xref: /openbmc/linux/arch/arc/kernel/setup.c (revision bbde9fc1824aab58bc78c084163007dd6c03fe5b) 
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 #ifdef CONFIG_ISA_ARCOMPACT
146 	{ {0x20, "ARC 600"      }, 0x2F},
147 	{ {0x30, "ARC 700"      }, 0x33},
148 	{ {0x34, "ARC 700 R4.10"}, 0x34},
149 	{ {0x35, "ARC 700 R4.11"}, 0x35},
150 #else
151 	{ {0x50, "ARC HS38 R2.0"}, 0x51},
152 	{ {0x52, "ARC HS38 R2.1"}, 0x52},
153 #endif
154 	{ {0x00, NULL		} }
155 };
156 
157 #define IS_AVAIL1(v, s)		((v) ? s : "")
158 #define IS_USED_RUN(v)		((v) ? "" : "(not used) ")
159 #define IS_USED_CFG(cfg)	IS_USED_RUN(IS_ENABLED(cfg))
160 #define IS_AVAIL2(v, s, cfg)	IS_AVAIL1(v, s), IS_AVAIL1(v, IS_USED_CFG(cfg))
161 
162 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
163 {
164 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
165 	struct bcr_identity *core = &cpu->core;
166 	const struct cpuinfo_data *tbl;
167 	char *isa_nm;
168 	int i, be, atomic;
169 	int n = 0;
170 
171 	FIX_PTR(cpu);
172 
173 	if (is_isa_arcompact()) {
174 		isa_nm = "ARCompact";
175 		be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
176 
177 		atomic = cpu->isa.atomic1;
178 		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
179 			atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
180 	} else {
181 		isa_nm = "ARCv2";
182 		be = cpu->isa.be;
183 		atomic = cpu->isa.atomic;
184 	}
185 
186 	n += scnprintf(buf + n, len - n,
187 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
188 		       core->family, core->cpu_id, core->chip_id);
189 
190 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
191 		if ((core->family >= tbl->info.id) &&
192 		    (core->family <= tbl->up_range)) {
193 			n += scnprintf(buf + n, len - n,
194 				       "processor [%d]\t: %s (%s ISA) %s\n",
195 				       cpu_id, tbl->info.str, isa_nm,
196 				       IS_AVAIL1(be, "[Big-Endian]"));
197 			break;
198 		}
199 	}
200 
201 	if (tbl->info.id == 0)
202 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
203 
204 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
205 		       (unsigned int)(arc_get_core_freq() / 1000000),
206 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
207 
208 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
209 		       IS_AVAIL1(cpu->timers.t0, "Timer0 "),
210 		       IS_AVAIL1(cpu->timers.t1, "Timer1 "),
211 		       IS_AVAIL2(cpu->timers.rtc, "64-bit RTC ",
212 				 CONFIG_ARC_HAS_RTC));
213 
214 	n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
215 			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
216 			   IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
217 			   IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
218 
219 	if (i)
220 		n += scnprintf(buf + n, len - n, "\n\t\t: ");
221 
222 	if (cpu->extn_mpy.ver) {
223 		if (cpu->extn_mpy.ver <= 0x2) {	/* ARCompact */
224 			n += scnprintf(buf + n, len - n, "mpy ");
225 		} else {
226 			int opt = 2;	/* stock MPY/MPYH */
227 
228 			if (cpu->extn_mpy.dsp)	/* OPT 7-9 */
229 				opt = cpu->extn_mpy.dsp + 6;
230 
231 			n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
232 		}
233 		n += scnprintf(buf + n, len - n, "%s",
234 			       IS_USED_CFG(CONFIG_ARC_HAS_HW_MPY));
235 	}
236 
237 	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
238 		       IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
239 		       IS_AVAIL1(cpu->extn.norm, "norm "),
240 		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
241 		       IS_AVAIL1(cpu->extn.swap, "swap "),
242 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
243 		       IS_AVAIL1(cpu->extn.crc, "crc "),
244 		       IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
245 
246 	if (cpu->bpu.ver)
247 		n += scnprintf(buf + n, len - n,
248 			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
249 			      IS_AVAIL1(cpu->bpu.full, "full"),
250 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
251 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
252 
253 	return buf;
254 }
255 
256 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
257 {
258 	int n = 0;
259 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
260 
261 	FIX_PTR(cpu);
262 
263 	n += scnprintf(buf + n, len - n,
264 		       "Vector Table\t: %#x\nUncached Base\t: %#x\n",
265 		       cpu->vec_base, ARC_UNCACHED_ADDR_SPACE);
266 
267 	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
268 		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
269 			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
270 			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
271 
272 	if (cpu->extn.debug)
273 		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
274 			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
275 			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
276 			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
277 
278 	if (cpu->dccm.sz || cpu->iccm.sz)
279 		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
280 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
281 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
282 
283 	n += scnprintf(buf + n, len - n,
284 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
285 
286 	return buf;
287 }
288 
289 static void arc_chk_core_config(void)
290 {
291 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
292 	int fpu_enabled;
293 
294 	if (!cpu->timers.t0)
295 		panic("Timer0 is not present!\n");
296 
297 	if (!cpu->timers.t1)
298 		panic("Timer1 is not present!\n");
299 
300 	if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->timers.rtc)
301 		panic("RTC is not present\n");
302 
303 #ifdef CONFIG_ARC_HAS_DCCM
304 	/*
305 	 * DCCM can be arbit placed in hardware.
306 	 * Make sure it's placement/sz matches what Linux is built with
307 	 */
308 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
309 		panic("Linux built with incorrect DCCM Base address\n");
310 
311 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
312 		panic("Linux built with incorrect DCCM Size\n");
313 #endif
314 
315 #ifdef CONFIG_ARC_HAS_ICCM
316 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
317 		panic("Linux built with incorrect ICCM Size\n");
318 #endif
319 
320 	/*
321 	 * FP hardware/software config sanity
322 	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
323 	 * -If not, it will crash trying to save/restore the non-existant regs
324 	 *
325 	 * (only DPDP checked since SP has no arch visible regs)
326 	 */
327 	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
328 
329 	if (cpu->extn.fpu_dp && !fpu_enabled)
330 		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
331 	else if (!cpu->extn.fpu_dp && fpu_enabled)
332 		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
333 }
334 
335 /*
336  * Initialize and setup the processor core
337  * This is called by all the CPUs thus should not do special case stuff
338  *    such as only for boot CPU etc
339  */
340 
341 void setup_processor(void)
342 {
343 	char str[512];
344 	int cpu_id = smp_processor_id();
345 
346 	read_arc_build_cfg_regs();
347 	arc_init_IRQ();
348 
349 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
350 
351 	arc_mmu_init();
352 	arc_cache_init();
353 
354 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
355 	printk(arc_platform_smp_cpuinfo());
356 
357 	arc_chk_core_config();
358 }
359 
360 static inline int is_kernel(unsigned long addr)
361 {
362 	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
363 		return 1;
364 	return 0;
365 }
366 
367 void __init setup_arch(char **cmdline_p)
368 {
369 #ifdef CONFIG_ARC_UBOOT_SUPPORT
370 	/* make sure that uboot passed pointer to cmdline/dtb is valid */
371 	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
372 		panic("Invalid uboot arg\n");
373 
374 	/* See if u-boot passed an external Device Tree blob */
375 	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
376 	if (!machine_desc)
377 #endif
378 	{
379 		/* No, so try the embedded one */
380 		machine_desc = setup_machine_fdt(__dtb_start);
381 		if (!machine_desc)
382 			panic("Embedded DT invalid\n");
383 
384 		/*
385 		 * If we are here, it is established that @uboot_arg didn't
386 		 * point to DT blob. Instead if u-boot says it is cmdline,
387 		 * Appent to embedded DT cmdline.
388 		 * setup_machine_fdt() would have populated @boot_command_line
389 		 */
390 		if (uboot_tag == 1) {
391 			/* Ensure a whitespace between the 2 cmdlines */
392 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
393 			strlcat(boot_command_line, uboot_arg,
394 				COMMAND_LINE_SIZE);
395 		}
396 	}
397 
398 	/* Save unparsed command line copy for /proc/cmdline */
399 	*cmdline_p = boot_command_line;
400 
401 	/* To force early parsing of things like mem=xxx */
402 	parse_early_param();
403 
404 	/* Platform/board specific: e.g. early console registration */
405 	if (machine_desc->init_early)
406 		machine_desc->init_early();
407 
408 	setup_processor();
409 	smp_init_cpus();
410 	setup_arch_memory();
411 
412 	/* copy flat DT out of .init and then unflatten it */
413 	unflatten_and_copy_device_tree();
414 
415 	/* Can be issue if someone passes cmd line arg "ro"
416 	 * But that is unlikely so keeping it as it is
417 	 */
418 	root_mountflags &= ~MS_RDONLY;
419 
420 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
421 	conswitchp = &dummy_con;
422 #endif
423 
424 	arc_unwind_init();
425 	arc_unwind_setup();
426 }
427 
428 static int __init customize_machine(void)
429 {
430 	of_clk_init(NULL);
431 	/*
432 	 * Traverses flattened DeviceTree - registering platform devices
433 	 * (if any) complete with their resources
434 	 */
435 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
436 
437 	if (machine_desc->init_machine)
438 		machine_desc->init_machine();
439 
440 	return 0;
441 }
442 arch_initcall(customize_machine);
443 
444 static int __init init_late_machine(void)
445 {
446 	if (machine_desc->init_late)
447 		machine_desc->init_late();
448 
449 	return 0;
450 }
451 late_initcall(init_late_machine);
452 /*
453  *  Get CPU information for use by the procfs.
454  */
455 
456 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
457 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
458 
459 static int show_cpuinfo(struct seq_file *m, void *v)
460 {
461 	char *str;
462 	int cpu_id = ptr_to_cpu(v);
463 
464 	if (!cpu_online(cpu_id)) {
465 		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
466 		goto done;
467 	}
468 
469 	str = (char *)__get_free_page(GFP_TEMPORARY);
470 	if (!str)
471 		goto done;
472 
473 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
474 
475 	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
476 		   loops_per_jiffy / (500000 / HZ),
477 		   (loops_per_jiffy / (5000 / HZ)) % 100);
478 
479 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
480 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
481 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
482 	seq_printf(m, arc_platform_smp_cpuinfo());
483 
484 	free_page((unsigned long)str);
485 done:
486 	seq_printf(m, "\n");
487 
488 	return 0;
489 }
490 
491 static void *c_start(struct seq_file *m, loff_t *pos)
492 {
493 	/*
494 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
495 	 * However since NULL is also a valid cpu-id (0), we use a round-about
496 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
497 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
498 	 */
499 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
500 }
501 
502 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
503 {
504 	++*pos;
505 	return c_start(m, pos);
506 }
507 
508 static void c_stop(struct seq_file *m, void *v)
509 {
510 }
511 
512 const struct seq_operations cpuinfo_op = {
513 	.start	= c_start,
514 	.next	= c_next,
515 	.stop	= c_stop,
516 	.show	= show_cpuinfo
517 };
518 
519 static DEFINE_PER_CPU(struct cpu, cpu_topology);
520 
521 static int __init topology_init(void)
522 {
523 	int cpu;
524 
525 	for_each_present_cpu(cpu)
526 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
527 
528 	return 0;
529 }
530 
531 subsys_initcall(topology_init);
532