1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright 2003 by Peter Grehan. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
22 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/module.h>
36#include <sys/bus.h>
37#include <sys/conf.h>
38#include <sys/kernel.h>
39#include <sys/proc.h>
40#include <sys/rman.h>
41
42#include <dev/ofw/openfirm.h>
43#include <dev/ofw/ofw_pci.h>
44#include <dev/ofw/ofw_bus.h>
45#include <dev/ofw/ofw_bus_subr.h>
46#include <dev/ofw/ofwpci.h>
47
48#include <dev/pci/pcivar.h>
49#include <dev/pci/pcireg.h>
50
51#include <machine/bus.h>
52#include <machine/intr_machdep.h>
53#include <machine/md_var.h>
54#include <machine/pio.h>
55#include <machine/resource.h>
56
57#include <powerpc/powermac/gracklevar.h>
58
59#include <vm/vm.h>
60#include <vm/pmap.h>
61
62#include "pcib_if.h"
63
64/*
65 * Device interface.
66 */
67static int		grackle_probe(device_t);
68static int		grackle_attach(device_t);
69
70/*
71 * pcib interface.
72 */
73static u_int32_t	grackle_read_config(device_t, u_int, u_int, u_int,
74			    u_int, int);
75static void		grackle_write_config(device_t, u_int, u_int, u_int,
76			    u_int, u_int32_t, int);
77
78/*
79 * Local routines.
80 */
81static int		grackle_enable_config(struct grackle_softc *, u_int,
82			    u_int, u_int, u_int);
83static void		grackle_disable_config(struct grackle_softc *);
84static int		badaddr(void *, size_t);
85
86/*
87 * Driver methods.
88 */
89static device_method_t	grackle_methods[] = {
90	/* Device interface */
91	DEVMETHOD(device_probe,		grackle_probe),
92	DEVMETHOD(device_attach,	grackle_attach),
93
94	/* pcib interface */
95	DEVMETHOD(pcib_read_config,	grackle_read_config),
96	DEVMETHOD(pcib_write_config,	grackle_write_config),
97
98	DEVMETHOD_END
99};
100
101static devclass_t	grackle_devclass;
102DEFINE_CLASS_1(pcib, grackle_driver, grackle_methods,
103    sizeof(struct grackle_softc), ofw_pci_driver);
104DRIVER_MODULE(grackle, ofwbus, grackle_driver, grackle_devclass, 0, 0);
105
106static int
107grackle_probe(device_t dev)
108{
109	const char	*type, *compatible;
110
111	type = ofw_bus_get_type(dev);
112	compatible = ofw_bus_get_compat(dev);
113
114	if (type == NULL || compatible == NULL)
115		return (ENXIO);
116
117	if (strcmp(type, "pci") != 0 || strcmp(compatible, "grackle") != 0)
118		return (ENXIO);
119
120	device_set_desc(dev, "MPC106 (Grackle) Host-PCI bridge");
121	return (0);
122}
123
124static int
125grackle_attach(device_t dev)
126{
127	struct		grackle_softc *sc;
128
129	sc = device_get_softc(dev);
130
131	/*
132	 * The Grackle PCI config addr/data registers are actually in
133	 * PCI space, but since they are needed to actually probe the
134	 * PCI bus, use the fact that they are also available directly
135	 * on the processor bus and map them
136	 */
137	sc->sc_addr = (vm_offset_t)pmap_mapdev(GRACKLE_ADDR, PAGE_SIZE);
138	sc->sc_data = (vm_offset_t)pmap_mapdev(GRACKLE_DATA, PAGE_SIZE);
139
140	return (ofw_pci_attach(dev));
141}
142
143static u_int32_t
144grackle_read_config(device_t dev, u_int bus, u_int slot, u_int func, u_int reg,
145    int width)
146{
147	struct		grackle_softc *sc;
148	vm_offset_t	caoff;
149	u_int32_t	retval = 0xffffffff;
150
151	sc = device_get_softc(dev);
152	caoff = sc->sc_data + (reg & 0x03);
153
154	if (grackle_enable_config(sc, bus, slot, func, reg) != 0) {
155
156		/*
157		 * Config probes to non-existent devices on the
158		 * secondary bus generates machine checks. Be sure
159		 * to catch these.
160		 */
161		if (bus > 0) {
162		  if (badaddr((void *)sc->sc_data, 4)) {
163			  return (retval);
164		  }
165		}
166
167		switch (width) {
168		case 1:
169			retval = (in8rb(caoff));
170			break;
171		case 2:
172			retval = (in16rb(caoff));
173			break;
174		case 4:
175			retval = (in32rb(caoff));
176			break;
177		}
178	}
179	grackle_disable_config(sc);
180
181	return (retval);
182}
183
184static void
185grackle_write_config(device_t dev, u_int bus, u_int slot, u_int func,
186    u_int reg, u_int32_t val, int width)
187{
188	struct		grackle_softc *sc;
189	vm_offset_t	caoff;
190
191	sc = device_get_softc(dev);
192	caoff = sc->sc_data + (reg & 0x03);
193
194	if (grackle_enable_config(sc, bus, slot, func, reg)) {
195		switch (width) {
196		case 1:
197			out8rb(caoff, val);
198			(void)in8rb(caoff);
199			break;
200		case 2:
201			out16rb(caoff, val);
202			(void)in16rb(caoff);
203			break;
204		case 4:
205			out32rb(caoff, val);
206			(void)in32rb(caoff);
207			break;
208		}
209	}
210	grackle_disable_config(sc);
211}
212
213static int
214grackle_enable_config(struct grackle_softc *sc, u_int bus, u_int slot,
215    u_int func, u_int reg)
216{
217	u_int32_t	cfgval;
218
219	/*
220	 * Unlike UniNorth, the format of the config word is the same
221	 * for local (0) and remote busses.
222	 */
223	cfgval = (bus << 16) | (slot << 11) | (func << 8) | (reg & 0xFC)
224	    | GRACKLE_CFG_ENABLE;
225
226	out32rb(sc->sc_addr, cfgval);
227	(void) in32rb(sc->sc_addr);
228
229	return (1);
230}
231
232static void
233grackle_disable_config(struct grackle_softc *sc)
234{
235	/*
236	 * Clear the GRACKLE_CFG_ENABLE bit to prevent stray
237	 * accesses from causing config cycles
238	 */
239	out32rb(sc->sc_addr, 0);
240}
241
242static int
243badaddr(void *addr, size_t size)
244{
245	struct thread	*td;
246	jmp_buf		env, *oldfaultbuf;
247	int		x;
248
249	/* Get rid of any stale machine checks that have been waiting.  */
250	__asm __volatile ("sync; isync");
251
252	td = curthread;
253
254	oldfaultbuf = td->td_pcb->pcb_onfault;
255	td->td_pcb->pcb_onfault = &env;
256	if (setjmp(env)) {
257		td->td_pcb->pcb_onfault = oldfaultbuf;
258		__asm __volatile ("sync");
259		return 1;
260	}
261
262	__asm __volatile ("sync");
263
264	switch (size) {
265	case 1:
266		x = *(volatile int8_t *)addr;
267		break;
268	case 2:
269		x = *(volatile int16_t *)addr;
270		break;
271	case 4:
272		x = *(volatile int32_t *)addr;
273		break;
274	default:
275		panic("badaddr: invalid size (%zd)", size);
276	}
277
278	/* Make sure we took the machine check, if we caused one. */
279	__asm __volatile ("sync; isync");
280
281	td->td_pcb->pcb_onfault = oldfaultbuf;
282	__asm __volatile ("sync");	/* To be sure. */
283
284	return (0);
285}
286
287/*
288 * Driver to swallow Grackle host bridges from the PCI bus side.
289 */
290static int
291grackle_hb_probe(device_t dev)
292{
293
294	if (pci_get_devid(dev) == 0x00021057) {
295		device_set_desc(dev, "Grackle Host to PCI bridge");
296		device_quiet(dev);
297		return (0);
298	}
299
300	return (ENXIO);
301}
302
303static int
304grackle_hb_attach(device_t dev)
305{
306
307	return (0);
308}
309
310static device_method_t grackle_hb_methods[] = {
311	/* Device interface */
312	DEVMETHOD(device_probe,         grackle_hb_probe),
313	DEVMETHOD(device_attach,        grackle_hb_attach),
314
315	{ 0, 0 }
316};
317
318static driver_t grackle_hb_driver = {
319	"grackle_hb",
320	grackle_hb_methods,
321	1,
322};
323static devclass_t grackle_hb_devclass;
324
325DRIVER_MODULE(grackle_hb, pci, grackle_hb_driver, grackle_hb_devclass, 0, 0);
326