xref: /openbmc/linux/arch/arc/kernel/setup.c (revision 8684014d)
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 /* Part of U-boot ABI: see head.S */
34 int __initdata uboot_tag;
35 char __initdata *uboot_arg;
36 
37 const struct machine_desc *machine_desc;
38 
39 struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
40 
41 struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
42 
43 static void read_arc_build_cfg_regs(void)
44 {
45 	struct bcr_perip uncached_space;
46 	struct bcr_generic bcr;
47 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
48 	FIX_PTR(cpu);
49 
50 	READ_BCR(AUX_IDENTITY, cpu->core);
51 	READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
52 
53 	READ_BCR(ARC_REG_TIMERS_BCR, cpu->timers);
54 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
55 
56 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
57 	cpu->uncached_base = uncached_space.start << 24;
58 
59 	READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
60 
61 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
62 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
63 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
64 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
65 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
66 
67 	/* Note that we read the CCM BCRs independent of kernel config
68 	 * This is to catch the cases where user doesn't know that
69 	 * CCMs are present in hardware build
70 	 */
71 	{
72 		struct bcr_iccm iccm;
73 		struct bcr_dccm dccm;
74 		struct bcr_dccm_base dccm_base;
75 		unsigned int bcr_32bit_val;
76 
77 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
78 		if (bcr_32bit_val) {
79 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
80 			cpu->iccm.base_addr = iccm.base << 16;
81 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
82 		}
83 
84 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
85 		if (bcr_32bit_val) {
86 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
87 			cpu->dccm.sz = 0x800 << (dccm.sz);
88 
89 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
90 			cpu->dccm.base_addr = dccm_base.addr << 8;
91 		}
92 	}
93 
94 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
95 
96 	read_decode_mmu_bcr();
97 	read_decode_cache_bcr();
98 
99 	{
100 		struct bcr_fp_arcompact sp, dp;
101 		struct bcr_bpu_arcompact bpu;
102 
103 		READ_BCR(ARC_REG_FP_BCR, sp);
104 		READ_BCR(ARC_REG_DPFP_BCR, dp);
105 		cpu->extn.fpu_sp = sp.ver ? 1 : 0;
106 		cpu->extn.fpu_dp = dp.ver ? 1 : 0;
107 
108 		READ_BCR(ARC_REG_BPU_BCR, bpu);
109 		cpu->bpu.ver = bpu.ver;
110 		cpu->bpu.full = bpu.fam ? 1 : 0;
111 		if (bpu.ent) {
112 			cpu->bpu.num_cache = 256 << (bpu.ent - 1);
113 			cpu->bpu.num_pred = 256 << (bpu.ent - 1);
114 		}
115 	}
116 
117 	READ_BCR(ARC_REG_AP_BCR, bcr);
118 	cpu->extn.ap = bcr.ver ? 1 : 0;
119 
120 	READ_BCR(ARC_REG_SMART_BCR, bcr);
121 	cpu->extn.smart = bcr.ver ? 1 : 0;
122 
123 	cpu->extn.debug = cpu->extn.ap | cpu->extn.smart;
124 }
125 
126 static const struct cpuinfo_data arc_cpu_tbl[] = {
127 	{ {0x20, "ARC 600"      }, 0x2F},
128 	{ {0x30, "ARC 700"      }, 0x33},
129 	{ {0x34, "ARC 700 R4.10"}, 0x34},
130 	{ {0x35, "ARC 700 R4.11"}, 0x35},
131 	{ {0x00, NULL		} }
132 };
133 
134 #define IS_AVAIL1(v, str)	((v) ? str : "")
135 #define IS_USED(cfg)		(IS_ENABLED(cfg) ? "" : "(not used) ")
136 #define IS_AVAIL2(v, str, cfg)  IS_AVAIL1(v, str), IS_AVAIL1(v, IS_USED(cfg))
137 
138 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
139 {
140 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
141 	struct bcr_identity *core = &cpu->core;
142 	const struct cpuinfo_data *tbl;
143 	char *isa_nm;
144 	int i, be, atomic;
145 	int n = 0;
146 
147 	FIX_PTR(cpu);
148 
149 	{
150 		isa_nm = "ARCompact";
151 		be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
152 
153 		atomic = cpu->isa.atomic1;
154 		if (!cpu->isa.ver)	/* ISA BCR absent, use Kconfig info */
155 			atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
156 	}
157 
158 	n += scnprintf(buf + n, len - n,
159 		       "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
160 		       core->family, core->cpu_id, core->chip_id);
161 
162 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
163 		if ((core->family >= tbl->info.id) &&
164 		    (core->family <= tbl->up_range)) {
165 			n += scnprintf(buf + n, len - n,
166 				       "processor [%d]\t: %s (%s ISA) %s\n",
167 				       cpu_id, tbl->info.str, isa_nm,
168 				       IS_AVAIL1(be, "[Big-Endian]"));
169 			break;
170 		}
171 	}
172 
173 	if (tbl->info.id == 0)
174 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
175 
176 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
177 		       (unsigned int)(arc_get_core_freq() / 1000000),
178 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
179 
180 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
181 		       IS_AVAIL1(cpu->timers.t0, "Timer0 "),
182 		       IS_AVAIL1(cpu->timers.t1, "Timer1 "),
183 		       IS_AVAIL2(cpu->timers.rtsc, "64-bit RTSC ", CONFIG_ARC_HAS_RTSC));
184 
185 	n += i = scnprintf(buf + n, len - n, "%s%s",
186 			   IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC));
187 
188 	if (i)
189 		n += scnprintf(buf + n, len - n, "\n\t\t: ");
190 
191 	n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
192 		       IS_AVAIL1(cpu->extn_mpy.ver, "mpy "),
193 		       IS_AVAIL1(cpu->extn.norm, "norm "),
194 		       IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
195 		       IS_AVAIL1(cpu->extn.swap, "swap "),
196 		       IS_AVAIL1(cpu->extn.minmax, "minmax "),
197 		       IS_AVAIL1(cpu->extn.crc, "crc "),
198 		       IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
199 
200 	if (cpu->bpu.ver)
201 		n += scnprintf(buf + n, len - n,
202 			      "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
203 			      IS_AVAIL1(cpu->bpu.full, "full"),
204 			      IS_AVAIL1(!cpu->bpu.full, "partial"),
205 			      cpu->bpu.num_cache, cpu->bpu.num_pred);
206 
207 	return buf;
208 }
209 
210 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
211 {
212 	int n = 0;
213 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
214 
215 	FIX_PTR(cpu);
216 
217 	n += scnprintf(buf + n, len - n,
218 		       "Vector Table\t: %#x\nUncached Base\t: %#x\n",
219 		       cpu->vec_base, cpu->uncached_base);
220 
221 	if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
222 		n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
223 			       IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
224 			       IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
225 
226 	if (cpu->extn.debug)
227 		n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
228 			       IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
229 			       IS_AVAIL1(cpu->extn.smart, "smaRT "),
230 			       IS_AVAIL1(cpu->extn.rtt, "RTT "));
231 
232 	if (cpu->dccm.sz || cpu->iccm.sz)
233 		n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
234 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
235 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
236 
237 	n += scnprintf(buf + n, len - n,
238 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
239 
240 	return buf;
241 }
242 
243 static void arc_chk_core_config(void)
244 {
245 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
246 	int fpu_enabled;
247 
248 	if (!cpu->timers.t0)
249 		panic("Timer0 is not present!\n");
250 
251 	if (!cpu->timers.t1)
252 		panic("Timer1 is not present!\n");
253 
254 	if (IS_ENABLED(CONFIG_ARC_HAS_RTSC) && !cpu->timers.rtsc)
255 		panic("RTSC is not present\n");
256 
257 #ifdef CONFIG_ARC_HAS_DCCM
258 	/*
259 	 * DCCM can be arbit placed in hardware.
260 	 * Make sure it's placement/sz matches what Linux is built with
261 	 */
262 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
263 		panic("Linux built with incorrect DCCM Base address\n");
264 
265 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
266 		panic("Linux built with incorrect DCCM Size\n");
267 #endif
268 
269 #ifdef CONFIG_ARC_HAS_ICCM
270 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
271 		panic("Linux built with incorrect ICCM Size\n");
272 #endif
273 
274 	/*
275 	 * FP hardware/software config sanity
276 	 * -If hardware contains DPFP, kernel needs to save/restore FPU state
277 	 * -If not, it will crash trying to save/restore the non-existant regs
278 	 *
279 	 * (only DPDP checked since SP has no arch visible regs)
280 	 */
281 	fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
282 
283 	if (cpu->extn.fpu_dp && !fpu_enabled)
284 		pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
285 	else if (!cpu->extn.fpu_dp && fpu_enabled)
286 		panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
287 }
288 
289 /*
290  * Initialize and setup the processor core
291  * This is called by all the CPUs thus should not do special case stuff
292  *    such as only for boot CPU etc
293  */
294 
295 void setup_processor(void)
296 {
297 	char str[512];
298 	int cpu_id = smp_processor_id();
299 
300 	read_arc_build_cfg_regs();
301 	arc_init_IRQ();
302 
303 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
304 
305 	arc_mmu_init();
306 	arc_cache_init();
307 
308 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
309 	printk(arc_platform_smp_cpuinfo());
310 
311 	arc_chk_core_config();
312 }
313 
314 static inline int is_kernel(unsigned long addr)
315 {
316 	if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
317 		return 1;
318 	return 0;
319 }
320 
321 void __init setup_arch(char **cmdline_p)
322 {
323 	/* make sure that uboot passed pointer to cmdline/dtb is valid */
324 	if (uboot_tag && is_kernel((unsigned long)uboot_arg))
325 		panic("Invalid uboot arg\n");
326 
327 	/* See if u-boot passed an external Device Tree blob */
328 	machine_desc = setup_machine_fdt(uboot_arg);	/* uboot_tag == 2 */
329 	if (!machine_desc) {
330 		/* No, so try the embedded one */
331 		machine_desc = setup_machine_fdt(__dtb_start);
332 		if (!machine_desc)
333 			panic("Embedded DT invalid\n");
334 
335 		/*
336 		 * If we are here, it is established that @uboot_arg didn't
337 		 * point to DT blob. Instead if u-boot says it is cmdline,
338 		 * Appent to embedded DT cmdline.
339 		 * setup_machine_fdt() would have populated @boot_command_line
340 		 */
341 		if (uboot_tag == 1) {
342 			/* Ensure a whitespace between the 2 cmdlines */
343 			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
344 			strlcat(boot_command_line, uboot_arg,
345 				COMMAND_LINE_SIZE);
346 		}
347 	}
348 
349 	/* Save unparsed command line copy for /proc/cmdline */
350 	*cmdline_p = boot_command_line;
351 
352 	/* To force early parsing of things like mem=xxx */
353 	parse_early_param();
354 
355 	/* Platform/board specific: e.g. early console registration */
356 	if (machine_desc->init_early)
357 		machine_desc->init_early();
358 
359 	setup_processor();
360 	smp_init_cpus();
361 	setup_arch_memory();
362 
363 	/* copy flat DT out of .init and then unflatten it */
364 	unflatten_and_copy_device_tree();
365 
366 	/* Can be issue if someone passes cmd line arg "ro"
367 	 * But that is unlikely so keeping it as it is
368 	 */
369 	root_mountflags &= ~MS_RDONLY;
370 
371 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
372 	conswitchp = &dummy_con;
373 #endif
374 
375 	arc_unwind_init();
376 	arc_unwind_setup();
377 }
378 
379 static int __init customize_machine(void)
380 {
381 	of_clk_init(NULL);
382 	/*
383 	 * Traverses flattened DeviceTree - registering platform devices
384 	 * (if any) complete with their resources
385 	 */
386 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
387 
388 	if (machine_desc->init_machine)
389 		machine_desc->init_machine();
390 
391 	return 0;
392 }
393 arch_initcall(customize_machine);
394 
395 static int __init init_late_machine(void)
396 {
397 	if (machine_desc->init_late)
398 		machine_desc->init_late();
399 
400 	return 0;
401 }
402 late_initcall(init_late_machine);
403 /*
404  *  Get CPU information for use by the procfs.
405  */
406 
407 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
408 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
409 
410 static int show_cpuinfo(struct seq_file *m, void *v)
411 {
412 	char *str;
413 	int cpu_id = ptr_to_cpu(v);
414 
415 	str = (char *)__get_free_page(GFP_TEMPORARY);
416 	if (!str)
417 		goto done;
418 
419 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
420 
421 	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
422 		   loops_per_jiffy / (500000 / HZ),
423 		   (loops_per_jiffy / (5000 / HZ)) % 100);
424 
425 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
426 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
427 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
428 	seq_printf(m, arc_platform_smp_cpuinfo());
429 
430 	free_page((unsigned long)str);
431 done:
432 	seq_printf(m, "\n\n");
433 
434 	return 0;
435 }
436 
437 static void *c_start(struct seq_file *m, loff_t *pos)
438 {
439 	/*
440 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
441 	 * However since NULL is also a valid cpu-id (0), we use a round-about
442 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
443 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
444 	 */
445 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
446 }
447 
448 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
449 {
450 	++*pos;
451 	return c_start(m, pos);
452 }
453 
454 static void c_stop(struct seq_file *m, void *v)
455 {
456 }
457 
458 const struct seq_operations cpuinfo_op = {
459 	.start	= c_start,
460 	.next	= c_next,
461 	.stop	= c_stop,
462 	.show	= show_cpuinfo
463 };
464 
465 static DEFINE_PER_CPU(struct cpu, cpu_topology);
466 
467 static int __init topology_init(void)
468 {
469 	int cpu;
470 
471 	for_each_present_cpu(cpu)
472 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
473 
474 	return 0;
475 }
476 
477 subsys_initcall(topology_init);
478