xref: /openbmc/linux/drivers/firmware/qcom_scm.c (revision bc5aa3a0)
1 /* Copyright (c) 2010,2015, The Linux Foundation. All rights reserved.
2  * Copyright (C) 2015 Linaro Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 and
6  * only version 2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  */
14 #include <linux/platform_device.h>
15 #include <linux/module.h>
16 #include <linux/cpumask.h>
17 #include <linux/export.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/types.h>
20 #include <linux/qcom_scm.h>
21 #include <linux/of.h>
22 #include <linux/of_platform.h>
23 #include <linux/clk.h>
24 #include <linux/reset-controller.h>
25 
26 #include "qcom_scm.h"
27 
28 struct qcom_scm {
29 	struct device *dev;
30 	struct clk *core_clk;
31 	struct clk *iface_clk;
32 	struct clk *bus_clk;
33 	struct reset_controller_dev reset;
34 };
35 
36 static struct qcom_scm *__scm;
37 
38 static int qcom_scm_clk_enable(void)
39 {
40 	int ret;
41 
42 	ret = clk_prepare_enable(__scm->core_clk);
43 	if (ret)
44 		goto bail;
45 
46 	ret = clk_prepare_enable(__scm->iface_clk);
47 	if (ret)
48 		goto disable_core;
49 
50 	ret = clk_prepare_enable(__scm->bus_clk);
51 	if (ret)
52 		goto disable_iface;
53 
54 	return 0;
55 
56 disable_iface:
57 	clk_disable_unprepare(__scm->iface_clk);
58 disable_core:
59 	clk_disable_unprepare(__scm->core_clk);
60 bail:
61 	return ret;
62 }
63 
64 static void qcom_scm_clk_disable(void)
65 {
66 	clk_disable_unprepare(__scm->core_clk);
67 	clk_disable_unprepare(__scm->iface_clk);
68 	clk_disable_unprepare(__scm->bus_clk);
69 }
70 
71 /**
72  * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
73  * @entry: Entry point function for the cpus
74  * @cpus: The cpumask of cpus that will use the entry point
75  *
76  * Set the cold boot address of the cpus. Any cpu outside the supported
77  * range would be removed from the cpu present mask.
78  */
79 int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
80 {
81 	return __qcom_scm_set_cold_boot_addr(entry, cpus);
82 }
83 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
84 
85 /**
86  * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
87  * @entry: Entry point function for the cpus
88  * @cpus: The cpumask of cpus that will use the entry point
89  *
90  * Set the Linux entry point for the SCM to transfer control to when coming
91  * out of a power down. CPU power down may be executed on cpuidle or hotplug.
92  */
93 int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
94 {
95 	return __qcom_scm_set_warm_boot_addr(__scm->dev, entry, cpus);
96 }
97 EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
98 
99 /**
100  * qcom_scm_cpu_power_down() - Power down the cpu
101  * @flags - Flags to flush cache
102  *
103  * This is an end point to power down cpu. If there was a pending interrupt,
104  * the control would return from this function, otherwise, the cpu jumps to the
105  * warm boot entry point set for this cpu upon reset.
106  */
107 void qcom_scm_cpu_power_down(u32 flags)
108 {
109 	__qcom_scm_cpu_power_down(flags);
110 }
111 EXPORT_SYMBOL(qcom_scm_cpu_power_down);
112 
113 /**
114  * qcom_scm_hdcp_available() - Check if secure environment supports HDCP.
115  *
116  * Return true if HDCP is supported, false if not.
117  */
118 bool qcom_scm_hdcp_available(void)
119 {
120 	int ret = qcom_scm_clk_enable();
121 
122 	if (ret)
123 		return ret;
124 
125 	ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_HDCP,
126 						QCOM_SCM_CMD_HDCP);
127 
128 	qcom_scm_clk_disable();
129 
130 	return ret > 0 ? true : false;
131 }
132 EXPORT_SYMBOL(qcom_scm_hdcp_available);
133 
134 /**
135  * qcom_scm_hdcp_req() - Send HDCP request.
136  * @req: HDCP request array
137  * @req_cnt: HDCP request array count
138  * @resp: response buffer passed to SCM
139  *
140  * Write HDCP register(s) through SCM.
141  */
142 int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
143 {
144 	int ret = qcom_scm_clk_enable();
145 
146 	if (ret)
147 		return ret;
148 
149 	ret = __qcom_scm_hdcp_req(__scm->dev, req, req_cnt, resp);
150 	qcom_scm_clk_disable();
151 	return ret;
152 }
153 EXPORT_SYMBOL(qcom_scm_hdcp_req);
154 
155 /**
156  * qcom_scm_pas_supported() - Check if the peripheral authentication service is
157  *			      available for the given peripherial
158  * @peripheral:	peripheral id
159  *
160  * Returns true if PAS is supported for this peripheral, otherwise false.
161  */
162 bool qcom_scm_pas_supported(u32 peripheral)
163 {
164 	int ret;
165 
166 	ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_PIL,
167 					   QCOM_SCM_PAS_IS_SUPPORTED_CMD);
168 	if (ret <= 0)
169 		return false;
170 
171 	return __qcom_scm_pas_supported(__scm->dev, peripheral);
172 }
173 EXPORT_SYMBOL(qcom_scm_pas_supported);
174 
175 /**
176  * qcom_scm_pas_init_image() - Initialize peripheral authentication service
177  *			       state machine for a given peripheral, using the
178  *			       metadata
179  * @peripheral: peripheral id
180  * @metadata:	pointer to memory containing ELF header, program header table
181  *		and optional blob of data used for authenticating the metadata
182  *		and the rest of the firmware
183  * @size:	size of the metadata
184  *
185  * Returns 0 on success.
186  */
187 int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size)
188 {
189 	dma_addr_t mdata_phys;
190 	void *mdata_buf;
191 	int ret;
192 
193 	/*
194 	 * During the scm call memory protection will be enabled for the meta
195 	 * data blob, so make sure it's physically contiguous, 4K aligned and
196 	 * non-cachable to avoid XPU violations.
197 	 */
198 	mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
199 				       GFP_KERNEL);
200 	if (!mdata_buf) {
201 		dev_err(__scm->dev, "Allocation of metadata buffer failed.\n");
202 		return -ENOMEM;
203 	}
204 	memcpy(mdata_buf, metadata, size);
205 
206 	ret = qcom_scm_clk_enable();
207 	if (ret)
208 		goto free_metadata;
209 
210 	ret = __qcom_scm_pas_init_image(__scm->dev, peripheral, mdata_phys);
211 
212 	qcom_scm_clk_disable();
213 
214 free_metadata:
215 	dma_free_coherent(__scm->dev, size, mdata_buf, mdata_phys);
216 
217 	return ret;
218 }
219 EXPORT_SYMBOL(qcom_scm_pas_init_image);
220 
221 /**
222  * qcom_scm_pas_mem_setup() - Prepare the memory related to a given peripheral
223  *			      for firmware loading
224  * @peripheral:	peripheral id
225  * @addr:	start address of memory area to prepare
226  * @size:	size of the memory area to prepare
227  *
228  * Returns 0 on success.
229  */
230 int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr, phys_addr_t size)
231 {
232 	int ret;
233 
234 	ret = qcom_scm_clk_enable();
235 	if (ret)
236 		return ret;
237 
238 	ret = __qcom_scm_pas_mem_setup(__scm->dev, peripheral, addr, size);
239 	qcom_scm_clk_disable();
240 
241 	return ret;
242 }
243 EXPORT_SYMBOL(qcom_scm_pas_mem_setup);
244 
245 /**
246  * qcom_scm_pas_auth_and_reset() - Authenticate the given peripheral firmware
247  *				   and reset the remote processor
248  * @peripheral:	peripheral id
249  *
250  * Return 0 on success.
251  */
252 int qcom_scm_pas_auth_and_reset(u32 peripheral)
253 {
254 	int ret;
255 
256 	ret = qcom_scm_clk_enable();
257 	if (ret)
258 		return ret;
259 
260 	ret = __qcom_scm_pas_auth_and_reset(__scm->dev, peripheral);
261 	qcom_scm_clk_disable();
262 
263 	return ret;
264 }
265 EXPORT_SYMBOL(qcom_scm_pas_auth_and_reset);
266 
267 /**
268  * qcom_scm_pas_shutdown() - Shut down the remote processor
269  * @peripheral: peripheral id
270  *
271  * Returns 0 on success.
272  */
273 int qcom_scm_pas_shutdown(u32 peripheral)
274 {
275 	int ret;
276 
277 	ret = qcom_scm_clk_enable();
278 	if (ret)
279 		return ret;
280 
281 	ret = __qcom_scm_pas_shutdown(__scm->dev, peripheral);
282 	qcom_scm_clk_disable();
283 
284 	return ret;
285 }
286 EXPORT_SYMBOL(qcom_scm_pas_shutdown);
287 
288 static int qcom_scm_pas_reset_assert(struct reset_controller_dev *rcdev,
289 				     unsigned long idx)
290 {
291 	if (idx != 0)
292 		return -EINVAL;
293 
294 	return __qcom_scm_pas_mss_reset(__scm->dev, 1);
295 }
296 
297 static int qcom_scm_pas_reset_deassert(struct reset_controller_dev *rcdev,
298 				       unsigned long idx)
299 {
300 	if (idx != 0)
301 		return -EINVAL;
302 
303 	return __qcom_scm_pas_mss_reset(__scm->dev, 0);
304 }
305 
306 static const struct reset_control_ops qcom_scm_pas_reset_ops = {
307 	.assert = qcom_scm_pas_reset_assert,
308 	.deassert = qcom_scm_pas_reset_deassert,
309 };
310 
311 /**
312  * qcom_scm_is_available() - Checks if SCM is available
313  */
314 bool qcom_scm_is_available(void)
315 {
316 	return !!__scm;
317 }
318 EXPORT_SYMBOL(qcom_scm_is_available);
319 
320 static int qcom_scm_probe(struct platform_device *pdev)
321 {
322 	struct qcom_scm *scm;
323 	int ret;
324 
325 	scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
326 	if (!scm)
327 		return -ENOMEM;
328 
329 	scm->core_clk = devm_clk_get(&pdev->dev, "core");
330 	if (IS_ERR(scm->core_clk)) {
331 		if (PTR_ERR(scm->core_clk) == -EPROBE_DEFER)
332 			return PTR_ERR(scm->core_clk);
333 
334 		scm->core_clk = NULL;
335 	}
336 
337 	if (of_device_is_compatible(pdev->dev.of_node, "qcom,scm")) {
338 		scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
339 		if (IS_ERR(scm->iface_clk)) {
340 			if (PTR_ERR(scm->iface_clk) != -EPROBE_DEFER)
341 				dev_err(&pdev->dev, "failed to acquire iface clk\n");
342 			return PTR_ERR(scm->iface_clk);
343 		}
344 
345 		scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
346 		if (IS_ERR(scm->bus_clk)) {
347 			if (PTR_ERR(scm->bus_clk) != -EPROBE_DEFER)
348 				dev_err(&pdev->dev, "failed to acquire bus clk\n");
349 			return PTR_ERR(scm->bus_clk);
350 		}
351 	}
352 
353 	scm->reset.ops = &qcom_scm_pas_reset_ops;
354 	scm->reset.nr_resets = 1;
355 	scm->reset.of_node = pdev->dev.of_node;
356 	reset_controller_register(&scm->reset);
357 
358 	/* vote for max clk rate for highest performance */
359 	ret = clk_set_rate(scm->core_clk, INT_MAX);
360 	if (ret)
361 		return ret;
362 
363 	__scm = scm;
364 	__scm->dev = &pdev->dev;
365 
366 	__qcom_scm_init();
367 
368 	return 0;
369 }
370 
371 static const struct of_device_id qcom_scm_dt_match[] = {
372 	{ .compatible = "qcom,scm-apq8064",},
373 	{ .compatible = "qcom,scm-msm8660",},
374 	{ .compatible = "qcom,scm-msm8960",},
375 	{ .compatible = "qcom,scm",},
376 	{}
377 };
378 
379 MODULE_DEVICE_TABLE(of, qcom_scm_dt_match);
380 
381 static struct platform_driver qcom_scm_driver = {
382 	.driver = {
383 		.name	= "qcom_scm",
384 		.of_match_table = qcom_scm_dt_match,
385 	},
386 	.probe = qcom_scm_probe,
387 };
388 
389 static int __init qcom_scm_init(void)
390 {
391 	struct device_node *np, *fw_np;
392 	int ret;
393 
394 	fw_np = of_find_node_by_name(NULL, "firmware");
395 
396 	if (!fw_np)
397 		return -ENODEV;
398 
399 	np = of_find_matching_node(fw_np, qcom_scm_dt_match);
400 
401 	if (!np) {
402 		of_node_put(fw_np);
403 		return -ENODEV;
404 	}
405 
406 	of_node_put(np);
407 
408 	ret = of_platform_populate(fw_np, qcom_scm_dt_match, NULL, NULL);
409 
410 	of_node_put(fw_np);
411 
412 	if (ret)
413 		return ret;
414 
415 	return platform_driver_register(&qcom_scm_driver);
416 }
417 
418 subsys_initcall(qcom_scm_init);
419 
420 static void __exit qcom_scm_exit(void)
421 {
422 	platform_driver_unregister(&qcom_scm_driver);
423 }
424 module_exit(qcom_scm_exit);
425 
426 MODULE_DESCRIPTION("Qualcomm SCM driver");
427 MODULE_LICENSE("GPL v2");
428