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/system.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 char __initdata cmd_line[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
  55
  56 static unsigned long __init setup_memory(void)
  57 {
  58         unsigned long bootmap_size;
  59         unsigned long ram_start_pfn;
  60         unsigned long free_ram_start_pfn;
  61         unsigned long ram_end_pfn;
  62         phys_addr_t memory_start, memory_end;
  63         struct memblock_region *region;
  64
  65         memory_end = memory_start = 0;
  66
  67         /* Find main memory where is the kernel */
  68         for_each_memblock(memory, region) {
  69                 memory_start = region->base;
  70                 memory_end = region->base + region->size;
  71                 printk(KERN_INFO "%s: Memory: 0x%x-0x%x\n", __func__,
  72                        memory_start, memory_end);
  73         }
  74
  75         if (!memory_end) {
  76                 panic("No memory!");
  77         }
  78
  79         ram_start_pfn = PFN_UP(memory_start);
  80         /* free_ram_start_pfn is first page after kernel */
  81         free_ram_start_pfn = PFN_UP(__pa(&_end));
  82         ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
  83
  84         max_pfn = ram_end_pfn;
  85
  86         /*
  87          * initialize the boot-time allocator (with low memory only).
  88          *
  89          * This makes the memory from the end of the kernel to the end of
  90          * RAM usable.
  91          * init_bootmem sets the global values min_low_pfn, max_low_pfn.
  92          */
  93         bootmap_size = init_bootmem(free_ram_start_pfn,
  94                                     ram_end_pfn - ram_start_pfn);
  95         free_bootmem(PFN_PHYS(free_ram_start_pfn),
  96                      (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
  97         reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
  98                         BOOTMEM_DEFAULT);
  99
 100         for_each_memblock(reserved, region) {
 101                 printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
 102                        (u32) region->base, (u32) region->size);
 103                 reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
 104         }
 105
 106         return ram_end_pfn;
 107 }
 108
 109 struct cpuinfo cpuinfo;
 110
 111 static void print_cpuinfo(void)
 112 {
 113         unsigned long upr = mfspr(SPR_UPR);
 114         unsigned long vr = mfspr(SPR_VR);
 115         unsigned int version;
 116         unsigned int revision;
 117
 118         version = (vr & SPR_VR_VER) >> 24;
 119         revision = (vr & SPR_VR_REV);
 120
 121         printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
 122                version, revision, cpuinfo.clock_frequency / 1000000);
 123
 124         if (!(upr & SPR_UPR_UP)) {
 125                 printk(KERN_INFO
 126                        "-- no UPR register... unable to detect configuration\n");
 127                 return;
 128         }
 129
 130         if (upr & SPR_UPR_DCP)
 131                 printk(KERN_INFO
 132                        "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
 133                        cpuinfo.dcache_size, cpuinfo.dcache_block_size, 1);
 134         else
 135                 printk(KERN_INFO "-- dcache disabled\n");
 136         if (upr & SPR_UPR_ICP)
 137                 printk(KERN_INFO
 138                        "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
 139                        cpuinfo.icache_size, cpuinfo.icache_block_size, 1);
 140         else
 141                 printk(KERN_INFO "-- icache disabled\n");
 142
 143         if (upr & SPR_UPR_DMP)
 144                 printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
 145                        1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
 146                        1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
 147         if (upr & SPR_UPR_IMP)
 148                 printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
 149                        1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
 150                        1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
 151
 152         printk(KERN_INFO "-- additional features:\n");
 153         if (upr & SPR_UPR_DUP)
 154                 printk(KERN_INFO "-- debug unit\n");
 155         if (upr & SPR_UPR_PCUP)
 156                 printk(KERN_INFO "-- performance counters\n");
 157         if (upr & SPR_UPR_PMP)
 158                 printk(KERN_INFO "-- power management\n");
 159         if (upr & SPR_UPR_PICP)
 160                 printk(KERN_INFO "-- PIC\n");
 161         if (upr & SPR_UPR_TTP)
 162                 printk(KERN_INFO "-- timer\n");
 163         if (upr & SPR_UPR_CUP)
 164                 printk(KERN_INFO "-- custom unit(s)\n");
 165 }
 166
 167 void __init setup_cpuinfo(void)
 168 {
 169         struct device_node *cpu;
 170         unsigned long iccfgr, dccfgr;
 171         unsigned long cache_set_size, cache_ways;
 172
 173         cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
 174         if (!cpu)
 175                 panic("No compatible CPU found in device tree...\n");
 176
 177         iccfgr = mfspr(SPR_ICCFGR);
 178         cache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
 179         cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
 180         cpuinfo.icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
 181         cpuinfo.icache_size =
 182             cache_set_size * cache_ways * cpuinfo.icache_block_size;
 183
 184         dccfgr = mfspr(SPR_DCCFGR);
 185         cache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
 186         cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
 187         cpuinfo.dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
 188         cpuinfo.dcache_size =
 189             cache_set_size * cache_ways * cpuinfo.dcache_block_size;
 190
 191         if (of_property_read_u32(cpu, "clock-frequency",
 192                                  &cpuinfo.clock_frequency)) {
 193                 printk(KERN_WARNING
 194                        "Device tree missing CPU 'clock-frequency' parameter."
 195                        "Assuming frequency 25MHZ"
 196                        "This is probably not what you want.");
 197         }
 198
 199         of_node_put(cpu);
 200
 201         print_cpuinfo();
 202 }
 203
 204 /**
 205  * or32_early_setup
 206  *
 207  * Handles the pointer to the device tree that this kernel is to use
 208  * for establishing the available platform devices.
 209  *
 210  * For now, this is limited to using the built-in device tree.  In the future,
 211  * it is intended that this function will take a pointer to the device tree
 212  * that is potentially built-in, but potentially also passed in by the
 213  * bootloader, or discovered by some equally clever means...
 214  */
 215
 216 void __init or32_early_setup(void)
 217 {
 218
 219         early_init_devtree(__dtb_start);
 220
 221         printk(KERN_INFO "Compiled-in FDT at 0x%p\n", __dtb_start);
 222 }
 223
 224 static int __init openrisc_device_probe(void)
 225 {
 226         of_platform_populate(NULL, NULL, NULL, NULL);
 227
 228         return 0;
 229 }
 230
 231 device_initcall(openrisc_device_probe);
 232
 233 static inline unsigned long extract_value_bits(unsigned long reg,
 234                                                short bit_nr, short width)
 235 {
 236         return (reg >> bit_nr) & (0 << width);
 237 }
 238
 239 static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
 240 {
 241         while (!(mask & 0x1)) {
 242                 reg = reg >> 1;
 243                 mask = mask >> 1;
 244         }
 245         return mask & reg;
 246 }
 247
 248 void __init detect_unit_config(unsigned long upr, unsigned long mask,
 249                                char *text, void (*func) (void))
 250 {
 251         if (text != NULL)
 252                 printk("%s", text);
 253
 254         if (upr & mask) {
 255                 if (func != NULL)
 256                         func();
 257                 else
 258                         printk("present\n");
 259         } else
 260                 printk("not present\n");
 261 }
 262
 263 /*
 264  * calibrate_delay
 265  *
 266  * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
 267  * from the clock frequency passed in via the device tree
 268  *
 269  */
 270
 271 void __cpuinit calibrate_delay(void)
 272 {
 273         const int *val;
 274         struct device_node *cpu = NULL;
 275         cpu = of_find_compatible_node(NULL, NULL, "opencores,or1200-rtlsvn481");
 276         val = of_get_property(cpu, "clock-frequency", NULL);
 277         if (!val)
 278                 panic("no cpu 'clock-frequency' parameter in device tree");
 279         loops_per_jiffy = *val / HZ;
 280         pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
 281                 loops_per_jiffy / (500000 / HZ),
 282                 (loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
 283 }
 284
 285 void __init setup_arch(char **cmdline_p)
 286 {
 287         unsigned long max_low_pfn;
 288
 289         unflatten_device_tree();
 290
 291         setup_cpuinfo();
 292
 293         /* process 1's initial memory region is the kernel code/data */
 294         init_mm.start_code = (unsigned long)&_stext;
 295         init_mm.end_code = (unsigned long)&_etext;
 296         init_mm.end_data = (unsigned long)&_edata;
 297         init_mm.brk = (unsigned long)&_end;
 298
 299 #ifdef CONFIG_BLK_DEV_INITRD
 300         initrd_start = (unsigned long)&__initrd_start;
 301         initrd_end = (unsigned long)&__initrd_end;
 302         if (initrd_start == initrd_end) {
 303                 initrd_start = 0;
 304                 initrd_end = 0;
 305         }
 306         initrd_below_start_ok = 1;
 307 #endif
 308
 309         /* setup bootmem allocator */
 310         max_low_pfn = setup_memory();
 311
 312         /* paging_init() sets up the MMU and marks all pages as reserved */
 313         paging_init();
 314
 315 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
 316         if (!conswitchp)
 317                 conswitchp = &dummy_con;
 318 #endif
 319
 320         *cmdline_p = cmd_line;
 321
 322         printk(KERN_INFO "OpenRISC Linux -- http://openrisc.net\n");
 323 }
 324
 325 static int show_cpuinfo(struct seq_file *m, void *v)
 326 {
 327         unsigned long vr;
 328         int version, revision;
 329
 330         vr = mfspr(SPR_VR);
 331         version = (vr & SPR_VR_VER) >> 24;
 332         revision = vr & SPR_VR_REV;
 333
 334         return seq_printf(m,
 335                           "cpu\t\t: OpenRISC-%x\n"
 336                           "revision\t: %d\n"
 337                           "frequency\t: %ld\n"
 338                           "dcache size\t: %d bytes\n"
 339                           "dcache block size\t: %d bytes\n"
 340                           "icache size\t: %d bytes\n"
 341                           "icache block size\t: %d bytes\n"
 342                           "immu\t\t: %d entries, %lu ways\n"
 343                           "dmmu\t\t: %d entries, %lu ways\n"
 344                           "bogomips\t: %lu.%02lu\n",
 345                           version,
 346                           revision,
 347                           loops_per_jiffy * HZ,
 348                           cpuinfo.dcache_size,
 349                           cpuinfo.dcache_block_size,
 350                           cpuinfo.icache_size,
 351                           cpuinfo.icache_block_size,
 352                           1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
 353                           1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW),
 354                           1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
 355                           1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW),
 356                           (loops_per_jiffy * HZ) / 500000,
 357                           ((loops_per_jiffy * HZ) / 5000) % 100);
 358 }
 359
 360 static void *c_start(struct seq_file *m, loff_t * pos)
 361 {
 362         /* We only have one CPU... */
 363         return *pos < 1 ? (void *)1 : NULL;
 364 }
 365
 366 static void *c_next(struct seq_file *m, void *v, loff_t * pos)
 367 {
 368         ++*pos;
 369         return NULL;
 370 }
 371
 372 static void c_stop(struct seq_file *m, void *v)
 373 {
 374 }
 375
 376 const struct seq_operations cpuinfo_op = {
 377         .start = c_start,
 378         .next = c_next,
 379         .stop = c_stop,
 380         .show = show_cpuinfo,
 381 };