1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018 Oleksij Rempel <linux@rempel-privat.de>
4  *
5  * Driver for Alcor Micro AU6601 and AU6621 controllers
6  */
7 
8 #include <linux/delay.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/irq.h>
12 #include <linux/mfd/core.h>
13 #include <linux/module.h>
14 #include <linux/pci.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm.h>
17 
18 #include <linux/alcor_pci.h>
19 
20 #define DRV_NAME_ALCOR_PCI			"alcor_pci"
21 
22 static DEFINE_IDA(alcor_pci_idr);
23 
24 static struct mfd_cell alcor_pci_cells[] = {
25 	[ALCOR_SD_CARD] = {
26 		.name = DRV_NAME_ALCOR_PCI_SDMMC,
27 	},
28 	[ALCOR_MS_CARD] = {
29 		.name = DRV_NAME_ALCOR_PCI_MS,
30 	},
31 };
32 
33 static const struct alcor_dev_cfg alcor_cfg = {
34 	.dma = 0,
35 };
36 
37 static const struct alcor_dev_cfg au6621_cfg = {
38 	.dma = 1,
39 };
40 
41 static const struct alcor_dev_cfg au6625_cfg = {
42 	.dma = 0,
43 };
44 
45 static const struct pci_device_id pci_ids[] = {
46 	{ PCI_DEVICE(PCI_ID_ALCOR_MICRO, PCI_ID_AU6601),
47 		.driver_data = (kernel_ulong_t)&alcor_cfg },
48 	{ PCI_DEVICE(PCI_ID_ALCOR_MICRO, PCI_ID_AU6621),
49 		.driver_data = (kernel_ulong_t)&au6621_cfg },
50 	{ PCI_DEVICE(PCI_ID_ALCOR_MICRO, PCI_ID_AU6625),
51 		.driver_data = (kernel_ulong_t)&au6625_cfg },
52 	{},
53 };
54 MODULE_DEVICE_TABLE(pci, pci_ids);
55 
56 void alcor_write8(struct alcor_pci_priv *priv, u8 val, unsigned int addr)
57 {
58 	writeb(val, priv->iobase + addr);
59 }
60 EXPORT_SYMBOL_GPL(alcor_write8);
61 
62 void alcor_write16(struct alcor_pci_priv *priv, u16 val, unsigned int addr)
63 {
64 	writew(val, priv->iobase + addr);
65 }
66 EXPORT_SYMBOL_GPL(alcor_write16);
67 
68 void alcor_write32(struct alcor_pci_priv *priv, u32 val, unsigned int addr)
69 {
70 	writel(val, priv->iobase + addr);
71 }
72 EXPORT_SYMBOL_GPL(alcor_write32);
73 
74 void alcor_write32be(struct alcor_pci_priv *priv, u32 val, unsigned int addr)
75 {
76 	iowrite32be(val, priv->iobase + addr);
77 }
78 EXPORT_SYMBOL_GPL(alcor_write32be);
79 
80 u8 alcor_read8(struct alcor_pci_priv *priv, unsigned int addr)
81 {
82 	return readb(priv->iobase + addr);
83 }
84 EXPORT_SYMBOL_GPL(alcor_read8);
85 
86 u32 alcor_read32(struct alcor_pci_priv *priv, unsigned int addr)
87 {
88 	return readl(priv->iobase + addr);
89 }
90 EXPORT_SYMBOL_GPL(alcor_read32);
91 
92 u32 alcor_read32be(struct alcor_pci_priv *priv, unsigned int addr)
93 {
94 	return ioread32be(priv->iobase + addr);
95 }
96 EXPORT_SYMBOL_GPL(alcor_read32be);
97 
98 static int alcor_pci_find_cap_offset(struct alcor_pci_priv *priv,
99 				     struct pci_dev *pci)
100 {
101 	int where;
102 	u8 val8;
103 	u32 val32;
104 
105 	where = ALCOR_CAP_START_OFFSET;
106 	pci_read_config_byte(pci, where, &val8);
107 	if (!val8)
108 		return 0;
109 
110 	where = (int)val8;
111 	while (1) {
112 		pci_read_config_dword(pci, where, &val32);
113 		if (val32 == 0xffffffff) {
114 			dev_dbg(priv->dev, "find_cap_offset invalid value %x.\n",
115 				val32);
116 			return 0;
117 		}
118 
119 		if ((val32 & 0xff) == 0x10) {
120 			dev_dbg(priv->dev, "pcie cap offset: %x\n", where);
121 			return where;
122 		}
123 
124 		if ((val32 & 0xff00) == 0x00) {
125 			dev_dbg(priv->dev, "pci_find_cap_offset invalid value %x.\n",
126 				val32);
127 			break;
128 		}
129 		where = (int)((val32 >> 8) & 0xff);
130 	}
131 
132 	return 0;
133 }
134 
135 static void alcor_pci_init_check_aspm(struct alcor_pci_priv *priv)
136 {
137 	struct pci_dev *pci;
138 	int where;
139 	u32 val32;
140 
141 	priv->pdev_cap_off    = alcor_pci_find_cap_offset(priv, priv->pdev);
142 	/*
143 	 * A device might be attached to root complex directly and
144 	 * priv->parent_pdev will be NULL. In this case we don't check its
145 	 * capability and disable ASPM completely.
146 	 */
147 	if (priv->parent_pdev)
148 		priv->parent_cap_off = alcor_pci_find_cap_offset(priv,
149 							 priv->parent_pdev);
150 
151 	if ((priv->pdev_cap_off == 0) || (priv->parent_cap_off == 0)) {
152 		dev_dbg(priv->dev, "pci_cap_off: %x, parent_cap_off: %x\n",
153 			priv->pdev_cap_off, priv->parent_cap_off);
154 		return;
155 	}
156 
157 	/* link capability */
158 	pci   = priv->pdev;
159 	where = priv->pdev_cap_off + ALCOR_PCIE_LINK_CAP_OFFSET;
160 	pci_read_config_dword(pci, where, &val32);
161 	priv->pdev_aspm_cap = (u8)(val32 >> 10) & 0x03;
162 
163 	pci   = priv->parent_pdev;
164 	where = priv->parent_cap_off + ALCOR_PCIE_LINK_CAP_OFFSET;
165 	pci_read_config_dword(pci, where, &val32);
166 	priv->parent_aspm_cap = (u8)(val32 >> 10) & 0x03;
167 
168 	if (priv->pdev_aspm_cap != priv->parent_aspm_cap) {
169 		u8 aspm_cap;
170 
171 		dev_dbg(priv->dev, "pdev_aspm_cap: %x, parent_aspm_cap: %x\n",
172 			priv->pdev_aspm_cap, priv->parent_aspm_cap);
173 		aspm_cap = priv->pdev_aspm_cap & priv->parent_aspm_cap;
174 		priv->pdev_aspm_cap    = aspm_cap;
175 		priv->parent_aspm_cap = aspm_cap;
176 	}
177 
178 	dev_dbg(priv->dev, "ext_config_dev_aspm: %x, pdev_aspm_cap: %x\n",
179 		priv->ext_config_dev_aspm, priv->pdev_aspm_cap);
180 	priv->ext_config_dev_aspm &= priv->pdev_aspm_cap;
181 }
182 
183 static void alcor_pci_aspm_ctrl(struct alcor_pci_priv *priv, u8 aspm_enable)
184 {
185 	struct pci_dev *pci;
186 	u8 aspm_ctrl, i;
187 	int where;
188 	u32 val32;
189 
190 	if ((!priv->pdev_cap_off) || (!priv->parent_cap_off)) {
191 		dev_dbg(priv->dev, "pci_cap_off: %x, parent_cap_off: %x\n",
192 			priv->pdev_cap_off, priv->parent_cap_off);
193 		return;
194 	}
195 
196 	if (!priv->pdev_aspm_cap)
197 		return;
198 
199 	aspm_ctrl = 0;
200 	if (aspm_enable) {
201 		aspm_ctrl = priv->ext_config_dev_aspm;
202 
203 		if (!aspm_ctrl) {
204 			dev_dbg(priv->dev, "aspm_ctrl == 0\n");
205 			return;
206 		}
207 	}
208 
209 	for (i = 0; i < 2; i++) {
210 
211 		if (i) {
212 			pci   = priv->parent_pdev;
213 			where = priv->parent_cap_off
214 				+ ALCOR_PCIE_LINK_CTRL_OFFSET;
215 		} else {
216 			pci   = priv->pdev;
217 			where = priv->pdev_cap_off
218 				+ ALCOR_PCIE_LINK_CTRL_OFFSET;
219 		}
220 
221 		pci_read_config_dword(pci, where, &val32);
222 		val32 &= (~0x03);
223 		val32 |= (aspm_ctrl & priv->pdev_aspm_cap);
224 		pci_write_config_byte(pci, where, (u8)val32);
225 	}
226 
227 }
228 
229 static inline void alcor_mask_sd_irqs(struct alcor_pci_priv *priv)
230 {
231 	alcor_write32(priv, 0, AU6601_REG_INT_ENABLE);
232 }
233 
234 static inline void alcor_unmask_sd_irqs(struct alcor_pci_priv *priv)
235 {
236 	alcor_write32(priv, AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK |
237 		  AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE |
238 		  AU6601_INT_OVER_CURRENT_ERR,
239 		  AU6601_REG_INT_ENABLE);
240 }
241 
242 static inline void alcor_mask_ms_irqs(struct alcor_pci_priv *priv)
243 {
244 	alcor_write32(priv, 0, AU6601_MS_INT_ENABLE);
245 }
246 
247 static inline void alcor_unmask_ms_irqs(struct alcor_pci_priv *priv)
248 {
249 	alcor_write32(priv, 0x3d00fa, AU6601_MS_INT_ENABLE);
250 }
251 
252 static int alcor_pci_probe(struct pci_dev *pdev,
253 			   const struct pci_device_id *ent)
254 {
255 	struct alcor_dev_cfg *cfg;
256 	struct alcor_pci_priv *priv;
257 	int ret, i, bar = 0;
258 
259 	cfg = (void *)ent->driver_data;
260 
261 	ret = pcim_enable_device(pdev);
262 	if (ret)
263 		return ret;
264 
265 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
266 	if (!priv)
267 		return -ENOMEM;
268 
269 	ret = ida_simple_get(&alcor_pci_idr, 0, 0, GFP_KERNEL);
270 	if (ret < 0)
271 		return ret;
272 	priv->id = ret;
273 
274 	priv->pdev = pdev;
275 	priv->parent_pdev = pdev->bus->self;
276 	priv->dev = &pdev->dev;
277 	priv->cfg = cfg;
278 	priv->irq = pdev->irq;
279 
280 	ret = pci_request_regions(pdev, DRV_NAME_ALCOR_PCI);
281 	if (ret) {
282 		dev_err(&pdev->dev, "Cannot request region\n");
283 		return -ENOMEM;
284 	}
285 
286 	if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) {
287 		dev_err(&pdev->dev, "BAR %d is not iomem. Aborting.\n", bar);
288 		ret = -ENODEV;
289 		goto error_release_regions;
290 	}
291 
292 	priv->iobase = pcim_iomap(pdev, bar, 0);
293 	if (!priv->iobase) {
294 		ret = -ENOMEM;
295 		goto error_release_regions;
296 	}
297 
298 	/* make sure irqs are disabled */
299 	alcor_write32(priv, 0, AU6601_REG_INT_ENABLE);
300 	alcor_write32(priv, 0, AU6601_MS_INT_ENABLE);
301 
302 	ret = dma_set_mask_and_coherent(priv->dev, AU6601_SDMA_MASK);
303 	if (ret) {
304 		dev_err(priv->dev, "Failed to set DMA mask\n");
305 		goto error_release_regions;
306 	}
307 
308 	pci_set_master(pdev);
309 	pci_set_drvdata(pdev, priv);
310 	alcor_pci_init_check_aspm(priv);
311 
312 	for (i = 0; i < ARRAY_SIZE(alcor_pci_cells); i++) {
313 		alcor_pci_cells[i].platform_data = priv;
314 		alcor_pci_cells[i].pdata_size = sizeof(*priv);
315 	}
316 	ret = mfd_add_devices(&pdev->dev, priv->id, alcor_pci_cells,
317 			ARRAY_SIZE(alcor_pci_cells), NULL, 0, NULL);
318 	if (ret < 0)
319 		goto error_release_regions;
320 
321 	alcor_pci_aspm_ctrl(priv, 0);
322 
323 	return 0;
324 
325 error_release_regions:
326 	pci_release_regions(pdev);
327 	return ret;
328 }
329 
330 static void alcor_pci_remove(struct pci_dev *pdev)
331 {
332 	struct alcor_pci_priv *priv;
333 
334 	priv = pci_get_drvdata(pdev);
335 
336 	alcor_pci_aspm_ctrl(priv, 1);
337 
338 	mfd_remove_devices(&pdev->dev);
339 
340 	ida_simple_remove(&alcor_pci_idr, priv->id);
341 
342 	pci_release_regions(pdev);
343 	pci_set_drvdata(pdev, NULL);
344 }
345 
346 #ifdef CONFIG_PM_SLEEP
347 static int alcor_suspend(struct device *dev)
348 {
349 	struct alcor_pci_priv *priv = dev_get_drvdata(dev);
350 
351 	alcor_pci_aspm_ctrl(priv, 1);
352 	return 0;
353 }
354 
355 static int alcor_resume(struct device *dev)
356 {
357 
358 	struct alcor_pci_priv *priv = dev_get_drvdata(dev);
359 
360 	alcor_pci_aspm_ctrl(priv, 0);
361 	return 0;
362 }
363 #endif /* CONFIG_PM_SLEEP */
364 
365 static SIMPLE_DEV_PM_OPS(alcor_pci_pm_ops, alcor_suspend, alcor_resume);
366 
367 static struct pci_driver alcor_driver = {
368 	.name	=	DRV_NAME_ALCOR_PCI,
369 	.id_table =	pci_ids,
370 	.probe	=	alcor_pci_probe,
371 	.remove =	alcor_pci_remove,
372 	.driver	=	{
373 		.pm	= &alcor_pci_pm_ops
374 	},
375 };
376 
377 module_pci_driver(alcor_driver);
378 
379 MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
380 MODULE_DESCRIPTION("PCI driver for Alcor Micro AU6601 Secure Digital Host Controller Interface");
381 MODULE_LICENSE("GPL");
382