xref: /openbmc/linux/arch/sparc/kernel/setup_32.c (revision 1a59d1b8)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/arch/sparc/kernel/setup.c
4  *
5  *  Copyright (C) 1995  David S. Miller (davem@caip.rutgers.edu)
6  *  Copyright (C) 2000  Anton Blanchard (anton@samba.org)
7  */
8 
9 #include <linux/errno.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
12 #include <linux/mm.h>
13 #include <linux/stddef.h>
14 #include <linux/unistd.h>
15 #include <linux/ptrace.h>
16 #include <linux/slab.h>
17 #include <linux/initrd.h>
18 #include <asm/smp.h>
19 #include <linux/user.h>
20 #include <linux/screen_info.h>
21 #include <linux/delay.h>
22 #include <linux/fs.h>
23 #include <linux/seq_file.h>
24 #include <linux/syscalls.h>
25 #include <linux/kdev_t.h>
26 #include <linux/major.h>
27 #include <linux/string.h>
28 #include <linux/init.h>
29 #include <linux/interrupt.h>
30 #include <linux/console.h>
31 #include <linux/spinlock.h>
32 #include <linux/root_dev.h>
33 #include <linux/cpu.h>
34 #include <linux/kdebug.h>
35 #include <linux/export.h>
36 #include <linux/start_kernel.h>
37 #include <uapi/linux/mount.h>
38 
39 #include <asm/io.h>
40 #include <asm/processor.h>
41 #include <asm/oplib.h>
42 #include <asm/page.h>
43 #include <asm/pgtable.h>
44 #include <asm/traps.h>
45 #include <asm/vaddrs.h>
46 #include <asm/mbus.h>
47 #include <asm/idprom.h>
48 #include <asm/cpudata.h>
49 #include <asm/setup.h>
50 #include <asm/cacheflush.h>
51 #include <asm/sections.h>
52 
53 #include "kernel.h"
54 
55 struct screen_info screen_info = {
56 	0, 0,			/* orig-x, orig-y */
57 	0,			/* unused */
58 	0,			/* orig-video-page */
59 	0,			/* orig-video-mode */
60 	128,			/* orig-video-cols */
61 	0,0,0,			/* ega_ax, ega_bx, ega_cx */
62 	54,			/* orig-video-lines */
63 	0,                      /* orig-video-isVGA */
64 	16                      /* orig-video-points */
65 };
66 
67 /* Typing sync at the prom prompt calls the function pointed to by
68  * romvec->pv_synchook which I set to the following function.
69  * This should sync all filesystems and return, for now it just
70  * prints out pretty messages and returns.
71  */
72 
73 /* Pretty sick eh? */
74 static void prom_sync_me(void)
75 {
76 	unsigned long prom_tbr, flags;
77 
78 	/* XXX Badly broken. FIX! - Anton */
79 	local_irq_save(flags);
80 	__asm__ __volatile__("rd %%tbr, %0\n\t" : "=r" (prom_tbr));
81 	__asm__ __volatile__("wr %0, 0x0, %%tbr\n\t"
82 			     "nop\n\t"
83 			     "nop\n\t"
84 			     "nop\n\t" : : "r" (&trapbase));
85 
86 	prom_printf("PROM SYNC COMMAND...\n");
87 	show_free_areas(0, NULL);
88 	if (!is_idle_task(current)) {
89 		local_irq_enable();
90 		ksys_sync();
91 		local_irq_disable();
92 	}
93 	prom_printf("Returning to prom\n");
94 
95 	__asm__ __volatile__("wr %0, 0x0, %%tbr\n\t"
96 			     "nop\n\t"
97 			     "nop\n\t"
98 			     "nop\n\t" : : "r" (prom_tbr));
99 	local_irq_restore(flags);
100 }
101 
102 static unsigned int boot_flags __initdata = 0;
103 #define BOOTME_DEBUG  0x1
104 
105 /* Exported for mm/init.c:paging_init. */
106 unsigned long cmdline_memory_size __initdata = 0;
107 
108 /* which CPU booted us (0xff = not set) */
109 unsigned char boot_cpu_id = 0xff; /* 0xff will make it into DATA section... */
110 
111 static void
112 prom_console_write(struct console *con, const char *s, unsigned int n)
113 {
114 	prom_write(s, n);
115 }
116 
117 static struct console prom_early_console = {
118 	.name =		"earlyprom",
119 	.write =	prom_console_write,
120 	.flags =	CON_PRINTBUFFER | CON_BOOT,
121 	.index =	-1,
122 };
123 
124 /*
125  * Process kernel command line switches that are specific to the
126  * SPARC or that require special low-level processing.
127  */
128 static void __init process_switch(char c)
129 {
130 	switch (c) {
131 	case 'd':
132 		boot_flags |= BOOTME_DEBUG;
133 		break;
134 	case 's':
135 		break;
136 	case 'h':
137 		prom_printf("boot_flags_init: Halt!\n");
138 		prom_halt();
139 		break;
140 	case 'p':
141 		prom_early_console.flags &= ~CON_BOOT;
142 		break;
143 	default:
144 		printk("Unknown boot switch (-%c)\n", c);
145 		break;
146 	}
147 }
148 
149 static void __init boot_flags_init(char *commands)
150 {
151 	while (*commands) {
152 		/* Move to the start of the next "argument". */
153 		while (*commands == ' ')
154 			commands++;
155 
156 		/* Process any command switches, otherwise skip it. */
157 		if (*commands == '\0')
158 			break;
159 		if (*commands == '-') {
160 			commands++;
161 			while (*commands && *commands != ' ')
162 				process_switch(*commands++);
163 			continue;
164 		}
165 		if (!strncmp(commands, "mem=", 4)) {
166 			/*
167 			 * "mem=XXX[kKmM] overrides the PROM-reported
168 			 * memory size.
169 			 */
170 			cmdline_memory_size = simple_strtoul(commands + 4,
171 						     &commands, 0);
172 			if (*commands == 'K' || *commands == 'k') {
173 				cmdline_memory_size <<= 10;
174 				commands++;
175 			} else if (*commands=='M' || *commands=='m') {
176 				cmdline_memory_size <<= 20;
177 				commands++;
178 			}
179 		}
180 		while (*commands && *commands != ' ')
181 			commands++;
182 	}
183 }
184 
185 extern unsigned short root_flags;
186 extern unsigned short root_dev;
187 extern unsigned short ram_flags;
188 #define RAMDISK_IMAGE_START_MASK	0x07FF
189 #define RAMDISK_PROMPT_FLAG		0x8000
190 #define RAMDISK_LOAD_FLAG		0x4000
191 
192 extern int root_mountflags;
193 
194 char reboot_command[COMMAND_LINE_SIZE];
195 
196 struct cpuid_patch_entry {
197 	unsigned int	addr;
198 	unsigned int	sun4d[3];
199 	unsigned int	leon[3];
200 };
201 extern struct cpuid_patch_entry __cpuid_patch, __cpuid_patch_end;
202 
203 static void __init per_cpu_patch(void)
204 {
205 	struct cpuid_patch_entry *p;
206 
207 	if (sparc_cpu_model == sun4m) {
208 		/* Nothing to do, this is what the unpatched code
209 		 * targets.
210 		 */
211 		return;
212 	}
213 
214 	p = &__cpuid_patch;
215 	while (p < &__cpuid_patch_end) {
216 		unsigned long addr = p->addr;
217 		unsigned int *insns;
218 
219 		switch (sparc_cpu_model) {
220 		case sun4d:
221 			insns = &p->sun4d[0];
222 			break;
223 
224 		case sparc_leon:
225 			insns = &p->leon[0];
226 			break;
227 		default:
228 			prom_printf("Unknown cpu type, halting.\n");
229 			prom_halt();
230 		}
231 		*(unsigned int *) (addr + 0) = insns[0];
232 		flushi(addr + 0);
233 		*(unsigned int *) (addr + 4) = insns[1];
234 		flushi(addr + 4);
235 		*(unsigned int *) (addr + 8) = insns[2];
236 		flushi(addr + 8);
237 
238 		p++;
239 	}
240 }
241 
242 struct leon_1insn_patch_entry {
243 	unsigned int addr;
244 	unsigned int insn;
245 };
246 
247 enum sparc_cpu sparc_cpu_model;
248 EXPORT_SYMBOL(sparc_cpu_model);
249 
250 static __init void leon_patch(void)
251 {
252 	struct leon_1insn_patch_entry *start = (void *)__leon_1insn_patch;
253 	struct leon_1insn_patch_entry *end = (void *)__leon_1insn_patch_end;
254 
255 	/* Default instruction is leon - no patching */
256 	if (sparc_cpu_model == sparc_leon)
257 		return;
258 
259 	while (start < end) {
260 		unsigned long addr = start->addr;
261 
262 		*(unsigned int *)(addr) = start->insn;
263 		flushi(addr);
264 
265 		start++;
266 	}
267 }
268 
269 struct tt_entry *sparc_ttable;
270 static struct pt_regs fake_swapper_regs;
271 
272 /* Called from head_32.S - before we have setup anything
273  * in the kernel. Be very careful with what you do here.
274  */
275 void __init sparc32_start_kernel(struct linux_romvec *rp)
276 {
277 	prom_init(rp);
278 
279 	/* Set sparc_cpu_model */
280 	sparc_cpu_model = sun_unknown;
281 	if (!strcmp(&cputypval[0], "sun4m"))
282 		sparc_cpu_model = sun4m;
283 	if (!strcmp(&cputypval[0], "sun4s"))
284 		sparc_cpu_model = sun4m; /* CP-1200 with PROM 2.30 -E */
285 	if (!strcmp(&cputypval[0], "sun4d"))
286 		sparc_cpu_model = sun4d;
287 	if (!strcmp(&cputypval[0], "sun4e"))
288 		sparc_cpu_model = sun4e;
289 	if (!strcmp(&cputypval[0], "sun4u"))
290 		sparc_cpu_model = sun4u;
291 	if (!strncmp(&cputypval[0], "leon" , 4))
292 		sparc_cpu_model = sparc_leon;
293 
294 	leon_patch();
295 	start_kernel();
296 }
297 
298 void __init setup_arch(char **cmdline_p)
299 {
300 	int i;
301 	unsigned long highest_paddr;
302 
303 	sparc_ttable = &trapbase;
304 
305 	/* Initialize PROM console and command line. */
306 	*cmdline_p = prom_getbootargs();
307 	strlcpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
308 	parse_early_param();
309 
310 	boot_flags_init(*cmdline_p);
311 
312 	register_console(&prom_early_console);
313 
314 	switch(sparc_cpu_model) {
315 	case sun4m:
316 		pr_info("ARCH: SUN4M\n");
317 		break;
318 	case sun4d:
319 		pr_info("ARCH: SUN4D\n");
320 		break;
321 	case sun4e:
322 		pr_info("ARCH: SUN4E\n");
323 		break;
324 	case sun4u:
325 		pr_info("ARCH: SUN4U\n");
326 		break;
327 	case sparc_leon:
328 		pr_info("ARCH: LEON\n");
329 		break;
330 	default:
331 		pr_info("ARCH: UNKNOWN!\n");
332 		break;
333 	}
334 
335 #ifdef CONFIG_DUMMY_CONSOLE
336 	conswitchp = &dummy_con;
337 #endif
338 
339 	idprom_init();
340 	load_mmu();
341 
342 	phys_base = 0xffffffffUL;
343 	highest_paddr = 0UL;
344 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
345 		unsigned long top;
346 
347 		if (sp_banks[i].base_addr < phys_base)
348 			phys_base = sp_banks[i].base_addr;
349 		top = sp_banks[i].base_addr +
350 			sp_banks[i].num_bytes;
351 		if (highest_paddr < top)
352 			highest_paddr = top;
353 	}
354 	pfn_base = phys_base >> PAGE_SHIFT;
355 
356 	if (!root_flags)
357 		root_mountflags &= ~MS_RDONLY;
358 	ROOT_DEV = old_decode_dev(root_dev);
359 #ifdef CONFIG_BLK_DEV_RAM
360 	rd_image_start = ram_flags & RAMDISK_IMAGE_START_MASK;
361 	rd_prompt = ((ram_flags & RAMDISK_PROMPT_FLAG) != 0);
362 	rd_doload = ((ram_flags & RAMDISK_LOAD_FLAG) != 0);
363 #endif
364 
365 	prom_setsync(prom_sync_me);
366 
367 	if((boot_flags & BOOTME_DEBUG) && (linux_dbvec != NULL) &&
368 	   ((*(short *)linux_dbvec) != -1)) {
369 		printk("Booted under KADB. Syncing trap table.\n");
370 		(*(linux_dbvec->teach_debugger))();
371 	}
372 
373 	init_task.thread.kregs = &fake_swapper_regs;
374 
375 	/* Run-time patch instructions to match the cpu model */
376 	per_cpu_patch();
377 
378 	paging_init();
379 
380 	smp_setup_cpu_possible_map();
381 }
382 
383 extern int stop_a_enabled;
384 
385 void sun_do_break(void)
386 {
387 	if (!stop_a_enabled)
388 		return;
389 
390 	printk("\n");
391 	flush_user_windows();
392 
393 	prom_cmdline();
394 }
395 EXPORT_SYMBOL(sun_do_break);
396 
397 int stop_a_enabled = 1;
398 
399 static int __init topology_init(void)
400 {
401 	int i, ncpus, err;
402 
403 	/* Count the number of physically present processors in
404 	 * the machine, even on uniprocessor, so that /proc/cpuinfo
405 	 * output is consistent with 2.4.x
406 	 */
407 	ncpus = 0;
408 	while (!cpu_find_by_instance(ncpus, NULL, NULL))
409 		ncpus++;
410 	ncpus_probed = ncpus;
411 
412 	err = 0;
413 	for_each_online_cpu(i) {
414 		struct cpu *p = kzalloc(sizeof(*p), GFP_KERNEL);
415 		if (!p)
416 			err = -ENOMEM;
417 		else
418 			register_cpu(p, i);
419 	}
420 
421 	return err;
422 }
423 
424 subsys_initcall(topology_init);
425