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