1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Copyright (C) 2019 ASPEED Technology Inc. */
3 /* Copyright (C) 2019 IBM Corp. */
4 
5 #include <linux/clk.h>
6 #include <linux/delay.h>
7 #include <linux/device.h>
8 #include <linux/io.h>
9 #include <linux/mmc/host.h>
10 #include <linux/module.h>
11 #include <linux/of_address.h>
12 #include <linux/of.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/spinlock.h>
16 
17 #include "sdhci-pltfm.h"
18 
19 #define ASPEED_SDC_INFO		0x00
20 #define   ASPEED_SDC_S1MMC8	BIT(25)
21 #define   ASPEED_SDC_S0MMC8	BIT(24)
22 
23 struct aspeed_sdc {
24 	struct clk *clk;
25 	struct resource *res;
26 
27 	spinlock_t lock;
28 	void __iomem *regs;
29 };
30 
31 struct aspeed_sdhci {
32 	struct aspeed_sdc *parent;
33 	u32 width_mask;
34 };
35 
36 static void aspeed_sdc_configure_8bit_mode(struct aspeed_sdc *sdc,
37 					   struct aspeed_sdhci *sdhci,
38 					   bool bus8)
39 {
40 	u32 info;
41 
42 	/* Set/clear 8 bit mode */
43 	spin_lock(&sdc->lock);
44 	info = readl(sdc->regs + ASPEED_SDC_INFO);
45 	if (bus8)
46 		info |= sdhci->width_mask;
47 	else
48 		info &= ~sdhci->width_mask;
49 	writel(info, sdc->regs + ASPEED_SDC_INFO);
50 	spin_unlock(&sdc->lock);
51 }
52 
53 static void aspeed_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
54 {
55 	struct sdhci_pltfm_host *pltfm_host;
56 	unsigned long parent;
57 	int div;
58 	u16 clk;
59 
60 	pltfm_host = sdhci_priv(host);
61 	parent = clk_get_rate(pltfm_host->clk);
62 
63 	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
64 
65 	if (clock == 0)
66 		return;
67 
68 	if (WARN_ON(clock > host->max_clk))
69 		clock = host->max_clk;
70 
71 	for (div = 2; div < 256; div *= 2) {
72 		if ((parent / div) <= clock)
73 			break;
74 	}
75 	div >>= 1;
76 
77 	clk = div << SDHCI_DIVIDER_SHIFT;
78 
79 	sdhci_enable_clk(host, clk);
80 }
81 
82 static unsigned int aspeed_sdhci_get_max_clock(struct sdhci_host *host)
83 {
84 	if (host->mmc->f_max)
85 		return host->mmc->f_max;
86 
87 	return sdhci_pltfm_clk_get_max_clock(host);
88 }
89 
90 static void aspeed_sdhci_set_bus_width(struct sdhci_host *host, int width)
91 {
92 	struct sdhci_pltfm_host *pltfm_priv;
93 	struct aspeed_sdhci *aspeed_sdhci;
94 	struct aspeed_sdc *aspeed_sdc;
95 	u8 ctrl;
96 
97 	pltfm_priv = sdhci_priv(host);
98 	aspeed_sdhci = sdhci_pltfm_priv(pltfm_priv);
99 	aspeed_sdc = aspeed_sdhci->parent;
100 
101 	/* Set/clear 8-bit mode */
102 	aspeed_sdc_configure_8bit_mode(aspeed_sdc, aspeed_sdhci,
103 				       width == MMC_BUS_WIDTH_8);
104 
105 	/* Set/clear 1 or 4 bit mode */
106 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
107 	if (width == MMC_BUS_WIDTH_4)
108 		ctrl |= SDHCI_CTRL_4BITBUS;
109 	else
110 		ctrl &= ~SDHCI_CTRL_4BITBUS;
111 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
112 }
113 
114 static u32 aspeed_sdhci_readl(struct sdhci_host *host, int reg)
115 {
116 	u32 val = readl(host->ioaddr + reg);
117 
118 	if (unlikely(reg == SDHCI_PRESENT_STATE) &&
119 	    (host->mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH))
120 		val ^= SDHCI_CARD_PRESENT;
121 
122 	return val;
123 }
124 
125 static const struct sdhci_ops aspeed_sdhci_ops = {
126 	.read_l = aspeed_sdhci_readl,
127 	.set_clock = aspeed_sdhci_set_clock,
128 	.get_max_clock = aspeed_sdhci_get_max_clock,
129 	.set_bus_width = aspeed_sdhci_set_bus_width,
130 	.get_timeout_clock = sdhci_pltfm_clk_get_max_clock,
131 	.reset = sdhci_reset,
132 	.set_uhs_signaling = sdhci_set_uhs_signaling,
133 };
134 
135 static const struct sdhci_pltfm_data aspeed_sdhci_pdata = {
136 	.ops = &aspeed_sdhci_ops,
137 	.quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
138 };
139 
140 static inline int aspeed_sdhci_calculate_slot(struct aspeed_sdhci *dev,
141 					      struct resource *res)
142 {
143 	resource_size_t delta;
144 
145 	if (!res || resource_type(res) != IORESOURCE_MEM)
146 		return -EINVAL;
147 
148 	if (res->start < dev->parent->res->start)
149 		return -EINVAL;
150 
151 	delta = res->start - dev->parent->res->start;
152 	if (delta & (0x100 - 1))
153 		return -EINVAL;
154 
155 	return (delta / 0x100) - 1;
156 }
157 
158 static int aspeed_sdhci_probe(struct platform_device *pdev)
159 {
160 	struct sdhci_pltfm_host *pltfm_host;
161 	struct aspeed_sdhci *dev;
162 	struct sdhci_host *host;
163 	struct resource *res;
164 	int slot;
165 	int ret;
166 
167 	host = sdhci_pltfm_init(pdev, &aspeed_sdhci_pdata, sizeof(*dev));
168 	if (IS_ERR(host))
169 		return PTR_ERR(host);
170 
171 	pltfm_host = sdhci_priv(host);
172 	dev = sdhci_pltfm_priv(pltfm_host);
173 	dev->parent = dev_get_drvdata(pdev->dev.parent);
174 
175 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
176 	slot = aspeed_sdhci_calculate_slot(dev, res);
177 
178 	if (slot < 0)
179 		return slot;
180 	else if (slot >= 2)
181 		return -EINVAL;
182 
183 	dev_info(&pdev->dev, "Configuring for slot %d\n", slot);
184 	dev->width_mask = !slot ? ASPEED_SDC_S0MMC8 : ASPEED_SDC_S1MMC8;
185 
186 	sdhci_get_of_property(pdev);
187 
188 	pltfm_host->clk = devm_clk_get(&pdev->dev, NULL);
189 	if (IS_ERR(pltfm_host->clk))
190 		return PTR_ERR(pltfm_host->clk);
191 
192 	ret = clk_prepare_enable(pltfm_host->clk);
193 	if (ret) {
194 		dev_err(&pdev->dev, "Unable to enable SDIO clock\n");
195 		goto err_pltfm_free;
196 	}
197 
198 	ret = mmc_of_parse(host->mmc);
199 	if (ret)
200 		goto err_sdhci_add;
201 
202 	ret = sdhci_add_host(host);
203 	if (ret)
204 		goto err_sdhci_add;
205 
206 	return 0;
207 
208 err_sdhci_add:
209 	clk_disable_unprepare(pltfm_host->clk);
210 err_pltfm_free:
211 	sdhci_pltfm_free(pdev);
212 	return ret;
213 }
214 
215 static int aspeed_sdhci_remove(struct platform_device *pdev)
216 {
217 	struct sdhci_pltfm_host *pltfm_host;
218 	struct sdhci_host *host;
219 	int dead = 0;
220 
221 	host = platform_get_drvdata(pdev);
222 	pltfm_host = sdhci_priv(host);
223 
224 	sdhci_remove_host(host, dead);
225 
226 	clk_disable_unprepare(pltfm_host->clk);
227 
228 	sdhci_pltfm_free(pdev);
229 
230 	return 0;
231 }
232 
233 static const struct of_device_id aspeed_sdhci_of_match[] = {
234 	{ .compatible = "aspeed,ast2400-sdhci", },
235 	{ .compatible = "aspeed,ast2500-sdhci", },
236 	{ .compatible = "aspeed,ast2600-sdhci", },
237 	{ }
238 };
239 
240 static struct platform_driver aspeed_sdhci_driver = {
241 	.driver		= {
242 		.name	= "sdhci-aspeed",
243 		.of_match_table = aspeed_sdhci_of_match,
244 	},
245 	.probe		= aspeed_sdhci_probe,
246 	.remove		= aspeed_sdhci_remove,
247 };
248 
249 static int aspeed_sdc_probe(struct platform_device *pdev)
250 
251 {
252 	struct device_node *parent, *child;
253 	struct aspeed_sdc *sdc;
254 	int ret;
255 
256 	sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL);
257 	if (!sdc)
258 		return -ENOMEM;
259 
260 	spin_lock_init(&sdc->lock);
261 
262 	sdc->clk = devm_clk_get(&pdev->dev, NULL);
263 	if (IS_ERR(sdc->clk))
264 		return PTR_ERR(sdc->clk);
265 
266 	ret = clk_prepare_enable(sdc->clk);
267 	if (ret) {
268 		dev_err(&pdev->dev, "Unable to enable SDCLK\n");
269 		return ret;
270 	}
271 
272 	sdc->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
273 	sdc->regs = devm_ioremap_resource(&pdev->dev, sdc->res);
274 	if (IS_ERR(sdc->regs)) {
275 		ret = PTR_ERR(sdc->regs);
276 		goto err_clk;
277 	}
278 
279 	dev_set_drvdata(&pdev->dev, sdc);
280 
281 	parent = pdev->dev.of_node;
282 	for_each_available_child_of_node(parent, child) {
283 		struct platform_device *cpdev;
284 
285 		cpdev = of_platform_device_create(child, NULL, &pdev->dev);
286 		if (!cpdev) {
287 			of_node_put(child);
288 			ret = -ENODEV;
289 			goto err_clk;
290 		}
291 	}
292 
293 	return 0;
294 
295 err_clk:
296 	clk_disable_unprepare(sdc->clk);
297 	return ret;
298 }
299 
300 static int aspeed_sdc_remove(struct platform_device *pdev)
301 {
302 	struct aspeed_sdc *sdc = dev_get_drvdata(&pdev->dev);
303 
304 	clk_disable_unprepare(sdc->clk);
305 
306 	return 0;
307 }
308 
309 static const struct of_device_id aspeed_sdc_of_match[] = {
310 	{ .compatible = "aspeed,ast2400-sd-controller", },
311 	{ .compatible = "aspeed,ast2500-sd-controller", },
312 	{ .compatible = "aspeed,ast2600-sd-controller", },
313 	{ }
314 };
315 
316 MODULE_DEVICE_TABLE(of, aspeed_sdc_of_match);
317 
318 static struct platform_driver aspeed_sdc_driver = {
319 	.driver		= {
320 		.name	= "sd-controller-aspeed",
321 		.pm	= &sdhci_pltfm_pmops,
322 		.of_match_table = aspeed_sdc_of_match,
323 	},
324 	.probe		= aspeed_sdc_probe,
325 	.remove		= aspeed_sdc_remove,
326 };
327 
328 static int __init aspeed_sdc_init(void)
329 {
330 	int rc;
331 
332 	rc = platform_driver_register(&aspeed_sdhci_driver);
333 	if (rc < 0)
334 		return rc;
335 
336 	rc = platform_driver_register(&aspeed_sdc_driver);
337 	if (rc < 0)
338 		platform_driver_unregister(&aspeed_sdhci_driver);
339 
340 	return rc;
341 }
342 module_init(aspeed_sdc_init);
343 
344 static void __exit aspeed_sdc_exit(void)
345 {
346 	platform_driver_unregister(&aspeed_sdc_driver);
347 	platform_driver_unregister(&aspeed_sdhci_driver);
348 }
349 module_exit(aspeed_sdc_exit);
350 
351 MODULE_DESCRIPTION("Driver for the ASPEED SD/SDIO/SDHCI Controllers");
352 MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
353 MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
354 MODULE_LICENSE("GPL");
355