target/linux/ramips/files/arch/mips/ralink/common/prom.c

   1 /*
   2  *  Ralink SoC specific prom routines
   3  *
   4  *  Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify it
   7  *  under the terms of the GNU General Public License version 2 as published
   8  *  by the Free Software Foundation.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/string.h>
  14
  15 #include <asm/bootinfo.h>
  16 #include <asm/addrspace.h>
  17
  18 #include <asm/mach-ralink/common.h>
  19 #include <asm/mach-ralink/machine.h>
  20 #include <ralink_soc.h>
  21
  22 struct board_rec {
  23         char                    *name;
  24         enum ramips_mach_type   mach_type;
  25 };
  26
  27 static int ramips_prom_argc __initdata;
  28 static char **ramips_prom_argv __initdata;
  29 static char **ramips_prom_envp __initdata;
  30
  31 static struct board_rec boards[] __initdata = {
  32         {
  33                 .name           = "RT-N15",
  34                 .mach_type      = RAMIPS_MACH_RT_N15,
  35         }, {
  36                 .name           = "DIR-300-revB",
  37                 .mach_type      = RAMIPS_MACH_DIR_300_REVB,
  38         }, {
  39                 .name           = "V22RW-2X2",
  40                 .mach_type      = RAMIPS_MACH_V22RW_2X2,
  41         }, {
  42                 .name           = "WHR-G300N",
  43                 .mach_type      = RAMIPS_MACH_WHR_G300N,
  44         }, {
  45                 .name           = "FONERA20N",
  46                 .mach_type      = RAMIPS_MACH_FONERA20N,
  47         }
  48 };
  49
  50 static inline void *to_ram_addr(void *addr)
  51 {
  52         u32 base;
  53
  54         base = KSEG0ADDR(RALINK_SOC_SDRAM_BASE);
  55         if (((u32) addr > base) &&
  56             ((u32) addr < (base + RALINK_SOC_MEM_SIZE_MAX)))
  57                 return addr;
  58
  59         base = KSEG1ADDR(RALINK_SOC_SDRAM_BASE);
  60         if (((u32) addr > base) &&
  61             ((u32) addr < (base + RALINK_SOC_MEM_SIZE_MAX)))
  62                 return addr;
  63
  64         /* some U-Boot variants uses physical addresses */
  65         base = RALINK_SOC_SDRAM_BASE;
  66         if (((u32) addr > base) &&
  67             ((u32) addr < (base + RALINK_SOC_MEM_SIZE_MAX)))
  68                 return (void *)KSEG0ADDR(addr);
  69
  70         return NULL;
  71 }
  72
  73 static __init char *ramips_prom_getargv(const char *name)
  74 {
  75         int len = strlen(name);
  76         int i;
  77
  78         if (!ramips_prom_argv) {
  79                 printk(KERN_DEBUG "argv=%p is invalid, skipping\n",
  80                        ramips_prom_argv);
  81                 return NULL;
  82         }
  83
  84         for (i = 0; i < ramips_prom_argc; i++) {
  85                 char *argv = to_ram_addr(ramips_prom_argv[i]);
  86
  87                 if (!argv) {
  88                         printk(KERN_DEBUG
  89                                "argv[%d]=%p is invalid, skipping\n",
  90                                i, ramips_prom_argv[i]);
  91                         continue;
  92                 }
  93
  94                 printk(KERN_DEBUG "argv[%d]: %s\n", i, argv);
  95                 if (strncmp(name, argv, len) == 0 && (argv)[len] == '=')
  96                         return argv + len + 1;
  97         }
  98
  99         return NULL;
 100 }
 101
 102 static __init char *ramips_prom_getenv(const char *envname)
 103 {
 104 #define PROM_MAX_ENVS   256
 105         int len = strlen(envname);
 106         char **env;
 107         int i;
 108
 109         env = ramips_prom_envp;
 110         if (!env) {
 111                 printk(KERN_DEBUG "envp=%p is not in RAM, skipping\n",
 112                        ramips_prom_envp);
 113                 return NULL;
 114         }
 115
 116         for (i = 0; i < PROM_MAX_ENVS; i++) {
 117                 char *p = to_ram_addr(env[i]);
 118
 119                 if (!p)
 120                         break;
 121
 122                 printk(KERN_DEBUG "env[%d]: %s\n", i, p);
 123                 if (strncmp(envname, p, len) == 0 && p[len] == '=')
 124                         return p + len + 1;
 125         }
 126
 127         return NULL;
 128 #undef PROM_MAX_ENVS
 129 }
 130
 131 static __init void find_board_byname(char *name)
 132 {
 133         int i;
 134
 135         for (i = 0; i < ARRAY_SIZE(boards); i++)
 136                 if (strcmp(name, boards[i].name) == 0) {
 137                         ramips_mach = boards[i].mach_type;
 138                         break;
 139                 }
 140 }
 141
 142 void __init prom_init(void)
 143 {
 144         char *p;
 145
 146         printk(KERN_DEBUG
 147                "prom: fw_arg0=%08x, fw_arg1=%08x, fw_arg2=%08x, fw_arg3=%08x\n",
 148                (unsigned int)fw_arg0, (unsigned int)fw_arg1,
 149                (unsigned int)fw_arg2, (unsigned int)fw_arg3);
 150
 151         ramips_prom_argc = fw_arg0;
 152         ramips_prom_argv = to_ram_addr((void *)fw_arg1);
 153         ramips_prom_envp = to_ram_addr((void *)fw_arg2);
 154
 155         p = ramips_prom_getargv("board");
 156         if (!p)
 157                 p = ramips_prom_getenv("board");
 158         if (p)
 159                 find_board_byname(p);
 160 }
 161
 162 void __init prom_free_prom_memory(void)
 163 {
 164         /* We do not have to prom memory to free */
 165 }