xref: /linux/drivers/net/dsa/mv88e6xxx/global1.c (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Marvell 88E6xxx Switch Global (1) Registers support
4  *
5  * Copyright (c) 2008 Marvell Semiconductor
6  *
7  * Copyright (c) 2016-2017 Savoir-faire Linux Inc.
8  *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
9  */
10 
11 #include <linux/bitfield.h>
12 
13 #include "chip.h"
14 #include "global1.h"
15 
16 int mv88e6xxx_g1_read(struct mv88e6xxx_chip *chip, int reg, u16 *val)
17 {
18 	int addr = chip->info->global1_addr;
19 
20 	return mv88e6xxx_read(chip, addr, reg, val);
21 }
22 
23 int mv88e6xxx_g1_write(struct mv88e6xxx_chip *chip, int reg, u16 val)
24 {
25 	int addr = chip->info->global1_addr;
26 
27 	return mv88e6xxx_write(chip, addr, reg, val);
28 }
29 
30 int mv88e6xxx_g1_wait_bit(struct mv88e6xxx_chip *chip, int reg, int
31 			  bit, int val)
32 {
33 	return mv88e6xxx_wait_bit(chip, chip->info->global1_addr, reg,
34 				  bit, val);
35 }
36 
37 int mv88e6xxx_g1_wait_mask(struct mv88e6xxx_chip *chip, int reg,
38 			   u16 mask, u16 val)
39 {
40 	return mv88e6xxx_wait_mask(chip, chip->info->global1_addr, reg,
41 				   mask, val);
42 }
43 
44 /* Offset 0x00: Switch Global Status Register */
45 
46 static int mv88e6185_g1_wait_ppu_disabled(struct mv88e6xxx_chip *chip)
47 {
48 	return mv88e6xxx_g1_wait_mask(chip, MV88E6XXX_G1_STS,
49 				      MV88E6185_G1_STS_PPU_STATE_MASK,
50 				      MV88E6185_G1_STS_PPU_STATE_DISABLED);
51 }
52 
53 static int mv88e6185_g1_wait_ppu_polling(struct mv88e6xxx_chip *chip)
54 {
55 	return mv88e6xxx_g1_wait_mask(chip, MV88E6XXX_G1_STS,
56 				      MV88E6185_G1_STS_PPU_STATE_MASK,
57 				      MV88E6185_G1_STS_PPU_STATE_POLLING);
58 }
59 
60 static int mv88e6352_g1_wait_ppu_polling(struct mv88e6xxx_chip *chip)
61 {
62 	int bit = __bf_shf(MV88E6352_G1_STS_PPU_STATE);
63 
64 	return mv88e6xxx_g1_wait_bit(chip, MV88E6XXX_G1_STS, bit, 1);
65 }
66 
67 static int mv88e6xxx_g1_wait_init_ready(struct mv88e6xxx_chip *chip)
68 {
69 	int bit = __bf_shf(MV88E6XXX_G1_STS_INIT_READY);
70 
71 	/* Wait up to 1 second for the switch to be ready. The InitReady bit 11
72 	 * is set to a one when all units inside the device (ATU, VTU, etc.)
73 	 * have finished their initialization and are ready to accept frames.
74 	 */
75 	return mv88e6xxx_g1_wait_bit(chip, MV88E6XXX_G1_STS, bit, 1);
76 }
77 
78 void mv88e6xxx_g1_wait_eeprom_done(struct mv88e6xxx_chip *chip)
79 {
80 	const unsigned long timeout = jiffies + 1 * HZ;
81 	u16 val;
82 	int err;
83 
84 	/* Wait up to 1 second for the switch to finish reading the
85 	 * EEPROM.
86 	 */
87 	while (time_before(jiffies, timeout)) {
88 		err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_STS, &val);
89 		if (err) {
90 			dev_err(chip->dev, "Error reading status");
91 			return;
92 		}
93 
94 		/* If the switch is still resetting, it may not
95 		 * respond on the bus, and so MDIO read returns
96 		 * 0xffff. Differentiate between that, and waiting for
97 		 * the EEPROM to be done by bit 0 being set.
98 		 */
99 		if (val != 0xffff &&
100 		    val & BIT(MV88E6XXX_G1_STS_IRQ_EEPROM_DONE))
101 			return;
102 
103 		usleep_range(1000, 2000);
104 	}
105 
106 	dev_err(chip->dev, "Timeout waiting for EEPROM done");
107 }
108 
109 /* Offset 0x01: Switch MAC Address Register Bytes 0 & 1
110  * Offset 0x02: Switch MAC Address Register Bytes 2 & 3
111  * Offset 0x03: Switch MAC Address Register Bytes 4 & 5
112  */
113 int mv88e6xxx_g1_set_switch_mac(struct mv88e6xxx_chip *chip, u8 *addr)
114 {
115 	u16 reg;
116 	int err;
117 
118 	reg = (addr[0] << 8) | addr[1];
119 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_MAC_01, reg);
120 	if (err)
121 		return err;
122 
123 	reg = (addr[2] << 8) | addr[3];
124 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_MAC_23, reg);
125 	if (err)
126 		return err;
127 
128 	reg = (addr[4] << 8) | addr[5];
129 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_MAC_45, reg);
130 	if (err)
131 		return err;
132 
133 	return 0;
134 }
135 
136 /* Offset 0x04: Switch Global Control Register */
137 
138 int mv88e6185_g1_reset(struct mv88e6xxx_chip *chip)
139 {
140 	u16 val;
141 	int err;
142 
143 	/* Set the SWReset bit 15 along with the PPUEn bit 14, to also restart
144 	 * the PPU, including re-doing PHY detection and initialization
145 	 */
146 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL1, &val);
147 	if (err)
148 		return err;
149 
150 	val |= MV88E6XXX_G1_CTL1_SW_RESET;
151 	val |= MV88E6XXX_G1_CTL1_PPU_ENABLE;
152 
153 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_CTL1, val);
154 	if (err)
155 		return err;
156 
157 	err = mv88e6xxx_g1_wait_init_ready(chip);
158 	if (err)
159 		return err;
160 
161 	return mv88e6185_g1_wait_ppu_polling(chip);
162 }
163 
164 int mv88e6250_g1_reset(struct mv88e6xxx_chip *chip)
165 {
166 	u16 val;
167 	int err;
168 
169 	/* Set the SWReset bit 15 */
170 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL1, &val);
171 	if (err)
172 		return err;
173 
174 	val |= MV88E6XXX_G1_CTL1_SW_RESET;
175 
176 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_CTL1, val);
177 	if (err)
178 		return err;
179 
180 	return mv88e6xxx_g1_wait_init_ready(chip);
181 }
182 
183 int mv88e6352_g1_reset(struct mv88e6xxx_chip *chip)
184 {
185 	int err;
186 
187 	err = mv88e6250_g1_reset(chip);
188 	if (err)
189 		return err;
190 
191 	return mv88e6352_g1_wait_ppu_polling(chip);
192 }
193 
194 int mv88e6185_g1_ppu_enable(struct mv88e6xxx_chip *chip)
195 {
196 	u16 val;
197 	int err;
198 
199 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL1, &val);
200 	if (err)
201 		return err;
202 
203 	val |= MV88E6XXX_G1_CTL1_PPU_ENABLE;
204 
205 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_CTL1, val);
206 	if (err)
207 		return err;
208 
209 	return mv88e6185_g1_wait_ppu_polling(chip);
210 }
211 
212 int mv88e6185_g1_ppu_disable(struct mv88e6xxx_chip *chip)
213 {
214 	u16 val;
215 	int err;
216 
217 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL1, &val);
218 	if (err)
219 		return err;
220 
221 	val &= ~MV88E6XXX_G1_CTL1_PPU_ENABLE;
222 
223 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_CTL1, val);
224 	if (err)
225 		return err;
226 
227 	return mv88e6185_g1_wait_ppu_disabled(chip);
228 }
229 
230 int mv88e6185_g1_set_max_frame_size(struct mv88e6xxx_chip *chip, int mtu)
231 {
232 	u16 val;
233 	int err;
234 
235 	mtu += ETH_HLEN + ETH_FCS_LEN;
236 
237 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL1, &val);
238 	if (err)
239 		return err;
240 
241 	val &= ~MV88E6185_G1_CTL1_MAX_FRAME_1632;
242 
243 	if (mtu > 1518)
244 		val |= MV88E6185_G1_CTL1_MAX_FRAME_1632;
245 
246 	return mv88e6xxx_g1_write(chip, MV88E6XXX_G1_CTL1, val);
247 }
248 
249 /* Offset 0x10: IP-PRI Mapping Register 0
250  * Offset 0x11: IP-PRI Mapping Register 1
251  * Offset 0x12: IP-PRI Mapping Register 2
252  * Offset 0x13: IP-PRI Mapping Register 3
253  * Offset 0x14: IP-PRI Mapping Register 4
254  * Offset 0x15: IP-PRI Mapping Register 5
255  * Offset 0x16: IP-PRI Mapping Register 6
256  * Offset 0x17: IP-PRI Mapping Register 7
257  */
258 
259 int mv88e6085_g1_ip_pri_map(struct mv88e6xxx_chip *chip)
260 {
261 	int err;
262 
263 	/* Reset the IP TOS/DiffServ/Traffic priorities to defaults */
264 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_0, 0x0000);
265 	if (err)
266 		return err;
267 
268 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_1, 0x0000);
269 	if (err)
270 		return err;
271 
272 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_2, 0x5555);
273 	if (err)
274 		return err;
275 
276 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_3, 0x5555);
277 	if (err)
278 		return err;
279 
280 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_4, 0xaaaa);
281 	if (err)
282 		return err;
283 
284 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_5, 0xaaaa);
285 	if (err)
286 		return err;
287 
288 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_6, 0xffff);
289 	if (err)
290 		return err;
291 
292 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IP_PRI_7, 0xffff);
293 	if (err)
294 		return err;
295 
296 	return 0;
297 }
298 
299 /* Offset 0x18: IEEE-PRI Register */
300 
301 int mv88e6085_g1_ieee_pri_map(struct mv88e6xxx_chip *chip)
302 {
303 	/* Reset the IEEE Tag priorities to defaults */
304 	return mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IEEE_PRI, 0xfa41);
305 }
306 
307 int mv88e6250_g1_ieee_pri_map(struct mv88e6xxx_chip *chip)
308 {
309 	/* Reset the IEEE Tag priorities to defaults */
310 	return mv88e6xxx_g1_write(chip, MV88E6XXX_G1_IEEE_PRI, 0xfa50);
311 }
312 
313 /* Offset 0x1a: Monitor Control */
314 /* Offset 0x1a: Monitor & MGMT Control on some devices */
315 
316 int mv88e6095_g1_set_egress_port(struct mv88e6xxx_chip *chip,
317 				 enum mv88e6xxx_egress_direction direction,
318 				 int port)
319 {
320 	u16 reg;
321 	int err;
322 
323 	err = mv88e6xxx_g1_read(chip, MV88E6185_G1_MONITOR_CTL, &reg);
324 	if (err)
325 		return err;
326 
327 	switch (direction) {
328 	case MV88E6XXX_EGRESS_DIR_INGRESS:
329 		reg &= ~MV88E6185_G1_MONITOR_CTL_INGRESS_DEST_MASK;
330 		reg |= port <<
331 		       __bf_shf(MV88E6185_G1_MONITOR_CTL_INGRESS_DEST_MASK);
332 		break;
333 	case MV88E6XXX_EGRESS_DIR_EGRESS:
334 		reg &= ~MV88E6185_G1_MONITOR_CTL_EGRESS_DEST_MASK;
335 		reg |= port <<
336 		       __bf_shf(MV88E6185_G1_MONITOR_CTL_EGRESS_DEST_MASK);
337 		break;
338 	default:
339 		return -EINVAL;
340 	}
341 
342 	return mv88e6xxx_g1_write(chip, MV88E6185_G1_MONITOR_CTL, reg);
343 }
344 
345 /* Older generations also call this the ARP destination. It has been
346  * generalized in more modern devices such that more than ARP can
347  * egress it
348  */
349 int mv88e6095_g1_set_cpu_port(struct mv88e6xxx_chip *chip, int port)
350 {
351 	u16 reg;
352 	int err;
353 
354 	err = mv88e6xxx_g1_read(chip, MV88E6185_G1_MONITOR_CTL, &reg);
355 	if (err)
356 		return err;
357 
358 	reg &= ~MV88E6185_G1_MONITOR_CTL_ARP_DEST_MASK;
359 	reg |= port << __bf_shf(MV88E6185_G1_MONITOR_CTL_ARP_DEST_MASK);
360 
361 	return mv88e6xxx_g1_write(chip, MV88E6185_G1_MONITOR_CTL, reg);
362 }
363 
364 static int mv88e6390_g1_monitor_write(struct mv88e6xxx_chip *chip,
365 				      u16 pointer, u8 data)
366 {
367 	u16 reg;
368 
369 	reg = MV88E6390_G1_MONITOR_MGMT_CTL_UPDATE | pointer | data;
370 
371 	return mv88e6xxx_g1_write(chip, MV88E6390_G1_MONITOR_MGMT_CTL, reg);
372 }
373 
374 int mv88e6390_g1_set_egress_port(struct mv88e6xxx_chip *chip,
375 				 enum mv88e6xxx_egress_direction direction,
376 				 int port)
377 {
378 	u16 ptr;
379 
380 	switch (direction) {
381 	case MV88E6XXX_EGRESS_DIR_INGRESS:
382 		ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_INGRESS_DEST;
383 		break;
384 	case MV88E6XXX_EGRESS_DIR_EGRESS:
385 		ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_EGRESS_DEST;
386 		break;
387 	default:
388 		return -EINVAL;
389 	}
390 
391 	return mv88e6390_g1_monitor_write(chip, ptr, port);
392 }
393 
394 int mv88e6390_g1_set_cpu_port(struct mv88e6xxx_chip *chip, int port)
395 {
396 	u16 ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_CPU_DEST;
397 
398 	/* Use the default high priority for management frames sent to
399 	 * the CPU.
400 	 */
401 	port |= MV88E6390_G1_MONITOR_MGMT_CTL_PTR_CPU_DEST_MGMTPRI;
402 
403 	return mv88e6390_g1_monitor_write(chip, ptr, port);
404 }
405 
406 int mv88e6390_g1_set_ptp_cpu_port(struct mv88e6xxx_chip *chip, int port)
407 {
408 	u16 ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_PTP_CPU_DEST;
409 
410 	/* Use the default high priority for PTP frames sent to
411 	 * the CPU.
412 	 */
413 	port |= MV88E6390_G1_MONITOR_MGMT_CTL_PTR_CPU_DEST_MGMTPRI;
414 
415 	return mv88e6390_g1_monitor_write(chip, ptr, port);
416 }
417 
418 int mv88e6390_g1_mgmt_rsvd2cpu(struct mv88e6xxx_chip *chip)
419 {
420 	u16 ptr;
421 	int err;
422 
423 	/* 01:80:c2:00:00:00-01:80:c2:00:00:07 are Management */
424 	ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_0180C200000XLO;
425 	err = mv88e6390_g1_monitor_write(chip, ptr, 0xff);
426 	if (err)
427 		return err;
428 
429 	/* 01:80:c2:00:00:08-01:80:c2:00:00:0f are Management */
430 	ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_0180C200000XHI;
431 	err = mv88e6390_g1_monitor_write(chip, ptr, 0xff);
432 	if (err)
433 		return err;
434 
435 	/* 01:80:c2:00:00:20-01:80:c2:00:00:27 are Management */
436 	ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_0180C200002XLO;
437 	err = mv88e6390_g1_monitor_write(chip, ptr, 0xff);
438 	if (err)
439 		return err;
440 
441 	/* 01:80:c2:00:00:28-01:80:c2:00:00:2f are Management */
442 	ptr = MV88E6390_G1_MONITOR_MGMT_CTL_PTR_0180C200002XHI;
443 	err = mv88e6390_g1_monitor_write(chip, ptr, 0xff);
444 	if (err)
445 		return err;
446 
447 	return 0;
448 }
449 
450 /* Offset 0x1c: Global Control 2 */
451 
452 static int mv88e6xxx_g1_ctl2_mask(struct mv88e6xxx_chip *chip, u16 mask,
453 				  u16 val)
454 {
455 	u16 reg;
456 	int err;
457 
458 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL2, &reg);
459 	if (err)
460 		return err;
461 
462 	reg &= ~mask;
463 	reg |= val & mask;
464 
465 	return mv88e6xxx_g1_write(chip, MV88E6XXX_G1_CTL2, reg);
466 }
467 
468 int mv88e6185_g1_set_cascade_port(struct mv88e6xxx_chip *chip, int port)
469 {
470 	const u16 mask = MV88E6185_G1_CTL2_CASCADE_PORT_MASK;
471 
472 	return mv88e6xxx_g1_ctl2_mask(chip, mask, port << __bf_shf(mask));
473 }
474 
475 int mv88e6085_g1_rmu_disable(struct mv88e6xxx_chip *chip)
476 {
477 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6085_G1_CTL2_P10RM |
478 				      MV88E6085_G1_CTL2_RM_ENABLE, 0);
479 }
480 
481 int mv88e6352_g1_rmu_disable(struct mv88e6xxx_chip *chip)
482 {
483 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6352_G1_CTL2_RMU_MODE_MASK,
484 				      MV88E6352_G1_CTL2_RMU_MODE_DISABLED);
485 }
486 
487 int mv88e6390_g1_rmu_disable(struct mv88e6xxx_chip *chip)
488 {
489 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6390_G1_CTL2_RMU_MODE_MASK,
490 				      MV88E6390_G1_CTL2_RMU_MODE_DISABLED);
491 }
492 
493 int mv88e6390_g1_stats_set_histogram(struct mv88e6xxx_chip *chip)
494 {
495 	return mv88e6xxx_g1_ctl2_mask(chip, MV88E6390_G1_CTL2_HIST_MODE_MASK,
496 				      MV88E6390_G1_CTL2_HIST_MODE_RX |
497 				      MV88E6390_G1_CTL2_HIST_MODE_TX);
498 }
499 
500 int mv88e6xxx_g1_set_device_number(struct mv88e6xxx_chip *chip, int index)
501 {
502 	return mv88e6xxx_g1_ctl2_mask(chip,
503 				      MV88E6XXX_G1_CTL2_DEVICE_NUMBER_MASK,
504 				      index);
505 }
506 
507 /* Offset 0x1d: Statistics Operation 2 */
508 
509 static int mv88e6xxx_g1_stats_wait(struct mv88e6xxx_chip *chip)
510 {
511 	int bit = __bf_shf(MV88E6XXX_G1_STATS_OP_BUSY);
512 
513 	return mv88e6xxx_g1_wait_bit(chip, MV88E6XXX_G1_STATS_OP, bit, 0);
514 }
515 
516 int mv88e6095_g1_stats_set_histogram(struct mv88e6xxx_chip *chip)
517 {
518 	u16 val;
519 	int err;
520 
521 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_STATS_OP, &val);
522 	if (err)
523 		return err;
524 
525 	val |= MV88E6XXX_G1_STATS_OP_HIST_RX_TX;
526 
527 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_STATS_OP, val);
528 
529 	return err;
530 }
531 
532 int mv88e6xxx_g1_stats_snapshot(struct mv88e6xxx_chip *chip, int port)
533 {
534 	int err;
535 
536 	/* Snapshot the hardware statistics counters for this port. */
537 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_STATS_OP,
538 				 MV88E6XXX_G1_STATS_OP_BUSY |
539 				 MV88E6XXX_G1_STATS_OP_CAPTURE_PORT |
540 				 MV88E6XXX_G1_STATS_OP_HIST_RX_TX | port);
541 	if (err)
542 		return err;
543 
544 	/* Wait for the snapshotting to complete. */
545 	return mv88e6xxx_g1_stats_wait(chip);
546 }
547 
548 int mv88e6320_g1_stats_snapshot(struct mv88e6xxx_chip *chip, int port)
549 {
550 	port = (port + 1) << 5;
551 
552 	return mv88e6xxx_g1_stats_snapshot(chip, port);
553 }
554 
555 int mv88e6390_g1_stats_snapshot(struct mv88e6xxx_chip *chip, int port)
556 {
557 	int err;
558 
559 	port = (port + 1) << 5;
560 
561 	/* Snapshot the hardware statistics counters for this port. */
562 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_STATS_OP,
563 				 MV88E6XXX_G1_STATS_OP_BUSY |
564 				 MV88E6XXX_G1_STATS_OP_CAPTURE_PORT | port);
565 	if (err)
566 		return err;
567 
568 	/* Wait for the snapshotting to complete. */
569 	return mv88e6xxx_g1_stats_wait(chip);
570 }
571 
572 void mv88e6xxx_g1_stats_read(struct mv88e6xxx_chip *chip, int stat, u32 *val)
573 {
574 	u32 value;
575 	u16 reg;
576 	int err;
577 
578 	*val = 0;
579 
580 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_STATS_OP,
581 				 MV88E6XXX_G1_STATS_OP_BUSY |
582 				 MV88E6XXX_G1_STATS_OP_READ_CAPTURED | stat);
583 	if (err)
584 		return;
585 
586 	err = mv88e6xxx_g1_stats_wait(chip);
587 	if (err)
588 		return;
589 
590 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_STATS_COUNTER_32, &reg);
591 	if (err)
592 		return;
593 
594 	value = reg << 16;
595 
596 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_STATS_COUNTER_01, &reg);
597 	if (err)
598 		return;
599 
600 	*val = value | reg;
601 }
602 
603 int mv88e6xxx_g1_stats_clear(struct mv88e6xxx_chip *chip)
604 {
605 	int err;
606 	u16 val;
607 
608 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_STATS_OP, &val);
609 	if (err)
610 		return err;
611 
612 	/* Keep the histogram mode bits */
613 	val &= MV88E6XXX_G1_STATS_OP_HIST_RX_TX;
614 	val |= MV88E6XXX_G1_STATS_OP_BUSY | MV88E6XXX_G1_STATS_OP_FLUSH_ALL;
615 
616 	err = mv88e6xxx_g1_write(chip, MV88E6XXX_G1_STATS_OP, val);
617 	if (err)
618 		return err;
619 
620 	/* Wait for the flush to complete. */
621 	return mv88e6xxx_g1_stats_wait(chip);
622 }
623