LXR linux/arch/arm/mach-omap1/ocpi.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * linux/arch/arm/plat-omap/ocpi.c
   4 *
   5 * Minimal OCP bus support for omap16xx
   6 *
   7 * Copyright (C) 2003 - 2005 Nokia Corporation
   8 * Copyright (C) 2012 Texas Instruments, Inc.
   9 * Written by Tony Lindgren <tony@atomide.com>
  10 *
  11 * Modified for clock framework by Paul Mundt <paul.mundt@nokia.com>.
  12 */
  13
  14#include <linux/module.h>
  15#include <linux/types.h>
  16#include <linux/errno.h>
  17#include <linux/kernel.h>
  18#include <linux/init.h>
  19#include <linux/spinlock.h>
  20#include <linux/err.h>
  21#include <linux/clk.h>
  22#include <linux/io.h>
  23
  24#include <mach/hardware.h>
  25
  26#include "common.h"
  27
  28#define OCPI_BASE               0xfffec320
  29#define OCPI_FAULT              (OCPI_BASE + 0x00)
  30#define OCPI_CMD_FAULT          (OCPI_BASE + 0x04)
  31#define OCPI_SINT0              (OCPI_BASE + 0x08)
  32#define OCPI_TABORT             (OCPI_BASE + 0x0c)
  33#define OCPI_SINT1              (OCPI_BASE + 0x10)
  34#define OCPI_PROT               (OCPI_BASE + 0x14)
  35#define OCPI_SEC                (OCPI_BASE + 0x18)
  36
  37/* USB OHCI OCPI access error registers */
  38#define HOSTUEADDR      0xfffba0e0
  39#define HOSTUESTATUS    0xfffba0e4
  40
  41static struct clk *ocpi_ck;
  42
  43/*
  44 * Enables device access to OMAP buses via the OCPI bridge
  45 */
  46int ocpi_enable(void)
  47{
  48        unsigned int val;
  49
  50        if (!cpu_is_omap16xx())
  51                return -ENODEV;
  52
  53        /* Enable access for OHCI in OCPI */
  54        val = omap_readl(OCPI_PROT);
  55        val &= ~0xff;
  56        /* val &= (1 << 0);      Allow access only to EMIFS */
  57        omap_writel(val, OCPI_PROT);
  58
  59        val = omap_readl(OCPI_SEC);
  60        val &= ~0xff;
  61        omap_writel(val, OCPI_SEC);
  62
  63        return 0;
  64}
  65EXPORT_SYMBOL(ocpi_enable);
  66
  67static int __init omap_ocpi_init(void)
  68{
  69        if (!cpu_is_omap16xx())
  70                return -ENODEV;
  71
  72        ocpi_ck = clk_get(NULL, "l3_ocpi_ck");
  73        if (IS_ERR(ocpi_ck))
  74                return PTR_ERR(ocpi_ck);
  75
  76        clk_enable(ocpi_ck);
  77        ocpi_enable();
  78        pr_info("OMAP OCPI interconnect driver loaded\n");
  79
  80        return 0;
  81}
  82
  83static void __exit omap_ocpi_exit(void)
  84{
  85        /* REVISIT: Disable OCPI */
  86
  87        if (!cpu_is_omap16xx())
  88                return;
  89
  90        clk_disable(ocpi_ck);
  91        clk_put(ocpi_ck);
  92}
  93
  94MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
  95MODULE_DESCRIPTION("OMAP OCPI bus controller module");
  96MODULE_LICENSE("GPL");
  97module_init(omap_ocpi_init);
  98module_exit(omap_ocpi_exit);
  99