xref: /netbsd-src/sys/arch/arm/broadcom/bcm53xx_mdio.c (revision 02bbc407aa67a8c12508cf69e1303e4177d37814)
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 1.2 2014/02/19 22:21:16 matt Exp $");
37 
38 #include <sys/param.h>
39 #include <sys/bus.h>
40 #include <sys/device.h>
41 #include <sys/intr.h>
42 #include <sys/systm.h>
43 
44 #include <arm/broadcom/bcm53xx_reg.h>
45 #include <arm/broadcom/bcm53xx_var.h>
46 
47 static int bcmmdio_ccb_match(device_t, cfdata_t, void *);
48 static void bcmmdio_ccb_attach(device_t, device_t, void *);
49 
50 CFATTACH_DECL_NEW(bcmmdio_ccb, sizeof(struct bcmmdio_softc),
51 	bcmmdio_ccb_match, bcmmdio_ccb_attach, NULL, NULL);
52 
53 static inline uint32_t
bcmmdio_read_4(struct bcmmdio_softc * sc,bus_size_t o)54 bcmmdio_read_4(struct bcmmdio_softc *sc, bus_size_t o)
55 {
56 	return bus_space_read_4(sc->sc_bst, sc->sc_bsh, o);
57 }
58 
59 static inline void
bcmmdio_write_4(struct bcmmdio_softc * sc,bus_size_t o,uint32_t v)60 bcmmdio_write_4(struct bcmmdio_softc *sc, bus_size_t o, uint32_t v)
61 {
62 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, o, v);
63 }
64 
65 static int
bcmmdio_ccb_match(device_t parent,cfdata_t cf,void * aux)66 bcmmdio_ccb_match(device_t parent, cfdata_t cf, void *aux)
67 {
68 	struct bcmccb_attach_args * const ccbaa = aux;
69 	const struct bcm_locators * const loc = &ccbaa->ccbaa_loc;
70 
71 	if (strcmp(cf->cf_name, loc->loc_name))
72 		return 0;
73 
74 	KASSERT(cf->cf_loc[BCMCCBCF_PORT] == BCMCCBCF_PORT_DEFAULT);
75 
76 	return 1;
77 }
78 
79 static void
bcmmdio_ccb_attach(device_t parent,device_t self,void * aux)80 bcmmdio_ccb_attach(device_t parent, device_t self, void *aux)
81 {
82 	struct bcmmdio_softc * const sc = device_private(self);
83 	struct bcmccb_attach_args * const ccbaa = aux;
84 	const struct bcm_locators * const loc = &ccbaa->ccbaa_loc;
85 
86 	sc->sc_dev = self;
87 
88 	sc->sc_bst = ccbaa->ccbaa_ccb_bst;
89 	sc->sc_lock = mutex_obj_alloc(MUTEX_DEFAULT, IPL_VM);
90 
91 	bus_space_subregion(sc->sc_bst, ccbaa->ccbaa_ccb_bsh,
92 	    loc->loc_offset, loc->loc_size, &sc->sc_bsh);
93 
94 	uint32_t miimgt = bcmmdio_read_4(sc, MIIMGT);
95 	uint32_t div = __SHIFTOUT(miimgt, MIIMGT_MDCDIV);
96 	if (div == 0) {
97 		div = 33;			// divisor to get 2MHz
98 		miimgt &= ~MIIMGT_MDCDIV;
99 		miimgt |= __SHIFTIN(div, MIIMGT_MDCDIV);
100 		bcmmdio_write_4(sc, MIIMGT, miimgt);
101 	}
102 	uint32_t freq = 66000000 / div;
103 
104 	aprint_naive("\n");
105 	aprint_normal(": MDIO bus @ %u MHz\n", freq / 1000000);
106 }
107 
108 static void
bcmmdio_select_bus(struct bcmmdio_softc * sc,int phy)109 bcmmdio_select_bus(struct bcmmdio_softc *sc, int phy)
110 {
111 	uint32_t mgt = bcmmdio_read_4(sc, MIIMGT);
112 	uint32_t new_mgt = mgt;
113 
114 	KASSERT((mgt & MIIMGT_BSY) == 0);
115 	if (__BIT(phy) & MII_INTERNAL) {
116 		new_mgt &= ~MIIMGT_EXT;
117 	} else {
118 		new_mgt |= MIIMGT_EXT;
119 	}
120 
121 	if (mgt != new_mgt)
122 		bcmmdio_write_4(sc, MIIMGT, new_mgt);
123 }
124 
125 static void
bcmmdio_busywait(struct bcmmdio_softc * sc)126 bcmmdio_busywait(struct bcmmdio_softc *sc)
127 {
128 	while (bcmmdio_read_4(sc, MIIMGT) & MIIMGT_BSY) {
129 		delay(1);
130 	}
131 }
132 
133 int
bcmmdio_mii_readreg(device_t self,int phy,int reg)134 bcmmdio_mii_readreg(device_t self, int phy, int reg)
135 {
136 	struct bcmmdio_softc * const sc = device_private(self);
137 
138 	mutex_enter(sc->sc_lock);
139 
140 	bcmmdio_select_bus(sc, phy);
141 
142 	bcmmdio_write_4(sc, MIICMD, MIICMD_RD(phy, reg));
143 
144 	bcmmdio_busywait(sc);
145 
146 	int val = __SHIFTOUT(bcmmdio_read_4(sc, MIICMD), MIICMD_DATA);
147 	mutex_exit(sc->sc_lock);
148 	return val;
149 }
150 
151 void
bcmmdio_mii_writereg(device_t self,int phy,int reg,int val)152 bcmmdio_mii_writereg(device_t self, int phy, int reg, int val)
153 {
154 	struct bcmmdio_softc * const sc = device_private(self);
155 
156 	KASSERT((val & 0xffff) == val);
157 
158 	mutex_enter(sc->sc_lock);
159 
160 	bcmmdio_select_bus(sc, phy);
161 
162 	bcmmdio_write_4(sc, MIICMD, MIICMD_WR(phy, reg, val));
163 
164 	bcmmdio_busywait(sc);
165 
166 	mutex_exit(sc->sc_lock);
167 }
168