kernel/arch/c6x/kernel/setup.c

   1 /*
   2  *  Port on Texas Instruments TMS320C6x architecture
   3  *
   4  *  Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated
   5  *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  */
  11 #include <linux/dma-mapping.h>
  12 #include <linux/memblock.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/bootmem.h>
  15 #include <linux/clkdev.h>
  16 #include <linux/initrd.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/of_fdt.h>
  20 #include <linux/string.h>
  21 #include <linux/errno.h>
  22 #include <linux/cache.h>
  23 #include <linux/delay.h>
  24 #include <linux/sched.h>
  25 #include <linux/clk.h>
  26 #include <linux/cpu.h>
  27 #include <linux/fs.h>
  28 #include <linux/of.h>
  29 #include <linux/console.h>
  30 #include <linux/screen_info.h>
  31
  32 #include <asm/sections.h>
  33 #include <asm/div64.h>
  34 #include <asm/setup.h>
  35 #include <asm/dscr.h>
  36 #include <asm/clock.h>
  37 #include <asm/soc.h>
  38 #include <asm/special_insns.h>
  39
  40 static const char *c6x_soc_name;
  41
  42 struct screen_info screen_info;
  43
  44 int c6x_num_cores;
  45 EXPORT_SYMBOL_GPL(c6x_num_cores);
  46
  47 unsigned int c6x_silicon_rev;
  48 EXPORT_SYMBOL_GPL(c6x_silicon_rev);
  49
  50 /*
  51  * Device status register. This holds information
  52  * about device configuration needed by some drivers.
  53  */
  54 unsigned int c6x_devstat;
  55 EXPORT_SYMBOL_GPL(c6x_devstat);
  56
  57 /*
  58  * Some SoCs have fuse registers holding a unique MAC
  59  * address. This is parsed out of the device tree with
  60  * the resulting MAC being held here.
  61  */
  62 unsigned char c6x_fuse_mac[6];
  63
  64 unsigned long memory_start;
  65 unsigned long memory_end;
  66 EXPORT_SYMBOL(memory_end);
  67
  68 unsigned long ram_start;
  69 unsigned long ram_end;
  70
  71 /* Uncached memory for DMA consistent use (memdma=) */
  72 static unsigned long dma_start __initdata;
  73 static unsigned long dma_size __initdata;
  74
  75 struct cpuinfo_c6x {
  76         const char *cpu_name;
  77         const char *cpu_voltage;
  78         const char *mmu;
  79         const char *fpu;
  80         char *cpu_rev;
  81         unsigned int core_id;
  82         char __cpu_rev[5];
  83 };
  84
  85 static DEFINE_PER_CPU(struct cpuinfo_c6x, cpu_data);
  86
  87 unsigned int ticks_per_ns_scaled;
  88 EXPORT_SYMBOL(ticks_per_ns_scaled);
  89
  90 unsigned int c6x_core_freq;
  91
  92 static void __init get_cpuinfo(void)
  93 {
  94         unsigned cpu_id, rev_id, csr;
  95         struct clk *coreclk = clk_get_sys(NULL, "core");
  96         unsigned long core_khz;
  97         u64 tmp;
  98         struct cpuinfo_c6x *p;
  99         struct device_node *node, *np;
 100
 101         p = &per_cpu(cpu_data, smp_processor_id());
 102
 103         if (!IS_ERR(coreclk))
 104                 c6x_core_freq = clk_get_rate(coreclk);
 105         else {
 106                 printk(KERN_WARNING
 107                        "Cannot find core clock frequency. Using 700MHz\n");
 108                 c6x_core_freq = 700000000;
 109         }
 110
 111         core_khz = c6x_core_freq / 1000;
 112
 113         tmp = (uint64_t)core_khz << C6X_NDELAY_SCALE;
 114         do_div(tmp, 1000000);
 115         ticks_per_ns_scaled = tmp;
 116
 117         csr = get_creg(CSR);
 118         cpu_id = csr >> 24;
 119         rev_id = (csr >> 16) & 0xff;
 120
 121         p->mmu = "none";
 122         p->fpu = "none";
 123         p->cpu_voltage = "unknown";
 124
 125         switch (cpu_id) {
 126         case 0:
 127                 p->cpu_name = "C67x";
 128                 p->fpu = "yes";
 129                 break;
 130         case 2:
 131                 p->cpu_name = "C62x";
 132                 break;
 133         case 8:
 134                 p->cpu_name = "C64x";
 135                 break;
 136         case 12:
 137                 p->cpu_name = "C64x";
 138                 break;
 139         case 16:
 140                 p->cpu_name = "C64x+";
 141                 p->cpu_voltage = "1.2";
 142                 break;
 143         case 21:
 144                 p->cpu_name = "C66X";
 145                 p->cpu_voltage = "1.2";
 146                 break;
 147         default:
 148                 p->cpu_name = "unknown";
 149                 break;
 150         }
 151
 152         if (cpu_id < 16) {
 153                 switch (rev_id) {
 154                 case 0x1:
 155                         if (cpu_id > 8) {
 156                                 p->cpu_rev = "DM640/DM641/DM642/DM643";
 157                                 p->cpu_voltage = "1.2 - 1.4";
 158                         } else {
 159                                 p->cpu_rev = "C6201";
 160                                 p->cpu_voltage = "2.5";
 161                         }
 162                         break;
 163                 case 0x2:
 164                         p->cpu_rev = "C6201B/C6202/C6211";
 165                         p->cpu_voltage = "1.8";
 166                         break;
 167                 case 0x3:
 168                         p->cpu_rev = "C6202B/C6203/C6204/C6205";
 169                         p->cpu_voltage = "1.5";
 170                         break;
 171                 case 0x201:
 172                         p->cpu_rev = "C6701 revision 0 (early CPU)";
 173                         p->cpu_voltage = "1.8";
 174                         break;
 175                 case 0x202:
 176                         p->cpu_rev = "C6701/C6711/C6712";
 177                         p->cpu_voltage = "1.8";
 178                         break;
 179                 case 0x801:
 180                         p->cpu_rev = "C64x";
 181                         p->cpu_voltage = "1.5";
 182                         break;
 183                 default:
 184                         p->cpu_rev = "unknown";
 185                 }
 186         } else {
 187                 p->cpu_rev = p->__cpu_rev;
 188                 snprintf(p->__cpu_rev, sizeof(p->__cpu_rev), "0x%x", cpu_id);
 189         }
 190
 191         p->core_id = get_coreid();
 192
 193         node = of_find_node_by_name(NULL, "cpus");
 194         if (node) {
 195                 for_each_child_of_node(node, np)
 196                         if (!strcmp("cpu", np->name))
 197                                 ++c6x_num_cores;
 198                 of_node_put(node);
 199         }
 200
 201         node = of_find_node_by_name(NULL, "soc");
 202         if (node) {
 203                 if (of_property_read_string(node, "model", &c6x_soc_name))
 204                         c6x_soc_name = "unknown";
 205                 of_node_put(node);
 206         } else
 207                 c6x_soc_name = "unknown";
 208
 209         printk(KERN_INFO "CPU%d: %s rev %s, %s volts, %uMHz\n",
 210                p->core_id, p->cpu_name, p->cpu_rev,
 211                p->cpu_voltage, c6x_core_freq / 1000000);
 212 }
 213
 214 /*
 215  * Early parsing of the command line
 216  */
 217 static u32 mem_size __initdata;
 218
 219 /* "mem=" parsing. */
 220 static int __init early_mem(char *p)
 221 {
 222         if (!p)
 223                 return -EINVAL;
 224
 225         mem_size = memparse(p, &p);
 226         /* don't remove all of memory when handling "mem={invalid}" */
 227         if (mem_size == 0)
 228                 return -EINVAL;
 229
 230         return 0;
 231 }
 232 early_param("mem", early_mem);
 233
 234 /* "memdma=<size>[@<address>]" parsing. */
 235 static int __init early_memdma(char *p)
 236 {
 237         if (!p)
 238                 return -EINVAL;
 239
 240         dma_size = memparse(p, &p);
 241         if (*p == '@')
 242                 dma_start = memparse(p, &p);
 243
 244         return 0;
 245 }
 246 early_param("memdma", early_memdma);
 247
 248 int __init c6x_add_memory(phys_addr_t start, unsigned long size)
 249 {
 250         static int ram_found __initdata;
 251
 252         /* We only handle one bank (the one with PAGE_OFFSET) for now */
 253         if (ram_found)
 254                 return -EINVAL;
 255
 256         if (start > PAGE_OFFSET || PAGE_OFFSET >= (start + size))
 257                 return 0;
 258
 259         ram_start = start;
 260         ram_end = start + size;
 261
 262         ram_found = 1;
 263         return 0;
 264 }
 265
 266 /*
 267  * Do early machine setup and device tree parsing. This is called very
 268  * early on the boot process.
 269  */
 270 notrace void __init machine_init(unsigned long dt_ptr)
 271 {
 272         void *dtb = __va(dt_ptr);
 273         void *fdt = _fdt_start;
 274
 275         /* interrupts must be masked */
 276         set_creg(IER, 2);
 277
 278         /*
 279          * Set the Interrupt Service Table (IST) to the beginning of the
 280          * vector table.
 281          */
 282         set_ist(_vectors_start);
 283
 284         lockdep_init();
 285
 286         /*
 287          * dtb is passed in from bootloader.
 288          * fdt is linked in blob.
 289          */
 290         if (dtb && dtb != fdt)
 291                 fdt = dtb;
 292
 293         /* Do some early initialization based on the flat device tree */
 294         early_init_dt_scan(fdt);
 295
 296         parse_early_param();
 297 }
 298
 299 void __init setup_arch(char **cmdline_p)
 300 {
 301         int bootmap_size;
 302         struct memblock_region *reg;
 303
 304         printk(KERN_INFO "Initializing kernel\n");
 305
 306         /* Initialize command line */
 307         *cmdline_p = boot_command_line;
 308
 309         memory_end = ram_end;
 310         memory_end &= ~(PAGE_SIZE - 1);
 311
 312         if (mem_size && (PAGE_OFFSET + PAGE_ALIGN(mem_size)) < memory_end)
 313                 memory_end = PAGE_OFFSET + PAGE_ALIGN(mem_size);
 314
 315         /* add block that this kernel can use */
 316         memblock_add(PAGE_OFFSET, memory_end - PAGE_OFFSET);
 317
 318         /* reserve kernel text/data/bss */
 319         memblock_reserve(PAGE_OFFSET,
 320                          PAGE_ALIGN((unsigned long)&_end - PAGE_OFFSET));
 321
 322         if (dma_size) {
 323                 /* align to cacheability granularity */
 324                 dma_size = CACHE_REGION_END(dma_size);
 325
 326                 if (!dma_start)
 327                         dma_start = memory_end - dma_size;
 328
 329                 /* align to cacheability granularity */
 330                 dma_start = CACHE_REGION_START(dma_start);
 331
 332                 /* reserve DMA memory taken from kernel memory */
 333                 if (memblock_is_region_memory(dma_start, dma_size))
 334                         memblock_reserve(dma_start, dma_size);
 335         }
 336
 337         memory_start = PAGE_ALIGN((unsigned int) &_end);
 338
 339         printk(KERN_INFO "Memory Start=%08lx, Memory End=%08lx\n",
 340                memory_start, memory_end);
 341
 342 #ifdef CONFIG_BLK_DEV_INITRD
 343         /*
 344          * Reserve initrd memory if in kernel memory.
 345          */
 346         if (initrd_start < initrd_end)
 347                 if (memblock_is_region_memory(initrd_start,
 348                                               initrd_end - initrd_start))
 349                         memblock_reserve(initrd_start,
 350                                          initrd_end - initrd_start);
 351 #endif
 352
 353         init_mm.start_code = (unsigned long) &_stext;
 354         init_mm.end_code   = (unsigned long) &_etext;
 355         init_mm.end_data   = memory_start;
 356         init_mm.brk        = memory_start;
 357
 358         /*
 359          * Give all the memory to the bootmap allocator,  tell it to put the
 360          * boot mem_map at the start of memory
 361          */
 362         bootmap_size = init_bootmem_node(NODE_DATA(0),
 363                                          memory_start >> PAGE_SHIFT,
 364                                          PAGE_OFFSET >> PAGE_SHIFT,
 365                                          memory_end >> PAGE_SHIFT);
 366         memblock_reserve(memory_start, bootmap_size);
 367
 368         unflatten_device_tree();
 369
 370         c6x_cache_init();
 371
 372         /* Set the whole external memory as non-cacheable */
 373         disable_caching(ram_start, ram_end - 1);
 374
 375         /* Set caching of external RAM used by Linux */
 376         for_each_memblock(memory, reg)
 377                 enable_caching(CACHE_REGION_START(reg->base),
 378                                CACHE_REGION_START(reg->base + reg->size - 1));
 379
 380 #ifdef CONFIG_BLK_DEV_INITRD
 381         /*
 382          * Enable caching for initrd which falls outside kernel memory.
 383          */
 384         if (initrd_start < initrd_end) {
 385                 if (!memblock_is_region_memory(initrd_start,
 386                                                initrd_end - initrd_start))
 387                         enable_caching(CACHE_REGION_START(initrd_start),
 388                                        CACHE_REGION_START(initrd_end - 1));
 389         }
 390 #endif
 391
 392         /*
 393          * Disable caching for dma coherent memory taken from kernel memory.
 394          */
 395         if (dma_size && memblock_is_region_memory(dma_start, dma_size))
 396                 disable_caching(dma_start,
 397                                 CACHE_REGION_START(dma_start + dma_size - 1));
 398
 399         /* Initialize the coherent memory allocator */
 400         coherent_mem_init(dma_start, dma_size);
 401
 402         /*
 403          * Free all memory as a starting point.
 404          */
 405         free_bootmem(PAGE_OFFSET, memory_end - PAGE_OFFSET);
 406
 407         /*
 408          * Then reserve memory which is already being used.
 409          */
 410         for_each_memblock(reserved, reg) {
 411                 pr_debug("reserved - 0x%08x-0x%08x\n",
 412                          (u32) reg->base, (u32) reg->size);
 413                 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
 414         }
 415
 416         max_low_pfn = PFN_DOWN(memory_end);
 417         min_low_pfn = PFN_UP(memory_start);
 418         max_mapnr = max_low_pfn - min_low_pfn;
 419
 420         /* Get kmalloc into gear */
 421         paging_init();
 422
 423         /*
 424          * Probe for Device State Configuration Registers.
 425          * We have to do this early in case timer needs to be enabled
 426          * through DSCR.
 427          */
 428         dscr_probe();
 429
 430         /* We do this early for timer and core clock frequency */
 431         c64x_setup_clocks();
 432
 433         /* Get CPU info */
 434         get_cpuinfo();
 435
 436 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
 437         conswitchp = &dummy_con;
 438 #endif
 439 }
 440
 441 #define cpu_to_ptr(n) ((void *)((long)(n)+1))
 442 #define ptr_to_cpu(p) ((long)(p) - 1)
 443
 444 static int show_cpuinfo(struct seq_file *m, void *v)
 445 {
 446         int n = ptr_to_cpu(v);
 447         struct cpuinfo_c6x *p = &per_cpu(cpu_data, n);
 448
 449         if (n == 0) {
 450                 seq_printf(m,
 451                            "soc\t\t: %s\n"
 452                            "soc revision\t: 0x%x\n"
 453                            "soc cores\t: %d\n",
 454                            c6x_soc_name, c6x_silicon_rev, c6x_num_cores);
 455         }
 456
 457         seq_printf(m,
 458                    "\n"
 459                    "processor\t: %d\n"
 460                    "cpu\t\t: %s\n"
 461                    "core revision\t: %s\n"
 462                    "core voltage\t: %s\n"
 463                    "core id\t\t: %d\n"
 464                    "mmu\t\t: %s\n"
 465                    "fpu\t\t: %s\n"
 466                    "cpu MHz\t\t: %u\n"
 467                    "bogomips\t: %lu.%02lu\n\n",
 468                    n,
 469                    p->cpu_name, p->cpu_rev, p->cpu_voltage,
 470                    p->core_id, p->mmu, p->fpu,
 471                    (c6x_core_freq + 500000) / 1000000,
 472                    (loops_per_jiffy/(500000/HZ)),
 473                    (loops_per_jiffy/(5000/HZ))%100);
 474
 475         return 0;
 476 }
 477
 478 static void *c_start(struct seq_file *m, loff_t *pos)
 479 {
 480         return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
 481 }
 482 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 483 {
 484         ++*pos;
 485         return NULL;
 486 }
 487 static void c_stop(struct seq_file *m, void *v)
 488 {
 489 }
 490
 491 const struct seq_operations cpuinfo_op = {
 492         c_start,
 493         c_stop,
 494         c_next,
 495         show_cpuinfo
 496 };
 497
 498 static struct cpu cpu_devices[NR_CPUS];
 499
 500 static int __init topology_init(void)
 501 {
 502         int i;
 503
 504         for_each_present_cpu(i)
 505                 register_cpu(&cpu_devices[i], i);
 506
 507         return 0;
 508 }
 509
 510 subsys_initcall(topology_init);