arch/mips/rb532/prom.c

   1 /*
   2  *  RouterBoard 500 specific prom routines
   3  *
   4  *  Copyright (C) 2003, Peter Sadik <peter.sadik@idt.com>
   5  *  Copyright (C) 2005-2006, P.Christeas <p_christ@hol.gr>
   6  *  Copyright (C) 2007, Gabor Juhos <juhosg@openwrt.org>
   7  *                      Felix Fietkau <nbd@openwrt.org>
   8  *                      Florian Fainelli <florian@openwrt.org>
   9  *
  10  *  This program is free software; you can redistribute it and/or
  11  *  modify it under the terms of the GNU General Public License
  12  *  as published by the Free Software Foundation; either version 2
  13  *  of the License, or (at your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *  GNU General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License
  21  *  along with this program; if not, write to the
  22  *  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23  *  Boston, MA  02110-1301, USA.
  24  *
  25  */
  26
  27 #include <linux/init.h>
  28 #include <linux/mm.h>
  29 #include <linux/module.h>
  30 #include <linux/string.h>
  31 #include <linux/console.h>
  32 #include <linux/bootmem.h>
  33 #include <linux/ioport.h>
  34 #include <linux/blkdev.h>
  35
  36 #include <asm/bootinfo.h>
  37 #include <asm/mach-rc32434/ddr.h>
  38 #include <asm/mach-rc32434/prom.h>
  39
  40 unsigned int idt_cpu_freq = 132000000;
  41 EXPORT_SYMBOL(idt_cpu_freq);
  42
  43 static struct resource ddr_reg[] = {
  44         {
  45                 .name = "ddr-reg",
  46                 .start = DDR0_PHYS_ADDR,
  47                 .end = DDR0_PHYS_ADDR + sizeof(struct ddr_ram),
  48                 .flags = IORESOURCE_MEM,
  49         }
  50 };
  51
  52 void __init prom_free_prom_memory(void)
  53 {
  54         /* No prom memory to free */
  55 }
  56
  57 static inline int match_tag(char *arg, const char *tag)
  58 {
  59         return strncmp(arg, tag, strlen(tag)) == 0;
  60 }
  61
  62 static inline unsigned long tag2ul(char *arg, const char *tag)
  63 {
  64         char *num;
  65
  66         num = arg + strlen(tag);
  67         return simple_strtoul(num, 0, 10);
  68 }
  69
  70 void __init prom_setup_cmdline(void)
  71 {
  72         static char cmd_line[COMMAND_LINE_SIZE] __initdata;
  73         char *cp, *board;
  74         int prom_argc;
  75         char **prom_argv;
  76         int i;
  77
  78         prom_argc = fw_arg0;
  79         prom_argv = (char **) fw_arg1;
  80
  81         cp = cmd_line;
  82                 /* Note: it is common that parameters start
  83                  * at argv[1] and not argv[0],
  84                  * however, our elf loader starts at [0] */
  85         for (i = 0; i < prom_argc; i++) {
  86                 if (match_tag(prom_argv[i], FREQ_TAG)) {
  87                         idt_cpu_freq = tag2ul(prom_argv[i], FREQ_TAG);
  88                         continue;
  89                 }
  90 #ifdef IGNORE_CMDLINE_MEM
  91                 /* parses out the "mem=xx" arg */
  92                 if (match_tag(prom_argv[i], MEM_TAG))
  93                         continue;
  94 #endif
  95                 if (i > 0)
  96                         *(cp++) = ' ';
  97                 if (match_tag(prom_argv[i], BOARD_TAG)) {
  98                         board = prom_argv[i] + strlen(BOARD_TAG);
  99
 100                         if (match_tag(board, BOARD_RB532A))
 101                                 mips_machtype = MACH_MIKROTIK_RB532A;
 102                         else
 103                                 mips_machtype = MACH_MIKROTIK_RB532;
 104                 }
 105
 106                 strcpy(cp, prom_argv[i]);
 107                 cp += strlen(prom_argv[i]);
 108         }
 109         *(cp++) = ' ';
 110
 111         i = strlen(arcs_cmdline);
 112         if (i > 0) {
 113                 *(cp++) = ' ';
 114                 strcpy(cp, arcs_cmdline);
 115                 cp += strlen(arcs_cmdline);
 116         }
 117         cmd_line[COMMAND_LINE_SIZE - 1] = '\0';
 118
 119         strcpy(arcs_cmdline, cmd_line);
 120 }
 121
 122 void __init prom_init(void)
 123 {
 124         struct ddr_ram __iomem *ddr;
 125         phys_addr_t memsize;
 126         phys_addr_t ddrbase;
 127
 128         ddr = ioremap_nocache(ddr_reg[0].start,
 129                         ddr_reg[0].end - ddr_reg[0].start);
 130
 131         if (!ddr) {
 132                 printk(KERN_ERR "Unable to remap DDR register\n");
 133                 return;
 134         }
 135
 136         ddrbase = (phys_addr_t)&ddr->ddrbase;
 137         memsize = (phys_addr_t)&ddr->ddrmask;
 138         memsize = 0 - memsize;
 139
 140         prom_setup_cmdline();
 141
 142         /* give all RAM to boot allocator,
 143          * except for the first 0x400 and the last 0x200 bytes */
 144         add_memory_region(ddrbase + 0x400, memsize - 0x600, BOOT_MEM_RAM);
 145 }