1 /*-
2  * Copyright (c) 2019 Juniper Networks, Inc.
3  * Copyright (c) 2019 Semihalf.
4  * 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  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
19  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
23  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
24  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/rman.h>
36 #include <sys/systm.h>
37 
38 #include <dev/fdt/simplebus.h>
39 #include <dev/ofw/ofw_bus_subr.h>
40 #include <dev/ofw/ofw_bus.h>
41 
42 #include <machine/bus.h>
43 #include <machine/resource.h>
44 
45 #include "mdio_if.h"
46 
47 #define	REG_BASE_RID	0
48 
49 #define	MDIO_RATE_ADJ_EXT_OFFSET	0x000
50 #define	MDIO_RATE_ADJ_INT_OFFSET	0x004
51 #define	MDIO_RATE_ADJ_DIVIDENT_SHIFT	16
52 
53 #define	MDIO_SCAN_CTRL_OFFSET		0x008
54 #define	MDIO_SCAN_CTRL_OVRIDE_EXT_MSTR	28
55 
56 #define	MDIO_PARAM_OFFSET		0x23c
57 #define	MDIO_PARAM_MIIM_CYCLE		29
58 #define	MDIO_PARAM_INTERNAL_SEL		25
59 #define	MDIO_PARAM_BUS_ID		22
60 #define	MDIO_PARAM_C45_SEL		21
61 #define	MDIO_PARAM_PHY_ID		16
62 #define	MDIO_PARAM_PHY_DATA		0
63 
64 #define	MDIO_READ_OFFSET		0x240
65 #define	MDIO_READ_DATA_MASK		0xffff
66 #define	MDIO_ADDR_OFFSET		0x244
67 
68 #define	MDIO_CTRL_OFFSET		0x248
69 #define	MDIO_CTRL_WRITE_OP		0x1
70 #define	MDIO_CTRL_READ_OP		0x2
71 
72 #define	MDIO_STAT_OFFSET		0x24c
73 #define	MDIO_STAT_DONE			1
74 
75 #define	BUS_MAX_ADDR			32
76 #define	EXT_BUS_START_ADDR		16
77 
78 #define	MDIO_REG_ADDR_SPACE_SIZE	0x250
79 
80 #define	MDIO_OPERATING_FREQUENCY	11000000
81 #define	MDIO_RATE_ADJ_DIVIDENT		1
82 
83 #define	MII_ADDR_C45			(1<<30)
84 
85 static int brcm_iproc_mdio_probe(device_t);
86 static int brcm_iproc_mdio_attach(device_t);
87 static int brcm_iproc_mdio_detach(device_t);
88 
89 /* OFW bus interface */
90 struct brcm_mdio_ofw_devinfo {
91 	struct ofw_bus_devinfo	di_dinfo;
92 	struct resource_list	di_rl;
93 };
94 
95 struct brcm_iproc_mdio_softc {
96 	struct simplebus_softc	sbus;
97 	device_t		dev;
98 	struct resource *	reg_base;
99 	uint32_t		clock_rate;
100 };
101 
102 MALLOC_DEFINE(M_BRCM_IPROC_MDIO, "Broadcom IPROC MDIO",
103     "Broadcom IPROC MDIO dynamic memory");
104 
105 static int brcm_iproc_config(struct brcm_iproc_mdio_softc*);
106 static const struct ofw_bus_devinfo *
107 brcm_iproc_mdio_get_devinfo(device_t, device_t);
108 static int brcm_iproc_mdio_write_mux(device_t, int, int, int, int);
109 static int brcm_iproc_mdio_read_mux(device_t, int, int, int);
110 
111 static device_method_t brcm_iproc_mdio_fdt_methods[] = {
112 	/* Device interface */
113 	DEVMETHOD(device_probe,		brcm_iproc_mdio_probe),
114 	DEVMETHOD(device_attach,	brcm_iproc_mdio_attach),
115 	DEVMETHOD(device_detach,	brcm_iproc_mdio_detach),
116 
117 	/* Bus interface */
118 	DEVMETHOD(bus_alloc_resource,		bus_generic_alloc_resource),
119 	DEVMETHOD(bus_release_resource,		bus_generic_release_resource),
120 	DEVMETHOD(bus_activate_resource,	bus_generic_activate_resource),
121 
122 	/* ofw_bus interface */
123 	DEVMETHOD(ofw_bus_get_devinfo,	brcm_iproc_mdio_get_devinfo),
124 	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
125 	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
126 	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
127 	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
128 	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
129 
130 	/* MDIO interface */
131 	DEVMETHOD(mdio_writereg_mux,	brcm_iproc_mdio_write_mux),
132 	DEVMETHOD(mdio_readreg_mux,	brcm_iproc_mdio_read_mux),
133 
134 	/* End */
135 	DEVMETHOD_END
136 };
137 
138 DEFINE_CLASS_0(brcm_iproc_mdio, brcm_iproc_mdio_driver,
139     brcm_iproc_mdio_fdt_methods, sizeof(struct brcm_iproc_mdio_softc));
140 
141 static devclass_t brcm_iproc_mdio_fdt_devclass;
142 
143 EARLY_DRIVER_MODULE(brcm_iproc_mdio, ofwbus, brcm_iproc_mdio_driver,
144     brcm_iproc_mdio_fdt_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
145 EARLY_DRIVER_MODULE(brcm_iproc_mdio, simplebus, brcm_iproc_mdio_driver,
146     brcm_iproc_mdio_fdt_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
147 
148 static struct ofw_compat_data mdio_compat_data[] = {
149 	{"brcm,mdio-mux-iproc",	true},
150 	{NULL,			false}
151 };
152 
153 static int
154 brcm_iproc_switch(struct brcm_iproc_mdio_softc *sc, int child)
155 {
156 	uint32_t param, bus_id;
157 	uint32_t bus_dir;
158 
159 	/* select bus and its properties */
160 	bus_dir = (child < EXT_BUS_START_ADDR);
161 	bus_id = bus_dir ? child : (child - EXT_BUS_START_ADDR);
162 
163 	param = (bus_dir ? 1 : 0) << MDIO_PARAM_INTERNAL_SEL;
164 	param |= (bus_id << MDIO_PARAM_BUS_ID);
165 
166 	bus_write_4(sc->reg_base, MDIO_PARAM_OFFSET, param);
167 
168 	return (0);
169 }
170 
171 static int
172 iproc_mdio_wait_for_idle(struct brcm_iproc_mdio_softc *sc, uint32_t result)
173 {
174 	unsigned int timeout = 1000; /* loop for 1s */
175 	uint32_t val;
176 
177 	do {
178 		val = bus_read_4(sc->reg_base, MDIO_STAT_OFFSET);
179 		if ((val & MDIO_STAT_DONE) == result)
180 			return (0);
181 
182 		pause("BRCM MDIO SLEEP", 1000 / hz);
183 	} while (timeout--);
184 
185 	return (ETIMEDOUT);
186 }
187 
188 /* start_miim_ops- Program and start MDIO transaction over mdio bus.
189  * @base: Base address
190  * @phyid: phyid of the selected bus.
191  * @reg: register offset to be read/written.
192  * @val :0 if read op else value to be written in @reg;
193  * @op: Operation that need to be carried out.
194  *      MDIO_CTRL_READ_OP: Read transaction.
195  *      MDIO_CTRL_WRITE_OP: Write transaction.
196  *
197  * Return value: Successful Read operation returns read reg values and write
198  *      operation returns 0. Failure operation returns negative error code.
199  */
200 static int
201 brcm_iproc_mdio_op(struct brcm_iproc_mdio_softc *sc,
202 	uint16_t phyid, uint32_t reg, uint32_t val, uint32_t op)
203 {
204 	uint32_t param;
205 	int ret;
206 
207 	bus_write_4(sc->reg_base, MDIO_CTRL_OFFSET, 0);
208 	bus_read_4(sc->reg_base, MDIO_STAT_OFFSET);
209 	ret = iproc_mdio_wait_for_idle(sc, 0);
210 	if (ret)
211 		goto err;
212 
213 	param = bus_read_4(sc->reg_base, MDIO_PARAM_OFFSET);
214 	param |= phyid << MDIO_PARAM_PHY_ID;
215 	param |= val << MDIO_PARAM_PHY_DATA;
216 	if (reg & MII_ADDR_C45)
217 		param |= (1 << MDIO_PARAM_C45_SEL);
218 
219 	bus_write_4(sc->reg_base, MDIO_PARAM_OFFSET, param);
220 
221 	bus_write_4(sc->reg_base, MDIO_ADDR_OFFSET, reg);
222 
223 	bus_write_4(sc->reg_base, MDIO_CTRL_OFFSET, op);
224 
225 	ret = iproc_mdio_wait_for_idle(sc, 1);
226 	if (ret)
227 		goto err;
228 
229 	if (op == MDIO_CTRL_READ_OP)
230 		ret = bus_read_4(sc->reg_base, MDIO_READ_OFFSET) & MDIO_READ_DATA_MASK;
231 err:
232 	return ret;
233 }
234 
235 static int
236 brcm_iproc_config(struct brcm_iproc_mdio_softc *sc)
237 {
238 	uint32_t divisor;
239 	uint32_t val;
240 
241 	/* Disable external mdio master access */
242 	val = bus_read_4(sc->reg_base, MDIO_SCAN_CTRL_OFFSET);
243 	val |= 1 << MDIO_SCAN_CTRL_OVRIDE_EXT_MSTR;
244 	bus_write_4(sc->reg_base, MDIO_SCAN_CTRL_OFFSET, val);
245 
246 	if (sc->clock_rate) {
247 		/* use rate adjust regs to derrive the mdio's operating
248 		 * frequency from the specified core clock
249 		 */
250 		divisor = sc->clock_rate / MDIO_OPERATING_FREQUENCY;
251 		divisor = divisor / (MDIO_RATE_ADJ_DIVIDENT + 1);
252 		val = divisor;
253 		val |= MDIO_RATE_ADJ_DIVIDENT << MDIO_RATE_ADJ_DIVIDENT_SHIFT;
254 		bus_write_4(sc->reg_base, MDIO_RATE_ADJ_EXT_OFFSET, val);
255 		bus_write_4(sc->reg_base, MDIO_RATE_ADJ_INT_OFFSET, val);
256 	}
257 
258 	return (0);
259 }
260 
261 static int
262 brcm_iproc_mdio_write_mux(device_t dev, int bus, int phy, int reg, int val)
263 {
264 	struct brcm_iproc_mdio_softc *sc;
265 
266 	sc = device_get_softc(dev);
267 
268 	if (brcm_iproc_switch(sc, bus) != 0) {
269 		device_printf(dev, "Failed to set BUS MUX\n");
270 		return (EINVAL);
271 	}
272 
273 	return (brcm_iproc_mdio_op(sc, phy, reg, val, MDIO_CTRL_WRITE_OP));
274 }
275 
276 static int
277 brcm_iproc_mdio_read_mux(device_t dev, int bus, int phy, int reg)
278 {
279 	struct brcm_iproc_mdio_softc *sc;
280 
281 	sc = device_get_softc(dev);
282 
283 	if (brcm_iproc_switch(sc, bus) != 0) {
284 		device_printf(dev, "Failed to set BUS MUX\n");
285 		return (EINVAL);
286 	}
287 
288 	return (brcm_iproc_mdio_op(sc, phy, reg, 0, MDIO_CTRL_READ_OP));
289 }
290 
291 static int
292 brcm_iproc_mdio_probe(device_t dev)
293 {
294 
295 	if (!ofw_bus_status_okay(dev))
296 		return (ENXIO);
297 	if (!ofw_bus_search_compatible(dev, mdio_compat_data)->ocd_data)
298 		return (ENXIO);
299 
300 	device_set_desc(dev, "Broadcom MDIO MUX driver");
301 	return (BUS_PROBE_DEFAULT);
302 }
303 
304 static int
305 brcm_iproc_mdio_attach(device_t dev)
306 {
307 	struct brcm_iproc_mdio_softc *sc;
308 	phandle_t node, parent;
309 	struct brcm_mdio_ofw_devinfo *di;
310 	int rid;
311 	device_t child;
312 
313 	sc = device_get_softc(dev);
314 	sc->dev = dev;
315 
316 	/* Allocate memory resources */
317 	rid = REG_BASE_RID;
318 	sc->reg_base = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
319 	    RF_ACTIVE);
320 	if (sc->reg_base == NULL) {
321 		device_printf(dev, "Could not allocate memory\n");
322 		return (ENXIO);
323 	}
324 
325 	/* Configure MDIO controlled */
326 	if (brcm_iproc_config(sc) < 0) {
327 		device_printf(dev, "Unable to initialize IPROC MDIO\n");
328 		goto error;
329 	}
330 
331 	parent = ofw_bus_get_node(dev);
332 	simplebus_init(dev, parent);
333 
334 	/* Iterate through all bus subordinates */
335 	for (node = OF_child(parent); node > 0; node = OF_peer(node)) {
336 		/* Allocate and populate devinfo. */
337 		di = malloc(sizeof(*di), M_BRCM_IPROC_MDIO, M_WAITOK | M_ZERO);
338 		if (ofw_bus_gen_setup_devinfo(&di->di_dinfo, node) != 0) {
339 			free(di, M_BRCM_IPROC_MDIO);
340 			continue;
341 		}
342 
343 		/* Initialize and populate resource list. */
344 		resource_list_init(&di->di_rl);
345 		ofw_bus_reg_to_rl(dev, node, sc->sbus.acells, sc->sbus.scells,
346 		    &di->di_rl);
347 		ofw_bus_intr_to_rl(dev, node, &di->di_rl, NULL);
348 
349 		/* Add newbus device for this FDT node */
350 		child = device_add_child(dev, NULL, -1);
351 		if (child == NULL) {
352 			printf("Failed to add child\n");
353 			resource_list_free(&di->di_rl);
354 			ofw_bus_gen_destroy_devinfo(&di->di_dinfo);
355 			free(di, M_BRCM_IPROC_MDIO);
356 			continue;
357 		}
358 
359 		device_set_ivars(child, di);
360 	}
361 
362 	/*
363 	 * Register device to this node/xref.
364 	 * Thanks to that we will be able to retrieve device_t structure
365 	 * while holding only node reference acquired from FDT.
366 	 */
367 	node = ofw_bus_get_node(dev);
368 	OF_device_register_xref(OF_xref_from_node(node), dev);
369 
370 	return (bus_generic_attach(dev));
371 
372 error:
373 	brcm_iproc_mdio_detach(dev);
374 	return (ENXIO);
375 }
376 
377 static const struct ofw_bus_devinfo *
378 brcm_iproc_mdio_get_devinfo(device_t bus __unused, device_t child)
379 {
380 	struct brcm_mdio_ofw_devinfo *di;
381 
382 	di = device_get_ivars(child);
383 	return (&di->di_dinfo);
384 }
385 
386 static int
387 brcm_iproc_mdio_detach(device_t dev)
388 {
389 	struct brcm_iproc_mdio_softc *sc;
390 
391 	sc = device_get_softc(dev);
392 
393 	if (sc->reg_base != NULL) {
394 		bus_release_resource(dev, SYS_RES_MEMORY, REG_BASE_RID,
395 		    sc->reg_base);
396 	}
397 
398 	return (0);
399 }
400