xref: /openbmc/linux/arch/arc/kernel/setup.c (revision 12eb4683)
1 /*
2  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/seq_file.h>
10 #include <linux/fs.h>
11 #include <linux/delay.h>
12 #include <linux/root_dev.h>
13 #include <linux/console.h>
14 #include <linux/module.h>
15 #include <linux/cpu.h>
16 #include <linux/of_fdt.h>
17 #include <linux/cache.h>
18 #include <asm/sections.h>
19 #include <asm/arcregs.h>
20 #include <asm/tlb.h>
21 #include <asm/setup.h>
22 #include <asm/page.h>
23 #include <asm/irq.h>
24 #include <asm/unwind.h>
25 #include <asm/clk.h>
26 #include <asm/mach_desc.h>
27 
28 #define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
29 
30 int running_on_hw = 1;	/* vs. on ISS */
31 
32 char __initdata command_line[COMMAND_LINE_SIZE];
33 const struct machine_desc *machine_desc;
34 
35 struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
36 
37 struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
38 
39 static void read_arc_build_cfg_regs(void)
40 {
41 	struct bcr_perip uncached_space;
42 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
43 	FIX_PTR(cpu);
44 
45 	READ_BCR(AUX_IDENTITY, cpu->core);
46 
47 	cpu->timers = read_aux_reg(ARC_REG_TIMERS_BCR);
48 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
49 
50 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
51 	cpu->uncached_base = uncached_space.start << 24;
52 
53 	cpu->extn.mul = read_aux_reg(ARC_REG_MUL_BCR);
54 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR);
55 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR);
56 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR);
57 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR);
58 	READ_BCR(ARC_REG_MAC_BCR, cpu->extn_mac_mul);
59 
60 	cpu->extn.ext_arith = read_aux_reg(ARC_REG_EXTARITH_BCR);
61 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR);
62 
63 	/* Note that we read the CCM BCRs independent of kernel config
64 	 * This is to catch the cases where user doesn't know that
65 	 * CCMs are present in hardware build
66 	 */
67 	{
68 		struct bcr_iccm iccm;
69 		struct bcr_dccm dccm;
70 		struct bcr_dccm_base dccm_base;
71 		unsigned int bcr_32bit_val;
72 
73 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
74 		if (bcr_32bit_val) {
75 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
76 			cpu->iccm.base_addr = iccm.base << 16;
77 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
78 		}
79 
80 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
81 		if (bcr_32bit_val) {
82 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
83 			cpu->dccm.sz = 0x800 << (dccm.sz);
84 
85 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
86 			cpu->dccm.base_addr = dccm_base.addr << 8;
87 		}
88 	}
89 
90 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
91 
92 	read_decode_mmu_bcr();
93 	read_decode_cache_bcr();
94 
95 	READ_BCR(ARC_REG_FP_BCR, cpu->fp);
96 	READ_BCR(ARC_REG_DPFP_BCR, cpu->dpfp);
97 }
98 
99 static const struct cpuinfo_data arc_cpu_tbl[] = {
100 	{ {0x10, "ARCTangent A5"}, 0x1F},
101 	{ {0x20, "ARC 600"      }, 0x2F},
102 	{ {0x30, "ARC 700"      }, 0x33},
103 	{ {0x34, "ARC 700 R4.10"}, 0x34},
104 	{ {0x00, NULL		} }
105 };
106 
107 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
108 {
109 	int n = 0;
110 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
111 	struct bcr_identity *core = &cpu->core;
112 	const struct cpuinfo_data *tbl;
113 	int be = 0;
114 #ifdef CONFIG_CPU_BIG_ENDIAN
115 	be = 1;
116 #endif
117 	FIX_PTR(cpu);
118 
119 	n += scnprintf(buf + n, len - n,
120 		       "\nARC IDENTITY\t: Family [%#02x]"
121 		       " Cpu-id [%#02x] Chip-id [%#4x]\n",
122 		       core->family, core->cpu_id,
123 		       core->chip_id);
124 
125 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
126 		if ((core->family >= tbl->info.id) &&
127 		    (core->family <= tbl->up_range)) {
128 			n += scnprintf(buf + n, len - n,
129 				       "processor\t: %s %s\n",
130 				       tbl->info.str,
131 				       be ? "[Big Endian]" : "");
132 			break;
133 		}
134 	}
135 
136 	if (tbl->info.id == 0)
137 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
138 
139 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
140 		       (unsigned int)(arc_get_core_freq() / 1000000),
141 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
142 
143 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s %s\n",
144 		       (cpu->timers & 0x200) ? "TIMER1" : "",
145 		       (cpu->timers & 0x100) ? "TIMER0" : "");
146 
147 	n += scnprintf(buf + n, len - n, "Vect Tbl Base\t: %#x\n",
148 		       cpu->vec_base);
149 
150 	n += scnprintf(buf + n, len - n, "UNCACHED Base\t: %#x\n",
151 		       cpu->uncached_base);
152 
153 	return buf;
154 }
155 
156 static const struct id_to_str mul_type_nm[] = {
157 	{ 0x0, "N/A"},
158 	{ 0x1, "32x32 (spl Result Reg)" },
159 	{ 0x2, "32x32 (ANY Result Reg)" }
160 };
161 
162 static const struct id_to_str mac_mul_nm[] = {
163 	{0x0, "N/A"},
164 	{0x1, "N/A"},
165 	{0x2, "Dual 16 x 16"},
166 	{0x3, "N/A"},
167 	{0x4, "32x16"},
168 	{0x5, "N/A"},
169 	{0x6, "Dual 16x16 and 32x16"}
170 };
171 
172 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
173 {
174 	int n = 0;
175 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
176 
177 	FIX_PTR(cpu);
178 #define IS_AVAIL1(var, str)	((var) ? str : "")
179 #define IS_AVAIL2(var, str)	((var == 0x2) ? str : "")
180 #define IS_USED(cfg)		(IS_ENABLED(cfg) ? "(in-use)" : "(not used)")
181 
182 	n += scnprintf(buf + n, len - n,
183 		       "Extn [700-Base]\t: %s %s %s %s %s %s\n",
184 		       IS_AVAIL2(cpu->extn.norm, "norm,"),
185 		       IS_AVAIL2(cpu->extn.barrel, "barrel-shift,"),
186 		       IS_AVAIL1(cpu->extn.swap, "swap,"),
187 		       IS_AVAIL2(cpu->extn.minmax, "minmax,"),
188 		       IS_AVAIL1(cpu->extn.crc, "crc,"),
189 		       IS_AVAIL2(cpu->extn.ext_arith, "ext-arith"));
190 
191 	n += scnprintf(buf + n, len - n, "Extn [700-MPY]\t: %s",
192 		       mul_type_nm[cpu->extn.mul].str);
193 
194 	n += scnprintf(buf + n, len - n, "   MAC MPY: %s\n",
195 		       mac_mul_nm[cpu->extn_mac_mul.type].str);
196 
197 	if (cpu->core.family == 0x34) {
198 		n += scnprintf(buf + n, len - n,
199 		"Extn [700-4.10]\t: LLOCK/SCOND %s, SWAPE %s, RTSC %s\n",
200 			       IS_USED(CONFIG_ARC_HAS_LLSC),
201 			       IS_USED(CONFIG_ARC_HAS_SWAPE),
202 			       IS_USED(CONFIG_ARC_HAS_RTSC));
203 	}
204 
205 	n += scnprintf(buf + n, len - n, "Extn [CCM]\t: %s",
206 		       !(cpu->dccm.sz || cpu->iccm.sz) ? "N/A" : "");
207 
208 	if (cpu->dccm.sz)
209 		n += scnprintf(buf + n, len - n, "DCCM: @ %x, %d KB ",
210 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz));
211 
212 	if (cpu->iccm.sz)
213 		n += scnprintf(buf + n, len - n, "ICCM: @ %x, %d KB",
214 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
215 
216 	n += scnprintf(buf + n, len - n, "\nExtn [FPU]\t: %s",
217 		       !(cpu->fp.ver || cpu->dpfp.ver) ? "N/A" : "");
218 
219 	if (cpu->fp.ver)
220 		n += scnprintf(buf + n, len - n, "SP [v%d] %s",
221 			       cpu->fp.ver, cpu->fp.fast ? "(fast)" : "");
222 
223 	if (cpu->dpfp.ver)
224 		n += scnprintf(buf + n, len - n, "DP [v%d] %s",
225 			       cpu->dpfp.ver, cpu->dpfp.fast ? "(fast)" : "");
226 
227 	n += scnprintf(buf + n, len - n, "\n");
228 
229 	n += scnprintf(buf + n, len - n,
230 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
231 
232 	return buf;
233 }
234 
235 static void arc_chk_ccms(void)
236 {
237 #if defined(CONFIG_ARC_HAS_DCCM) || defined(CONFIG_ARC_HAS_ICCM)
238 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
239 
240 #ifdef CONFIG_ARC_HAS_DCCM
241 	/*
242 	 * DCCM can be arbit placed in hardware.
243 	 * Make sure it's placement/sz matches what Linux is built with
244 	 */
245 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
246 		panic("Linux built with incorrect DCCM Base address\n");
247 
248 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
249 		panic("Linux built with incorrect DCCM Size\n");
250 #endif
251 
252 #ifdef CONFIG_ARC_HAS_ICCM
253 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
254 		panic("Linux built with incorrect ICCM Size\n");
255 #endif
256 #endif
257 }
258 
259 /*
260  * Ensure that FP hardware and kernel config match
261  * -If hardware contains DPFP, kernel needs to save/restore FPU state
262  *  across context switches
263  * -If hardware lacks DPFP, but kernel configured to save FPU state then
264  *  kernel trying to access non-existant DPFP regs will crash
265  *
266  * We only check for Dbl precision Floating Point, because only DPFP
267  * hardware has dedicated regs which need to be saved/restored on ctx-sw
268  * (Single Precision uses core regs), thus kernel is kind of oblivious to it
269  */
270 static void arc_chk_fpu(void)
271 {
272 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
273 
274 	if (cpu->dpfp.ver) {
275 #ifndef CONFIG_ARC_FPU_SAVE_RESTORE
276 		pr_warn("DPFP support broken in this kernel...\n");
277 #endif
278 	} else {
279 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
280 		panic("H/w lacks DPFP support, apps won't work\n");
281 #endif
282 	}
283 }
284 
285 /*
286  * Initialize and setup the processor core
287  * This is called by all the CPUs thus should not do special case stuff
288  *    such as only for boot CPU etc
289  */
290 
291 void setup_processor(void)
292 {
293 	char str[512];
294 	int cpu_id = smp_processor_id();
295 
296 	read_arc_build_cfg_regs();
297 	arc_init_IRQ();
298 
299 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
300 
301 	arc_mmu_init();
302 	arc_cache_init();
303 	arc_chk_ccms();
304 
305 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
306 
307 #ifdef CONFIG_SMP
308 	printk(arc_platform_smp_cpuinfo());
309 #endif
310 
311 	arc_chk_fpu();
312 }
313 
314 void __init setup_arch(char **cmdline_p)
315 {
316 	/* This also populates @boot_command_line from /bootargs */
317 	machine_desc = setup_machine_fdt(__dtb_start);
318 	if (!machine_desc)
319 		panic("Embedded DT invalid\n");
320 
321 	/* Append any u-boot provided cmdline */
322 #ifdef CONFIG_CMDLINE_UBOOT
323 	/* Add a whitespace seperator between the 2 cmdlines */
324 	strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
325 	strlcat(boot_command_line, command_line, COMMAND_LINE_SIZE);
326 #endif
327 
328 	/* Save unparsed command line copy for /proc/cmdline */
329 	*cmdline_p = boot_command_line;
330 
331 	/* To force early parsing of things like mem=xxx */
332 	parse_early_param();
333 
334 	/* Platform/board specific: e.g. early console registration */
335 	if (machine_desc->init_early)
336 		machine_desc->init_early();
337 
338 	setup_processor();
339 
340 #ifdef CONFIG_SMP
341 	smp_init_cpus();
342 #endif
343 
344 	setup_arch_memory();
345 
346 	/* copy flat DT out of .init and then unflatten it */
347 	unflatten_and_copy_device_tree();
348 
349 	/* Can be issue if someone passes cmd line arg "ro"
350 	 * But that is unlikely so keeping it as it is
351 	 */
352 	root_mountflags &= ~MS_RDONLY;
353 
354 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
355 	conswitchp = &dummy_con;
356 #endif
357 
358 	arc_unwind_init();
359 	arc_unwind_setup();
360 }
361 
362 static int __init customize_machine(void)
363 {
364 	/* Add platform devices */
365 	if (machine_desc->init_machine)
366 		machine_desc->init_machine();
367 
368 	return 0;
369 }
370 arch_initcall(customize_machine);
371 
372 static int __init init_late_machine(void)
373 {
374 	if (machine_desc->init_late)
375 		machine_desc->init_late();
376 
377 	return 0;
378 }
379 late_initcall(init_late_machine);
380 /*
381  *  Get CPU information for use by the procfs.
382  */
383 
384 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
385 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
386 
387 static int show_cpuinfo(struct seq_file *m, void *v)
388 {
389 	char *str;
390 	int cpu_id = ptr_to_cpu(v);
391 
392 	str = (char *)__get_free_page(GFP_TEMPORARY);
393 	if (!str)
394 		goto done;
395 
396 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
397 
398 	seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n",
399 		   loops_per_jiffy / (500000 / HZ),
400 		   (loops_per_jiffy / (5000 / HZ)) % 100);
401 
402 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
403 
404 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
405 
406 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
407 
408 #ifdef CONFIG_SMP
409 	seq_printf(m, arc_platform_smp_cpuinfo());
410 #endif
411 
412 	free_page((unsigned long)str);
413 done:
414 	seq_printf(m, "\n\n");
415 
416 	return 0;
417 }
418 
419 static void *c_start(struct seq_file *m, loff_t *pos)
420 {
421 	/*
422 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
423 	 * However since NULL is also a valid cpu-id (0), we use a round-about
424 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
425 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
426 	 */
427 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
428 }
429 
430 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
431 {
432 	++*pos;
433 	return c_start(m, pos);
434 }
435 
436 static void c_stop(struct seq_file *m, void *v)
437 {
438 }
439 
440 const struct seq_operations cpuinfo_op = {
441 	.start	= c_start,
442 	.next	= c_next,
443 	.stop	= c_stop,
444 	.show	= show_cpuinfo
445 };
446 
447 static DEFINE_PER_CPU(struct cpu, cpu_topology);
448 
449 static int __init topology_init(void)
450 {
451 	int cpu;
452 
453 	for_each_present_cpu(cpu)
454 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
455 
456 	return 0;
457 }
458 
459 subsys_initcall(topology_init);
460