xref: /linux/arch/powerpc/kernel/setup_32.c (revision 606d099cdd1080bbb50ea50dc52d98252f8f10a1)
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/ide.h>
14 #include <linux/tty.h>
15 #include <linux/bootmem.h>
16 #include <linux/seq_file.h>
17 #include <linux/root_dev.h>
18 #include <linux/cpu.h>
19 #include <linux/console.h>
20 
21 #include <asm/residual.h>
22 #include <asm/io.h>
23 #include <asm/prom.h>
24 #include <asm/processor.h>
25 #include <asm/pgtable.h>
26 #include <asm/setup.h>
27 #include <asm/amigappc.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 struct ide_machdep_calls ppc_ide_md;
55 
56 int boot_cpuid;
57 EXPORT_SYMBOL_GPL(boot_cpuid);
58 int boot_cpuid_phys;
59 
60 unsigned long ISA_DMA_THRESHOLD;
61 unsigned int DMA_MODE_READ;
62 unsigned int DMA_MODE_WRITE;
63 
64 int have_of = 1;
65 
66 #ifdef CONFIG_VGA_CONSOLE
67 unsigned long vgacon_remap_base;
68 #endif
69 
70 /*
71  * These are used in binfmt_elf.c to put aux entries on the stack
72  * for each elf executable being started.
73  */
74 int dcache_bsize;
75 int icache_bsize;
76 int ucache_bsize;
77 
78 /*
79  * We're called here very early in the boot.  We determine the machine
80  * type and call the appropriate low-level setup functions.
81  *  -- Cort <cort@fsmlabs.com>
82  *
83  * Note that the kernel may be running at an address which is different
84  * from the address that it was linked at, so we must use RELOC/PTRRELOC
85  * to access static data (including strings).  -- paulus
86  */
87 unsigned long __init early_init(unsigned long dt_ptr)
88 {
89 	unsigned long offset = reloc_offset();
90 	struct cpu_spec *spec;
91 
92 	/* First zero the BSS -- use memset_io, some platforms don't have
93 	 * caches on yet */
94 	memset_io((void __iomem *)PTRRELOC(&__bss_start), 0, _end - __bss_start);
95 
96 	/*
97 	 * Identify the CPU type and fix up code sections
98 	 * that depend on which cpu we have.
99 	 */
100 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
101 
102 	do_feature_fixups(spec->cpu_features,
103 			  PTRRELOC(&__start___ftr_fixup),
104 			  PTRRELOC(&__stop___ftr_fixup));
105 
106 	return KERNELBASE + offset;
107 }
108 
109 
110 /*
111  * Find out what kind of machine we're on and save any data we need
112  * from the early boot process (devtree is copied on pmac by prom_init()).
113  * This is called very early on the boot process, after a minimal
114  * MMU environment has been set up but before MMU_init is called.
115  */
116 void __init machine_init(unsigned long dt_ptr, unsigned long phys)
117 {
118 	/* If btext is enabled, we might have a BAT setup for early display,
119 	 * thus we do enable some very basic udbg output
120 	 */
121 #ifdef CONFIG_BOOTX_TEXT
122 	udbg_putc = btext_drawchar;
123 #endif
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 #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 	if (ppc_md.progress)
137 		ppc_md.progress("id mach(): done", 0x200);
138 }
139 
140 #ifdef CONFIG_BOOKE_WDT
141 /* Checks wdt=x and wdt_period=xx command-line option */
142 int __init early_parse_wdt(char *p)
143 {
144 	if (p && strncmp(p, "0", 1) != 0)
145 	       booke_wdt_enabled = 1;
146 
147 	return 0;
148 }
149 early_param("wdt", early_parse_wdt);
150 
151 int __init early_parse_wdt_period (char *p)
152 {
153 	if (p)
154 		booke_wdt_period = simple_strtoul(p, NULL, 0);
155 
156 	return 0;
157 }
158 early_param("wdt_period", early_parse_wdt_period);
159 #endif	/* CONFIG_BOOKE_WDT */
160 
161 /* Checks "l2cr=xxxx" command-line option */
162 int __init ppc_setup_l2cr(char *str)
163 {
164 	if (cpu_has_feature(CPU_FTR_L2CR)) {
165 		unsigned long val = simple_strtoul(str, NULL, 0);
166 		printk(KERN_INFO "l2cr set to %lx\n", val);
167 		_set_L2CR(0);		/* force invalidate by disable cache */
168 		_set_L2CR(val);		/* and enable it */
169 	}
170 	return 1;
171 }
172 __setup("l2cr=", ppc_setup_l2cr);
173 
174 #ifdef CONFIG_GENERIC_NVRAM
175 
176 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
177 unsigned char nvram_read_byte(int addr)
178 {
179 	if (ppc_md.nvram_read_val)
180 		return ppc_md.nvram_read_val(addr);
181 	return 0xff;
182 }
183 EXPORT_SYMBOL(nvram_read_byte);
184 
185 void nvram_write_byte(unsigned char val, int addr)
186 {
187 	if (ppc_md.nvram_write_val)
188 		ppc_md.nvram_write_val(addr, val);
189 }
190 EXPORT_SYMBOL(nvram_write_byte);
191 
192 void nvram_sync(void)
193 {
194 	if (ppc_md.nvram_sync)
195 		ppc_md.nvram_sync();
196 }
197 EXPORT_SYMBOL(nvram_sync);
198 
199 #endif /* CONFIG_NVRAM */
200 
201 static struct cpu cpu_devices[NR_CPUS];
202 
203 int __init ppc_init(void)
204 {
205 	int i;
206 
207 	/* clear the progress line */
208 	if ( ppc_md.progress ) ppc_md.progress("             ", 0xffff);
209 
210 	/* register CPU devices */
211 	for_each_possible_cpu(i)
212 		register_cpu(&cpu_devices[i], i);
213 
214 	/* call platform init */
215 	if (ppc_md.init != NULL) {
216 		ppc_md.init();
217 	}
218 	return 0;
219 }
220 
221 arch_initcall(ppc_init);
222 
223 /* Warning, IO base is not yet inited */
224 void __init setup_arch(char **cmdline_p)
225 {
226 	*cmdline_p = cmd_line;
227 
228 	/* so udelay does something sensible, assume <= 1000 bogomips */
229 	loops_per_jiffy = 500000000 / HZ;
230 
231 	unflatten_device_tree();
232 	check_for_initrd();
233 
234 	if (ppc_md.init_early)
235 		ppc_md.init_early();
236 
237 	find_legacy_serial_ports();
238 
239 	smp_setup_cpu_maps();
240 
241 	/* Register early console */
242 	register_early_udbg_console();
243 
244 	xmon_setup();
245 
246 #if defined(CONFIG_KGDB)
247 	if (ppc_md.kgdb_map_scc)
248 		ppc_md.kgdb_map_scc();
249 	set_debug_traps();
250 	if (strstr(cmd_line, "gdb")) {
251 		if (ppc_md.progress)
252 			ppc_md.progress("setup_arch: kgdb breakpoint", 0x4000);
253 		printk("kgdb breakpoint activated\n");
254 		breakpoint();
255 	}
256 #endif
257 
258 	/*
259 	 * Set cache line size based on type of cpu as a default.
260 	 * Systems with OF can look in the properties on the cpu node(s)
261 	 * for a possibly more accurate value.
262 	 */
263 	if (cpu_has_feature(CPU_FTR_SPLIT_ID_CACHE)) {
264 		dcache_bsize = cur_cpu_spec->dcache_bsize;
265 		icache_bsize = cur_cpu_spec->icache_bsize;
266 		ucache_bsize = 0;
267 	} else
268 		ucache_bsize = dcache_bsize = icache_bsize
269 			= cur_cpu_spec->dcache_bsize;
270 
271 	/* reboot on panic */
272 	panic_timeout = 180;
273 
274 	if (ppc_md.panic)
275 		setup_panic();
276 
277 	init_mm.start_code = PAGE_OFFSET;
278 	init_mm.end_code = (unsigned long) _etext;
279 	init_mm.end_data = (unsigned long) _edata;
280 	init_mm.brk = klimit;
281 
282 	/* set up the bootmem stuff with available memory */
283 	do_init_bootmem();
284 	if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);
285 
286 #ifdef CONFIG_DUMMY_CONSOLE
287 	conswitchp = &dummy_con;
288 #endif
289 
290 	ppc_md.setup_arch();
291 	if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
292 
293 	paging_init();
294 }
295