1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2021 NXP
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
#include <linux/module.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <dt-bindings/phy/phy-imx8-pcie.h>
#define IMX8MM_PCIE_PHY_CMN_REG061 0x184
#define ANA_PLL_CLK_OUT_TO_EXT_IO_EN BIT(0)
#define IMX8MM_PCIE_PHY_CMN_REG062 0x188
#define ANA_PLL_CLK_OUT_TO_EXT_IO_SEL BIT(3)
#define IMX8MM_PCIE_PHY_CMN_REG063 0x18C
#define AUX_PLL_REFCLK_SEL_SYS_PLL GENMASK(7, 6)
#define IMX8MM_PCIE_PHY_CMN_REG064 0x190
#define ANA_AUX_RX_TX_SEL_TX BIT(7)
#define ANA_AUX_RX_TERM_GND_EN BIT(3)
#define ANA_AUX_TX_TERM BIT(2)
#define IMX8MM_PCIE_PHY_CMN_REG065 0x194
#define ANA_AUX_RX_TERM (BIT(7) | BIT(4))
#define ANA_AUX_TX_LVL GENMASK(3, 0)
#define IMX8MM_PCIE_PHY_CMN_REG75 0x1D4
#define PCIE_PHY_CMN_REG75_PLL_DONE 0x3
#define PCIE_PHY_TRSV_REG5 0x414
#define PCIE_PHY_TRSV_REG5_GEN1_DEEMP 0x2D
#define PCIE_PHY_TRSV_REG6 0x418
#define PCIE_PHY_TRSV_REG6_GEN2_DEEMP 0xF
#define IMX8MM_GPR_PCIE_REF_CLK_SEL GENMASK(25, 24)
#define IMX8MM_GPR_PCIE_REF_CLK_PLL FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
#define IMX8MM_GPR_PCIE_REF_CLK_EXT FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x2)
#define IMX8MM_GPR_PCIE_AUX_EN BIT(19)
#define IMX8MM_GPR_PCIE_CMN_RST BIT(18)
#define IMX8MM_GPR_PCIE_POWER_OFF BIT(17)
#define IMX8MM_GPR_PCIE_SSC_EN BIT(16)
#define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE BIT(9)
struct imx8_pcie_phy {
void __iomem *base;
struct clk *clk;
struct phy *phy;
struct regmap *iomuxc_gpr;
struct reset_control *reset;
u32 refclk_pad_mode;
u32 tx_deemph_gen1;
u32 tx_deemph_gen2;
bool clkreq_unused;
};
static int imx8_pcie_phy_init(struct phy *phy)
{
int ret;
u32 val, pad_mode;
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
reset_control_assert(imx8_phy->reset);
pad_mode = imx8_phy->refclk_pad_mode;
/* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
imx8_phy->clkreq_unused ?
0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_AUX_EN,
IMX8MM_GPR_PCIE_AUX_EN);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_POWER_OFF, 0);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_SSC_EN, 0);
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_REF_CLK_SEL,
pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
IMX8MM_GPR_PCIE_REF_CLK_EXT :
IMX8MM_GPR_PCIE_REF_CLK_PLL);
usleep_range(100, 200);
/* Do the PHY common block reset */
regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
IMX8MM_GPR_PCIE_CMN_RST,
IMX8MM_GPR_PCIE_CMN_RST);
usleep_range(200, 500);
if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||
pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {
/* Configure the pad as input */
val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
} else {
/* Configure the PHY to output the refclock via pad */
writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
}
if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT ||
pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {
/* Source clock from SoC internal PLL */
writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
writel(val | ANA_AUX_RX_TERM_GND_EN,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
}
/* Tune PHY de-emphasis setting to pass PCIe compliance. */
if (imx8_phy->tx_deemph_gen1)
writel(imx8_phy->tx_deemph_gen1,
imx8_phy->base + PCIE_PHY_TRSV_REG5);
if (imx8_phy->tx_deemph_gen2)
writel(imx8_phy->tx_deemph_gen2,
imx8_phy->base + PCIE_PHY_TRSV_REG6);
reset_control_deassert(imx8_phy->reset);
/* Polling to check the phy is ready or not. */
ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG75,
val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
10, 20000);
return ret;
}
static int imx8_pcie_phy_power_on(struct phy *phy)
{
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
return clk_prepare_enable(imx8_phy->clk);
}
static int imx8_pcie_phy_power_off(struct phy *phy)
{
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
clk_disable_unprepare(imx8_phy->clk);
return 0;
}
static const struct phy_ops imx8_pcie_phy_ops = {
.init = imx8_pcie_phy_init,
.power_on = imx8_pcie_phy_power_on,
.power_off = imx8_pcie_phy_power_off,
.owner = THIS_MODULE,
};
static int imx8_pcie_phy_probe(struct platform_device *pdev)
{
struct phy_provider *phy_provider;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct imx8_pcie_phy *imx8_phy;
struct resource *res;
imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
if (!imx8_phy)
return -ENOMEM;
/* get PHY refclk pad mode */
of_property_read_u32(np, "fsl,refclk-pad-mode",
&imx8_phy->refclk_pad_mode);
if (of_property_read_u32(np, "fsl,tx-deemph-gen1",
&imx8_phy->tx_deemph_gen1))
imx8_phy->tx_deemph_gen1 = 0;
if (of_property_read_u32(np, "fsl,tx-deemph-gen2",
&imx8_phy->tx_deemph_gen2))
imx8_phy->tx_deemph_gen2 = 0;
if (of_property_read_bool(np, "fsl,clkreq-unsupported"))
imx8_phy->clkreq_unused = true;
else
imx8_phy->clkreq_unused = false;
imx8_phy->clk = devm_clk_get(dev, "ref");
if (IS_ERR(imx8_phy->clk)) {
dev_err(dev, "failed to get imx pcie phy clock\n");
return PTR_ERR(imx8_phy->clk);
}
/* Grab GPR config register range */
imx8_phy->iomuxc_gpr =
syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
if (IS_ERR(imx8_phy->iomuxc_gpr)) {
dev_err(dev, "unable to find iomuxc registers\n");
return PTR_ERR(imx8_phy->iomuxc_gpr);
}
imx8_phy->reset = devm_reset_control_get_exclusive(dev, "pciephy");
if (IS_ERR(imx8_phy->reset)) {
dev_err(dev, "Failed to get PCIEPHY reset control\n");
return PTR_ERR(imx8_phy->reset);
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
imx8_phy->base = devm_ioremap_resource(dev, res);
if (IS_ERR(imx8_phy->base))
return PTR_ERR(imx8_phy->base);
imx8_phy->phy = devm_phy_create(dev, NULL, &imx8_pcie_phy_ops);
if (IS_ERR(imx8_phy->phy))
return PTR_ERR(imx8_phy->phy);
phy_set_drvdata(imx8_phy->phy, imx8_phy);
phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id imx8_pcie_phy_of_match[] = {
{.compatible = "fsl,imx8mm-pcie-phy",},
{ },
};
MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
static struct platform_driver imx8_pcie_phy_driver = {
.probe = imx8_pcie_phy_probe,
.driver = {
.name = "imx8-pcie-phy",
.of_match_table = imx8_pcie_phy_of_match,
}
};
module_platform_driver(imx8_pcie_phy_driver);
MODULE_DESCRIPTION("FSL IMX8 PCIE PHY driver");
MODULE_LICENSE("GPL v2");
|