xref: /openbmc/linux/drivers/dma/dw/platform.c (revision 77d84ff8)
1 /*
2  * Platform driver for the Synopsys DesignWare DMA Controller
3  *
4  * Copyright (C) 2007-2008 Atmel Corporation
5  * Copyright (C) 2010-2011 ST Microelectronics
6  * Copyright (C) 2013 Intel Corporation
7  *
8  * Some parts of this driver are derived from the original dw_dmac.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/device.h>
17 #include <linux/clk.h>
18 #include <linux/platform_device.h>
19 #include <linux/dmaengine.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/of.h>
22 #include <linux/of_dma.h>
23 #include <linux/acpi.h>
24 #include <linux/acpi_dma.h>
25 
26 #include "internal.h"
27 
28 struct dw_dma_of_filter_args {
29 	struct dw_dma *dw;
30 	unsigned int req;
31 	unsigned int src;
32 	unsigned int dst;
33 };
34 
35 static bool dw_dma_of_filter(struct dma_chan *chan, void *param)
36 {
37 	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
38 	struct dw_dma_of_filter_args *fargs = param;
39 
40 	/* Ensure the device matches our channel */
41 	if (chan->device != &fargs->dw->dma)
42 		return false;
43 
44 	dwc->request_line = fargs->req;
45 	dwc->src_master	= fargs->src;
46 	dwc->dst_master	= fargs->dst;
47 
48 	return true;
49 }
50 
51 static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
52 					struct of_dma *ofdma)
53 {
54 	struct dw_dma *dw = ofdma->of_dma_data;
55 	struct dw_dma_of_filter_args fargs = {
56 		.dw = dw,
57 	};
58 	dma_cap_mask_t cap;
59 
60 	if (dma_spec->args_count != 3)
61 		return NULL;
62 
63 	fargs.req = dma_spec->args[0];
64 	fargs.src = dma_spec->args[1];
65 	fargs.dst = dma_spec->args[2];
66 
67 	if (WARN_ON(fargs.req >= DW_DMA_MAX_NR_REQUESTS ||
68 		    fargs.src >= dw->nr_masters ||
69 		    fargs.dst >= dw->nr_masters))
70 		return NULL;
71 
72 	dma_cap_zero(cap);
73 	dma_cap_set(DMA_SLAVE, cap);
74 
75 	/* TODO: there should be a simpler way to do this */
76 	return dma_request_channel(cap, dw_dma_of_filter, &fargs);
77 }
78 
79 #ifdef CONFIG_ACPI
80 static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
81 {
82 	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
83 	struct acpi_dma_spec *dma_spec = param;
84 
85 	if (chan->device->dev != dma_spec->dev ||
86 	    chan->chan_id != dma_spec->chan_id)
87 		return false;
88 
89 	dwc->request_line = dma_spec->slave_id;
90 	dwc->src_master = dwc_get_sms(NULL);
91 	dwc->dst_master = dwc_get_dms(NULL);
92 
93 	return true;
94 }
95 
96 static void dw_dma_acpi_controller_register(struct dw_dma *dw)
97 {
98 	struct device *dev = dw->dma.dev;
99 	struct acpi_dma_filter_info *info;
100 	int ret;
101 
102 	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
103 	if (!info)
104 		return;
105 
106 	dma_cap_zero(info->dma_cap);
107 	dma_cap_set(DMA_SLAVE, info->dma_cap);
108 	info->filter_fn = dw_dma_acpi_filter;
109 
110 	ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
111 						info);
112 	if (ret)
113 		dev_err(dev, "could not register acpi_dma_controller\n");
114 }
115 #else /* !CONFIG_ACPI */
116 static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
117 #endif /* !CONFIG_ACPI */
118 
119 #ifdef CONFIG_OF
120 static struct dw_dma_platform_data *
121 dw_dma_parse_dt(struct platform_device *pdev)
122 {
123 	struct device_node *np = pdev->dev.of_node;
124 	struct dw_dma_platform_data *pdata;
125 	u32 tmp, arr[4];
126 
127 	if (!np) {
128 		dev_err(&pdev->dev, "Missing DT data\n");
129 		return NULL;
130 	}
131 
132 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
133 	if (!pdata)
134 		return NULL;
135 
136 	if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels))
137 		return NULL;
138 
139 	if (of_property_read_bool(np, "is_private"))
140 		pdata->is_private = true;
141 
142 	if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
143 		pdata->chan_allocation_order = (unsigned char)tmp;
144 
145 	if (!of_property_read_u32(np, "chan_priority", &tmp))
146 		pdata->chan_priority = tmp;
147 
148 	if (!of_property_read_u32(np, "block_size", &tmp))
149 		pdata->block_size = tmp;
150 
151 	if (!of_property_read_u32(np, "dma-masters", &tmp)) {
152 		if (tmp > 4)
153 			return NULL;
154 
155 		pdata->nr_masters = tmp;
156 	}
157 
158 	if (!of_property_read_u32_array(np, "data_width", arr,
159 				pdata->nr_masters))
160 		for (tmp = 0; tmp < pdata->nr_masters; tmp++)
161 			pdata->data_width[tmp] = arr[tmp];
162 
163 	return pdata;
164 }
165 #else
166 static inline struct dw_dma_platform_data *
167 dw_dma_parse_dt(struct platform_device *pdev)
168 {
169 	return NULL;
170 }
171 #endif
172 
173 static int dw_probe(struct platform_device *pdev)
174 {
175 	struct dw_dma_chip *chip;
176 	struct device *dev = &pdev->dev;
177 	struct resource *mem;
178 	struct dw_dma_platform_data *pdata;
179 	int err;
180 
181 	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
182 	if (!chip)
183 		return -ENOMEM;
184 
185 	chip->irq = platform_get_irq(pdev, 0);
186 	if (chip->irq < 0)
187 		return chip->irq;
188 
189 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
190 	chip->regs = devm_ioremap_resource(dev, mem);
191 	if (IS_ERR(chip->regs))
192 		return PTR_ERR(chip->regs);
193 
194 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
195 	if (err)
196 		return err;
197 
198 	pdata = dev_get_platdata(dev);
199 	if (!pdata)
200 		pdata = dw_dma_parse_dt(pdev);
201 
202 	chip->dev = dev;
203 
204 	err = dw_dma_probe(chip, pdata);
205 	if (err)
206 		return err;
207 
208 	platform_set_drvdata(pdev, chip);
209 
210 	if (pdev->dev.of_node) {
211 		err = of_dma_controller_register(pdev->dev.of_node,
212 						 dw_dma_of_xlate, chip->dw);
213 		if (err)
214 			dev_err(&pdev->dev,
215 				"could not register of_dma_controller\n");
216 	}
217 
218 	if (ACPI_HANDLE(&pdev->dev))
219 		dw_dma_acpi_controller_register(chip->dw);
220 
221 	return 0;
222 }
223 
224 static int dw_remove(struct platform_device *pdev)
225 {
226 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
227 
228 	if (pdev->dev.of_node)
229 		of_dma_controller_free(pdev->dev.of_node);
230 
231 	return dw_dma_remove(chip);
232 }
233 
234 static void dw_shutdown(struct platform_device *pdev)
235 {
236 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
237 
238 	dw_dma_shutdown(chip);
239 }
240 
241 #ifdef CONFIG_OF
242 static const struct of_device_id dw_dma_of_id_table[] = {
243 	{ .compatible = "snps,dma-spear1340" },
244 	{}
245 };
246 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
247 #endif
248 
249 #ifdef CONFIG_ACPI
250 static const struct acpi_device_id dw_dma_acpi_id_table[] = {
251 	{ "INTL9C60", 0 },
252 	{ }
253 };
254 MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
255 #endif
256 
257 #ifdef CONFIG_PM_SLEEP
258 
259 static int dw_suspend_noirq(struct device *dev)
260 {
261 	struct platform_device *pdev = to_platform_device(dev);
262 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
263 
264 	return dw_dma_suspend(chip);
265 }
266 
267 static int dw_resume_noirq(struct device *dev)
268 {
269 	struct platform_device *pdev = to_platform_device(dev);
270 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
271 
272 	return dw_dma_resume(chip);
273 }
274 
275 #else /* !CONFIG_PM_SLEEP */
276 
277 #define dw_suspend_noirq	NULL
278 #define dw_resume_noirq		NULL
279 
280 #endif /* !CONFIG_PM_SLEEP */
281 
282 static const struct dev_pm_ops dw_dev_pm_ops = {
283 	.suspend_noirq = dw_suspend_noirq,
284 	.resume_noirq = dw_resume_noirq,
285 	.freeze_noirq = dw_suspend_noirq,
286 	.thaw_noirq = dw_resume_noirq,
287 	.restore_noirq = dw_resume_noirq,
288 	.poweroff_noirq = dw_suspend_noirq,
289 };
290 
291 static struct platform_driver dw_driver = {
292 	.probe		= dw_probe,
293 	.remove		= dw_remove,
294 	.shutdown	= dw_shutdown,
295 	.driver = {
296 		.name	= "dw_dmac",
297 		.pm	= &dw_dev_pm_ops,
298 		.of_match_table = of_match_ptr(dw_dma_of_id_table),
299 		.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
300 	},
301 };
302 
303 static int __init dw_init(void)
304 {
305 	return platform_driver_register(&dw_driver);
306 }
307 subsys_initcall(dw_init);
308 
309 static void __exit dw_exit(void)
310 {
311 	platform_driver_unregister(&dw_driver);
312 }
313 module_exit(dw_exit);
314 
315 MODULE_LICENSE("GPL v2");
316 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
317