cpu/ixp/cpu.c

   1 /*
   2  * (C) Copyright 2002
   3  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   4  * Marius Groeger <mgroeger@sysgo.de>
   5  *
   6  * (C) Copyright 2002
   7  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   8  * Alex Zuepke <azu@sysgo.de>
   9  *
  10  * See file CREDITS for list of people who contributed to this
  11  * project.
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License as
  15  * published by the Free Software Foundation; either version 2 of
  16  * the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  26  * MA 02111-1307 USA
  27  */
  28
  29 /*
  30  * CPU specific code
  31  */
  32
  33 #include <common.h>
  34 #include <command.h>
  35 #include <asm/arch/ixp425.h>
  36
  37 int cpu_init (void)
  38 {
  39         /*
  40          * setup up stacks if necessary
  41          */
  42 #ifdef CONFIG_USE_IRQ
  43         DECLARE_GLOBAL_DATA_PTR;
  44
  45         IRQ_STACK_START = _armboot_start - CFG_MALLOC_LEN - CFG_GBL_DATA_SIZE - 4;
  46         FIQ_STACK_START = IRQ_STACK_START - CONFIG_STACKSIZE_IRQ;
  47 #endif
  48
  49         pci_init();
  50         return 0;
  51 }
  52
  53 int cleanup_before_linux (void)
  54 {
  55         /*
  56          * this function is called just before we call linux
  57          * it prepares the processor for linux
  58          *
  59          * just disable everything that can disturb booting linux
  60          */
  61
  62         unsigned long i;
  63
  64         disable_interrupts ();
  65
  66         /* turn off I-cache */
  67         asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
  68         i &= ~0x1000;
  69         asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
  70
  71         /* flush I-cache */
  72         asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
  73
  74         return (0);
  75 }
  76
  77 int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
  78 {
  79         printf ("resetting ...\n");
  80
  81         udelay (50000);                         /* wait 50 ms */
  82         disable_interrupts ();
  83         reset_cpu (0);
  84
  85         /*NOTREACHED*/
  86         return (0);
  87 }
  88
  89 /* taken from blob */
  90 void icache_enable (void)
  91 {
  92         register u32 i;
  93
  94         /* read control register */
  95         asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
  96
  97         /* set i-cache */
  98         i |= 0x1000;
  99
 100         /* write back to control register */
 101         asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
 102 }
 103
 104 void icache_disable (void)
 105 {
 106         register u32 i;
 107
 108         /* read control register */
 109         asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
 110
 111         /* clear i-cache */
 112         i &= ~0x1000;
 113
 114         /* write back to control register */
 115         asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
 116
 117         /* flush i-cache */
 118         asm ("mcr p15, 0, %0, c7, c5, 0": :"r" (i));
 119 }
 120
 121 int icache_status (void)
 122 {
 123         register u32 i;
 124
 125         /* read control register */
 126         asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
 127
 128         /* return bit */
 129         return (i & 0x1000);
 130 }
 131
 132 /* we will never enable dcache, because we have to setup MMU first */
 133 void dcache_enable (void)
 134 {
 135         return;
 136 }
 137
 138 void dcache_disable (void)
 139 {
 140         return;
 141 }
 142
 143 int dcache_status (void)
 144 {
 145         return 0;                                       /* always off */
 146 }
 147
 148 /* FIXME */
 149 /*
 150 void pci_init(void)
 151 {
 152         return;
 153 }
 154 */