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