xref: /netbsd-src/sys/arch/arm/gemini/gemini_gmac.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /* $NetBSD: gemini_gmac.c,v 1.21 2021/04/24 23:36:27 thorpej Exp $ */
2 /*-
3  * Copyright (c) 2008 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Matt Thomas <matt@3am-software.com>
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include "locators.h"
32 #include <sys/param.h>
33 #include <sys/device.h>
34 #include <sys/kmem.h>
35 #include <sys/mbuf.h>
36 
37 #include <net/if.h>
38 #include <net/if_ether.h>
39 
40 #include <sys/bus.h>
41 
42 #include <arm/gemini/gemini_reg.h>
43 #include <arm/gemini/gemini_obiovar.h>
44 #include <arm/gemini/gemini_gmacvar.h>
45 #include <arm/gemini/gemini_gpiovar.h>
46 
47 #include <dev/mii/mii.h>
48 #include <dev/mii/mii_bitbang.h>
49 
50 #include <sys/gpio.h>
51 
52 __KERNEL_RCSID(0, "$NetBSD: gemini_gmac.c,v 1.21 2021/04/24 23:36:27 thorpej Exp $");
53 
54 #define	SWFREEQ_DESCS	256	/* one page worth */
55 #define	HWFREEQ_DESCS	256	/* one page worth */
56 
57 static int geminigmac_match(device_t, cfdata_t, void *);
58 static void geminigmac_attach(device_t, device_t, void *);
59 static int geminigmac_find(device_t, cfdata_t, const int *, void *);
60 static int geminigmac_print(void *aux, const char *name);
61 
62 static int geminigmac_mii_readreg(device_t, int, int, uint16_t *);
63 static int geminigmac_mii_writereg(device_t, int, int, uint16_t);
64 
65 #define	GPIO_MDIO	21
66 #define	GPIO_MDCLK	22
67 
68 #define	MDIN		__BIT(3)
69 #define	MDOUT		__BIT(2)
70 #define	MDCLK		__BIT(1)
71 #define	MDTOPHY		__BIT(0)
72 
73 CFATTACH_DECL_NEW(geminigmac, sizeof(struct gmac_softc),
74     geminigmac_match, geminigmac_attach, NULL, NULL);
75 
76 extern struct cfdriver geminigmac_cd;
77 extern struct cfdriver geminigpio_cd;
78 
79 void
80 gmac_swfree_min_update(struct gmac_softc *sc)
81 {
82 	uint32_t v;
83 
84 	if (sc->sc_swfreeq != NULL
85 	    && sc->sc_swfree_min > sc->sc_swfreeq->hwq_size - 1)
86 		sc->sc_swfree_min = sc->sc_swfreeq->hwq_size - 1;
87 
88 	v = bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_QFE_THRESHOLD);
89 	v &= ~QFE_SWFQ_THRESHOLD_MASK;
90 	v |= QFE_SWFQ_THRESHOLD(sc->sc_swfree_min);
91 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_QFE_THRESHOLD, v);
92 }
93 
94 void
95 gmac_intr_update(struct gmac_softc *sc)
96 {
97 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT0_MASK,
98 	    ~sc->sc_int_enabled[0]);
99 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT1_MASK,
100 	    ~sc->sc_int_enabled[1]);
101 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT2_MASK,
102 	    ~sc->sc_int_enabled[2]);
103 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT3_MASK,
104 	    ~sc->sc_int_enabled[3]);
105 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT4_MASK,
106 	    ~sc->sc_int_enabled[4]);
107 }
108 
109 static void
110 gmac_init(struct gmac_softc *sc)
111 {
112 	gmac_hwqmem_t *hqm;
113 
114 	/*
115 	 * This shouldn't be needed.
116 	 */
117 	for (bus_size_t i = 0; i < GMAC_TOE_QH_SIZE; i += 4) {
118 		bus_space_write_4(sc->sc_iot, sc->sc_ioh,
119 		    GMAC_TOE_QH_OFFSET + i, 0);
120 	}
121 #if 0
122 	{
123 	bus_space_handle_t global_ioh;
124 	int error;
125 
126 	error = bus_space_map(sc->sc_iot, GEMINI_GLOBAL_BASE, 4, 0,
127 	    &global_ioh);
128 	KASSERT(error == 0);
129 	aprint_normal_dev(sc->sc_dev, "gmac_init: global_ioh=%#zx\n", global_ioh);
130 	bus_space_write_4(sc->sc_iot, global_ioh, GEMINI_GLOBAL_RESET_CTL,
131 	    GLOBAL_RESET_GMAC0|GLOBAL_RESET_GMAC1);
132 	do {
133 		v = bus_space_read_4(sc->sc_iot, global_ioh,
134 		    GEMINI_GLOBAL_RESET_CTL);
135 	} while (v & (GLOBAL_RESET_GMAC0|GLOBAL_RESET_GMAC1));
136 	bus_space_unmap(sc->sc_iot, global_ioh, 4);
137 	DELAY(1000);
138 	}
139 #endif
140 
141 	sc->sc_swfree_min = 4; /* MIN_RXMAPS; */
142 
143 	gmac_swfree_min_update(sc);
144 
145 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_SKBSIZE,
146 	    SKB_SIZE_SET(PAGE_SIZE, MCLBYTES));
147 
148 	sc->sc_int_select[0] = INT0_GMAC1;
149 	sc->sc_int_select[1] = INT1_GMAC1;
150 	sc->sc_int_select[2] = INT2_GMAC1;
151 	sc->sc_int_select[3] = INT3_GMAC1;
152 	sc->sc_int_select[4] = INT4_GMAC1;
153 
154 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT0_SELECT, INT0_GMAC1);
155 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT1_SELECT, INT1_GMAC1);
156 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT2_SELECT, INT2_GMAC1);
157 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT3_SELECT, INT3_GMAC1);
158 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT4_SELECT, INT4_GMAC1);
159 
160 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT0_STATUS, ~0);
161 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT1_STATUS, ~0);
162 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT2_STATUS, ~0);
163 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT3_STATUS, ~0);
164 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, GMAC_INT4_STATUS, ~0);
165 
166 	gmac_intr_update(sc);
167 
168 	aprint_debug_dev(sc->sc_dev, "gmac_init: sts=%#x/%#x/%#x/%#x/%#x\n",
169 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT0_STATUS),
170 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT1_STATUS),
171 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT2_STATUS),
172 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT3_STATUS),
173 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT4_STATUS));
174 
175 	aprint_debug_dev(sc->sc_dev, "gmac_init: mask=%#x/%#x/%#x/%#x/%#x\n",
176 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT0_MASK),
177 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT1_MASK),
178 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT2_MASK),
179 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT3_MASK),
180 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT4_MASK));
181 
182 	aprint_debug_dev(sc->sc_dev, "gmac_init: select=%#x/%#x/%#x/%#x/%#x\n",
183 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT0_SELECT),
184 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT1_SELECT),
185 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT2_SELECT),
186 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT3_SELECT),
187 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, GMAC_INT4_SELECT));
188 
189 	aprint_debug_dev(sc->sc_dev, "gmac_init: create rx dmamap cache\n");
190 	/*
191 	 * Allocate the cache for receive dmamaps.
192 	 */
193 	sc->sc_rxmaps = gmac_mapcache_create(sc->sc_dmat, MAX_RXMAPS,
194 	    MCLBYTES, 1);
195 	KASSERT(sc->sc_rxmaps != NULL);
196 
197 	aprint_debug_dev(sc->sc_dev, "gmac_init: create tx dmamap cache\n");
198 	/*
199 	 * Allocate the cache for transmit dmamaps.
200 	 */
201 	sc->sc_txmaps = gmac_mapcache_create(sc->sc_dmat, MAX_TXMAPS,
202 	    ETHERMTU_JUMBO + ETHER_HDR_LEN, 16);
203 	KASSERT(sc->sc_txmaps != NULL);
204 
205 	aprint_debug_dev(sc->sc_dev, "gmac_init: create sw freeq\n");
206 	/*
207 	 * Allocate the memory for sw (receive) free queue
208 	 */
209 	hqm = gmac_hwqmem_create(sc->sc_rxmaps, 32 /*SWFREEQ_DESCS*/, 1,
210 	    HQM_PRODUCER|HQM_RX);
211 	sc->sc_swfreeq = gmac_hwqueue_create(hqm, sc->sc_iot, sc->sc_ioh,
212 	    GMAC_SWFREEQ_RWPTR, GMAC_SWFREEQ_BASE, 0);
213 	KASSERT(sc->sc_swfreeq != NULL);
214 
215 	aprint_debug_dev(sc->sc_dev, "gmac_init: create hw freeq\n");
216 	/*
217 	 * Allocate the memory for hw (receive) free queue
218 	 */
219 	hqm = gmac_hwqmem_create(sc->sc_rxmaps, HWFREEQ_DESCS, 1,
220 	    HQM_PRODUCER|HQM_RX);
221 	sc->sc_hwfreeq = gmac_hwqueue_create(hqm, sc->sc_iot, sc->sc_ioh,
222 	    GMAC_HWFREEQ_RWPTR, GMAC_HWFREEQ_BASE, 0);
223 	KASSERT(sc->sc_hwfreeq != NULL);
224 
225 	aprint_debug_dev(sc->sc_dev, "gmac_init: done\n");
226 }
227 
228 int
229 geminigmac_match(device_t parent, cfdata_t cf, void *aux)
230 {
231 	struct obio_attach_args *obio = aux;
232 
233 	if (obio->obio_addr != GEMINI_GMAC_BASE)
234 		return 0;
235 
236 	return 1;
237 }
238 
239 void
240 geminigmac_attach(device_t parent, device_t self, void *aux)
241 {
242 	struct gmac_softc *sc = device_private(self);
243 	struct obio_attach_args *obio = aux;
244 	struct gmac_attach_args gma;
245 	cfdata_t cf;
246 	uint32_t v;
247 	int error;
248 
249 	sc->sc_dev = self;
250 	sc->sc_iot = obio->obio_iot;
251 	sc->sc_dmat = obio->obio_dmat;
252 	sc->sc_gpio_dev = geminigpio_cd.cd_devs[0];
253 	sc->sc_gpio_mdclk = GPIO_MDCLK;
254 	sc->sc_gpio_mdout = GPIO_MDIO;
255 	sc->sc_gpio_mdin = GPIO_MDIO;
256 	KASSERT(sc->sc_gpio_dev != NULL);
257 
258 	error = bus_space_map(sc->sc_iot, obio->obio_addr, obio->obio_size, 0,
259 	    &sc->sc_ioh);
260 	if (error) {
261 		aprint_error(": error mapping registers: %d", error);
262 		return;
263 	}
264 
265 	v = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0);
266 	aprint_normal(": devid %d rev %d\n", GMAC_TOE_DEVID(v),
267 	    GMAC_TOE_REVID(v));
268 	aprint_naive("\n");
269 
270 	mutex_init(&sc->sc_mdiolock, MUTEX_DEFAULT, IPL_NET);
271 
272 	/*
273 	 * Initialize the GPIO pins
274 	 */
275 	geminigpio_pin_ctl(sc->sc_gpio_dev, sc->sc_gpio_mdclk, GPIO_PIN_OUTPUT);
276 	geminigpio_pin_ctl(sc->sc_gpio_dev, sc->sc_gpio_mdout, GPIO_PIN_OUTPUT);
277 	if (sc->sc_gpio_mdout != sc->sc_gpio_mdin)
278 		geminigpio_pin_ctl(sc->sc_gpio_dev, sc->sc_gpio_mdin,
279 		    GPIO_PIN_INPUT);
280 
281 	/*
282 	 * Set the MDIO GPIO pins to a known state.
283 	 */
284 	geminigpio_pin_write(sc->sc_gpio_dev, sc->sc_gpio_mdclk, 0);
285 	geminigpio_pin_write(sc->sc_gpio_dev, sc->sc_gpio_mdout, 0);
286 	sc->sc_mdiobits = MDCLK;
287 
288 	gmac_init(sc);
289 
290 	gma.gma_iot = sc->sc_iot;
291 	gma.gma_ioh = sc->sc_ioh;
292 	gma.gma_dmat = sc->sc_dmat;
293 
294 	gma.gma_mii_readreg = geminigmac_mii_readreg;
295 	gma.gma_mii_writereg = geminigmac_mii_writereg;
296 
297 	gma.gma_port = 0;
298 	gma.gma_phy = -1;
299 	gma.gma_intr = 1;
300 
301 	cf = config_search(sc->sc_dev, &gma,
302 	    CFARG_SUBMATCH, geminigmac_find,
303 	    CFARG_IATTR, geminigmac_cd.cd_name,
304 	    CFARG_EOL);
305 	if (cf != NULL)
306 		config_attach(sc->sc_dev, cf, &gma, geminigmac_print,
307 		    CFARG_EOL);
308 
309 	gma.gma_port = 1;
310 	gma.gma_phy = -1;
311 	gma.gma_intr = 2;
312 
313 	cf = config_search(sc->sc_dev, &gma,
314 	    CFARG_SUBMATCH, geminigmac_find,
315 	    CFARG_IATTR, geminigmac_cd.cd_name,
316 	    CFARG_EOL);
317 	if (cf != NULL)
318 		config_attach(sc->sc_dev, cf, &gma, geminigmac_print,
319 		    CFARG_EOL);
320 }
321 
322 static int
323 geminigmac_find(device_t parent, cfdata_t cf, const int *ldesc, void *aux)
324 {
325 	struct gmac_attach_args * const gma = aux;
326 
327 	if (gma->gma_port != cf->cf_loc[GEMINIGMACCF_PORT])
328 		return 0;
329 	if (gma->gma_intr != cf->cf_loc[GEMINIGMACCF_INTR])
330 		return 0;
331 
332 	gma->gma_phy = cf->cf_loc[GEMINIGMACCF_PHY];
333 	gma->gma_intr = cf->cf_loc[GEMINIGMACCF_INTR];
334 
335 	return config_match(parent, cf, gma);
336 }
337 
338 static int
339 geminigmac_print(void *aux, const char *name)
340 {
341 	struct gmac_attach_args * const gma = aux;
342 
343 	aprint_normal(" port %d", gma->gma_port);
344 	aprint_normal(" phy %d", gma->gma_phy);
345 	aprint_normal(" intr %d", gma->gma_intr);
346 
347 	return UNCONF;
348 }
349 
350 static uint32_t
351 gemini_gmac_gpio_read(device_t dv)
352 {
353 	struct gmac_softc * const sc = device_private(dv);
354 	int value = geminigpio_pin_read(sc->sc_gpio_dev, GPIO_MDIO);
355 
356 	KASSERT((sc->sc_mdiobits & MDTOPHY) == 0);
357 
358 	return value ? MDIN : 0;
359 }
360 
361 static void
362 gemini_gmac_gpio_write(device_t dv, uint32_t bits)
363 {
364 	struct gmac_softc * const sc = device_private(dv);
365 
366 	if ((sc->sc_mdiobits ^ bits) & MDTOPHY) {
367 		int flags = (bits & MDTOPHY) ? GPIO_PIN_OUTPUT : GPIO_PIN_INPUT;
368 		geminigpio_pin_ctl(sc->sc_gpio_dev, GPIO_MDIO, flags);
369 	}
370 
371 	if ((sc->sc_mdiobits ^ bits) & MDOUT) {
372 		int flags = ((bits & MDOUT) != 0);
373 		geminigpio_pin_write(sc->sc_gpio_dev, GPIO_MDIO, flags);
374 	}
375 
376 	if ((sc->sc_mdiobits ^ bits) & MDCLK) {
377 		int flags = ((bits & MDCLK) != 0);
378 		geminigpio_pin_write(sc->sc_gpio_dev, GPIO_MDCLK, flags);
379 	}
380 
381 	sc->sc_mdiobits = bits;
382 }
383 
384 static const struct mii_bitbang_ops geminigmac_mii_bitbang_ops = {
385 	.mbo_read = gemini_gmac_gpio_read,
386 	.mbo_write = gemini_gmac_gpio_write,
387 	.mbo_bits[MII_BIT_MDO] = MDOUT,
388 	.mbo_bits[MII_BIT_MDI] = MDIN,
389 	.mbo_bits[MII_BIT_MDC] = MDCLK,
390 	.mbo_bits[MII_BIT_DIR_HOST_PHY] = MDTOPHY,
391 };
392 
393 int
394 geminigmac_mii_readreg(device_t dv, int phy, int reg, uint16_t *val)
395 {
396 	device_t parent = device_parent(dv);
397 	struct gmac_softc * const sc = device_private(parent);
398 	int rv;
399 
400 	mutex_enter(&sc->sc_mdiolock);
401 	rv = mii_bitbang_readreg(parent, &geminigmac_mii_bitbang_ops, phy,
402 	    reg, val);
403 	mutex_exit(&sc->sc_mdiolock);
404 
405 	//aprint_debug_dev(dv, "mii_readreg(%d, %d): %#x\n", phy, reg, rv);
406 
407 	return rv;
408 }
409 
410 int
411 geminigmac_mii_writereg(device_t dv, int phy, int reg, uint16_t val)
412 {
413 	device_t parent = device_parent(dv);
414 	struct gmac_softc * const sc = device_private(parent);
415 
416 	//aprint_debug_dev(dv, "mii_writereg(%d, %d, %#x)\n", phy, reg, val);
417 
418 	mutex_enter(&sc->sc_mdiolock);
419 	rv = mii_bitbang_writereg(parent, &geminigmac_mii_bitbang_ops, phy,
420 	    reg, val);
421 	mutex_exit(&sc->sc_mdiolock);
422 
423 	return rv;
424 }
425 
426 
427 gmac_mapcache_t *
428 gmac_mapcache_create(bus_dma_tag_t dmat, size_t maxmaps, bus_size_t mapsize,
429     int nsegs)
430 {
431 	gmac_mapcache_t *mc;
432 
433 	mc = kmem_zalloc(offsetof(gmac_mapcache_t, mc_maps[maxmaps]),
434 	    KM_SLEEP);
435 	if (mc == NULL)
436 		return NULL;
437 
438 	mc->mc_max = maxmaps;
439 	mc->mc_dmat = dmat;
440 	mc->mc_mapsize = mapsize;
441 	mc->mc_nsegs = nsegs;
442 	return mc;
443 }
444 
445 void
446 gmac_mapcache_destroy(gmac_mapcache_t **mc_p)
447 {
448 	gmac_mapcache_t *mc = *mc_p;
449 
450 	if (mc == NULL)
451 		return;
452 
453 	KASSERT(mc->mc_used == 0);
454 	while (mc->mc_free-- > 0) {
455 		KASSERT(mc->mc_maps[mc->mc_free] != NULL);
456 		bus_dmamap_destroy(mc->mc_dmat, mc->mc_maps[mc->mc_free]);
457 		mc->mc_maps[mc->mc_free] = NULL;
458 	}
459 
460 	kmem_free(mc, offsetof(gmac_mapcache_t, mc_maps[mc->mc_max]));
461 	*mc_p = NULL;
462 }
463 
464 int
465 gmac_mapcache_fill(gmac_mapcache_t *mc, size_t limit)
466 {
467 	int error;
468 
469 	KASSERT(limit <= mc->mc_max);
470 	aprint_debug("gmac_mapcache_fill(%p): limit=%zu used=%zu free=%zu\n",
471 	    mc, limit, mc->mc_used, mc->mc_free);
472 
473 	for (error = 0; mc->mc_free + mc->mc_used < limit; mc->mc_free++) {
474 		KASSERT(mc->mc_maps[mc->mc_free] == NULL);
475 		error = bus_dmamap_create(mc->mc_dmat, mc->mc_mapsize,
476 		    mc->mc_nsegs, mc->mc_mapsize, 0,
477 		    BUS_DMA_ALLOCNOW|BUS_DMA_WAITOK,
478 		    &mc->mc_maps[mc->mc_free]);
479 		if (error)
480 			break;
481 	}
482 	aprint_debug("gmac_mapcache_fill(%p): limit=%zu used=%zu free=%zu\n",
483 	    mc, limit, mc->mc_used, mc->mc_free);
484 
485 	return error;
486 }
487 
488 bus_dmamap_t
489 gmac_mapcache_get(gmac_mapcache_t *mc)
490 {
491 	bus_dmamap_t map;
492 
493 	KASSERT(mc != NULL);
494 
495 	if (mc->mc_free == 0) {
496 		int error;
497 		if (mc->mc_used == mc->mc_max)
498 			return NULL;
499 		error = bus_dmamap_create(mc->mc_dmat, mc->mc_mapsize,
500 		    mc->mc_nsegs, mc->mc_mapsize, 0,
501 		    BUS_DMA_ALLOCNOW|BUS_DMA_NOWAIT,
502 		    &map);
503 		if (error)
504 			return NULL;
505 		KASSERT(mc->mc_maps[mc->mc_free] == NULL);
506 	} else {
507 		KASSERT(mc->mc_free <= mc->mc_max);
508 		map = mc->mc_maps[--mc->mc_free];
509 		mc->mc_maps[mc->mc_free] = NULL;
510 	}
511 	mc->mc_used++;
512 	KASSERT(map != NULL);
513 
514 	return map;
515 }
516 
517 void
518 gmac_mapcache_put(gmac_mapcache_t *mc, bus_dmamap_t map)
519 {
520 	KASSERT(mc->mc_free + mc->mc_used < mc->mc_max);
521 	KASSERT(mc->mc_maps[mc->mc_free] == NULL);
522 
523 	mc->mc_maps[mc->mc_free++] = map;
524 	mc->mc_used--;
525 }
526 
527 gmac_desc_t *
528 gmac_hwqueue_desc(gmac_hwqueue_t *hwq, size_t i)
529 {
530 	i += hwq->hwq_wptr;
531 	if (i >= hwq->hwq_size)
532 		i -= hwq->hwq_size;
533 	return hwq->hwq_base + i;
534 }
535 
536 static void
537 gmac_hwqueue_txconsume(gmac_hwqueue_t *hwq, const gmac_desc_t *d)
538 {
539 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
540 	struct ifnet *ifp;
541 	bus_dmamap_t map;
542 	struct mbuf *m;
543 
544 	IF_DEQUEUE(&hwq->hwq_ifq, m);
545 	KASSERT(m != NULL);
546 	map = M_GETCTX(m, bus_dmamap_t);
547 
548 	bus_dmamap_sync(hqm->hqm_dmat, map, 0, map->dm_mapsize,
549 	    BUS_DMASYNC_POSTWRITE);
550 	bus_dmamap_unload(hqm->hqm_dmat, map);
551 	M_SETCTX(m, NULL);
552 	gmac_mapcache_put(hqm->hqm_mc, map);
553 
554 	ifp = hwq->hwq_ifp;
555 	if_statinc(ifp, if_opackets);
556 	if_statiadd(ifp, if_obytes,	 m->m_pkthdr.len);
557 
558 	aprint_debug("gmac_hwqueue_txconsume(%p): %zu@%p: %s m=%p\n",
559 	    hwq, d - hwq->hwq_base, d, ifp->if_xname, m);
560 
561 	bpf_mtap(ifp, m, BPF_D_OUT);
562 	m_freem(m);
563 }
564 
565 void
566 gmac_hwqueue_sync(gmac_hwqueue_t *hwq)
567 {
568 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
569 	uint32_t v;
570 	uint16_t old_rptr;
571 	size_t rptr;
572 
573 	KASSERT(hqm->hqm_flags & HQM_PRODUCER);
574 
575 	old_rptr = hwq->hwq_rptr;
576 	v = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
577 	hwq->hwq_rptr = (v >>  0) & 0xffff;
578 	hwq->hwq_wptr = (v >> 16) & 0xffff;
579 
580 	if (old_rptr == hwq->hwq_rptr)
581 		return;
582 
583 	aprint_debug("gmac_hwqueue_sync(%p): entry rptr old=%u new=%u free=%u(%u)\n",
584 	    hwq, old_rptr, hwq->hwq_rptr, hwq->hwq_free,
585 	    hwq->hwq_size - hwq->hwq_free - 1);
586 
587 	hwq->hwq_free += (hwq->hwq_rptr - old_rptr) & (hwq->hwq_size - 1);
588 	for (rptr = old_rptr;
589 	     rptr != hwq->hwq_rptr;
590 	     rptr = (rptr + 1) & (hwq->hwq_size - 1)) {
591 		gmac_desc_t * const d = hwq->hwq_base + rptr;
592 		if (hqm->hqm_flags & HQM_TX) {
593 			bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
594 			    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
595 			    sizeof(gmac_desc_t),
596 			    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
597 			if (d->d_desc3 & htole32(DESC3_EOF))
598 				gmac_hwqueue_txconsume(hwq, d);
599 		} else {
600 			bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
601 			    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
602 			    sizeof(gmac_desc_t),
603 			    BUS_DMASYNC_POSTWRITE);
604 
605 			aprint_debug("gmac_hwqueue_sync(%p): %zu@%p=%#x/%#x/%#x/%#x\n",
606 			    hwq, rptr, d, d->d_desc0, d->d_desc1,
607 			    d->d_bufaddr, d->d_desc3);
608 			bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
609 			    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
610 			    sizeof(gmac_desc_t),
611 			    BUS_DMASYNC_PREWRITE);
612 		}
613 	}
614 
615 	aprint_debug("gmac_hwqueue_sync(%p): exit rptr old=%u new=%u free=%u(%u)\n",
616 	    hwq, old_rptr, hwq->hwq_rptr, hwq->hwq_free,
617 	    hwq->hwq_size - hwq->hwq_free - 1);
618 }
619 
620 void
621 gmac_hwqueue_produce(gmac_hwqueue_t *hwq, size_t count)
622 {
623 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
624 	uint16_t wptr;
625 	uint16_t rptr = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
626 
627 	KASSERT(count < hwq->hwq_free);
628 	KASSERT(hqm->hqm_flags & HQM_PRODUCER);
629 	KASSERT(hwq->hwq_wptr == bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0) >> 16);
630 
631 	aprint_debug("gmac_hwqueue_produce(%p, %zu): rptr=%u(%u) wptr old=%u",
632 	    hwq, count, hwq->hwq_rptr, rptr, hwq->hwq_wptr);
633 
634 	hwq->hwq_free -= count;
635 #if 1
636 	for (wptr = hwq->hwq_wptr;
637 	     count > 0;
638 	     count--, wptr = (wptr + 1) & (hwq->hwq_size - 1)) {
639 		KASSERT(((wptr + 1) & (hwq->hwq_size - 1)) != hwq->hwq_rptr);
640 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
641 		    sizeof(gmac_desc_t [hwq->hwq_qoff + wptr]),
642 		    sizeof(gmac_desc_t),
643 		    BUS_DMASYNC_PREWRITE);
644 	}
645 	KASSERT(count == 0);
646 	hwq->hwq_wptr = wptr;
647 #else
648 	if (hwq->hwq_wptr + count >= hwq->hwq_size) {
649 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
650 		    sizeof(gmac_desc_t [hwq->hwq_qoff + hwq->hwq_wptr]),
651 		    sizeof(gmac_desc_t [hwq->hwq_size - hwq->hwq_wptr]),
652 		    BUS_DMASYNC_PREWRITE);
653 		count -= hwq->hwq_size - hwq->hwq_wptr;
654 		hwq->hwq_wptr = 0;
655 	}
656 	if (count > 0) {
657 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
658 		    sizeof(gmac_desc_t [hwq->hwq_qoff + hwq->hwq_wptr]),
659 		    sizeof(gmac_desc_t [count]),
660 		    BUS_DMASYNC_PREWRITE);
661 		hwq->hwq_wptr += count;
662 		hwq->hwq_wptr &= (hwq->hwq_size - 1);
663 	}
664 #endif
665 
666 	/*
667 	 * Tell the h/w we've produced a few more descriptors.
668 	 * (don't bother writing the rptr since it's RO).
669 	 */
670 	bus_space_write_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0,
671 	    hwq->hwq_wptr << 16);
672 
673 	aprint_debug(" new=%u\n", hwq->hwq_wptr);
674 }
675 
676 size_t
677 gmac_rxproduce(gmac_hwqueue_t *hwq, size_t free_min)
678 {
679 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
680 	size_t i;
681 
682 	aprint_debug("gmac_rxproduce(%p): entry free=%u(%u) free_min=%zu ifq_len=%d\n",
683 	    hwq, hwq->hwq_free, hwq->hwq_size - hwq->hwq_free - 1,
684 	    free_min, hwq->hwq_ifq.ifq_len);
685 
686 	gmac_hwqueue_sync(hwq);
687 
688 	aprint_debug("gmac_rxproduce(%p): postsync free=%u(%u)\n",
689 	    hwq, hwq->hwq_free, hwq->hwq_size - hwq->hwq_free - 1);
690 
691 	for (i = 0; hwq->hwq_free > 0 && hwq->hwq_size - hwq->hwq_free - 1 < free_min; i++) {
692 		bus_dmamap_t map;
693 		gmac_desc_t * const d = gmac_hwqueue_desc(hwq, 0);
694 		struct mbuf *m, *m0;
695 		int error;
696 
697 		if (d->d_bufaddr && (le32toh(d->d_bufaddr) >> 16) != 0xdead) {
698 			gmac_hwqueue_produce(hwq, 1);
699 			continue;
700 		}
701 
702 		map = gmac_mapcache_get(hqm->hqm_mc);
703 		if (map == NULL)
704 			break;
705 
706 		KASSERT(map->dm_mapsize == 0);
707 
708 		m = m_gethdr(M_DONTWAIT, MT_DATA);
709 		if (m == NULL) {
710 			gmac_mapcache_put(hqm->hqm_mc, map);
711 			break;
712 		}
713 
714 		MCLGET(m, M_DONTWAIT);
715 		if ((m->m_flags & M_EXT) == 0) {
716 			m_free(m);
717 			gmac_mapcache_put(hqm->hqm_mc, map);
718 			break;
719 		}
720 		error = bus_dmamap_load(hqm->hqm_dmat, map, m->m_data,
721 		    MCLBYTES, NULL, BUS_DMA_READ|BUS_DMA_NOWAIT);
722 		if (error) {
723 			m_free(m);
724 			gmac_mapcache_put(hqm->hqm_mc, map);
725 			aprint_error("gmac0: "
726 			    "map %p(%zu): can't map rx mbuf(%p) wptr=%u: %d\n",
727 			    map, map->_dm_size, m, hwq->hwq_wptr, error);
728 			Debugger();
729 			break;
730 		}
731 		bus_dmamap_sync(hqm->hqm_dmat, map, 0, map->dm_mapsize,
732 		    BUS_DMASYNC_PREREAD);
733 		m->m_pkthdr.len = 0;
734 		M_SETCTX(m, map);
735 #if 0
736 		d->d_desc0   = htole32(map->dm_segs->ds_len);
737 #endif
738 		d->d_bufaddr = htole32(map->dm_segs->ds_addr);
739 		for (m0 = hwq->hwq_ifq.ifq_head; m0 != NULL; m0 = m0->m_nextpkt)
740 			KASSERT(m0 != m);
741 		m->m_len = d - hwq->hwq_base;
742 		IF_ENQUEUE(&hwq->hwq_ifq, m);
743 		aprint_debug(
744 		    "gmac_rxproduce(%p): m=%p %zu@%p=%#x/%#x/%#x/%#x\n", hwq,
745 		    m, d - hwq->hwq_base, d, d->d_desc0, d->d_desc1,
746 		    d->d_bufaddr, d->d_desc3);
747 		gmac_hwqueue_produce(hwq, 1);
748 	}
749 
750 	aprint_debug("gmac_rxproduce(%p): exit free=%u(%u) free_min=%zu ifq_len=%d\n",
751 	    hwq, hwq->hwq_free, hwq->hwq_size - hwq->hwq_free - 1,
752 	    free_min, hwq->hwq_ifq.ifq_len);
753 
754 	return i;
755 }
756 
757 static bool
758 gmac_hwqueue_rxconsume(gmac_hwqueue_t *hwq, const gmac_desc_t *d)
759 {
760 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
761 	struct ifnet * const ifp = hwq->hwq_ifp;
762 	size_t buflen = d->d_desc1 & 0xffff;
763 	bus_dmamap_t map;
764 	struct mbuf *m, *last_m, **mp;
765 	size_t depth;
766 
767 	KASSERT(ifp != NULL);
768 
769 	aprint_debug("gmac_hwqueue_rxconsume(%p): entry\n", hwq);
770 
771 	aprint_debug("gmac_hwqueue_rxconsume(%p): ifp=%p(%s): %#x/%#x/%#x/%#x\n",
772 	    hwq, hwq->hwq_ifp, hwq->hwq_ifp->if_xname,
773 	    d->d_desc0, d->d_desc1, d->d_bufaddr, d->d_desc3);
774 
775 	if (d->d_bufaddr == 0 || d->d_bufaddr == 0xdeadbeef)
776 		return false;
777 
778 	/*
779 	 * First we have to find this mbuf in the software free queue
780 	 * (the producer of the mbufs) and remove it.
781 	 */
782 	KASSERT(hwq->hwq_producer->hwq_free != hwq->hwq_producer->hwq_size - 1);
783 	for (mp = &hwq->hwq_producer->hwq_ifq.ifq_head, last_m = NULL, depth=0;
784 	     (m = *mp) != NULL;
785 	     last_m = m, mp = &m->m_nextpkt, depth++) {
786 		map = M_GETCTX(m, bus_dmamap_t);
787 		KASSERT(map != NULL);
788 		KASSERT(map->dm_nsegs == 1);
789 		aprint_debug("gmac_hwqueue_rxconsume(%p): ifq[%zu]=%p(@%#zx) %d@swfq\n",
790 		    hwq, depth, m, map->dm_segs->ds_addr, m->m_len);
791 		if (le32toh(d->d_bufaddr) == map->dm_segs->ds_addr) {
792 			*mp = m->m_nextpkt;
793 			if (hwq->hwq_producer->hwq_ifq.ifq_tail == m)
794 				hwq->hwq_producer->hwq_ifq.ifq_tail = last_m;
795 			hwq->hwq_producer->hwq_ifq.ifq_len--;
796 			break;
797 		}
798 	}
799 	aprint_debug("gmac_hwqueue_rxconsume(%p): ifp=%p(%s) m=%p@%zu",
800 	    hwq, hwq->hwq_ifp, hwq->hwq_ifp->if_xname, m, depth);
801 	if (m)
802 		aprint_debug(" swfq[%d]=%#x\n", m->m_len,
803 		    hwq->hwq_producer->hwq_base[m->m_len].d_bufaddr);
804 	aprint_debug("\n");
805 	KASSERT(m != NULL);
806 
807 	{
808 		struct mbuf *m0;
809 		for (m0 = hwq->hwq_producer->hwq_ifq.ifq_head; m0 != NULL; m0 = m0->m_nextpkt)
810 			KASSERT(m0 != m);
811 	}
812 
813 	KASSERT(hwq->hwq_producer->hwq_base[m->m_len].d_bufaddr == d->d_bufaddr);
814 	hwq->hwq_producer->hwq_base[m->m_len].d_bufaddr = htole32(0xdead0000 | m->m_len);
815 
816 	m->m_len = buflen;
817 	if (d->d_desc3 & DESC3_SOF) {
818 		KASSERT(hwq->hwq_rxmbuf == NULL);
819 		m->m_pkthdr.len = buflen;
820 		buflen += 2;	/* account for the pad */
821 		/* only modify m->m_data after we know mbuf is good. */
822 	} else {
823 		KASSERT(hwq->hwq_rxmbuf != NULL);
824 		hwq->hwq_rxmbuf->m_pkthdr.len += buflen;
825 	}
826 
827 	map = M_GETCTX(m, bus_dmamap_t);
828 
829 	/*
830 	 * Sync the buffer contents, unload the dmamap, and save it away.
831 	 */
832 	bus_dmamap_sync(hqm->hqm_dmat, map, 0, buflen, BUS_DMASYNC_POSTREAD);
833 	bus_dmamap_unload(hqm->hqm_dmat, map);
834 	M_SETCTX(m, NULL);
835 	gmac_mapcache_put(hqm->hqm_mc, map);
836 
837 	/*
838 	 * Now we build our new packet chain by tacking this on the end.
839 	 */
840 	*hwq->hwq_mp = m;
841 	if ((d->d_desc3 & DESC3_EOF) == 0) {
842 		/*
843 		 * Not last frame, so make sure the next gets appended right.
844 		 */
845 		hwq->hwq_mp = &m->m_next;
846 		return true;
847 	}
848 
849 #if 0
850 	/*
851 	 * We have a complete frame, let's try to deliver it.
852 	 */
853 	m->m_len -= ETHER_CRC_LEN;	/* remove the CRC from the end */
854 #endif
855 
856 	/*
857 	 * Now get the whole chain.
858 	 */
859 	m = hwq->hwq_rxmbuf;
860 	m_set_rcvif(m, ifp);	/* set receive interface */
861 	switch (DESC0_RXSTS_GET(d->d_desc0)) {
862 	case DESC0_RXSTS_GOOD:
863 	case DESC0_RXSTS_LONG:
864 		m->m_data += 2;
865 		if_percpuq_enqueue(ifp->if_percpuq, m);
866 		break;
867 	default:
868 		if_statinc(ifp, if_ierrors);
869 		m_freem(m);
870 		break;
871 	}
872 	hwq->hwq_rxmbuf = NULL;
873 	hwq->hwq_mp = &hwq->hwq_rxmbuf;
874 
875 	return true;
876 }
877 
878 size_t
879 gmac_hwqueue_consume(gmac_hwqueue_t *hwq, size_t free_min)
880 {
881 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
882 	gmac_desc_t d;
883 	uint32_t v;
884 	uint16_t rptr;
885 	size_t i;
886 
887 	KASSERT((hqm->hqm_flags & HQM_PRODUCER) == 0);
888 
889 	aprint_debug("gmac_hwqueue_consume(%p): entry\n", hwq);
890 
891 
892 	v = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
893 	rptr = (v >>  0) & 0xffff;
894 	hwq->hwq_wptr = (v >> 16) & 0xffff;
895 	KASSERT(rptr == hwq->hwq_rptr);
896 	if (rptr == hwq->hwq_wptr)
897 		return 0;
898 
899 	i = 0;
900 	for (; rptr != hwq->hwq_wptr; rptr = (rptr + 1) & (hwq->hwq_size - 1)) {
901 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
902 		    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
903 		    sizeof(gmac_desc_t),
904 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
905 		d.d_desc0   = le32toh(hwq->hwq_base[rptr].d_desc0);
906 		d.d_desc1   = le32toh(hwq->hwq_base[rptr].d_desc1);
907 		d.d_bufaddr = le32toh(hwq->hwq_base[rptr].d_bufaddr);
908 		d.d_desc3   = le32toh(hwq->hwq_base[rptr].d_desc3);
909 		hwq->hwq_base[rptr].d_desc0 = 0;
910 		hwq->hwq_base[rptr].d_desc1 = 0;
911 		hwq->hwq_base[rptr].d_bufaddr = 0xdeadbeef;
912 		hwq->hwq_base[rptr].d_desc3 = 0;
913 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
914 		    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
915 		    sizeof(gmac_desc_t),
916 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
917 
918 		aprint_debug("gmac_hwqueue_consume(%p): rptr=%u\n",
919 		    hwq, rptr);
920 		if (!gmac_hwqueue_rxconsume(hwq, &d)) {
921 			rptr = (rptr + 1) & (hwq->hwq_size - 1);
922 			i += gmac_rxproduce(hwq->hwq_producer, free_min);
923 			break;
924 		}
925 	}
926 
927 	/*
928 	 * Update hardware's copy of rptr.  (wptr is RO).
929 	 */
930 	aprint_debug("gmac_hwqueue_consume(%p): rptr old=%u new=%u wptr=%u\n",
931 	    hwq, hwq->hwq_rptr, rptr, hwq->hwq_wptr);
932 	bus_space_write_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0, rptr);
933 	hwq->hwq_rptr = rptr;
934 
935 	aprint_debug("gmac_hwqueue_consume(%p): exit\n", hwq);
936 
937 	return i;
938 }
939 
940 void
941 gmac_hwqmem_destroy(gmac_hwqmem_t *hqm)
942 {
943 	if (hqm->hqm_nsegs) {
944 		if (hqm->hqm_base) {
945 			if (hqm->hqm_dmamap) {
946 				if (hqm->hqm_dmamap->dm_mapsize) {
947 					bus_dmamap_unload(hqm->hqm_dmat,
948 					    hqm->hqm_dmamap);
949 				}
950 				bus_dmamap_destroy(hqm->hqm_dmat,
951 				     hqm->hqm_dmamap);
952 			}
953 			bus_dmamem_unmap(hqm->hqm_dmat, hqm->hqm_base,
954 			    hqm->hqm_memsize);
955 		}
956 		bus_dmamem_free(hqm->hqm_dmat, hqm->hqm_segs, hqm->hqm_nsegs);
957 	}
958 
959 	kmem_free(hqm, sizeof(*hqm));
960 }
961 
962 gmac_hwqmem_t *
963 gmac_hwqmem_create(gmac_mapcache_t *mc, size_t ndesc, size_t nqueue, int flags)
964 {
965 	gmac_hwqmem_t *hqm;
966 	int error;
967 
968 	KASSERT(ndesc > 0 && ndesc <= 2048);
969 	KASSERT((ndesc & (ndesc - 1)) == 0);
970 
971 	hqm = kmem_zalloc(sizeof(*hqm), KM_SLEEP);
972 	hqm->hqm_memsize = nqueue * sizeof(gmac_desc_t [ndesc]);
973 	hqm->hqm_mc = mc;
974 	hqm->hqm_dmat = mc->mc_dmat;
975 	hqm->hqm_ndesc = ndesc;
976 	hqm->hqm_nqueue = nqueue;
977 	hqm->hqm_flags = flags;
978 
979 	error = bus_dmamem_alloc(hqm->hqm_dmat, hqm->hqm_memsize, 0, 0,
980 	    hqm->hqm_segs, 1, &hqm->hqm_nsegs, BUS_DMA_WAITOK);
981 	if (error) {
982 		KASSERT(error == 0);
983 		goto failed;
984 	}
985 	KASSERT(hqm->hqm_nsegs == 1);
986 	error = bus_dmamem_map(hqm->hqm_dmat, hqm->hqm_segs, hqm->hqm_nsegs,
987 	    hqm->hqm_memsize, (void **)&hqm->hqm_base, BUS_DMA_WAITOK);
988 	if (error) {
989 		KASSERT(error == 0);
990 		goto failed;
991 	}
992 	error = bus_dmamap_create(hqm->hqm_dmat, hqm->hqm_memsize,
993 	    hqm->hqm_nsegs, hqm->hqm_memsize, 0,
994 	    BUS_DMA_WAITOK|BUS_DMA_ALLOCNOW, &hqm->hqm_dmamap);
995 	if (error) {
996 		KASSERT(error == 0);
997 		goto failed;
998 	}
999 	error = bus_dmamap_load(hqm->hqm_dmat, hqm->hqm_dmamap, hqm->hqm_base,
1000 	    hqm->hqm_memsize, NULL,
1001 	    BUS_DMA_WAITOK|BUS_DMA_WRITE|BUS_DMA_READ|BUS_DMA_COHERENT);
1002 	if (error) {
1003 		aprint_debug("gmac_hwqmem_create: ds_addr=%zu ds_len=%zu\n",
1004 		    hqm->hqm_segs->ds_addr, hqm->hqm_segs->ds_len);
1005 		aprint_debug("gmac_hwqmem_create: bus_dmamap_load: %d\n", error);
1006 		KASSERT(error == 0);
1007 		goto failed;
1008 	}
1009 
1010 	memset(hqm->hqm_base, 0, hqm->hqm_memsize);
1011 	if ((flags & HQM_PRODUCER) == 0)
1012 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap, 0,
1013 		    hqm->hqm_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1014 
1015 	return hqm;
1016 
1017 failed:
1018 	gmac_hwqmem_destroy(hqm);
1019 	return NULL;
1020 }
1021 
1022 void
1023 gmac_hwqueue_destroy(gmac_hwqueue_t *hwq)
1024 {
1025 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
1026 	KASSERT(hqm->hqm_refs & hwq->hwq_ref);
1027 	hqm->hqm_refs &= ~hwq->hwq_ref;
1028 	for (;;) {
1029 		struct mbuf *m;
1030 		bus_dmamap_t map;
1031 		IF_DEQUEUE(&hwq->hwq_ifq, m);
1032 		if (m == NULL)
1033 			break;
1034 		map = M_GETCTX(m, bus_dmamap_t);
1035 		bus_dmamap_unload(hqm->hqm_dmat, map);
1036 		gmac_mapcache_put(hqm->hqm_mc, map);
1037 		m_freem(m);
1038 	}
1039 	kmem_free(hwq, sizeof(*hwq));
1040 }
1041 
1042 gmac_hwqueue_t *
1043 gmac_hwqueue_create(gmac_hwqmem_t *hqm,
1044     bus_space_tag_t iot, bus_space_handle_t ioh,
1045     bus_size_t qrwptr, bus_size_t qbase,
1046     size_t qno)
1047 {
1048 	const size_t log2_memsize = ffs(hqm->hqm_ndesc) - 1;
1049 	gmac_hwqueue_t *hwq;
1050 	uint32_t v;
1051 
1052 	KASSERT(qno < hqm->hqm_nqueue);
1053 	KASSERT((hqm->hqm_refs & (1 << qno)) == 0);
1054 
1055 	hwq = kmem_zalloc(sizeof(*hwq), KM_SLEEP);
1056 	hwq->hwq_size = hqm->hqm_ndesc;
1057 	hwq->hwq_iot = iot;
1058 	bus_space_subregion(iot, ioh, qrwptr, sizeof(uint32_t),
1059 	    &hwq->hwq_qrwptr_ioh);
1060 
1061 	hwq->hwq_hqm = hqm;
1062 	hwq->hwq_ref = 1 << qno;
1063 	hqm->hqm_refs |= hwq->hwq_ref;
1064 	hwq->hwq_qoff = hqm->hqm_ndesc * qno;
1065 	hwq->hwq_base = hqm->hqm_base + hwq->hwq_qoff;
1066 
1067 	if (qno == 0) {
1068 		bus_space_write_4(hwq->hwq_iot, ioh, qbase,
1069 		     hqm->hqm_dmamap->dm_segs[0].ds_addr | (log2_memsize));
1070 	}
1071 
1072 	v = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
1073 	hwq->hwq_rptr = (v >>  0) & 0xffff;
1074 	hwq->hwq_wptr = (v >> 16) & 0xffff;
1075 
1076 	aprint_debug("gmac_hwqueue_create: %p: qrwptr=%zu(%#zx) wptr=%u rptr=%u"
1077 	    " base=%p@%#zx(%#x) qno=%zu\n",
1078 	    hwq, qrwptr, hwq->hwq_qrwptr_ioh, hwq->hwq_wptr, hwq->hwq_rptr,
1079 	    hwq->hwq_base,
1080 	    hqm->hqm_segs->ds_addr + sizeof(gmac_desc_t [hwq->hwq_qoff]),
1081 	    bus_space_read_4(hwq->hwq_iot, ioh, qbase), qno);
1082 
1083 	hwq->hwq_free = hwq->hwq_size - 1;
1084 	hwq->hwq_ifq.ifq_maxlen = hwq->hwq_free;
1085 	hwq->hwq_mp = &hwq->hwq_rxmbuf;
1086 
1087 	return hwq;
1088 }
1089