arch/openrisc/kernel/setup.c

   1 /*
   2  * OpenRISC setup.c
   3  *
   4  * Linux architectural port borrowing liberally from similar works of
   5  * others.  All original copyrights apply as per the original source
   6  * declaration.
   7  *
   8  * Modifications for the OpenRISC architecture:
   9  * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
  10  * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
  11  *
  12  *      This program is free software; you can redistribute it and/or
  13  *      modify it under the terms of the GNU General Public License
  14  *      as published by the Free Software Foundation; either version
  15  *      2 of the License, or (at your option) any later version.
  16  *
  17  * This file handles the architecture-dependent parts of initialization
  18  */
  19
  20 #include <linux/errno.h>
  21 #include <linux/sched.h>
  22 #include <linux/kernel.h>
  23 #include <linux/mm.h>
  24 #include <linux/stddef.h>
  25 #include <linux/unistd.h>
  26 #include <linux/ptrace.h>
  27 #include <linux/slab.h>
  28 #include <linux/tty.h>
  29 #include <linux/ioport.h>
  30 #include <linux/delay.h>
  31 #include <linux/console.h>
  32 #include <linux/init.h>
  33 #include <linux/bootmem.h>
  34 #include <linux/seq_file.h>
  35 #include <linux/serial.h>
  36 #include <linux/initrd.h>
  37 #include <linux/of_fdt.h>
  38 #include <linux/of.h>
  39 #include <linux/memblock.h>
  40 #include <linux/device.h>
  41 #include <linux/of_platform.h>
  42
  43 #include <asm/segment.h>
  44 #include <asm/pgtable.h>
  45 #include <asm/types.h>
  46 #include <asm/setup.h>
  47 #include <asm/io.h>
  48 #include <asm/cpuinfo.h>
  49 #include <asm/delay.h>
  50
  51 #include "vmlinux.h"
  52
  53 char __initdata cmd_line[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
  54
  55 static unsigned long __init setup_memory(void)
  56 {
  57         unsigned long bootmap_size;
  58         unsigned long ram_start_pfn;
  59         unsigned long free_ram_start_pfn;
  60         unsigned long ram_end_pfn;
  61         phys_addr_t memory_start, memory_end;
  62         struct memblock_region *region;
  63
  64         memory_end = memory_start = 0;
  65
  66         /* Find main memory where is the kernel */
  67         for_each_memblock(memory, region) {
  68                 memory_start = region->base;
  69                 memory_end = region->base + region->size;
  70                 printk(KERN_INFO "%s: Memory: 0x%x-0x%x\n", __func__,
  71                        memory_start, memory_end);
  72         }
  73
  74         if (!memory_end) {
  75                 panic("No memory!");
  76         }
  77
  78         ram_start_pfn = PFN_UP(memory_start);
  79         /* free_ram_start_pfn is first page after kernel */
  80         free_ram_start_pfn = PFN_UP(__pa(&_end));
  81         ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
  82
  83         max_pfn = ram_end_pfn;
  84
  85         /*
  86          * initialize the boot-time allocator (with low memory only).
  87          *
  88          * This makes the memory from the end of the kernel to the end of
  89          * RAM usable.
  90          * init_bootmem sets the global values min_low_pfn, max_low_pfn.
  91          */
  92         bootmap_size = init_bootmem(free_ram_start_pfn,
  93                                     ram_end_pfn - ram_start_pfn);
  94         free_bootmem(PFN_PHYS(free_ram_start_pfn),
  95                      (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
  96         reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
  97                         BOOTMEM_DEFAULT);
  98
  99         for_each_memblock(reserved, region) {
 100                 printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
 101                        (u32) region->base, (u32) region->size);
 102                 reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
 103         }
 104
 105         return ram_end_pfn;
 106 }
 107
 108 struct cpuinfo cpuinfo;
 109
 110 static void print_cpuinfo(void)
 111 {
 112         unsigned long upr = mfspr(SPR_UPR);
 113         unsigned long vr = mfspr(SPR_VR);
 114         unsigned int version;
 115         unsigned int revision;
 116
 117         version = (vr & SPR_VR_VER) >> 24;
 118         revision = (vr & SPR_VR_REV);
 119
 120         printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
 121                version, revision, cpuinfo.clock_frequency / 1000000);
 122
 123         if (!(upr & SPR_UPR_UP)) {
 124                 printk(KERN_INFO
 125                        "-- no UPR register... unable to detect configuration\n");
 126                 return;
 127         }
 128
 129         if (upr & SPR_UPR_DCP)
 130                 printk(KERN_INFO
 131                        "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
 132                        cpuinfo.dcache_size, cpuinfo.dcache_block_size, 1);
 133         else
 134                 printk(KERN_INFO "-- dcache disabled\n");
 135         if (upr & SPR_UPR_ICP)
 136                 printk(KERN_INFO
 137                        "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
 138                        cpuinfo.icache_size, cpuinfo.icache_block_size, 1);
 139         else
 140                 printk(KERN_INFO "-- icache disabled\n");
 141
 142         if (upr & SPR_UPR_DMP)
 143                 printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
 144                        1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
 145                        1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
 146         if (upr & SPR_UPR_IMP)
 147                 printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
 148                        1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
 149                        1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
 150
 151         printk(KERN_INFO "-- additional features:\n");
 152         if (upr & SPR_UPR_DUP)
 153                 printk(KERN_INFO "-- debug unit\n");
 154         if (upr & SPR_UPR_PCUP)
 155                 printk(KERN_INFO "-- performance counters\n");
 156         if (upr & SPR_UPR_PMP)
 157                 printk(KERN_INFO "-- power management\n");
 158         if (upr & SPR_UPR_PICP)
 159                 printk(KERN_INFO "-- PIC\n");
 160         if (upr & SPR_UPR_TTP)
 161                 printk(KERN_INFO "-- timer\n");
 162         if (upr & SPR_UPR_CUP)
 163                 printk(KERN_INFO "-- custom unit(s)\n");
 164 }
 165
 166 void __init setup_cpuinfo(void)
 167 {
 168         struct device_node *cpu;
 169         unsigned long iccfgr, dccfgr;
 170         unsigned long cache_set_size, cache_ways;
 171
 172         cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
 173         if (!cpu)
 174                 panic("No compatible CPU found in device tree...\n");
 175
 176         iccfgr = mfspr(SPR_ICCFGR);
 177         cache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
 178         cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
 179         cpuinfo.icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
 180         cpuinfo.icache_size =
 181             cache_set_size * cache_ways * cpuinfo.icache_block_size;
 182
 183         dccfgr = mfspr(SPR_DCCFGR);
 184         cache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
 185         cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
 186         cpuinfo.dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
 187         cpuinfo.dcache_size =
 188             cache_set_size * cache_ways * cpuinfo.dcache_block_size;
 189
 190         if (of_property_read_u32(cpu, "clock-frequency",
 191                                  &cpuinfo.clock_frequency)) {
 192                 printk(KERN_WARNING
 193                        "Device tree missing CPU 'clock-frequency' parameter."
 194                        "Assuming frequency 25MHZ"
 195                        "This is probably not what you want.");
 196         }
 197
 198         of_node_put(cpu);
 199
 200         print_cpuinfo();
 201 }
 202
 203 /**
 204  * or32_early_setup
 205  *
 206  * Handles the pointer to the device tree that this kernel is to use
 207  * for establishing the available platform devices.
 208  *
 209  * Falls back on built-in device tree in case null pointer is passed.
 210  */
 211
 212 void __init or32_early_setup(unsigned int fdt)
 213 {
 214         if (fdt) {
 215                 early_init_devtree((void*) fdt);
 216                 printk(KERN_INFO "FDT at 0x%08x\n", fdt);
 217         } else {
 218                 early_init_devtree(__dtb_start);
 219                 printk(KERN_INFO "Compiled-in FDT at %p\n", __dtb_start);
 220         }
 221 }
 222
 223 static int __init openrisc_device_probe(void)
 224 {
 225         of_platform_populate(NULL, NULL, NULL, NULL);
 226
 227         return 0;
 228 }
 229
 230 device_initcall(openrisc_device_probe);
 231
 232 static inline unsigned long extract_value_bits(unsigned long reg,
 233                                                short bit_nr, short width)
 234 {
 235         return (reg >> bit_nr) & (0 << width);
 236 }
 237
 238 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
 239 {
 240         while (!(mask & 0x1)) {
 241                 reg = reg >> 1;
 242                 mask = mask >> 1;
 243         }
 244         return mask & reg;
 245 }
 246
 247 void __init detect_unit_config(unsigned long upr, unsigned long mask,
 248                                char *text, void (*func) (void))
 249 {
 250         if (text != NULL)
 251                 printk("%s", text);
 252
 253         if (upr & mask) {
 254                 if (func != NULL)
 255                         func();
 256                 else
 257                         printk("present\n");
 258         } else
 259                 printk("not present\n");
 260 }
 261
 262 /*
 263  * calibrate_delay
 264  *
 265  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
 266  * from the clock frequency passed in via the device tree
 267  *
 268  */
 269
 270 void calibrate_delay(void)
 271 {
 272         const int *val;
 273         struct device_node *cpu = NULL;
 274         cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
 275         val = of_get_property(cpu, "clock-frequency", NULL);
 276         if (!val)
 277                 panic("no cpu 'clock-frequency' parameter in device tree");
 278         loops_per_jiffy = *val / HZ;
 279         pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
 280                 loops_per_jiffy / (500000 / HZ),
 281                 (loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
 282 }
 283
 284 void __init setup_arch(char **cmdline_p)
 285 {
 286         unsigned long max_low_pfn;
 287
 288         unflatten_device_tree();
 289
 290         setup_cpuinfo();
 291
 292         /* process 1's initial memory region is the kernel code/data */
 293         init_mm.start_code = (unsigned long)&_stext;
 294         init_mm.end_code = (unsigned long)&_etext;
 295         init_mm.end_data = (unsigned long)&_edata;
 296         init_mm.brk = (unsigned long)&_end;
 297
 298 #ifdef CONFIG_BLK_DEV_INITRD
 299         initrd_start = (unsigned long)&__initrd_start;
 300         initrd_end = (unsigned long)&__initrd_end;
 301         if (initrd_start == initrd_end) {
 302                 initrd_start = 0;
 303                 initrd_end = 0;
 304         }
 305         initrd_below_start_ok = 1;
 306 #endif
 307
 308         /* setup bootmem allocator */
 309         max_low_pfn = setup_memory();
 310
 311         /* paging_init() sets up the MMU and marks all pages as reserved */
 312         paging_init();
 313
 314 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
 315         if (!conswitchp)
 316                 conswitchp = &dummy_con;
 317 #endif
 318
 319         *cmdline_p = cmd_line;
 320
 321         printk(KERN_INFO "OpenRISC Linux -- http://openrisc.net\n");
 322 }
 323
 324 static int show_cpuinfo(struct seq_file *m, void *v)
 325 {
 326         unsigned long vr;
 327         int version, revision;
 328
 329         vr = mfspr(SPR_VR);
 330         version = (vr & SPR_VR_VER) >> 24;
 331         revision = vr & SPR_VR_REV;
 332
 333         return seq_printf(m,
 334                           "cpu\t\t: OpenRISC-%x\n"
 335                           "revision\t: %d\n"
 336                           "frequency\t: %ld\n"
 337                           "dcache size\t: %d bytes\n"
 338                           "dcache block size\t: %d bytes\n"
 339                           "icache size\t: %d bytes\n"
 340                           "icache block size\t: %d bytes\n"
 341                           "immu\t\t: %d entries, %lu ways\n"
 342                           "dmmu\t\t: %d entries, %lu ways\n"
 343                           "bogomips\t: %lu.%02lu\n",
 344                           version,
 345                           revision,
 346                           loops_per_jiffy * HZ,
 347                           cpuinfo.dcache_size,
 348                           cpuinfo.dcache_block_size,
 349                           cpuinfo.icache_size,
 350                           cpuinfo.icache_block_size,
 351                           1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
 352                           1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW),
 353                           1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
 354                           1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW),
 355                           (loops_per_jiffy * HZ) / 500000,
 356                           ((loops_per_jiffy * HZ) / 5000) % 100);
 357 }
 358
 359 static void *c_start(struct seq_file *m, loff_t * pos)
 360 {
 361         /* We only have one CPU... */
 362         return *pos < 1 ? (void *)1 : NULL;
 363 }
 364
 365 static void *c_next(struct seq_file *m, void *v, loff_t * pos)
 366 {
 367         ++*pos;
 368         return NULL;
 369 }
 370
 371 static void c_stop(struct seq_file *m, void *v)
 372 {
 373 }
 374
 375 const struct seq_operations cpuinfo_op = {
 376         .start = c_start,
 377         .next = c_next,
 378         .stop = c_stop,
 379         .show = show_cpuinfo,
 380 };