ARCv2: Check for LL-SC livelock only if LLSC is enabled
[cascardo/linux.git] / arch / arc / kernel / setup.c
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_timer timer;
49         struct bcr_generic bcr;
50         struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
51         unsigned long perip_space;
52         FIX_PTR(cpu);
53
54         READ_BCR(AUX_IDENTITY, cpu->core);
55         READ_BCR(ARC_REG_ISA_CFG_BCR, cpu->isa);
56
57         READ_BCR(ARC_REG_TIMERS_BCR, timer);
58         cpu->extn.timer0 = timer.t0;
59         cpu->extn.timer1 = timer.t1;
60         cpu->extn.rtc = timer.rtc;
61
62         cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
63
64         READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space);
65         if (uncached_space.ver < 3)
66                 perip_space = uncached_space.start << 24;
67         else
68                 perip_space = read_aux_reg(AUX_NON_VOL) & 0xF0000000;
69
70         BUG_ON(perip_space != ARC_UNCACHED_ADDR_SPACE);
71
72         READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy);
73
74         cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */
75         cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */
76         cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0;        /* 1,3 */
77         cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0;
78         cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */
79
80         /* Note that we read the CCM BCRs independent of kernel config
81          * This is to catch the cases where user doesn't know that
82          * CCMs are present in hardware build
83          */
84         {
85                 struct bcr_iccm iccm;
86                 struct bcr_dccm dccm;
87                 struct bcr_dccm_base dccm_base;
88                 unsigned int bcr_32bit_val;
89
90                 bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR);
91                 if (bcr_32bit_val) {
92                         iccm = *((struct bcr_iccm *)&bcr_32bit_val);
93                         cpu->iccm.base_addr = iccm.base << 16;
94                         cpu->iccm.sz = 0x2000 << (iccm.sz - 1);
95                 }
96
97                 bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR);
98                 if (bcr_32bit_val) {
99                         dccm = *((struct bcr_dccm *)&bcr_32bit_val);
100                         cpu->dccm.sz = 0x800 << (dccm.sz);
101
102                         READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base);
103                         cpu->dccm.base_addr = dccm_base.addr << 8;
104                 }
105         }
106
107         READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem);
108
109         read_decode_mmu_bcr();
110         read_decode_cache_bcr();
111
112         if (is_isa_arcompact()) {
113                 struct bcr_fp_arcompact sp, dp;
114                 struct bcr_bpu_arcompact bpu;
115
116                 READ_BCR(ARC_REG_FP_BCR, sp);
117                 READ_BCR(ARC_REG_DPFP_BCR, dp);
118                 cpu->extn.fpu_sp = sp.ver ? 1 : 0;
119                 cpu->extn.fpu_dp = dp.ver ? 1 : 0;
120
121                 READ_BCR(ARC_REG_BPU_BCR, bpu);
122                 cpu->bpu.ver = bpu.ver;
123                 cpu->bpu.full = bpu.fam ? 1 : 0;
124                 if (bpu.ent) {
125                         cpu->bpu.num_cache = 256 << (bpu.ent - 1);
126                         cpu->bpu.num_pred = 256 << (bpu.ent - 1);
127                 }
128         } else {
129                 struct bcr_fp_arcv2 spdp;
130                 struct bcr_bpu_arcv2 bpu;
131
132                 READ_BCR(ARC_REG_FP_V2_BCR, spdp);
133                 cpu->extn.fpu_sp = spdp.sp ? 1 : 0;
134                 cpu->extn.fpu_dp = spdp.dp ? 1 : 0;
135
136                 READ_BCR(ARC_REG_BPU_BCR, bpu);
137                 cpu->bpu.ver = bpu.ver;
138                 cpu->bpu.full = bpu.ft;
139                 cpu->bpu.num_cache = 256 << bpu.bce;
140                 cpu->bpu.num_pred = 2048 << bpu.pte;
141         }
142
143         READ_BCR(ARC_REG_AP_BCR, bcr);
144         cpu->extn.ap = bcr.ver ? 1 : 0;
145
146         READ_BCR(ARC_REG_SMART_BCR, bcr);
147         cpu->extn.smart = bcr.ver ? 1 : 0;
148
149         READ_BCR(ARC_REG_RTT_BCR, bcr);
150         cpu->extn.rtt = bcr.ver ? 1 : 0;
151
152         cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
153 }
154
155 static const struct cpuinfo_data arc_cpu_tbl[] = {
156 #ifdef CONFIG_ISA_ARCOMPACT
157         { {0x20, "ARC 600"      }, 0x2F},
158         { {0x30, "ARC 700"      }, 0x33},
159         { {0x34, "ARC 700 R4.10"}, 0x34},
160         { {0x35, "ARC 700 R4.11"}, 0x35},
161 #else
162         { {0x50, "ARC HS38 R2.0"}, 0x51},
163         { {0x52, "ARC HS38 R2.1"}, 0x52},
164 #endif
165         { {0x00, NULL           } }
166 };
167
168
169 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
170 {
171         struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
172         struct bcr_identity *core = &cpu->core;
173         const struct cpuinfo_data *tbl;
174         char *isa_nm;
175         int i, be, atomic;
176         int n = 0;
177
178         FIX_PTR(cpu);
179
180         if (is_isa_arcompact()) {
181                 isa_nm = "ARCompact";
182                 be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
183
184                 atomic = cpu->isa.atomic1;
185                 if (!cpu->isa.ver)      /* ISA BCR absent, use Kconfig info */
186                         atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
187         } else {
188                 isa_nm = "ARCv2";
189                 be = cpu->isa.be;
190                 atomic = cpu->isa.atomic;
191         }
192
193         n += scnprintf(buf + n, len - n,
194                        "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
195                        core->family, core->cpu_id, core->chip_id);
196
197         for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
198                 if ((core->family >= tbl->info.id) &&
199                     (core->family <= tbl->up_range)) {
200                         n += scnprintf(buf + n, len - n,
201                                        "processor [%d]\t: %s (%s ISA) %s\n",
202                                        cpu_id, tbl->info.str, isa_nm,
203                                        IS_AVAIL1(be, "[Big-Endian]"));
204                         break;
205                 }
206         }
207
208         if (tbl->info.id == 0)
209                 n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
210
211         n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
212                        (unsigned int)(arc_get_core_freq() / 1000000),
213                        (unsigned int)(arc_get_core_freq() / 10000) % 100);
214
215         n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
216                        IS_AVAIL1(cpu->extn.timer0, "Timer0 "),
217                        IS_AVAIL1(cpu->extn.timer1, "Timer1 "),
218                        IS_AVAIL2(cpu->extn.rtc, "Local-64-bit-Ctr ",
219                                  CONFIG_ARC_HAS_RTC));
220
221         n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s",
222                            IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
223                            IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
224                            IS_AVAIL1(cpu->isa.unalign, "unalign (not used)"));
225
226         if (i)
227                 n += scnprintf(buf + n, len - n, "\n\t\t: ");
228
229         if (cpu->extn_mpy.ver) {
230                 if (cpu->extn_mpy.ver <= 0x2) { /* ARCompact */
231                         n += scnprintf(buf + n, len - n, "mpy ");
232                 } else {
233                         int opt = 2;    /* stock MPY/MPYH */
234
235                         if (cpu->extn_mpy.dsp)  /* OPT 7-9 */
236                                 opt = cpu->extn_mpy.dsp + 6;
237
238                         n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt);
239                 }
240                 n += scnprintf(buf + n, len - n, "%s",
241                                IS_USED_CFG(CONFIG_ARC_HAS_HW_MPY));
242         }
243
244         n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
245                        IS_AVAIL1(cpu->isa.div_rem, "div_rem "),
246                        IS_AVAIL1(cpu->extn.norm, "norm "),
247                        IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
248                        IS_AVAIL1(cpu->extn.swap, "swap "),
249                        IS_AVAIL1(cpu->extn.minmax, "minmax "),
250                        IS_AVAIL1(cpu->extn.crc, "crc "),
251                        IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
252
253         if (cpu->bpu.ver)
254                 n += scnprintf(buf + n, len - n,
255                               "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
256                               IS_AVAIL1(cpu->bpu.full, "full"),
257                               IS_AVAIL1(!cpu->bpu.full, "partial"),
258                               cpu->bpu.num_cache, cpu->bpu.num_pred);
259
260         return buf;
261 }
262
263 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
264 {
265         int n = 0;
266         struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
267
268         FIX_PTR(cpu);
269
270         n += scnprintf(buf + n, len - n,
271                        "Vector Table\t: %#x\nUncached Base\t: %#x\n",
272                        cpu->vec_base, ARC_UNCACHED_ADDR_SPACE);
273
274         if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
275                 n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
276                                IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
277                                IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
278
279         if (cpu->extn.debug)
280                 n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
281                                IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
282                                IS_AVAIL1(cpu->extn.smart, "smaRT "),
283                                IS_AVAIL1(cpu->extn.rtt, "RTT "));
284
285         if (cpu->dccm.sz || cpu->iccm.sz)
286                 n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
287                                cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
288                                cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
289
290         n += scnprintf(buf + n, len - n,
291                        "OS ABI [v3]\t: no-legacy-syscalls\n");
292
293         return buf;
294 }
295
296 static void arc_chk_core_config(void)
297 {
298         struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
299         int fpu_enabled;
300
301         if (!cpu->extn.timer0)
302                 panic("Timer0 is not present!\n");
303
304         if (!cpu->extn.timer1)
305                 panic("Timer1 is not present!\n");
306
307         if (IS_ENABLED(CONFIG_ARC_HAS_RTC) && !cpu->extn.rtc)
308                 panic("RTC is not present\n");
309
310 #ifdef CONFIG_ARC_HAS_DCCM
311         /*
312          * DCCM can be arbit placed in hardware.
313          * Make sure it's placement/sz matches what Linux is built with
314          */
315         if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
316                 panic("Linux built with incorrect DCCM Base address\n");
317
318         if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
319                 panic("Linux built with incorrect DCCM Size\n");
320 #endif
321
322 #ifdef CONFIG_ARC_HAS_ICCM
323         if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
324                 panic("Linux built with incorrect ICCM Size\n");
325 #endif
326
327         /*
328          * FP hardware/software config sanity
329          * -If hardware contains DPFP, kernel needs to save/restore FPU state
330          * -If not, it will crash trying to save/restore the non-existant regs
331          *
332          * (only DPDP checked since SP has no arch visible regs)
333          */
334         fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
335
336         if (cpu->extn.fpu_dp && !fpu_enabled)
337                 pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
338         else if (!cpu->extn.fpu_dp && fpu_enabled)
339                 panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
340
341         if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic &&
342             IS_ENABLED(CONFIG_ARC_HAS_LLSC) &&
343             !IS_ENABLED(CONFIG_ARC_STAR_9000923308))
344                 panic("llock/scond livelock workaround missing\n");
345 }
346
347 /*
348  * Initialize and setup the processor core
349  * This is called by all the CPUs thus should not do special case stuff
350  *    such as only for boot CPU etc
351  */
352
353 void setup_processor(void)
354 {
355         char str[512];
356         int cpu_id = smp_processor_id();
357
358         read_arc_build_cfg_regs();
359         arc_init_IRQ();
360
361         printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
362
363         arc_mmu_init();
364         arc_cache_init();
365
366         printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
367         printk(arc_platform_smp_cpuinfo());
368
369         arc_chk_core_config();
370 }
371
372 static inline int is_kernel(unsigned long addr)
373 {
374         if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
375                 return 1;
376         return 0;
377 }
378
379 void __init setup_arch(char **cmdline_p)
380 {
381 #ifdef CONFIG_ARC_UBOOT_SUPPORT
382         /* make sure that uboot passed pointer to cmdline/dtb is valid */
383         if (uboot_tag && is_kernel((unsigned long)uboot_arg))
384                 panic("Invalid uboot arg\n");
385
386         /* See if u-boot passed an external Device Tree blob */
387         machine_desc = setup_machine_fdt(uboot_arg);    /* uboot_tag == 2 */
388         if (!machine_desc)
389 #endif
390         {
391                 /* No, so try the embedded one */
392                 machine_desc = setup_machine_fdt(__dtb_start);
393                 if (!machine_desc)
394                         panic("Embedded DT invalid\n");
395
396                 /*
397                  * If we are here, it is established that @uboot_arg didn't
398                  * point to DT blob. Instead if u-boot says it is cmdline,
399                  * Appent to embedded DT cmdline.
400                  * setup_machine_fdt() would have populated @boot_command_line
401                  */
402                 if (uboot_tag == 1) {
403                         /* Ensure a whitespace between the 2 cmdlines */
404                         strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
405                         strlcat(boot_command_line, uboot_arg,
406                                 COMMAND_LINE_SIZE);
407                 }
408         }
409
410         /* Save unparsed command line copy for /proc/cmdline */
411         *cmdline_p = boot_command_line;
412
413         /* To force early parsing of things like mem=xxx */
414         parse_early_param();
415
416         /* Platform/board specific: e.g. early console registration */
417         if (machine_desc->init_early)
418                 machine_desc->init_early();
419
420         smp_init_cpus();
421
422         setup_processor();
423         setup_arch_memory();
424
425         /* copy flat DT out of .init and then unflatten it */
426         unflatten_and_copy_device_tree();
427
428         /* Can be issue if someone passes cmd line arg "ro"
429          * But that is unlikely so keeping it as it is
430          */
431         root_mountflags &= ~MS_RDONLY;
432
433 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
434         conswitchp = &dummy_con;
435 #endif
436
437         arc_unwind_init();
438 }
439
440 static int __init customize_machine(void)
441 {
442         of_clk_init(NULL);
443         /*
444          * Traverses flattened DeviceTree - registering platform devices
445          * (if any) complete with their resources
446          */
447         of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
448
449         if (machine_desc->init_machine)
450                 machine_desc->init_machine();
451
452         return 0;
453 }
454 arch_initcall(customize_machine);
455
456 static int __init init_late_machine(void)
457 {
458         if (machine_desc->init_late)
459                 machine_desc->init_late();
460
461         return 0;
462 }
463 late_initcall(init_late_machine);
464 /*
465  *  Get CPU information for use by the procfs.
466  */
467
468 #define cpu_to_ptr(c)   ((void *)(0xFFFF0000 | (unsigned int)(c)))
469 #define ptr_to_cpu(p)   (~0xFFFF0000UL & (unsigned int)(p))
470
471 static int show_cpuinfo(struct seq_file *m, void *v)
472 {
473         char *str;
474         int cpu_id = ptr_to_cpu(v);
475
476         if (!cpu_online(cpu_id)) {
477                 seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
478                 goto done;
479         }
480
481         str = (char *)__get_free_page(GFP_TEMPORARY);
482         if (!str)
483                 goto done;
484
485         seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
486
487         seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
488                    loops_per_jiffy / (500000 / HZ),
489                    (loops_per_jiffy / (5000 / HZ)) % 100);
490
491         seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
492         seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
493         seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
494         seq_printf(m, arc_platform_smp_cpuinfo());
495
496         free_page((unsigned long)str);
497 done:
498         seq_printf(m, "\n");
499
500         return 0;
501 }
502
503 static void *c_start(struct seq_file *m, loff_t *pos)
504 {
505         /*
506          * Callback returns cpu-id to iterator for show routine, NULL to stop.
507          * However since NULL is also a valid cpu-id (0), we use a round-about
508          * way to pass it w/o having to kmalloc/free a 2 byte string.
509          * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
510          */
511         return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
512 }
513
514 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
515 {
516         ++*pos;
517         return c_start(m, pos);
518 }
519
520 static void c_stop(struct seq_file *m, void *v)
521 {
522 }
523
524 const struct seq_operations cpuinfo_op = {
525         .start  = c_start,
526         .next   = c_next,
527         .stop   = c_stop,
528         .show   = show_cpuinfo
529 };
530
531 static DEFINE_PER_CPU(struct cpu, cpu_topology);
532
533 static int __init topology_init(void)
534 {
535         int cpu;
536
537         for_each_present_cpu(cpu)
538             register_cpu(&per_cpu(cpu_topology, cpu), cpu);
539
540         return 0;
541 }
542
543 subsys_initcall(topology_init);