kernel/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 /* 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         READ_BCR(ARC_REG_RTT_BCR, bcr);
 124         cpu->extn.rtt = bcr.ver ? 1 : 0;
 125
 126         cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt;
 127 }
 128
 129 static const struct cpuinfo_data arc_cpu_tbl[] = {
 130         { {0x20, "ARC 600"      }, 0x2F},
 131         { {0x30, "ARC 700"      }, 0x33},
 132         { {0x34, "ARC 700 R4.10"}, 0x34},
 133         { {0x35, "ARC 700 R4.11"}, 0x35},
 134         { {0x00, NULL           } }
 135 };
 136
 137 #define IS_AVAIL1(v, str)       ((v) ? str : "")
 138 #define IS_USED(cfg)            (IS_ENABLED(cfg) ? "" : "(not used) ")
 139 #define IS_AVAIL2(v, str, cfg)  IS_AVAIL1(v, str), IS_AVAIL1(v, IS_USED(cfg))
 140
 141 static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len)
 142 {
 143         struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
 144         struct bcr_identity *core = &cpu->core;
 145         const struct cpuinfo_data *tbl;
 146         char *isa_nm;
 147         int i, be, atomic;
 148         int n = 0;
 149
 150         FIX_PTR(cpu);
 151
 152         {
 153                 isa_nm = "ARCompact";
 154                 be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
 155
 156                 atomic = cpu->isa.atomic1;
 157                 if (!cpu->isa.ver)      /* ISA BCR absent, use Kconfig info */
 158                         atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
 159         }
 160
 161         n += scnprintf(buf + n, len - n,
 162                        "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
 163                        core->family, core->cpu_id, core->chip_id);
 164
 165         for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) {
 166                 if ((core->family >= tbl->info.id) &&
 167                     (core->family <= tbl->up_range)) {
 168                         n += scnprintf(buf + n, len - n,
 169                                        "processor [%d]\t: %s (%s ISA) %s\n",
 170                                        cpu_id, tbl->info.str, isa_nm,
 171                                        IS_AVAIL1(be, "[Big-Endian]"));
 172                         break;
 173                 }
 174         }
 175
 176         if (tbl->info.id == 0)
 177                 n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n");
 178
 179         n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n",
 180                        (unsigned int)(arc_get_core_freq() / 1000000),
 181                        (unsigned int)(arc_get_core_freq() / 10000) % 100);
 182
 183         n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
 184                        IS_AVAIL1(cpu->timers.t0, "Timer0 "),
 185                        IS_AVAIL1(cpu->timers.t1, "Timer1 "),
 186                        IS_AVAIL2(cpu->timers.rtsc, "64-bit RTSC ", CONFIG_ARC_HAS_RTSC));
 187
 188         n += i = scnprintf(buf + n, len - n, "%s%s",
 189                            IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC));
 190
 191         if (i)
 192                 n += scnprintf(buf + n, len - n, "\n\t\t: ");
 193
 194         n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n",
 195                        IS_AVAIL1(cpu->extn_mpy.ver, "mpy "),
 196                        IS_AVAIL1(cpu->extn.norm, "norm "),
 197                        IS_AVAIL1(cpu->extn.barrel, "barrel-shift "),
 198                        IS_AVAIL1(cpu->extn.swap, "swap "),
 199                        IS_AVAIL1(cpu->extn.minmax, "minmax "),
 200                        IS_AVAIL1(cpu->extn.crc, "crc "),
 201                        IS_AVAIL2(1, "swape", CONFIG_ARC_HAS_SWAPE));
 202
 203         if (cpu->bpu.ver)
 204                 n += scnprintf(buf + n, len - n,
 205                               "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
 206                               IS_AVAIL1(cpu->bpu.full, "full"),
 207                               IS_AVAIL1(!cpu->bpu.full, "partial"),
 208                               cpu->bpu.num_cache, cpu->bpu.num_pred);
 209
 210         return buf;
 211 }
 212
 213 static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
 214 {
 215         int n = 0;
 216         struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id];
 217
 218         FIX_PTR(cpu);
 219
 220         n += scnprintf(buf + n, len - n,
 221                        "Vector Table\t: %#x\nUncached Base\t: %#x\n",
 222                        cpu->vec_base, cpu->uncached_base);
 223
 224         if (cpu->extn.fpu_sp || cpu->extn.fpu_dp)
 225                 n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
 226                                IS_AVAIL1(cpu->extn.fpu_sp, "SP "),
 227                                IS_AVAIL1(cpu->extn.fpu_dp, "DP "));
 228
 229         if (cpu->extn.debug)
 230                 n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n",
 231                                IS_AVAIL1(cpu->extn.ap, "ActionPoint "),
 232                                IS_AVAIL1(cpu->extn.smart, "smaRT "),
 233                                IS_AVAIL1(cpu->extn.rtt, "RTT "));
 234
 235         if (cpu->dccm.sz || cpu->iccm.sz)
 236                 n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n",
 237                                cpu->dccm.base_addr, TO_KB(cpu->dccm.sz),
 238                                cpu->iccm.base_addr, TO_KB(cpu->iccm.sz));
 239
 240         n += scnprintf(buf + n, len - n,
 241                        "OS ABI [v3]\t: no-legacy-syscalls\n");
 242
 243         return buf;
 244 }
 245
 246 static void arc_chk_core_config(void)
 247 {
 248         struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
 249         int fpu_enabled;
 250
 251         if (!cpu->timers.t0)
 252                 panic("Timer0 is not present!\n");
 253
 254         if (!cpu->timers.t1)
 255                 panic("Timer1 is not present!\n");
 256
 257         if (IS_ENABLED(CONFIG_ARC_HAS_RTSC) && !cpu->timers.rtsc)
 258                 panic("RTSC is not present\n");
 259
 260 #ifdef CONFIG_ARC_HAS_DCCM
 261         /*
 262          * DCCM can be arbit placed in hardware.
 263          * Make sure it's placement/sz matches what Linux is built with
 264          */
 265         if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr)
 266                 panic("Linux built with incorrect DCCM Base address\n");
 267
 268         if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz)
 269                 panic("Linux built with incorrect DCCM Size\n");
 270 #endif
 271
 272 #ifdef CONFIG_ARC_HAS_ICCM
 273         if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz)
 274                 panic("Linux built with incorrect ICCM Size\n");
 275 #endif
 276
 277         /*
 278          * FP hardware/software config sanity
 279          * -If hardware contains DPFP, kernel needs to save/restore FPU state
 280          * -If not, it will crash trying to save/restore the non-existant regs
 281          *
 282          * (only DPDP checked since SP has no arch visible regs)
 283          */
 284         fpu_enabled = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
 285
 286         if (cpu->extn.fpu_dp && !fpu_enabled)
 287                 pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n");
 288         else if (!cpu->extn.fpu_dp && fpu_enabled)
 289                 panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n");
 290 }
 291
 292 /*
 293  * Initialize and setup the processor core
 294  * This is called by all the CPUs thus should not do special case stuff
 295  *    such as only for boot CPU etc
 296  */
 297
 298 void setup_processor(void)
 299 {
 300         char str[512];
 301         int cpu_id = smp_processor_id();
 302
 303         read_arc_build_cfg_regs();
 304         arc_init_IRQ();
 305
 306         printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str)));
 307
 308         arc_mmu_init();
 309         arc_cache_init();
 310
 311         printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str)));
 312         printk(arc_platform_smp_cpuinfo());
 313
 314         arc_chk_core_config();
 315 }
 316
 317 static inline int is_kernel(unsigned long addr)
 318 {
 319         if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
 320                 return 1;
 321         return 0;
 322 }
 323
 324 void __init setup_arch(char **cmdline_p)
 325 {
 326         /* make sure that uboot passed pointer to cmdline/dtb is valid */
 327         if (uboot_tag && is_kernel((unsigned long)uboot_arg))
 328                 panic("Invalid uboot arg\n");
 329
 330         /* See if u-boot passed an external Device Tree blob */
 331         machine_desc = setup_machine_fdt(uboot_arg);    /* uboot_tag == 2 */
 332         if (!machine_desc) {
 333                 /* No, so try the embedded one */
 334                 machine_desc = setup_machine_fdt(__dtb_start);
 335                 if (!machine_desc)
 336                         panic("Embedded DT invalid\n");
 337
 338                 /*
 339                  * If we are here, it is established that @uboot_arg didn't
 340                  * point to DT blob. Instead if u-boot says it is cmdline,
 341                  * Appent to embedded DT cmdline.
 342                  * setup_machine_fdt() would have populated @boot_command_line
 343                  */
 344                 if (uboot_tag == 1) {
 345                         /* Ensure a whitespace between the 2 cmdlines */
 346                         strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
 347                         strlcat(boot_command_line, uboot_arg,
 348                                 COMMAND_LINE_SIZE);
 349                 }
 350         }
 351
 352         /* Save unparsed command line copy for /proc/cmdline */
 353         *cmdline_p = boot_command_line;
 354
 355         /* To force early parsing of things like mem=xxx */
 356         parse_early_param();
 357
 358         /* Platform/board specific: e.g. early console registration */
 359         if (machine_desc->init_early)
 360                 machine_desc->init_early();
 361
 362         setup_processor();
 363         smp_init_cpus();
 364         setup_arch_memory();
 365
 366         /* copy flat DT out of .init and then unflatten it */
 367         unflatten_and_copy_device_tree();
 368
 369         /* Can be issue if someone passes cmd line arg "ro"
 370          * But that is unlikely so keeping it as it is
 371          */
 372         root_mountflags &= ~MS_RDONLY;
 373
 374 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
 375         conswitchp = &dummy_con;
 376 #endif
 377
 378         arc_unwind_init();
 379         arc_unwind_setup();
 380 }
 381
 382 static int __init customize_machine(void)
 383 {
 384         of_clk_init(NULL);
 385         /*
 386          * Traverses flattened DeviceTree - registering platform devices
 387          * (if any) complete with their resources
 388          */
 389         of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 390
 391         if (machine_desc->init_machine)
 392                 machine_desc->init_machine();
 393
 394         return 0;
 395 }
 396 arch_initcall(customize_machine);
 397
 398 static int __init init_late_machine(void)
 399 {
 400         if (machine_desc->init_late)
 401                 machine_desc->init_late();
 402
 403         return 0;
 404 }
 405 late_initcall(init_late_machine);
 406 /*
 407  *  Get CPU information for use by the procfs.
 408  */
 409
 410 #define cpu_to_ptr(c)   ((void *)(0xFFFF0000 | (unsigned int)(c)))
 411 #define ptr_to_cpu(p)   (~0xFFFF0000UL & (unsigned int)(p))
 412
 413 static int show_cpuinfo(struct seq_file *m, void *v)
 414 {
 415         char *str;
 416         int cpu_id = ptr_to_cpu(v);
 417
 418         if (!cpu_online(cpu_id)) {
 419                 seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
 420                 goto done;
 421         }
 422
 423         str = (char *)__get_free_page(GFP_TEMPORARY);
 424         if (!str)
 425                 goto done;
 426
 427         seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE));
 428
 429         seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
 430                    loops_per_jiffy / (500000 / HZ),
 431                    (loops_per_jiffy / (5000 / HZ)) % 100);
 432
 433         seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE));
 434         seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE));
 435         seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE));
 436         seq_printf(m, arc_platform_smp_cpuinfo());
 437
 438         free_page((unsigned long)str);
 439 done:
 440         seq_printf(m, "\n");
 441
 442         return 0;
 443 }
 444
 445 static void *c_start(struct seq_file *m, loff_t *pos)
 446 {
 447         /*
 448          * Callback returns cpu-id to iterator for show routine, NULL to stop.
 449          * However since NULL is also a valid cpu-id (0), we use a round-about
 450          * way to pass it w/o having to kmalloc/free a 2 byte string.
 451          * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
 452          */
 453         return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL;
 454 }
 455
 456 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 457 {
 458         ++*pos;
 459         return c_start(m, pos);
 460 }
 461
 462 static void c_stop(struct seq_file *m, void *v)
 463 {
 464 }
 465
 466 const struct seq_operations cpuinfo_op = {
 467         .start  = c_start,
 468         .next   = c_next,
 469         .stop   = c_stop,
 470         .show   = show_cpuinfo
 471 };
 472
 473 static DEFINE_PER_CPU(struct cpu, cpu_topology);
 474
 475 static int __init topology_init(void)
 476 {
 477         int cpu;
 478
 479         for_each_present_cpu(cpu)
 480             register_cpu(&per_cpu(cpu_topology, cpu), cpu);
 481
 482         return 0;
 483 }
 484
 485 subsys_initcall(topology_init);