1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for Synopsys DesignWare Cores Mobile Storage Host Controller
4  *
5  * Copyright (C) 2018 Synaptics Incorporated
6  *
7  * Author: Jisheng Zhang <jszhang@kernel.org>
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/sizes.h>
16 
17 #include "sdhci-pltfm.h"
18 
19 #define SDHCI_DWCMSHC_ARG2_STUFF	GENMASK(31, 16)
20 
21 /* DWCMSHC specific Mode Select value */
22 #define DWCMSHC_CTRL_HS400		0x7
23 
24 #define BOUNDARY_OK(addr, len) \
25 	((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
26 
27 struct dwcmshc_priv {
28 	struct clk	*bus_clk;
29 };
30 
31 /*
32  * If DMA addr spans 128MB boundary, we split the DMA transfer into two
33  * so that each DMA transfer doesn't exceed the boundary.
34  */
35 static void dwcmshc_adma_write_desc(struct sdhci_host *host, void **desc,
36 				    dma_addr_t addr, int len, unsigned int cmd)
37 {
38 	int tmplen, offset;
39 
40 	if (likely(!len || BOUNDARY_OK(addr, len))) {
41 		sdhci_adma_write_desc(host, desc, addr, len, cmd);
42 		return;
43 	}
44 
45 	offset = addr & (SZ_128M - 1);
46 	tmplen = SZ_128M - offset;
47 	sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
48 
49 	addr += tmplen;
50 	len -= tmplen;
51 	sdhci_adma_write_desc(host, desc, addr, len, cmd);
52 }
53 
54 static void dwcmshc_check_auto_cmd23(struct mmc_host *mmc,
55 				     struct mmc_request *mrq)
56 {
57 	struct sdhci_host *host = mmc_priv(mmc);
58 
59 	/*
60 	 * No matter V4 is enabled or not, ARGUMENT2 register is 32-bit
61 	 * block count register which doesn't support stuff bits of
62 	 * CMD23 argument on dwcmsch host controller.
63 	 */
64 	if (mrq->sbc && (mrq->sbc->arg & SDHCI_DWCMSHC_ARG2_STUFF))
65 		host->flags &= ~SDHCI_AUTO_CMD23;
66 	else
67 		host->flags |= SDHCI_AUTO_CMD23;
68 }
69 
70 static void dwcmshc_request(struct mmc_host *mmc, struct mmc_request *mrq)
71 {
72 	dwcmshc_check_auto_cmd23(mmc, mrq);
73 
74 	sdhci_request(mmc, mrq);
75 }
76 
77 static void dwcmshc_set_uhs_signaling(struct sdhci_host *host,
78 				      unsigned int timing)
79 {
80 	u16 ctrl_2;
81 
82 	ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
83 	/* Select Bus Speed Mode for host */
84 	ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
85 	if ((timing == MMC_TIMING_MMC_HS200) ||
86 	    (timing == MMC_TIMING_UHS_SDR104))
87 		ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
88 	else if (timing == MMC_TIMING_UHS_SDR12)
89 		ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
90 	else if ((timing == MMC_TIMING_UHS_SDR25) ||
91 		 (timing == MMC_TIMING_MMC_HS))
92 		ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
93 	else if (timing == MMC_TIMING_UHS_SDR50)
94 		ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
95 	else if ((timing == MMC_TIMING_UHS_DDR50) ||
96 		 (timing == MMC_TIMING_MMC_DDR52))
97 		ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
98 	else if (timing == MMC_TIMING_MMC_HS400)
99 		ctrl_2 |= DWCMSHC_CTRL_HS400;
100 	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
101 }
102 
103 static const struct sdhci_ops sdhci_dwcmshc_ops = {
104 	.set_clock		= sdhci_set_clock,
105 	.set_bus_width		= sdhci_set_bus_width,
106 	.set_uhs_signaling	= dwcmshc_set_uhs_signaling,
107 	.get_max_clock		= sdhci_pltfm_clk_get_max_clock,
108 	.reset			= sdhci_reset,
109 	.adma_write_desc	= dwcmshc_adma_write_desc,
110 };
111 
112 static const struct sdhci_pltfm_data sdhci_dwcmshc_pdata = {
113 	.ops = &sdhci_dwcmshc_ops,
114 	.quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
115 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
116 };
117 
118 static int dwcmshc_probe(struct platform_device *pdev)
119 {
120 	struct sdhci_pltfm_host *pltfm_host;
121 	struct sdhci_host *host;
122 	struct dwcmshc_priv *priv;
123 	int err;
124 	u32 extra;
125 
126 	host = sdhci_pltfm_init(pdev, &sdhci_dwcmshc_pdata,
127 				sizeof(struct dwcmshc_priv));
128 	if (IS_ERR(host))
129 		return PTR_ERR(host);
130 
131 	/*
132 	 * extra adma table cnt for cross 128M boundary handling.
133 	 */
134 	extra = DIV_ROUND_UP_ULL(dma_get_required_mask(&pdev->dev), SZ_128M);
135 	if (extra > SDHCI_MAX_SEGS)
136 		extra = SDHCI_MAX_SEGS;
137 	host->adma_table_cnt += extra;
138 
139 	pltfm_host = sdhci_priv(host);
140 	priv = sdhci_pltfm_priv(pltfm_host);
141 
142 	pltfm_host->clk = devm_clk_get(&pdev->dev, "core");
143 	if (IS_ERR(pltfm_host->clk)) {
144 		err = PTR_ERR(pltfm_host->clk);
145 		dev_err(&pdev->dev, "failed to get core clk: %d\n", err);
146 		goto free_pltfm;
147 	}
148 	err = clk_prepare_enable(pltfm_host->clk);
149 	if (err)
150 		goto free_pltfm;
151 
152 	priv->bus_clk = devm_clk_get(&pdev->dev, "bus");
153 	if (!IS_ERR(priv->bus_clk))
154 		clk_prepare_enable(priv->bus_clk);
155 
156 	err = mmc_of_parse(host->mmc);
157 	if (err)
158 		goto err_clk;
159 
160 	sdhci_get_of_property(pdev);
161 
162 	host->mmc_host_ops.request = dwcmshc_request;
163 
164 	err = sdhci_add_host(host);
165 	if (err)
166 		goto err_clk;
167 
168 	return 0;
169 
170 err_clk:
171 	clk_disable_unprepare(pltfm_host->clk);
172 	clk_disable_unprepare(priv->bus_clk);
173 free_pltfm:
174 	sdhci_pltfm_free(pdev);
175 	return err;
176 }
177 
178 static int dwcmshc_remove(struct platform_device *pdev)
179 {
180 	struct sdhci_host *host = platform_get_drvdata(pdev);
181 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
182 	struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
183 
184 	sdhci_remove_host(host, 0);
185 
186 	clk_disable_unprepare(pltfm_host->clk);
187 	clk_disable_unprepare(priv->bus_clk);
188 
189 	sdhci_pltfm_free(pdev);
190 
191 	return 0;
192 }
193 
194 #ifdef CONFIG_PM_SLEEP
195 static int dwcmshc_suspend(struct device *dev)
196 {
197 	struct sdhci_host *host = dev_get_drvdata(dev);
198 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
199 	struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
200 	int ret;
201 
202 	ret = sdhci_suspend_host(host);
203 	if (ret)
204 		return ret;
205 
206 	clk_disable_unprepare(pltfm_host->clk);
207 	if (!IS_ERR(priv->bus_clk))
208 		clk_disable_unprepare(priv->bus_clk);
209 
210 	return ret;
211 }
212 
213 static int dwcmshc_resume(struct device *dev)
214 {
215 	struct sdhci_host *host = dev_get_drvdata(dev);
216 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
217 	struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
218 	int ret;
219 
220 	ret = clk_prepare_enable(pltfm_host->clk);
221 	if (ret)
222 		return ret;
223 
224 	if (!IS_ERR(priv->bus_clk)) {
225 		ret = clk_prepare_enable(priv->bus_clk);
226 		if (ret)
227 			return ret;
228 	}
229 
230 	return sdhci_resume_host(host);
231 }
232 #endif
233 
234 static SIMPLE_DEV_PM_OPS(dwcmshc_pmops, dwcmshc_suspend, dwcmshc_resume);
235 
236 static const struct of_device_id sdhci_dwcmshc_dt_ids[] = {
237 	{ .compatible = "snps,dwcmshc-sdhci" },
238 	{}
239 };
240 MODULE_DEVICE_TABLE(of, sdhci_dwcmshc_dt_ids);
241 
242 static struct platform_driver sdhci_dwcmshc_driver = {
243 	.driver	= {
244 		.name	= "sdhci-dwcmshc",
245 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
246 		.of_match_table = sdhci_dwcmshc_dt_ids,
247 		.pm = &dwcmshc_pmops,
248 	},
249 	.probe	= dwcmshc_probe,
250 	.remove	= dwcmshc_remove,
251 };
252 module_platform_driver(sdhci_dwcmshc_driver);
253 
254 MODULE_DESCRIPTION("SDHCI platform driver for Synopsys DWC MSHC");
255 MODULE_AUTHOR("Jisheng Zhang <jszhang@kernel.org>");
256 MODULE_LICENSE("GPL v2");
257