1;
147 
148 	return 0;
149 }
150 early_param("wdt", early_parse_wdt);
151 
152 int __init early_parse_wdt_period (char *p)
153 {
154 	if (p)
155 		booke_wdt_period = simple_strtoul(p, NULL, 0);
156 
157 	return 0;
158 }
159 early_param("wdt_period", early_parse_wdt_period);
160 #endif	/* CONFIG_BOOKE_WDT */
161 
162 /* Checks "l2cr=xxxx" command-line option */
163 int __init ppc_setup_l2cr(char *str)
164 {
165 	if (cpu_has_feature(CPU_FTR_L2CR)) {
166 		unsigned long val = simple_strtoul(str, NULL, 0);
167 		printk(KERN_INFO "l2cr set to %lx\n", val);
168 		_set_L2CR(0);		/* force invalidate by disable cache */
169 		_set_L2CR(val);		/* and enable it */
170 	}
171 	return 1;
172 }
173 __setup("l2cr=", ppc_setup_l2cr);
174 
175 #ifdef CONFIG_GENERIC_NVRAM
176 
177 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
178 unsigned char nvram_read_byte(int addr)
179 {
180 	if (ppc_md.nvram_read_val)
181 		return ppc_md.nvram_read_val(addr);
182 	return 0xff;
183 }
184 EXPORT_SYMBOL(nvram_read_byte);
185 
186 void nvram_write_byte(unsigned char val, int addr)
187 {
188 	if (ppc_md.nvram_write_val)
189 		ppc_md.nvram_write_val(addr, val);
190 }
191 EXPORT_SYMBOL(nvram_write_byte);
192 
193 void nvram_sync(void)
194 {
195 	if (ppc_md.nvram_sync)
196 		ppc_md.nvram_sync();
197 }
198 EXPORT_SYMBOL(nvram_sync);
199 
200 #endif /* CONFIG_NVRAM */
201 
202 static DEFINE_PER_CPU(struct cpu, cpu_devices);
203 
204 int __init ppc_init(void)
205 {
206 	int cpu;
207 
208 	/* clear the progress line */
209 	if (ppc_md.progress)
210 		ppc_md.progress("             ", 0xffff);
211 
212 	/* register CPU devices */
213 	for_each_possible_cpu(cpu) {
214 		struct cpu *c = &per_cpu(cpu_devices, cpu);
215 		c->hotpluggable = 1;
216 		register_cpu(c, cpu);
217 	}
218 
219 	/* call platform init */
220 	if (ppc_md.init != NULL) {
221 		ppc_md.init();
222 	}
223 	return 0;
224 }
225 
226 arch_initcall(ppc_init);
227 
228 /* Warning, IO base is not yet inited */
229 void __init setup_arch(char **cmdline_p)
230 {
231 	*cmdline_p = cmd_line;
232 
233 	/* so udelay does something sensible, assume <= 1000 bogomips */
234 	loops_per_jiffy = 500000000 / HZ;
235 
236 	unflatten_device_tree();
237 	check_for_initrd();
238 
239 	if (ppc_md.init_early)
240 		ppc_md.init_early();
241 
242 	find_legacy_serial_ports();
243 
244 	smp_setup_cpu_maps();
245 
246 	/* Register early console */
247 	register_early_udbg_console();
248 
249 	xmon_setup();
250 
251 #if defined(CONFIG_KGDB)
252 	if (ppc_md.kgdb_map_scc)
253 		ppc_md.kgdb_map_scc();
254 	set_debug_traps();
255 	if (strstr(cmd_line, "gdb")) {
256 		if (ppc_md.progress)
257 			ppc_md.progress("setup_arch: kgdb breakpoint", 0x4000);
258 		printk("kgdb breakpoint activated\n");
259 		breakpoint();
260 	}
261 #endif
262 
263 	/*
264 	 * Set cache line size based on type of cpu as a default.
265 	 * Systems with OF can look in the properties on the cpu node(s)
266 	 * for a possibly more accurate value.
267 	 */
268 	dcache_bsize = cur_cpu_spec->dcache_bsize;
269 	icache_bsize = cur_cpu_spec->icache_bsize;
270 	ucache_bsize = 0;
271 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
272 		ucache_bsize = icache_bsize = dcache_bsize;
273 
274 	/* reboot on panic */
275 	panic_timeout = 180;
276 
277 	if (ppc_md.panic)
278 		setup_panic();
279 
280 	init_mm.start_code = PAGE_OFFSET;
281 	init_mm.end_code = (unsigned long) _etext;
282 	init_mm.end_data = (unsigned long) _edata;
283 	init_mm.brk = klimit;
284 
285 	/* set up the bootmem stuff with available memory */
286 	do_init_bootmem();
287 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
288 
289 #ifdef CONFIG_DUMMY_CONSOLE
290 	conswitchp = &dummy_con;
291 #endif
292 
293 	if (ppc_md.setup_arch)
294 		ppc_md.setup_arch();
295 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
296 
297 	paging_init();
298 }
299