1 /* $NetBSD: piixpcib.c,v 1.24 2019/10/18 15:00:15 hannken Exp $ */
2 
3 /*-
4  * Copyright (c) 2004, 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Minoura Makoto, Matthew R. Green, and Jared D. McNeill.
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Intel PIIX4 PCI-ISA bridge device driver with CPU frequency scaling support
34  *
35  * Based on the FreeBSD 'smist' cpufreq driver by Bruno Ducrot
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: piixpcib.c,v 1.24 2019/10/18 15:00:15 hannken Exp $");
40 
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/device.h>
45 #include <sys/sysctl.h>
46 #include <sys/bus.h>
47 
48 #include <machine/frame.h>
49 #include <machine/bioscall.h>
50 #include <machine/bootinfo.h>
51 
52 #include <dev/pci/pcivar.h>
53 #include <dev/pci/pcireg.h>
54 #include <dev/pci/pcidevs.h>
55 
56 #include <i386/pci/piixreg.h>
57 #include <x86/pci/pcibvar.h>
58 
59 #define             PIIX4_PIRQRC        0x60
60 
61 struct piixpcib_softc {
62           /* we call pcibattach() which assumes our softc starts like this: */
63 
64           struct pcib_softc sc_pcib;
65 
66           device_t  sc_dev;
67 
68           int                 sc_smi_cmd;
69           int                 sc_smi_data;
70           int                 sc_command;
71           int                 sc_flags;
72 
73           bus_space_tag_t     sc_iot;
74           bus_space_handle_t sc_ioh;
75 
76           pcireg_t  sc_pirqrc;
77           uint8_t             sc_elcr[2];
78 };
79 
80 static int piixpcibmatch(device_t, cfdata_t, void *);
81 static void piixpcibattach(device_t, device_t, void *);
82 
83 static bool piixpcib_suspend(device_t, const pmf_qual_t *);
84 static bool piixpcib_resume(device_t, const pmf_qual_t *);
85 
86 static void speedstep_configure(struct piixpcib_softc *,
87                                         const struct pci_attach_args *);
88 static int speedstep_sysctl_helper(SYSCTLFN_ARGS);
89 
90 static struct piixpcib_softc *speedstep_cookie;   /* XXX */
91 
92 CFATTACH_DECL_NEW(piixpcib, sizeof(struct piixpcib_softc),
93     piixpcibmatch, piixpcibattach, NULL, NULL);
94 
95 /*
96  * Autoconf callbacks.
97  */
98 static int
piixpcibmatch(device_t parent,cfdata_t match,void * aux)99 piixpcibmatch(device_t parent, cfdata_t match, void *aux)
100 {
101           struct pci_attach_args *pa = aux;
102 
103           /* We are ISA bridge, of course */
104           if (PCI_CLASS(pa->pa_class) != PCI_CLASS_BRIDGE ||
105               (PCI_SUBCLASS(pa->pa_class) != PCI_SUBCLASS_BRIDGE_ISA &&
106               PCI_SUBCLASS(pa->pa_class) != PCI_SUBCLASS_BRIDGE_MISC)) {
107                     return 0;
108           }
109 
110           /* Matches only Intel PIIX4 */
111           if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_INTEL) {
112                     switch (PCI_PRODUCT(pa->pa_id)) {
113                     case PCI_PRODUCT_INTEL_82371AB_ISA:     /* PIIX4 */
114                     case PCI_PRODUCT_INTEL_82440MX_PMC:     /* PIIX4 in MX440 */
115                               return 10;
116                     }
117           }
118 
119           return 0;
120 }
121 
122 static void
piixpcibattach(device_t parent,device_t self,void * aux)123 piixpcibattach(device_t parent, device_t self, void *aux)
124 {
125           struct pci_attach_args *pa = aux;
126           struct piixpcib_softc *sc = device_private(self);
127 
128           sc->sc_dev = self;
129           sc->sc_iot = pa->pa_iot;
130 
131           pcibattach(parent, self, aux);
132 
133           /* Set up SpeedStep. */
134           speedstep_configure(sc, pa);
135 
136           /* Map edge/level control registers */
137           if (bus_space_map(sc->sc_iot, PIIX_REG_ELCR, PIIX_REG_ELCR_SIZE, 0,
138               &sc->sc_ioh)) {
139                     aprint_error_dev(self,
140                         "can't map edge/level control registers\n");
141                     return;
142           }
143 
144           if (!pmf_device_register(self, piixpcib_suspend, piixpcib_resume))
145                     aprint_error_dev(self, "couldn't establish power handler\n");
146 }
147 
148 static bool
piixpcib_suspend(device_t dv,const pmf_qual_t * qual)149 piixpcib_suspend(device_t dv, const pmf_qual_t *qual)
150 {
151           struct piixpcib_softc *sc = device_private(dv);
152 
153           /* capture PIRQX route control registers */
154           sc->sc_pirqrc = pci_conf_read(sc->sc_pcib.sc_pc, sc->sc_pcib.sc_tag,
155               PIIX4_PIRQRC);
156 
157           /* capture edge/level control registers */
158           sc->sc_elcr[0] = bus_space_read_1(sc->sc_iot, sc->sc_ioh, 0);
159           sc->sc_elcr[1] = bus_space_read_1(sc->sc_iot, sc->sc_ioh, 1);
160 
161           return true;
162 }
163 
164 static bool
piixpcib_resume(device_t dv,const pmf_qual_t * qual)165 piixpcib_resume(device_t dv, const pmf_qual_t *qual)
166 {
167           struct piixpcib_softc *sc = device_private(dv);
168 
169           /* restore PIRQX route control registers */
170           pci_conf_write(sc->sc_pcib.sc_pc, sc->sc_pcib.sc_tag, PIIX4_PIRQRC,
171               sc->sc_pirqrc);
172 
173           /* restore edge/level control registers */
174           bus_space_write_1(sc->sc_iot, sc->sc_ioh, 0, sc->sc_elcr[0]);
175           bus_space_write_1(sc->sc_iot, sc->sc_ioh, 1, sc->sc_elcr[1]);
176 
177           return true;
178 }
179 
180 /*
181  * Intel PIIX4 (SMI) SpeedStep support.
182  */
183 
184 #define PIIXPCIB_GSIC                   0x47534943
185 #define   PIIXPCIB_GETOWNER   0
186 #define   PIIXPCIB_GETSTATE   1
187 #define   PIIXPCIB_SETSTATE   2
188 #define   PIIXPCIB_GETFREQS   4
189 
190 #define   PIIXPCIB_SPEEDSTEP_HIGH       0
191 #define   PIIXPCIB_SPEEDSTEP_LOW        1
192 
193 static void
piixpcib_int15_gsic_call(int * sig,int * smicmd,int * cmd,int * smidata,int * flags)194 piixpcib_int15_gsic_call(int *sig, int *smicmd, int *cmd, int *smidata,
195     int *flags)
196 {
197           struct bioscallregs regs;
198 
199           /* No bioscall with EFI */
200           if (lookup_bootinfo(BTINFO_EFI) != NULL) {
201                     *sig = *smicmd = *cmd = *smidata = *flags = -1;
202                     return;
203           }
204 
205           memset(&regs, 0, sizeof(struct bioscallregs));
206           regs.EAX = 0x0000e980;        /* IST support */
207           regs.EDX = PIIXPCIB_GSIC;
208           bioscall(0x15, &regs);
209 
210           if (regs.EAX == PIIXPCIB_GSIC) {
211                     *sig = regs.EAX;
212                     *smicmd = regs.EBX & 0xff;
213                     *cmd = (regs.EBX >> 16) & 0xff;
214                     *smidata = regs.ECX;
215                     *flags = regs.EDX;
216           } else
217                     *sig = *smicmd = *cmd = *smidata = *flags = -1;
218 
219           return;
220 }
221 
222 static int
piixpcib_set_ownership(struct piixpcib_softc * sc)223 piixpcib_set_ownership(struct piixpcib_softc *sc)
224 {
225           int rv;
226           u_long pmagic;
227           static char magic[] = "Copyright (c) 1999 Intel Corporation";
228 
229           pmagic = vtophys((vaddr_t)magic);
230 
231           __asm__ __volatile__(
232               "movl $0, %%edi\n\t"
233               "out %%al, (%%dx)\n"
234               : "=D" (rv)
235               : "a" (sc->sc_command),
236                 "b" (0),
237                 "c" (0),
238                 "d" (sc->sc_smi_cmd),
239                 "S" (pmagic)
240           );
241 
242           return (rv ? ENXIO : 0);
243 }
244 
245 static int
piixpcib_getset_state(struct piixpcib_softc * sc,int * state,int function)246 piixpcib_getset_state(struct piixpcib_softc *sc, int *state, int function)
247 {
248           int new;
249           int rv;
250           int eax;
251 
252 #ifdef DIAGNOSTIC
253           if (function != PIIXPCIB_GETSTATE &&
254               function != PIIXPCIB_SETSTATE) {
255                     aprint_error_dev(sc->sc_dev,
256                         "GSI called with invalid function %d\n", function);
257                     return EINVAL;
258           }
259 #endif
260 
261           __asm__ __volatile__(
262               "movl $0, %%edi\n\t"
263               "out %%al, (%%dx)\n"
264               : "=a" (eax),
265                 "=b" (new),
266                 "=D" (rv)
267               : "a" (sc->sc_command),
268                 "b" (function),
269                 "c" (*state),
270                 "d" (sc->sc_smi_cmd),
271                 "S" (0)
272           );
273 
274           *state = new & 1;
275 
276           switch (function) {
277           case PIIXPCIB_GETSTATE:
278                     if (eax)
279                               return ENXIO;
280                     break;
281           case PIIXPCIB_SETSTATE:
282                     if (rv)
283                               return ENXIO;
284                     break;
285           }
286 
287           return 0;
288 }
289 
290 static int
piixpcib_get(struct piixpcib_softc * sc)291 piixpcib_get(struct piixpcib_softc *sc)
292 {
293           int rv;
294           int state;
295 
296           state = 0;          /* XXX gcc */
297 
298           rv = piixpcib_getset_state(sc, &state, PIIXPCIB_GETSTATE);
299           if (rv)
300                     return rv;
301 
302           return state & 1;
303 }
304 
305 static int
piixpcib_set(struct piixpcib_softc * sc,int state)306 piixpcib_set(struct piixpcib_softc *sc, int state)
307 {
308           int rv, s;
309           int try;
310 
311           if (state != PIIXPCIB_SPEEDSTEP_HIGH &&
312               state != PIIXPCIB_SPEEDSTEP_LOW)
313                     return ENXIO;
314           if (piixpcib_get(sc) == state)
315                     return 0;
316 
317           try = 5;
318 
319           s = splhigh();
320 
321           do {
322                     rv = piixpcib_getset_state(sc, &state, PIIXPCIB_SETSTATE);
323                     if (rv)
324                               delay(200);
325           } while (rv && --try);
326 
327           splx(s);
328 
329           return rv;
330 }
331 
332 static void
speedstep_configure(struct piixpcib_softc * sc,const struct pci_attach_args * pa)333 speedstep_configure(struct piixpcib_softc *sc,
334     const struct pci_attach_args *pa)
335 {
336           const struct sysctlnode       *node, *ssnode;
337           int sig, smicmd, cmd, smidata, flags;
338           int rv;
339 
340           piixpcib_int15_gsic_call(&sig, &smicmd, &cmd, &smidata, &flags);
341 
342           if (sig != -1) {
343                     sc->sc_smi_cmd = smicmd;
344                     sc->sc_smi_data = smidata;
345                     if (cmd == 0x80) {
346                               aprint_debug_dev(sc->sc_dev,
347                                   "GSIC returned cmd 0x80, should be 0x82\n");
348                               cmd = 0x82;
349                     }
350                     sc->sc_command = (sig & 0xffffff00) | (cmd & 0xff);
351                     sc->sc_flags = flags;
352           } else {
353                     /* setup some defaults */
354                     sc->sc_smi_cmd = 0xb2;
355                     sc->sc_smi_data = 0xb3;
356                     sc->sc_command = 0x47534982;
357                     sc->sc_flags = 0;
358           }
359 
360           if (piixpcib_set_ownership(sc) != 0) {
361                     aprint_error_dev(sc->sc_dev,
362                         "unable to claim ownership from the BIOS\n");
363                     return;   /* If we can't claim ownership from the BIOS, bail */
364           }
365 
366           /* Put in machdep.speedstep_state (0 for low, 1 for high). */
367           if ((rv = sysctl_createv(NULL, 0, NULL, &node,
368               CTLFLAG_PERMANENT, CTLTYPE_NODE, "machdep", NULL,
369               NULL, 0, NULL, 0, CTL_MACHDEP, CTL_EOL)) != 0)
370                     goto err;
371 
372           /* CTLFLAG_ANYWRITE? kernel option like EST? */
373           if ((rv = sysctl_createv(NULL, 0, &node, &ssnode,
374               CTLFLAG_READWRITE, CTLTYPE_INT, "speedstep_state", NULL,
375               speedstep_sysctl_helper, 0, NULL, 0, CTL_CREATE,
376               CTL_EOL)) != 0)
377                     goto err;
378 
379           /* XXX save the sc for IO tag/handle */
380           speedstep_cookie = sc;
381 
382           aprint_verbose_dev(sc->sc_dev, "SpeedStep SMI enabled\n");
383           return;
384 
385 err:
386           aprint_normal("%s: sysctl_createv failed (rv = %d)\n", __func__, rv);
387 }
388 
389 /*
390  * get/set the SpeedStep state: 0 == low power, 1 == high power.
391  */
392 static int
speedstep_sysctl_helper(SYSCTLFN_ARGS)393 speedstep_sysctl_helper(SYSCTLFN_ARGS)
394 {
395           struct sysctlnode node;
396           struct piixpcib_softc *sc;
397           uint8_t   state, state2;
398           int ostate, nstate, error;
399 
400           sc = speedstep_cookie;
401           error = 0;
402 
403           state = piixpcib_get(sc);
404           if (state == PIIXPCIB_SPEEDSTEP_HIGH)
405                     ostate = 1;
406           else
407                     ostate = 0;
408           nstate = ostate;
409 
410           node = *rnode;
411           node.sysctl_data = &nstate;
412 
413           error = sysctl_lookup(SYSCTLFN_CALL(&node));
414           if (error || newp == NULL)
415                     goto out;
416 
417           /* Only two states are available */
418           if (nstate != 0 && nstate != 1) {
419                     error = EINVAL;
420                     goto out;
421           }
422 
423           state2 = piixpcib_get(sc);
424           if (state2 == PIIXPCIB_SPEEDSTEP_HIGH)
425                     ostate = 1;
426           else
427                     ostate = 0;
428 
429           if (ostate != nstate)
430           {
431                     if (nstate == 0)
432                               state2 = PIIXPCIB_SPEEDSTEP_LOW;
433                     else
434                               state2 = PIIXPCIB_SPEEDSTEP_HIGH;
435 
436                     error = piixpcib_set(sc, state2);
437           }
438 out:
439           return (error);
440 }
441