xref: /freebsd/sys/powerpc/powermac/grackle.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
1 /*-
2  * Copyright 2003 by Peter Grehan. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/module.h>
34 #include <sys/bus.h>
35 #include <sys/conf.h>
36 #include <sys/kernel.h>
37 #include <sys/proc.h>
38 
39 #include <dev/ofw/openfirm.h>
40 #include <dev/ofw/ofw_pci.h>
41 #include <dev/ofw/ofw_bus.h>
42 #include <dev/ofw/ofw_bus_subr.h>
43 
44 #include <dev/pci/pcivar.h>
45 #include <dev/pci/pcireg.h>
46 
47 #include <machine/bus.h>
48 #include <machine/intr_machdep.h>
49 #include <machine/md_var.h>
50 #include <machine/pio.h>
51 #include <machine/resource.h>
52 
53 #include <sys/rman.h>
54 
55 #include <powerpc/ofw/ofw_pci.h>
56 #include <powerpc/powermac/gracklevar.h>
57 
58 #include <vm/vm.h>
59 #include <vm/pmap.h>
60 
61 #include "pcib_if.h"
62 
63 /*
64  * Device interface.
65  */
66 static int		grackle_probe(device_t);
67 static int		grackle_attach(device_t);
68 
69 /*
70  * pcib interface.
71  */
72 static u_int32_t	grackle_read_config(device_t, u_int, u_int, u_int,
73 			    u_int, int);
74 static void		grackle_write_config(device_t, u_int, u_int, u_int,
75 			    u_int, u_int32_t, int);
76 
77 /*
78  * Local routines.
79  */
80 static int		grackle_enable_config(struct grackle_softc *, u_int,
81 			    u_int, u_int, u_int);
82 static void		grackle_disable_config(struct grackle_softc *);
83 static int		badaddr(void *, size_t);
84 
85 /*
86  * Driver methods.
87  */
88 static device_method_t	grackle_methods[] = {
89 	/* Device interface */
90 	DEVMETHOD(device_probe,		grackle_probe),
91 	DEVMETHOD(device_attach,	grackle_attach),
92 
93 	/* pcib interface */
94 	DEVMETHOD(pcib_read_config,	grackle_read_config),
95 	DEVMETHOD(pcib_write_config,	grackle_write_config),
96 
97 	DEVMETHOD_END
98 };
99 
100 static devclass_t	grackle_devclass;
101 DEFINE_CLASS_1(pcib, grackle_driver, grackle_methods,
102     sizeof(struct grackle_softc), ofw_pci_driver);
103 DRIVER_MODULE(grackle, ofwbus, grackle_driver, grackle_devclass, 0, 0);
104 
105 static int
106 grackle_probe(device_t dev)
107 {
108 	const char	*type, *compatible;
109 
110 	type = ofw_bus_get_type(dev);
111 	compatible = ofw_bus_get_compat(dev);
112 
113 	if (type == NULL || compatible == NULL)
114 		return (ENXIO);
115 
116 	if (strcmp(type, "pci") != 0 || strcmp(compatible, "grackle") != 0)
117 		return (ENXIO);
118 
119 	device_set_desc(dev, "MPC106 (Grackle) Host-PCI bridge");
120 	return (0);
121 }
122 
123 static int
124 grackle_attach(device_t dev)
125 {
126 	struct		grackle_softc *sc;
127 
128 	sc = device_get_softc(dev);
129 
130 	/*
131 	 * The Grackle PCI config addr/data registers are actually in
132 	 * PCI space, but since they are needed to actually probe the
133 	 * PCI bus, use the fact that they are also available directly
134 	 * on the processor bus and map them
135 	 */
136 	sc->sc_addr = (vm_offset_t)pmap_mapdev(GRACKLE_ADDR, PAGE_SIZE);
137 	sc->sc_data = (vm_offset_t)pmap_mapdev(GRACKLE_DATA, PAGE_SIZE);
138 
139 	return (ofw_pci_attach(dev));
140 }
141 
142 static u_int32_t
143 grackle_read_config(device_t dev, u_int bus, u_int slot, u_int func, u_int reg,
144     int width)
145 {
146 	struct		grackle_softc *sc;
147 	vm_offset_t	caoff;
148 	u_int32_t	retval = 0xffffffff;
149 
150 	sc = device_get_softc(dev);
151 	caoff = sc->sc_data + (reg & 0x03);
152 
153 	if (grackle_enable_config(sc, bus, slot, func, reg) != 0) {
154 
155 		/*
156 		 * Config probes to non-existent devices on the
157 		 * secondary bus generates machine checks. Be sure
158 		 * to catch these.
159 		 */
160 		if (bus > 0) {
161 		  if (badaddr((void *)sc->sc_data, 4)) {
162 			  return (retval);
163 		  }
164 		}
165 
166 		switch (width) {
167 		case 1:
168 			retval = (in8rb(caoff));
169 			break;
170 		case 2:
171 			retval = (in16rb(caoff));
172 			break;
173 		case 4:
174 			retval = (in32rb(caoff));
175 			break;
176 		}
177 	}
178 	grackle_disable_config(sc);
179 
180 	return (retval);
181 }
182 
183 static void
184 grackle_write_config(device_t dev, u_int bus, u_int slot, u_int func,
185     u_int reg, u_int32_t val, int width)
186 {
187 	struct		grackle_softc *sc;
188 	vm_offset_t	caoff;
189 
190 	sc = device_get_softc(dev);
191 	caoff = sc->sc_data + (reg & 0x03);
192 
193 	if (grackle_enable_config(sc, bus, slot, func, reg)) {
194 		switch (width) {
195 		case 1:
196 			out8rb(caoff, val);
197 			(void)in8rb(caoff);
198 			break;
199 		case 2:
200 			out16rb(caoff, val);
201 			(void)in16rb(caoff);
202 			break;
203 		case 4:
204 			out32rb(caoff, val);
205 			(void)in32rb(caoff);
206 			break;
207 		}
208 	}
209 	grackle_disable_config(sc);
210 }
211 
212 static int
213 grackle_enable_config(struct grackle_softc *sc, u_int bus, u_int slot,
214     u_int func, u_int reg)
215 {
216 	u_int32_t	cfgval;
217 
218 	/*
219 	 * Unlike UniNorth, the format of the config word is the same
220 	 * for local (0) and remote busses.
221 	 */
222 	cfgval = (bus << 16) | (slot << 11) | (func << 8) | (reg & 0xFC)
223 	    | GRACKLE_CFG_ENABLE;
224 
225 	out32rb(sc->sc_addr, cfgval);
226 	(void) in32rb(sc->sc_addr);
227 
228 	return (1);
229 }
230 
231 static void
232 grackle_disable_config(struct grackle_softc *sc)
233 {
234 	/*
235 	 * Clear the GRACKLE_CFG_ENABLE bit to prevent stray
236 	 * accesses from causing config cycles
237 	 */
238 	out32rb(sc->sc_addr, 0);
239 }
240 
241 static int
242 badaddr(void *addr, size_t size)
243 {
244 	struct thread	*td;
245 	jmp_buf		env, *oldfaultbuf;
246 	int		x;
247 
248 	/* Get rid of any stale machine checks that have been waiting.  */
249 	__asm __volatile ("sync; isync");
250 
251 	td = curthread;
252 
253 	oldfaultbuf = td->td_pcb->pcb_onfault;
254 	td->td_pcb->pcb_onfault = &env;
255 	if (setjmp(env)) {
256 		td->td_pcb->pcb_onfault = oldfaultbuf;
257 		__asm __volatile ("sync");
258 		return 1;
259 	}
260 
261 	__asm __volatile ("sync");
262 
263 	switch (size) {
264 	case 1:
265 		x = *(volatile int8_t *)addr;
266 		break;
267 	case 2:
268 		x = *(volatile int16_t *)addr;
269 		break;
270 	case 4:
271 		x = *(volatile int32_t *)addr;
272 		break;
273 	default:
274 		panic("badaddr: invalid size (%zd)", size);
275 	}
276 
277 	/* Make sure we took the machine check, if we caused one. */
278 	__asm __volatile ("sync; isync");
279 
280 	td->td_pcb->pcb_onfault = oldfaultbuf;
281 	__asm __volatile ("sync");	/* To be sure. */
282 
283 	return (0);
284 }
285 
286 /*
287  * Driver to swallow Grackle host bridges from the PCI bus side.
288  */
289 static int
290 grackle_hb_probe(device_t dev)
291 {
292 
293 	if (pci_get_devid(dev) == 0x00021057) {
294 		device_set_desc(dev, "Grackle Host to PCI bridge");
295 		device_quiet(dev);
296 		return (0);
297 	}
298 
299 	return (ENXIO);
300 }
301 
302 static int
303 grackle_hb_attach(device_t dev)
304 {
305 
306 	return (0);
307 }
308 
309 static device_method_t grackle_hb_methods[] = {
310 	/* Device interface */
311 	DEVMETHOD(device_probe,         grackle_hb_probe),
312 	DEVMETHOD(device_attach,        grackle_hb_attach),
313 
314 	{ 0, 0 }
315 };
316 
317 static driver_t grackle_hb_driver = {
318 	"grackle_hb",
319 	grackle_hb_methods,
320 	1,
321 };
322 static devclass_t grackle_hb_devclass;
323 
324 DRIVER_MODULE(grackle_hb, pci, grackle_hb_driver, grackle_hb_devclass, 0, 0);
325