xref: /linux/drivers/mmc/host/dw_mmc-hi3798cv200.c (revision 2a6b6c9a226279b4f6668450ddb21ae655558087)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018 HiSilicon Technologies Co., Ltd.
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/mfd/syscon.h>
8 #include <linux/mmc/host.h>
9 #include <linux/module.h>
10 #include <linux/of_address.h>
11 #include <linux/platform_device.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/consumer.h>
15 
16 #include "dw_mmc.h"
17 #include "dw_mmc-pltfm.h"
18 
19 #define ALL_INT_CLR		0x1ffff
20 
21 struct hi3798cv200_priv {
22 	struct clk *sample_clk;
23 	struct clk *drive_clk;
24 };
25 
26 static void dw_mci_hi3798cv200_set_ios(struct dw_mci *host, struct mmc_ios *ios)
27 {
28 	struct hi3798cv200_priv *priv = host->priv;
29 	u32 val;
30 
31 	val = mci_readl(host, UHS_REG);
32 	if (ios->timing == MMC_TIMING_MMC_DDR52 ||
33 	    ios->timing == MMC_TIMING_UHS_DDR50)
34 		val |= SDMMC_UHS_DDR;
35 	else
36 		val &= ~SDMMC_UHS_DDR;
37 	mci_writel(host, UHS_REG, val);
38 
39 	val = mci_readl(host, ENABLE_SHIFT);
40 	if (ios->timing == MMC_TIMING_MMC_DDR52)
41 		val |= SDMMC_ENABLE_PHASE;
42 	else
43 		val &= ~SDMMC_ENABLE_PHASE;
44 	mci_writel(host, ENABLE_SHIFT, val);
45 
46 	val = mci_readl(host, DDR_REG);
47 	if (ios->timing == MMC_TIMING_MMC_HS400)
48 		val |= SDMMC_DDR_HS400;
49 	else
50 		val &= ~SDMMC_DDR_HS400;
51 	mci_writel(host, DDR_REG, val);
52 
53 	if (ios->timing == MMC_TIMING_MMC_HS ||
54 	    ios->timing == MMC_TIMING_LEGACY)
55 		clk_set_phase(priv->drive_clk, 180);
56 	else if (ios->timing == MMC_TIMING_MMC_HS200)
57 		clk_set_phase(priv->drive_clk, 135);
58 }
59 
60 static int dw_mci_hi3798cv200_execute_tuning(struct dw_mci_slot *slot,
61 					     u32 opcode)
62 {
63 	static const int degrees[] = { 0, 45, 90, 135, 180, 225, 270, 315 };
64 	struct dw_mci *host = slot->host;
65 	struct hi3798cv200_priv *priv = host->priv;
66 	int raise_point = -1, fall_point = -1;
67 	int err, prev_err = -1;
68 	int found = 0;
69 	int i;
70 
71 	for (i = 0; i < ARRAY_SIZE(degrees); i++) {
72 		clk_set_phase(priv->sample_clk, degrees[i]);
73 		mci_writel(host, RINTSTS, ALL_INT_CLR);
74 
75 		err = mmc_send_tuning(slot->mmc, opcode, NULL);
76 		if (!err)
77 			found = 1;
78 
79 		if (i > 0) {
80 			if (err && !prev_err)
81 				fall_point = i - 1;
82 			if (!err && prev_err)
83 				raise_point = i;
84 		}
85 
86 		if (raise_point != -1 && fall_point != -1)
87 			goto tuning_out;
88 
89 		prev_err = err;
90 	}
91 
92 tuning_out:
93 	if (found) {
94 		if (raise_point == -1)
95 			raise_point = 0;
96 		if (fall_point == -1)
97 			fall_point = ARRAY_SIZE(degrees) - 1;
98 		if (fall_point < raise_point) {
99 			if ((raise_point + fall_point) >
100 			    (ARRAY_SIZE(degrees) - 1))
101 				i = fall_point / 2;
102 			else
103 				i = (raise_point + ARRAY_SIZE(degrees) - 1) / 2;
104 		} else {
105 			i = (raise_point + fall_point) / 2;
106 		}
107 
108 		clk_set_phase(priv->sample_clk, degrees[i]);
109 		dev_dbg(host->dev, "Tuning clk_sample[%d, %d], set[%d]\n",
110 			raise_point, fall_point, degrees[i]);
111 	} else {
112 		dev_err(host->dev, "No valid clk_sample shift! use default\n");
113 		err = -EINVAL;
114 	}
115 
116 	mci_writel(host, RINTSTS, ALL_INT_CLR);
117 	return err;
118 }
119 
120 static int dw_mci_hi3798cv200_init(struct dw_mci *host)
121 {
122 	struct hi3798cv200_priv *priv;
123 	int ret;
124 
125 	priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
126 	if (!priv)
127 		return -ENOMEM;
128 
129 	priv->sample_clk = devm_clk_get(host->dev, "ciu-sample");
130 	if (IS_ERR(priv->sample_clk)) {
131 		dev_err(host->dev, "failed to get ciu-sample clock\n");
132 		return PTR_ERR(priv->sample_clk);
133 	}
134 
135 	priv->drive_clk = devm_clk_get(host->dev, "ciu-drive");
136 	if (IS_ERR(priv->drive_clk)) {
137 		dev_err(host->dev, "failed to get ciu-drive clock\n");
138 		return PTR_ERR(priv->drive_clk);
139 	}
140 
141 	ret = clk_prepare_enable(priv->sample_clk);
142 	if (ret) {
143 		dev_err(host->dev, "failed to enable ciu-sample clock\n");
144 		return ret;
145 	}
146 
147 	ret = clk_prepare_enable(priv->drive_clk);
148 	if (ret) {
149 		dev_err(host->dev, "failed to enable ciu-drive clock\n");
150 		goto disable_sample_clk;
151 	}
152 
153 	host->priv = priv;
154 	return 0;
155 
156 disable_sample_clk:
157 	clk_disable_unprepare(priv->sample_clk);
158 	return ret;
159 }
160 
161 static const struct dw_mci_drv_data hi3798cv200_data = {
162 	.common_caps = MMC_CAP_CMD23,
163 	.init = dw_mci_hi3798cv200_init,
164 	.set_ios = dw_mci_hi3798cv200_set_ios,
165 	.execute_tuning = dw_mci_hi3798cv200_execute_tuning,
166 };
167 
168 static int dw_mci_hi3798cv200_probe(struct platform_device *pdev)
169 {
170 	return dw_mci_pltfm_register(pdev, &hi3798cv200_data);
171 }
172 
173 static void dw_mci_hi3798cv200_remove(struct platform_device *pdev)
174 {
175 	struct dw_mci *host = platform_get_drvdata(pdev);
176 	struct hi3798cv200_priv *priv = host->priv;
177 
178 	clk_disable_unprepare(priv->drive_clk);
179 	clk_disable_unprepare(priv->sample_clk);
180 
181 	dw_mci_pltfm_remove(pdev);
182 }
183 
184 static const struct of_device_id dw_mci_hi3798cv200_match[] = {
185 	{ .compatible = "hisilicon,hi3798cv200-dw-mshc", },
186 	{},
187 };
188 
189 MODULE_DEVICE_TABLE(of, dw_mci_hi3798cv200_match);
190 static struct platform_driver dw_mci_hi3798cv200_driver = {
191 	.probe = dw_mci_hi3798cv200_probe,
192 	.remove_new = dw_mci_hi3798cv200_remove,
193 	.driver = {
194 		.name = "dwmmc_hi3798cv200",
195 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
196 		.of_match_table = dw_mci_hi3798cv200_match,
197 	},
198 };
199 module_platform_driver(dw_mci_hi3798cv200_driver);
200 
201 MODULE_DESCRIPTION("HiSilicon Hi3798CV200 Specific DW-MSHC Driver Extension");
202 MODULE_LICENSE("GPL v2");
203