xref: /linux/arch/sparc/kernel/setup_32.c (revision 3eee9ac24cef892e6883b3669544c6101b70c91e)
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/delay.h>
21 #include <linux/fs.h>
22 #include <linux/seq_file.h>
23 #include <linux/syscalls.h>
24 #include <linux/kdev_t.h>
25 #include <linux/major.h>
26 #include <linux/string.h>
27 #include <linux/init.h>
28 #include <linux/interrupt.h>
29 #include <linux/console.h>
30 #include <linux/spinlock.h>
31 #include <linux/root_dev.h>
32 #include <linux/cpu.h>
33 #include <linux/kdebug.h>
34 #include <linux/export.h>
35 #include <linux/start_kernel.h>
36 #include <uapi/linux/mount.h>
37 
38 #include <asm/io.h>
39 #include <asm/processor.h>
40 #include <asm/oplib.h>
41 #include <asm/page.h>
42 #include <asm/traps.h>
43 #include <asm/vaddrs.h>
44 #include <asm/mbus.h>
45 #include <asm/idprom.h>
46 #include <asm/cpudata.h>
47 #include <asm/setup.h>
48 #include <asm/cacheflush.h>
49 #include <asm/sections.h>
50 
51 #include "kernel.h"
52 
53 /* Typing sync at the prom prompt calls the function pointed to by
54  * romvec->pv_synchook which I set to the following function.
55  * This should sync all filesystems and return, for now it just
56  * prints out pretty messages and returns.
57  */
58 
59 /* Pretty sick eh? */
60 static void prom_sync_me(void)
61 {
62 	unsigned long prom_tbr, flags;
63 
64 	/* XXX Badly broken. FIX! - Anton */
65 	local_irq_save(flags);
66 	__asm__ __volatile__("rd %%tbr, %0\n\t" : "=r" (prom_tbr));
67 	__asm__ __volatile__("wr %0, 0x0, %%tbr\n\t"
68 			     "nop\n\t"
69 			     "nop\n\t"
70 			     "nop\n\t" : : "r" (&trapbase[0]));
71 
72 	prom_printf("PROM SYNC COMMAND...\n");
73 	show_mem();
74 	if (!is_idle_task(current)) {
75 		local_irq_enable();
76 		ksys_sync();
77 		local_irq_disable();
78 	}
79 	prom_printf("Returning to prom\n");
80 
81 	__asm__ __volatile__("wr %0, 0x0, %%tbr\n\t"
82 			     "nop\n\t"
83 			     "nop\n\t"
84 			     "nop\n\t" : : "r" (prom_tbr));
85 	local_irq_restore(flags);
86 }
87 
88 static unsigned int boot_flags __initdata = 0;
89 #define BOOTME_DEBUG  0x1
90 
91 /* Exported for mm/init.c:paging_init. */
92 unsigned long cmdline_memory_size __initdata = 0;
93 
94 /* which CPU booted us (0xff = not set) */
95 unsigned char boot_cpu_id = 0xff; /* 0xff will make it into DATA section... */
96 
97 static void
98 prom_console_write(struct console *con, const char *s, unsigned int n)
99 {
100 	prom_write(s, n);
101 }
102 
103 static struct console prom_early_console = {
104 	.name =		"earlyprom",
105 	.write =	prom_console_write,
106 	.flags =	CON_PRINTBUFFER | CON_BOOT,
107 	.index =	-1,
108 };
109 
110 /*
111  * Process kernel command line switches that are specific to the
112  * SPARC or that require special low-level processing.
113  */
114 static void __init process_switch(char c)
115 {
116 	switch (c) {
117 	case 'd':
118 		boot_flags |= BOOTME_DEBUG;
119 		break;
120 	case 's':
121 		break;
122 	case 'h':
123 		prom_printf("boot_flags_init: Halt!\n");
124 		prom_halt();
125 		break;
126 	case 'p':
127 		prom_early_console.flags &= ~CON_BOOT;
128 		break;
129 	default:
130 		printk("Unknown boot switch (-%c)\n", c);
131 		break;
132 	}
133 }
134 
135 static void __init boot_flags_init(char *commands)
136 {
137 	while (*commands) {
138 		/* Move to the start of the next "argument". */
139 		while (*commands == ' ')
140 			commands++;
141 
142 		/* Process any command switches, otherwise skip it. */
143 		if (*commands == '\0')
144 			break;
145 		if (*commands == '-') {
146 			commands++;
147 			while (*commands && *commands != ' ')
148 				process_switch(*commands++);
149 			continue;
150 		}
151 		if (!strncmp(commands, "mem=", 4)) {
152 			/*
153 			 * "mem=XXX[kKmM] overrides the PROM-reported
154 			 * memory size.
155 			 */
156 			cmdline_memory_size = simple_strtoul(commands + 4,
157 						     &commands, 0);
158 			if (*commands == 'K' || *commands == 'k') {
159 				cmdline_memory_size <<= 10;
160 				commands++;
161 			} else if (*commands=='M' || *commands=='m') {
162 				cmdline_memory_size <<= 20;
163 				commands++;
164 			}
165 		}
166 		while (*commands && *commands != ' ')
167 			commands++;
168 	}
169 }
170 
171 extern unsigned short root_flags;
172 extern unsigned short root_dev;
173 extern unsigned short ram_flags;
174 #define RAMDISK_IMAGE_START_MASK	0x07FF
175 #define RAMDISK_PROMPT_FLAG		0x8000
176 #define RAMDISK_LOAD_FLAG		0x4000
177 
178 extern int root_mountflags;
179 
180 char reboot_command[COMMAND_LINE_SIZE];
181 
182 struct cpuid_patch_entry {
183 	unsigned int	addr;
184 	unsigned int	sun4d[3];
185 	unsigned int	leon[3];
186 };
187 extern struct cpuid_patch_entry __cpuid_patch, __cpuid_patch_end;
188 
189 static void __init per_cpu_patch(void)
190 {
191 	struct cpuid_patch_entry *p;
192 
193 	if (sparc_cpu_model == sun4m) {
194 		/* Nothing to do, this is what the unpatched code
195 		 * targets.
196 		 */
197 		return;
198 	}
199 
200 	p = &__cpuid_patch;
201 	while (p < &__cpuid_patch_end) {
202 		unsigned long addr = p->addr;
203 		unsigned int *insns;
204 
205 		switch (sparc_cpu_model) {
206 		case sun4d:
207 			insns = &p->sun4d[0];
208 			break;
209 
210 		case sparc_leon:
211 			insns = &p->leon[0];
212 			break;
213 		default:
214 			prom_printf("Unknown cpu type, halting.\n");
215 			prom_halt();
216 		}
217 		*(unsigned int *) (addr + 0) = insns[0];
218 		flushi(addr + 0);
219 		*(unsigned int *) (addr + 4) = insns[1];
220 		flushi(addr + 4);
221 		*(unsigned int *) (addr + 8) = insns[2];
222 		flushi(addr + 8);
223 
224 		p++;
225 	}
226 }
227 
228 struct leon_1insn_patch_entry {
229 	unsigned int addr;
230 	unsigned int insn;
231 };
232 
233 enum sparc_cpu sparc_cpu_model;
234 EXPORT_SYMBOL(sparc_cpu_model);
235 
236 static __init void leon_patch(void)
237 {
238 	struct leon_1insn_patch_entry *start = (void *)__leon_1insn_patch;
239 	struct leon_1insn_patch_entry *end = (void *)__leon_1insn_patch_end;
240 
241 	/* Default instruction is leon - no patching */
242 	if (sparc_cpu_model == sparc_leon)
243 		return;
244 
245 	while (start < end) {
246 		unsigned long addr = start->addr;
247 
248 		*(unsigned int *)(addr) = start->insn;
249 		flushi(addr);
250 
251 		start++;
252 	}
253 }
254 
255 struct tt_entry *sparc_ttable;
256 
257 /* Called from head_32.S - before we have setup anything
258  * in the kernel. Be very careful with what you do here.
259  */
260 void __init sparc32_start_kernel(struct linux_romvec *rp)
261 {
262 	prom_init(rp);
263 
264 	/* Set sparc_cpu_model */
265 	sparc_cpu_model = sun_unknown;
266 	if (!strcmp(&cputypval[0], "sun4m"))
267 		sparc_cpu_model = sun4m;
268 	if (!strcmp(&cputypval[0], "sun4s"))
269 		sparc_cpu_model = sun4m; /* CP-1200 with PROM 2.30 -E */
270 	if (!strcmp(&cputypval[0], "sun4d"))
271 		sparc_cpu_model = sun4d;
272 	if (!strcmp(&cputypval[0], "sun4e"))
273 		sparc_cpu_model = sun4e;
274 	if (!strcmp(&cputypval[0], "sun4u"))
275 		sparc_cpu_model = sun4u;
276 	if (!strncmp(&cputypval[0], "leon" , 4))
277 		sparc_cpu_model = sparc_leon;
278 
279 	leon_patch();
280 	start_kernel();
281 }
282 
283 void __init setup_arch(char **cmdline_p)
284 {
285 	int i;
286 	unsigned long highest_paddr;
287 
288 	sparc_ttable = &trapbase[0];
289 
290 	/* Initialize PROM console and command line. */
291 	*cmdline_p = prom_getbootargs();
292 	strscpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);
293 	parse_early_param();
294 
295 	boot_flags_init(*cmdline_p);
296 
297 	register_console(&prom_early_console);
298 
299 	switch(sparc_cpu_model) {
300 	case sun4m:
301 		pr_info("ARCH: SUN4M\n");
302 		break;
303 	case sun4d:
304 		pr_info("ARCH: SUN4D\n");
305 		break;
306 	case sun4e:
307 		pr_info("ARCH: SUN4E\n");
308 		break;
309 	case sun4u:
310 		pr_info("ARCH: SUN4U\n");
311 		break;
312 	case sparc_leon:
313 		pr_info("ARCH: LEON\n");
314 		break;
315 	default:
316 		pr_info("ARCH: UNKNOWN!\n");
317 		break;
318 	}
319 
320 	idprom_init();
321 	load_mmu();
322 
323 	phys_base = 0xffffffffUL;
324 	highest_paddr = 0UL;
325 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
326 		unsigned long top;
327 
328 		if (sp_banks[i].base_addr < phys_base)
329 			phys_base = sp_banks[i].base_addr;
330 		top = sp_banks[i].base_addr +
331 			sp_banks[i].num_bytes;
332 		if (highest_paddr < top)
333 			highest_paddr = top;
334 	}
335 	pfn_base = phys_base >> PAGE_SHIFT;
336 
337 	if (!root_flags)
338 		root_mountflags &= ~MS_RDONLY;
339 	ROOT_DEV = old_decode_dev(root_dev);
340 #ifdef CONFIG_BLK_DEV_RAM
341 	rd_image_start = ram_flags & RAMDISK_IMAGE_START_MASK;
342 #endif
343 
344 	prom_setsync(prom_sync_me);
345 
346 	if((boot_flags & BOOTME_DEBUG) && (linux_dbvec != NULL) &&
347 	   ((*(short *)linux_dbvec) != -1)) {
348 		printk("Booted under KADB. Syncing trap table.\n");
349 		(*(linux_dbvec->teach_debugger))();
350 	}
351 
352 	/* Run-time patch instructions to match the cpu model */
353 	per_cpu_patch();
354 
355 	paging_init();
356 
357 	smp_setup_cpu_possible_map();
358 }
359 
360 extern int stop_a_enabled;
361 
362 void sun_do_break(void)
363 {
364 	if (!stop_a_enabled)
365 		return;
366 
367 	printk("\n");
368 	flush_user_windows();
369 
370 	prom_cmdline();
371 }
372 EXPORT_SYMBOL(sun_do_break);
373 
374 int stop_a_enabled = 1;
375 
376 static int __init topology_init(void)
377 {
378 	int i, ncpus, err;
379 
380 	/* Count the number of physically present processors in
381 	 * the machine, even on uniprocessor, so that /proc/cpuinfo
382 	 * output is consistent with 2.4.x
383 	 */
384 	ncpus = 0;
385 	while (!cpu_find_by_instance(ncpus, NULL, NULL))
386 		ncpus++;
387 	ncpus_probed = ncpus;
388 
389 	err = 0;
390 	for_each_online_cpu(i) {
391 		struct cpu *p = kzalloc(sizeof(*p), GFP_KERNEL);
392 		if (!p)
393 			err = -ENOMEM;
394 		else
395 			register_cpu(p, i);
396 	}
397 
398 	return err;
399 }
400 
401 subsys_initcall(topology_init);
402 
403 #if defined(CONFIG_SPARC32) && !defined(CONFIG_SMP)
404 void __init arch_cpu_finalize_init(void)
405 {
406 	cpu_data(0).udelay_val = loops_per_jiffy;
407 }
408 #endif
409