xref: /openbmc/linux/drivers/firmware/qcom_scm.c (revision 60772e48)
1 /*
2  * Qualcomm SCM driver
3  *
4  * Copyright (c) 2010,2015, The Linux Foundation. All rights reserved.
5  * Copyright (C) 2015 Linaro Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 and
9  * only version 2 as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  */
17 #include <linux/platform_device.h>
18 #include <linux/init.h>
19 #include <linux/cpumask.h>
20 #include <linux/export.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/qcom_scm.h>
25 #include <linux/of.h>
26 #include <linux/of_address.h>
27 #include <linux/of_platform.h>
28 #include <linux/clk.h>
29 #include <linux/reset-controller.h>
30 
31 #include "qcom_scm.h"
32 
33 static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT);
34 module_param(download_mode, bool, 0);
35 
36 #define SCM_HAS_CORE_CLK	BIT(0)
37 #define SCM_HAS_IFACE_CLK	BIT(1)
38 #define SCM_HAS_BUS_CLK		BIT(2)
39 
40 struct qcom_scm {
41 	struct device *dev;
42 	struct clk *core_clk;
43 	struct clk *iface_clk;
44 	struct clk *bus_clk;
45 	struct reset_controller_dev reset;
46 
47 	u64 dload_mode_addr;
48 };
49 
50 struct qcom_scm_current_perm_info {
51 	__le32 vmid;
52 	__le32 perm;
53 	__le64 ctx;
54 	__le32 ctx_size;
55 	__le32 unused;
56 };
57 
58 struct qcom_scm_mem_map_info {
59 	__le64 mem_addr;
60 	__le64 mem_size;
61 };
62 
63 static struct qcom_scm *__scm;
64 
65 static int qcom_scm_clk_enable(void)
66 {
67 	int ret;
68 
69 	ret = clk_prepare_enable(__scm->core_clk);
70 	if (ret)
71 		goto bail;
72 
73 	ret = clk_prepare_enable(__scm->iface_clk);
74 	if (ret)
75 		goto disable_core;
76 
77 	ret = clk_prepare_enable(__scm->bus_clk);
78 	if (ret)
79 		goto disable_iface;
80 
81 	return 0;
82 
83 disable_iface:
84 	clk_disable_unprepare(__scm->iface_clk);
85 disable_core:
86 	clk_disable_unprepare(__scm->core_clk);
87 bail:
88 	return ret;
89 }
90 
91 static void qcom_scm_clk_disable(void)
92 {
93 	clk_disable_unprepare(__scm->core_clk);
94 	clk_disable_unprepare(__scm->iface_clk);
95 	clk_disable_unprepare(__scm->bus_clk);
96 }
97 
98 /**
99  * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
100  * @entry: Entry point function for the cpus
101  * @cpus: The cpumask of cpus that will use the entry point
102  *
103  * Set the cold boot address of the cpus. Any cpu outside the supported
104  * range would be removed from the cpu present mask.
105  */
106 int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
107 {
108 	return __qcom_scm_set_cold_boot_addr(entry, cpus);
109 }
110 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
111 
112 /**
113  * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
114  * @entry: Entry point function for the cpus
115  * @cpus: The cpumask of cpus that will use the entry point
116  *
117  * Set the Linux entry point for the SCM to transfer control to when coming
118  * out of a power down. CPU power down may be executed on cpuidle or hotplug.
119  */
120 int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
121 {
122 	return __qcom_scm_set_warm_boot_addr(__scm->dev, entry, cpus);
123 }
124 EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
125 
126 /**
127  * qcom_scm_cpu_power_down() - Power down the cpu
128  * @flags - Flags to flush cache
129  *
130  * This is an end point to power down cpu. If there was a pending interrupt,
131  * the control would return from this function, otherwise, the cpu jumps to the
132  * warm boot entry point set for this cpu upon reset.
133  */
134 void qcom_scm_cpu_power_down(u32 flags)
135 {
136 	__qcom_scm_cpu_power_down(flags);
137 }
138 EXPORT_SYMBOL(qcom_scm_cpu_power_down);
139 
140 /**
141  * qcom_scm_hdcp_available() - Check if secure environment supports HDCP.
142  *
143  * Return true if HDCP is supported, false if not.
144  */
145 bool qcom_scm_hdcp_available(void)
146 {
147 	int ret = qcom_scm_clk_enable();
148 
149 	if (ret)
150 		return ret;
151 
152 	ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_HDCP,
153 						QCOM_SCM_CMD_HDCP);
154 
155 	qcom_scm_clk_disable();
156 
157 	return ret > 0 ? true : false;
158 }
159 EXPORT_SYMBOL(qcom_scm_hdcp_available);
160 
161 /**
162  * qcom_scm_hdcp_req() - Send HDCP request.
163  * @req: HDCP request array
164  * @req_cnt: HDCP request array count
165  * @resp: response buffer passed to SCM
166  *
167  * Write HDCP register(s) through SCM.
168  */
169 int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp)
170 {
171 	int ret = qcom_scm_clk_enable();
172 
173 	if (ret)
174 		return ret;
175 
176 	ret = __qcom_scm_hdcp_req(__scm->dev, req, req_cnt, resp);
177 	qcom_scm_clk_disable();
178 	return ret;
179 }
180 EXPORT_SYMBOL(qcom_scm_hdcp_req);
181 
182 /**
183  * qcom_scm_pas_supported() - Check if the peripheral authentication service is
184  *			      available for the given peripherial
185  * @peripheral:	peripheral id
186  *
187  * Returns true if PAS is supported for this peripheral, otherwise false.
188  */
189 bool qcom_scm_pas_supported(u32 peripheral)
190 {
191 	int ret;
192 
193 	ret = __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_PIL,
194 					   QCOM_SCM_PAS_IS_SUPPORTED_CMD);
195 	if (ret <= 0)
196 		return false;
197 
198 	return __qcom_scm_pas_supported(__scm->dev, peripheral);
199 }
200 EXPORT_SYMBOL(qcom_scm_pas_supported);
201 
202 /**
203  * qcom_scm_pas_init_image() - Initialize peripheral authentication service
204  *			       state machine for a given peripheral, using the
205  *			       metadata
206  * @peripheral: peripheral id
207  * @metadata:	pointer to memory containing ELF header, program header table
208  *		and optional blob of data used for authenticating the metadata
209  *		and the rest of the firmware
210  * @size:	size of the metadata
211  *
212  * Returns 0 on success.
213  */
214 int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size)
215 {
216 	dma_addr_t mdata_phys;
217 	void *mdata_buf;
218 	int ret;
219 
220 	/*
221 	 * During the scm call memory protection will be enabled for the meta
222 	 * data blob, so make sure it's physically contiguous, 4K aligned and
223 	 * non-cachable to avoid XPU violations.
224 	 */
225 	mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
226 				       GFP_KERNEL);
227 	if (!mdata_buf) {
228 		dev_err(__scm->dev, "Allocation of metadata buffer failed.\n");
229 		return -ENOMEM;
230 	}
231 	memcpy(mdata_buf, metadata, size);
232 
233 	ret = qcom_scm_clk_enable();
234 	if (ret)
235 		goto free_metadata;
236 
237 	ret = __qcom_scm_pas_init_image(__scm->dev, peripheral, mdata_phys);
238 
239 	qcom_scm_clk_disable();
240 
241 free_metadata:
242 	dma_free_coherent(__scm->dev, size, mdata_buf, mdata_phys);
243 
244 	return ret;
245 }
246 EXPORT_SYMBOL(qcom_scm_pas_init_image);
247 
248 /**
249  * qcom_scm_pas_mem_setup() - Prepare the memory related to a given peripheral
250  *			      for firmware loading
251  * @peripheral:	peripheral id
252  * @addr:	start address of memory area to prepare
253  * @size:	size of the memory area to prepare
254  *
255  * Returns 0 on success.
256  */
257 int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr, phys_addr_t size)
258 {
259 	int ret;
260 
261 	ret = qcom_scm_clk_enable();
262 	if (ret)
263 		return ret;
264 
265 	ret = __qcom_scm_pas_mem_setup(__scm->dev, peripheral, addr, size);
266 	qcom_scm_clk_disable();
267 
268 	return ret;
269 }
270 EXPORT_SYMBOL(qcom_scm_pas_mem_setup);
271 
272 /**
273  * qcom_scm_pas_auth_and_reset() - Authenticate the given peripheral firmware
274  *				   and reset the remote processor
275  * @peripheral:	peripheral id
276  *
277  * Return 0 on success.
278  */
279 int qcom_scm_pas_auth_and_reset(u32 peripheral)
280 {
281 	int ret;
282 
283 	ret = qcom_scm_clk_enable();
284 	if (ret)
285 		return ret;
286 
287 	ret = __qcom_scm_pas_auth_and_reset(__scm->dev, peripheral);
288 	qcom_scm_clk_disable();
289 
290 	return ret;
291 }
292 EXPORT_SYMBOL(qcom_scm_pas_auth_and_reset);
293 
294 /**
295  * qcom_scm_pas_shutdown() - Shut down the remote processor
296  * @peripheral: peripheral id
297  *
298  * Returns 0 on success.
299  */
300 int qcom_scm_pas_shutdown(u32 peripheral)
301 {
302 	int ret;
303 
304 	ret = qcom_scm_clk_enable();
305 	if (ret)
306 		return ret;
307 
308 	ret = __qcom_scm_pas_shutdown(__scm->dev, peripheral);
309 	qcom_scm_clk_disable();
310 
311 	return ret;
312 }
313 EXPORT_SYMBOL(qcom_scm_pas_shutdown);
314 
315 static int qcom_scm_pas_reset_assert(struct reset_controller_dev *rcdev,
316 				     unsigned long idx)
317 {
318 	if (idx != 0)
319 		return -EINVAL;
320 
321 	return __qcom_scm_pas_mss_reset(__scm->dev, 1);
322 }
323 
324 static int qcom_scm_pas_reset_deassert(struct reset_controller_dev *rcdev,
325 				       unsigned long idx)
326 {
327 	if (idx != 0)
328 		return -EINVAL;
329 
330 	return __qcom_scm_pas_mss_reset(__scm->dev, 0);
331 }
332 
333 static const struct reset_control_ops qcom_scm_pas_reset_ops = {
334 	.assert = qcom_scm_pas_reset_assert,
335 	.deassert = qcom_scm_pas_reset_deassert,
336 };
337 
338 int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare)
339 {
340 	return __qcom_scm_restore_sec_cfg(__scm->dev, device_id, spare);
341 }
342 EXPORT_SYMBOL(qcom_scm_restore_sec_cfg);
343 
344 int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size)
345 {
346 	return __qcom_scm_iommu_secure_ptbl_size(__scm->dev, spare, size);
347 }
348 EXPORT_SYMBOL(qcom_scm_iommu_secure_ptbl_size);
349 
350 int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare)
351 {
352 	return __qcom_scm_iommu_secure_ptbl_init(__scm->dev, addr, size, spare);
353 }
354 EXPORT_SYMBOL(qcom_scm_iommu_secure_ptbl_init);
355 
356 int qcom_scm_io_readl(phys_addr_t addr, unsigned int *val)
357 {
358 	return __qcom_scm_io_readl(__scm->dev, addr, val);
359 }
360 EXPORT_SYMBOL(qcom_scm_io_readl);
361 
362 int qcom_scm_io_writel(phys_addr_t addr, unsigned int val)
363 {
364 	return __qcom_scm_io_writel(__scm->dev, addr, val);
365 }
366 EXPORT_SYMBOL(qcom_scm_io_writel);
367 
368 static void qcom_scm_set_download_mode(bool enable)
369 {
370 	bool avail;
371 	int ret = 0;
372 
373 	avail = __qcom_scm_is_call_available(__scm->dev,
374 					     QCOM_SCM_SVC_BOOT,
375 					     QCOM_SCM_SET_DLOAD_MODE);
376 	if (avail) {
377 		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
378 	} else if (__scm->dload_mode_addr) {
379 		ret = __qcom_scm_io_writel(__scm->dev, __scm->dload_mode_addr,
380 					   enable ? QCOM_SCM_SET_DLOAD_MODE : 0);
381 	} else {
382 		dev_err(__scm->dev,
383 			"No available mechanism for setting download mode\n");
384 	}
385 
386 	if (ret)
387 		dev_err(__scm->dev, "failed to set download mode: %d\n", ret);
388 }
389 
390 static int qcom_scm_find_dload_address(struct device *dev, u64 *addr)
391 {
392 	struct device_node *tcsr;
393 	struct device_node *np = dev->of_node;
394 	struct resource res;
395 	u32 offset;
396 	int ret;
397 
398 	tcsr = of_parse_phandle(np, "qcom,dload-mode", 0);
399 	if (!tcsr)
400 		return 0;
401 
402 	ret = of_address_to_resource(tcsr, 0, &res);
403 	of_node_put(tcsr);
404 	if (ret)
405 		return ret;
406 
407 	ret = of_property_read_u32_index(np, "qcom,dload-mode", 1, &offset);
408 	if (ret < 0)
409 		return ret;
410 
411 	*addr = res.start + offset;
412 
413 	return 0;
414 }
415 
416 /**
417  * qcom_scm_is_available() - Checks if SCM is available
418  */
419 bool qcom_scm_is_available(void)
420 {
421 	return !!__scm;
422 }
423 EXPORT_SYMBOL(qcom_scm_is_available);
424 
425 int qcom_scm_set_remote_state(u32 state, u32 id)
426 {
427 	return __qcom_scm_set_remote_state(__scm->dev, state, id);
428 }
429 EXPORT_SYMBOL(qcom_scm_set_remote_state);
430 
431 /**
432  * qcom_scm_assign_mem() - Make a secure call to reassign memory ownership
433  * @mem_addr: mem region whose ownership need to be reassigned
434  * @mem_sz:   size of the region.
435  * @srcvm:    vmid for current set of owners, each set bit in
436  *            flag indicate a unique owner
437  * @newvm:    array having new owners and corrsponding permission
438  *            flags
439  * @dest_cnt: number of owners in next set.
440  *
441  * Return negative errno on failure, 0 on success, with @srcvm updated.
442  */
443 int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
444 			unsigned int *srcvm,
445 			struct qcom_scm_vmperm *newvm, int dest_cnt)
446 {
447 	struct qcom_scm_current_perm_info *destvm;
448 	struct qcom_scm_mem_map_info *mem_to_map;
449 	phys_addr_t mem_to_map_phys;
450 	phys_addr_t dest_phys;
451 	phys_addr_t ptr_phys;
452 	size_t mem_to_map_sz;
453 	size_t dest_sz;
454 	size_t src_sz;
455 	size_t ptr_sz;
456 	int next_vm;
457 	__le32 *src;
458 	void *ptr;
459 	int ret;
460 	int len;
461 	int i;
462 
463 	src_sz = hweight_long(*srcvm) * sizeof(*src);
464 	mem_to_map_sz = sizeof(*mem_to_map);
465 	dest_sz = dest_cnt * sizeof(*destvm);
466 	ptr_sz = ALIGN(src_sz, SZ_64) + ALIGN(mem_to_map_sz, SZ_64) +
467 			ALIGN(dest_sz, SZ_64);
468 
469 	ptr = dma_alloc_coherent(__scm->dev, ptr_sz, &ptr_phys, GFP_KERNEL);
470 	if (!ptr)
471 		return -ENOMEM;
472 
473 	/* Fill source vmid detail */
474 	src = ptr;
475 	len = hweight_long(*srcvm);
476 	for (i = 0; i < len; i++) {
477 		src[i] = cpu_to_le32(ffs(*srcvm) - 1);
478 		*srcvm ^= 1 << (ffs(*srcvm) - 1);
479 	}
480 
481 	/* Fill details of mem buff to map */
482 	mem_to_map = ptr + ALIGN(src_sz, SZ_64);
483 	mem_to_map_phys = ptr_phys + ALIGN(src_sz, SZ_64);
484 	mem_to_map[0].mem_addr = cpu_to_le64(mem_addr);
485 	mem_to_map[0].mem_size = cpu_to_le64(mem_sz);
486 
487 	next_vm = 0;
488 	/* Fill details of next vmid detail */
489 	destvm = ptr + ALIGN(mem_to_map_sz, SZ_64) + ALIGN(src_sz, SZ_64);
490 	dest_phys = ptr_phys + ALIGN(mem_to_map_sz, SZ_64) + ALIGN(src_sz, SZ_64);
491 	for (i = 0; i < dest_cnt; i++) {
492 		destvm[i].vmid = cpu_to_le32(newvm[i].vmid);
493 		destvm[i].perm = cpu_to_le32(newvm[i].perm);
494 		destvm[i].ctx = 0;
495 		destvm[i].ctx_size = 0;
496 		next_vm |= BIT(newvm[i].vmid);
497 	}
498 
499 	ret = __qcom_scm_assign_mem(__scm->dev, mem_to_map_phys, mem_to_map_sz,
500 				    ptr_phys, src_sz, dest_phys, dest_sz);
501 	dma_free_coherent(__scm->dev, ALIGN(ptr_sz, SZ_64), ptr, ptr_phys);
502 	if (ret) {
503 		dev_err(__scm->dev,
504 			"Assign memory protection call failed %d.\n", ret);
505 		return -EINVAL;
506 	}
507 
508 	*srcvm = next_vm;
509 	return 0;
510 }
511 EXPORT_SYMBOL(qcom_scm_assign_mem);
512 
513 static int qcom_scm_probe(struct platform_device *pdev)
514 {
515 	struct qcom_scm *scm;
516 	unsigned long clks;
517 	int ret;
518 
519 	scm = devm_kzalloc(&pdev->dev, sizeof(*scm), GFP_KERNEL);
520 	if (!scm)
521 		return -ENOMEM;
522 
523 	ret = qcom_scm_find_dload_address(&pdev->dev, &scm->dload_mode_addr);
524 	if (ret < 0)
525 		return ret;
526 
527 	clks = (unsigned long)of_device_get_match_data(&pdev->dev);
528 	if (clks & SCM_HAS_CORE_CLK) {
529 		scm->core_clk = devm_clk_get(&pdev->dev, "core");
530 		if (IS_ERR(scm->core_clk)) {
531 			if (PTR_ERR(scm->core_clk) != -EPROBE_DEFER)
532 				dev_err(&pdev->dev,
533 					"failed to acquire core clk\n");
534 			return PTR_ERR(scm->core_clk);
535 		}
536 	}
537 
538 	if (clks & SCM_HAS_IFACE_CLK) {
539 		scm->iface_clk = devm_clk_get(&pdev->dev, "iface");
540 		if (IS_ERR(scm->iface_clk)) {
541 			if (PTR_ERR(scm->iface_clk) != -EPROBE_DEFER)
542 				dev_err(&pdev->dev,
543 					"failed to acquire iface clk\n");
544 			return PTR_ERR(scm->iface_clk);
545 		}
546 	}
547 
548 	if (clks & SCM_HAS_BUS_CLK) {
549 		scm->bus_clk = devm_clk_get(&pdev->dev, "bus");
550 		if (IS_ERR(scm->bus_clk)) {
551 			if (PTR_ERR(scm->bus_clk) != -EPROBE_DEFER)
552 				dev_err(&pdev->dev,
553 					"failed to acquire bus clk\n");
554 			return PTR_ERR(scm->bus_clk);
555 		}
556 	}
557 
558 	scm->reset.ops = &qcom_scm_pas_reset_ops;
559 	scm->reset.nr_resets = 1;
560 	scm->reset.of_node = pdev->dev.of_node;
561 	ret = devm_reset_controller_register(&pdev->dev, &scm->reset);
562 	if (ret)
563 		return ret;
564 
565 	/* vote for max clk rate for highest performance */
566 	ret = clk_set_rate(scm->core_clk, INT_MAX);
567 	if (ret)
568 		return ret;
569 
570 	__scm = scm;
571 	__scm->dev = &pdev->dev;
572 
573 	__qcom_scm_init();
574 
575 	/*
576 	 * If requested enable "download mode", from this point on warmboot
577 	 * will cause the the boot stages to enter download mode, unless
578 	 * disabled below by a clean shutdown/reboot.
579 	 */
580 	if (download_mode)
581 		qcom_scm_set_download_mode(true);
582 
583 	return 0;
584 }
585 
586 static void qcom_scm_shutdown(struct platform_device *pdev)
587 {
588 	/* Clean shutdown, disable download mode to allow normal restart */
589 	if (download_mode)
590 		qcom_scm_set_download_mode(false);
591 }
592 
593 static const struct of_device_id qcom_scm_dt_match[] = {
594 	{ .compatible = "qcom,scm-apq8064",
595 	  /* FIXME: This should have .data = (void *) SCM_HAS_CORE_CLK */
596 	},
597 	{ .compatible = "qcom,scm-msm8660",
598 	  .data = (void *) SCM_HAS_CORE_CLK,
599 	},
600 	{ .compatible = "qcom,scm-msm8960",
601 	  .data = (void *) SCM_HAS_CORE_CLK,
602 	},
603 	{ .compatible = "qcom,scm-msm8996",
604 	  .data = NULL, /* no clocks */
605 	},
606 	{ .compatible = "qcom,scm",
607 	  .data = (void *)(SCM_HAS_CORE_CLK
608 			   | SCM_HAS_IFACE_CLK
609 			   | SCM_HAS_BUS_CLK),
610 	},
611 	{}
612 };
613 
614 static struct platform_driver qcom_scm_driver = {
615 	.driver = {
616 		.name	= "qcom_scm",
617 		.of_match_table = qcom_scm_dt_match,
618 	},
619 	.probe = qcom_scm_probe,
620 	.shutdown = qcom_scm_shutdown,
621 };
622 
623 static int __init qcom_scm_init(void)
624 {
625 	return platform_driver_register(&qcom_scm_driver);
626 }
627 subsys_initcall(qcom_scm_init);
628