xref: /openbmc/linux/arch/arc/kernel/setup.c (revision 4e1a33b1) 
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/clk-provider.h>
14 #include <linux/clocksource.h>
15 #include <linux/console.h>
16 #include <linux/module.h>
17 #include <linux/cpu.h>
18 #include <linux/of_fdt.h>
19 #include <linux/of.h>
20 #include <linux/cache.h>
21 #include <asm/sections.h>
22 #include <asm/arcregs.h>
23 #include <asm/tlb.h>
24 #include <asm/setup.h>
25 #include <asm/page.h>
26 #include <asm/irq.h>
27 #include <asm/unwind.h>
28 #include <asm/mach_desc.h>
29 #include <asm/smp.h>
30 
31 #define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
32 
33 unsigned int intr_to_DE_cnt;
34 
35 /* Part of U-boot ABI: see head.S */
36 int __initdata uboot_tag;
37 char __initdata *uboot_arg;
38 
39 const struct machine_desc *machine_desc;
40 
41 struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
42 
43 struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
44 
45 static const struct id_to_str arc_cpu_rel[] = {
46 #ifdef CONFIG_ISA_ARCOMPACT
47 	{ 0x34, "R4.10"},
48 	{ 0x35, "R4.11"},
49 #else
50 	{ 0x51, "R2.0" },
51 	{ 0x52, "R2.1" },
52 	{ 0x53, "R3.0" },
53 #endif
54 	{ 0x00, NULL   }
55 };
56 
57 static const struct id_to_str arc_cpu_nm[] = {
58 #ifdef CONFIG_ISA_ARCOMPACT
59 	{ 0x20, "ARC 600"   },
60 	{ 0x30, "ARC 770"   },  /* 750 identified seperately */
61 #else
62 	{ 0x40, "ARC EM"  },
63 	{ 0x50, "ARC HS38"  },
64 #endif
65 	{ 0x00, "Unknown"   }
66 };
67 
68 static void read_decode_ccm_bcr(struct cpuinfo_arc *cpu)
69 {
70 	if (is_isa_arcompact()) {
71 		struct bcr_iccm_arcompact iccm;
72 		struct bcr_dccm_arcompact dccm;
73 
74 		READ_BCR(ARC_REG_ICCM_BUILD, iccm);
75 		if (iccm.ver) {
76 			cpu->iccm.sz = 4096 << iccm.sz;	/* 8K to 512K */
77 			cpu->iccm.base_addr = iccm.base << 16;
78 		}
79 
80 		READ_BCR(ARC_REG_DCCM_BUILD, dccm);
81 		if (dccm.ver) {
82 			unsigned long base;
83 			cpu->dccm.sz = 2048 << dccm.sz;	/* 2K to 256K */
84 
85 			base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD);
86 			cpu->dccm.base_addr = base & ~0xF;
87 		}
88 	} else {
89 		struct bcr_iccm_arcv2 iccm;
90 		struct bcr_dccm_arcv2 dccm;
91 		unsigned long region;
92 
93 		READ_BCR(ARC_REG_ICCM_BUILD, iccm);
94 		if (iccm.ver) {
95 			cpu->iccm.sz = 256 << iccm.sz00;	/* 512B to 16M */
96 			if (iccm.sz00 == 0xF && iccm.sz01 > 0)
97 				cpu->iccm.sz <<= iccm.sz01;
98 
99 			region = read_aux_reg(ARC_REG_AUX_ICCM);
100 			cpu->iccm.base_addr = region & 0xF0000000;
101 		}
102 
103 		READ_BCR(ARC_REG_DCCM_BUILD, dccm);
104 		if (dccm.ver) {
105 			cpu->dccm.sz = 256 << dccm.sz0;
106 			if (dccm.sz0 == 0xF && dccm.sz1 > 0)
107 				cpu->dccm.sz <<= dccm.sz1;
108 
109 			region = read_aux_reg(ARC_REG_AUX_DCCM);
110 			cpu->dccm.base_addr = region & 0xF0000000;
111 		}
112 	}
113 }
114 
115 static void read_arc_build_cfg_regs(void)
116 {
117 	struct bcr_timer timer;
118 	struct bcr_generic bcr;
119 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
120 	const struct id_to_str *tbl;
121 
122 	FIX_PTR(cpu);
123 
124 	READ_BCR(AUX_IDENTITY, cpu->core);
125 	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
126 
127 	for (tbl = &arc_cpu_rel[0]; tbl->id != 0; tbl++) {
128 		if (cpu->core.family == tbl->id) {
129 			cpu->details = tbl->str;
130 			break;
131 		}
132 	}
133 
134 	for (tbl = &arc_cpu_nm[0]; tbl->id != 0; tbl++) {
135 		if ((cpu->core.family & 0xF0) == tbl->id)
136 			break;
137 	}
138 	cpu->name = tbl->str;
139 
140 	READ_BCR(ARC_REG_TIMERS_BCR, timer);
141 	cpu->extn.timer0 = timer.t0;
142 	cpu->extn.timer1 = timer.t1;
143 	cpu->extn.rtc = timer.rtc;
144 
145 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
146 
147 	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
148 
149 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
150 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
151 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
152 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
153 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
154 	cpu->extn.swape = (cpu->core.family >= 0x34) ? 1 :
155 				IS_ENABLED(CONFIG_ARC_HAS_SWAPE);
156 
157 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
158 
159 	/* Read CCM BCRs for boot reporting even if not enabled in Kconfig */
160 	read_decode_ccm_bcr(cpu);
161 
162 	read_decode_mmu_bcr();
163 	read_decode_cache_bcr();
164 
165 	if (is_isa_arcompact()) {
166 		struct bcr_fp_arcompact sp, dp;
167 		struct bcr_bpu_arcompact bpu;
168 
169 		READ_BCR(ARC_REG_FP_BCR, sp);
170 		READ_BCR(ARC_REG_DPFP_BCR, dp);
171 		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
172 		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
173 
174 		READ_BCR(ARC_REG_BPU_BCR, bpu);
175 		cpu->bpu.ver = bpu.ver;
176 		cpu->bpu.full = bpu.fam ? 1 : 0;
177 		if (bpu.ent) {
178 			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
179 			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
180 		}
181 	} else {
182 		struct bcr_fp_arcv2 spdp;
183 		struct bcr_bpu_arcv2 bpu;
184 
185 		READ_BCR(ARC_REG_FP_V2_BCR, spdp);
186 		cpu->extn.fpu_sp = spdp.sp ? 1 : 0;
187 		cpu->extn.fpu_dp = spdp.dp ? 1 : 0;
188 
189 		READ_BCR(ARC_REG_BPU_BCR, bpu);
190 		cpu->bpu.ver = bpu.ver;
191 		cpu->bpu.full = bpu.ft;
192 		cpu->bpu.num_cache = 256 << bpu.bce;
193 		cpu->bpu.num_pred = 2048 << bpu.pte;
194 	}
195 
196 	READ_BCR(ARC_REG_AP_BCR, bcr);
197 	cpu->extn.ap = bcr.ver ? 1 : 0;
198 
199 	READ_BCR(ARC_REG_SMART_BCR, bcr);
200 	cpu->extn.smart = bcr.ver ? 1 : 0;
201 
202 	READ_BCR(ARC_REG_RTT_BCR, bcr);
203 	cpu->extn.rtt = bcr.ver ? 1 : 0;
204 
205 	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
206 
207 	/* some hacks for lack of feature BCR info in old ARC700 cores */
208 	if (is_isa_arcompact()) {
209 		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
210 			cpu->isa.atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
211 		else
212 			cpu->isa.atomic = cpu->isa.atomic1;
213 
214 		cpu->isa.be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
215 
216 		 /* there's no direct way to distinguish 750 vs. 770 */
217 		if (unlikely(cpu->core.family < 0x34 || cpu->mmu.ver < 3))
218 			cpu->name = "ARC750";
219 	}
220 }
221 
222 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
223 {
224 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
225 	struct bcr_identity *core = &cpu->core;
226 	int i, n = 0;
227 
228 	FIX_PTR(cpu);
229 
230 	n += scnprintf(buf + n, len - n,
231 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
232 		       core->family, core->cpu_id, core->chip_id);
233 
234 	n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s\n",
235 		       cpu_id, cpu->name, cpu->details,
236 		       is_isa_arcompact() ? "ARCompact" : "ARCv2",
237 		       IS_AVAIL1(cpu->isa.be, "[Big-Endian]"));
238 
239 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s%s%s\nISA Extn\t: ",
240 		       IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
241 		       IS_AVAIL1(cpu->extn.timer1, "Timer1 "),
242 		       IS_AVAIL2(cpu->extn.rtc, "RTC [UP 64-bit] ", CONFIG_ARC_TIMERS_64BIT),
243 		       IS_AVAIL2(cpu->extn.gfrc, "GFRC [SMP 64-bit] ", CONFIG_ARC_TIMERS_64BIT));
244 
245 	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
246 			   IS_AVAIL2(cpu->isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
247 			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
248 			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
249 
250 	if (i)
251 		n += scnprintf(buf + n, len - n, "\n\t\t: ");
252 
253 	if (cpu->extn_mpy.ver) {
254 		if (cpu->extn_mpy.ver <= 0x2) {	/* ARCompact */
255 			n += scnprintf(buf + n, len - n, "mpy ");
256 		} else {
257 			int opt = 2;	/* stock MPY/MPYH */
258 
259 			if (cpu->extn_mpy.dsp)	/* OPT 7-9 */
260 				opt = cpu->extn_mpy.dsp + 6;
261 
262 			n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
263 		}
264 	}
265 
266 	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
267 		       IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
268 		       IS_AVAIL1(cpu->extn.norm, "norm "),
269 		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
270 		       IS_AVAIL1(cpu->extn.swap, "swap "),
271 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
272 		       IS_AVAIL1(cpu->extn.crc, "crc "),
273 		       IS_AVAIL2(cpu->extn.swape, "swape", CONFIG_ARC_HAS_SWAPE));
274 
275 	if (cpu->bpu.ver)
276 		n += scnprintf(buf + n, len - n,
277 			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
278 			      IS_AVAIL1(cpu->bpu.full, "full"),
279 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
280 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
281 
282 	return buf;
283 }
284 
285 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
286 {
287 	int n = 0;
288 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
289 
290 	FIX_PTR(cpu);
291 
292 	n += scnprintf(buf + n, len - n, "Vector Table\t: %#x\n", cpu->vec_base);
293 
294 	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
295 		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
296 			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
297 			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
298 
299 	if (cpu->extn.debug)
300 		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
301 			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
302 			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
303 			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
304 
305 	if (cpu->dccm.sz || cpu->iccm.sz)
306 		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
307 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
308 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
309 
310 	n += scnprintf(buf + n, len - n, "OS ABI [v%d]\t: %s\n",
311 			EF_ARC_OSABI_CURRENT >> 8,
312 			EF_ARC_OSABI_CURRENT == EF_ARC_OSABI_V3 ?
313 			"no-legacy-syscalls" : "64-bit data any register aligned");
314 
315 	return buf;
316 }
317 
318 static void arc_chk_core_config(void)
319 {
320 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
321 	int fpu_enabled;
322 
323 	if (!cpu->extn.timer0)
324 		panic("Timer0 is not present!\n");
325 
326 	if (!cpu->extn.timer1)
327 		panic("Timer1 is not present!\n");
328 
329 #ifdef CONFIG_ARC_HAS_DCCM
330 	/*
331 	 * DCCM can be arbit placed in hardware.
332 	 * Make sure it's placement/sz matches what Linux is built with
333 	 */
334 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
335 		panic("Linux built with incorrect DCCM Base address\n");
336 
337 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
338 		panic("Linux built with incorrect DCCM Size\n");
339 #endif
340 
341 #ifdef CONFIG_ARC_HAS_ICCM
342 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
343 		panic("Linux built with incorrect ICCM Size\n");
344 #endif
345 
346 	/*
347 	 * FP hardware/software config sanity
348 	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
349 	 * -If not, it will crash trying to save/restore the non-existant regs
350 	 *
351 	 * (only DPDP checked since SP has no arch visible regs)
352 	 */
353 	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
354 
355 	if (cpu->extn.fpu_dp && !fpu_enabled)
356 		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
357 	else if (!cpu->extn.fpu_dp && fpu_enabled)
358 		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
359 }
360 
361 /*
362  * Initialize and setup the processor core
363  * This is called by all the CPUs thus should not do special case stuff
364  *    such as only for boot CPU etc
365  */
366 
367 void setup_processor(void)
368 {
369 	char str[512];
370 	int cpu_id = smp_processor_id();
371 
372 	read_arc_build_cfg_regs();
373 	arc_init_IRQ();
374 
375 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
376 
377 	arc_mmu_init();
378 	arc_cache_init();
379 
380 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
381 	printk(arc_platform_smp_cpuinfo());
382 
383 	arc_chk_core_config();
384 }
385 
386 static inline int is_kernel(unsigned long addr)
387 {
388 	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
389 		return 1;
390 	return 0;
391 }
392 
393 void __init setup_arch(char **cmdline_p)
394 {
395 #ifdef CONFIG_ARC_UBOOT_SUPPORT
396 	/* make sure that uboot passed pointer to cmdline/dtb is valid */
397 	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
398 		panic("Invalid uboot arg\n");
399 
400 	/* See if u-boot passed an external Device Tree blob */
401 	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
402 	if (!machine_desc)
403 #endif
404 	{
405 		/* No, so try the embedded one */
406 		machine_desc = setup_machine_fdt(__dtb_start);
407 		if (!machine_desc)
408 			panic("Embedded DT invalid\n");
409 
410 		/*
411 		 * If we are here, it is established that @uboot_arg didn't
412 		 * point to DT blob. Instead if u-boot says it is cmdline,
413 		 * append to embedded DT cmdline.
414 		 * setup_machine_fdt() would have populated @boot_command_line
415 		 */
416 		if (uboot_tag == 1) {
417 			/* Ensure a whitespace between the 2 cmdlines */
418 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
419 			strlcat(boot_command_line, uboot_arg,
420 				COMMAND_LINE_SIZE);
421 		}
422 	}
423 
424 	/* Save unparsed command line copy for /proc/cmdline */
425 	*cmdline_p = boot_command_line;
426 
427 	/* To force early parsing of things like mem=xxx */
428 	parse_early_param();
429 
430 	/* Platform/board specific: e.g. early console registration */
431 	if (machine_desc->init_early)
432 		machine_desc->init_early();
433 
434 	smp_init_cpus();
435 
436 	setup_processor();
437 	setup_arch_memory();
438 
439 	/* copy flat DT out of .init and then unflatten it */
440 	unflatten_and_copy_device_tree();
441 
442 	/* Can be issue if someone passes cmd line arg "ro"
443 	 * But that is unlikely so keeping it as it is
444 	 */
445 	root_mountflags &= ~MS_RDONLY;
446 
447 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
448 	conswitchp = &dummy_con;
449 #endif
450 
451 	arc_unwind_init();
452 }
453 
454 /*
455  * Called from start_kernel() - boot CPU only
456  */
457 void __init time_init(void)
458 {
459 	of_clk_init(NULL);
460 	clocksource_probe();
461 }
462 
463 static int __init customize_machine(void)
464 {
465 	if (machine_desc->init_machine)
466 		machine_desc->init_machine();
467 
468 	return 0;
469 }
470 arch_initcall(customize_machine);
471 
472 static int __init init_late_machine(void)
473 {
474 	if (machine_desc->init_late)
475 		machine_desc->init_late();
476 
477 	return 0;
478 }
479 late_initcall(init_late_machine);
480 /*
481  *  Get CPU information for use by the procfs.
482  */
483 
484 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
485 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
486 
487 static int show_cpuinfo(struct seq_file *m, void *v)
488 {
489 	char *str;
490 	int cpu_id = ptr_to_cpu(v);
491 	struct device_node *core_clk = of_find_node_by_name(NULL, "core_clk");
492 	u32 freq = 0;
493 
494 	if (!cpu_online(cpu_id)) {
495 		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
496 		goto done;
497 	}
498 
499 	str = (char *)__get_free_page(GFP_TEMPORARY);
500 	if (!str)
501 		goto done;
502 
503 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
504 
505 	of_property_read_u32(core_clk, "clock-frequency", &freq);
506 	if (freq)
507 		seq_printf(m, "CPU speed\t: %u.%02u Mhz\n",
508 			   freq / 1000000, (freq / 10000) % 100);
509 
510 	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
511 		   loops_per_jiffy / (500000 / HZ),
512 		   (loops_per_jiffy / (5000 / HZ)) % 100);
513 
514 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
515 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
516 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
517 	seq_printf(m, arc_platform_smp_cpuinfo());
518 
519 	free_page((unsigned long)str);
520 done:
521 	seq_printf(m, "\n");
522 
523 	return 0;
524 }
525 
526 static void *c_start(struct seq_file *m, loff_t *pos)
527 {
528 	/*
529 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
530 	 * However since NULL is also a valid cpu-id (0), we use a round-about
531 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
532 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
533 	 */
534 	return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
535 }
536 
537 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
538 {
539 	++*pos;
540 	return c_start(m, pos);
541 }
542 
543 static void c_stop(struct seq_file *m, void *v)
544 {
545 }
546 
547 const struct seq_operations cpuinfo_op = {
548 	.start	= c_start,
549 	.next	= c_next,
550 	.stop	= c_stop,
551 	.show	= show_cpuinfo
552 };
553 
554 static DEFINE_PER_CPU(struct cpu, cpu_topology);
555 
556 static int __init topology_init(void)
557 {
558 	int cpu;
559 
560 	for_each_present_cpu(cpu)
561 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
562 
563 	return 0;
564 }
565 
566 subsys_initcall(topology_init);
567