xref: /openbmc/linux/arch/arm/mach-omap1/ocpi.c (revision 95e9fd10)
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);
113