xref: /netbsd-src/sys/arch/arm/broadcom/bcm53xx_mdio.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*-
2  * Copyright (c) 2012 The NetBSD Foundation, Inc.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to The NetBSD Foundation
6  * by Matt Thomas of 3am Software Foundry.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #define MII_PRIVATE
31 
32 #include "locators.h"
33 
34 #include <sys/cdefs.h>
35 
36 __KERNEL_RCSID(1, "$NetBSD: bcm53xx_mdio.c,v 1.1 2012/09/01 00:04:44 matt Exp $");
37 
38 #include <sys/bus.h>
39 #include <sys/device.h>
40 #include <sys/intr.h>
41 #include <sys/systm.h>
42 
43 #include <arm/broadcom/bcm53xx_reg.h>
44 #include <arm/broadcom/bcm53xx_var.h>
45 
46 static int bcmmdio_ccb_match(device_t, cfdata_t, void *);
47 static void bcmmdio_ccb_attach(device_t, device_t, void *);
48 
49 CFATTACH_DECL_NEW(bcmmdio_ccb, sizeof(struct bcmmdio_softc),
50 	bcmmdio_ccb_match, bcmmdio_ccb_attach, NULL, NULL);
51 
52 static inline uint32_t
53 bcmmdio_read_4(struct bcmmdio_softc *sc, bus_size_t o)
54 {
55 	return bus_space_read_4(sc->sc_bst, sc->sc_bsh, o);
56 }
57 
58 static inline void
59 bcmmdio_write_4(struct bcmmdio_softc *sc, bus_size_t o, uint32_t v)
60 {
61 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, o, v);
62 }
63 
64 static int
65 bcmmdio_ccb_match(device_t parent, cfdata_t cf, void *aux)
66 {
67 	struct bcmccb_attach_args * const ccbaa = aux;
68 	const struct bcm_locators * const loc = &ccbaa->ccbaa_loc;
69 
70 	if (strcmp(cf->cf_name, loc->loc_name))
71 		return 0;
72 
73 	KASSERT(cf->cf_loc[BCMCCBCF_PORT] == BCMCCBCF_PORT_DEFAULT);
74 
75 	return 1;
76 }
77 
78 static void
79 bcmmdio_ccb_attach(device_t parent, device_t self, void *aux)
80 {
81 	struct bcmmdio_softc * const sc = device_private(self);
82 	struct bcmccb_attach_args * const ccbaa = aux;
83 	const struct bcm_locators * const loc = &ccbaa->ccbaa_loc;
84 
85 	sc->sc_dev = self;
86 
87 	sc->sc_bst = ccbaa->ccbaa_ccb_bst;
88 	sc->sc_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_VM);
89 
90 	bus_space_subregion(sc->sc_bst, ccbaa->ccbaa_ccb_bsh,
91 	    loc->loc_offset, loc->loc_size, &sc->sc_bsh);
92 
93 	uint32_t miimgt = bcmmdio_read_4(sc, MIIMGT);
94 	uint32_t div = __SHIFTOUT(miimgt, MIIMGT_MDCDIV);
95 	if (div == 0) {
96 		div = 33;			// divisor to get 2MHz
97 		miimgt &= ~MIIMGT_MDCDIV;
98 		miimgt |= __SHIFTIN(div, MIIMGT_MDCDIV);
99 		bcmmdio_write_4(sc, MIIMGT, miimgt);
100 	}
101 	uint32_t freq = 66000000 / div;
102 
103 	aprint_naive("\n");
104 	aprint_normal(": MDIO bus @ %u MHz\n", freq / 1000000);
105 }
106 
107 static void
108 bcmmdio_select_bus(struct bcmmdio_softc *sc, int phy)
109 {
110 	uint32_t mgt = bcmmdio_read_4(sc, MIIMGT);
111 	uint32_t new_mgt = mgt;
112 
113 	KASSERT((mgt & MIIMGT_BSY) == 0);
114 	if (__BIT(phy) & MII_INTERNAL) {
115 		new_mgt &= ~MIIMGT_EXT;
116 	} else {
117 		new_mgt |= MIIMGT_EXT;
118 	}
119 
120 	if (mgt != new_mgt)
121 		bcmmdio_write_4(sc, MIIMGT, new_mgt);
122 }
123 
124 static void
125 bcmmdio_busywait(struct bcmmdio_softc *sc)
126 {
127 	while (bcmmdio_read_4(sc, MIIMGT) & MIIMGT_BSY) {
128 		delay(1);
129 	}
130 }
131 
132 int
133 bcmmdio_mii_readreg(device_t self, int phy, int reg)
134 {
135 	struct bcmmdio_softc * const sc = device_private(self);
136 
137 	mutex_enter(sc->sc_lock);
138 
139 	bcmmdio_select_bus(sc, phy);
140 
141 	bcmmdio_write_4(sc, MIICMD, MIICMD_RD(phy, reg));
142 
143 	bcmmdio_busywait(sc);
144 
145 	int val = __SHIFTOUT(bcmmdio_read_4(sc, MIICMD), MIICMD_DATA);
146 	mutex_exit(sc->sc_lock);
147 	return val;
148 }
149 
150 void
151 bcmmdio_mii_writereg(device_t self, int phy, int reg, int val)
152 {
153 	struct bcmmdio_softc * const sc = device_private(self);
154 
155 	KASSERT((val & 0xffff) == val);
156 
157 	mutex_enter(sc->sc_lock);
158 
159 	bcmmdio_select_bus(sc, phy);
160 
161 	bcmmdio_write_4(sc, MIICMD, MIICMD_WR(phy, reg, val));
162 
163 	bcmmdio_busywait(sc);
164 
165 	mutex_exit(sc->sc_lock);
166 }
167