target/linux/adm5120-2.6/files/arch/mips/adm5120/prom.c

   1 /*****************************************************************************
   2  * Carsten Langgaard, carstenl@mips.com
   3  * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
   4  * Copyright (C) 2003 ADMtek Incorporated.
   5  *      daniell@admtek.com.tw
   6  *
   7  *  This program is free software; you can distribute it and/or modify it
   8  *  under the terms of the GNU General Public License (Version 2) as
   9  *  published by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope it will be useful, but WITHOUT
  12  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  *  for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License along
  17  *  with this program; if not, write to the Free Software Foundation, Inc.,
  18  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  19  *
  20  *****************************************************************************/
  21
  22 #include <linux/init.h>
  23 #include <linux/autoconf.h>
  24 #include <linux/kernel.h>
  25 #include <linux/string.h>
  26 #include <linux/mm.h>
  27 #include <linux/bootmem.h>
  28
  29 #include <asm/bootinfo.h>
  30 #include <asm/addrspace.h>
  31
  32 /* boot loaders specific definitions */
  33 #define CFE_EPTSEAL 0x43464531
  34 #define CFE 1
  35 #define MYLOADER 2
  36 #define UNKNOWN 0
  37
  38 void setup_prom_printf(int);
  39 void prom_printf(char *, ...);
  40 void prom_meminit(void);
  41
  42 /* we assume we don't know the boot loader by default */
  43 int boot_loader_type = UNKNOWN;
  44
  45 #define ADM5120_ENVC           1
  46
  47 char *adm5120_envp[2*ADM5120_ENVC] = {"memsize","0x001000000"};
  48
  49 #define READCSR(r)      *(volatile unsigned long *)(0xB2600000+(r))
  50 #define WRITECSR(r,v)   *(volatile unsigned long *)(0xB2600000+(r)) = v
  51
  52 #define UART_DR_REG         0x00
  53 #define UART_FR_REG         0x18
  54 #define UART_TX_FIFO_FULL   0x20
  55
  56 int putPromChar(char c)
  57 {
  58         WRITECSR(UART_DR_REG, c);
  59         while ( (READCSR(UART_FR_REG) & UART_TX_FIFO_FULL) );
  60         return 0;
  61 }
  62
  63 /*
  64  * Ugly prom_printf used for debugging
  65  */
  66
  67 void prom_printf(char *fmt, ...)
  68 {
  69         va_list args;
  70         int l;
  71         char *p, *buf_end;
  72         char buf[1024];
  73
  74         va_start(args, fmt);
  75         l = vsprintf(buf, fmt, args); /* hopefully i < sizeof(buf) */
  76         va_end(args);
  77
  78         buf_end = buf + l;
  79
  80         for (p = buf; p < buf_end; p++) {
  81                 /* Crude cr/nl handling is better than none */
  82                 if (*p == '\n')
  83                         putPromChar('\r');
  84                 putPromChar(*p);
  85         }
  86 }
  87
  88 char *prom_getenv(char *envname)
  89 {
  90         int i, index=0;
  91
  92         i = strlen(envname);
  93
  94         printk(KERN_INFO "GETENV: envname is %s\n", envname);
  95
  96         while(index < (2*ADM5120_ENVC)) {
  97                 if(strncmp(envname, adm5120_envp[index], i) == 0) {
  98                         printk(KERN_INFO "GETENV: returning %s\n", adm5120_envp[index+1]);
  99                         return(adm5120_envp[index+1]);
 100                 }
 101                 index += 2;
 102         }
 103
 104         printk(KERN_INFO "GETENV: not found.\n");
 105         return(NULL);
 106 }
 107
 108 /*
 109  * initialize the prom module.
 110  */
 111 void __init prom_init(void)
 112 {
 113         /* you should these macros defined in include/asm/bootinfo.h */
 114         mips_machgroup = MACH_GROUP_ADM_GW;
 115         mips_machtype = MACH_ADM_GW_5120;
 116
 117         /* init command line, register a default kernel command line */
 118         strcpy(&(arcs_cmdline[0]), "console=ttyS0,115200 rootfstype=squashfs,jffs2 init=/etc/preinit");
 119
 120         /* check for CFE by finding the CFE magic number */
 121         int *prom_vec = (int *) fw_arg3;
 122         int argc = fw_arg0;
 123         unsigned int cfe_eptseal;
 124
 125         if (argc < 0)
 126                 cfe_eptseal = (uint32_t)(unsigned long)prom_vec;
 127         else {
 128                 if ((int32_t)(long)prom_vec < 0)
 129                          /*
 130                           * Old loaders all it gives us is the handle,
 131                           * so assume the seal.
 132                           */
 133                         cfe_eptseal = CFE_EPTSEAL;
 134                 else
 135                         /*
 136                          * Newer loaders bundle the handle/ept/eptseal
 137                          */
 138                         cfe_eptseal = (unsigned int)((uint32_t *)prom_vec)[3];
 139         }
 140         if (cfe_eptseal == CFE_EPTSEAL) {
 141                 boot_loader_type = CFE;
 142                 printk("adm5120 : CFE boot loader\n");
 143         }
 144
 145         /* init memory map */
 146         prom_meminit();
 147 }