xref: /netbsd-src/sys/arch/arm/gemini/gemini_gmac.c (revision 9fb66d812c00ebfb445c0b47dea128f32aa6fe96)
1 /* $NetBSD: gemini_gmac.c,v 1.20 2020/02/04 07:40:45 skrll 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 1.20 2020/02/04 07:40:45 skrll 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_ia(geminigmac_find, sc->sc_dev,
302 	    geminigmac_cd.cd_name, &gma);
303 	if (cf != NULL)
304 		config_attach(sc->sc_dev, cf, &gma, geminigmac_print);
305 
306 	gma.gma_port = 1;
307 	gma.gma_phy = -1;
308 	gma.gma_intr = 2;
309 
310 	cf = config_search_ia(geminigmac_find, sc->sc_dev,
311 	    geminigmac_cd.cd_name, &gma);
312 	if (cf != NULL)
313 		config_attach(sc->sc_dev, cf, &gma, geminigmac_print);
314 }
315 
316 static int
317 geminigmac_find(device_t parent, cfdata_t cf, const int *ldesc, void *aux)
318 {
319 	struct gmac_attach_args * const gma = aux;
320 
321 	if (gma->gma_port != cf->cf_loc[GEMINIGMACCF_PORT])
322 		return 0;
323 	if (gma->gma_intr != cf->cf_loc[GEMINIGMACCF_INTR])
324 		return 0;
325 
326 	gma->gma_phy = cf->cf_loc[GEMINIGMACCF_PHY];
327 	gma->gma_intr = cf->cf_loc[GEMINIGMACCF_INTR];
328 
329 	return config_match(parent, cf, gma);
330 }
331 
332 static int
333 geminigmac_print(void *aux, const char *name)
334 {
335 	struct gmac_attach_args * const gma = aux;
336 
337 	aprint_normal(" port %d", gma->gma_port);
338 	aprint_normal(" phy %d", gma->gma_phy);
339 	aprint_normal(" intr %d", gma->gma_intr);
340 
341 	return UNCONF;
342 }
343 
344 static uint32_t
345 gemini_gmac_gpio_read(device_t dv)
346 {
347 	struct gmac_softc * const sc = device_private(dv);
348 	int value = geminigpio_pin_read(sc->sc_gpio_dev, GPIO_MDIO);
349 
350 	KASSERT((sc->sc_mdiobits & MDTOPHY) == 0);
351 
352 	return value ? MDIN : 0;
353 }
354 
355 static void
356 gemini_gmac_gpio_write(device_t dv, uint32_t bits)
357 {
358 	struct gmac_softc * const sc = device_private(dv);
359 
360 	if ((sc->sc_mdiobits ^ bits) & MDTOPHY) {
361 		int flags = (bits & MDTOPHY) ? GPIO_PIN_OUTPUT : GPIO_PIN_INPUT;
362 		geminigpio_pin_ctl(sc->sc_gpio_dev, GPIO_MDIO, flags);
363 	}
364 
365 	if ((sc->sc_mdiobits ^ bits) & MDOUT) {
366 		int flags = ((bits & MDOUT) != 0);
367 		geminigpio_pin_write(sc->sc_gpio_dev, GPIO_MDIO, flags);
368 	}
369 
370 	if ((sc->sc_mdiobits ^ bits) & MDCLK) {
371 		int flags = ((bits & MDCLK) != 0);
372 		geminigpio_pin_write(sc->sc_gpio_dev, GPIO_MDCLK, flags);
373 	}
374 
375 	sc->sc_mdiobits = bits;
376 }
377 
378 static const struct mii_bitbang_ops geminigmac_mii_bitbang_ops = {
379 	.mbo_read = gemini_gmac_gpio_read,
380 	.mbo_write = gemini_gmac_gpio_write,
381 	.mbo_bits[MII_BIT_MDO] = MDOUT,
382 	.mbo_bits[MII_BIT_MDI] = MDIN,
383 	.mbo_bits[MII_BIT_MDC] = MDCLK,
384 	.mbo_bits[MII_BIT_DIR_HOST_PHY] = MDTOPHY,
385 };
386 
387 int
388 geminigmac_mii_readreg(device_t dv, int phy, int reg, uint16_t *val)
389 {
390 	device_t parent = device_parent(dv);
391 	struct gmac_softc * const sc = device_private(parent);
392 	int rv;
393 
394 	mutex_enter(&sc->sc_mdiolock);
395 	rv = mii_bitbang_readreg(parent, &geminigmac_mii_bitbang_ops, phy,
396 	    reg, val);
397 	mutex_exit(&sc->sc_mdiolock);
398 
399 	//aprint_debug_dev(dv, "mii_readreg(%d, %d): %#x\n", phy, reg, rv);
400 
401 	return rv;
402 }
403 
404 int
405 geminigmac_mii_writereg(device_t dv, int phy, int reg, uint16_t val)
406 {
407 	device_t parent = device_parent(dv);
408 	struct gmac_softc * const sc = device_private(parent);
409 
410 	//aprint_debug_dev(dv, "mii_writereg(%d, %d, %#x)\n", phy, reg, val);
411 
412 	mutex_enter(&sc->sc_mdiolock);
413 	rv = mii_bitbang_writereg(parent, &geminigmac_mii_bitbang_ops, phy,
414 	    reg, val);
415 	mutex_exit(&sc->sc_mdiolock);
416 
417 	return rv;
418 }
419 
420 
421 gmac_mapcache_t *
422 gmac_mapcache_create(bus_dma_tag_t dmat, size_t maxmaps, bus_size_t mapsize,
423     int nsegs)
424 {
425 	gmac_mapcache_t *mc;
426 
427 	mc = kmem_zalloc(offsetof(gmac_mapcache_t, mc_maps[maxmaps]),
428 	    KM_SLEEP);
429 	if (mc == NULL)
430 		return NULL;
431 
432 	mc->mc_max = maxmaps;
433 	mc->mc_dmat = dmat;
434 	mc->mc_mapsize = mapsize;
435 	mc->mc_nsegs = nsegs;
436 	return mc;
437 }
438 
439 void
440 gmac_mapcache_destroy(gmac_mapcache_t **mc_p)
441 {
442 	gmac_mapcache_t *mc = *mc_p;
443 
444 	if (mc == NULL)
445 		return;
446 
447 	KASSERT(mc->mc_used == 0);
448 	while (mc->mc_free-- > 0) {
449 		KASSERT(mc->mc_maps[mc->mc_free] != NULL);
450 		bus_dmamap_destroy(mc->mc_dmat, mc->mc_maps[mc->mc_free]);
451 		mc->mc_maps[mc->mc_free] = NULL;
452 	}
453 
454 	kmem_free(mc, offsetof(gmac_mapcache_t, mc_maps[mc->mc_max]));
455 	*mc_p = NULL;
456 }
457 
458 int
459 gmac_mapcache_fill(gmac_mapcache_t *mc, size_t limit)
460 {
461 	int error;
462 
463 	KASSERT(limit <= mc->mc_max);
464 	aprint_debug("gmac_mapcache_fill(%p): limit=%zu used=%zu free=%zu\n",
465 	    mc, limit, mc->mc_used, mc->mc_free);
466 
467 	for (error = 0; mc->mc_free + mc->mc_used < limit; mc->mc_free++) {
468 		KASSERT(mc->mc_maps[mc->mc_free] == NULL);
469 		error = bus_dmamap_create(mc->mc_dmat, mc->mc_mapsize,
470 		    mc->mc_nsegs, mc->mc_mapsize, 0,
471 		    BUS_DMA_ALLOCNOW|BUS_DMA_WAITOK,
472 		    &mc->mc_maps[mc->mc_free]);
473 		if (error)
474 			break;
475 	}
476 	aprint_debug("gmac_mapcache_fill(%p): limit=%zu used=%zu free=%zu\n",
477 	    mc, limit, mc->mc_used, mc->mc_free);
478 
479 	return error;
480 }
481 
482 bus_dmamap_t
483 gmac_mapcache_get(gmac_mapcache_t *mc)
484 {
485 	bus_dmamap_t map;
486 
487 	KASSERT(mc != NULL);
488 
489 	if (mc->mc_free == 0) {
490 		int error;
491 		if (mc->mc_used == mc->mc_max)
492 			return NULL;
493 		error = bus_dmamap_create(mc->mc_dmat, mc->mc_mapsize,
494 		    mc->mc_nsegs, mc->mc_mapsize, 0,
495 		    BUS_DMA_ALLOCNOW|BUS_DMA_NOWAIT,
496 		    &map);
497 		if (error)
498 			return NULL;
499 		KASSERT(mc->mc_maps[mc->mc_free] == NULL);
500 	} else {
501 		KASSERT(mc->mc_free <= mc->mc_max);
502 		map = mc->mc_maps[--mc->mc_free];
503 		mc->mc_maps[mc->mc_free] = NULL;
504 	}
505 	mc->mc_used++;
506 	KASSERT(map != NULL);
507 
508 	return map;
509 }
510 
511 void
512 gmac_mapcache_put(gmac_mapcache_t *mc, bus_dmamap_t map)
513 {
514 	KASSERT(mc->mc_free + mc->mc_used < mc->mc_max);
515 	KASSERT(mc->mc_maps[mc->mc_free] == NULL);
516 
517 	mc->mc_maps[mc->mc_free++] = map;
518 	mc->mc_used--;
519 }
520 
521 gmac_desc_t *
522 gmac_hwqueue_desc(gmac_hwqueue_t *hwq, size_t i)
523 {
524 	i += hwq->hwq_wptr;
525 	if (i >= hwq->hwq_size)
526 		i -= hwq->hwq_size;
527 	return hwq->hwq_base + i;
528 }
529 
530 static void
531 gmac_hwqueue_txconsume(gmac_hwqueue_t *hwq, const gmac_desc_t *d)
532 {
533 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
534 	struct ifnet *ifp;
535 	bus_dmamap_t map;
536 	struct mbuf *m;
537 
538 	IF_DEQUEUE(&hwq->hwq_ifq, m);
539 	KASSERT(m != NULL);
540 	map = M_GETCTX(m, bus_dmamap_t);
541 
542 	bus_dmamap_sync(hqm->hqm_dmat, map, 0, map->dm_mapsize,
543 	    BUS_DMASYNC_POSTWRITE);
544 	bus_dmamap_unload(hqm->hqm_dmat, map);
545 	M_SETCTX(m, NULL);
546 	gmac_mapcache_put(hqm->hqm_mc, map);
547 
548 	ifp = hwq->hwq_ifp;
549 	if_statinc(ifp, if_opackets);
550 	if_statiadd(ifp, if_obytes,	 m->m_pkthdr.len);
551 
552 	aprint_debug("gmac_hwqueue_txconsume(%p): %zu@%p: %s m=%p\n",
553 	    hwq, d - hwq->hwq_base, d, ifp->if_xname, m);
554 
555 	bpf_mtap(ifp, m, BPF_D_OUT);
556 	m_freem(m);
557 }
558 
559 void
560 gmac_hwqueue_sync(gmac_hwqueue_t *hwq)
561 {
562 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
563 	uint32_t v;
564 	uint16_t old_rptr;
565 	size_t rptr;
566 
567 	KASSERT(hqm->hqm_flags & HQM_PRODUCER);
568 
569 	old_rptr = hwq->hwq_rptr;
570 	v = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
571 	hwq->hwq_rptr = (v >>  0) & 0xffff;
572 	hwq->hwq_wptr = (v >> 16) & 0xffff;
573 
574 	if (old_rptr == hwq->hwq_rptr)
575 		return;
576 
577 	aprint_debug("gmac_hwqueue_sync(%p): entry rptr old=%u new=%u free=%u(%u)\n",
578 	    hwq, old_rptr, hwq->hwq_rptr, hwq->hwq_free,
579 	    hwq->hwq_size - hwq->hwq_free - 1);
580 
581 	hwq->hwq_free += (hwq->hwq_rptr - old_rptr) & (hwq->hwq_size - 1);
582 	for (rptr = old_rptr;
583 	     rptr != hwq->hwq_rptr;
584 	     rptr = (rptr + 1) & (hwq->hwq_size - 1)) {
585 		gmac_desc_t * const d = hwq->hwq_base + rptr;
586 		if (hqm->hqm_flags & HQM_TX) {
587 			bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
588 			    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
589 			    sizeof(gmac_desc_t),
590 			    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
591 			if (d->d_desc3 & htole32(DESC3_EOF))
592 				gmac_hwqueue_txconsume(hwq, d);
593 		} else {
594 			bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
595 			    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
596 			    sizeof(gmac_desc_t),
597 			    BUS_DMASYNC_POSTWRITE);
598 
599 			aprint_debug("gmac_hwqueue_sync(%p): %zu@%p=%#x/%#x/%#x/%#x\n",
600 			    hwq, rptr, d, d->d_desc0, d->d_desc1,
601 			    d->d_bufaddr, d->d_desc3);
602 			bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
603 			    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
604 			    sizeof(gmac_desc_t),
605 			    BUS_DMASYNC_PREWRITE);
606 		}
607 	}
608 
609 	aprint_debug("gmac_hwqueue_sync(%p): exit rptr old=%u new=%u free=%u(%u)\n",
610 	    hwq, old_rptr, hwq->hwq_rptr, hwq->hwq_free,
611 	    hwq->hwq_size - hwq->hwq_free - 1);
612 }
613 
614 void
615 gmac_hwqueue_produce(gmac_hwqueue_t *hwq, size_t count)
616 {
617 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
618 	uint16_t wptr;
619 	uint16_t rptr = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
620 
621 	KASSERT(count < hwq->hwq_free);
622 	KASSERT(hqm->hqm_flags & HQM_PRODUCER);
623 	KASSERT(hwq->hwq_wptr == bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0) >> 16);
624 
625 	aprint_debug("gmac_hwqueue_produce(%p, %zu): rptr=%u(%u) wptr old=%u",
626 	    hwq, count, hwq->hwq_rptr, rptr, hwq->hwq_wptr);
627 
628 	hwq->hwq_free -= count;
629 #if 1
630 	for (wptr = hwq->hwq_wptr;
631 	     count > 0;
632 	     count--, wptr = (wptr + 1) & (hwq->hwq_size - 1)) {
633 		KASSERT(((wptr + 1) & (hwq->hwq_size - 1)) != hwq->hwq_rptr);
634 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
635 		    sizeof(gmac_desc_t [hwq->hwq_qoff + wptr]),
636 		    sizeof(gmac_desc_t),
637 		    BUS_DMASYNC_PREWRITE);
638 	}
639 	KASSERT(count == 0);
640 	hwq->hwq_wptr = wptr;
641 #else
642 	if (hwq->hwq_wptr + count >= hwq->hwq_size) {
643 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
644 		    sizeof(gmac_desc_t [hwq->hwq_qoff + hwq->hwq_wptr]),
645 		    sizeof(gmac_desc_t [hwq->hwq_size - hwq->hwq_wptr]),
646 		    BUS_DMASYNC_PREWRITE);
647 		count -= hwq->hwq_size - hwq->hwq_wptr;
648 		hwq->hwq_wptr = 0;
649 	}
650 	if (count > 0) {
651 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
652 		    sizeof(gmac_desc_t [hwq->hwq_qoff + hwq->hwq_wptr]),
653 		    sizeof(gmac_desc_t [count]),
654 		    BUS_DMASYNC_PREWRITE);
655 		hwq->hwq_wptr += count;
656 		hwq->hwq_wptr &= (hwq->hwq_size - 1);
657 	}
658 #endif
659 
660 	/*
661 	 * Tell the h/w we've produced a few more descriptors.
662 	 * (don't bother writing the rptr since it's RO).
663 	 */
664 	bus_space_write_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0,
665 	    hwq->hwq_wptr << 16);
666 
667 	aprint_debug(" new=%u\n", hwq->hwq_wptr);
668 }
669 
670 size_t
671 gmac_rxproduce(gmac_hwqueue_t *hwq, size_t free_min)
672 {
673 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
674 	size_t i;
675 
676 	aprint_debug("gmac_rxproduce(%p): entry free=%u(%u) free_min=%zu ifq_len=%d\n",
677 	    hwq, hwq->hwq_free, hwq->hwq_size - hwq->hwq_free - 1,
678 	    free_min, hwq->hwq_ifq.ifq_len);
679 
680 	gmac_hwqueue_sync(hwq);
681 
682 	aprint_debug("gmac_rxproduce(%p): postsync free=%u(%u)\n",
683 	    hwq, hwq->hwq_free, hwq->hwq_size - hwq->hwq_free - 1);
684 
685 	for (i = 0; hwq->hwq_free > 0 && hwq->hwq_size - hwq->hwq_free - 1 < free_min; i++) {
686 		bus_dmamap_t map;
687 		gmac_desc_t * const d = gmac_hwqueue_desc(hwq, 0);
688 		struct mbuf *m, *m0;
689 		int error;
690 
691 		if (d->d_bufaddr && (le32toh(d->d_bufaddr) >> 16) != 0xdead) {
692 			gmac_hwqueue_produce(hwq, 1);
693 			continue;
694 		}
695 
696 		map = gmac_mapcache_get(hqm->hqm_mc);
697 		if (map == NULL)
698 			break;
699 
700 		KASSERT(map->dm_mapsize == 0);
701 
702 		m = m_gethdr(M_DONTWAIT, MT_DATA);
703 		if (m == NULL) {
704 			gmac_mapcache_put(hqm->hqm_mc, map);
705 			break;
706 		}
707 
708 		MCLGET(m, M_DONTWAIT);
709 		if ((m->m_flags & M_EXT) == 0) {
710 			m_free(m);
711 			gmac_mapcache_put(hqm->hqm_mc, map);
712 			break;
713 		}
714 		error = bus_dmamap_load(hqm->hqm_dmat, map, m->m_data,
715 		    MCLBYTES, NULL, BUS_DMA_READ|BUS_DMA_NOWAIT);
716 		if (error) {
717 			m_free(m);
718 			gmac_mapcache_put(hqm->hqm_mc, map);
719 			aprint_error("gmac0: "
720 			    "map %p(%zu): can't map rx mbuf(%p) wptr=%u: %d\n",
721 			    map, map->_dm_size, m, hwq->hwq_wptr, error);
722 			Debugger();
723 			break;
724 		}
725 		bus_dmamap_sync(hqm->hqm_dmat, map, 0, map->dm_mapsize,
726 		    BUS_DMASYNC_PREREAD);
727 		m->m_pkthdr.len = 0;
728 		M_SETCTX(m, map);
729 #if 0
730 		d->d_desc0   = htole32(map->dm_segs->ds_len);
731 #endif
732 		d->d_bufaddr = htole32(map->dm_segs->ds_addr);
733 		for (m0 = hwq->hwq_ifq.ifq_head; m0 != NULL; m0 = m0->m_nextpkt)
734 			KASSERT(m0 != m);
735 		m->m_len = d - hwq->hwq_base;
736 		IF_ENQUEUE(&hwq->hwq_ifq, m);
737 		aprint_debug(
738 		    "gmac_rxproduce(%p): m=%p %zu@%p=%#x/%#x/%#x/%#x\n", hwq,
739 		    m, d - hwq->hwq_base, d, d->d_desc0, d->d_desc1,
740 		    d->d_bufaddr, d->d_desc3);
741 		gmac_hwqueue_produce(hwq, 1);
742 	}
743 
744 	aprint_debug("gmac_rxproduce(%p): exit free=%u(%u) free_min=%zu ifq_len=%d\n",
745 	    hwq, hwq->hwq_free, hwq->hwq_size - hwq->hwq_free - 1,
746 	    free_min, hwq->hwq_ifq.ifq_len);
747 
748 	return i;
749 }
750 
751 static bool
752 gmac_hwqueue_rxconsume(gmac_hwqueue_t *hwq, const gmac_desc_t *d)
753 {
754 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
755 	struct ifnet * const ifp = hwq->hwq_ifp;
756 	size_t buflen = d->d_desc1 & 0xffff;
757 	bus_dmamap_t map;
758 	struct mbuf *m, *last_m, **mp;
759 	size_t depth;
760 
761 	KASSERT(ifp != NULL);
762 
763 	aprint_debug("gmac_hwqueue_rxconsume(%p): entry\n", hwq);
764 
765 	aprint_debug("gmac_hwqueue_rxconsume(%p): ifp=%p(%s): %#x/%#x/%#x/%#x\n",
766 	    hwq, hwq->hwq_ifp, hwq->hwq_ifp->if_xname,
767 	    d->d_desc0, d->d_desc1, d->d_bufaddr, d->d_desc3);
768 
769 	if (d->d_bufaddr == 0 || d->d_bufaddr == 0xdeadbeef)
770 		return false;
771 
772 	/*
773 	 * First we have to find this mbuf in the software free queue
774 	 * (the producer of the mbufs) and remove it.
775 	 */
776 	KASSERT(hwq->hwq_producer->hwq_free != hwq->hwq_producer->hwq_size - 1);
777 	for (mp = &hwq->hwq_producer->hwq_ifq.ifq_head, last_m = NULL, depth=0;
778 	     (m = *mp) != NULL;
779 	     last_m = m, mp = &m->m_nextpkt, depth++) {
780 		map = M_GETCTX(m, bus_dmamap_t);
781 		KASSERT(map != NULL);
782 		KASSERT(map->dm_nsegs == 1);
783 		aprint_debug("gmac_hwqueue_rxconsume(%p): ifq[%zu]=%p(@%#zx) %d@swfq\n",
784 		    hwq, depth, m, map->dm_segs->ds_addr, m->m_len);
785 		if (le32toh(d->d_bufaddr) == map->dm_segs->ds_addr) {
786 			*mp = m->m_nextpkt;
787 			if (hwq->hwq_producer->hwq_ifq.ifq_tail == m)
788 				hwq->hwq_producer->hwq_ifq.ifq_tail = last_m;
789 			hwq->hwq_producer->hwq_ifq.ifq_len--;
790 			break;
791 		}
792 	}
793 	aprint_debug("gmac_hwqueue_rxconsume(%p): ifp=%p(%s) m=%p@%zu",
794 	    hwq, hwq->hwq_ifp, hwq->hwq_ifp->if_xname, m, depth);
795 	if (m)
796 		aprint_debug(" swfq[%d]=%#x\n", m->m_len,
797 		    hwq->hwq_producer->hwq_base[m->m_len].d_bufaddr);
798 	aprint_debug("\n");
799 	KASSERT(m != NULL);
800 
801 	{
802 		struct mbuf *m0;
803 		for (m0 = hwq->hwq_producer->hwq_ifq.ifq_head; m0 != NULL; m0 = m0->m_nextpkt)
804 			KASSERT(m0 != m);
805 	}
806 
807 	KASSERT(hwq->hwq_producer->hwq_base[m->m_len].d_bufaddr == d->d_bufaddr);
808 	hwq->hwq_producer->hwq_base[m->m_len].d_bufaddr = htole32(0xdead0000 | m->m_len);
809 
810 	m->m_len = buflen;
811 	if (d->d_desc3 & DESC3_SOF) {
812 		KASSERT(hwq->hwq_rxmbuf == NULL);
813 		m->m_pkthdr.len = buflen;
814 		buflen += 2;	/* account for the pad */
815 		/* only modify m->m_data after we know mbuf is good. */
816 	} else {
817 		KASSERT(hwq->hwq_rxmbuf != NULL);
818 		hwq->hwq_rxmbuf->m_pkthdr.len += buflen;
819 	}
820 
821 	map = M_GETCTX(m, bus_dmamap_t);
822 
823 	/*
824 	 * Sync the buffer contents, unload the dmamap, and save it away.
825 	 */
826 	bus_dmamap_sync(hqm->hqm_dmat, map, 0, buflen, BUS_DMASYNC_POSTREAD);
827 	bus_dmamap_unload(hqm->hqm_dmat, map);
828 	M_SETCTX(m, NULL);
829 	gmac_mapcache_put(hqm->hqm_mc, map);
830 
831 	/*
832 	 * Now we build our new packet chain by tacking this on the end.
833 	 */
834 	*hwq->hwq_mp = m;
835 	if ((d->d_desc3 & DESC3_EOF) == 0) {
836 		/*
837 		 * Not last frame, so make sure the next gets appended right.
838 		 */
839 		hwq->hwq_mp = &m->m_next;
840 		return true;
841 	}
842 
843 #if 0
844 	/*
845 	 * We have a complete frame, let's try to deliver it.
846 	 */
847 	m->m_len -= ETHER_CRC_LEN;	/* remove the CRC from the end */
848 #endif
849 
850 	/*
851 	 * Now get the whole chain.
852 	 */
853 	m = hwq->hwq_rxmbuf;
854 	m_set_rcvif(m, ifp);	/* set receive interface */
855 	switch (DESC0_RXSTS_GET(d->d_desc0)) {
856 	case DESC0_RXSTS_GOOD:
857 	case DESC0_RXSTS_LONG:
858 		m->m_data += 2;
859 		if_percpuq_enqueue(ifp->if_percpuq, m);
860 		break;
861 	default:
862 		if_statinc(ifp, if_ierrors);
863 		m_freem(m);
864 		break;
865 	}
866 	hwq->hwq_rxmbuf = NULL;
867 	hwq->hwq_mp = &hwq->hwq_rxmbuf;
868 
869 	return true;
870 }
871 
872 size_t
873 gmac_hwqueue_consume(gmac_hwqueue_t *hwq, size_t free_min)
874 {
875 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
876 	gmac_desc_t d;
877 	uint32_t v;
878 	uint16_t rptr;
879 	size_t i;
880 
881 	KASSERT((hqm->hqm_flags & HQM_PRODUCER) == 0);
882 
883 	aprint_debug("gmac_hwqueue_consume(%p): entry\n", hwq);
884 
885 
886 	v = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
887 	rptr = (v >>  0) & 0xffff;
888 	hwq->hwq_wptr = (v >> 16) & 0xffff;
889 	KASSERT(rptr == hwq->hwq_rptr);
890 	if (rptr == hwq->hwq_wptr)
891 		return 0;
892 
893 	i = 0;
894 	for (; rptr != hwq->hwq_wptr; rptr = (rptr + 1) & (hwq->hwq_size - 1)) {
895 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
896 		    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
897 		    sizeof(gmac_desc_t),
898 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
899 		d.d_desc0   = le32toh(hwq->hwq_base[rptr].d_desc0);
900 		d.d_desc1   = le32toh(hwq->hwq_base[rptr].d_desc1);
901 		d.d_bufaddr = le32toh(hwq->hwq_base[rptr].d_bufaddr);
902 		d.d_desc3   = le32toh(hwq->hwq_base[rptr].d_desc3);
903 		hwq->hwq_base[rptr].d_desc0 = 0;
904 		hwq->hwq_base[rptr].d_desc1 = 0;
905 		hwq->hwq_base[rptr].d_bufaddr = 0xdeadbeef;
906 		hwq->hwq_base[rptr].d_desc3 = 0;
907 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap,
908 		    sizeof(gmac_desc_t [hwq->hwq_qoff + rptr]),
909 		    sizeof(gmac_desc_t),
910 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
911 
912 		aprint_debug("gmac_hwqueue_consume(%p): rptr=%u\n",
913 		    hwq, rptr);
914 		if (!gmac_hwqueue_rxconsume(hwq, &d)) {
915 			rptr = (rptr + 1) & (hwq->hwq_size - 1);
916 			i += gmac_rxproduce(hwq->hwq_producer, free_min);
917 			break;
918 		}
919 	}
920 
921 	/*
922 	 * Update hardware's copy of rptr.  (wptr is RO).
923 	 */
924 	aprint_debug("gmac_hwqueue_consume(%p): rptr old=%u new=%u wptr=%u\n",
925 	    hwq, hwq->hwq_rptr, rptr, hwq->hwq_wptr);
926 	bus_space_write_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0, rptr);
927 	hwq->hwq_rptr = rptr;
928 
929 	aprint_debug("gmac_hwqueue_consume(%p): exit\n", hwq);
930 
931 	return i;
932 }
933 
934 void
935 gmac_hwqmem_destroy(gmac_hwqmem_t *hqm)
936 {
937 	if (hqm->hqm_nsegs) {
938 		if (hqm->hqm_base) {
939 			if (hqm->hqm_dmamap) {
940 				if (hqm->hqm_dmamap->dm_mapsize) {
941 					bus_dmamap_unload(hqm->hqm_dmat,
942 					    hqm->hqm_dmamap);
943 				}
944 				bus_dmamap_destroy(hqm->hqm_dmat,
945 				     hqm->hqm_dmamap);
946 			}
947 			bus_dmamem_unmap(hqm->hqm_dmat, hqm->hqm_base,
948 			    hqm->hqm_memsize);
949 		}
950 		bus_dmamem_free(hqm->hqm_dmat, hqm->hqm_segs, hqm->hqm_nsegs);
951 	}
952 
953 	kmem_free(hqm, sizeof(*hqm));
954 }
955 
956 gmac_hwqmem_t *
957 gmac_hwqmem_create(gmac_mapcache_t *mc, size_t ndesc, size_t nqueue, int flags)
958 {
959 	gmac_hwqmem_t *hqm;
960 	int error;
961 
962 	KASSERT(ndesc > 0 && ndesc <= 2048);
963 	KASSERT((ndesc & (ndesc - 1)) == 0);
964 
965 	hqm = kmem_zalloc(sizeof(*hqm), KM_SLEEP);
966 	hqm->hqm_memsize = nqueue * sizeof(gmac_desc_t [ndesc]);
967 	hqm->hqm_mc = mc;
968 	hqm->hqm_dmat = mc->mc_dmat;
969 	hqm->hqm_ndesc = ndesc;
970 	hqm->hqm_nqueue = nqueue;
971 	hqm->hqm_flags = flags;
972 
973 	error = bus_dmamem_alloc(hqm->hqm_dmat, hqm->hqm_memsize, 0, 0,
974 	    hqm->hqm_segs, 1, &hqm->hqm_nsegs, BUS_DMA_WAITOK);
975 	if (error) {
976 		KASSERT(error == 0);
977 		goto failed;
978 	}
979 	KASSERT(hqm->hqm_nsegs == 1);
980 	error = bus_dmamem_map(hqm->hqm_dmat, hqm->hqm_segs, hqm->hqm_nsegs,
981 	    hqm->hqm_memsize, (void **)&hqm->hqm_base, BUS_DMA_WAITOK);
982 	if (error) {
983 		KASSERT(error == 0);
984 		goto failed;
985 	}
986 	error = bus_dmamap_create(hqm->hqm_dmat, hqm->hqm_memsize,
987 	    hqm->hqm_nsegs, hqm->hqm_memsize, 0,
988 	    BUS_DMA_WAITOK|BUS_DMA_ALLOCNOW, &hqm->hqm_dmamap);
989 	if (error) {
990 		KASSERT(error == 0);
991 		goto failed;
992 	}
993 	error = bus_dmamap_load(hqm->hqm_dmat, hqm->hqm_dmamap, hqm->hqm_base,
994 	    hqm->hqm_memsize, NULL,
995 	    BUS_DMA_WAITOK|BUS_DMA_WRITE|BUS_DMA_READ|BUS_DMA_COHERENT);
996 	if (error) {
997 		aprint_debug("gmac_hwqmem_create: ds_addr=%zu ds_len=%zu\n",
998 		    hqm->hqm_segs->ds_addr, hqm->hqm_segs->ds_len);
999 		aprint_debug("gmac_hwqmem_create: bus_dmamap_load: %d\n", error);
1000 		KASSERT(error == 0);
1001 		goto failed;
1002 	}
1003 
1004 	memset(hqm->hqm_base, 0, hqm->hqm_memsize);
1005 	if ((flags & HQM_PRODUCER) == 0)
1006 		bus_dmamap_sync(hqm->hqm_dmat, hqm->hqm_dmamap, 0,
1007 		    hqm->hqm_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1008 
1009 	return hqm;
1010 
1011 failed:
1012 	gmac_hwqmem_destroy(hqm);
1013 	return NULL;
1014 }
1015 
1016 void
1017 gmac_hwqueue_destroy(gmac_hwqueue_t *hwq)
1018 {
1019 	gmac_hwqmem_t * const hqm = hwq->hwq_hqm;
1020 	KASSERT(hqm->hqm_refs & hwq->hwq_ref);
1021 	hqm->hqm_refs &= ~hwq->hwq_ref;
1022 	for (;;) {
1023 		struct mbuf *m;
1024 		bus_dmamap_t map;
1025 		IF_DEQUEUE(&hwq->hwq_ifq, m);
1026 		if (m == NULL)
1027 			break;
1028 		map = M_GETCTX(m, bus_dmamap_t);
1029 		bus_dmamap_unload(hqm->hqm_dmat, map);
1030 		gmac_mapcache_put(hqm->hqm_mc, map);
1031 		m_freem(m);
1032 	}
1033 	kmem_free(hwq, sizeof(*hwq));
1034 }
1035 
1036 gmac_hwqueue_t *
1037 gmac_hwqueue_create(gmac_hwqmem_t *hqm,
1038     bus_space_tag_t iot, bus_space_handle_t ioh,
1039     bus_size_t qrwptr, bus_size_t qbase,
1040     size_t qno)
1041 {
1042 	const size_t log2_memsize = ffs(hqm->hqm_ndesc) - 1;
1043 	gmac_hwqueue_t *hwq;
1044 	uint32_t v;
1045 
1046 	KASSERT(qno < hqm->hqm_nqueue);
1047 	KASSERT((hqm->hqm_refs & (1 << qno)) == 0);
1048 
1049 	hwq = kmem_zalloc(sizeof(*hwq), KM_SLEEP);
1050 	hwq->hwq_size = hqm->hqm_ndesc;
1051 	hwq->hwq_iot = iot;
1052 	bus_space_subregion(iot, ioh, qrwptr, sizeof(uint32_t),
1053 	    &hwq->hwq_qrwptr_ioh);
1054 
1055 	hwq->hwq_hqm = hqm;
1056 	hwq->hwq_ref = 1 << qno;
1057 	hqm->hqm_refs |= hwq->hwq_ref;
1058 	hwq->hwq_qoff = hqm->hqm_ndesc * qno;
1059 	hwq->hwq_base = hqm->hqm_base + hwq->hwq_qoff;
1060 
1061 	if (qno == 0) {
1062 		bus_space_write_4(hwq->hwq_iot, ioh, qbase,
1063 		     hqm->hqm_dmamap->dm_segs[0].ds_addr | (log2_memsize));
1064 	}
1065 
1066 	v = bus_space_read_4(hwq->hwq_iot, hwq->hwq_qrwptr_ioh, 0);
1067 	hwq->hwq_rptr = (v >>  0) & 0xffff;
1068 	hwq->hwq_wptr = (v >> 16) & 0xffff;
1069 
1070 	aprint_debug("gmac_hwqueue_create: %p: qrwptr=%zu(%#zx) wptr=%u rptr=%u"
1071 	    " base=%p@%#zx(%#x) qno=%zu\n",
1072 	    hwq, qrwptr, hwq->hwq_qrwptr_ioh, hwq->hwq_wptr, hwq->hwq_rptr,
1073 	    hwq->hwq_base,
1074 	    hqm->hqm_segs->ds_addr + sizeof(gmac_desc_t [hwq->hwq_qoff]),
1075 	    bus_space_read_4(hwq->hwq_iot, ioh, qbase), qno);
1076 
1077 	hwq->hwq_free = hwq->hwq_size - 1;
1078 	hwq->hwq_ifq.ifq_maxlen = hwq->hwq_free;
1079 	hwq->hwq_mp = &hwq->hwq_rxmbuf;
1080 
1081 	return hwq;
1082 }
1083