xref: /openbmc/linux/drivers/ata/ahci_imx.c (revision e23feb16)
1 /*
2  * Freescale IMX AHCI SATA platform driver
3  * Copyright 2013 Freescale Semiconductor, Inc.
4  *
5  * based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program. If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/regmap.h>
24 #include <linux/ahci_platform.h>
25 #include <linux/of_device.h>
26 #include <linux/mfd/syscon.h>
27 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
28 #include "ahci.h"
29 
30 enum {
31 	HOST_TIMER1MS = 0xe0, /* Timer 1-ms */
32 };
33 
34 struct imx_ahci_priv {
35 	struct platform_device *ahci_pdev;
36 	struct clk *sata_ref_clk;
37 	struct clk *ahb_clk;
38 	struct regmap *gpr;
39 };
40 
41 static int imx6q_sata_init(struct device *dev, void __iomem *mmio)
42 {
43 	int ret = 0;
44 	unsigned int reg_val;
45 	struct imx_ahci_priv *imxpriv = dev_get_drvdata(dev->parent);
46 
47 	imxpriv->gpr =
48 		syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
49 	if (IS_ERR(imxpriv->gpr)) {
50 		dev_err(dev, "failed to find fsl,imx6q-iomux-gpr regmap\n");
51 		return PTR_ERR(imxpriv->gpr);
52 	}
53 
54 	ret = clk_prepare_enable(imxpriv->sata_ref_clk);
55 	if (ret < 0) {
56 		dev_err(dev, "prepare-enable sata_ref clock err:%d\n", ret);
57 		return ret;
58 	}
59 
60 	/*
61 	 * set PHY Paremeters, two steps to configure the GPR13,
62 	 * one write for rest of parameters, mask of first write
63 	 * is 0x07fffffd, and the other one write for setting
64 	 * the mpll_clk_en.
65 	 */
66 	regmap_update_bits(imxpriv->gpr, 0x34, IMX6Q_GPR13_SATA_RX_EQ_VAL_MASK
67 			| IMX6Q_GPR13_SATA_RX_LOS_LVL_MASK
68 			| IMX6Q_GPR13_SATA_RX_DPLL_MODE_MASK
69 			| IMX6Q_GPR13_SATA_SPD_MODE_MASK
70 			| IMX6Q_GPR13_SATA_MPLL_SS_EN
71 			| IMX6Q_GPR13_SATA_TX_ATTEN_MASK
72 			| IMX6Q_GPR13_SATA_TX_BOOST_MASK
73 			| IMX6Q_GPR13_SATA_TX_LVL_MASK
74 			| IMX6Q_GPR13_SATA_TX_EDGE_RATE
75 			, IMX6Q_GPR13_SATA_RX_EQ_VAL_3_0_DB
76 			| IMX6Q_GPR13_SATA_RX_LOS_LVL_SATA2M
77 			| IMX6Q_GPR13_SATA_RX_DPLL_MODE_2P_4F
78 			| IMX6Q_GPR13_SATA_SPD_MODE_3P0G
79 			| IMX6Q_GPR13_SATA_MPLL_SS_EN
80 			| IMX6Q_GPR13_SATA_TX_ATTEN_9_16
81 			| IMX6Q_GPR13_SATA_TX_BOOST_3_33_DB
82 			| IMX6Q_GPR13_SATA_TX_LVL_1_025_V);
83 	regmap_update_bits(imxpriv->gpr, 0x34, IMX6Q_GPR13_SATA_MPLL_CLK_EN,
84 			IMX6Q_GPR13_SATA_MPLL_CLK_EN);
85 	usleep_range(100, 200);
86 
87 	/*
88 	 * Configure the HWINIT bits of the HOST_CAP and HOST_PORTS_IMPL,
89 	 * and IP vendor specific register HOST_TIMER1MS.
90 	 * Configure CAP_SSS (support stagered spin up).
91 	 * Implement the port0.
92 	 * Get the ahb clock rate, and configure the TIMER1MS register.
93 	 */
94 	reg_val = readl(mmio + HOST_CAP);
95 	if (!(reg_val & HOST_CAP_SSS)) {
96 		reg_val |= HOST_CAP_SSS;
97 		writel(reg_val, mmio + HOST_CAP);
98 	}
99 	reg_val = readl(mmio + HOST_PORTS_IMPL);
100 	if (!(reg_val & 0x1)) {
101 		reg_val |= 0x1;
102 		writel(reg_val, mmio + HOST_PORTS_IMPL);
103 	}
104 
105 	reg_val = clk_get_rate(imxpriv->ahb_clk) / 1000;
106 	writel(reg_val, mmio + HOST_TIMER1MS);
107 
108 	return 0;
109 }
110 
111 static void imx6q_sata_exit(struct device *dev)
112 {
113 	struct imx_ahci_priv *imxpriv =  dev_get_drvdata(dev->parent);
114 
115 	regmap_update_bits(imxpriv->gpr, 0x34, IMX6Q_GPR13_SATA_MPLL_CLK_EN,
116 			!IMX6Q_GPR13_SATA_MPLL_CLK_EN);
117 	clk_disable_unprepare(imxpriv->sata_ref_clk);
118 }
119 
120 static struct ahci_platform_data imx6q_sata_pdata = {
121 	.init = imx6q_sata_init,
122 	.exit = imx6q_sata_exit,
123 };
124 
125 static const struct of_device_id imx_ahci_of_match[] = {
126 	{ .compatible = "fsl,imx6q-ahci", .data = &imx6q_sata_pdata},
127 	{},
128 };
129 MODULE_DEVICE_TABLE(of, imx_ahci_of_match);
130 
131 static int imx_ahci_probe(struct platform_device *pdev)
132 {
133 	struct device *dev = &pdev->dev;
134 	struct resource *mem, *irq, res[2];
135 	const struct of_device_id *of_id;
136 	const struct ahci_platform_data *pdata = NULL;
137 	struct imx_ahci_priv *imxpriv;
138 	struct device *ahci_dev;
139 	struct platform_device *ahci_pdev;
140 	int ret;
141 
142 	imxpriv = devm_kzalloc(dev, sizeof(*imxpriv), GFP_KERNEL);
143 	if (!imxpriv) {
144 		dev_err(dev, "can't alloc ahci_host_priv\n");
145 		return -ENOMEM;
146 	}
147 
148 	ahci_pdev = platform_device_alloc("ahci", -1);
149 	if (!ahci_pdev)
150 		return -ENODEV;
151 
152 	ahci_dev = &ahci_pdev->dev;
153 	ahci_dev->parent = dev;
154 
155 	imxpriv->ahb_clk = devm_clk_get(dev, "ahb");
156 	if (IS_ERR(imxpriv->ahb_clk)) {
157 		dev_err(dev, "can't get ahb clock.\n");
158 		ret = PTR_ERR(imxpriv->ahb_clk);
159 		goto err_out;
160 	}
161 
162 	imxpriv->sata_ref_clk = devm_clk_get(dev, "sata_ref");
163 	if (IS_ERR(imxpriv->sata_ref_clk)) {
164 		dev_err(dev, "can't get sata_ref clock.\n");
165 		ret = PTR_ERR(imxpriv->sata_ref_clk);
166 		goto err_out;
167 	}
168 
169 	imxpriv->ahci_pdev = ahci_pdev;
170 	platform_set_drvdata(pdev, imxpriv);
171 
172 	of_id = of_match_device(imx_ahci_of_match, dev);
173 	if (of_id) {
174 		pdata = of_id->data;
175 	} else {
176 		ret = -EINVAL;
177 		goto err_out;
178 	}
179 
180 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
181 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
182 	if (!mem || !irq) {
183 		dev_err(dev, "no mmio/irq resource\n");
184 		ret = -ENOMEM;
185 		goto err_out;
186 	}
187 
188 	res[0] = *mem;
189 	res[1] = *irq;
190 
191 	ahci_dev->coherent_dma_mask = DMA_BIT_MASK(32);
192 	ahci_dev->dma_mask = &ahci_dev->coherent_dma_mask;
193 	ahci_dev->of_node = dev->of_node;
194 
195 	ret = platform_device_add_resources(ahci_pdev, res, 2);
196 	if (ret)
197 		goto err_out;
198 
199 	ret = platform_device_add_data(ahci_pdev, pdata, sizeof(*pdata));
200 	if (ret)
201 		goto err_out;
202 
203 	ret = platform_device_add(ahci_pdev);
204 	if (ret) {
205 err_out:
206 		platform_device_put(ahci_pdev);
207 		return ret;
208 	}
209 
210 	return 0;
211 }
212 
213 static int imx_ahci_remove(struct platform_device *pdev)
214 {
215 	struct imx_ahci_priv *imxpriv = platform_get_drvdata(pdev);
216 	struct platform_device *ahci_pdev = imxpriv->ahci_pdev;
217 
218 	platform_device_unregister(ahci_pdev);
219 	return 0;
220 }
221 
222 static struct platform_driver imx_ahci_driver = {
223 	.probe = imx_ahci_probe,
224 	.remove = imx_ahci_remove,
225 	.driver = {
226 		.name = "ahci-imx",
227 		.owner = THIS_MODULE,
228 		.of_match_table = imx_ahci_of_match,
229 	},
230 };
231 module_platform_driver(imx_ahci_driver);
232 
233 MODULE_DESCRIPTION("Freescale i.MX AHCI SATA platform driver");
234 MODULE_AUTHOR("Richard Zhu <Hong-Xing.Zhu@freescale.com>");
235 MODULE_LICENSE("GPL");
236 MODULE_ALIAS("ahci:imx");
237