linux/arch/openrisc/kernel/setup.c
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   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
  53char __initdata cmd_line[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
  54
  55static 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
 108struct cpuinfo cpuinfo;
 109
 110static 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
 166void __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
 212void __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
 223static int __init openrisc_device_probe(void)
 224{
 225        of_platform_populate(NULL, NULL, NULL, NULL);
 226
 227        return 0;
 228}
 229
 230device_initcall(openrisc_device_probe);
 231
 232static 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
 238static 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
 247void __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
 270void 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
 284void __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
 324static 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
 359static 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
 365static void *c_next(struct seq_file *m, void *v, loff_t * pos)
 366{
 367        ++*pos;
 368        return NULL;
 369}
 370
 371static void c_stop(struct seq_file *m, void *v)
 372{
 373}
 374
 375const struct seq_operations cpuinfo_op = {
 376        .start = c_start,
 377        .next = c_next,
 378        .stop = c_stop,
 379        .show = show_cpuinfo,
 380};
 381