xref: /linux/drivers/clk/imx/clk-scu.c (revision 1fd1dc41724319406b0aff221a352a400b0ddfc5)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2018-2021 NXP
4  *   Dong Aisheng <aisheng.dong@nxp.com>
5  */
6 
7 #include <dt-bindings/firmware/imx/rsrc.h>
8 #include <linux/arm-smccc.h>
9 #include <linux/bsearch.h>
10 #include <linux/clk-provider.h>
11 #include <linux/err.h>
12 #include <linux/of.h>
13 #include <linux/firmware/imx/svc/rm.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_domain.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/slab.h>
18 #include <xen/xen.h>
19 
20 #include "clk-scu.h"
21 
22 #define IMX_SIP_CPUFREQ			0xC2000001
23 #define IMX_SIP_SET_CPUFREQ		0x00
24 
25 static struct imx_sc_ipc *ccm_ipc_handle;
26 static struct device_node *pd_np;
27 static struct platform_driver imx_clk_scu_driver;
28 static const struct imx_clk_scu_rsrc_table *rsrc_table;
29 
30 struct imx_scu_clk_node {
31 	const char *name;
32 	u32 rsrc;
33 	u8 clk_type;
34 	const char * const *parents;
35 	int num_parents;
36 
37 	struct clk_hw *hw;
38 	struct list_head node;
39 };
40 
41 struct list_head imx_scu_clks[IMX_SC_R_LAST];
42 
43 /*
44  * struct clk_scu - Description of one SCU clock
45  * @hw: the common clk_hw
46  * @rsrc_id: resource ID of this SCU clock
47  * @clk_type: type of this clock resource
48  */
49 struct clk_scu {
50 	struct clk_hw hw;
51 	u16 rsrc_id;
52 	u8 clk_type;
53 
54 	/* for state save&restore */
55 	struct clk_hw *parent;
56 	u8 parent_index;
57 	bool is_enabled;
58 	u32 rate;
59 };
60 
61 /*
62  * struct clk_gpr_scu - Description of one SCU GPR clock
63  * @hw: the common clk_hw
64  * @rsrc_id: resource ID of this SCU clock
65  * @gpr_id: GPR ID index to control the divider
66  */
67 struct clk_gpr_scu {
68 	struct clk_hw hw;
69 	u16 rsrc_id;
70 	u8 gpr_id;
71 	u8 flags;
72 	bool gate_invert;
73 };
74 
75 #define to_clk_gpr_scu(_hw) container_of(_hw, struct clk_gpr_scu, hw)
76 
77 /*
78  * struct imx_sc_msg_req_set_clock_rate - clock set rate protocol
79  * @hdr: SCU protocol header
80  * @rate: rate to set
81  * @resource: clock resource to set rate
82  * @clk: clk type of this resource
83  *
84  * This structure describes the SCU protocol of clock rate set
85  */
86 struct imx_sc_msg_req_set_clock_rate {
87 	struct imx_sc_rpc_msg hdr;
88 	__le32 rate;
89 	__le16 resource;
90 	u8 clk;
91 } __packed __aligned(4);
92 
93 struct req_get_clock_rate {
94 	__le16 resource;
95 	u8 clk;
96 } __packed __aligned(4);
97 
98 struct resp_get_clock_rate {
99 	__le32 rate;
100 };
101 
102 /*
103  * struct imx_sc_msg_get_clock_rate - clock get rate protocol
104  * @hdr: SCU protocol header
105  * @req: get rate request protocol
106  * @resp: get rate response protocol
107  *
108  * This structure describes the SCU protocol of clock rate get
109  */
110 struct imx_sc_msg_get_clock_rate {
111 	struct imx_sc_rpc_msg hdr;
112 	union {
113 		struct req_get_clock_rate req;
114 		struct resp_get_clock_rate resp;
115 	} data;
116 };
117 
118 /*
119  * struct imx_sc_msg_get_clock_parent - clock get parent protocol
120  * @hdr: SCU protocol header
121  * @req: get parent request protocol
122  * @resp: get parent response protocol
123  *
124  * This structure describes the SCU protocol of clock get parent
125  */
126 struct imx_sc_msg_get_clock_parent {
127 	struct imx_sc_rpc_msg hdr;
128 	union {
129 		struct req_get_clock_parent {
130 			__le16 resource;
131 			u8 clk;
132 		} __packed __aligned(4) req;
133 		struct resp_get_clock_parent {
134 			u8 parent;
135 		} resp;
136 	} data;
137 };
138 
139 /*
140  * struct imx_sc_msg_set_clock_parent - clock set parent protocol
141  * @hdr: SCU protocol header
142  * @req: set parent request protocol
143  *
144  * This structure describes the SCU protocol of clock set parent
145  */
146 struct imx_sc_msg_set_clock_parent {
147 	struct imx_sc_rpc_msg hdr;
148 	__le16 resource;
149 	u8 clk;
150 	u8 parent;
151 } __packed;
152 
153 /*
154  * struct imx_sc_msg_req_clock_enable - clock gate protocol
155  * @hdr: SCU protocol header
156  * @resource: clock resource to gate
157  * @clk: clk type of this resource
158  * @enable: whether gate off the clock
159  * @autog: HW auto gate enable
160  *
161  * This structure describes the SCU protocol of clock gate
162  */
163 struct imx_sc_msg_req_clock_enable {
164 	struct imx_sc_rpc_msg hdr;
165 	__le16 resource;
166 	u8 clk;
167 	u8 enable;
168 	u8 autog;
169 } __packed __aligned(4);
170 
171 static inline struct clk_scu *to_clk_scu(struct clk_hw *hw)
172 {
173 	return container_of(hw, struct clk_scu, hw);
174 }
175 
176 static inline int imx_scu_clk_search_cmp(const void *rsrc, const void *rsrc_p)
177 {
178 	return *(u32 *)rsrc - *(u32 *)rsrc_p;
179 }
180 
181 static bool imx_scu_clk_is_valid(u32 rsrc_id)
182 {
183 	void *p;
184 
185 	if (!rsrc_table)
186 		return true;
187 
188 	p = bsearch(&rsrc_id, rsrc_table->rsrc, rsrc_table->num,
189 		    sizeof(rsrc_table->rsrc[0]), imx_scu_clk_search_cmp);
190 
191 	return p != NULL;
192 }
193 
194 int __init imx_clk_scu_module_init(void)
195 {
196 	return platform_driver_register(&imx_clk_scu_driver);
197 }
198 
199 void __exit imx_clk_scu_module_exit(void)
200 {
201 	return platform_driver_unregister(&imx_clk_scu_driver);
202 }
203 
204 int imx_clk_scu_init(struct device_node *np,
205 		     const struct imx_clk_scu_rsrc_table *data)
206 {
207 	u32 clk_cells;
208 	int ret, i;
209 
210 	ret = imx_scu_get_handle(&ccm_ipc_handle);
211 	if (ret)
212 		return ret;
213 
214 	of_property_read_u32(np, "#clock-cells", &clk_cells);
215 
216 	if (clk_cells == 2) {
217 		for (i = 0; i < IMX_SC_R_LAST; i++)
218 			INIT_LIST_HEAD(&imx_scu_clks[i]);
219 
220 		/* pd_np will be used to attach power domains later */
221 		pd_np = of_find_compatible_node(NULL, NULL, "fsl,scu-pd");
222 		if (!pd_np)
223 			return -EINVAL;
224 
225 		rsrc_table = data;
226 	}
227 
228 	return 0;
229 }
230 
231 /*
232  * clk_scu_recalc_rate - Get clock rate for a SCU clock
233  * @hw: clock to get rate for
234  * @parent_rate: parent rate provided by common clock framework, not used
235  *
236  * Gets the current clock rate of a SCU clock. Returns the current
237  * clock rate, or zero in failure.
238  */
239 static unsigned long clk_scu_recalc_rate(struct clk_hw *hw,
240 					 unsigned long parent_rate)
241 {
242 	struct clk_scu *clk = to_clk_scu(hw);
243 	struct imx_sc_msg_get_clock_rate msg;
244 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
245 	int ret;
246 
247 	hdr->ver = IMX_SC_RPC_VERSION;
248 	hdr->svc = IMX_SC_RPC_SVC_PM;
249 	hdr->func = IMX_SC_PM_FUNC_GET_CLOCK_RATE;
250 	hdr->size = 2;
251 
252 	msg.data.req.resource = cpu_to_le16(clk->rsrc_id);
253 	msg.data.req.clk = clk->clk_type;
254 
255 	ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
256 	if (ret) {
257 		pr_err("%s: failed to get clock rate %d\n",
258 		       clk_hw_get_name(hw), ret);
259 		return 0;
260 	}
261 
262 	return le32_to_cpu(msg.data.resp.rate);
263 }
264 
265 /*
266  * clk_scu_determine_rate - Returns the closest rate for a SCU clock
267  * @hw: clock to round rate for
268  * @req: clock rate request
269  *
270  * Returns 0 on success, a negative error on failure
271  */
272 static int clk_scu_determine_rate(struct clk_hw *hw,
273 				  struct clk_rate_request *req)
274 {
275 	/*
276 	 * Assume we support all the requested rate and let the SCU firmware
277 	 * to handle the left work
278 	 */
279 	return 0;
280 }
281 
282 static int clk_scu_atf_set_cpu_rate(struct clk_hw *hw, unsigned long rate,
283 				    unsigned long parent_rate)
284 {
285 	struct clk_scu *clk = to_clk_scu(hw);
286 	struct arm_smccc_res res;
287 	unsigned long cluster_id;
288 
289 	if (clk->rsrc_id == IMX_SC_R_A35 || clk->rsrc_id == IMX_SC_R_A53)
290 		cluster_id = 0;
291 	else if (clk->rsrc_id == IMX_SC_R_A72)
292 		cluster_id = 1;
293 	else
294 		return -EINVAL;
295 
296 	/* CPU frequency scaling can ONLY be done by ARM-Trusted-Firmware */
297 	arm_smccc_smc(IMX_SIP_CPUFREQ, IMX_SIP_SET_CPUFREQ,
298 		      cluster_id, rate, 0, 0, 0, 0, &res);
299 
300 	return 0;
301 }
302 
303 /*
304  * clk_scu_set_rate - Set rate for a SCU clock
305  * @hw: clock to change rate for
306  * @rate: target rate for the clock
307  * @parent_rate: rate of the clock parent, not used for SCU clocks
308  *
309  * Sets a clock frequency for a SCU clock. Returns the SCU
310  * protocol status.
311  */
312 static int clk_scu_set_rate(struct clk_hw *hw, unsigned long rate,
313 			    unsigned long parent_rate)
314 {
315 	struct clk_scu *clk = to_clk_scu(hw);
316 	struct imx_sc_msg_req_set_clock_rate msg;
317 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
318 
319 	hdr->ver = IMX_SC_RPC_VERSION;
320 	hdr->svc = IMX_SC_RPC_SVC_PM;
321 	hdr->func = IMX_SC_PM_FUNC_SET_CLOCK_RATE;
322 	hdr->size = 3;
323 
324 	msg.rate = cpu_to_le32(rate);
325 	msg.resource = cpu_to_le16(clk->rsrc_id);
326 	msg.clk = clk->clk_type;
327 
328 	return imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
329 }
330 
331 static u8 clk_scu_get_parent(struct clk_hw *hw)
332 {
333 	struct clk_scu *clk = to_clk_scu(hw);
334 	struct imx_sc_msg_get_clock_parent msg;
335 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
336 	int ret;
337 
338 	hdr->ver = IMX_SC_RPC_VERSION;
339 	hdr->svc = IMX_SC_RPC_SVC_PM;
340 	hdr->func = IMX_SC_PM_FUNC_GET_CLOCK_PARENT;
341 	hdr->size = 2;
342 
343 	msg.data.req.resource = cpu_to_le16(clk->rsrc_id);
344 	msg.data.req.clk = clk->clk_type;
345 
346 	ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
347 	if (ret) {
348 		pr_err("%s: failed to get clock parent %d\n",
349 		       clk_hw_get_name(hw), ret);
350 		return 0;
351 	}
352 
353 	clk->parent_index = msg.data.resp.parent;
354 
355 	return msg.data.resp.parent;
356 }
357 
358 static int clk_scu_set_parent(struct clk_hw *hw, u8 index)
359 {
360 	struct clk_scu *clk = to_clk_scu(hw);
361 	struct imx_sc_msg_set_clock_parent msg;
362 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
363 	int ret;
364 
365 	hdr->ver = IMX_SC_RPC_VERSION;
366 	hdr->svc = IMX_SC_RPC_SVC_PM;
367 	hdr->func = IMX_SC_PM_FUNC_SET_CLOCK_PARENT;
368 	hdr->size = 2;
369 
370 	msg.resource = cpu_to_le16(clk->rsrc_id);
371 	msg.clk = clk->clk_type;
372 	msg.parent = index;
373 
374 	ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
375 	if (ret) {
376 		pr_err("%s: failed to set clock parent %d\n",
377 		       clk_hw_get_name(hw), ret);
378 		return ret;
379 	}
380 
381 	clk->parent_index = index;
382 
383 	return 0;
384 }
385 
386 static int sc_pm_clock_enable(struct imx_sc_ipc *ipc, u16 resource,
387 			      u8 clk, bool enable, bool autog)
388 {
389 	struct imx_sc_msg_req_clock_enable msg;
390 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
391 
392 	hdr->ver = IMX_SC_RPC_VERSION;
393 	hdr->svc = IMX_SC_RPC_SVC_PM;
394 	hdr->func = IMX_SC_PM_FUNC_CLOCK_ENABLE;
395 	hdr->size = 3;
396 
397 	msg.resource = cpu_to_le16(resource);
398 	msg.clk = clk;
399 	msg.enable = enable;
400 	msg.autog = autog;
401 
402 	return imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
403 }
404 
405 /*
406  * clk_scu_prepare - Enable a SCU clock
407  * @hw: clock to enable
408  *
409  * Enable the clock at the DSC slice level
410  */
411 static int clk_scu_prepare(struct clk_hw *hw)
412 {
413 	struct clk_scu *clk = to_clk_scu(hw);
414 
415 	return sc_pm_clock_enable(ccm_ipc_handle, clk->rsrc_id,
416 				  clk->clk_type, true, false);
417 }
418 
419 /*
420  * clk_scu_unprepare - Disable a SCU clock
421  * @hw: clock to enable
422  *
423  * Disable the clock at the DSC slice level
424  */
425 static void clk_scu_unprepare(struct clk_hw *hw)
426 {
427 	struct clk_scu *clk = to_clk_scu(hw);
428 	int ret;
429 
430 	ret = sc_pm_clock_enable(ccm_ipc_handle, clk->rsrc_id,
431 				 clk->clk_type, false, false);
432 	if (ret)
433 		pr_warn("%s: clk unprepare failed %d\n", clk_hw_get_name(hw),
434 			ret);
435 }
436 
437 static const struct clk_ops clk_scu_ops = {
438 	.recalc_rate = clk_scu_recalc_rate,
439 	.determine_rate = clk_scu_determine_rate,
440 	.set_rate = clk_scu_set_rate,
441 	.get_parent = clk_scu_get_parent,
442 	.set_parent = clk_scu_set_parent,
443 	.prepare = clk_scu_prepare,
444 	.unprepare = clk_scu_unprepare,
445 };
446 
447 static const struct clk_ops clk_scu_cpu_ops = {
448 	.recalc_rate = clk_scu_recalc_rate,
449 	.determine_rate = clk_scu_determine_rate,
450 	.set_rate = clk_scu_atf_set_cpu_rate,
451 	.prepare = clk_scu_prepare,
452 	.unprepare = clk_scu_unprepare,
453 };
454 
455 static const struct clk_ops clk_scu_pi_ops = {
456 	.recalc_rate = clk_scu_recalc_rate,
457 	.determine_rate = clk_scu_determine_rate,
458 	.set_rate    = clk_scu_set_rate,
459 };
460 
461 struct clk_hw *__imx_clk_scu(struct device *dev, const char *name,
462 			     const char * const *parents, int num_parents,
463 			     u32 rsrc_id, u8 clk_type)
464 {
465 	struct clk_init_data init;
466 	struct clk_scu *clk;
467 	struct clk_hw *hw;
468 	int ret;
469 
470 	clk = kzalloc_obj(*clk);
471 	if (!clk)
472 		return ERR_PTR(-ENOMEM);
473 
474 	clk->rsrc_id = rsrc_id;
475 	clk->clk_type = clk_type;
476 
477 	init.name = name;
478 	init.ops = &clk_scu_ops;
479 	if (rsrc_id == IMX_SC_R_A35 || rsrc_id == IMX_SC_R_A53 || rsrc_id == IMX_SC_R_A72)
480 		init.ops = &clk_scu_cpu_ops;
481 	else if (rsrc_id == IMX_SC_R_PI_0_PLL)
482 		init.ops = &clk_scu_pi_ops;
483 	else
484 		init.ops = &clk_scu_ops;
485 	init.parent_names = parents;
486 	init.num_parents = num_parents;
487 
488 	/*
489 	 * Note on MX8, the clocks are tightly coupled with power domain
490 	 * that once the power domain is off, the clock status may be
491 	 * lost. So we make it NOCACHE to let user to retrieve the real
492 	 * clock status from HW instead of using the possible invalid
493 	 * cached rate.
494 	 */
495 	init.flags = CLK_GET_RATE_NOCACHE;
496 	clk->hw.init = &init;
497 
498 	hw = &clk->hw;
499 	ret = clk_hw_register(dev, hw);
500 	if (ret) {
501 		kfree(clk);
502 		hw = ERR_PTR(ret);
503 		return hw;
504 	}
505 
506 	if (dev)
507 		dev_set_drvdata(dev, clk);
508 
509 	return hw;
510 }
511 
512 struct clk_hw *imx_scu_of_clk_src_get(struct of_phandle_args *clkspec,
513 				      void *data)
514 {
515 	unsigned int rsrc = clkspec->args[0];
516 	unsigned int idx = clkspec->args[1];
517 	struct list_head *scu_clks = data;
518 	struct imx_scu_clk_node *clk;
519 
520 	list_for_each_entry(clk, &scu_clks[rsrc], node) {
521 		if (clk->clk_type == idx)
522 			return clk->hw;
523 	}
524 
525 	return ERR_PTR(-ENODEV);
526 }
527 
528 static int imx_clk_scu_probe(struct platform_device *pdev)
529 {
530 	struct device *dev = &pdev->dev;
531 	struct imx_scu_clk_node *clk = dev_get_platdata(dev);
532 	struct clk_hw *hw;
533 	int ret;
534 
535 	if (!((clk->rsrc == IMX_SC_R_A35) || (clk->rsrc == IMX_SC_R_A53) ||
536 	    (clk->rsrc == IMX_SC_R_A72))) {
537 		pm_runtime_set_suspended(dev);
538 		pm_runtime_set_autosuspend_delay(dev, 50);
539 		pm_runtime_use_autosuspend(&pdev->dev);
540 		pm_runtime_enable(dev);
541 
542 		ret = pm_runtime_resume_and_get(dev);
543 		if (ret) {
544 			pm_genpd_remove_device(dev);
545 			pm_runtime_disable(dev);
546 			return ret;
547 		}
548 	}
549 
550 	hw = __imx_clk_scu(dev, clk->name, clk->parents, clk->num_parents,
551 			   clk->rsrc, clk->clk_type);
552 	if (IS_ERR(hw)) {
553 		pm_runtime_disable(dev);
554 		return PTR_ERR(hw);
555 	}
556 
557 	clk->hw = hw;
558 	list_add_tail(&clk->node, &imx_scu_clks[clk->rsrc]);
559 
560 	if (!((clk->rsrc == IMX_SC_R_A35) || (clk->rsrc == IMX_SC_R_A53) ||
561 	    (clk->rsrc == IMX_SC_R_A72))) {
562 		pm_runtime_put_autosuspend(&pdev->dev);
563 	}
564 
565 	dev_dbg(dev, "register SCU clock rsrc:%d type:%d\n", clk->rsrc,
566 		clk->clk_type);
567 
568 	return 0;
569 }
570 
571 static int __maybe_unused imx_clk_scu_suspend(struct device *dev)
572 {
573 	struct clk_scu *clk = dev_get_drvdata(dev);
574 	u32 rsrc_id = clk->rsrc_id;
575 
576 	if ((rsrc_id == IMX_SC_R_A35) || (rsrc_id == IMX_SC_R_A53) ||
577 	    (rsrc_id == IMX_SC_R_A72))
578 		return 0;
579 
580 	clk->parent = clk_hw_get_parent(&clk->hw);
581 
582 	/* DC SS needs to handle bypass clock using non-cached clock rate */
583 	if (clk->rsrc_id == IMX_SC_R_DC_0_VIDEO0 ||
584 		clk->rsrc_id == IMX_SC_R_DC_0_VIDEO1 ||
585 		clk->rsrc_id == IMX_SC_R_DC_1_VIDEO0 ||
586 		clk->rsrc_id == IMX_SC_R_DC_1_VIDEO1)
587 		clk->rate = clk_scu_recalc_rate(&clk->hw, 0);
588 	else
589 		clk->rate = clk_hw_get_rate(&clk->hw);
590 	clk->is_enabled = clk_hw_is_prepared(&clk->hw);
591 
592 	if (clk->parent)
593 		dev_dbg(dev, "save parent %s idx %u\n", clk_hw_get_name(clk->parent),
594 			clk->parent_index);
595 
596 	if (clk->rate)
597 		dev_dbg(dev, "save rate %d\n", clk->rate);
598 
599 	if (clk->is_enabled)
600 		dev_dbg(dev, "save enabled state\n");
601 
602 	return 0;
603 }
604 
605 static int __maybe_unused imx_clk_scu_resume(struct device *dev)
606 {
607 	struct clk_scu *clk = dev_get_drvdata(dev);
608 	u32 rsrc_id = clk->rsrc_id;
609 	int ret = 0;
610 
611 	if ((rsrc_id == IMX_SC_R_A35) || (rsrc_id == IMX_SC_R_A53) ||
612 	    (rsrc_id == IMX_SC_R_A72))
613 		return 0;
614 
615 	if (clk->parent) {
616 		ret = clk_scu_set_parent(&clk->hw, clk->parent_index);
617 		dev_dbg(dev, "restore parent %s idx %u %s\n",
618 			clk_hw_get_name(clk->parent),
619 			clk->parent_index, !ret ? "success" : "failed");
620 	}
621 
622 	if (clk->rate) {
623 		ret = clk_scu_set_rate(&clk->hw, clk->rate, 0);
624 		dev_dbg(dev, "restore rate %d %s\n", clk->rate,
625 			!ret ? "success" : "failed");
626 	}
627 
628 	if (clk->is_enabled && rsrc_id != IMX_SC_R_PI_0_PLL) {
629 		ret = clk_scu_prepare(&clk->hw);
630 		dev_dbg(dev, "restore enabled state %s\n",
631 			!ret ? "success" : "failed");
632 	}
633 
634 	return ret;
635 }
636 
637 static const struct dev_pm_ops imx_clk_scu_pm_ops = {
638 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_clk_scu_suspend,
639 				      imx_clk_scu_resume)
640 };
641 
642 static struct platform_driver imx_clk_scu_driver = {
643 	.driver = {
644 		.name = "imx-scu-clk",
645 		.suppress_bind_attrs = true,
646 		.pm = &imx_clk_scu_pm_ops,
647 	},
648 	.probe = imx_clk_scu_probe,
649 };
650 
651 static int imx_clk_scu_attach_pd(struct device *dev, u32 rsrc_id)
652 {
653 	struct of_phandle_args genpdspec = {
654 		.np = pd_np,
655 		.args_count = 1,
656 		.args[0] = rsrc_id,
657 	};
658 
659 	if (rsrc_id == IMX_SC_R_A35 || rsrc_id == IMX_SC_R_A53 ||
660 	    rsrc_id == IMX_SC_R_A72)
661 		return 0;
662 
663 	return of_genpd_add_device(&genpdspec, dev);
664 }
665 
666 static bool imx_clk_is_resource_owned(u32 rsrc)
667 {
668 	/*
669 	 * A-core resources are special. SCFW reports they are not "owned" by
670 	 * current partition but linux can still adjust them for cpufreq.
671 	 */
672 	if (rsrc == IMX_SC_R_A53 || rsrc == IMX_SC_R_A72 || rsrc == IMX_SC_R_A35)
673 		return true;
674 
675 	return imx_sc_rm_is_resource_owned(ccm_ipc_handle, rsrc);
676 }
677 
678 struct clk_hw *imx_clk_scu_alloc_dev(const char *name,
679 				     const char * const *parents,
680 				     int num_parents, u32 rsrc_id, u8 clk_type)
681 {
682 	struct imx_scu_clk_node clk = {
683 		.name = name,
684 		.rsrc = rsrc_id,
685 		.clk_type = clk_type,
686 		.parents = parents,
687 		.num_parents = num_parents,
688 	};
689 	struct platform_device *pdev;
690 	int ret;
691 
692 	if (!imx_scu_clk_is_valid(rsrc_id))
693 		return ERR_PTR(-EINVAL);
694 
695 	if (!imx_clk_is_resource_owned(rsrc_id))
696 		return NULL;
697 
698 	pdev = platform_device_alloc(name, PLATFORM_DEVID_NONE);
699 	if (!pdev) {
700 		pr_err("%s: failed to allocate scu clk dev rsrc %d type %d\n",
701 		       name, rsrc_id, clk_type);
702 		return ERR_PTR(-ENOMEM);
703 	}
704 
705 	ret = platform_device_add_data(pdev, &clk, sizeof(clk));
706 	if (ret)
707 		goto put_device;
708 
709 	ret = driver_set_override(&pdev->dev, &pdev->driver_override,
710 				  "imx-scu-clk", strlen("imx-scu-clk"));
711 	if (ret)
712 		goto put_device;
713 
714 	ret = imx_clk_scu_attach_pd(&pdev->dev, rsrc_id);
715 	if (ret)
716 		pr_warn("%s: failed to attached the power domain %d\n",
717 			name, ret);
718 
719 	ret = platform_device_add(pdev);
720 	if (ret)
721 		goto put_device;
722 
723 	/* For API backwards compatibility, simply return NULL for success */
724 	return NULL;
725 
726 put_device:
727 	platform_device_put(pdev);
728 	return ERR_PTR(ret);
729 }
730 
731 void imx_clk_scu_unregister(void)
732 {
733 	struct imx_scu_clk_node *clk, *n;
734 	int i;
735 
736 	for (i = 0; i < IMX_SC_R_LAST; i++) {
737 		list_for_each_entry_safe(clk, n, &imx_scu_clks[i], node) {
738 			clk_hw_unregister(clk->hw);
739 			kfree(clk);
740 		}
741 	}
742 }
743 
744 static unsigned long clk_gpr_div_scu_recalc_rate(struct clk_hw *hw,
745 						 unsigned long parent_rate)
746 {
747 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
748 	unsigned long rate = 0;
749 	u32 val;
750 	int err;
751 
752 	err = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
753 				      clk->gpr_id, &val);
754 
755 	rate  = val ? parent_rate / 2 : parent_rate;
756 
757 	return err ? 0 : rate;
758 }
759 
760 static int clk_gpr_div_scu_determine_rate(struct clk_hw *hw,
761 					  struct clk_rate_request *req)
762 {
763 	if (req->rate < req->best_parent_rate)
764 		req->rate = req->best_parent_rate / 2;
765 	else
766 		req->rate = req->best_parent_rate;
767 
768 	return 0;
769 }
770 
771 static int clk_gpr_div_scu_set_rate(struct clk_hw *hw, unsigned long rate,
772 				    unsigned long parent_rate)
773 {
774 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
775 	uint32_t val;
776 	int err;
777 
778 	val = (rate < parent_rate) ? 1 : 0;
779 	err = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
780 				      clk->gpr_id, val);
781 
782 	return err ? -EINVAL : 0;
783 }
784 
785 static const struct clk_ops clk_gpr_div_scu_ops = {
786 	.recalc_rate = clk_gpr_div_scu_recalc_rate,
787 	.determine_rate = clk_gpr_div_scu_determine_rate,
788 	.set_rate = clk_gpr_div_scu_set_rate,
789 };
790 
791 static u8 clk_gpr_mux_scu_get_parent(struct clk_hw *hw)
792 {
793 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
794 	u32 val = 0;
795 
796 	imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
797 				clk->gpr_id, &val);
798 
799 	return (u8)val;
800 }
801 
802 static int clk_gpr_mux_scu_set_parent(struct clk_hw *hw, u8 index)
803 {
804 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
805 
806 	return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
807 				       clk->gpr_id, index);
808 }
809 
810 static const struct clk_ops clk_gpr_mux_scu_ops = {
811 	.determine_rate = clk_hw_determine_rate_no_reparent,
812 	.get_parent = clk_gpr_mux_scu_get_parent,
813 	.set_parent = clk_gpr_mux_scu_set_parent,
814 };
815 
816 static int clk_gpr_gate_scu_prepare(struct clk_hw *hw)
817 {
818 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
819 
820 	return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
821 				       clk->gpr_id, !clk->gate_invert);
822 }
823 
824 static void clk_gpr_gate_scu_unprepare(struct clk_hw *hw)
825 {
826 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
827 	int ret;
828 
829 	ret = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
830 				      clk->gpr_id, clk->gate_invert);
831 	if (ret)
832 		pr_err("%s: clk unprepare failed %d\n", clk_hw_get_name(hw),
833 		       ret);
834 }
835 
836 static int clk_gpr_gate_scu_is_prepared(struct clk_hw *hw)
837 {
838 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
839 	int ret;
840 	u32 val;
841 
842 	ret = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
843 				      clk->gpr_id, &val);
844 	if (ret)
845 		return ret;
846 
847 	return clk->gate_invert ? !val : val;
848 }
849 
850 static const struct clk_ops clk_gpr_gate_scu_ops = {
851 	.prepare = clk_gpr_gate_scu_prepare,
852 	.unprepare = clk_gpr_gate_scu_unprepare,
853 	.is_prepared = clk_gpr_gate_scu_is_prepared,
854 };
855 
856 struct clk_hw *__imx_clk_gpr_scu(const char *name, const char * const *parent_name,
857 				 int num_parents, u32 rsrc_id, u8 gpr_id, u8 flags,
858 				 bool invert)
859 {
860 	struct imx_scu_clk_node *clk_node;
861 	struct clk_gpr_scu *clk;
862 	struct clk_hw *hw;
863 	struct clk_init_data init;
864 	int ret;
865 
866 	if (rsrc_id >= IMX_SC_R_LAST || gpr_id >= IMX_SC_C_LAST)
867 		return ERR_PTR(-EINVAL);
868 
869 	clk_node = kzalloc_obj(*clk_node);
870 	if (!clk_node)
871 		return ERR_PTR(-ENOMEM);
872 
873 	if (!imx_scu_clk_is_valid(rsrc_id)) {
874 		kfree(clk_node);
875 		return ERR_PTR(-EINVAL);
876 	}
877 
878 	if (!imx_clk_is_resource_owned(rsrc_id)) {
879 		kfree(clk_node);
880 		return NULL;
881 	}
882 
883 	clk = kzalloc_obj(*clk);
884 	if (!clk) {
885 		kfree(clk_node);
886 		return ERR_PTR(-ENOMEM);
887 	}
888 
889 	clk->rsrc_id = rsrc_id;
890 	clk->gpr_id = gpr_id;
891 	clk->flags = flags;
892 	clk->gate_invert = invert;
893 
894 	if (flags & IMX_SCU_GPR_CLK_GATE)
895 		init.ops = &clk_gpr_gate_scu_ops;
896 
897 	if (flags & IMX_SCU_GPR_CLK_DIV)
898 		init.ops = &clk_gpr_div_scu_ops;
899 
900 	if (flags & IMX_SCU_GPR_CLK_MUX)
901 		init.ops = &clk_gpr_mux_scu_ops;
902 
903 	init.flags = 0;
904 	init.name = name;
905 	init.parent_names = parent_name;
906 	init.num_parents = num_parents;
907 
908 	clk->hw.init = &init;
909 
910 	hw = &clk->hw;
911 	ret = clk_hw_register(NULL, hw);
912 	if (ret) {
913 		kfree(clk);
914 		kfree(clk_node);
915 		hw = ERR_PTR(ret);
916 	} else {
917 		clk_node->hw = hw;
918 		clk_node->clk_type = gpr_id;
919 		list_add_tail(&clk_node->node, &imx_scu_clks[rsrc_id]);
920 	}
921 
922 	return hw;
923 }
924