xref: /openbmc/linux/arch/arc/kernel/setup.c (revision 089a49b6)
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/unwind.h>
25 #include <asm/clk.h>
26 #include <asm/mach_desc.h>
27 
28 #define FIX_PTR(x)  __asm__ __volatile__(";" : "+r"(x))
29 
30 int running_on_hw = 1;	/* vs. on ISS */
31 
32 char __initdata command_line[COMMAND_LINE_SIZE];
33 const struct machine_desc *machine_desc;
34 
35 struct task_struct *_current_task[NR_CPUS];	/* For stack switching */
36 
37 struct cpuinfo_arc cpuinfo_arc700[NR_CPUS];
38 
39 
40 void read_arc_build_cfg_regs(void)
41 {
42 	struct bcr_perip uncached_space;
43 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
44 	FIX_PTR(cpu);
45 
46 	READ_BCR(AUX_IDENTITY, cpu->core);
47 
48 	cpu->timers = read_aux_reg(ARC_REG_TIMERS_BCR);
49 	cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
50 
51 	READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
52 	cpu->uncached_base = uncached_space.start << 24;
53 
54 	cpu->extn.mul = read_aux_reg(ARC_REG_MUL_BCR);
55 	cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR);
56 	cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR);
57 	cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR);
58 	cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR);
59 	READ_BCR(ARC_REG_MAC_BCR, cpu->extn_mac_mul);
60 
61 	cpu->extn.ext_arith = read_aux_reg(ARC_REG_EXTARITH_BCR);
62 	cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR);
63 
64 	/* Note that we read the CCM BCRs independent of kernel config
65 	 * This is to catch the cases where user doesn't know that
66 	 * CCMs are present in hardware build
67 	 */
68 	{
69 		struct bcr_iccm iccm;
70 		struct bcr_dccm dccm;
71 		struct bcr_dccm_base dccm_base;
72 		unsigned int bcr_32bit_val;
73 
74 		bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
75 		if (bcr_32bit_val) {
76 			iccm = *((struct bcr_iccm *)&bcr_32bit_val);
77 			cpu->iccm.base_addr = iccm.base << 16;
78 			cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
79 		}
80 
81 		bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
82 		if (bcr_32bit_val) {
83 			dccm = *((struct bcr_dccm *)&bcr_32bit_val);
84 			cpu->dccm.sz = 0x800 << (dccm.sz);
85 
86 			READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
87 			cpu->dccm.base_addr = dccm_base.addr << 8;
88 		}
89 	}
90 
91 	READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
92 
93 	read_decode_mmu_bcr();
94 	read_decode_cache_bcr();
95 
96 	READ_BCR(ARC_REG_FP_BCR, cpu->fp);
97 	READ_BCR(ARC_REG_DPFP_BCR, cpu->dpfp);
98 }
99 
100 static const struct cpuinfo_data arc_cpu_tbl[] = {
101 	{ {0x10, "ARCTangent A5"}, 0x1F},
102 	{ {0x20, "ARC 600"      }, 0x2F},
103 	{ {0x30, "ARC 700"      }, 0x33},
104 	{ {0x34, "ARC 700 R4.10"}, 0x34},
105 	{ {0x00, NULL		} }
106 };
107 
108 char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
109 {
110 	int n = 0;
111 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
112 	struct bcr_identity *core = &cpu->core;
113 	const struct cpuinfo_data *tbl;
114 	int be = 0;
115 #ifdef CONFIG_CPU_BIG_ENDIAN
116 	be = 1;
117 #endif
118 	FIX_PTR(cpu);
119 
120 	n += scnprintf(buf + n, len - n,
121 		       "\nARC IDENTITY\t: Family [%#02x]"
122 		       " Cpu-id [%#02x] Chip-id [%#4x]\n",
123 		       core->family, core->cpu_id,
124 		       core->chip_id);
125 
126 	for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
127 		if ((core->family >= tbl->info.id) &&
128 		    (core->family <= tbl->up_range)) {
129 			n += scnprintf(buf + n, len - n,
130 				       "processor\t: %s %s\n",
131 				       tbl->info.str,
132 				       be ? "[Big Endian]" : "");
133 			break;
134 		}
135 	}
136 
137 	if (tbl->info.id == 0)
138 		n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
139 
140 	n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
141 		       (unsigned int)(arc_get_core_freq() / 1000000),
142 		       (unsigned int)(arc_get_core_freq() / 10000) % 100);
143 
144 	n += scnprintf(buf + n, len - n, "Timers\t\t: %s %s\n",
145 		       (cpu->timers & 0x200) ? "TIMER1" : "",
146 		       (cpu->timers & 0x100) ? "TIMER0" : "");
147 
148 	n += scnprintf(buf + n, len - n, "Vect Tbl Base\t: %#x\n",
149 		       cpu->vec_base);
150 
151 	n += scnprintf(buf + n, len - n, "UNCACHED Base\t: %#x\n",
152 		       cpu->uncached_base);
153 
154 	return buf;
155 }
156 
157 static const struct id_to_str mul_type_nm[] = {
158 	{ 0x0, "N/A"},
159 	{ 0x1, "32x32 (spl Result Reg)" },
160 	{ 0x2, "32x32 (ANY Result Reg)" }
161 };
162 
163 static const struct id_to_str mac_mul_nm[] = {
164 	{0x0, "N/A"},
165 	{0x1, "N/A"},
166 	{0x2, "Dual 16 x 16"},
167 	{0x3, "N/A"},
168 	{0x4, "32x16"},
169 	{0x5, "N/A"},
170 	{0x6, "Dual 16x16 and 32x16"}
171 };
172 
173 char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
174 {
175 	int n = 0;
176 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
177 
178 	FIX_PTR(cpu);
179 #define IS_AVAIL1(var, str)	((var) ? str : "")
180 #define IS_AVAIL2(var, str)	((var == 0x2) ? str : "")
181 #define IS_USED(cfg)		(IS_ENABLED(cfg) ? "(in-use)" : "(not used)")
182 
183 	n += scnprintf(buf + n, len - n,
184 		       "Extn [700-Base]\t: %s %s %s %s %s %s\n",
185 		       IS_AVAIL2(cpu->extn.norm, "norm,"),
186 		       IS_AVAIL2(cpu->extn.barrel, "barrel-shift,"),
187 		       IS_AVAIL1(cpu->extn.swap, "swap,"),
188 		       IS_AVAIL2(cpu->extn.minmax, "minmax,"),
189 		       IS_AVAIL1(cpu->extn.crc, "crc,"),
190 		       IS_AVAIL2(cpu->extn.ext_arith, "ext-arith"));
191 
192 	n += scnprintf(buf + n, len - n, "Extn [700-MPY]\t: %s",
193 		       mul_type_nm[cpu->extn.mul].str);
194 
195 	n += scnprintf(buf + n, len - n, "   MAC MPY: %s\n",
196 		       mac_mul_nm[cpu->extn_mac_mul.type].str);
197 
198 	if (cpu->core.family == 0x34) {
199 		n += scnprintf(buf + n, len - n,
200 		"Extn [700-4.10]\t: LLOCK/SCOND %s, SWAPE %s, RTSC %s\n",
201 			       IS_USED(CONFIG_ARC_HAS_LLSC),
202 			       IS_USED(CONFIG_ARC_HAS_SWAPE),
203 			       IS_USED(CONFIG_ARC_HAS_RTSC));
204 	}
205 
206 	n += scnprintf(buf + n, len - n, "Extn [CCM]\t: %s",
207 		       !(cpu->dccm.sz || cpu->iccm.sz) ? "N/A" : "");
208 
209 	if (cpu->dccm.sz)
210 		n += scnprintf(buf + n, len - n, "DCCM: @ %x, %d KB ",
211 			       cpu->dccm.base_addr, TO_KB(cpu->dccm.sz));
212 
213 	if (cpu->iccm.sz)
214 		n += scnprintf(buf + n, len - n, "ICCM: @ %x, %d KB",
215 			       cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
216 
217 	n += scnprintf(buf + n, len - n, "\nExtn [FPU]\t: %s",
218 		       !(cpu->fp.ver || cpu->dpfp.ver) ? "N/A" : "");
219 
220 	if (cpu->fp.ver)
221 		n += scnprintf(buf + n, len - n, "SP [v%d] %s",
222 			       cpu->fp.ver, cpu->fp.fast ? "(fast)" : "");
223 
224 	if (cpu->dpfp.ver)
225 		n += scnprintf(buf + n, len - n, "DP [v%d] %s",
226 			       cpu->dpfp.ver, cpu->dpfp.fast ? "(fast)" : "");
227 
228 	n += scnprintf(buf + n, len - n, "\n");
229 
230 	n += scnprintf(buf + n, len - n,
231 		       "OS ABI [v3]\t: no-legacy-syscalls\n");
232 
233 	return buf;
234 }
235 
236 void arc_chk_ccms(void)
237 {
238 #if defined(CONFIG_ARC_HAS_DCCM) || defined(CONFIG_ARC_HAS_ICCM)
239 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
240 
241 #ifdef CONFIG_ARC_HAS_DCCM
242 	/*
243 	 * DCCM can be arbit placed in hardware.
244 	 * Make sure it's placement/sz matches what Linux is built with
245 	 */
246 	if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
247 		panic("Linux built with incorrect DCCM Base address\n");
248 
249 	if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
250 		panic("Linux built with incorrect DCCM Size\n");
251 #endif
252 
253 #ifdef CONFIG_ARC_HAS_ICCM
254 	if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
255 		panic("Linux built with incorrect ICCM Size\n");
256 #endif
257 #endif
258 }
259 
260 /*
261  * Ensure that FP hardware and kernel config match
262  * -If hardware contains DPFP, kernel needs to save/restore FPU state
263  *  across context switches
264  * -If hardware lacks DPFP, but kernel configured to save FPU state then
265  *  kernel trying to access non-existant DPFP regs will crash
266  *
267  * We only check for Dbl precision Floating Point, because only DPFP
268  * hardware has dedicated regs which need to be saved/restored on ctx-sw
269  * (Single Precision uses core regs), thus kernel is kind of oblivious to it
270  */
271 void arc_chk_fpu(void)
272 {
273 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
274 
275 	if (cpu->dpfp.ver) {
276 #ifndef CONFIG_ARC_FPU_SAVE_RESTORE
277 		pr_warn("DPFP support broken in this kernel...\n");
278 #endif
279 	} else {
280 #ifdef CONFIG_ARC_FPU_SAVE_RESTORE
281 		panic("H/w lacks DPFP support, apps won't work\n");
282 #endif
283 	}
284 }
285 
286 /*
287  * Initialize and setup the processor core
288  * This is called by all the CPUs thus should not do special case stuff
289  *    such as only for boot CPU etc
290  */
291 
292 void setup_processor(void)
293 {
294 	char str[512];
295 	int cpu_id = smp_processor_id();
296 
297 	read_arc_build_cfg_regs();
298 	arc_init_IRQ();
299 
300 	printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
301 
302 	arc_mmu_init();
303 	arc_cache_init();
304 	arc_chk_ccms();
305 
306 	printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
307 
308 #ifdef CONFIG_SMP
309 	printk(arc_platform_smp_cpuinfo());
310 #endif
311 
312 	arc_chk_fpu();
313 }
314 
315 void __init setup_arch(char **cmdline_p)
316 {
317 	/* This also populates @boot_command_line from /bootargs */
318 	machine_desc = setup_machine_fdt(__dtb_start);
319 	if (!machine_desc)
320 		panic("Embedded DT invalid\n");
321 
322 	/* Append any u-boot provided cmdline */
323 #ifdef CONFIG_CMDLINE_UBOOT
324 	/* Add a whitespace seperator between the 2 cmdlines */
325 	strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
326 	strlcat(boot_command_line, command_line, COMMAND_LINE_SIZE);
327 #endif
328 
329 	/* Save unparsed command line copy for /proc/cmdline */
330 	*cmdline_p = boot_command_line;
331 
332 	/* To force early parsing of things like mem=xxx */
333 	parse_early_param();
334 
335 	/* Platform/board specific: e.g. early console registration */
336 	if (machine_desc->init_early)
337 		machine_desc->init_early();
338 
339 	setup_processor();
340 
341 #ifdef CONFIG_SMP
342 	smp_init_cpus();
343 #endif
344 
345 	setup_arch_memory();
346 
347 	/* copy flat DT out of .init and then unflatten it */
348 	unflatten_and_copy_device_tree();
349 
350 	/* Can be issue if someone passes cmd line arg "ro"
351 	 * But that is unlikely so keeping it as it is
352 	 */
353 	root_mountflags &= ~MS_RDONLY;
354 
355 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
356 	conswitchp = &dummy_con;
357 #endif
358 
359 	arc_unwind_init();
360 	arc_unwind_setup();
361 }
362 
363 static int __init customize_machine(void)
364 {
365 	/* Add platform devices */
366 	if (machine_desc->init_machine)
367 		machine_desc->init_machine();
368 
369 	return 0;
370 }
371 arch_initcall(customize_machine);
372 
373 static int __init init_late_machine(void)
374 {
375 	if (machine_desc->init_late)
376 		machine_desc->init_late();
377 
378 	return 0;
379 }
380 late_initcall(init_late_machine);
381 /*
382  *  Get CPU information for use by the procfs.
383  */
384 
385 #define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
386 #define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))
387 
388 static int show_cpuinfo(struct seq_file *m, void *v)
389 {
390 	char *str;
391 	int cpu_id = ptr_to_cpu(v);
392 
393 	str = (char *)__get_free_page(GFP_TEMPORARY);
394 	if (!str)
395 		goto done;
396 
397 	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
398 
399 	seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n",
400 		   loops_per_jiffy / (500000 / HZ),
401 		   (loops_per_jiffy / (5000 / HZ)) % 100);
402 
403 	seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
404 
405 	seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
406 
407 	seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
408 
409 #ifdef CONFIG_SMP
410 	seq_printf(m, arc_platform_smp_cpuinfo());
411 #endif
412 
413 	free_page((unsigned long)str);
414 done:
415 	seq_printf(m, "\n\n");
416 
417 	return 0;
418 }
419 
420 static void *c_start(struct seq_file *m, loff_t *pos)
421 {
422 	/*
423 	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
424 	 * However since NULL is also a valid cpu-id (0), we use a round-about
425 	 * way to pass it w/o having to kmalloc/free a 2 byte string.
426 	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
427 	 */
428 	return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
429 }
430 
431 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
432 {
433 	++*pos;
434 	return c_start(m, pos);
435 }
436 
437 static void c_stop(struct seq_file *m, void *v)
438 {
439 }
440 
441 const struct seq_operations cpuinfo_op = {
442 	.start	= c_start,
443 	.next	= c_next,
444 	.stop	= c_stop,
445 	.show	= show_cpuinfo
446 };
447 
448 static DEFINE_PER_CPU(struct cpu, cpu_topology);
449 
450 static int __init topology_init(void)
451 {
452 	int cpu;
453 
454 	for_each_present_cpu(cpu)
455 	    register_cpu(&per_cpu(cpu_topology, cpu), cpu);
456 
457 	return 0;
458 }
459 
460 subsys_initcall(topology_init);
461