1 /*
2  * Copyright (c) 2020 DENX Software Engineering GmbH
3  *               Lukasz Majewski <lukma@denx.de>
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 
7 #define LOG_MODULE_NAME dsa
8 
9 #include <zephyr/logging/log.h>
10 LOG_MODULE_REGISTER(LOG_MODULE_NAME, CONFIG_ETHERNET_LOG_LEVEL);
11 
12 #include <zephyr/device.h>
13 #include <zephyr/drivers/gpio.h>
14 #include <zephyr/kernel.h>
15 #include <errno.h>
16 #include <zephyr/sys/util.h>
17 #include <zephyr/net/ethernet.h>
18 #include <zephyr/linker/sections.h>
19 
20 #if defined(CONFIG_DSA_SPI)
21 #include <zephyr/drivers/spi.h>
22 #else
23 #error "No communication bus defined"
24 #endif
25 
26 #if CONFIG_DSA_KSZ8863
27 #define DT_DRV_COMPAT microchip_ksz8863
28 #include "dsa_ksz8863.h"
29 #elif CONFIG_DSA_KSZ8794
30 #define DT_DRV_COMPAT microchip_ksz8794
31 #include "dsa_ksz8794.h"
32 #else
33 #error "Unsupported KSZ chipset"
34 #endif
35 
36 struct ksz8xxx_data {
37 	int iface_init_count;
38 	bool is_init;
39 #if defined(CONFIG_DSA_SPI)
40 	struct spi_dt_spec spi;
41 #endif
42 };
43 
44 #define PRV_DATA(ctx) ((struct ksz8xxx_data *const)(ctx)->prv_data)
45 
dsa_ksz8xxx_write_reg(const struct ksz8xxx_data * pdev,uint16_t reg_addr,uint8_t value)46 static void dsa_ksz8xxx_write_reg(const struct ksz8xxx_data *pdev,
47 				  uint16_t reg_addr, uint8_t value)
48 {
49 #if defined(CONFIG_DSA_SPI)
50 	uint8_t buf[3];
51 
52 	const struct spi_buf tx_buf = {
53 		.buf = buf,
54 		.len = 3
55 	};
56 	const struct spi_buf_set tx = {
57 		.buffers = &tx_buf,
58 		.count = 1
59 	};
60 
61 	buf[0] = KSZ8XXX_SPI_CMD_WR | ((reg_addr >> 7) & 0x1F);
62 	buf[1] = (reg_addr << 1) & 0xFE;
63 	buf[2] = value;
64 
65 	spi_write_dt(&pdev->spi, &tx);
66 #endif
67 }
68 
dsa_ksz8xxx_read_reg(const struct ksz8xxx_data * pdev,uint16_t reg_addr,uint8_t * value)69 static void dsa_ksz8xxx_read_reg(const struct ksz8xxx_data *pdev,
70 				 uint16_t reg_addr, uint8_t *value)
71 {
72 #if defined(CONFIG_DSA_SPI)
73 	uint8_t buf[3];
74 
75 	const struct spi_buf tx_buf = {
76 		.buf = buf,
77 		.len = 3
78 	};
79 	const struct spi_buf_set tx = {
80 		.buffers = &tx_buf,
81 		.count = 1
82 	};
83 	struct spi_buf rx_buf = {
84 		.buf = buf,
85 		.len = 3
86 	};
87 
88 	const struct spi_buf_set rx = {
89 		.buffers = &rx_buf,
90 		.count = 1
91 	};
92 
93 	buf[0] = KSZ8XXX_SPI_CMD_RD | ((reg_addr >> 7) & 0x1F);
94 	buf[1] = (reg_addr << 1) & 0xFE;
95 	buf[2] = 0x0;
96 
97 	if (!spi_transceive_dt(&pdev->spi, &tx, &rx)) {
98 		*value = buf[2];
99 	} else {
100 		LOG_DBG("Failure while reading register 0x%04x", reg_addr);
101 		*value = 0U;
102 	}
103 #endif
104 }
105 
dsa_ksz8xxx_port_link_status(struct ksz8xxx_data * pdev,uint8_t port)106 static bool dsa_ksz8xxx_port_link_status(struct ksz8xxx_data *pdev,
107 					 uint8_t port)
108 {
109 	uint8_t tmp;
110 
111 	if (port < KSZ8XXX_FIRST_PORT || port > KSZ8XXX_LAST_PORT ||
112 		port == KSZ8XXX_CPU_PORT) {
113 		return false;
114 	}
115 
116 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_STAT2_PORTn(port), &tmp);
117 
118 	return tmp & KSZ8XXX_STAT2_LINK_GOOD;
119 }
120 
121 #if !DT_INST_NODE_HAS_PROP(0, reset_gpios)
dsa_ksz8xxx_soft_reset(struct ksz8xxx_data * pdev)122 static void dsa_ksz8xxx_soft_reset(struct ksz8xxx_data *pdev)
123 {
124 	/* reset switch */
125 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_RESET_REG,
126 			      KSZ8XXX_RESET_SET);
127 	k_busy_wait(KSZ8XXX_SOFT_RESET_DURATION);
128 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_RESET_REG, KSZ8XXX_RESET_CLEAR);
129 }
130 #endif
131 
dsa_ksz8xxx_probe(struct ksz8xxx_data * pdev)132 static int dsa_ksz8xxx_probe(struct ksz8xxx_data *pdev)
133 {
134 	uint16_t timeout = 100;
135 	uint8_t val[2], tmp;
136 
137 	/*
138 	 * Wait for SPI of KSZ8794 being fully operational - up to 10 ms
139 	 */
140 	for (timeout = 100, tmp = 0;
141 	     tmp != KSZ8XXX_CHIP_ID0_ID_DEFAULT && timeout > 0; timeout--) {
142 		dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_CHIP_ID0, &tmp);
143 		k_busy_wait(100);
144 	}
145 
146 	if (timeout == 0) {
147 		LOG_ERR("KSZ8794: No SPI communication!");
148 		return -ENODEV;
149 	}
150 
151 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_CHIP_ID0, &val[0]);
152 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_CHIP_ID1, &val[1]);
153 
154 	if (val[0] != KSZ8XXX_CHIP_ID0_ID_DEFAULT ||
155 	    val[1] != KSZ8XXX_CHIP_ID1_ID_DEFAULT) {
156 		LOG_ERR("Chip ID mismatch. "
157 			"Expected %02x%02x but found %02x%02x",
158 			KSZ8XXX_CHIP_ID0_ID_DEFAULT,
159 			KSZ8XXX_CHIP_ID1_ID_DEFAULT,
160 			val[0],
161 			val[1]);
162 		return -ENODEV;
163 	}
164 
165 	LOG_DBG("KSZ8794: ID0: 0x%x ID1: 0x%x timeout: %d", val[1], val[0],
166 		timeout);
167 
168 	return 0;
169 }
170 
dsa_ksz8xxx_write_static_mac_table(struct ksz8xxx_data * pdev,uint16_t entry_addr,uint8_t * p)171 static int dsa_ksz8xxx_write_static_mac_table(struct ksz8xxx_data *pdev,
172 					      uint16_t entry_addr, uint8_t *p)
173 {
174 	/*
175 	 * According to KSZ8794 manual - write to static mac address table
176 	 * requires write to indirect registers:
177 	 * Write register 0x71 (113)
178 	 * ....
179 	 * Write register 0x78 (120)
180 	 *
181 	 * Then:
182 	 * Write to Register 110 with 0x00 (write static table selected)
183 	 * Write to Register 111 with 0x0x (trigger the write operation, to
184 	 * table entry x)
185 	 */
186 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_7, p[7]);
187 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_6, p[6]);
188 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_5, p[5]);
189 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_4, p[4]);
190 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_3, p[3]);
191 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_2, p[2]);
192 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_1, p[1]);
193 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_DATA_0, p[0]);
194 
195 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_CTRL_0, 0x00);
196 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_CTRL_1, entry_addr);
197 
198 	return 0;
199 }
200 
dsa_ksz8xxx_set_static_mac_table(struct ksz8xxx_data * pdev,const uint8_t * mac,uint8_t fw_port,uint16_t entry_idx)201 static int dsa_ksz8xxx_set_static_mac_table(struct ksz8xxx_data *pdev,
202 					    const uint8_t *mac, uint8_t fw_port,
203 					    uint16_t entry_idx)
204 {
205 	/*
206 	 * The data in uint8_t buf[] buffer is stored in the little endian
207 	 * format, as it eases programming proper KSZ8794 registers.
208 	 */
209 	uint8_t buf[8];
210 
211 	buf[7] = 0;
212 	/* Prepare entry for static MAC address table */
213 	buf[5] = mac[0];
214 	buf[4] = mac[1];
215 	buf[3] = mac[2];
216 	buf[2] = mac[3];
217 	buf[1] = mac[4];
218 	buf[0] = mac[5];
219 
220 	buf[6] = fw_port;
221 	buf[6] |= KSZ8XXX_STATIC_MAC_TABLE_VALID;
222 	buf[6] |= KSZ8XXX_STATIC_MAC_TABLE_OVRD;
223 
224 	dsa_ksz8xxx_write_static_mac_table(pdev, entry_idx, buf);
225 
226 	return 0;
227 }
228 
dsa_ksz8xxx_read_static_mac_table(struct ksz8xxx_data * pdev,uint16_t entry_addr,uint8_t * p)229 static int dsa_ksz8xxx_read_static_mac_table(struct ksz8xxx_data *pdev,
230 					      uint16_t entry_addr, uint8_t *p)
231 {
232 	/*
233 	 * According to KSZ8794 manual - read from static mac address table
234 	 * requires reads from indirect registers:
235 	 *
236 	 * Write to Register 110 with 0x10 (read static table selected)
237 	 * Write to Register 111 with 0x0x (trigger the read operation, to
238 	 * table entry x)
239 	 *
240 	 * Then:
241 	 * Write register 0x71 (113)
242 	 * ....
243 	 * Write register 0x78 (120)
244 	 *
245 	 */
246 
247 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_CTRL_0, 0x10);
248 	dsa_ksz8xxx_write_reg(pdev, KSZ8XXX_REG_IND_CTRL_1, entry_addr);
249 
250 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_7, &p[7]);
251 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_6, &p[6]);
252 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_5, &p[5]);
253 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_4, &p[4]);
254 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_3, &p[3]);
255 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_2, &p[2]);
256 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_1, &p[1]);
257 	dsa_ksz8xxx_read_reg(pdev, KSZ8XXX_REG_IND_DATA_0, &p[0]);
258 
259 	return 0;
260 }
261 
262 #if CONFIG_DSA_KSZ8863
dsa_ksz8xxx_switch_setup(const struct ksz8xxx_data * pdev)263 static int dsa_ksz8xxx_switch_setup(const struct ksz8xxx_data *pdev)
264 {
265 	uint8_t tmp, i;
266 
267 	/*
268 	 * Loop through ports - The same setup when tail tagging is enabled or
269 	 * disabled.
270 	 */
271 	for (i = KSZ8XXX_FIRST_PORT; i <= KSZ8XXX_LAST_PORT; i++) {
272 
273 		/* Enable transmission, reception and switch address learning */
274 		dsa_ksz8xxx_read_reg(pdev, KSZ8863_CTRL2_PORTn(i), &tmp);
275 		tmp |= KSZ8863_CTRL2_TRANSMIT_EN;
276 		tmp |= KSZ8863_CTRL2_RECEIVE_EN;
277 		tmp &= ~KSZ8863_CTRL2_LEARNING_DIS;
278 		dsa_ksz8xxx_write_reg(pdev, KSZ8863_CTRL2_PORTn(i), tmp);
279 	}
280 
281 #if defined(CONFIG_DSA_KSZ_TAIL_TAGGING)
282 	/* Enable tail tag feature */
283 	dsa_ksz8xxx_read_reg(pdev, KSZ8863_GLOBAL_CTRL10, &tmp);
284 	tmp |= KSZ8863_GLOBAL_CTRL1_TAIL_TAG_EN;
285 	dsa_ksz8xxx_write_reg(pdev, KSZ8863_GLOBAL_CTRL10, tmp);
286 #else
287 	/* Disable tail tag feature */
288 	dsa_ksz8xxx_read_reg(pdev, KSZ8863_GLOBAL_CTRL1, &tmp);
289 	tmp &= ~KSZ8863_GLOBAL_CTRL1_TAIL_TAG_EN;
290 	dsa_ksz8xxx_write_reg(pdev, KSZ8863_GLOBAL_CTRL1, tmp);
291 #endif
292 
293 	dsa_ksz8xxx_read_reg(pdev, KSZ8863_GLOBAL_CTRL2, &tmp);
294 	tmp &= ~KSZ8863_GLOBAL_CTRL2_LEG_MAX_PKT_SIZ_CHK_ENA;
295 	dsa_ksz8xxx_write_reg(pdev, KSZ8863_GLOBAL_CTRL2, tmp);
296 
297 	return 0;
298 }
299 #endif
300 
301 #if CONFIG_DSA_KSZ8794
dsa_ksz8xxx_switch_setup(struct ksz8xxx_data * pdev)302 static int dsa_ksz8xxx_switch_setup(struct ksz8xxx_data *pdev)
303 {
304 	uint8_t tmp, i;
305 
306 	/*
307 	 * Loop through ports - The same setup when tail tagging is enabled or
308 	 * disabled.
309 	 */
310 	for (i = KSZ8XXX_FIRST_PORT; i <= KSZ8XXX_LAST_PORT; i++) {
311 		/* Enable transmission, reception and switch address learning */
312 		dsa_ksz8xxx_read_reg(pdev, KSZ8794_CTRL2_PORTn(i), &tmp);
313 		tmp |= KSZ8794_CTRL2_TRANSMIT_EN;
314 		tmp |= KSZ8794_CTRL2_RECEIVE_EN;
315 		tmp &= ~KSZ8794_CTRL2_LEARNING_DIS;
316 		dsa_ksz8xxx_write_reg(pdev, KSZ8794_CTRL2_PORTn(i), tmp);
317 	}
318 
319 #if defined(CONFIG_DSA_KSZ_TAIL_TAGGING)
320 	/* Enable tail tag feature */
321 	dsa_ksz8xxx_read_reg(pdev, KSZ8794_GLOBAL_CTRL10, &tmp);
322 	tmp |= KSZ8794_GLOBAL_CTRL10_TAIL_TAG_EN;
323 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_GLOBAL_CTRL10, tmp);
324 #else
325 	/* Disable tail tag feature */
326 	dsa_ksz8xxx_read_reg(pdev, KSZ8794_GLOBAL_CTRL10, &tmp);
327 	tmp &= ~KSZ8794_GLOBAL_CTRL10_TAIL_TAG_EN;
328 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_GLOBAL_CTRL10, tmp);
329 #endif
330 
331 	dsa_ksz8xxx_read_reg(pdev, KSZ8794_PORT4_IF_CTRL6, &tmp);
332 	LOG_DBG("KSZ8794: CONTROL6: 0x%x port4", tmp);
333 
334 	dsa_ksz8xxx_read_reg(pdev, KSZ8794_PORT4_CTRL2, &tmp);
335 	LOG_DBG("KSZ8794: CONTROL2: 0x%x port4", tmp);
336 
337 	dsa_ksz8xxx_read_reg(pdev, KSZ8794_GLOBAL_CTRL2, &tmp);
338 	tmp |= KSZ8794_GLOBAL_CTRL2_LEG_MAX_PKT_SIZ_CHK_DIS;
339 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_GLOBAL_CTRL2, tmp);
340 
341 	return 0;
342 }
343 
344 #if DT_INST_NODE_HAS_PROP(0, workaround)
345 /*
346  * Workaround 0x01
347  * Solution for Short Cable Problems with the KSZ8795 Family
348  *
349  * Title
350  * Solution for Short Cable Problems with the KSZ8795 Family
351  *
352  * https://microchipsupport.force.com/s/article/Solution-for-Short-Cable-
353  * Problems-with-the-KSZ8795-Family
354  *
355  * Problem Description:
356  * 1) The KSZ8795 family parts might be not link when connected through a few
357  *   type of short cable (<3m).
358  * 2) There may be a link-up issue in the capacitor AC coupling mode for port
359  *   to port or board to board cases.
360  *
361  * Answer
362  * Root Cause:
363  * KSZ8795 family switches with integrated Ethernet PHY that has a DSP based
364  * equalizer EQ that can balance the signal received to adapt various cable
365  * length characteristics. The equalizer default settings amplify the signal
366  * coming in to get more accurate readings from low amplitude signals.
367  * When using some type of short cable (for example, CAT-6 cable with low
368  * attenuation to high frequencies signal vs. CAT-5 cable) or board to board
369  * connection, or port to port with capacitor AC coupling connection, the signal
370  * is amplified too much and cause the link-up failed with same boost setting in
371  * the equalizer EQ.
372  *
373  * Solution/Workaround:
374  * Write a DSP control register that is indirect register (0x3c) to optimize the
375  * equalizer EQ to cover above corner cases.
376  *  w 6e a0 //write the indirect register
377  *  w 6f 3c //assign the indirect hidden register address (0x3c)
378  *  w a0 15 //write 0x15 to REG (0x3c) to optimize the EQ. The default is 0x0a.
379  * Based on testing and practical application, this register setting above can
380  * solve the issue for all type of the short cables and the capacitor AC
381  * coupling mode.
382  *
383  * The indirect DSP register (0x3c) is an 8-bit register, the bits describe as
384  * follows,
385  *
386  * Bits Bit Name            Description                   Mode  Default  Setting
387  *								0x0a     0x15
388  * 7-5  Reserved                                          RO    000      000
389  * 4    Cpu_EQ_Done_Cond1   How to judge EQ is finished,
390  *			  there are two ways to judge
391  *			  if EQ is finished, can set
392  *			  either way                      R/W   0        1
393  * 3-1  Cpu_EQ_CP_Points  Control of EQ training is
394  *			  over-boosted or
395  *     [2:0]              under-boosted, that means to
396  *			  compensate signal attenuation
397  *			  more or less.                   R/W   101      010
398  * 0    Cpu_STOP_RUN      after EQ training completed,
399  *					 stop adaptation  R/W   0        1
400  *
401  * Explanation:
402  * The above register change makes equalizer’s compensation range wider, and
403  * therefore cables with various characteristics can be tolerated. Adjust
404  * equalizer EQ training algorithm to cover a few type of short cables issue.
405  * Also is appropriate for the board to board connection and port to port
406  * connection with the capacitor AC coupling mode.
407  *
408  * Basically, it decides how much signal amplitude to compensate accurately
409  * to the different type of short cable’s characteristics. The current default
410  * value in the indirect register (0x3c) can cover all general standard
411  * Ethernet short cables like CAT-5, CAT-5e without any problem.
412  * Based on tests, a more optimized equalizer adjustment value 0x15 is better
413  * for all corner cases of the short cable and short distance connection for
414  * port to port or board to board cases.
415  */
dsa_ksz8794_phy_workaround_0x01(struct ksz8xxx_data * pdev)416 static int dsa_ksz8794_phy_workaround_0x01(struct ksz8xxx_data *pdev)
417 {
418 	uint8_t indirect_type = 0x0a;
419 	uint8_t indirect_addr = 0x3c;
420 	uint8_t indirect_data = 0x15;
421 
422 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_REG_IND_CTRL_0, indirect_type);
423 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_REG_IND_CTRL_1, indirect_addr);
424 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_IND_BYTE, indirect_data);
425 	LOG_INF("apply workarkound 0x01 for short connections on KSZ8794");
426 	return 0;
427 }
428 
429 /*
430  * Workaround 0x02 and 0x4
431  * Solution for Using CAT-5E or CAT-6 Short Cable with a Link Issue for the
432  * KSZ8795 Family
433  *
434  * Title
435  * Solution for Using CAT-5E or CAT-6 Short Cable with a Link Issue for the
436  * KSZ8795 Family
437  * https://microchipsupport.force.com/s/article/Solution-for-Using-CAT-5E-or
438  * -CAT-6-Short-Cable- with-a-Link-Issue-for-the-KSZ8795-Family
439  *
440  * Question
441  * Possible Problem Description:
442  * 1) KSZ8795 family includes KSZ8795CLX, KSZ8775CLX, KSZ8765CLX and KSZ8794CNX.
443  * 2) The KSZ8795 family copper parts may not link well when connected through a
444  * short CAT-5E or CAT-6 cable (about <=30 meter). The failure rate may be about
445  * 2-5%.
446  *
447  * Answer
448  * Root Cause:
449  * Basically, KSZ8795 10/100 Ethernet switch family was designed based on CAT-5
450  * cable. With the application of more type of cables, specially two types
451  * cables of CAT-5E and CAT-6, both cables have wider bandwidth that has
452  * different frequency characteristics than CAT-5 cable. More higher frequency
453  * component of the CAT-5E or CAT-6 will be amplified in the receiving amplifier
454  * and will cause the received signal distortion due to too much high frequency
455  * components receiving signal amplitude and cause the link-up failure with
456  * short cables.
457  *
458  * Solution/Workaround:
459  * 1) dsa_ksz8794_phy_workaround_0x02()
460  *  Based on the root cause above, adjust the receiver low pass filter to reduce
461  *  the high frequency component to keep the receive signal within a reasonable
462  *  range when using CAT-5E and CAT-6 cable.
463  *
464  *  Set the indirect register as follows for the receiver low pass filter.
465  *  Format is w [Register address] [8-bit data]
466  *   w 6e a0 //write the indirect register
467  *   w 6f 4c //write/assign the internal used indirect register address (0x4c)
468  *   w a0 40 //write 0x40 to indirect register (0x4c) to reduce low pass filter
469  *   bandwidth.
470  *
471  * The register 0x4c bits [7:6] for receiver low pass filter bandwidth control.
472  *
473  *  The default value is ‘00’, change to ‘01’.
474  *  Based on testing and practical application, this register setting above can
475  *  solve the link issue if using CAT-5E and CAT-6 short cables.
476  *
477  *  The indirect register (0x4C) is an 8-bit register. The bits [7:6] are
478  *  described in the table below.
479  *
480  *
481  * Bits Bit Name            Description                   Mode  Default  Setting
482  *								 0x00     0x40
483  * 7-6     RX BW control    Low pass filter bandwidth      R/W   00       01
484  *			  00 = 90MHz
485  *			  01 = 62MHz
486  *			  10 = 55MHz
487  *			  11 = 44MHz
488  * 5       Enable           Near-end loopback              R/W   0        0
489  * 4-3     BTRT             Additional reduce              R/W   00       00
490  * 2       SD               Ext register                   R/W   0        0
491  * 1-0     FXD              reference setting 1.7V, 2V,
492  *			  1.4V
493  *							   R/W   00       00
494  *
495  * Solution/Workaround:
496  * 2) dsa_ksz8794_phy_workaround_0x04()
497  *  For the wider bandwidth cables or on-board capacitor AC coupling
498  * application, we recommend adding/setting the indirect register (0x08) from
499  * default 0x0f to 0x00 that means to change register (0x08) bits [5:0] from
500  * 0x0f to 0x00 to reduce equalizer’s (EQ) initial value to 0x00 for more
501  * short cable or on-board capacitors AC coupling application.
502  *
503  *  Set the indirect register as follows for EQ with 0x00 initial value.
504  *  Format is w [Register address] [8-bit data]
505  *   w 6e a0 //write the indirect register
506  *   w 6f 08 //write/assign the internal used indirect register address (0x08)
507  *   w a0 00 //write 0x00 to indirect register (0x08) to make EQ initial value
508  *	     equal to 0x00 for very short cable (For example, 0.1m or less)
509  *	     or connect two ports directly through capacitors for a capacitor
510  *	     AC couple.
511  *
512  * The indirect DSP register (0x08) is an 8-bit register. The bits [5:0] are
513  * described in the table below.
514  *
515  * Bits Bit Name            Description                   Mode  Default  Setting
516  *								0x0f     0x00
517  * 7    Park EQ Enable      Park Equalizer function enable R/W  0        0
518  * 6    Reserved                                             R  0        0
519  * 5-0  Cpu_EQ_Index        Equalizer index control
520  *			  interface                       R/W   001111   000000
521  *			  from 0 to 55, set EQ initial value
522  *  Conclusion:
523  *  Due to CAT-5E and CAT-6 cable having wider bandwidth, more high frequency
524  *  components will pass the low pass filter into the receiving amplifier and
525  *  cause the received signal amplitude to be too high.
526  *  Reducing the receiver low pass filter bandwidth will be the best way to
527  *  reduce the high frequency components to meet CAT-5E and CAT-6 short cable
528  *  link issue and doesn’t affect CAT-5 cable because CAT-5 is not a wider
529  *  bandwidth cable.
530  *
531  *  The DSP register (0X08) bits [5:0] are for EQ initial value. Its current
532  *  default value is 0x0F, which assumes the need to equalize regardless of the
533  *  cable length. This 0x0f initial equalize value in EQ isn’t needed when
534  *  using very short cable or an on-board direct connection like capacitors AC
535  *  coupling mode. As the cable length increases, the device will equalize
536  *  automatic accordingly from 0x00 EQ initial value.
537  *
538  *  So, it is better to set both register (0x4c) to 0x40 and register (0x08) to
539  *  0x00 for compatibility with all Ethernet cable types and Ethernet cable
540  *  lengths.
541  */
542 
dsa_ksz8794_phy_workaround_0x02(struct ksz8xxx_data * pdev)543 static int dsa_ksz8794_phy_workaround_0x02(struct ksz8xxx_data *pdev)
544 {
545 	uint8_t indirect_type = 0x0a;
546 	uint8_t indirect_addr = 0x4c;
547 	uint8_t indirect_data = 0x40;
548 
549 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_REG_IND_CTRL_0, indirect_type);
550 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_REG_IND_CTRL_1, indirect_addr);
551 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_IND_BYTE, indirect_data);
552 	LOG_INF("apply workarkound 0x02 link issue CAT-5E/6 on KSZ8794");
553 	return 0;
554 }
555 
dsa_ksz8794_phy_workaround_0x04(struct ksz8xxx_data * pdev)556 static int dsa_ksz8794_phy_workaround_0x04(struct ksz8xxx_data *pdev)
557 {
558 	uint8_t indirect_type = 0x0a;
559 	uint8_t indirect_addr = 0x08;
560 	uint8_t indirect_data = 0x00;
561 
562 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_REG_IND_CTRL_0, indirect_type);
563 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_REG_IND_CTRL_1, indirect_addr);
564 	dsa_ksz8xxx_write_reg(pdev, KSZ8794_IND_BYTE, indirect_data);
565 	LOG_INF("apply workarkound 0x04 link issue CAT-5E/6 on KSZ8794");
566 	return 0;
567 }
568 
dsa_ksz8794_apply_workarounds(struct ksz8xxx_data * pdev)569 static int dsa_ksz8794_apply_workarounds(struct ksz8xxx_data *pdev)
570 {
571 	int workaround = DT_INST_PROP(0, workaround);
572 
573 	if (workaround & 0x01) {
574 		dsa_ksz8794_phy_workaround_0x01(pdev);
575 	}
576 	if (workaround & 0x02) {
577 		dsa_ksz8794_phy_workaround_0x02(pdev);
578 	}
579 	if (workaround & 0x04) {
580 		dsa_ksz8794_phy_workaround_0x04(pdev);
581 	}
582 	return 0;
583 }
584 #endif
585 
586 #if DT_INST_NODE_HAS_PROP(0, mii_lowspeed_drivestrength)
dsa_ksz8794_set_lowspeed_drivestrength(struct ksz8xxx_data * pdev)587 static int dsa_ksz8794_set_lowspeed_drivestrength(struct ksz8xxx_data *pdev)
588 {
589 	int mii_lowspeed_drivestrength =
590 		DT_INST_PROP(0, mii_lowspeed_drivestrength);
591 
592 	uint8_t tmp, val;
593 	int ret = 0;
594 
595 	switch (mii_lowspeed_drivestrength) {
596 	case 2:
597 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_2MA;
598 		break;
599 	case 4:
600 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_4MA;
601 		break;
602 	case 8:
603 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_8MA;
604 		break;
605 	case 12:
606 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_12MA;
607 		break;
608 	case 16:
609 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_16MA;
610 		break;
611 	case 20:
612 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_20MA;
613 		break;
614 	case 24:
615 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_24MA;
616 		break;
617 	case 28:
618 		val = KSZ8794_GLOBAL_CTRL20_LOWSPEED_28MA;
619 		break;
620 	default:
621 		ret = -1;
622 		LOG_ERR("KSZ8794: unsupported drive strength %dmA",
623 			mii_lowspeed_drivestrength);
624 		break;
625 	}
626 
627 	if (ret == 0) {
628 		/* set Low-Speed Interface Drive Strength for MII and RMMI */
629 		dsa_ksz8xxx_read_reg(pdev, KSZ8794_GLOBAL_CTRL20, &tmp);
630 		tmp &= ~KSZ8794_GLOBAL_CTRL20_LOWSPEED_MASK;
631 		tmp |= val;
632 		dsa_ksz8xxx_write_reg(pdev, KSZ8794_GLOBAL_CTRL20, tmp);
633 		dsa_ksz8xxx_read_reg(pdev, KSZ8794_GLOBAL_CTRL20, &tmp);
634 		LOG_INF("KSZ8794: set drive strength %dmA",
635 			mii_lowspeed_drivestrength);
636 	}
637 	return ret;
638 }
639 #endif
640 #endif
641 
642 #if DT_INST_NODE_HAS_PROP(0, reset_gpios)
dsa_ksz8xxx_gpio_reset(void)643 static int dsa_ksz8xxx_gpio_reset(void)
644 {
645 	struct gpio_dt_spec reset_gpio = GPIO_DT_SPEC_INST_GET(0, reset_gpios);
646 
647 	if (!gpio_is_ready_dt(&reset_gpio)) {
648 		LOG_ERR("Reset GPIO device not ready");
649 		return -ENODEV;
650 	}
651 	gpio_pin_configure_dt(&reset_gpio, GPIO_OUTPUT_ACTIVE);
652 	k_msleep(10);
653 
654 	gpio_pin_set_dt(&reset_gpio, 0);
655 
656 	return 0;
657 }
658 #endif
659 
660 /* Low level initialization code for DSA PHY */
dsa_hw_init(struct ksz8xxx_data * pdev)661 int dsa_hw_init(struct ksz8xxx_data *pdev)
662 {
663 	int rc;
664 
665 	if (pdev->is_init) {
666 		return 0;
667 	}
668 
669 	/* Hard reset */
670 #if DT_INST_NODE_HAS_PROP(0, reset_gpios)
671 	dsa_ksz8xxx_gpio_reset();
672 
673 	/* Time needed for chip to completely power up (100ms) */
674 	k_busy_wait(KSZ8XXX_HARD_RESET_WAIT);
675 #endif
676 
677 #if defined(CONFIG_DSA_SPI)
678 	if (!spi_is_ready_dt(&pdev->spi)) {
679 		LOG_ERR("SPI bus %s is not ready",
680 			pdev->spi.bus->name);
681 		return -ENODEV;
682 	}
683 #endif
684 
685 	/* Probe attached PHY */
686 	rc = dsa_ksz8xxx_probe(pdev);
687 	if (rc < 0) {
688 		return rc;
689 	}
690 
691 #if !DT_INST_NODE_HAS_PROP(0, reset_gpios)
692 	/* Soft reset */
693 	dsa_ksz8xxx_soft_reset(pdev);
694 #endif
695 
696 	/* Setup KSZ8794 */
697 	dsa_ksz8xxx_switch_setup(pdev);
698 
699 #if DT_INST_NODE_HAS_PROP(0, mii_lowspeed_drivestrength)
700 	dsa_ksz8794_set_lowspeed_drivestrength(pdev);
701 #endif
702 
703 #if DT_INST_NODE_HAS_PROP(0, workaround)
704 	/* apply workarounds */
705 	dsa_ksz8794_apply_workarounds(pdev);
706 #endif
707 
708 	pdev->is_init = true;
709 
710 	return 0;
711 }
712 
dsa_delayed_work(struct k_work * item)713 static void dsa_delayed_work(struct k_work *item)
714 {
715 	struct k_work_delayable *dwork = k_work_delayable_from_work(item);
716 	struct dsa_context *context =
717 		CONTAINER_OF(dwork, struct dsa_context, dsa_work);
718 	struct ksz8xxx_data *pdev = PRV_DATA(context);
719 	bool link_state;
720 	uint8_t i;
721 
722 	for (i = KSZ8XXX_FIRST_PORT; i <= KSZ8XXX_LAST_PORT; i++) {
723 		/* Skip Switch <-> CPU Port */
724 		if (i == KSZ8XXX_CPU_PORT) {
725 			continue;
726 		}
727 
728 		link_state = dsa_ksz8xxx_port_link_status(pdev, i);
729 		if (link_state && !context->link_up[i]) {
730 			LOG_INF("DSA port: %d link UP!", i);
731 			net_eth_carrier_on(context->iface_slave[i]);
732 		} else if (!link_state && context->link_up[i]) {
733 			LOG_INF("DSA port: %d link DOWN!", i);
734 			net_eth_carrier_off(context->iface_slave[i]);
735 		}
736 		context->link_up[i] = link_state;
737 	}
738 
739 	k_work_reschedule(&context->dsa_work, DSA_STATUS_PERIOD_MS);
740 }
741 
dsa_port_init(const struct device * dev)742 int dsa_port_init(const struct device *dev)
743 {
744 	struct dsa_context *data = dev->data;
745 	struct ksz8xxx_data *pdev = PRV_DATA(data);
746 
747 	dsa_hw_init(pdev);
748 	return 0;
749 }
750 
751 /* Generic implementation of writing value to DSA register */
dsa_ksz8xxx_sw_write_reg(const struct device * dev,uint16_t reg_addr,uint8_t value)752 static int dsa_ksz8xxx_sw_write_reg(const struct device *dev, uint16_t reg_addr,
753 				    uint8_t value)
754 {
755 	struct dsa_context *data = dev->data;
756 	struct ksz8xxx_data *pdev = PRV_DATA(data);
757 
758 	dsa_ksz8xxx_write_reg(pdev, reg_addr, value);
759 	return 0;
760 }
761 
762 /* Generic implementation of reading value from DSA register */
dsa_ksz8xxx_sw_read_reg(const struct device * dev,uint16_t reg_addr,uint8_t * value)763 static int dsa_ksz8xxx_sw_read_reg(const struct device *dev, uint16_t reg_addr,
764 				   uint8_t *value)
765 {
766 	struct dsa_context *data = dev->data;
767 	struct ksz8xxx_data *pdev = PRV_DATA(data);
768 
769 	dsa_ksz8xxx_read_reg(pdev, reg_addr, value);
770 	return 0;
771 }
772 
773 /**
774  * @brief Set entry to DSA MAC address table
775  *
776  * @param dev DSA device
777  * @param mac The MAC address to be set in the table
778  * @param fw_port Port number to forward packets
779  * @param tbl_entry_idx The index of entry in the table
780  * @param flags Flags to be set in the entry
781  *
782  * @return 0 if ok, < 0 if error
783  */
dsa_ksz8xxx_set_mac_table_entry(const struct device * dev,const uint8_t * mac,uint8_t fw_port,uint16_t tbl_entry_idx,uint16_t flags)784 static int dsa_ksz8xxx_set_mac_table_entry(const struct device *dev,
785 						const uint8_t *mac,
786 						uint8_t fw_port,
787 						uint16_t tbl_entry_idx,
788 						uint16_t flags)
789 {
790 	struct dsa_context *data = dev->data;
791 	struct ksz8xxx_data *pdev = PRV_DATA(data);
792 
793 	if (flags != 0) {
794 		return -EINVAL;
795 	}
796 
797 	dsa_ksz8xxx_set_static_mac_table(pdev, mac, fw_port,
798 						tbl_entry_idx);
799 
800 	return 0;
801 }
802 
803 /**
804  * @brief Get DSA MAC address table entry
805  *
806  * @param dev DSA device
807  * @param buf The buffer for data read from the table
808  * @param tbl_entry_idx The index of entry in the table
809  *
810  * @return 0 if ok, < 0 if error
811  */
dsa_ksz8xxx_get_mac_table_entry(const struct device * dev,uint8_t * buf,uint16_t tbl_entry_idx)812 static int dsa_ksz8xxx_get_mac_table_entry(const struct device *dev,
813 						uint8_t *buf,
814 						uint16_t tbl_entry_idx)
815 {
816 	struct dsa_context *data = dev->data;
817 	struct ksz8xxx_data *pdev = PRV_DATA(data);
818 
819 	dsa_ksz8xxx_read_static_mac_table(pdev, tbl_entry_idx, buf);
820 
821 	return 0;
822 }
823 
824 #if defined(CONFIG_DSA_KSZ_TAIL_TAGGING)
825 #define DSA_KSZ8795_TAIL_TAG_OVRD	BIT(6)
826 #define DSA_KSZ8795_TAIL_TAG_LOOKUP	BIT(7)
827 
828 #define DSA_KSZ8794_EGRESS_TAG_LEN 1
829 #define DSA_KSZ8794_INGRESS_TAG_LEN 1
830 
831 #define DSA_MIN_L2_FRAME_SIZE 64
832 #define DSA_L2_FCS_SIZE 4
833 
dsa_ksz8xxx_xmit_pkt(struct net_if * iface,struct net_pkt * pkt)834 struct net_pkt *dsa_ksz8xxx_xmit_pkt(struct net_if *iface, struct net_pkt *pkt)
835 {
836 	struct ethernet_context *ctx = net_if_l2_data(iface);
837 	struct net_eth_hdr *hdr = NET_ETH_HDR(pkt);
838 	struct net_linkaddr lladst;
839 	uint8_t port_idx, *dbuf;
840 	struct net_buf *buf;
841 	size_t len, pad = 0;
842 
843 	lladst.len = sizeof(hdr->dst.addr);
844 	lladst.addr = &hdr->dst.addr[0];
845 
846 	len = net_pkt_get_len(pkt);
847 	/*
848 	 * For KSZ8794 one needs to 'pad' the L2 frame to its minimal size
849 	 * (64B) before appending TAIL TAG and FCS
850 	 */
851 	if (len < (DSA_MIN_L2_FRAME_SIZE - DSA_L2_FCS_SIZE)) {
852 		/* Calculate number of bytes needed for padding */
853 		pad = DSA_MIN_L2_FRAME_SIZE - DSA_L2_FCS_SIZE - len;
854 	}
855 
856 	buf = net_buf_alloc_len(net_buf_pool_get(pkt->buffer->pool_id),
857 				pad + DSA_KSZ8794_INGRESS_TAG_LEN, K_NO_WAIT);
858 	if (!buf) {
859 		LOG_ERR("DSA cannot allocate new data buffer");
860 		return NULL;
861 	}
862 
863 	/*
864 	 * Get the pointer to struct's net_buf_simple data and zero out the
865 	 * padding and tag byte placeholder
866 	 */
867 	dbuf = net_buf_simple_tail(&(buf->b));
868 	memset(dbuf, 0x0, pad + DSA_KSZ8794_INGRESS_TAG_LEN);
869 
870 	/*
871 	 * For master port (eth0) set the bit 7 to use look-up table to pass
872 	 * packet to correct interface (bits [0..6] _are_ ignored).
873 	 *
874 	 * For slave ports (lan1..3) just set the tag properly:
875 	 * bit 0 -> eth1, bit 1 -> eth2. bit 2 -> eth3
876 	 * It may be also necessary to set bit 6 to "anyhow send packets to
877 	 * specified port in Bits[3:0]". This may be needed for RSTP
878 	 * implementation (when the switch port is disabled, but shall handle
879 	 * LLDP packets).
880 	 */
881 	if (dsa_is_port_master(iface)) {
882 		port_idx = DSA_KSZ8795_TAIL_TAG_LOOKUP;
883 	} else {
884 		port_idx = (1 << (ctx->dsa_port_idx));
885 	}
886 
887 	NET_DBG("TT - port: 0x%x[%p] LEN: %d 0x%x 0x%x 0x%x 0x%x 0x%x 0x%x",
888 		port_idx, iface, len, lladst.addr[0], lladst.addr[1],
889 		lladst.addr[2], lladst.addr[3], lladst.addr[4], lladst.addr[5]);
890 
891 	/* The tail tag shall be placed after the padding (if present) */
892 	dbuf[pad] = port_idx;
893 
894 	/* Set proper len member for the actual struct net_buf_simple */
895 	net_buf_add(buf, pad + DSA_KSZ8794_INGRESS_TAG_LEN);
896 
897 	/* Append struct net_buf to packet data */
898 	net_buf_frag_add(pkt->buffer, buf);
899 
900 	return pkt;
901 }
902 
903 /**
904  * @brief DSA function to get proper interface
905  *
906  * This is the function for assigning proper slave interface after receiving
907  * the packet on master.
908  *
909  * @param iface Network interface
910  * @param pkt Network packet
911  *
912  * Returns:
913  *  - Pointer to struct net_if
914  */
dsa_ksz8xxx_get_iface(struct net_if * iface,struct net_pkt * pkt)915 static struct net_if *dsa_ksz8xxx_get_iface(struct net_if *iface,
916 					    struct net_pkt *pkt)
917 {
918 	struct ethernet_context *ctx;
919 	struct net_if *iface_sw;
920 	size_t plen;
921 	uint8_t pnum;
922 
923 	if (!(net_eth_get_hw_capabilities(iface) &
924 	      (ETHERNET_DSA_SLAVE_PORT | ETHERNET_DSA_MASTER_PORT))) {
925 		return iface;
926 	}
927 
928 	net_pkt_set_overwrite(pkt, true);
929 	net_pkt_cursor_init(pkt);
930 	plen = net_pkt_get_len(pkt);
931 
932 	net_pkt_skip(pkt, plen - DSA_KSZ8794_EGRESS_TAG_LEN);
933 	net_pkt_read_u8(pkt, &pnum);
934 
935 	net_pkt_update_length(pkt, plen - DSA_KSZ8794_EGRESS_TAG_LEN);
936 
937 	/*
938 	 * NOTE:
939 	 * The below approach is only for ip_k66f board as we do know
940 	 * that eth0 is on position (index) 1, then we do have lan1 with
941 	 * index 2, lan2 with 3 and lan3 with 4.
942 	 *
943 	 * This is caused by eth interfaces placing order by linker and
944 	 * may vary on other boards, where are for example two eth
945 	 * interfaces available.
946 	 */
947 	iface_sw = net_if_get_by_index(pnum + 2);
948 
949 	ctx = net_if_l2_data(iface);
950 	NET_DBG("TT - plen: %d pnum: %d pos: 0x%p dsa_port_idx: %d",
951 		plen - DSA_KSZ8794_EGRESS_TAG_LEN, pnum,
952 		net_pkt_cursor_get_pos(pkt), ctx->dsa_port_idx);
953 
954 	return iface_sw;
955 }
956 #endif
957 
dsa_iface_init(struct net_if * iface)958 static void dsa_iface_init(struct net_if *iface)
959 {
960 	struct dsa_slave_config *cfg = (struct dsa_slave_config *)
961 		net_if_get_device(iface)->config;
962 	struct ethernet_context *ctx = net_if_l2_data(iface);
963 	const struct device *dm, *dev = net_if_get_device(iface);
964 	struct dsa_context *context = dev->data;
965 	struct ksz8xxx_data *pdev = PRV_DATA(context);
966 	struct ethernet_context *ctx_master;
967 	int i = pdev->iface_init_count;
968 
969 	/* Find master port for ksz8794 switch */
970 	if (context->iface_master == NULL) {
971 		dm = DEVICE_DT_GET(DT_INST_PHANDLE(0, dsa_master_port));
972 		context->iface_master = net_if_lookup_by_dev(dm);
973 		if (context->iface_master == NULL) {
974 			LOG_ERR("DSA: Master iface NOT found!");
975 			return;
976 		}
977 
978 		/*
979 		 * Provide pointer to DSA context to master's eth interface
980 		 * struct ethernet_context
981 		 */
982 		ctx_master = net_if_l2_data(context->iface_master);
983 		ctx_master->dsa_ctx = context;
984 	}
985 
986 	if (context->iface_slave[i] == NULL) {
987 		context->iface_slave[i] = iface;
988 		net_if_set_link_addr(iface, cfg->mac_addr,
989 				     sizeof(cfg->mac_addr),
990 				     NET_LINK_ETHERNET);
991 		ctx->dsa_port_idx = i;
992 		ctx->dsa_ctx = context;
993 
994 		/*
995 		 * Initialize ethernet context 'work' for this iface to
996 		 * be able to monitor the carrier status.
997 		 */
998 		ethernet_init(iface);
999 	}
1000 
1001 	pdev->iface_init_count++;
1002 	net_if_carrier_off(iface);
1003 
1004 	/*
1005 	 * Start DSA work to monitor status of ports (read from switch IC)
1006 	 * only when carrier_work is properly initialized for all slave
1007 	 * interfaces.
1008 	 */
1009 	if (pdev->iface_init_count == context->num_slave_ports) {
1010 		k_work_init_delayable(&context->dsa_work, dsa_delayed_work);
1011 		k_work_reschedule(&context->dsa_work, DSA_STATUS_PERIOD_MS);
1012 	}
1013 }
1014 
dsa_port_get_capabilities(const struct device * dev)1015 static enum ethernet_hw_caps dsa_port_get_capabilities(const struct device *dev)
1016 {
1017 	ARG_UNUSED(dev);
1018 
1019 	return ETHERNET_DSA_SLAVE_PORT | ETHERNET_LINK_10BASE_T |
1020 		ETHERNET_LINK_100BASE_T;
1021 }
1022 
1023 const struct ethernet_api dsa_eth_api_funcs = {
1024 	.iface_api.init		= dsa_iface_init,
1025 	.get_capabilities	= dsa_port_get_capabilities,
1026 	.send                   = dsa_tx,
1027 };
1028 
1029 static struct dsa_api dsa_api_f = {
1030 	.switch_read = dsa_ksz8xxx_sw_read_reg,
1031 	.switch_write = dsa_ksz8xxx_sw_write_reg,
1032 	.switch_set_mac_table_entry = dsa_ksz8xxx_set_mac_table_entry,
1033 	.switch_get_mac_table_entry = dsa_ksz8xxx_get_mac_table_entry,
1034 #if defined(CONFIG_DSA_KSZ_TAIL_TAGGING)
1035 	.dsa_xmit_pkt = dsa_ksz8xxx_xmit_pkt,
1036 	.dsa_get_iface = dsa_ksz8xxx_get_iface,
1037 #endif
1038 };
1039 
1040 /*
1041  * The order of NET_DEVICE_INIT_INSTANCE() placement IS important.
1042  *
1043  * To make the code simpler - the special care needs to be put on
1044  * the proper placement of eth0, lan1, lan2, lan3, etc - to avoid
1045  * the need to search for proper interface when each packet is
1046  * received or sent.
1047  * The net_if.c has a very fast API to provide access to linked by
1048  * the linker struct net_if(s) via device or index. As it is already
1049  * available for use - let's use it.
1050  *
1051  * To do that one needs to check how linker places the interfaces.
1052  * To inspect:
1053  * objdump -dst ./zephyr/CMakeFiles/zephyr.dir/drivers/ethernet/eth_mcux.c.obj\
1054  * | grep "__net_if"
1055  * (The real problem is with eth0 and lanX order)
1056  *
1057  * If this approach is not enough for a simple system (like e.g. ip_k66f, one
1058  * can prepare dedicated linker script for the board to force the
1059  * order for complicated designs (like ones with eth0, eth1, and lanX).
1060  *
1061  * For simple cases it is just good enough.
1062  */
1063 
1064 #define NET_SLAVE_DEVICE_INIT_INSTANCE(slave, n)                           \
1065 	const struct dsa_slave_config dsa_0_slave_##slave##_config = {     \
1066 		.mac_addr = DT_PROP_OR(slave, local_mac_address, {0})      \
1067 	};                                                                 \
1068 	NET_DEVICE_DT_DEFINE_INSTANCE(slave,                               \
1069 	n,                                                                 \
1070 	dsa_port_init,                                                     \
1071 	NULL,                                                              \
1072 	&dsa_context_##n,                                                  \
1073 	&dsa_0_slave_##slave##_config,                                     \
1074 	CONFIG_ETH_INIT_PRIORITY,                                          \
1075 	&dsa_eth_api_funcs,                                                \
1076 	ETHERNET_L2,                                                       \
1077 	NET_L2_GET_CTX_TYPE(ETHERNET_L2),                                  \
1078 	NET_ETH_MTU);
1079 
1080 #define NET_SLAVE_DEVICE_0_INIT_INSTANCE(slave)				\
1081 		NET_SLAVE_DEVICE_INIT_INSTANCE(slave, 0)
1082 #define NET_SLAVE_DEVICE_1_INIT_INSTANCE(slave)				\
1083 		NET_SLAVE_DEVICE_INIT_INSTANCE(slave, 1)
1084 #define NET_SLAVE_DEVICE_2_INIT_INSTANCE(slave)				\
1085 		NET_SLAVE_DEVICE_INIT_INSTANCE(slave, 2)
1086 #define NET_SLAVE_DEVICE_3_INIT_INSTANCE(slave)				\
1087 		NET_SLAVE_DEVICE_INIT_INSTANCE(slave, 3)
1088 #define NET_SLAVE_DEVICE_4_INIT_INSTANCE(slave)				\
1089 		NET_SLAVE_DEVICE_INIT_INSTANCE(slave, 4)
1090 
1091 #if defined(CONFIG_DSA_SPI)
1092 #define DSA_SPI_BUS_CONFIGURATION(n)					\
1093 	.spi = SPI_DT_SPEC_INST_GET(n,					\
1094 			SPI_WORD_SET(8),				\
1095 			0U)
1096 #else
1097 #define DSA_SPI_BUS_CONFIGURATION(n)
1098 #endif
1099 
1100 #define DSA_DEVICE(n)							\
1101 	static struct ksz8xxx_data dsa_device_prv_data_##n = {		\
1102 		.iface_init_count = 0,					\
1103 		.is_init = false,					\
1104 		DSA_SPI_BUS_CONFIGURATION(n),				\
1105 	};								\
1106 	static struct dsa_context dsa_context_##n = {			\
1107 		.num_slave_ports = DT_INST_PROP(0, dsa_slave_ports),	\
1108 		.dapi = &dsa_api_f,					\
1109 		.prv_data = (void *)&dsa_device_prv_data_##n,		\
1110 	};								\
1111 	DT_INST_FOREACH_CHILD_VARGS(n, NET_SLAVE_DEVICE_INIT_INSTANCE, n);
1112 
1113 
1114 DT_INST_FOREACH_STATUS_OKAY(DSA_DEVICE);
1115