target/linux/ar71xx/files/arch/mips/ar71xx/prom.c

   1 /*
   2  *  Atheros AR71xx SoC specific prom routines
   3  *
   4  *  Copyright (C) 2008 Gabor Juhos <juhosg@openwrt.org>
   5  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify it
   8  *  under the terms of the GNU General Public License version 2 as published
   9  *  by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/io.h>
  15 #include <linux/serial_reg.h>
  16
  17 #include <asm/bootinfo.h>
  18 #include <asm/addrspace.h>
  19
  20 #include <asm/mach-ar71xx/ar71xx.h>
  21
  22 struct board_rec {
  23         char            *name;
  24         unsigned long   mach_type;
  25 };
  26
  27 static int prom_argc __initdata;
  28 static char **prom_argv __initdata;
  29 static char **prom_envp __initdata;
  30
  31 static struct board_rec boards[] __initdata = {
  32         {
  33                 .name           = "411",
  34                 .mach_type      = MACH_AR71XX_RB_411,
  35         }, {
  36                 .name           = "433",
  37                 .mach_type      = MACH_AR71XX_RB_433,
  38         }, {
  39                 .name           = "450",
  40                 .mach_type      = MACH_AR71XX_RB_450,
  41         }
  42 };
  43
  44 char *(*prom_getenv)(const char *envname) __initdata;
  45
  46 static __init char *dummy_getenv(const char *envname)
  47 {
  48         return NULL;
  49 }
  50
  51 static void __init routerboot_printargs(void)
  52 {
  53         int i;
  54
  55         for (i = 0; i < prom_argc; i++)
  56                 printk(KERN_DEBUG "prom: routerboot envp[%d]: %s\n",
  57                                 i, prom_envp[i]);
  58 }
  59
  60 static __init char *routerboot_getenv(const char *envname)
  61 {
  62         char **env;
  63         int i = strlen(envname);
  64
  65         for (env = prom_envp; *env != NULL; env++)
  66                 if (strncmp(envname, *env, i) == 0 && (*env)[i] == '=')
  67                         return *env + i + 1;
  68
  69         return NULL;
  70 }
  71
  72 static __init unsigned long find_board_byname(char *name)
  73 {
  74         int i;
  75
  76         for (i = 0; i < ARRAY_SIZE(boards); i++)
  77                 if (strcmp(name, boards[i].name) == 0)
  78                         return boards[i].mach_type;
  79
  80         return MACH_AR71XX_GENERIC;
  81 }
  82
  83 void __init prom_init(void)
  84 {
  85         char *board;
  86
  87         printk(KERN_DEBUG "prom: fw_arg0=%08x, fw_arg1=%08x, "
  88                         "fw_arg2=%08x, fw_arg3=%08x\n",
  89                         (unsigned int)fw_arg0, (unsigned int)fw_arg1,
  90                         (unsigned int)fw_arg2, (unsigned int)fw_arg3);
  91
  92         prom_getenv = dummy_getenv;
  93
  94         if ((fw_arg0 == 7) && (fw_arg2 == 0)) {
  95                 prom_argc = fw_arg0;
  96                 prom_envp = (char **)fw_arg1;
  97                 prom_getenv = routerboot_getenv;
  98                 routerboot_printargs();
  99         }
 100
 101         board = prom_getenv("board");
 102         if (board)
 103                 mips_machtype = find_board_byname(board);
 104         else
 105                 mips_machtype = MACH_AR71XX_GENERIC;
 106
 107         ar71xx_print_cmdline();
 108 }
 109
 110 void __init prom_free_prom_memory(void)
 111 {
 112         /* We do not have to prom memory to free */
 113 }
 114
 115 #define UART_READ(r) \
 116         __raw_readl((void __iomem *)(KSEG1ADDR(AR71XX_UART_BASE) + 4 * (r)))
 117
 118 #define UART_WRITE(r, v) \
 119         __raw_writel((v), (void __iomem *)(KSEG1ADDR(AR71XX_UART_BASE) + 4*(r)))
 120
 121 void prom_putchar(unsigned char ch)
 122 {
 123         while (((UART_READ(UART_LSR)) & UART_LSR_THRE) == 0);
 124         UART_WRITE(UART_TX, ch);
 125         while (((UART_READ(UART_LSR)) & UART_LSR_THRE) == 0);
 126 }