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/config.h>
  27 #include <linux/module.h>
  28 #include <linux/types.h>
  29 #include <linux/errno.h>
  30 #include <linux/kernel.h>
  31 #include <linux/init.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/err.h>
  34
  35 #include <asm/io.h>
  36 #include <asm/hardware/clock.h>
  37 #include <asm/hardware.h>
  38
  39 #define OCPI_BASE               0xfffec320
  40 #define OCPI_FAULT              (OCPI_BASE + 0x00)
  41 #define OCPI_CMD_FAULT          (OCPI_BASE + 0x04)
  42 #define OCPI_SINT0              (OCPI_BASE + 0x08)
  43 #define OCPI_TABORT             (OCPI_BASE + 0x0c)
  44 #define OCPI_SINT1              (OCPI_BASE + 0x10)
  45 #define OCPI_PROT               (OCPI_BASE + 0x14)
  46 #define OCPI_SEC                (OCPI_BASE + 0x18)
  47
  48 /* USB OHCI OCPI access error registers */
  49 #define HOSTUEADDR      0xfffba0e0
  50 #define HOSTUESTATUS    0xfffba0e4
  51
  52 static struct clk *ocpi_ck;
  53
  54 /*
  55  * Enables device access to OMAP buses via the OCPI bridge
  56  * FIXME: Add locking
  57  */
  58 int ocpi_enable(void)
  59 {
  60         unsigned int val;
  61
  62         if (!cpu_is_omap16xx())
  63                 return -ENODEV;
  64
  65         /* Make sure there's clock for OCPI */
  66         clk_enable(ocpi_ck);
  67
  68         /* Enable access for OHCI in OCPI */
  69         val = omap_readl(OCPI_PROT);
  70         val &= ~0xff;
  71         //val &= (1 << 0);      /* Allow access only to EMIFS */
  72         omap_writel(val, OCPI_PROT);
  73
  74         val = omap_readl(OCPI_SEC);
  75         val &= ~0xff;
  76         omap_writel(val, OCPI_SEC);
  77
  78         return 0;
  79 }
  80 EXPORT_SYMBOL(ocpi_enable);
  81
  82 static int __init omap_ocpi_init(void)
  83 {
  84         if (!cpu_is_omap16xx())
  85                 return -ENODEV;
  86
  87         ocpi_ck = clk_get(NULL, "l3_ocpi_ck");
  88         if (IS_ERR(ocpi_ck))
  89                 return PTR_ERR(ocpi_ck);
  90
  91         clk_use(ocpi_ck);
  92         ocpi_enable();
  93         printk("OMAP OCPI interconnect driver loaded\n");
  94
  95         return 0;
  96 }
  97
  98 static void __exit omap_ocpi_exit(void)
  99 {
 100         /* REVISIT: Disable OCPI */
 101
 102         if (!cpu_is_omap16xx())
 103                 return;
 104
 105         clk_unuse(ocpi_ck);
 106         clk_put(ocpi_ck);
 107 }
 108
 109 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
 110 MODULE_DESCRIPTION("OMAP OCPI bus controller module");
 111 MODULE_LICENSE("GPL");
 112 module_init(omap_ocpi_init);
 113 module_exit(omap_ocpi_exit);