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
41 static struct clk *ocpi_ck;
42
43 /*
44 * Enables device access to OMAP buses via the OCPI bridge
45 */
46 int 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 }
65 EXPORT_SYMBOL(ocpi_enable);
66
67 static 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_prepare_enable(ocpi_ck);
77 ocpi_enable();
78 pr_info("OMAP OCPI interconnect driver loaded\n");
79
80 return 0;
81 }
82
83 static void __exit omap_ocpi_exit(void)
84 {
85 /* REVISIT: Disable OCPI */
86
87 if (!cpu_is_omap16xx())
88 return;
89
90 clk_disable_unprepare(ocpi_ck);
91 clk_put(ocpi_ck);
92 }
93
94 MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
95 MODULE_DESCRIPTION("OMAP OCPI bus controller module");
96 MODULE_LICENSE("GPL");
97 module_init(omap_ocpi_init);
98 module_exit(omap_ocpi_exit);
99
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