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#include <linux/soc/ti/omap1-io.h>
24
25#include "hardware.h"
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(v: val, OCPI_PROT);
58
59 val = omap_readl(OCPI_SEC);
60 val &= ~0xff;
61 omap_writel(v: 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, id: "l3_ocpi_ck");
73 if (IS_ERR(ptr: ocpi_ck))
74 return PTR_ERR(ptr: ocpi_ck);
75
76 clk_prepare_enable(clk: 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_unprepare(clk: ocpi_ck);
91 clk_put(clk: 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

source code of linux/arch/arm/mach-omap1/ocpi.c