arch/arm/mach-omap1/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  * Copyright (C) 2012 Texas Instruments, Inc.
   8  * Written by Tony Lindgren <tony@atomide.com>
   9  *
  10  * Modified for clock framework by Paul Mundt <paul.mundt@nokia.com>.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  */
  26
  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 #include <linux/clk.h>
  35 #include <linux/io.h>
  36
  37 #include <mach/hardware.h>
  38
  39 #include "common.h"
  40
  41 #define OCPI_BASE               0xfffec320
  42 #define OCPI_FAULT              (OCPI_BASE + 0x00)
  43 #define OCPI_CMD_FAULT          (OCPI_BASE + 0x04)
  44 #define OCPI_SINT0              (OCPI_BASE + 0x08)
  45 #define OCPI_TABORT             (OCPI_BASE + 0x0c)
  46 #define OCPI_SINT1              (OCPI_BASE + 0x10)
  47 #define OCPI_PROT               (OCPI_BASE + 0x14)
  48 #define OCPI_SEC                (OCPI_BASE + 0x18)
  49
  50 /* USB OHCI OCPI access error registers */
  51 #define HOSTUEADDR      0xfffba0e0
  52 #define HOSTUESTATUS    0xfffba0e4
  53
  54 static struct clk *ocpi_ck;
  55
  56 /*
  57  * Enables device access to OMAP buses via the OCPI bridge
  58  * FIXME: Add locking
  59  */
  60 int ocpi_enable(void)
  61 {
  62         unsigned int val;
  63
  64         if (!cpu_is_omap16xx())
  65                 return -ENODEV;
  66
  67         /* Enable access for OHCI in OCPI */
  68         val = omap_readl(OCPI_PROT);
  69         val &= ~0xff;
  70         /* val &= (1 << 0);      Allow access only to EMIFS */
  71         omap_writel(val, OCPI_PROT);
  72
  73         val = omap_readl(OCPI_SEC);
  74         val &= ~0xff;
  75         omap_writel(val, OCPI_SEC);
  76
  77         return 0;
  78 }
  79 EXPORT_SYMBOL(ocpi_enable);
  80
  81 static int __init omap_ocpi_init(void)
  82 {
  83         if (!cpu_is_omap16xx())
  84                 return -ENODEV;
  85
  86         ocpi_ck = clk_get(NULL, "l3_ocpi_ck");
  87         if (IS_ERR(ocpi_ck))
  88                 return PTR_ERR(ocpi_ck);
  89
  90         clk_enable(ocpi_ck);
  91         ocpi_enable();
  92         pr_info("OMAP OCPI interconnect driver loaded\n");
  93
  94         return 0;
  95 }
  96
  97 static void __exit omap_ocpi_exit(void)
  98 {
  99         /* REVISIT: Disable OCPI */
 100
 101         if (!cpu_is_omap16xx())
 102                 return;
 103
 104         clk_disable(ocpi_ck);
 105         clk_put(ocpi_ck);
 106 }
 107
 108 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
 109 MODULE_DESCRIPTION("OMAP OCPI bus controller module");
 110 MODULE_LICENSE("GPL");
 111 module_init(omap_ocpi_init);
 112 module_exit(omap_ocpi_exit);