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