1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
3  */
4 
5 /* Qualcomm Technologies, Inc. QDF2432 EMAC SGMII Controller driver.
6  */
7 
8 #include <linux/iopoll.h>
9 #include "emac.h"
10 
11 /* EMAC_SGMII register offsets */
12 #define EMAC_SGMII_PHY_TX_PWR_CTRL		0x000C
13 #define EMAC_SGMII_PHY_LANE_CTRL1		0x0018
14 #define EMAC_SGMII_PHY_CDR_CTRL0		0x0058
15 #define EMAC_SGMII_PHY_POW_DWN_CTRL0		0x0080
16 #define EMAC_SGMII_PHY_RESET_CTRL		0x00a8
17 #define EMAC_SGMII_PHY_INTERRUPT_MASK		0x00b4
18 
19 /* SGMII digital lane registers */
20 #define EMAC_SGMII_LN_DRVR_CTRL0		0x000C
21 #define EMAC_SGMII_LN_DRVR_TAP_EN		0x0018
22 #define EMAC_SGMII_LN_TX_MARGINING		0x001C
23 #define EMAC_SGMII_LN_TX_PRE			0x0020
24 #define EMAC_SGMII_LN_TX_POST			0x0024
25 #define EMAC_SGMII_LN_TX_BAND_MODE		0x0060
26 #define EMAC_SGMII_LN_LANE_MODE			0x0064
27 #define EMAC_SGMII_LN_PARALLEL_RATE		0x0078
28 #define EMAC_SGMII_LN_CML_CTRL_MODE0		0x00B8
29 #define EMAC_SGMII_LN_MIXER_CTRL_MODE0		0x00D0
30 #define EMAC_SGMII_LN_VGA_INITVAL		0x0134
31 #define EMAC_SGMII_LN_UCDR_FO_GAIN_MODE0	0x017C
32 #define EMAC_SGMII_LN_UCDR_SO_GAIN_MODE0	0x0188
33 #define EMAC_SGMII_LN_UCDR_SO_CONFIG		0x0194
34 #define EMAC_SGMII_LN_RX_BAND			0x019C
35 #define EMAC_SGMII_LN_RX_RCVR_PATH1_MODE0	0x01B8
36 #define EMAC_SGMII_LN_RSM_CONFIG		0x01F0
37 #define EMAC_SGMII_LN_SIGDET_ENABLES		0x0224
38 #define EMAC_SGMII_LN_SIGDET_CNTRL		0x0228
39 #define EMAC_SGMII_LN_SIGDET_DEGLITCH_CNTRL	0x022C
40 #define EMAC_SGMII_LN_RX_EN_SIGNAL		0x02A0
41 #define EMAC_SGMII_LN_RX_MISC_CNTRL0		0x02AC
42 #define EMAC_SGMII_LN_DRVR_LOGIC_CLKDIV		0x02BC
43 
44 /* SGMII digital lane register values */
45 #define UCDR_STEP_BY_TWO_MODE0			BIT(7)
46 #define UCDR_xO_GAIN_MODE(x)			((x) & 0x7f)
47 #define UCDR_ENABLE				BIT(6)
48 #define UCDR_SO_SATURATION(x)			((x) & 0x3f)
49 
50 #define SIGDET_LP_BYP_PS4			BIT(7)
51 #define SIGDET_EN_PS0_TO_PS2			BIT(6)
52 
53 #define TXVAL_VALID_INIT			BIT(4)
54 #define KR_PCIGEN3_MODE				BIT(0)
55 
56 #define MAIN_EN					BIT(0)
57 
58 #define TX_MARGINING_MUX			BIT(6)
59 #define TX_MARGINING(x)				((x) & 0x3f)
60 
61 #define TX_PRE_MUX				BIT(6)
62 
63 #define TX_POST_MUX				BIT(6)
64 
65 #define CML_GEAR_MODE(x)			(((x) & 7) << 3)
66 #define CML2CMOS_IBOOST_MODE(x)			((x) & 7)
67 
68 #define MIXER_LOADB_MODE(x)			(((x) & 0xf) << 2)
69 #define MIXER_DATARATE_MODE(x)			((x) & 3)
70 
71 #define VGA_THRESH_DFE(x)			((x) & 0x3f)
72 
73 #define SIGDET_LP_BYP_PS0_TO_PS2		BIT(5)
74 #define SIGDET_FLT_BYP				BIT(0)
75 
76 #define SIGDET_LVL(x)				(((x) & 0xf) << 4)
77 
78 #define SIGDET_DEGLITCH_CTRL(x)			(((x) & 0xf) << 1)
79 
80 #define DRVR_LOGIC_CLK_EN			BIT(4)
81 #define DRVR_LOGIC_CLK_DIV(x)			((x) & 0xf)
82 
83 #define PARALLEL_RATE_MODE0(x)			((x) & 0x3)
84 
85 #define BAND_MODE0(x)				((x) & 0x3)
86 
87 #define LANE_MODE(x)				((x) & 0x1f)
88 
89 #define CDR_PD_SEL_MODE0(x)			(((x) & 0x3) << 5)
90 #define BYPASS_RSM_SAMP_CAL			BIT(1)
91 #define BYPASS_RSM_DLL_CAL			BIT(0)
92 
93 #define L0_RX_EQUALIZE_ENABLE			BIT(6)
94 
95 #define PWRDN_B					BIT(0)
96 
97 #define CDR_MAX_CNT(x)				((x) & 0xff)
98 
99 #define SERDES_START_WAIT_TIMES			100
100 
101 struct emac_reg_write {
102 	unsigned int offset;
103 	u32 val;
104 };
105 
emac_reg_write_all(void __iomem * base,const struct emac_reg_write * itr,size_t size)106 static void emac_reg_write_all(void __iomem *base,
107 			       const struct emac_reg_write *itr, size_t size)
108 {
109 	size_t i;
110 
111 	for (i = 0; i < size; ++itr, ++i)
112 		writel(itr->val, base + itr->offset);
113 }
114 
115 static const struct emac_reg_write sgmii_laned[] = {
116 	/* CDR Settings */
117 	{EMAC_SGMII_LN_UCDR_FO_GAIN_MODE0,
118 		UCDR_STEP_BY_TWO_MODE0 | UCDR_xO_GAIN_MODE(10)},
119 	{EMAC_SGMII_LN_UCDR_SO_GAIN_MODE0, UCDR_xO_GAIN_MODE(0)},
120 	{EMAC_SGMII_LN_UCDR_SO_CONFIG, UCDR_ENABLE | UCDR_SO_SATURATION(12)},
121 
122 	/* TX/RX Settings */
123 	{EMAC_SGMII_LN_RX_EN_SIGNAL, SIGDET_LP_BYP_PS4 | SIGDET_EN_PS0_TO_PS2},
124 
125 	{EMAC_SGMII_LN_DRVR_CTRL0, TXVAL_VALID_INIT | KR_PCIGEN3_MODE},
126 	{EMAC_SGMII_LN_DRVR_TAP_EN, MAIN_EN},
127 	{EMAC_SGMII_LN_TX_MARGINING, TX_MARGINING_MUX | TX_MARGINING(25)},
128 	{EMAC_SGMII_LN_TX_PRE, TX_PRE_MUX},
129 	{EMAC_SGMII_LN_TX_POST, TX_POST_MUX},
130 
131 	{EMAC_SGMII_LN_CML_CTRL_MODE0,
132 		CML_GEAR_MODE(1) | CML2CMOS_IBOOST_MODE(1)},
133 	{EMAC_SGMII_LN_MIXER_CTRL_MODE0,
134 		MIXER_LOADB_MODE(12) | MIXER_DATARATE_MODE(1)},
135 	{EMAC_SGMII_LN_VGA_INITVAL, VGA_THRESH_DFE(31)},
136 	{EMAC_SGMII_LN_SIGDET_ENABLES,
137 		SIGDET_LP_BYP_PS0_TO_PS2 | SIGDET_FLT_BYP},
138 	{EMAC_SGMII_LN_SIGDET_CNTRL, SIGDET_LVL(8)},
139 
140 	{EMAC_SGMII_LN_SIGDET_DEGLITCH_CNTRL, SIGDET_DEGLITCH_CTRL(4)},
141 	{EMAC_SGMII_LN_RX_MISC_CNTRL0, 0},
142 	{EMAC_SGMII_LN_DRVR_LOGIC_CLKDIV,
143 		DRVR_LOGIC_CLK_EN | DRVR_LOGIC_CLK_DIV(4)},
144 
145 	{EMAC_SGMII_LN_PARALLEL_RATE, PARALLEL_RATE_MODE0(1)},
146 	{EMAC_SGMII_LN_TX_BAND_MODE, BAND_MODE0(2)},
147 	{EMAC_SGMII_LN_RX_BAND, BAND_MODE0(3)},
148 	{EMAC_SGMII_LN_LANE_MODE, LANE_MODE(26)},
149 	{EMAC_SGMII_LN_RX_RCVR_PATH1_MODE0, CDR_PD_SEL_MODE0(3)},
150 	{EMAC_SGMII_LN_RSM_CONFIG, BYPASS_RSM_SAMP_CAL | BYPASS_RSM_DLL_CAL},
151 };
152 
153 static const struct emac_reg_write physical_coding_sublayer_programming[] = {
154 	{EMAC_SGMII_PHY_POW_DWN_CTRL0, PWRDN_B},
155 	{EMAC_SGMII_PHY_CDR_CTRL0, CDR_MAX_CNT(15)},
156 	{EMAC_SGMII_PHY_TX_PWR_CTRL, 0},
157 	{EMAC_SGMII_PHY_LANE_CTRL1, L0_RX_EQUALIZE_ENABLE},
158 };
159 
emac_sgmii_init_qdf2432(struct emac_adapter * adpt)160 int emac_sgmii_init_qdf2432(struct emac_adapter *adpt)
161 {
162 	struct emac_sgmii *phy = &adpt->phy;
163 	void __iomem *phy_regs = phy->base;
164 	void __iomem *laned = phy->digital;
165 	unsigned int i;
166 	u32 lnstatus;
167 
168 	/* PCS lane-x init */
169 	emac_reg_write_all(phy->base, physical_coding_sublayer_programming,
170 			   ARRAY_SIZE(physical_coding_sublayer_programming));
171 
172 	/* SGMII lane-x init */
173 	emac_reg_write_all(phy->digital, sgmii_laned, ARRAY_SIZE(sgmii_laned));
174 
175 	/* Power up PCS and start reset lane state machine */
176 
177 	writel(0, phy_regs + EMAC_SGMII_PHY_RESET_CTRL);
178 	writel(1, laned + SGMII_LN_RSM_START);
179 
180 	/* Wait for c_ready assertion */
181 	for (i = 0; i < SERDES_START_WAIT_TIMES; i++) {
182 		lnstatus = readl(phy_regs + SGMII_PHY_LN_LANE_STATUS);
183 		if (lnstatus & BIT(1))
184 			break;
185 		usleep_range(100, 200);
186 	}
187 
188 	if (i == SERDES_START_WAIT_TIMES) {
189 		netdev_err(adpt->netdev, "SGMII failed to start\n");
190 		return -EIO;
191 	}
192 
193 	/* Disable digital and SERDES loopback */
194 	writel(0, phy_regs + SGMII_PHY_LN_BIST_GEN0);
195 	writel(0, phy_regs + SGMII_PHY_LN_BIST_GEN2);
196 	writel(0, phy_regs + SGMII_PHY_LN_CDR_CTRL1);
197 
198 	/* Mask out all the SGMII Interrupt */
199 	writel(0, phy_regs + EMAC_SGMII_PHY_INTERRUPT_MASK);
200 
201 	return 0;
202 }
203