xref: /openbmc/linux/arch/arc/kernel/setup.c (revision cd5d5810)
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;
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 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 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
51 
52 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
53 	cpu->uncached_base = uncached_space.start << 24;
54 
55 	cpu->extn.mul = read_aux_reg(ARC_REG_MUL_BCR);
56 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR);
57 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR);
58 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR);
59 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR);
60 	READ_BCR(ARC_REG_MAC_BCR, cpu->extn_mac_mul);
61 
62 	cpu->extn.ext_arith = read_aux_reg(ARC_REG_EXTARITH_BCR);
63 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR);
64 
65 	/* Note that we read the CCM BCRs independent of kernel config
66 	 * This is to catch the cases where user doesn't know that
67 	 * CCMs are present in hardware build
68 	 */
69 	{
70 		struct bcr_iccm iccm;
71 		struct bcr_dccm dccm;
72 		struct bcr_dccm_base dccm_base;
73 		unsigned int bcr_32bit_val;
74 
75 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
76 		if (bcr_32bit_val) {
77 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
78 			cpu->iccm.base_addr = iccm.base << 16;
79 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
80 		}
81 
82 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
83 		if (bcr_32bit_val) {
84 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
85 			cpu->dccm.sz = 0x800 << (dccm.sz);
86 
87 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
88 			cpu->dccm.base_addr = dccm_base.addr << 8;
89 		}
90 	}
91 
92 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
93 
94 	read_decode_mmu_bcr();
95 	read_decode_cache_bcr();
96 
97 	READ_BCR(ARC_REG_FP_BCR, cpu->fp);
98 	READ_BCR(ARC_REG_DPFP_BCR, cpu->dpfp);
99 }
100 
101 static const struct cpuinfo_data arc_cpu_tbl[] = {
102 	{ {0x10, "ARCTangent A5"}, 0x1F},
103 	{ {0x20, "ARC 600"      }, 0x2F},
104 	{ {0x30, "ARC 700"      }, 0x33},
105 	{ {0x34, "ARC 700 R4.10"}, 0x34},
106 	{ {0x00, NULL		} }
107 };
108 
109 char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
110 {
111 	int n = 0;
112 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
113 	struct bcr_identity *core = &cpu->core;
114 	const struct cpuinfo_data *tbl;
115 	int be = 0;
116 #ifdef CONFIG_CPU_BIG_ENDIAN
117 	be = 1;
118 #endif
119 	FIX_PTR(cpu);
120 
121 	n += scnprintf(buf + n, len - n,
122 		       "\nARC IDENTITY\t: Family [%#02x]"
123 		       " Cpu-id [%#02x] Chip-id [%#4x]\n",
124 		       core->family, core->cpu_id,
125 		       core->chip_id);
126 
127 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
128 		if ((core->family >= tbl->info.id) &&
129 		    (core->family <= tbl->up_range)) {
130 			n += scnprintf(buf + n, len - n,
131 				       "processor\t: %s %s\n",
132 				       tbl->info.str,
133 				       be ? "[Big Endian]" : "");
134 			break;
135 		}
136 	}
137 
138 	if (tbl->info.id == 0)
139 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
140 
141 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
142 		       (unsigned int)(arc_get_core_freq() / 1000000),
143 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
144 
145 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s %s\n",
146 		       (cpu->timers & 0x200) ? "TIMER1" : "",
147 		       (cpu->timers & 0x100) ? "TIMER0" : "");
148 
149 	n += scnprintf(buf + n, len - n, "Vect Tbl Base\t: %#x\n",
150 		       cpu->vec_base);
151 
152 	n += scnprintf(buf + n, len - n, "UNCACHED Base\t: %#x\n",
153 		       cpu->uncached_base);
154 
155 	return buf;
156 }
157 
158 static const struct id_to_str mul_type_nm[] = {
159 	{ 0x0, "N/A"},
160 	{ 0x1, "32x32 (spl Result Reg)" },
161 	{ 0x2, "32x32 (ANY Result Reg)" }
162 };
163 
164 static const struct id_to_str mac_mul_nm[] = {
165 	{0x0, "N/A"},
166 	{0x1, "N/A"},
167 	{0x2, "Dual 16 x 16"},
168 	{0x3, "N/A"},
169 	{0x4, "32x16"},
170 	{0x5, "N/A"},
171 	{0x6, "Dual 16x16 and 32x16"}
172 };
173 
174 char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
175 {
176 	int n = 0;
177 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
178 
179 	FIX_PTR(cpu);
180 #define IS_AVAIL1(var, str)	((var) ? str : "")
181 #define IS_AVAIL2(var, str)	((var == 0x2) ? str : "")
182 #define IS_USED(cfg)		(IS_ENABLED(cfg) ? "(in-use)" : "(not used)")
183 
184 	n += scnprintf(buf + n, len - n,
185 		       "Extn [700-Base]\t: %s %s %s %s %s %s\n",
186 		       IS_AVAIL2(cpu->extn.norm, "norm,"),
187 		       IS_AVAIL2(cpu->extn.barrel, "barrel-shift,"),
188 		       IS_AVAIL1(cpu->extn.swap, "swap,"),
189 		       IS_AVAIL2(cpu->extn.minmax, "minmax,"),
190 		       IS_AVAIL1(cpu->extn.crc, "crc,"),
191 		       IS_AVAIL2(cpu->extn.ext_arith, "ext-arith"));
192 
193 	n += scnprintf(buf + n, len - n, "Extn [700-MPY]\t: %s",
194 		       mul_type_nm[cpu->extn.mul].str);
195 
196 	n += scnprintf(buf + n, len - n, "   MAC MPY: %s\n",
197 		       mac_mul_nm[cpu->extn_mac_mul.type].str);
198 
199 	if (cpu->core.family == 0x34) {
200 		n += scnprintf(buf + n, len - n,
201 		"Extn [700-4.10]\t: LLOCK/SCOND %s, SWAPE %s, RTSC %s\n",
202 			       IS_USED(CONFIG_ARC_HAS_LLSC),
203 			       IS_USED(CONFIG_ARC_HAS_SWAPE),
204 			       IS_USED(CONFIG_ARC_HAS_RTSC));
205 	}
206 
207 	n += scnprintf(buf + n, len - n, "Extn [CCM]\t: %s",
208 		       !(cpu->dccm.sz || cpu->iccm.sz) ? "N/A" : "");
209 
210 	if (cpu->dccm.sz)
211 		n += scnprintf(buf + n, len - n, "DCCM: @ %x, %d KB ",
212 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz));
213 
214 	if (cpu->iccm.sz)
215 		n += scnprintf(buf + n, len - n, "ICCM: @ %x, %d KB",
216 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
217 
218 	n += scnprintf(buf + n, len - n, "\nExtn [FPU]\t: %s",
219 		       !(cpu->fp.ver || cpu->dpfp.ver) ? "N/A" : "");
220 
221 	if (cpu->fp.ver)
222 		n += scnprintf(buf + n, len - n, "SP [v%d] %s",
223 			       cpu->fp.ver, cpu->fp.fast ? "(fast)" : "");
224 
225 	if (cpu->dpfp.ver)
226 		n += scnprintf(buf + n, len - n, "DP [v%d] %s",
227 			       cpu->dpfp.ver, cpu->dpfp.fast ? "(fast)" : "");
228 
229 	n += scnprintf(buf + n, len - n, "\n");
230 
231 	n += scnprintf(buf + n, len - n,
232 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
233 
234 	return buf;
235 }
236 
237 void arc_chk_ccms(void)
238 {
239 #if defined(CONFIG_ARC_HAS_DCCM) || defined(CONFIG_ARC_HAS_ICCM)
240 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
241 
242 #ifdef CONFIG_ARC_HAS_DCCM
243 	/*
244 	 * DCCM can be arbit placed in hardware.
245 	 * Make sure it's placement/sz matches what Linux is built with
246 	 */
247 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
248 		panic("Linux built with incorrect DCCM Base address\n");
249 
250 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
251 		panic("Linux built with incorrect DCCM Size\n");
252 #endif
253 
254 #ifdef CONFIG_ARC_HAS_ICCM
255 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
256 		panic("Linux built with incorrect ICCM Size\n");
257 #endif
258 #endif
259 }
260 
261 /*
262  * Ensure that FP hardware and kernel config match
263  * -If hardware contains DPFP, kernel needs to save/restore FPU state
264  *  across context switches
265  * -If hardware lacks DPFP, but kernel configured to save FPU state then
266  *  kernel trying to access non-existant DPFP regs will crash
267  *
268  * We only check for Dbl precision Floating Point, because only DPFP
269  * hardware has dedicated regs which need to be saved/restored on ctx-sw
270  * (Single Precision uses core regs), thus kernel is kind of oblivious to it
271  */
272 void arc_chk_fpu(void)
273 {
274 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
275 
276 	if (cpu->dpfp.ver) {
277 #ifndef CONFIG_ARC_FPU_SAVE_RESTORE
278 		pr_warn("DPFP support broken in this kernel...\n");
279 #endif
280 	} else {
281 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
282 		panic("H/w lacks DPFP support, apps won't work\n");
283 #endif
284 	}
285 }
286 
287 /*
288  * Initialize and setup the processor core
289  * This is called by all the CPUs thus should not do special case stuff
290  *    such as only for boot CPU etc
291  */
292 
293 void setup_processor(void)
294 {
295 	char str[512];
296 	int cpu_id = smp_processor_id();
297 
298 	read_arc_build_cfg_regs();
299 	arc_init_IRQ();
300 
301 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
302 
303 	arc_mmu_init();
304 	arc_cache_init();
305 	arc_chk_ccms();
306 
307 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
308 
309 #ifdef CONFIG_SMP
310 	printk(arc_platform_smp_cpuinfo());
311 #endif
312 
313 	arc_chk_fpu();
314 }
315 
316 void __init setup_arch(char **cmdline_p)
317 {
318 	/* This also populates @boot_command_line from /bootargs */
319 	machine_desc = setup_machine_fdt(__dtb_start);
320 	if (!machine_desc)
321 		panic("Embedded DT invalid\n");
322 
323 	/* Append any u-boot provided cmdline */
324 #ifdef CONFIG_CMDLINE_UBOOT
325 	/* Add a whitespace seperator between the 2 cmdlines */
326 	strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
327 	strlcat(boot_command_line, command_line, COMMAND_LINE_SIZE);
328 #endif
329 
330 	/* Save unparsed command line copy for /proc/cmdline */
331 	*cmdline_p = boot_command_line;
332 
333 	/* To force early parsing of things like mem=xxx */
334 	parse_early_param();
335 
336 	/* Platform/board specific: e.g. early console registration */
337 	if (machine_desc->init_early)
338 		machine_desc->init_early();
339 
340 	setup_processor();
341 
342 #ifdef CONFIG_SMP
343 	smp_init_cpus();
344 #endif
345 
346 	setup_arch_memory();
347 
348 	/* copy flat DT out of .init and then unflatten it */
349 	copy_devtree();
350 	unflatten_device_tree();
351 
352 	/* Can be issue if someone passes cmd line arg "ro"
353 	 * But that is unlikely so keeping it as it is
354 	 */
355 	root_mountflags &= ~MS_RDONLY;
356 
357 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
358 	conswitchp = &dummy_con;
359 #endif
360 
361 	arc_unwind_init();
362 	arc_unwind_setup();
363 }
364 
365 static int __init customize_machine(void)
366 {
367 	/* Add platform devices */
368 	if (machine_desc->init_machine)
369 		machine_desc->init_machine();
370 
371 	return 0;
372 }
373 arch_initcall(customize_machine);
374 
375 static int __init init_late_machine(void)
376 {
377 	if (machine_desc->init_late)
378 		machine_desc->init_late();
379 
380 	return 0;
381 }
382 late_initcall(init_late_machine);
383 /*
384  *  Get CPU information for use by the procfs.
385  */
386 
387 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
388 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
389 
390 static int show_cpuinfo(struct seq_file *m, void *v)
391 {
392 	char *str;
393 	int cpu_id = ptr_to_cpu(v);
394 
395 	str = (char *)__get_free_page(GFP_TEMPORARY);
396 	if (!str)
397 		goto done;
398 
399 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
400 
401 	seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n",
402 		   loops_per_jiffy / (500000 / HZ),
403 		   (loops_per_jiffy / (5000 / HZ)) % 100);
404 
405 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
406 
407 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
408 
409 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
410 
411 #ifdef CONFIG_SMP
412 	seq_printf(m, arc_platform_smp_cpuinfo());
413 #endif
414 
415 	free_page((unsigned long)str);
416 done:
417 	seq_printf(m, "\n\n");
418 
419 	return 0;
420 }
421 
422 static void *c_start(struct seq_file *m, loff_t *pos)
423 {
424 	/*
425 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
426 	 * However since NULL is also a valid cpu-id (0), we use a round-about
427 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
428 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
429 	 */
430 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
431 }
432 
433 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
434 {
435 	++*pos;
436 	return c_start(m, pos);
437 }
438 
439 static void c_stop(struct seq_file *m, void *v)
440 {
441 }
442 
443 const struct seq_operations cpuinfo_op = {
444 	.start	= c_start,
445 	.next	= c_next,
446 	.stop	= c_stop,
447 	.show	= show_cpuinfo
448 };
449 
450 static DEFINE_PER_CPU(struct cpu, cpu_topology);
451 
452 static int __init topology_init(void)
453 {
454 	int cpu;
455 
456 	for_each_present_cpu(cpu)
457 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
458 
459 	return 0;
460 }
461 
462 subsys_initcall(topology_init);
463