xref: /openbmc/linux/arch/arc/kernel/setup.c (revision 2596e07a)
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/clk-provider.h>
17 #include <linux/of_fdt.h>
18 #include <linux/of_platform.h>
19 #include <linux/cache.h>
20 #include <asm/sections.h>
21 #include <asm/arcregs.h>
22 #include <asm/tlb.h>
23 #include <asm/setup.h>
24 #include <asm/page.h>
25 #include <asm/irq.h>
26 #include <asm/unwind.h>
27 #include <asm/clk.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 void read_decode_ccm_bcr(struct cpuinfo_arc *cpu)
46 {
47 	if (is_isa_arcompact()) {
48 		struct bcr_iccm_arcompact iccm;
49 		struct bcr_dccm_arcompact dccm;
50 
51 		READ_BCR(ARC_REG_ICCM_BUILD, iccm);
52 		if (iccm.ver) {
53 			cpu->iccm.sz = 4096 << iccm.sz;	/* 8K to 512K */
54 			cpu->iccm.base_addr = iccm.base << 16;
55 		}
56 
57 		READ_BCR(ARC_REG_DCCM_BUILD, dccm);
58 		if (dccm.ver) {
59 			unsigned long base;
60 			cpu->dccm.sz = 2048 << dccm.sz;	/* 2K to 256K */
61 
62 			base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD);
63 			cpu->dccm.base_addr = base & ~0xF;
64 		}
65 	} else {
66 		struct bcr_iccm_arcv2 iccm;
67 		struct bcr_dccm_arcv2 dccm;
68 		unsigned long region;
69 
70 		READ_BCR(ARC_REG_ICCM_BUILD, iccm);
71 		if (iccm.ver) {
72 			cpu->iccm.sz = 256 << iccm.sz00;	/* 512B to 16M */
73 			if (iccm.sz00 == 0xF && iccm.sz01 > 0)
74 				cpu->iccm.sz <<= iccm.sz01;
75 
76 			region = read_aux_reg(ARC_REG_AUX_ICCM);
77 			cpu->iccm.base_addr = region & 0xF0000000;
78 		}
79 
80 		READ_BCR(ARC_REG_DCCM_BUILD, dccm);
81 		if (dccm.ver) {
82 			cpu->dccm.sz = 256 << dccm.sz0;
83 			if (dccm.sz0 == 0xF && dccm.sz1 > 0)
84 				cpu->dccm.sz <<= dccm.sz1;
85 
86 			region = read_aux_reg(ARC_REG_AUX_DCCM);
87 			cpu->dccm.base_addr = region & 0xF0000000;
88 		}
89 	}
90 }
91 
92 static void read_arc_build_cfg_regs(void)
93 {
94 	struct bcr_perip uncached_space;
95 	struct bcr_timer timer;
96 	struct bcr_generic bcr;
97 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
98 	unsigned long perip_space;
99 	FIX_PTR(cpu);
100 
101 	READ_BCR(AUX_IDENTITY, cpu->core);
102 	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
103 
104 	READ_BCR(ARC_REG_TIMERS_BCR, timer);
105 	cpu->extn.timer0 = timer.t0;
106 	cpu->extn.timer1 = timer.t1;
107 	cpu->extn.rtc = timer.rtc;
108 
109 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
110 
111 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
112         if (uncached_space.ver < 3)
113 		perip_space = uncached_space.start << 24;
114 	else
115 		perip_space = read_aux_reg(AUX_NON_VOL) & 0xF0000000;
116 
117 	BUG_ON(perip_space != ARC_UNCACHED_ADDR_SPACE);
118 
119 	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
120 
121 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
122 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
123 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
124 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
125 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
126 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
127 
128 	/* Read CCM BCRs for boot reporting even if not enabled in Kconfig */
129 	read_decode_ccm_bcr(cpu);
130 
131 	read_decode_mmu_bcr();
132 	read_decode_cache_bcr();
133 
134 	if (is_isa_arcompact()) {
135 		struct bcr_fp_arcompact sp, dp;
136 		struct bcr_bpu_arcompact bpu;
137 
138 		READ_BCR(ARC_REG_FP_BCR, sp);
139 		READ_BCR(ARC_REG_DPFP_BCR, dp);
140 		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
141 		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
142 
143 		READ_BCR(ARC_REG_BPU_BCR, bpu);
144 		cpu->bpu.ver = bpu.ver;
145 		cpu->bpu.full = bpu.fam ? 1 : 0;
146 		if (bpu.ent) {
147 			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
148 			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
149 		}
150 	} else {
151 		struct bcr_fp_arcv2 spdp;
152 		struct bcr_bpu_arcv2 bpu;
153 
154 		READ_BCR(ARC_REG_FP_V2_BCR, spdp);
155 		cpu->extn.fpu_sp = spdp.sp ? 1 : 0;
156 		cpu->extn.fpu_dp = spdp.dp ? 1 : 0;
157 
158 		READ_BCR(ARC_REG_BPU_BCR, bpu);
159 		cpu->bpu.ver = bpu.ver;
160 		cpu->bpu.full = bpu.ft;
161 		cpu->bpu.num_cache = 256 << bpu.bce;
162 		cpu->bpu.num_pred = 2048 << bpu.pte;
163 	}
164 
165 	READ_BCR(ARC_REG_AP_BCR, bcr);
166 	cpu->extn.ap = bcr.ver ? 1 : 0;
167 
168 	READ_BCR(ARC_REG_SMART_BCR, bcr);
169 	cpu->extn.smart = bcr.ver ? 1 : 0;
170 
171 	READ_BCR(ARC_REG_RTT_BCR, bcr);
172 	cpu->extn.rtt = bcr.ver ? 1 : 0;
173 
174 	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
175 }
176 
177 static const struct cpuinfo_data arc_cpu_tbl[] = {
178 #ifdef CONFIG_ISA_ARCOMPACT
179 	{ {0x20, "ARC 600"      }, 0x2F},
180 	{ {0x30, "ARC 700"      }, 0x33},
181 	{ {0x34, "ARC 700 R4.10"}, 0x34},
182 	{ {0x35, "ARC 700 R4.11"}, 0x35},
183 #else
184 	{ {0x50, "ARC HS38 R2.0"}, 0x51},
185 	{ {0x52, "ARC HS38 R2.1"}, 0x52},
186 #endif
187 	{ {0x00, NULL		} }
188 };
189 
190 
191 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
192 {
193 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
194 	struct bcr_identity *core = &cpu->core;
195 	const struct cpuinfo_data *tbl;
196 	char *isa_nm;
197 	int i, be, atomic;
198 	int n = 0;
199 
200 	FIX_PTR(cpu);
201 
202 	if (is_isa_arcompact()) {
203 		isa_nm = "ARCompact";
204 		be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
205 
206 		atomic = cpu->isa.atomic1;
207 		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
208 			atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
209 	} else {
210 		isa_nm = "ARCv2";
211 		be = cpu->isa.be;
212 		atomic = cpu->isa.atomic;
213 	}
214 
215 	n += scnprintf(buf + n, len - n,
216 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
217 		       core->family, core->cpu_id, core->chip_id);
218 
219 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
220 		if ((core->family >= tbl->info.id) &&
221 		    (core->family <= tbl->up_range)) {
222 			n += scnprintf(buf + n, len - n,
223 				       "processor [%d]\t: %s (%s ISA) %s\n",
224 				       cpu_id, tbl->info.str, isa_nm,
225 				       IS_AVAIL1(be, "[Big-Endian]"));
226 			break;
227 		}
228 	}
229 
230 	if (tbl->info.id == 0)
231 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
232 
233 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
234 		       (unsigned int)(arc_get_core_freq() / 1000000),
235 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
236 
237 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
238 		       IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
239 		       IS_AVAIL1(cpu->extn.timer1, "Timer1 "),
240 		       IS_AVAIL2(cpu->extn.rtc, "Local-64-bit-Ctr ",
241 				 CONFIG_ARC_HAS_RTC));
242 
243 	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
244 			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
245 			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
246 			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
247 
248 	if (i)
249 		n += scnprintf(buf + n, len - n, "\n\t\t: ");
250 
251 	if (cpu->extn_mpy.ver) {
252 		if (cpu->extn_mpy.ver <= 0x2) {	/* ARCompact */
253 			n += scnprintf(buf + n, len - n, "mpy ");
254 		} else {
255 			int opt = 2;	/* stock MPY/MPYH */
256 
257 			if (cpu->extn_mpy.dsp)	/* OPT 7-9 */
258 				opt = cpu->extn_mpy.dsp + 6;
259 
260 			n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
261 		}
262 	}
263 
264 	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
265 		       IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
266 		       IS_AVAIL1(cpu->extn.norm, "norm "),
267 		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
268 		       IS_AVAIL1(cpu->extn.swap, "swap "),
269 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
270 		       IS_AVAIL1(cpu->extn.crc, "crc "),
271 		       IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
272 
273 	if (cpu->bpu.ver)
274 		n += scnprintf(buf + n, len - n,
275 			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
276 			      IS_AVAIL1(cpu->bpu.full, "full"),
277 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
278 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
279 
280 	return buf;
281 }
282 
283 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
284 {
285 	int n = 0;
286 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
287 
288 	FIX_PTR(cpu);
289 
290 	n += scnprintf(buf + n, len - n,
291 		       "Vector Table\t: %#x\nUncached Base\t: %#x\n",
292 		       cpu->vec_base, ARC_UNCACHED_ADDR_SPACE);
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,
311 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
312 
313 	return buf;
314 }
315 
316 static void arc_chk_core_config(void)
317 {
318 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
319 	int fpu_enabled;
320 
321 	if (!cpu->extn.timer0)
322 		panic("Timer0 is not present!\n");
323 
324 	if (!cpu->extn.timer1)
325 		panic("Timer1 is not present!\n");
326 
327 	if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->extn.rtc)
328 		panic("RTC is not present\n");
329 
330 #ifdef CONFIG_ARC_HAS_DCCM
331 	/*
332 	 * DCCM can be arbit placed in hardware.
333 	 * Make sure it's placement/sz matches what Linux is built with
334 	 */
335 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
336 		panic("Linux built with incorrect DCCM Base address\n");
337 
338 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
339 		panic("Linux built with incorrect DCCM Size\n");
340 #endif
341 
342 #ifdef CONFIG_ARC_HAS_ICCM
343 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
344 		panic("Linux built with incorrect ICCM Size\n");
345 #endif
346 
347 	/*
348 	 * FP hardware/software config sanity
349 	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
350 	 * -If not, it will crash trying to save/restore the non-existant regs
351 	 *
352 	 * (only DPDP checked since SP has no arch visible regs)
353 	 */
354 	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
355 
356 	if (cpu->extn.fpu_dp && !fpu_enabled)
357 		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
358 	else if (!cpu->extn.fpu_dp && fpu_enabled)
359 		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
360 
361 	if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic &&
362 	    IS_ENABLED(CONFIG_ARC_HAS_LLSC) &&
363 	    !IS_ENABLED(CONFIG_ARC_STAR_9000923308))
364 		panic("llock/scond livelock workaround missing\n");
365 }
366 
367 /*
368  * Initialize and setup the processor core
369  * This is called by all the CPUs thus should not do special case stuff
370  *    such as only for boot CPU etc
371  */
372 
373 void setup_processor(void)
374 {
375 	char str[512];
376 	int cpu_id = smp_processor_id();
377 
378 	read_arc_build_cfg_regs();
379 	arc_init_IRQ();
380 
381 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
382 
383 	arc_mmu_init();
384 	arc_cache_init();
385 
386 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
387 	printk(arc_platform_smp_cpuinfo());
388 
389 	arc_chk_core_config();
390 }
391 
392 static inline int is_kernel(unsigned long addr)
393 {
394 	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
395 		return 1;
396 	return 0;
397 }
398 
399 void __init setup_arch(char **cmdline_p)
400 {
401 #ifdef CONFIG_ARC_UBOOT_SUPPORT
402 	/* make sure that uboot passed pointer to cmdline/dtb is valid */
403 	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
404 		panic("Invalid uboot arg\n");
405 
406 	/* See if u-boot passed an external Device Tree blob */
407 	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
408 	if (!machine_desc)
409 #endif
410 	{
411 		/* No, so try the embedded one */
412 		machine_desc = setup_machine_fdt(__dtb_start);
413 		if (!machine_desc)
414 			panic("Embedded DT invalid\n");
415 
416 		/*
417 		 * If we are here, it is established that @uboot_arg didn't
418 		 * point to DT blob. Instead if u-boot says it is cmdline,
419 		 * Appent to embedded DT cmdline.
420 		 * setup_machine_fdt() would have populated @boot_command_line
421 		 */
422 		if (uboot_tag == 1) {
423 			/* Ensure a whitespace between the 2 cmdlines */
424 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
425 			strlcat(boot_command_line, uboot_arg,
426 				COMMAND_LINE_SIZE);
427 		}
428 	}
429 
430 	/* Save unparsed command line copy for /proc/cmdline */
431 	*cmdline_p = boot_command_line;
432 
433 	/* To force early parsing of things like mem=xxx */
434 	parse_early_param();
435 
436 	/* Platform/board specific: e.g. early console registration */
437 	if (machine_desc->init_early)
438 		machine_desc->init_early();
439 
440 	smp_init_cpus();
441 
442 	setup_processor();
443 	setup_arch_memory();
444 
445 	/* copy flat DT out of .init and then unflatten it */
446 	unflatten_and_copy_device_tree();
447 
448 	/* Can be issue if someone passes cmd line arg "ro"
449 	 * But that is unlikely so keeping it as it is
450 	 */
451 	root_mountflags &= ~MS_RDONLY;
452 
453 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
454 	conswitchp = &dummy_con;
455 #endif
456 
457 	arc_unwind_init();
458 }
459 
460 static int __init customize_machine(void)
461 {
462 	of_clk_init(NULL);
463 	/*
464 	 * Traverses flattened DeviceTree - registering platform devices
465 	 * (if any) complete with their resources
466 	 */
467 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
468 
469 	if (machine_desc->init_machine)
470 		machine_desc->init_machine();
471 
472 	return 0;
473 }
474 arch_initcall(customize_machine);
475 
476 static int __init init_late_machine(void)
477 {
478 	if (machine_desc->init_late)
479 		machine_desc->init_late();
480 
481 	return 0;
482 }
483 late_initcall(init_late_machine);
484 /*
485  *  Get CPU information for use by the procfs.
486  */
487 
488 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
489 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
490 
491 static int show_cpuinfo(struct seq_file *m, void *v)
492 {
493 	char *str;
494 	int cpu_id = ptr_to_cpu(v);
495 
496 	if (!cpu_online(cpu_id)) {
497 		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
498 		goto done;
499 	}
500 
501 	str = (char *)__get_free_page(GFP_TEMPORARY);
502 	if (!str)
503 		goto done;
504 
505 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
506 
507 	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
508 		   loops_per_jiffy / (500000 / HZ),
509 		   (loops_per_jiffy / (5000 / HZ)) % 100);
510 
511 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
512 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
513 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
514 	seq_printf(m, arc_platform_smp_cpuinfo());
515 
516 	free_page((unsigned long)str);
517 done:
518 	seq_printf(m, "\n");
519 
520 	return 0;
521 }
522 
523 static void *c_start(struct seq_file *m, loff_t *pos)
524 {
525 	/*
526 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
527 	 * However since NULL is also a valid cpu-id (0), we use a round-about
528 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
529 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
530 	 */
531 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
532 }
533 
534 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
535 {
536 	++*pos;
537 	return c_start(m, pos);
538 }
539 
540 static void c_stop(struct seq_file *m, void *v)
541 {
542 }
543 
544 const struct seq_operations cpuinfo_op = {
545 	.start	= c_start,
546 	.next	= c_next,
547 	.stop	= c_stop,
548 	.show	= show_cpuinfo
549 };
550 
551 static DEFINE_PER_CPU(struct cpu, cpu_topology);
552 
553 static int __init topology_init(void)
554 {
555 	int cpu;
556 
557 	for_each_present_cpu(cpu)
558 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
559 
560 	return 0;
561 }
562 
563 subsys_initcall(topology_init);
564