xref: /openbmc/linux/drivers/net/pcs/pcs-xpcs-nxp.c (revision e481ff3f)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright 2021 NXP Semiconductors
3  */
4 #include <linux/pcs/pcs-xpcs.h>
5 #include "pcs-xpcs.h"
6 
7 /* LANE_DRIVER1_0 register */
8 #define SJA1110_LANE_DRIVER1_0		0x8038
9 #define SJA1110_TXDRV(x)		(((x) << 12) & GENMASK(14, 12))
10 
11 /* LANE_DRIVER2_0 register */
12 #define SJA1110_LANE_DRIVER2_0		0x803a
13 #define SJA1110_TXDRVTRIM_LSB(x)	((x) & GENMASK_ULL(15, 0))
14 
15 /* LANE_DRIVER2_1 register */
16 #define SJA1110_LANE_DRIVER2_1		0x803b
17 #define SJA1110_LANE_DRIVER2_1_RSV	BIT(9)
18 #define SJA1110_TXDRVTRIM_MSB(x)	(((x) & GENMASK_ULL(23, 16)) >> 16)
19 
20 /* LANE_TRIM register */
21 #define SJA1110_LANE_TRIM		0x8040
22 #define SJA1110_TXTEN			BIT(11)
23 #define SJA1110_TXRTRIM(x)		(((x) << 8) & GENMASK(10, 8))
24 #define SJA1110_TXPLL_BWSEL		BIT(7)
25 #define SJA1110_RXTEN			BIT(6)
26 #define SJA1110_RXRTRIM(x)		(((x) << 3) & GENMASK(5, 3))
27 #define SJA1110_CDR_GAIN		BIT(2)
28 #define SJA1110_ACCOUPLE_RXVCM_EN	BIT(0)
29 
30 /* LANE_DATAPATH_1 register */
31 #define SJA1110_LANE_DATAPATH_1		0x8037
32 
33 /* POWERDOWN_ENABLE register */
34 #define SJA1110_POWERDOWN_ENABLE	0x8041
35 #define SJA1110_TXPLL_PD		BIT(12)
36 #define SJA1110_TXPD			BIT(11)
37 #define SJA1110_RXPKDETEN		BIT(10)
38 #define SJA1110_RXCH_PD			BIT(9)
39 #define SJA1110_RXBIAS_PD		BIT(8)
40 #define SJA1110_RESET_SER_EN		BIT(7)
41 #define SJA1110_RESET_SER		BIT(6)
42 #define SJA1110_RESET_DES		BIT(5)
43 #define SJA1110_RCVEN			BIT(4)
44 
45 /* RXPLL_CTRL0 register */
46 #define SJA1110_RXPLL_CTRL0		0x8065
47 #define SJA1110_RXPLL_FBDIV(x)		(((x) << 2) & GENMASK(9, 2))
48 
49 /* RXPLL_CTRL1 register */
50 #define SJA1110_RXPLL_CTRL1		0x8066
51 #define SJA1110_RXPLL_REFDIV(x)		((x) & GENMASK(4, 0))
52 
53 /* TXPLL_CTRL0 register */
54 #define SJA1110_TXPLL_CTRL0		0x806d
55 #define SJA1110_TXPLL_FBDIV(x)		((x) & GENMASK(11, 0))
56 
57 /* TXPLL_CTRL1 register */
58 #define SJA1110_TXPLL_CTRL1		0x806e
59 #define SJA1110_TXPLL_REFDIV(x)		((x) & GENMASK(5, 0))
60 
61 /* RX_DATA_DETECT register */
62 #define SJA1110_RX_DATA_DETECT		0x8045
63 
64 /* RX_CDR_CTLE register */
65 #define SJA1110_RX_CDR_CTLE		0x8042
66 
67 /* In NXP SJA1105, the PCS is integrated with a PMA that has the TX lane
68  * polarity inverted by default (PLUS is MINUS, MINUS is PLUS). To obtain
69  * normal non-inverted behavior, the TX lane polarity must be inverted in the
70  * PCS, via the DIGITAL_CONTROL_2 register.
71  */
72 int nxp_sja1105_sgmii_pma_config(struct dw_xpcs *xpcs)
73 {
74 	return xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_DIG_CTRL2,
75 			  DW_VR_MII_DIG_CTRL2_TX_POL_INV);
76 }
77 
78 static int nxp_sja1110_pma_config(struct dw_xpcs *xpcs,
79 				  u16 txpll_fbdiv, u16 txpll_refdiv,
80 				  u16 rxpll_fbdiv, u16 rxpll_refdiv,
81 				  u16 rx_cdr_ctle)
82 {
83 	u16 val;
84 	int ret;
85 
86 	/* Program TX PLL feedback divider and reference divider settings for
87 	 * correct oscillation frequency.
88 	 */
89 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_TXPLL_CTRL0,
90 			 SJA1110_TXPLL_FBDIV(txpll_fbdiv));
91 	if (ret < 0)
92 		return ret;
93 
94 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_TXPLL_CTRL1,
95 			 SJA1110_TXPLL_REFDIV(txpll_refdiv));
96 	if (ret < 0)
97 		return ret;
98 
99 	/* Program transmitter amplitude and disable amplitude trimming */
100 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_LANE_DRIVER1_0,
101 			 SJA1110_TXDRV(0x5));
102 	if (ret < 0)
103 		return ret;
104 
105 	val = SJA1110_TXDRVTRIM_LSB(0xffffffull);
106 
107 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_LANE_DRIVER2_0, val);
108 	if (ret < 0)
109 		return ret;
110 
111 	val = SJA1110_TXDRVTRIM_MSB(0xffffffull) | SJA1110_LANE_DRIVER2_1_RSV;
112 
113 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_LANE_DRIVER2_1, val);
114 	if (ret < 0)
115 		return ret;
116 
117 	/* Enable input and output resistor terminations for low BER. */
118 	val = SJA1110_ACCOUPLE_RXVCM_EN | SJA1110_CDR_GAIN |
119 	      SJA1110_RXRTRIM(4) | SJA1110_RXTEN | SJA1110_TXPLL_BWSEL |
120 	      SJA1110_TXRTRIM(3) | SJA1110_TXTEN;
121 
122 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_LANE_TRIM, val);
123 	if (ret < 0)
124 		return ret;
125 
126 	/* Select PCS as transmitter data source. */
127 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_LANE_DATAPATH_1, 0);
128 	if (ret < 0)
129 		return ret;
130 
131 	/* Program RX PLL feedback divider and reference divider for correct
132 	 * oscillation frequency.
133 	 */
134 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_RXPLL_CTRL0,
135 			 SJA1110_RXPLL_FBDIV(rxpll_fbdiv));
136 	if (ret < 0)
137 		return ret;
138 
139 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_RXPLL_CTRL1,
140 			 SJA1110_RXPLL_REFDIV(rxpll_refdiv));
141 	if (ret < 0)
142 		return ret;
143 
144 	/* Program threshold for receiver signal detector.
145 	 * Enable control of RXPLL by receiver signal detector to disable RXPLL
146 	 * when an input signal is not present.
147 	 */
148 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_RX_DATA_DETECT, 0x0005);
149 	if (ret < 0)
150 		return ret;
151 
152 	/* Enable TX and RX PLLs and circuits.
153 	 * Release reset of PMA to enable data flow to/from PCS.
154 	 */
155 	ret = xpcs_read(xpcs, MDIO_MMD_VEND2, SJA1110_POWERDOWN_ENABLE);
156 	if (ret < 0)
157 		return ret;
158 
159 	val = ret & ~(SJA1110_TXPLL_PD | SJA1110_TXPD | SJA1110_RXCH_PD |
160 		      SJA1110_RXBIAS_PD | SJA1110_RESET_SER_EN |
161 		      SJA1110_RESET_SER | SJA1110_RESET_DES);
162 	val |= SJA1110_RXPKDETEN | SJA1110_RCVEN;
163 
164 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_POWERDOWN_ENABLE, val);
165 	if (ret < 0)
166 		return ret;
167 
168 	/* Program continuous-time linear equalizer (CTLE) settings. */
169 	ret = xpcs_write(xpcs, MDIO_MMD_VEND2, SJA1110_RX_CDR_CTLE,
170 			 rx_cdr_ctle);
171 	if (ret < 0)
172 		return ret;
173 
174 	return 0;
175 }
176 
177 int nxp_sja1110_sgmii_pma_config(struct dw_xpcs *xpcs)
178 {
179 	return nxp_sja1110_pma_config(xpcs, 0x19, 0x1, 0x19, 0x1, 0x212a);
180 }
181 
182 int nxp_sja1110_2500basex_pma_config(struct dw_xpcs *xpcs)
183 {
184 	return nxp_sja1110_pma_config(xpcs, 0x7d, 0x2, 0x7d, 0x2, 0x732a);
185 }
186