xref: /linux/arch/arc/kernel/setup.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732) 
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_arc_build_cfg_regs(void)
46 {
47 	struct bcr_perip uncached_space;
48 	struct bcr_generic bcr;
49 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
50 	unsigned long perip_space;
51 	FIX_PTR(cpu);
52 
53 	READ_BCR(AUX_IDENTITY, cpu->core);
54 	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
55 
56 	READ_BCR(ARC_REG_TIMERS_BCR, cpu->timers);
57 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
58 
59 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
60         if (uncached_space.ver < 3)
61 		perip_space = uncached_space.start << 24;
62 	else
63 		perip_space = read_aux_reg(AUX_NON_VOL) & 0xF0000000;
64 
65 	BUG_ON(perip_space != ARC_UNCACHED_ADDR_SPACE);
66 
67 	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
68 
69 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
70 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
71 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
72 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
73 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
74 
75 	/* Note that we read the CCM BCRs independent of kernel config
76 	 * This is to catch the cases where user doesn't know that
77 	 * CCMs are present in hardware build
78 	 */
79 	{
80 		struct bcr_iccm iccm;
81 		struct bcr_dccm dccm;
82 		struct bcr_dccm_base dccm_base;
83 		unsigned int bcr_32bit_val;
84 
85 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
86 		if (bcr_32bit_val) {
87 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
88 			cpu->iccm.base_addr = iccm.base << 16;
89 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
90 		}
91 
92 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
93 		if (bcr_32bit_val) {
94 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
95 			cpu->dccm.sz = 0x800 << (dccm.sz);
96 
97 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
98 			cpu->dccm.base_addr = dccm_base.addr << 8;
99 		}
100 	}
101 
102 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
103 
104 	read_decode_mmu_bcr();
105 	read_decode_cache_bcr();
106 
107 	if (is_isa_arcompact()) {
108 		struct bcr_fp_arcompact sp, dp;
109 		struct bcr_bpu_arcompact bpu;
110 
111 		READ_BCR(ARC_REG_FP_BCR, sp);
112 		READ_BCR(ARC_REG_DPFP_BCR, dp);
113 		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
114 		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
115 
116 		READ_BCR(ARC_REG_BPU_BCR, bpu);
117 		cpu->bpu.ver = bpu.ver;
118 		cpu->bpu.full = bpu.fam ? 1 : 0;
119 		if (bpu.ent) {
120 			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
121 			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
122 		}
123 	} else {
124 		struct bcr_fp_arcv2 spdp;
125 		struct bcr_bpu_arcv2 bpu;
126 
127 		READ_BCR(ARC_REG_FP_V2_BCR, spdp);
128 		cpu->extn.fpu_sp = spdp.sp ? 1 : 0;
129 		cpu->extn.fpu_dp = spdp.dp ? 1 : 0;
130 
131 		READ_BCR(ARC_REG_BPU_BCR, bpu);
132 		cpu->bpu.ver = bpu.ver;
133 		cpu->bpu.full = bpu.ft;
134 		cpu->bpu.num_cache = 256 << bpu.bce;
135 		cpu->bpu.num_pred = 2048 << bpu.pte;
136 	}
137 
138 	READ_BCR(ARC_REG_AP_BCR, bcr);
139 	cpu->extn.ap = bcr.ver ? 1 : 0;
140 
141 	READ_BCR(ARC_REG_SMART_BCR, bcr);
142 	cpu->extn.smart = bcr.ver ? 1 : 0;
143 
144 	READ_BCR(ARC_REG_RTT_BCR, bcr);
145 	cpu->extn.rtt = bcr.ver ? 1 : 0;
146 
147 	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
148 }
149 
150 static const struct cpuinfo_data arc_cpu_tbl[] = {
151 #ifdef CONFIG_ISA_ARCOMPACT
152 	{ {0x20, "ARC 600"      }, 0x2F},
153 	{ {0x30, "ARC 700"      }, 0x33},
154 	{ {0x34, "ARC 700 R4.10"}, 0x34},
155 	{ {0x35, "ARC 700 R4.11"}, 0x35},
156 #else
157 	{ {0x50, "ARC HS38 R2.0"}, 0x51},
158 	{ {0x52, "ARC HS38 R2.1"}, 0x52},
159 #endif
160 	{ {0x00, NULL		} }
161 };
162 
163 #define IS_AVAIL1(v, s)		((v) ? s : "")
164 #define IS_USED_RUN(v)		((v) ? "" : "(not used) ")
165 #define IS_USED_CFG(cfg)	IS_USED_RUN(IS_ENABLED(cfg))
166 #define IS_AVAIL2(v, s, cfg)	IS_AVAIL1(v, s), IS_AVAIL1(v, IS_USED_CFG(cfg))
167 
168 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
169 {
170 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
171 	struct bcr_identity *core = &cpu->core;
172 	const struct cpuinfo_data *tbl;
173 	char *isa_nm;
174 	int i, be, atomic;
175 	int n = 0;
176 
177 	FIX_PTR(cpu);
178 
179 	if (is_isa_arcompact()) {
180 		isa_nm = "ARCompact";
181 		be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
182 
183 		atomic = cpu->isa.atomic1;
184 		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
185 			atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
186 	} else {
187 		isa_nm = "ARCv2";
188 		be = cpu->isa.be;
189 		atomic = cpu->isa.atomic;
190 	}
191 
192 	n += scnprintf(buf + n, len - n,
193 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
194 		       core->family, core->cpu_id, core->chip_id);
195 
196 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
197 		if ((core->family >= tbl->info.id) &&
198 		    (core->family <= tbl->up_range)) {
199 			n += scnprintf(buf + n, len - n,
200 				       "processor [%d]\t: %s (%s ISA) %s\n",
201 				       cpu_id, tbl->info.str, isa_nm,
202 				       IS_AVAIL1(be, "[Big-Endian]"));
203 			break;
204 		}
205 	}
206 
207 	if (tbl->info.id == 0)
208 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
209 
210 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
211 		       (unsigned int)(arc_get_core_freq() / 1000000),
212 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
213 
214 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
215 		       IS_AVAIL1(cpu->timers.t0, "Timer0 "),
216 		       IS_AVAIL1(cpu->timers.t1, "Timer1 "),
217 		       IS_AVAIL2(cpu->timers.rtc, "64-bit RTC ",
218 				 CONFIG_ARC_HAS_RTC));
219 
220 	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
221 			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
222 			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
223 			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
224 
225 	if (i)
226 		n += scnprintf(buf + n, len - n, "\n\t\t: ");
227 
228 	if (cpu->extn_mpy.ver) {
229 		if (cpu->extn_mpy.ver <= 0x2) {	/* ARCompact */
230 			n += scnprintf(buf + n, len - n, "mpy ");
231 		} else {
232 			int opt = 2;	/* stock MPY/MPYH */
233 
234 			if (cpu->extn_mpy.dsp)	/* OPT 7-9 */
235 				opt = cpu->extn_mpy.dsp + 6;
236 
237 			n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
238 		}
239 		n += scnprintf(buf + n, len - n, "%s",
240 			       IS_USED_CFG(CONFIG_ARC_HAS_HW_MPY));
241 	}
242 
243 	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
244 		       IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
245 		       IS_AVAIL1(cpu->extn.norm, "norm "),
246 		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
247 		       IS_AVAIL1(cpu->extn.swap, "swap "),
248 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
249 		       IS_AVAIL1(cpu->extn.crc, "crc "),
250 		       IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
251 
252 	if (cpu->bpu.ver)
253 		n += scnprintf(buf + n, len - n,
254 			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
255 			      IS_AVAIL1(cpu->bpu.full, "full"),
256 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
257 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
258 
259 	return buf;
260 }
261 
262 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
263 {
264 	int n = 0;
265 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
266 
267 	FIX_PTR(cpu);
268 
269 	n += scnprintf(buf + n, len - n,
270 		       "Vector Table\t: %#x\nUncached Base\t: %#x\n",
271 		       cpu->vec_base, ARC_UNCACHED_ADDR_SPACE);
272 
273 	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
274 		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
275 			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
276 			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
277 
278 	if (cpu->extn.debug)
279 		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
280 			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
281 			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
282 			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
283 
284 	if (cpu->dccm.sz || cpu->iccm.sz)
285 		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
286 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
287 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
288 
289 	n += scnprintf(buf + n, len - n,
290 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
291 
292 	return buf;
293 }
294 
295 static void arc_chk_core_config(void)
296 {
297 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
298 	int fpu_enabled;
299 
300 	if (!cpu->timers.t0)
301 		panic("Timer0 is not present!\n");
302 
303 	if (!cpu->timers.t1)
304 		panic("Timer1 is not present!\n");
305 
306 	if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->timers.rtc)
307 		panic("RTC is not present\n");
308 
309 #ifdef CONFIG_ARC_HAS_DCCM
310 	/*
311 	 * DCCM can be arbit placed in hardware.
312 	 * Make sure it's placement/sz matches what Linux is built with
313 	 */
314 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
315 		panic("Linux built with incorrect DCCM Base address\n");
316 
317 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
318 		panic("Linux built with incorrect DCCM Size\n");
319 #endif
320 
321 #ifdef CONFIG_ARC_HAS_ICCM
322 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
323 		panic("Linux built with incorrect ICCM Size\n");
324 #endif
325 
326 	/*
327 	 * FP hardware/software config sanity
328 	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
329 	 * -If not, it will crash trying to save/restore the non-existant regs
330 	 *
331 	 * (only DPDP checked since SP has no arch visible regs)
332 	 */
333 	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
334 
335 	if (cpu->extn.fpu_dp && !fpu_enabled)
336 		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
337 	else if (!cpu->extn.fpu_dp && fpu_enabled)
338 		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
339 
340 	if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic &&
341 	    !IS_ENABLED(CONFIG_ARC_STAR_9000923308))
342 		panic("llock/scond livelock workaround missing\n");
343 }
344 
345 /*
346  * Initialize and setup the processor core
347  * This is called by all the CPUs thus should not do special case stuff
348  *    such as only for boot CPU etc
349  */
350 
351 void setup_processor(void)
352 {
353 	char str[512];
354 	int cpu_id = smp_processor_id();
355 
356 	read_arc_build_cfg_regs();
357 	arc_init_IRQ();
358 
359 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
360 
361 	arc_mmu_init();
362 	arc_cache_init();
363 
364 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
365 	printk(arc_platform_smp_cpuinfo());
366 
367 	arc_chk_core_config();
368 }
369 
370 static inline int is_kernel(unsigned long addr)
371 {
372 	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
373 		return 1;
374 	return 0;
375 }
376 
377 void __init setup_arch(char **cmdline_p)
378 {
379 #ifdef CONFIG_ARC_UBOOT_SUPPORT
380 	/* make sure that uboot passed pointer to cmdline/dtb is valid */
381 	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
382 		panic("Invalid uboot arg\n");
383 
384 	/* See if u-boot passed an external Device Tree blob */
385 	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
386 	if (!machine_desc)
387 #endif
388 	{
389 		/* No, so try the embedded one */
390 		machine_desc = setup_machine_fdt(__dtb_start);
391 		if (!machine_desc)
392 			panic("Embedded DT invalid\n");
393 
394 		/*
395 		 * If we are here, it is established that @uboot_arg didn't
396 		 * point to DT blob. Instead if u-boot says it is cmdline,
397 		 * Appent to embedded DT cmdline.
398 		 * setup_machine_fdt() would have populated @boot_command_line
399 		 */
400 		if (uboot_tag == 1) {
401 			/* Ensure a whitespace between the 2 cmdlines */
402 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
403 			strlcat(boot_command_line, uboot_arg,
404 				COMMAND_LINE_SIZE);
405 		}
406 	}
407 
408 	/* Save unparsed command line copy for /proc/cmdline */
409 	*cmdline_p = boot_command_line;
410 
411 	/* To force early parsing of things like mem=xxx */
412 	parse_early_param();
413 
414 	/* Platform/board specific: e.g. early console registration */
415 	if (machine_desc->init_early)
416 		machine_desc->init_early();
417 
418 	setup_processor();
419 	smp_init_cpus();
420 	setup_arch_memory();
421 
422 	/* copy flat DT out of .init and then unflatten it */
423 	unflatten_and_copy_device_tree();
424 
425 	/* Can be issue if someone passes cmd line arg "ro"
426 	 * But that is unlikely so keeping it as it is
427 	 */
428 	root_mountflags &= ~MS_RDONLY;
429 
430 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
431 	conswitchp = &dummy_con;
432 #endif
433 
434 	arc_unwind_init();
435 	arc_unwind_setup();
436 }
437 
438 static int __init customize_machine(void)
439 {
440 	of_clk_init(NULL);
441 	/*
442 	 * Traverses flattened DeviceTree - registering platform devices
443 	 * (if any) complete with their resources
444 	 */
445 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
446 
447 	if (machine_desc->init_machine)
448 		machine_desc->init_machine();
449 
450 	return 0;
451 }
452 arch_initcall(customize_machine);
453 
454 static int __init init_late_machine(void)
455 {
456 	if (machine_desc->init_late)
457 		machine_desc->init_late();
458 
459 	return 0;
460 }
461 late_initcall(init_late_machine);
462 /*
463  *  Get CPU information for use by the procfs.
464  */
465 
466 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
467 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
468 
469 static int show_cpuinfo(struct seq_file *m, void *v)
470 {
471 	char *str;
472 	int cpu_id = ptr_to_cpu(v);
473 
474 	if (!cpu_online(cpu_id)) {
475 		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
476 		goto done;
477 	}
478 
479 	str = (char *)__get_free_page(GFP_TEMPORARY);
480 	if (!str)
481 		goto done;
482 
483 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
484 
485 	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
486 		   loops_per_jiffy / (500000 / HZ),
487 		   (loops_per_jiffy / (5000 / HZ)) % 100);
488 
489 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
490 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
491 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
492 	seq_printf(m, arc_platform_smp_cpuinfo());
493 
494 	free_page((unsigned long)str);
495 done:
496 	seq_printf(m, "\n");
497 
498 	return 0;
499 }
500 
501 static void *c_start(struct seq_file *m, loff_t *pos)
502 {
503 	/*
504 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
505 	 * However since NULL is also a valid cpu-id (0), we use a round-about
506 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
507 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
508 	 */
509 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
510 }
511 
512 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
513 {
514 	++*pos;
515 	return c_start(m, pos);
516 }
517 
518 static void c_stop(struct seq_file *m, void *v)
519 {
520 }
521 
522 const struct seq_operations cpuinfo_op = {
523 	.start	= c_start,
524 	.next	= c_next,
525 	.stop	= c_stop,
526 	.show	= show_cpuinfo
527 };
528 
529 static DEFINE_PER_CPU(struct cpu, cpu_topology);
530 
531 static int __init topology_init(void)
532 {
533 	int cpu;
534 
535 	for_each_present_cpu(cpu)
536 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
537 
538 	return 0;
539 }
540 
541 subsys_initcall(topology_init);
542