xref: /openbmc/linux/arch/arc/kernel/setup.c (revision f35e839a) 
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/of_fdt.h>
17 #include <linux/cache.h>
18 #include <asm/sections.h>
19 #include <asm/arcregs.h>
20 #include <asm/tlb.h>
21 #include <asm/setup.h>
22 #include <asm/page.h>
23 #include <asm/irq.h>
24 #include <asm/prom.h>
25 #include <asm/unwind.h>
26 #include <asm/clk.h>
27 #include <asm/mach_desc.h>
28 
29 #define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
30 
31 int running_on_hw = 1;	/* vs. on ISS */
32 
33 char __initdata command_line[COMMAND_LINE_SIZE];
34 struct machine_desc *machine_desc __cpuinitdata;
35 
36 struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
37 
38 struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
39 
40 
41 void __cpuinit read_arc_build_cfg_regs(void)
42 {
43 	struct bcr_perip uncached_space;
44 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
45 	FIX_PTR(cpu);
46 
47 	READ_BCR(AUX_IDENTITY, cpu->core);
48 
49 	cpu->timers = read_aux_reg(ARC_REG_TIMERS_BCR);
50 
51 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
52 	if (cpu->vec_base == 0)
53 		cpu->vec_base = (unsigned int)_int_vec_base_lds;
54 
55 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
56 	cpu->uncached_base = uncached_space.start << 24;
57 
58 	cpu->extn.mul = read_aux_reg(ARC_REG_MUL_BCR);
59 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR);
60 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR);
61 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR);
62 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR);
63 	READ_BCR(ARC_REG_MAC_BCR, cpu->extn_mac_mul);
64 
65 	cpu->extn.ext_arith = read_aux_reg(ARC_REG_EXTARITH_BCR);
66 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR);
67 
68 	/* Note that we read the CCM BCRs independent of kernel config
69 	 * This is to catch the cases where user doesn't know that
70 	 * CCMs are present in hardware build
71 	 */
72 	{
73 		struct bcr_iccm iccm;
74 		struct bcr_dccm dccm;
75 		struct bcr_dccm_base dccm_base;
76 		unsigned int bcr_32bit_val;
77 
78 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
79 		if (bcr_32bit_val) {
80 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
81 			cpu->iccm.base_addr = iccm.base << 16;
82 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
83 		}
84 
85 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
86 		if (bcr_32bit_val) {
87 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
88 			cpu->dccm.sz = 0x800 << (dccm.sz);
89 
90 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
91 			cpu->dccm.base_addr = dccm_base.addr << 8;
92 		}
93 	}
94 
95 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
96 
97 	read_decode_mmu_bcr();
98 	read_decode_cache_bcr();
99 
100 	READ_BCR(ARC_REG_FP_BCR, cpu->fp);
101 	READ_BCR(ARC_REG_DPFP_BCR, cpu->dpfp);
102 }
103 
104 static const struct cpuinfo_data arc_cpu_tbl[] = {
105 	{ {0x10, "ARCTangent A5"}, 0x1F},
106 	{ {0x20, "ARC 600"      }, 0x2F},
107 	{ {0x30, "ARC 700"      }, 0x33},
108 	{ {0x34, "ARC 700 R4.10"}, 0x34},
109 	{ {0x00, NULL		} }
110 };
111 
112 char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
113 {
114 	int n = 0;
115 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
116 	struct bcr_identity *core = &cpu->core;
117 	const struct cpuinfo_data *tbl;
118 	int be = 0;
119 #ifdef CONFIG_CPU_BIG_ENDIAN
120 	be = 1;
121 #endif
122 	FIX_PTR(cpu);
123 
124 	n += scnprintf(buf + n, len - n,
125 		       "\nARC IDENTITY\t: Family [%#02x]"
126 		       " Cpu-id [%#02x] Chip-id [%#4x]\n",
127 		       core->family, core->cpu_id,
128 		       core->chip_id);
129 
130 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
131 		if ((core->family >= tbl->info.id) &&
132 		    (core->family <= tbl->up_range)) {
133 			n += scnprintf(buf + n, len - n,
134 				       "processor\t: %s %s\n",
135 				       tbl->info.str,
136 				       be ? "[Big Endian]" : "");
137 			break;
138 		}
139 	}
140 
141 	if (tbl->info.id == 0)
142 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
143 
144 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
145 		       (unsigned int)(arc_get_core_freq() / 1000000),
146 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
147 
148 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s %s\n",
149 		       (cpu->timers & 0x200) ? "TIMER1" : "",
150 		       (cpu->timers & 0x100) ? "TIMER0" : "");
151 
152 	n += scnprintf(buf + n, len - n, "Vect Tbl Base\t: %#x\n",
153 		       cpu->vec_base);
154 
155 	n += scnprintf(buf + n, len - n, "UNCACHED Base\t: %#x\n",
156 		       cpu->uncached_base);
157 
158 	return buf;
159 }
160 
161 static const struct id_to_str mul_type_nm[] = {
162 	{ 0x0, "N/A"},
163 	{ 0x1, "32x32 (spl Result Reg)" },
164 	{ 0x2, "32x32 (ANY Result Reg)" }
165 };
166 
167 static const struct id_to_str mac_mul_nm[] = {
168 	{0x0, "N/A"},
169 	{0x1, "N/A"},
170 	{0x2, "Dual 16 x 16"},
171 	{0x3, "N/A"},
172 	{0x4, "32x16"},
173 	{0x5, "N/A"},
174 	{0x6, "Dual 16x16 and 32x16"}
175 };
176 
177 char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
178 {
179 	int n = 0;
180 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
181 
182 	FIX_PTR(cpu);
183 #define IS_AVAIL1(var, str)	((var) ? str : "")
184 #define IS_AVAIL2(var, str)	((var == 0x2) ? str : "")
185 #define IS_USED(var)		((var) ? "(in-use)" : "(not used)")
186 
187 	n += scnprintf(buf + n, len - n,
188 		       "Extn [700-Base]\t: %s %s %s %s %s %s\n",
189 		       IS_AVAIL2(cpu->extn.norm, "norm,"),
190 		       IS_AVAIL2(cpu->extn.barrel, "barrel-shift,"),
191 		       IS_AVAIL1(cpu->extn.swap, "swap,"),
192 		       IS_AVAIL2(cpu->extn.minmax, "minmax,"),
193 		       IS_AVAIL1(cpu->extn.crc, "crc,"),
194 		       IS_AVAIL2(cpu->extn.ext_arith, "ext-arith"));
195 
196 	n += scnprintf(buf + n, len - n, "Extn [700-MPY]\t: %s",
197 		       mul_type_nm[cpu->extn.mul].str);
198 
199 	n += scnprintf(buf + n, len - n, "   MAC MPY: %s\n",
200 		       mac_mul_nm[cpu->extn_mac_mul.type].str);
201 
202 	if (cpu->core.family == 0x34) {
203 		n += scnprintf(buf + n, len - n,
204 		"Extn [700-4.10]\t: LLOCK/SCOND %s, SWAPE %s, RTSC %s\n",
205 			       IS_USED(__CONFIG_ARC_HAS_LLSC_VAL),
206 			       IS_USED(__CONFIG_ARC_HAS_SWAPE_VAL),
207 			       IS_USED(__CONFIG_ARC_HAS_RTSC_VAL));
208 	}
209 
210 	n += scnprintf(buf + n, len - n, "Extn [CCM]\t: %s",
211 		       !(cpu->dccm.sz || cpu->iccm.sz) ? "N/A" : "");
212 
213 	if (cpu->dccm.sz)
214 		n += scnprintf(buf + n, len - n, "DCCM: @ %x, %d KB ",
215 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz));
216 
217 	if (cpu->iccm.sz)
218 		n += scnprintf(buf + n, len - n, "ICCM: @ %x, %d KB",
219 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
220 
221 	n += scnprintf(buf + n, len - n, "\nExtn [FPU]\t: %s",
222 		       !(cpu->fp.ver || cpu->dpfp.ver) ? "N/A" : "");
223 
224 	if (cpu->fp.ver)
225 		n += scnprintf(buf + n, len - n, "SP [v%d] %s",
226 			       cpu->fp.ver, cpu->fp.fast ? "(fast)" : "");
227 
228 	if (cpu->dpfp.ver)
229 		n += scnprintf(buf + n, len - n, "DP [v%d] %s",
230 			       cpu->dpfp.ver, cpu->dpfp.fast ? "(fast)" : "");
231 
232 	n += scnprintf(buf + n, len - n, "\n");
233 
234 	n += scnprintf(buf + n, len - n,
235 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
236 
237 	return buf;
238 }
239 
240 void __cpuinit arc_chk_ccms(void)
241 {
242 #if defined(CONFIG_ARC_HAS_DCCM) || defined(CONFIG_ARC_HAS_ICCM)
243 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
244 
245 #ifdef CONFIG_ARC_HAS_DCCM
246 	/*
247 	 * DCCM can be arbit placed in hardware.
248 	 * Make sure it's placement/sz matches what Linux is built with
249 	 */
250 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
251 		panic("Linux built with incorrect DCCM Base address\n");
252 
253 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
254 		panic("Linux built with incorrect DCCM Size\n");
255 #endif
256 
257 #ifdef CONFIG_ARC_HAS_ICCM
258 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
259 		panic("Linux built with incorrect ICCM Size\n");
260 #endif
261 #endif
262 }
263 
264 /*
265  * Ensure that FP hardware and kernel config match
266  * -If hardware contains DPFP, kernel needs to save/restore FPU state
267  *  across context switches
268  * -If hardware lacks DPFP, but kernel configured to save FPU state then
269  *  kernel trying to access non-existant DPFP regs will crash
270  *
271  * We only check for Dbl precision Floating Point, because only DPFP
272  * hardware has dedicated regs which need to be saved/restored on ctx-sw
273  * (Single Precision uses core regs), thus kernel is kind of oblivious to it
274  */
275 void __cpuinit arc_chk_fpu(void)
276 {
277 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
278 
279 	if (cpu->dpfp.ver) {
280 #ifndef CONFIG_ARC_FPU_SAVE_RESTORE
281 		pr_warn("DPFP support broken in this kernel...\n");
282 #endif
283 	} else {
284 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
285 		panic("H/w lacks DPFP support, apps won't work\n");
286 #endif
287 	}
288 }
289 
290 /*
291  * Initialize and setup the processor core
292  * This is called by all the CPUs thus should not do special case stuff
293  *    such as only for boot CPU etc
294  */
295 
296 void __cpuinit setup_processor(void)
297 {
298 	char str[512];
299 	int cpu_id = smp_processor_id();
300 
301 	read_arc_build_cfg_regs();
302 	arc_init_IRQ();
303 
304 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
305 
306 	arc_mmu_init();
307 	arc_cache_init();
308 	arc_chk_ccms();
309 
310 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
311 
312 #ifdef CONFIG_SMP
313 	printk(arc_platform_smp_cpuinfo());
314 #endif
315 
316 	arc_chk_fpu();
317 }
318 
319 void __init setup_arch(char **cmdline_p)
320 {
321 	/* This also populates @boot_command_line from /bootargs */
322 	machine_desc = setup_machine_fdt(__dtb_start);
323 	if (!machine_desc)
324 		panic("Embedded DT invalid\n");
325 
326 	/* Append any u-boot provided cmdline */
327 #ifdef CONFIG_CMDLINE_UBOOT
328 	/* Add a whitespace seperator between the 2 cmdlines */
329 	strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
330 	strlcat(boot_command_line, command_line, COMMAND_LINE_SIZE);
331 #endif
332 
333 	/* Save unparsed command line copy for /proc/cmdline */
334 	*cmdline_p = boot_command_line;
335 
336 	/* To force early parsing of things like mem=xxx */
337 	parse_early_param();
338 
339 	/* Platform/board specific: e.g. early console registration */
340 	if (machine_desc->init_early)
341 		machine_desc->init_early();
342 
343 	setup_processor();
344 
345 #ifdef CONFIG_SMP
346 	smp_init_cpus();
347 #endif
348 
349 	setup_arch_memory();
350 
351 	/* copy flat DT out of .init and then unflatten it */
352 	copy_devtree();
353 	unflatten_device_tree();
354 
355 	/* Can be issue if someone passes cmd line arg "ro"
356 	 * But that is unlikely so keeping it as it is
357 	 */
358 	root_mountflags &= ~MS_RDONLY;
359 
360 	console_verbose();
361 
362 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
363 	conswitchp = &dummy_con;
364 #endif
365 
366 	arc_unwind_init();
367 	arc_unwind_setup();
368 }
369 
370 static int __init customize_machine(void)
371 {
372 	/* Add platform devices */
373 	if (machine_desc->init_machine)
374 		machine_desc->init_machine();
375 
376 	return 0;
377 }
378 arch_initcall(customize_machine);
379 
380 static int __init init_late_machine(void)
381 {
382 	if (machine_desc->init_late)
383 		machine_desc->init_late();
384 
385 	return 0;
386 }
387 late_initcall(init_late_machine);
388 /*
389  *  Get CPU information for use by the procfs.
390  */
391 
392 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
393 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
394 
395 static int show_cpuinfo(struct seq_file *m, void *v)
396 {
397 	char *str;
398 	int cpu_id = ptr_to_cpu(v);
399 
400 	str = (char *)__get_free_page(GFP_TEMPORARY);
401 	if (!str)
402 		goto done;
403 
404 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
405 
406 	seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n",
407 		   loops_per_jiffy / (500000 / HZ),
408 		   (loops_per_jiffy / (5000 / HZ)) % 100);
409 
410 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
411 
412 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
413 
414 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
415 
416 #ifdef CONFIG_SMP
417 	seq_printf(m, arc_platform_smp_cpuinfo());
418 #endif
419 
420 	free_page((unsigned long)str);
421 done:
422 	seq_printf(m, "\n\n");
423 
424 	return 0;
425 }
426 
427 static void *c_start(struct seq_file *m, loff_t *pos)
428 {
429 	/*
430 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
431 	 * However since NULL is also a valid cpu-id (0), we use a round-about
432 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
433 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
434 	 */
435 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
436 }
437 
438 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
439 {
440 	++*pos;
441 	return c_start(m, pos);
442 }
443 
444 static void c_stop(struct seq_file *m, void *v)
445 {
446 }
447 
448 const struct seq_operations cpuinfo_op = {
449 	.start	= c_start,
450 	.next	= c_next,
451 	.stop	= c_stop,
452 	.show	= show_cpuinfo
453 };
454 
455 static DEFINE_PER_CPU(struct cpu, cpu_topology);
456 
457 static int __init topology_init(void)
458 {
459 	int cpu;
460 
461 	for_each_present_cpu(cpu)
462 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
463 
464 	return 0;
465 }
466 
467 subsys_initcall(topology_init);
468