xref: /openbmc/linux/arch/powerpc/kernel/setup_32.c (revision c21b37f6)
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 EXPORT_SYMBOL(vgacon_remap_base);
69 #endif
70 
71 /*
72  * These are used in binfmt_elf.c to put aux entries on the stack
73  * for each elf executable being started.
74  */
75 int dcache_bsize;
76 int icache_bsize;
77 int ucache_bsize;
78 
79 /*
80  * We're called here very early in the boot.  We determine the machine
81  * type and call the appropriate low-level setup functions.
82  *  -- Cort <cort@fsmlabs.com>
83  *
84  * Note that the kernel may be running at an address which is different
85  * from the address that it was linked at, so we must use RELOC/PTRRELOC
86  * to access static data (including strings).  -- paulus
87  */
88 unsigned long __init early_init(unsigned long dt_ptr)
89 {
90 	unsigned long offset = reloc_offset();
91 	struct cpu_spec *spec;
92 
93 	/* First zero the BSS -- use memset_io, some platforms don't have
94 	 * caches on yet */
95 	memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
96 			__bss_stop - __bss_start);
97 
98 	/*
99 	 * Identify the CPU type and fix up code sections
100 	 * that depend on which cpu we have.
101 	 */
102 	spec = identify_cpu(offset, mfspr(SPRN_PVR));
103 
104 	do_feature_fixups(spec->cpu_features,
105 			  PTRRELOC(&__start___ftr_fixup),
106 			  PTRRELOC(&__stop___ftr_fixup));
107 
108 	return KERNELBASE + offset;
109 }
110 
111 
112 /*
113  * Find out what kind of machine we're on and save any data we need
114  * from the early boot process (devtree is copied on pmac by prom_init()).
115  * This is called very early on the boot process, after a minimal
116  * MMU environment has been set up but before MMU_init is called.
117  */
118 void __init machine_init(unsigned long dt_ptr, unsigned long phys)
119 {
120 	/* Enable early debugging if any specified (see udbg.h) */
121 	udbg_early_init();
122 
123 	/* Do some early initialization based on the flat device tree */
124 	early_init_devtree(__va(dt_ptr));
125 
126 	probe_machine();
127 
128 #ifdef CONFIG_6xx
129 	if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
130 	    cpu_has_feature(CPU_FTR_CAN_NAP))
131 		ppc_md.power_save = ppc6xx_idle;
132 #endif
133 
134 	if (ppc_md.progress)
135 		ppc_md.progress("id mach(): done", 0x200);
136 }
137 
138 #ifdef CONFIG_BOOKE_WDT
139 /* Checks wdt=x and wdt_period=xx command-line option */
140 int __init early_parse_wdt(char *p)
141 {
142 	if (p && strncmp(p, "0", 1) != 0)
143 	       booke_wdt_enabled = 1;
144 
145 	return 0;
146 }
147 early_param("wdt", early_parse_wdt);
148 
149 int __init early_parse_wdt_period (char *p)
150 {
151 	if (p)
152 		booke_wdt_period = simple_strtoul(p, NULL, 0);
153 
154 	return 0;
155 }
156 early_param("wdt_period", early_parse_wdt_period);
157 #endif	/* CONFIG_BOOKE_WDT */
158 
159 /* Checks "l2cr=xxxx" command-line option */
160 int __init ppc_setup_l2cr(char *str)
161 {
162 	if (cpu_has_feature(CPU_FTR_L2CR)) {
163 		unsigned long val = simple_strtoul(str, NULL, 0);
164 		printk(KERN_INFO "l2cr set to %lx\n", val);
165 		_set_L2CR(0);		/* force invalidate by disable cache */
166 		_set_L2CR(val);		/* and enable it */
167 	}
168 	return 1;
169 }
170 __setup("l2cr=", ppc_setup_l2cr);
171 
172 #ifdef CONFIG_GENERIC_NVRAM
173 
174 /* Generic nvram hooks used by drivers/char/gen_nvram.c */
175 unsigned char nvram_read_byte(int addr)
176 {
177 	if (ppc_md.nvram_read_val)
178 		return ppc_md.nvram_read_val(addr);
179 	return 0xff;
180 }
181 EXPORT_SYMBOL(nvram_read_byte);
182 
183 void nvram_write_byte(unsigned char val, int addr)
184 {
185 	if (ppc_md.nvram_write_val)
186 		ppc_md.nvram_write_val(addr, val);
187 }
188 EXPORT_SYMBOL(nvram_write_byte);
189 
190 void nvram_sync(void)
191 {
192 	if (ppc_md.nvram_sync)
193 		ppc_md.nvram_sync();
194 }
195 EXPORT_SYMBOL(nvram_sync);
196 
197 #endif /* CONFIG_NVRAM */
198 
199 static DEFINE_PER_CPU(struct cpu, cpu_devices);
200 
201 int __init ppc_init(void)
202 {
203 	int cpu;
204 
205 	/* clear the progress line */
206 	if (ppc_md.progress)
207 		ppc_md.progress("             ", 0xffff);
208 
209 	/* register CPU devices */
210 	for_each_possible_cpu(cpu) {
211 		struct cpu *c = &per_cpu(cpu_devices, cpu);
212 		c->hotpluggable = 1;
213 		register_cpu(c, cpu);
214 	}
215 
216 	/* call platform init */
217 	if (ppc_md.init != NULL) {
218 		ppc_md.init();
219 	}
220 	return 0;
221 }
222 
223 arch_initcall(ppc_init);
224 
225 /* Warning, IO base is not yet inited */
226 void __init setup_arch(char **cmdline_p)
227 {
228 	*cmdline_p = cmd_line;
229 
230 	/* so udelay does something sensible, assume <= 1000 bogomips */
231 	loops_per_jiffy = 500000000 / HZ;
232 
233 	unflatten_device_tree();
234 	check_for_initrd();
235 
236 	if (ppc_md.init_early)
237 		ppc_md.init_early();
238 
239 	find_legacy_serial_ports();
240 
241 	smp_setup_cpu_maps();
242 
243 	/* Register early console */
244 	register_early_udbg_console();
245 
246 	xmon_setup();
247 
248 #if defined(CONFIG_KGDB)
249 	if (ppc_md.kgdb_map_scc)
250 		ppc_md.kgdb_map_scc();
251 	set_debug_traps();
252 	if (strstr(cmd_line, "gdb")) {
253 		if (ppc_md.progress)
254 			ppc_md.progress("setup_arch: kgdb breakpoint", 0x4000);
255 		printk("kgdb breakpoint activated\n");
256 		breakpoint();
257 	}
258 #endif
259 
260 	/*
261 	 * Set cache line size based on type of cpu as a default.
262 	 * Systems with OF can look in the properties on the cpu node(s)
263 	 * for a possibly more accurate value.
264 	 */
265 	dcache_bsize = cur_cpu_spec->dcache_bsize;
266 	icache_bsize = cur_cpu_spec->icache_bsize;
267 	ucache_bsize = 0;
268 	if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
269 		ucache_bsize = icache_bsize = 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