xref: /openbmc/linux/arch/arc/kernel/setup.c (revision 179dd8c0)
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 	FIX_PTR(cpu);
51 
52 	READ_BCR(AUX_IDENTITY, cpu->core);
53 	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
54 
55 	READ_BCR(ARC_REG_TIMERS_BCR, cpu->timers);
56 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
57 
58 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
59 	BUG_ON((uncached_space.start << 24) != ARC_UNCACHED_ADDR_SPACE);
60 
61 	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
62 
63 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
64 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
65 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
66 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
67 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
68 
69 	/* Note that we read the CCM BCRs independent of kernel config
70 	 * This is to catch the cases where user doesn't know that
71 	 * CCMs are present in hardware build
72 	 */
73 	{
74 		struct bcr_iccm iccm;
75 		struct bcr_dccm dccm;
76 		struct bcr_dccm_base dccm_base;
77 		unsigned int bcr_32bit_val;
78 
79 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
80 		if (bcr_32bit_val) {
81 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
82 			cpu->iccm.base_addr = iccm.base << 16;
83 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
84 		}
85 
86 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
87 		if (bcr_32bit_val) {
88 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
89 			cpu->dccm.sz = 0x800 << (dccm.sz);
90 
91 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
92 			cpu->dccm.base_addr = dccm_base.addr << 8;
93 		}
94 	}
95 
96 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
97 
98 	read_decode_mmu_bcr();
99 	read_decode_cache_bcr();
100 
101 	if (is_isa_arcompact()) {
102 		struct bcr_fp_arcompact sp, dp;
103 		struct bcr_bpu_arcompact bpu;
104 
105 		READ_BCR(ARC_REG_FP_BCR, sp);
106 		READ_BCR(ARC_REG_DPFP_BCR, dp);
107 		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
108 		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
109 
110 		READ_BCR(ARC_REG_BPU_BCR, bpu);
111 		cpu->bpu.ver = bpu.ver;
112 		cpu->bpu.full = bpu.fam ? 1 : 0;
113 		if (bpu.ent) {
114 			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
115 			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
116 		}
117 	} else {
118 		struct bcr_fp_arcv2 spdp;
119 		struct bcr_bpu_arcv2 bpu;
120 
121 		READ_BCR(ARC_REG_FP_V2_BCR, spdp);
122 		cpu->extn.fpu_sp = spdp.sp ? 1 : 0;
123 		cpu->extn.fpu_dp = spdp.dp ? 1 : 0;
124 
125 		READ_BCR(ARC_REG_BPU_BCR, bpu);
126 		cpu->bpu.ver = bpu.ver;
127 		cpu->bpu.full = bpu.ft;
128 		cpu->bpu.num_cache = 256 << bpu.bce;
129 		cpu->bpu.num_pred = 2048 << bpu.pte;
130 	}
131 
132 	READ_BCR(ARC_REG_AP_BCR, bcr);
133 	cpu->extn.ap = bcr.ver ? 1 : 0;
134 
135 	READ_BCR(ARC_REG_SMART_BCR, bcr);
136 	cpu->extn.smart = bcr.ver ? 1 : 0;
137 
138 	READ_BCR(ARC_REG_RTT_BCR, bcr);
139 	cpu->extn.rtt = bcr.ver ? 1 : 0;
140 
141 	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
142 }
143 
144 static const struct cpuinfo_data arc_cpu_tbl[] = {
145 	{ {0x20, "ARC 600"      }, 0x2F},
146 	{ {0x30, "ARC 700"      }, 0x33},
147 	{ {0x34, "ARC 700 R4.10"}, 0x34},
148 	{ {0x35, "ARC 700 R4.11"}, 0x35},
149 	{ {0x50, "ARC HS38"	}, 0x51},
150 	{ {0x00, NULL		} }
151 };
152 
153 #define IS_AVAIL1(v, str)	((v) ? str : "")
154 #define IS_USED(cfg)		(IS_ENABLED(cfg) ? "" : "(not used) ")
155 #define IS_AVAIL2(v, str, cfg)  IS_AVAIL1(v, str), IS_AVAIL1(v, IS_USED(cfg))
156 
157 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
158 {
159 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
160 	struct bcr_identity *core = &cpu->core;
161 	const struct cpuinfo_data *tbl;
162 	char *isa_nm;
163 	int i, be, atomic;
164 	int n = 0;
165 
166 	FIX_PTR(cpu);
167 
168 	if (is_isa_arcompact()) {
169 		isa_nm = "ARCompact";
170 		be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
171 
172 		atomic = cpu->isa.atomic1;
173 		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
174 			atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
175 	} else {
176 		isa_nm = "ARCv2";
177 		be = cpu->isa.be;
178 		atomic = cpu->isa.atomic;
179 	}
180 
181 	n += scnprintf(buf + n, len - n,
182 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
183 		       core->family, core->cpu_id, core->chip_id);
184 
185 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
186 		if ((core->family >= tbl->info.id) &&
187 		    (core->family <= tbl->up_range)) {
188 			n += scnprintf(buf + n, len - n,
189 				       "processor [%d]\t: %s (%s ISA) %s\n",
190 				       cpu_id, tbl->info.str, isa_nm,
191 				       IS_AVAIL1(be, "[Big-Endian]"));
192 			break;
193 		}
194 	}
195 
196 	if (tbl->info.id == 0)
197 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
198 
199 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
200 		       (unsigned int)(arc_get_core_freq() / 1000000),
201 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
202 
203 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
204 		       IS_AVAIL1(cpu->timers.t0, "Timer0 "),
205 		       IS_AVAIL1(cpu->timers.t1, "Timer1 "),
206 		       IS_AVAIL2(cpu->timers.rtc, "64-bit RTC ",
207 				 CONFIG_ARC_HAS_RTC));
208 
209 	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
210 			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
211 			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
212 			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
213 
214 	if (i)
215 		n += scnprintf(buf + n, len - n, "\n\t\t: ");
216 
217 	if (cpu->extn_mpy.ver) {
218 		if (cpu->extn_mpy.ver <= 0x2) {	/* ARCompact */
219 			n += scnprintf(buf + n, len - n, "mpy ");
220 		} else {
221 			int opt = 2;	/* stock MPY/MPYH */
222 
223 			if (cpu->extn_mpy.dsp)	/* OPT 7-9 */
224 				opt = cpu->extn_mpy.dsp + 6;
225 
226 			n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
227 		}
228 		n += scnprintf(buf + n, len - n, "%s",
229 			       IS_USED(CONFIG_ARC_HAS_HW_MPY));
230 	}
231 
232 	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
233 		       IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
234 		       IS_AVAIL1(cpu->extn.norm, "norm "),
235 		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
236 		       IS_AVAIL1(cpu->extn.swap, "swap "),
237 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
238 		       IS_AVAIL1(cpu->extn.crc, "crc "),
239 		       IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
240 
241 	if (cpu->bpu.ver)
242 		n += scnprintf(buf + n, len - n,
243 			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
244 			      IS_AVAIL1(cpu->bpu.full, "full"),
245 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
246 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
247 
248 	return buf;
249 }
250 
251 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
252 {
253 	int n = 0;
254 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
255 
256 	FIX_PTR(cpu);
257 
258 	n += scnprintf(buf + n, len - n,
259 		       "Vector Table\t: %#x\nUncached Base\t: %#x\n",
260 		       cpu->vec_base, ARC_UNCACHED_ADDR_SPACE);
261 
262 	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
263 		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
264 			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
265 			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
266 
267 	if (cpu->extn.debug)
268 		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
269 			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
270 			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
271 			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
272 
273 	if (cpu->dccm.sz || cpu->iccm.sz)
274 		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
275 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
276 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
277 
278 	n += scnprintf(buf + n, len - n,
279 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
280 
281 	return buf;
282 }
283 
284 static void arc_chk_core_config(void)
285 {
286 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
287 	int fpu_enabled;
288 
289 	if (!cpu->timers.t0)
290 		panic("Timer0 is not present!\n");
291 
292 	if (!cpu->timers.t1)
293 		panic("Timer1 is not present!\n");
294 
295 	if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->timers.rtc)
296 		panic("RTC is not present\n");
297 
298 #ifdef CONFIG_ARC_HAS_DCCM
299 	/*
300 	 * DCCM can be arbit placed in hardware.
301 	 * Make sure it's placement/sz matches what Linux is built with
302 	 */
303 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
304 		panic("Linux built with incorrect DCCM Base address\n");
305 
306 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
307 		panic("Linux built with incorrect DCCM Size\n");
308 #endif
309 
310 #ifdef CONFIG_ARC_HAS_ICCM
311 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
312 		panic("Linux built with incorrect ICCM Size\n");
313 #endif
314 
315 	/*
316 	 * FP hardware/software config sanity
317 	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
318 	 * -If not, it will crash trying to save/restore the non-existant regs
319 	 *
320 	 * (only DPDP checked since SP has no arch visible regs)
321 	 */
322 	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
323 
324 	if (cpu->extn.fpu_dp && !fpu_enabled)
325 		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
326 	else if (!cpu->extn.fpu_dp && fpu_enabled)
327 		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
328 }
329 
330 /*
331  * Initialize and setup the processor core
332  * This is called by all the CPUs thus should not do special case stuff
333  *    such as only for boot CPU etc
334  */
335 
336 void setup_processor(void)
337 {
338 	char str[512];
339 	int cpu_id = smp_processor_id();
340 
341 	read_arc_build_cfg_regs();
342 	arc_init_IRQ();
343 
344 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
345 
346 	arc_mmu_init();
347 	arc_cache_init();
348 
349 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
350 	printk(arc_platform_smp_cpuinfo());
351 
352 	arc_chk_core_config();
353 }
354 
355 static inline int is_kernel(unsigned long addr)
356 {
357 	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
358 		return 1;
359 	return 0;
360 }
361 
362 void __init setup_arch(char **cmdline_p)
363 {
364 #ifdef CONFIG_ARC_UBOOT_SUPPORT
365 	/* make sure that uboot passed pointer to cmdline/dtb is valid */
366 	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
367 		panic("Invalid uboot arg\n");
368 
369 	/* See if u-boot passed an external Device Tree blob */
370 	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
371 	if (!machine_desc)
372 #endif
373 	{
374 		/* No, so try the embedded one */
375 		machine_desc = setup_machine_fdt(__dtb_start);
376 		if (!machine_desc)
377 			panic("Embedded DT invalid\n");
378 
379 		/*
380 		 * If we are here, it is established that @uboot_arg didn't
381 		 * point to DT blob. Instead if u-boot says it is cmdline,
382 		 * Appent to embedded DT cmdline.
383 		 * setup_machine_fdt() would have populated @boot_command_line
384 		 */
385 		if (uboot_tag == 1) {
386 			/* Ensure a whitespace between the 2 cmdlines */
387 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
388 			strlcat(boot_command_line, uboot_arg,
389 				COMMAND_LINE_SIZE);
390 		}
391 	}
392 
393 	/* Save unparsed command line copy for /proc/cmdline */
394 	*cmdline_p = boot_command_line;
395 
396 	/* To force early parsing of things like mem=xxx */
397 	parse_early_param();
398 
399 	/* Platform/board specific: e.g. early console registration */
400 	if (machine_desc->init_early)
401 		machine_desc->init_early();
402 
403 	setup_processor();
404 	smp_init_cpus();
405 	setup_arch_memory();
406 
407 	/* copy flat DT out of .init and then unflatten it */
408 	unflatten_and_copy_device_tree();
409 
410 	/* Can be issue if someone passes cmd line arg "ro"
411 	 * But that is unlikely so keeping it as it is
412 	 */
413 	root_mountflags &= ~MS_RDONLY;
414 
415 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
416 	conswitchp = &dummy_con;
417 #endif
418 
419 	arc_unwind_init();
420 	arc_unwind_setup();
421 }
422 
423 static int __init customize_machine(void)
424 {
425 	of_clk_init(NULL);
426 	/*
427 	 * Traverses flattened DeviceTree - registering platform devices
428 	 * (if any) complete with their resources
429 	 */
430 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
431 
432 	if (machine_desc->init_machine)
433 		machine_desc->init_machine();
434 
435 	return 0;
436 }
437 arch_initcall(customize_machine);
438 
439 static int __init init_late_machine(void)
440 {
441 	if (machine_desc->init_late)
442 		machine_desc->init_late();
443 
444 	return 0;
445 }
446 late_initcall(init_late_machine);
447 /*
448  *  Get CPU information for use by the procfs.
449  */
450 
451 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
452 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
453 
454 static int show_cpuinfo(struct seq_file *m, void *v)
455 {
456 	char *str;
457 	int cpu_id = ptr_to_cpu(v);
458 
459 	if (!cpu_online(cpu_id)) {
460 		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
461 		goto done;
462 	}
463 
464 	str = (char *)__get_free_page(GFP_TEMPORARY);
465 	if (!str)
466 		goto done;
467 
468 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
469 
470 	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
471 		   loops_per_jiffy / (500000 / HZ),
472 		   (loops_per_jiffy / (5000 / HZ)) % 100);
473 
474 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
475 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
476 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
477 	seq_printf(m, arc_platform_smp_cpuinfo());
478 
479 	free_page((unsigned long)str);
480 done:
481 	seq_printf(m, "\n");
482 
483 	return 0;
484 }
485 
486 static void *c_start(struct seq_file *m, loff_t *pos)
487 {
488 	/*
489 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
490 	 * However since NULL is also a valid cpu-id (0), we use a round-about
491 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
492 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
493 	 */
494 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
495 }
496 
497 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
498 {
499 	++*pos;
500 	return c_start(m, pos);
501 }
502 
503 static void c_stop(struct seq_file *m, void *v)
504 {
505 }
506 
507 const struct seq_operations cpuinfo_op = {
508 	.start	= c_start,
509 	.next	= c_next,
510 	.stop	= c_stop,
511 	.show	= show_cpuinfo
512 };
513 
514 static DEFINE_PER_CPU(struct cpu, cpu_topology);
515 
516 static int __init topology_init(void)
517 {
518 	int cpu;
519 
520 	for_each_present_cpu(cpu)
521 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
522 
523 	return 0;
524 }
525 
526 subsys_initcall(topology_init);
527