arch/arm/plat-omap/ocpi.c

   1 /*
   2  * linux/arch/arm/plat-omap/ocpi.c
   3  *
   4  * Minimal OCP bus support for omap16xx
   5  *
   6  * Copyright (C) 2003 - 2005 Nokia Corporation
   7  * Written by Tony Lindgren <tony@atomide.com>
   8  *
   9  * Modified for clock framework by Paul Mundt <paul.mundt@nokia.com>.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/types.h>
  28 #include <linux/errno.h>
  29 #include <linux/kernel.h>
  30 #include <linux/init.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/err.h>
  33 #include <linux/clk.h>
  34
  35 #include <asm/io.h>
  36 #include <mach/hardware.h>
  37
  38 #define OCPI_BASE               0xfffec320
  39 #define OCPI_FAULT              (OCPI_BASE + 0x00)
  40 #define OCPI_CMD_FAULT          (OCPI_BASE + 0x04)
  41 #define OCPI_SINT0              (OCPI_BASE + 0x08)
  42 #define OCPI_TABORT             (OCPI_BASE + 0x0c)
  43 #define OCPI_SINT1              (OCPI_BASE + 0x10)
  44 #define OCPI_PROT               (OCPI_BASE + 0x14)
  45 #define OCPI_SEC                (OCPI_BASE + 0x18)
  46
  47 /* USB OHCI OCPI access error registers */
  48 #define HOSTUEADDR      0xfffba0e0
  49 #define HOSTUESTATUS    0xfffba0e4
  50
  51 static struct clk *ocpi_ck;
  52
  53 /*
  54  * Enables device access to OMAP buses via the OCPI bridge
  55  * FIXME: Add locking
  56  */
  57 int ocpi_enable(void)
  58 {
  59         unsigned int val;
  60
  61         if (!cpu_is_omap16xx())
  62                 return -ENODEV;
  63
  64         /* Enable access for OHCI in OCPI */
  65         val = omap_readl(OCPI_PROT);
  66         val &= ~0xff;
  67         //val &= (1 << 0);      /* Allow access only to EMIFS */
  68         omap_writel(val, OCPI_PROT);
  69
  70         val = omap_readl(OCPI_SEC);
  71         val &= ~0xff;
  72         omap_writel(val, OCPI_SEC);
  73
  74         return 0;
  75 }
  76 EXPORT_SYMBOL(ocpi_enable);
  77
  78 static int __init omap_ocpi_init(void)
  79 {
  80         if (!cpu_is_omap16xx())
  81                 return -ENODEV;
  82
  83         ocpi_ck = clk_get(NULL, "l3_ocpi_ck");
  84         if (IS_ERR(ocpi_ck))
  85                 return PTR_ERR(ocpi_ck);
  86
  87         clk_enable(ocpi_ck);
  88         ocpi_enable();
  89         printk("OMAP OCPI interconnect driver loaded\n");
  90
  91         return 0;
  92 }
  93
  94 static void __exit omap_ocpi_exit(void)
  95 {
  96         /* REVISIT: Disable OCPI */
  97
  98         if (!cpu_is_omap16xx())
  99                 return;
 100
 101         clk_disable(ocpi_ck);
 102         clk_put(ocpi_ck);
 103 }
 104
 105 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
 106 MODULE_DESCRIPTION("OMAP OCPI bus controller module");
 107 MODULE_LICENSE("GPL");
 108 module_init(omap_ocpi_init);
 109 module_exit(omap_ocpi_exit);