xref: /netbsd-src/sys/dev/pci/amdpm.c (revision 9c1da17e908379b8a470f1117a6395bd6a0ca559)
1 /*	$NetBSD: amdpm.c,v 1.8 2005/06/28 00:28:41 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Enami Tsugutomo.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: amdpm.c,v 1.8 2005/06/28 00:28:41 thorpej Exp $");
41 
42 #include "opt_amdpm.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/device.h>
48 #include <sys/callout.h>
49 #include <sys/rnd.h>
50 
51 #include <dev/pci/pcivar.h>
52 #include <dev/pci/pcireg.h>
53 #include <dev/pci/pcidevs.h>
54 
55 #include <dev/pci/amdpmreg.h>
56 
57 struct amdpm_softc {
58 	struct device sc_dev;
59 
60 	pci_chipset_tag_t sc_pc;
61 	pcitag_t sc_tag;
62 
63 	bus_space_tag_t sc_iot;
64 	bus_space_handle_t sc_ioh;		/* PMxx space */
65 
66 	struct callout sc_rnd_ch;
67 	rndsource_element_t sc_rnd_source;
68 #ifdef AMDPM_RND_COUNTERS
69 	struct evcnt sc_rnd_hits;
70 	struct evcnt sc_rnd_miss;
71 	struct evcnt sc_rnd_data[256];
72 #endif
73 };
74 
75 static void	amdpm_rnd_callout(void *);
76 
77 #ifdef AMDPM_RND_COUNTERS
78 #define	AMDPM_RNDCNT_INCR(ev)	(ev)->ev_count++
79 #else
80 #define	AMDPM_RNDCNT_INCR(ev)	/* nothing */
81 #endif
82 
83 static int
84 amdpm_match(struct device *parent, struct cfdata *match, void *aux)
85 {
86 	struct pci_attach_args *pa = aux;
87 
88 	if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_AMD &&
89 	    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_AMD_PBC768_PMC)
90 		return (1);
91 	return (0);
92 }
93 
94 static void
95 amdpm_attach(struct device *parent, struct device *self, void *aux)
96 {
97 	struct amdpm_softc *sc = (struct amdpm_softc *) self;
98 	struct pci_attach_args *pa = aux;
99 	pcireg_t reg;
100 	u_int32_t pmreg;
101 	int i;
102 
103 	aprint_naive("\n");
104 	aprint_normal("\n");
105 
106 	sc->sc_pc = pa->pa_pc;
107 	sc->sc_tag = pa->pa_tag;
108 	sc->sc_iot = pa->pa_iot;
109 
110 #if 0
111 	aprint_normal("%s: ", sc->sc_dev.dv_xname);
112 	pci_conf_print(pa->pa_pc, pa->pa_tag, NULL);
113 #endif
114 
115 	reg = pci_conf_read(pa->pa_pc, pa->pa_tag, AMDPM_CONFREG);
116 	if ((reg & AMDPM_PMIOEN) == 0) {
117 		aprint_error("%s: PMxx space isn't enabled\n",
118 		    sc->sc_dev.dv_xname);
119 		return;
120 	}
121 	reg = pci_conf_read(pa->pa_pc, pa->pa_tag, AMDPM_PMPTR);
122 	if (bus_space_map(sc->sc_iot, AMDPM_PMBASE(reg), AMDPM_PMSIZE,
123 	    0, &sc->sc_ioh)) {
124 		aprint_error("%s: failed to map PMxx space\n",
125 		    sc->sc_dev.dv_xname);
126 		return;
127 	}
128 
129 	reg = pci_conf_read(pa->pa_pc, pa->pa_tag, AMDPM_CONFREG);
130 	if (reg & AMDPM_RNGEN) {
131 		/* Check to see if we can read data from the RNG. */
132 		(void) bus_space_read_4(sc->sc_iot, sc->sc_ioh,
133 		    AMDPM_RNGDATA);
134 		for (i = 0; i < 1000; i++) {
135 			pmreg = bus_space_read_4(sc->sc_iot,
136 			    sc->sc_ioh, AMDPM_RNGSTAT);
137 			if (pmreg & AMDPM_RNGDONE)
138 				break;
139 			delay(1);
140 		}
141 		if ((pmreg & AMDPM_RNGDONE) != 0) {
142 			aprint_normal("%s: "
143 			    "random number generator enabled (apprx. %dms)\n",
144 			    sc->sc_dev.dv_xname, i);
145 			callout_init(&sc->sc_rnd_ch);
146 			rnd_attach_source(&sc->sc_rnd_source,
147 			    sc->sc_dev.dv_xname, RND_TYPE_RNG,
148 			    /*
149 			     * XXX Careful!  The use of RND_FLAG_NO_ESTIMATE
150 			     * XXX here is unobvious: we later feed raw bits
151 			     * XXX into the "entropy pool" with rnd_add_data,
152 			     * XXX explicitly supplying an entropy estimate.
153 			     * XXX In this context, NO_ESTIMATE serves only
154 			     * XXX to prevent rnd_add_data from trying to
155 			     * XXX use the *time at which we added the data*
156 			     * XXX as entropy, which is not a good idea since
157 			     * XXX we add data periodically from a callout.
158 			     */
159 			    RND_FLAG_NO_ESTIMATE);
160 #ifdef AMDPM_RND_COUNTERS
161 			evcnt_attach_dynamic(&sc->sc_rnd_hits, EVCNT_TYPE_MISC,
162 			    NULL, sc->sc_dev.dv_xname, "rnd hits");
163 			evcnt_attach_dynamic(&sc->sc_rnd_miss, EVCNT_TYPE_MISC,
164 			    NULL, sc->sc_dev.dv_xname, "rnd miss");
165 			for (i = 0; i < 256; i++) {
166 				evcnt_attach_dynamic(&sc->sc_rnd_data[i],
167 				    EVCNT_TYPE_MISC, NULL, sc->sc_dev.dv_xname,
168 				    "rnd data");
169 			}
170 #endif
171 			amdpm_rnd_callout(sc);
172 		}
173 	}
174 }
175 
176 CFATTACH_DECL(amdpm, sizeof(struct amdpm_softc),
177     amdpm_match, amdpm_attach, NULL, NULL);
178 
179 static void
180 amdpm_rnd_callout(void *v)
181 {
182 	struct amdpm_softc *sc = v;
183 	u_int32_t reg;
184 #ifdef AMDPM_RND_COUNTERS
185 	int i;
186 #endif
187 
188 	if ((bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_RNGSTAT) &
189 	    AMDPM_RNGDONE) != 0) {
190 		reg = bus_space_read_4(sc->sc_iot, sc->sc_ioh, AMDPM_RNGDATA);
191 		rnd_add_data(&sc->sc_rnd_source, &reg,
192 		    sizeof(reg), sizeof(reg) * NBBY);
193 #ifdef AMDPM_RND_COUNTERS
194 		AMDPM_RNDCNT_INCR(&sc->sc_rnd_hits);
195 		for (i = 0; i < sizeof(reg); i++, reg >>= NBBY)
196 			AMDPM_RNDCNT_INCR(&sc->sc_rnd_data[reg & 0xff]);
197 #endif
198 	} else
199 		AMDPM_RNDCNT_INCR(&sc->sc_rnd_miss);
200 	callout_reset(&sc->sc_rnd_ch, 1, amdpm_rnd_callout, sc);
201 }
202