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 };
  46
  47 static inline void *to_ram_addr(void *addr)
  48 {
  49         u32 base;
  50
  51         base = KSEG0ADDR(RALINK_SOC_SDRAM_BASE);
  52         if (((u32) addr > base) &&
  53             ((u32) addr < (base + RALINK_SOC_MEM_SIZE_MAX)))
  54                 return addr;
  55
  56         base = KSEG1ADDR(RALINK_SOC_SDRAM_BASE);
  57         if (((u32) addr > base) &&
  58             ((u32) addr < (base + RALINK_SOC_MEM_SIZE_MAX)))
  59                 return addr;
  60
  61         /* some U-Boot variants uses physical addresses */
  62         base = RALINK_SOC_SDRAM_BASE;
  63         if (((u32) addr > base) &&
  64             ((u32) addr < (base + RALINK_SOC_MEM_SIZE_MAX)))
  65                 return (void *)KSEG0ADDR(addr);
  66
  67         return NULL;
  68 }
  69
  70 static __init char *ramips_prom_getargv(const char *name)
  71 {
  72         int len = strlen(name);
  73         int i;
  74
  75         if (!ramips_prom_argv) {
  76                 printk(KERN_DEBUG "argv=%p is invalid, skipping\n",
  77                        ramips_prom_argv);
  78                 return NULL;
  79         }
  80
  81         for (i = 0; i < ramips_prom_argc; i++) {
  82                 char *argv = to_ram_addr(ramips_prom_argv[i]);
  83
  84                 if (!argv) {
  85                         printk(KERN_DEBUG
  86                                "argv[%d]=%p is invalid, skipping\n",
  87                                i, ramips_prom_argv[i]);
  88                         continue;
  89                 }
  90
  91                 printk(KERN_DEBUG "argv[%d]: %s\n", i, argv);
  92                 if (strncmp(name, argv, len) == 0 && (argv)[len] == '=')
  93                         return argv + len + 1;
  94         }
  95
  96         return NULL;
  97 }
  98
  99 static __init char *ramips_prom_getenv(const char *envname)
 100 {
 101 #define PROM_MAX_ENVS   256
 102         int len = strlen(envname);
 103         char **env;
 104         int i;
 105
 106         env = ramips_prom_envp;
 107         if (!env) {
 108                 printk(KERN_DEBUG "envp=%p is not in RAM, skipping\n",
 109                        ramips_prom_envp);
 110                 return NULL;
 111         }
 112
 113         for (i = 0; i < PROM_MAX_ENVS; i++) {
 114                 char *p = to_ram_addr(env[i]);
 115
 116                 if (!p)
 117                         break;
 118
 119                 printk(KERN_DEBUG "env[%d]: %s\n", i, p);
 120                 if (strncmp(envname, p, len) == 0 && p[len] == '=')
 121                         return p + len + 1;
 122         }
 123
 124         return NULL;
 125 #undef PROM_MAX_ENVS
 126 }
 127
 128 static __init void find_board_byname(char *name)
 129 {
 130         int i;
 131
 132         for (i = 0; i < ARRAY_SIZE(boards); i++)
 133                 if (strcmp(name, boards[i].name) == 0) {
 134                         ramips_mach = boards[i].mach_type;
 135                         break;
 136                 }
 137 }
 138
 139 void __init prom_init(void)
 140 {
 141         char *p;
 142
 143         printk(KERN_DEBUG
 144                "prom: fw_arg0=%08x, fw_arg1=%08x, fw_arg2=%08x, fw_arg3=%08x\n",
 145                (unsigned int)fw_arg0, (unsigned int)fw_arg1,
 146                (unsigned int)fw_arg2, (unsigned int)fw_arg3);
 147
 148         ramips_prom_argc = fw_arg0;
 149         ramips_prom_argv = to_ram_addr((void *)fw_arg1);
 150         ramips_prom_envp = to_ram_addr((void *)fw_arg2);
 151
 152         p = ramips_prom_getargv("board");
 153         if (!p)
 154                 p = ramips_prom_getenv("board");
 155         if (p)
 156                 find_board_byname(p);
 157 }
 158
 159 void __init prom_free_prom_memory(void)
 160 {
 161         /* We do not have to prom memory to free */
 162 }