1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2/*
3 * Northstar Plus switch SerDes/SGMII PHY main logic
4 *
5 * Copyright (C) 2018 Florian Fainelli <f.fainelli@gmail.com>
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/delay.h>
11#include <linux/kernel.h>
12#include <linux/phy.h>
13#include <linux/phylink.h>
14#include <net/dsa.h>
15
16#include "b53_priv.h"
17#include "b53_serdes.h"
18#include "b53_regs.h"
19
20static inline struct b53_pcs *pcs_to_b53_pcs(struct phylink_pcs *pcs)
21{
22	return container_of(pcs, struct b53_pcs, pcs);
23}
24
25static void b53_serdes_write_blk(struct b53_device *dev, u8 offset, u16 block,
26				 u16 value)
27{
28	b53_write16(dev, B53_SERDES_PAGE, B53_SERDES_BLKADDR, block);
29	b53_write16(dev, B53_SERDES_PAGE, offset, value);
30}
31
32static u16 b53_serdes_read_blk(struct b53_device *dev, u8 offset, u16 block)
33{
34	u16 value;
35
36	b53_write16(dev, B53_SERDES_PAGE, B53_SERDES_BLKADDR, block);
37	b53_read16(dev, B53_SERDES_PAGE, offset, &value);
38
39	return value;
40}
41
42static void b53_serdes_set_lane(struct b53_device *dev, u8 lane)
43{
44	if (dev->serdes_lane == lane)
45		return;
46
47	WARN_ON(lane > 1);
48
49	b53_serdes_write_blk(dev, B53_SERDES_LANE,
50			     SERDES_XGXSBLK0_BLOCKADDRESS, lane);
51	dev->serdes_lane = lane;
52}
53
54static void b53_serdes_write(struct b53_device *dev, u8 lane,
55			     u8 offset, u16 block, u16 value)
56{
57	b53_serdes_set_lane(dev, lane);
58	b53_serdes_write_blk(dev, offset, block, value);
59}
60
61static u16 b53_serdes_read(struct b53_device *dev, u8 lane,
62			   u8 offset, u16 block)
63{
64	b53_serdes_set_lane(dev, lane);
65	return b53_serdes_read_blk(dev, offset, block);
66}
67
68static int b53_serdes_config(struct phylink_pcs *pcs, unsigned int neg_mode,
69			     phy_interface_t interface,
70			     const unsigned long *advertising,
71			     bool permit_pause_to_mac)
72{
73	struct b53_device *dev = pcs_to_b53_pcs(pcs)->dev;
74	u8 lane = pcs_to_b53_pcs(pcs)->lane;
75	u16 reg;
76
77	reg = b53_serdes_read(dev, lane, B53_SERDES_DIGITAL_CONTROL(1),
78			      SERDES_DIGITAL_BLK);
79	if (interface == PHY_INTERFACE_MODE_1000BASEX)
80		reg |= FIBER_MODE_1000X;
81	else
82		reg &= ~FIBER_MODE_1000X;
83	b53_serdes_write(dev, lane, B53_SERDES_DIGITAL_CONTROL(1),
84			 SERDES_DIGITAL_BLK, reg);
85
86	return 0;
87}
88
89static void b53_serdes_an_restart(struct phylink_pcs *pcs)
90{
91	struct b53_device *dev = pcs_to_b53_pcs(pcs)->dev;
92	u8 lane = pcs_to_b53_pcs(pcs)->lane;
93	u16 reg;
94
95	reg = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
96			      SERDES_MII_BLK);
97	reg |= BMCR_ANRESTART;
98	b53_serdes_write(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
99			 SERDES_MII_BLK, reg);
100}
101
102static void b53_serdes_get_state(struct phylink_pcs *pcs,
103				  struct phylink_link_state *state)
104{
105	struct b53_device *dev = pcs_to_b53_pcs(pcs)->dev;
106	u8 lane = pcs_to_b53_pcs(pcs)->lane;
107	u16 dig, bmsr;
108
109	dig = b53_serdes_read(dev, lane, B53_SERDES_DIGITAL_STATUS,
110			      SERDES_DIGITAL_BLK);
111	bmsr = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMSR),
112			       SERDES_MII_BLK);
113
114	switch ((dig >> SPEED_STATUS_SHIFT) & SPEED_STATUS_MASK) {
115	case SPEED_STATUS_10:
116		state->speed = SPEED_10;
117		break;
118	case SPEED_STATUS_100:
119		state->speed = SPEED_100;
120		break;
121	case SPEED_STATUS_1000:
122		state->speed = SPEED_1000;
123		break;
124	default:
125	case SPEED_STATUS_2500:
126		state->speed = SPEED_2500;
127		break;
128	}
129
130	state->duplex = dig & DUPLEX_STATUS ? DUPLEX_FULL : DUPLEX_HALF;
131	state->an_complete = !!(bmsr & BMSR_ANEGCOMPLETE);
132	state->link = !!(dig & LINK_STATUS);
133	if (dig & PAUSE_RESOLUTION_RX_SIDE)
134		state->pause |= MLO_PAUSE_RX;
135	if (dig & PAUSE_RESOLUTION_TX_SIDE)
136		state->pause |= MLO_PAUSE_TX;
137}
138
139void b53_serdes_link_set(struct b53_device *dev, int port, unsigned int mode,
140			 phy_interface_t interface, bool link_up)
141{
142	u8 lane = b53_serdes_map_lane(dev, port);
143	u16 reg;
144
145	if (lane == B53_INVALID_LANE)
146		return;
147
148	reg = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
149			      SERDES_MII_BLK);
150	if (link_up)
151		reg &= ~BMCR_PDOWN;
152	else
153		reg |= BMCR_PDOWN;
154	b53_serdes_write(dev, lane, B53_SERDES_MII_REG(MII_BMCR),
155			 SERDES_MII_BLK, reg);
156}
157EXPORT_SYMBOL(b53_serdes_link_set);
158
159static const struct phylink_pcs_ops b53_pcs_ops = {
160	.pcs_get_state = b53_serdes_get_state,
161	.pcs_config = b53_serdes_config,
162	.pcs_an_restart = b53_serdes_an_restart,
163};
164
165void b53_serdes_phylink_get_caps(struct b53_device *dev, int port,
166				 struct phylink_config *config)
167{
168	u8 lane = b53_serdes_map_lane(dev, port);
169
170	if (lane == B53_INVALID_LANE)
171		return;
172
173	switch (lane) {
174	case 0:
175		/* It appears lane 0 supports 2500base-X and 1000base-X */
176		__set_bit(PHY_INTERFACE_MODE_2500BASEX,
177			  config->supported_interfaces);
178		config->mac_capabilities |= MAC_2500FD;
179		fallthrough;
180	case 1:
181		/* It appears lane 1 only supports 1000base-X and SGMII */
182		__set_bit(PHY_INTERFACE_MODE_1000BASEX,
183			  config->supported_interfaces);
184		__set_bit(PHY_INTERFACE_MODE_SGMII,
185			  config->supported_interfaces);
186		config->mac_capabilities |= MAC_1000FD;
187		break;
188	default:
189		break;
190	}
191}
192EXPORT_SYMBOL(b53_serdes_phylink_get_caps);
193
194struct phylink_pcs *b53_serdes_phylink_mac_select_pcs(struct b53_device *dev,
195						      int port,
196						      phy_interface_t interface)
197{
198	u8 lane = b53_serdes_map_lane(dev, port);
199
200	if (lane == B53_INVALID_LANE || lane >= B53_N_PCS ||
201	    !dev->pcs[lane].dev)
202		return NULL;
203
204	if (!phy_interface_mode_is_8023z(interface) &&
205	    interface != PHY_INTERFACE_MODE_SGMII)
206		return NULL;
207
208	return &dev->pcs[lane].pcs;
209}
210EXPORT_SYMBOL(b53_serdes_phylink_mac_select_pcs);
211
212int b53_serdes_init(struct b53_device *dev, int port)
213{
214	u8 lane = b53_serdes_map_lane(dev, port);
215	struct b53_pcs *pcs;
216	u16 id0, msb, lsb;
217
218	if (lane == B53_INVALID_LANE)
219		return -EINVAL;
220
221	id0 = b53_serdes_read(dev, lane, B53_SERDES_ID0, SERDES_ID0);
222	msb = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_PHYSID1),
223			      SERDES_MII_BLK);
224	lsb = b53_serdes_read(dev, lane, B53_SERDES_MII_REG(MII_PHYSID2),
225			      SERDES_MII_BLK);
226	if (id0 == 0 || id0 == 0xffff) {
227		dev_err(dev->dev, "SerDes not initialized, check settings\n");
228		return -ENODEV;
229	}
230
231	dev_info(dev->dev,
232		 "SerDes lane %d, model: %d, rev %c%d (OUI: 0x%08x)\n",
233		 lane, id0 & SERDES_ID0_MODEL_MASK,
234		 (id0 >> SERDES_ID0_REV_LETTER_SHIFT) + 0x41,
235		 (id0 >> SERDES_ID0_REV_NUM_SHIFT) & SERDES_ID0_REV_NUM_MASK,
236		 (u32)msb << 16 | lsb);
237
238	pcs = &dev->pcs[lane];
239	pcs->dev = dev;
240	pcs->lane = lane;
241	pcs->pcs.ops = &b53_pcs_ops;
242	pcs->pcs.neg_mode = true;
243
244	return 0;
245}
246EXPORT_SYMBOL(b53_serdes_init);
247
248MODULE_AUTHOR("Florian Fainelli <f.fainelli@gmail.com>");
249MODULE_DESCRIPTION("B53 Switch SerDes driver");
250MODULE_LICENSE("Dual BSD/GPL");
251