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 /* CFE1 is the magic number to recognize CFE from other bootloaders */
  34 #define CFE 1
  35 #define UBOOT 2
  36 #define MYLOADER 3
  37 #define UNKNOWN 0
  38
  39 void setup_prom_printf(int);
  40 void prom_printf(char *, ...);
  41 void prom_meminit(void);
  42
  43 /* we assume we don't know the boot loader by default */
  44 int boot_loader_type = UNKNOWN;
  45
  46 #define ADM5120_ENVC           1
  47
  48 char *adm5120_envp[2*ADM5120_ENVC] = {"memsize","0x001000000"};
  49
  50 #define READCSR(r)      *(volatile unsigned long *)(0xB2600000+(r))
  51 #define WRITECSR(r,v)   *(volatile unsigned long *)(0xB2600000+(r)) = v
  52
  53 #define UART_DR_REG         0x00
  54 #define UART_FR_REG         0x18
  55 #define UART_TX_FIFO_FULL   0x20
  56
  57 int putPromChar(char c)
  58 {
  59         WRITECSR(UART_DR_REG, c);
  60         while ( (READCSR(UART_FR_REG) & UART_TX_FIFO_FULL) );
  61         return 0;
  62 }
  63
  64 /*
  65  * Ugly prom_printf used for debugging
  66  */
  67
  68 void prom_printf(char *fmt, ...)
  69 {
  70         va_list args;
  71         int l;
  72         char *p, *buf_end;
  73         char buf[1024];
  74
  75         va_start(args, fmt);
  76         l = vsprintf(buf, fmt, args); /* hopefully i < sizeof(buf) */
  77         va_end(args);
  78
  79         buf_end = buf + l;
  80
  81         for (p = buf; p < buf_end; p++) {
  82                 /* Crude cr/nl handling is better than none */
  83                 if (*p == '\n')
  84                         putPromChar('\r');
  85                 putPromChar(*p);
  86         }
  87 }
  88
  89 char *prom_getenv(char *envname)
  90 {
  91         int i, index=0;
  92
  93         i = strlen(envname);
  94
  95         printk(KERN_INFO "GETENV: envname is %s\n", envname);
  96
  97         while(index < (2*ADM5120_ENVC)) {
  98                 if(strncmp(envname, adm5120_envp[index], i) == 0) {
  99                         printk(KERN_INFO "GETENV: returning %s\n", adm5120_envp[index+1]);
 100                         return(adm5120_envp[index+1]);
 101                 }
 102                 index += 2;
 103         }
 104
 105         printk(KERN_INFO "GETENV: not found.\n");
 106         return(NULL);
 107 }
 108
 109 /*
 110  * initialize the prom module.
 111  */
 112 void __init prom_init(void)
 113 {
 114         /* you should these macros defined in include/asm/bootinfo.h */
 115         mips_machgroup = MACH_GROUP_ADM_GW;
 116         mips_machtype = MACH_ADM_GW_5120;
 117
 118         /* init command line, register a default kernel command line */
 119         strcpy(&(arcs_cmdline[0]), "console=ttyS0,115200 rootfstype=squashfs,jffs2 init=/etc/preinit");
 120
 121         /* check for CFE by finding the CFE magic number */
 122         int *prom_vec = (int *) fw_arg3;
 123         int argc = fw_arg0;
 124         unsigned int cfe_eptseal;
 125
 126         if (argc < 0)
 127                 cfe_eptseal = (uint32_t)(unsigned long)prom_vec;
 128         else {
 129                 if ((int32_t)(long)prom_vec < 0)
 130                          /*
 131                           * Old loaders all it gives us is the handle,
 132                           * so assume the seal.
 133                           */
 134                         cfe_eptseal = CFE_EPTSEAL;
 135                 else
 136                         /*
 137                          * Newer loaders bundle the handle/ept/eptseal
 138                          */
 139                         cfe_eptseal = (unsigned int)((uint32_t *)prom_vec)[3];
 140         }
 141         if (cfe_eptseal == CFE_EPTSEAL) {
 142                 boot_loader_type = CFE;
 143                 printk("adm5120 : CFE boot loader\n");
 144         }
 145
 146         /* init memory map */
 147         prom_meminit();
 148 }