xref: /linux/drivers/clk/imx/clk-scu.c (revision 0da908c291070d89482f6211dbe81d4d43c3f7cb)
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_platform.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_domain.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/slab.h>
17 
18 #include "clk-scu.h"
19 
20 #define IMX_SIP_CPUFREQ			0xC2000001
21 #define IMX_SIP_SET_CPUFREQ		0x00
22 
23 static struct imx_sc_ipc *ccm_ipc_handle;
24 static struct device_node *pd_np;
25 static struct platform_driver imx_clk_scu_driver;
26 static const struct imx_clk_scu_rsrc_table *rsrc_table;
27 
28 struct imx_scu_clk_node {
29 	const char *name;
30 	u32 rsrc;
31 	u8 clk_type;
32 	const char * const *parents;
33 	int num_parents;
34 
35 	struct clk_hw *hw;
36 	struct list_head node;
37 };
38 
39 struct list_head imx_scu_clks[IMX_SC_R_LAST];
40 
41 /*
42  * struct clk_scu - Description of one SCU clock
43  * @hw: the common clk_hw
44  * @rsrc_id: resource ID of this SCU clock
45  * @clk_type: type of this clock resource
46  */
47 struct clk_scu {
48 	struct clk_hw hw;
49 	u16 rsrc_id;
50 	u8 clk_type;
51 
52 	/* for state save&restore */
53 	struct clk_hw *parent;
54 	u8 parent_index;
55 	bool is_enabled;
56 	u32 rate;
57 };
58 
59 /*
60  * struct clk_gpr_scu - Description of one SCU GPR clock
61  * @hw: the common clk_hw
62  * @rsrc_id: resource ID of this SCU clock
63  * @gpr_id: GPR ID index to control the divider
64  */
65 struct clk_gpr_scu {
66 	struct clk_hw hw;
67 	u16 rsrc_id;
68 	u8 gpr_id;
69 	u8 flags;
70 	bool gate_invert;
71 };
72 
73 #define to_clk_gpr_scu(_hw) container_of(_hw, struct clk_gpr_scu, hw)
74 
75 /*
76  * struct imx_sc_msg_req_set_clock_rate - clock set rate protocol
77  * @hdr: SCU protocol header
78  * @rate: rate to set
79  * @resource: clock resource to set rate
80  * @clk: clk type of this resource
81  *
82  * This structure describes the SCU protocol of clock rate set
83  */
84 struct imx_sc_msg_req_set_clock_rate {
85 	struct imx_sc_rpc_msg hdr;
86 	__le32 rate;
87 	__le16 resource;
88 	u8 clk;
89 } __packed __aligned(4);
90 
91 struct req_get_clock_rate {
92 	__le16 resource;
93 	u8 clk;
94 } __packed __aligned(4);
95 
96 struct resp_get_clock_rate {
97 	__le32 rate;
98 };
99 
100 /*
101  * struct imx_sc_msg_get_clock_rate - clock get rate protocol
102  * @hdr: SCU protocol header
103  * @req: get rate request protocol
104  * @resp: get rate response protocol
105  *
106  * This structure describes the SCU protocol of clock rate get
107  */
108 struct imx_sc_msg_get_clock_rate {
109 	struct imx_sc_rpc_msg hdr;
110 	union {
111 		struct req_get_clock_rate req;
112 		struct resp_get_clock_rate resp;
113 	} data;
114 };
115 
116 /*
117  * struct imx_sc_msg_get_clock_parent - clock get parent protocol
118  * @hdr: SCU protocol header
119  * @req: get parent request protocol
120  * @resp: get parent response protocol
121  *
122  * This structure describes the SCU protocol of clock get parent
123  */
124 struct imx_sc_msg_get_clock_parent {
125 	struct imx_sc_rpc_msg hdr;
126 	union {
127 		struct req_get_clock_parent {
128 			__le16 resource;
129 			u8 clk;
130 		} __packed __aligned(4) req;
131 		struct resp_get_clock_parent {
132 			u8 parent;
133 		} resp;
134 	} data;
135 };
136 
137 /*
138  * struct imx_sc_msg_set_clock_parent - clock set parent protocol
139  * @hdr: SCU protocol header
140  * @req: set parent request protocol
141  *
142  * This structure describes the SCU protocol of clock set parent
143  */
144 struct imx_sc_msg_set_clock_parent {
145 	struct imx_sc_rpc_msg hdr;
146 	__le16 resource;
147 	u8 clk;
148 	u8 parent;
149 } __packed;
150 
151 /*
152  * struct imx_sc_msg_req_clock_enable - clock gate protocol
153  * @hdr: SCU protocol header
154  * @resource: clock resource to gate
155  * @clk: clk type of this resource
156  * @enable: whether gate off the clock
157  * @autog: HW auto gate enable
158  *
159  * This structure describes the SCU protocol of clock gate
160  */
161 struct imx_sc_msg_req_clock_enable {
162 	struct imx_sc_rpc_msg hdr;
163 	__le16 resource;
164 	u8 clk;
165 	u8 enable;
166 	u8 autog;
167 } __packed __aligned(4);
168 
169 static inline struct clk_scu *to_clk_scu(struct clk_hw *hw)
170 {
171 	return container_of(hw, struct clk_scu, hw);
172 }
173 
174 static inline int imx_scu_clk_search_cmp(const void *rsrc, const void *rsrc_p)
175 {
176 	return *(u32 *)rsrc - *(u32 *)rsrc_p;
177 }
178 
179 static bool imx_scu_clk_is_valid(u32 rsrc_id)
180 {
181 	void *p;
182 
183 	if (!rsrc_table)
184 		return true;
185 
186 	p = bsearch(&rsrc_id, rsrc_table->rsrc, rsrc_table->num,
187 		    sizeof(rsrc_table->rsrc[0]), imx_scu_clk_search_cmp);
188 
189 	return p != NULL;
190 }
191 
192 int imx_clk_scu_init(struct device_node *np,
193 		     const struct imx_clk_scu_rsrc_table *data)
194 {
195 	u32 clk_cells;
196 	int ret, i;
197 
198 	ret = imx_scu_get_handle(&ccm_ipc_handle);
199 	if (ret)
200 		return ret;
201 
202 	of_property_read_u32(np, "#clock-cells", &clk_cells);
203 
204 	if (clk_cells == 2) {
205 		for (i = 0; i < IMX_SC_R_LAST; i++)
206 			INIT_LIST_HEAD(&imx_scu_clks[i]);
207 
208 		/* pd_np will be used to attach power domains later */
209 		pd_np = of_find_compatible_node(NULL, NULL, "fsl,scu-pd");
210 		if (!pd_np)
211 			return -EINVAL;
212 
213 		rsrc_table = data;
214 	}
215 
216 	return platform_driver_register(&imx_clk_scu_driver);
217 }
218 
219 /*
220  * clk_scu_recalc_rate - Get clock rate for a SCU clock
221  * @hw: clock to get rate for
222  * @parent_rate: parent rate provided by common clock framework, not used
223  *
224  * Gets the current clock rate of a SCU clock. Returns the current
225  * clock rate, or zero in failure.
226  */
227 static unsigned long clk_scu_recalc_rate(struct clk_hw *hw,
228 					 unsigned long parent_rate)
229 {
230 	struct clk_scu *clk = to_clk_scu(hw);
231 	struct imx_sc_msg_get_clock_rate msg;
232 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
233 	int ret;
234 
235 	hdr->ver = IMX_SC_RPC_VERSION;
236 	hdr->svc = IMX_SC_RPC_SVC_PM;
237 	hdr->func = IMX_SC_PM_FUNC_GET_CLOCK_RATE;
238 	hdr->size = 2;
239 
240 	msg.data.req.resource = cpu_to_le16(clk->rsrc_id);
241 	msg.data.req.clk = clk->clk_type;
242 
243 	ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
244 	if (ret) {
245 		pr_err("%s: failed to get clock rate %d\n",
246 		       clk_hw_get_name(hw), ret);
247 		return 0;
248 	}
249 
250 	return le32_to_cpu(msg.data.resp.rate);
251 }
252 
253 /*
254  * clk_scu_round_rate - Round clock rate for a SCU clock
255  * @hw: clock to round rate for
256  * @rate: rate to round
257  * @parent_rate: parent rate provided by common clock framework, not used
258  *
259  * Returns the current clock rate, or zero in failure.
260  */
261 static long clk_scu_round_rate(struct clk_hw *hw, unsigned long rate,
262 			       unsigned long *parent_rate)
263 {
264 	/*
265 	 * Assume we support all the requested rate and let the SCU firmware
266 	 * to handle the left work
267 	 */
268 	return rate;
269 }
270 
271 static int clk_scu_atf_set_cpu_rate(struct clk_hw *hw, unsigned long rate,
272 				    unsigned long parent_rate)
273 {
274 	struct clk_scu *clk = to_clk_scu(hw);
275 	struct arm_smccc_res res;
276 	unsigned long cluster_id;
277 
278 	if (clk->rsrc_id == IMX_SC_R_A35 || clk->rsrc_id == IMX_SC_R_A53)
279 		cluster_id = 0;
280 	else if (clk->rsrc_id == IMX_SC_R_A72)
281 		cluster_id = 1;
282 	else
283 		return -EINVAL;
284 
285 	/* CPU frequency scaling can ONLY be done by ARM-Trusted-Firmware */
286 	arm_smccc_smc(IMX_SIP_CPUFREQ, IMX_SIP_SET_CPUFREQ,
287 		      cluster_id, rate, 0, 0, 0, 0, &res);
288 
289 	return 0;
290 }
291 
292 /*
293  * clk_scu_set_rate - Set rate for a SCU clock
294  * @hw: clock to change rate for
295  * @rate: target rate for the clock
296  * @parent_rate: rate of the clock parent, not used for SCU clocks
297  *
298  * Sets a clock frequency for a SCU clock. Returns the SCU
299  * protocol status.
300  */
301 static int clk_scu_set_rate(struct clk_hw *hw, unsigned long rate,
302 			    unsigned long parent_rate)
303 {
304 	struct clk_scu *clk = to_clk_scu(hw);
305 	struct imx_sc_msg_req_set_clock_rate msg;
306 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
307 
308 	hdr->ver = IMX_SC_RPC_VERSION;
309 	hdr->svc = IMX_SC_RPC_SVC_PM;
310 	hdr->func = IMX_SC_PM_FUNC_SET_CLOCK_RATE;
311 	hdr->size = 3;
312 
313 	msg.rate = cpu_to_le32(rate);
314 	msg.resource = cpu_to_le16(clk->rsrc_id);
315 	msg.clk = clk->clk_type;
316 
317 	return imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
318 }
319 
320 static u8 clk_scu_get_parent(struct clk_hw *hw)
321 {
322 	struct clk_scu *clk = to_clk_scu(hw);
323 	struct imx_sc_msg_get_clock_parent msg;
324 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
325 	int ret;
326 
327 	hdr->ver = IMX_SC_RPC_VERSION;
328 	hdr->svc = IMX_SC_RPC_SVC_PM;
329 	hdr->func = IMX_SC_PM_FUNC_GET_CLOCK_PARENT;
330 	hdr->size = 2;
331 
332 	msg.data.req.resource = cpu_to_le16(clk->rsrc_id);
333 	msg.data.req.clk = clk->clk_type;
334 
335 	ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
336 	if (ret) {
337 		pr_err("%s: failed to get clock parent %d\n",
338 		       clk_hw_get_name(hw), ret);
339 		return 0;
340 	}
341 
342 	clk->parent_index = msg.data.resp.parent;
343 
344 	return msg.data.resp.parent;
345 }
346 
347 static int clk_scu_set_parent(struct clk_hw *hw, u8 index)
348 {
349 	struct clk_scu *clk = to_clk_scu(hw);
350 	struct imx_sc_msg_set_clock_parent msg;
351 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
352 	int ret;
353 
354 	hdr->ver = IMX_SC_RPC_VERSION;
355 	hdr->svc = IMX_SC_RPC_SVC_PM;
356 	hdr->func = IMX_SC_PM_FUNC_SET_CLOCK_PARENT;
357 	hdr->size = 2;
358 
359 	msg.resource = cpu_to_le16(clk->rsrc_id);
360 	msg.clk = clk->clk_type;
361 	msg.parent = index;
362 
363 	ret = imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
364 	if (ret) {
365 		pr_err("%s: failed to set clock parent %d\n",
366 		       clk_hw_get_name(hw), ret);
367 		return ret;
368 	}
369 
370 	clk->parent_index = index;
371 
372 	return 0;
373 }
374 
375 static int sc_pm_clock_enable(struct imx_sc_ipc *ipc, u16 resource,
376 			      u8 clk, bool enable, bool autog)
377 {
378 	struct imx_sc_msg_req_clock_enable msg;
379 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
380 
381 	hdr->ver = IMX_SC_RPC_VERSION;
382 	hdr->svc = IMX_SC_RPC_SVC_PM;
383 	hdr->func = IMX_SC_PM_FUNC_CLOCK_ENABLE;
384 	hdr->size = 3;
385 
386 	msg.resource = cpu_to_le16(resource);
387 	msg.clk = clk;
388 	msg.enable = enable;
389 	msg.autog = autog;
390 
391 	return imx_scu_call_rpc(ccm_ipc_handle, &msg, true);
392 }
393 
394 /*
395  * clk_scu_prepare - Enable a SCU clock
396  * @hw: clock to enable
397  *
398  * Enable the clock at the DSC slice level
399  */
400 static int clk_scu_prepare(struct clk_hw *hw)
401 {
402 	struct clk_scu *clk = to_clk_scu(hw);
403 
404 	return sc_pm_clock_enable(ccm_ipc_handle, clk->rsrc_id,
405 				  clk->clk_type, true, false);
406 }
407 
408 /*
409  * clk_scu_unprepare - Disable a SCU clock
410  * @hw: clock to enable
411  *
412  * Disable the clock at the DSC slice level
413  */
414 static void clk_scu_unprepare(struct clk_hw *hw)
415 {
416 	struct clk_scu *clk = to_clk_scu(hw);
417 	int ret;
418 
419 	ret = sc_pm_clock_enable(ccm_ipc_handle, clk->rsrc_id,
420 				 clk->clk_type, false, false);
421 	if (ret)
422 		pr_warn("%s: clk unprepare failed %d\n", clk_hw_get_name(hw),
423 			ret);
424 }
425 
426 static const struct clk_ops clk_scu_ops = {
427 	.recalc_rate = clk_scu_recalc_rate,
428 	.round_rate = clk_scu_round_rate,
429 	.set_rate = clk_scu_set_rate,
430 	.get_parent = clk_scu_get_parent,
431 	.set_parent = clk_scu_set_parent,
432 	.prepare = clk_scu_prepare,
433 	.unprepare = clk_scu_unprepare,
434 };
435 
436 static const struct clk_ops clk_scu_cpu_ops = {
437 	.recalc_rate = clk_scu_recalc_rate,
438 	.round_rate = clk_scu_round_rate,
439 	.set_rate = clk_scu_atf_set_cpu_rate,
440 	.prepare = clk_scu_prepare,
441 	.unprepare = clk_scu_unprepare,
442 };
443 
444 static const struct clk_ops clk_scu_pi_ops = {
445 	.recalc_rate = clk_scu_recalc_rate,
446 	.round_rate  = clk_scu_round_rate,
447 	.set_rate    = clk_scu_set_rate,
448 };
449 
450 struct clk_hw *__imx_clk_scu(struct device *dev, const char *name,
451 			     const char * const *parents, int num_parents,
452 			     u32 rsrc_id, u8 clk_type)
453 {
454 	struct clk_init_data init;
455 	struct clk_scu *clk;
456 	struct clk_hw *hw;
457 	int ret;
458 
459 	clk = kzalloc(sizeof(*clk), GFP_KERNEL);
460 	if (!clk)
461 		return ERR_PTR(-ENOMEM);
462 
463 	clk->rsrc_id = rsrc_id;
464 	clk->clk_type = clk_type;
465 
466 	init.name = name;
467 	init.ops = &clk_scu_ops;
468 	if (rsrc_id == IMX_SC_R_A35 || rsrc_id == IMX_SC_R_A53 || rsrc_id == IMX_SC_R_A72)
469 		init.ops = &clk_scu_cpu_ops;
470 	else if (rsrc_id == IMX_SC_R_PI_0_PLL)
471 		init.ops = &clk_scu_pi_ops;
472 	else
473 		init.ops = &clk_scu_ops;
474 	init.parent_names = parents;
475 	init.num_parents = num_parents;
476 
477 	/*
478 	 * Note on MX8, the clocks are tightly coupled with power domain
479 	 * that once the power domain is off, the clock status may be
480 	 * lost. So we make it NOCACHE to let user to retrieve the real
481 	 * clock status from HW instead of using the possible invalid
482 	 * cached rate.
483 	 */
484 	init.flags = CLK_GET_RATE_NOCACHE;
485 	clk->hw.init = &init;
486 
487 	hw = &clk->hw;
488 	ret = clk_hw_register(dev, hw);
489 	if (ret) {
490 		kfree(clk);
491 		hw = ERR_PTR(ret);
492 		return hw;
493 	}
494 
495 	if (dev)
496 		dev_set_drvdata(dev, clk);
497 
498 	return hw;
499 }
500 
501 struct clk_hw *imx_scu_of_clk_src_get(struct of_phandle_args *clkspec,
502 				      void *data)
503 {
504 	unsigned int rsrc = clkspec->args[0];
505 	unsigned int idx = clkspec->args[1];
506 	struct list_head *scu_clks = data;
507 	struct imx_scu_clk_node *clk;
508 
509 	list_for_each_entry(clk, &scu_clks[rsrc], node) {
510 		if (clk->clk_type == idx)
511 			return clk->hw;
512 	}
513 
514 	return ERR_PTR(-ENODEV);
515 }
516 
517 static int imx_clk_scu_probe(struct platform_device *pdev)
518 {
519 	struct device *dev = &pdev->dev;
520 	struct imx_scu_clk_node *clk = dev_get_platdata(dev);
521 	struct clk_hw *hw;
522 	int ret;
523 
524 	if (!((clk->rsrc == IMX_SC_R_A35) || (clk->rsrc == IMX_SC_R_A53) ||
525 	    (clk->rsrc == IMX_SC_R_A72))) {
526 		pm_runtime_set_suspended(dev);
527 		pm_runtime_set_autosuspend_delay(dev, 50);
528 		pm_runtime_use_autosuspend(&pdev->dev);
529 		pm_runtime_enable(dev);
530 
531 		ret = pm_runtime_resume_and_get(dev);
532 		if (ret) {
533 			pm_genpd_remove_device(dev);
534 			pm_runtime_disable(dev);
535 			return ret;
536 		}
537 	}
538 
539 	hw = __imx_clk_scu(dev, clk->name, clk->parents, clk->num_parents,
540 			   clk->rsrc, clk->clk_type);
541 	if (IS_ERR(hw)) {
542 		pm_runtime_disable(dev);
543 		return PTR_ERR(hw);
544 	}
545 
546 	clk->hw = hw;
547 	list_add_tail(&clk->node, &imx_scu_clks[clk->rsrc]);
548 
549 	if (!((clk->rsrc == IMX_SC_R_A35) || (clk->rsrc == IMX_SC_R_A53) ||
550 	    (clk->rsrc == IMX_SC_R_A72))) {
551 		pm_runtime_mark_last_busy(&pdev->dev);
552 		pm_runtime_put_autosuspend(&pdev->dev);
553 	}
554 
555 	dev_dbg(dev, "register SCU clock rsrc:%d type:%d\n", clk->rsrc,
556 		clk->clk_type);
557 
558 	return 0;
559 }
560 
561 static int __maybe_unused imx_clk_scu_suspend(struct device *dev)
562 {
563 	struct clk_scu *clk = dev_get_drvdata(dev);
564 	u32 rsrc_id = clk->rsrc_id;
565 
566 	if ((rsrc_id == IMX_SC_R_A35) || (rsrc_id == IMX_SC_R_A53) ||
567 	    (rsrc_id == IMX_SC_R_A72))
568 		return 0;
569 
570 	clk->parent = clk_hw_get_parent(&clk->hw);
571 
572 	/* DC SS needs to handle bypass clock using non-cached clock rate */
573 	if (clk->rsrc_id == IMX_SC_R_DC_0_VIDEO0 ||
574 		clk->rsrc_id == IMX_SC_R_DC_0_VIDEO1 ||
575 		clk->rsrc_id == IMX_SC_R_DC_1_VIDEO0 ||
576 		clk->rsrc_id == IMX_SC_R_DC_1_VIDEO1)
577 		clk->rate = clk_scu_recalc_rate(&clk->hw, 0);
578 	else
579 		clk->rate = clk_hw_get_rate(&clk->hw);
580 	clk->is_enabled = clk_hw_is_enabled(&clk->hw);
581 
582 	if (clk->parent)
583 		dev_dbg(dev, "save parent %s idx %u\n", clk_hw_get_name(clk->parent),
584 			clk->parent_index);
585 
586 	if (clk->rate)
587 		dev_dbg(dev, "save rate %d\n", clk->rate);
588 
589 	if (clk->is_enabled)
590 		dev_dbg(dev, "save enabled state\n");
591 
592 	return 0;
593 }
594 
595 static int __maybe_unused imx_clk_scu_resume(struct device *dev)
596 {
597 	struct clk_scu *clk = dev_get_drvdata(dev);
598 	u32 rsrc_id = clk->rsrc_id;
599 	int ret = 0;
600 
601 	if ((rsrc_id == IMX_SC_R_A35) || (rsrc_id == IMX_SC_R_A53) ||
602 	    (rsrc_id == IMX_SC_R_A72))
603 		return 0;
604 
605 	if (clk->parent) {
606 		ret = clk_scu_set_parent(&clk->hw, clk->parent_index);
607 		dev_dbg(dev, "restore parent %s idx %u %s\n",
608 			clk_hw_get_name(clk->parent),
609 			clk->parent_index, !ret ? "success" : "failed");
610 	}
611 
612 	if (clk->rate) {
613 		ret = clk_scu_set_rate(&clk->hw, clk->rate, 0);
614 		dev_dbg(dev, "restore rate %d %s\n", clk->rate,
615 			!ret ? "success" : "failed");
616 	}
617 
618 	if (clk->is_enabled && rsrc_id != IMX_SC_R_PI_0_PLL) {
619 		ret = clk_scu_prepare(&clk->hw);
620 		dev_dbg(dev, "restore enabled state %s\n",
621 			!ret ? "success" : "failed");
622 	}
623 
624 	return ret;
625 }
626 
627 static const struct dev_pm_ops imx_clk_scu_pm_ops = {
628 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_clk_scu_suspend,
629 				      imx_clk_scu_resume)
630 };
631 
632 static struct platform_driver imx_clk_scu_driver = {
633 	.driver = {
634 		.name = "imx-scu-clk",
635 		.suppress_bind_attrs = true,
636 		.pm = &imx_clk_scu_pm_ops,
637 	},
638 	.probe = imx_clk_scu_probe,
639 };
640 
641 static int imx_clk_scu_attach_pd(struct device *dev, u32 rsrc_id)
642 {
643 	struct of_phandle_args genpdspec = {
644 		.np = pd_np,
645 		.args_count = 1,
646 		.args[0] = rsrc_id,
647 	};
648 
649 	if (rsrc_id == IMX_SC_R_A35 || rsrc_id == IMX_SC_R_A53 ||
650 	    rsrc_id == IMX_SC_R_A72)
651 		return 0;
652 
653 	return of_genpd_add_device(&genpdspec, dev);
654 }
655 
656 struct clk_hw *imx_clk_scu_alloc_dev(const char *name,
657 				     const char * const *parents,
658 				     int num_parents, u32 rsrc_id, u8 clk_type)
659 {
660 	struct imx_scu_clk_node clk = {
661 		.name = name,
662 		.rsrc = rsrc_id,
663 		.clk_type = clk_type,
664 		.parents = parents,
665 		.num_parents = num_parents,
666 	};
667 	struct platform_device *pdev;
668 	int ret;
669 
670 	if (!imx_scu_clk_is_valid(rsrc_id))
671 		return ERR_PTR(-EINVAL);
672 
673 	pdev = platform_device_alloc(name, PLATFORM_DEVID_NONE);
674 	if (!pdev) {
675 		pr_err("%s: failed to allocate scu clk dev rsrc %d type %d\n",
676 		       name, rsrc_id, clk_type);
677 		return ERR_PTR(-ENOMEM);
678 	}
679 
680 	ret = platform_device_add_data(pdev, &clk, sizeof(clk));
681 	if (ret) {
682 		platform_device_put(pdev);
683 		return ERR_PTR(ret);
684 	}
685 
686 	ret = driver_set_override(&pdev->dev, &pdev->driver_override,
687 				  "imx-scu-clk", strlen("imx-scu-clk"));
688 	if (ret) {
689 		platform_device_put(pdev);
690 		return ERR_PTR(ret);
691 	}
692 
693 	ret = imx_clk_scu_attach_pd(&pdev->dev, rsrc_id);
694 	if (ret)
695 		pr_warn("%s: failed to attached the power domain %d\n",
696 			name, ret);
697 
698 	ret = platform_device_add(pdev);
699 	if (ret) {
700 		platform_device_put(pdev);
701 		return ERR_PTR(ret);
702 	}
703 
704 	/* For API backwards compatiblilty, simply return NULL for success */
705 	return NULL;
706 }
707 
708 void imx_clk_scu_unregister(void)
709 {
710 	struct imx_scu_clk_node *clk;
711 	int i;
712 
713 	for (i = 0; i < IMX_SC_R_LAST; i++) {
714 		list_for_each_entry(clk, &imx_scu_clks[i], node) {
715 			clk_hw_unregister(clk->hw);
716 			kfree(clk);
717 		}
718 	}
719 }
720 
721 static unsigned long clk_gpr_div_scu_recalc_rate(struct clk_hw *hw,
722 						 unsigned long parent_rate)
723 {
724 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
725 	unsigned long rate = 0;
726 	u32 val;
727 	int err;
728 
729 	err = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
730 				      clk->gpr_id, &val);
731 
732 	rate  = val ? parent_rate / 2 : parent_rate;
733 
734 	return err ? 0 : rate;
735 }
736 
737 static long clk_gpr_div_scu_round_rate(struct clk_hw *hw, unsigned long rate,
738 				   unsigned long *prate)
739 {
740 	if (rate < *prate)
741 		rate = *prate / 2;
742 	else
743 		rate = *prate;
744 
745 	return rate;
746 }
747 
748 static int clk_gpr_div_scu_set_rate(struct clk_hw *hw, unsigned long rate,
749 				    unsigned long parent_rate)
750 {
751 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
752 	uint32_t val;
753 	int err;
754 
755 	val = (rate < parent_rate) ? 1 : 0;
756 	err = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
757 				      clk->gpr_id, val);
758 
759 	return err ? -EINVAL : 0;
760 }
761 
762 static const struct clk_ops clk_gpr_div_scu_ops = {
763 	.recalc_rate = clk_gpr_div_scu_recalc_rate,
764 	.round_rate = clk_gpr_div_scu_round_rate,
765 	.set_rate = clk_gpr_div_scu_set_rate,
766 };
767 
768 static u8 clk_gpr_mux_scu_get_parent(struct clk_hw *hw)
769 {
770 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
771 	u32 val = 0;
772 
773 	imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
774 				clk->gpr_id, &val);
775 
776 	return (u8)val;
777 }
778 
779 static int clk_gpr_mux_scu_set_parent(struct clk_hw *hw, u8 index)
780 {
781 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
782 
783 	return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
784 				       clk->gpr_id, index);
785 }
786 
787 static const struct clk_ops clk_gpr_mux_scu_ops = {
788 	.get_parent = clk_gpr_mux_scu_get_parent,
789 	.set_parent = clk_gpr_mux_scu_set_parent,
790 };
791 
792 static int clk_gpr_gate_scu_prepare(struct clk_hw *hw)
793 {
794 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
795 
796 	return imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
797 				       clk->gpr_id, !clk->gate_invert);
798 }
799 
800 static void clk_gpr_gate_scu_unprepare(struct clk_hw *hw)
801 {
802 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
803 	int ret;
804 
805 	ret = imx_sc_misc_set_control(ccm_ipc_handle, clk->rsrc_id,
806 				      clk->gpr_id, clk->gate_invert);
807 	if (ret)
808 		pr_err("%s: clk unprepare failed %d\n", clk_hw_get_name(hw),
809 		       ret);
810 }
811 
812 static int clk_gpr_gate_scu_is_prepared(struct clk_hw *hw)
813 {
814 	struct clk_gpr_scu *clk = to_clk_gpr_scu(hw);
815 	int ret;
816 	u32 val;
817 
818 	ret = imx_sc_misc_get_control(ccm_ipc_handle, clk->rsrc_id,
819 				      clk->gpr_id, &val);
820 	if (ret)
821 		return ret;
822 
823 	return clk->gate_invert ? !val : val;
824 }
825 
826 static const struct clk_ops clk_gpr_gate_scu_ops = {
827 	.prepare = clk_gpr_gate_scu_prepare,
828 	.unprepare = clk_gpr_gate_scu_unprepare,
829 	.is_prepared = clk_gpr_gate_scu_is_prepared,
830 };
831 
832 struct clk_hw *__imx_clk_gpr_scu(const char *name, const char * const *parent_name,
833 				 int num_parents, u32 rsrc_id, u8 gpr_id, u8 flags,
834 				 bool invert)
835 {
836 	struct imx_scu_clk_node *clk_node;
837 	struct clk_gpr_scu *clk;
838 	struct clk_hw *hw;
839 	struct clk_init_data init;
840 	int ret;
841 
842 	if (rsrc_id >= IMX_SC_R_LAST || gpr_id >= IMX_SC_C_LAST)
843 		return ERR_PTR(-EINVAL);
844 
845 	clk_node = kzalloc(sizeof(*clk_node), GFP_KERNEL);
846 	if (!clk_node)
847 		return ERR_PTR(-ENOMEM);
848 
849 	if (!imx_scu_clk_is_valid(rsrc_id)) {
850 		kfree(clk_node);
851 		return ERR_PTR(-EINVAL);
852 	}
853 
854 	clk = kzalloc(sizeof(*clk), GFP_KERNEL);
855 	if (!clk) {
856 		kfree(clk_node);
857 		return ERR_PTR(-ENOMEM);
858 	}
859 
860 	clk->rsrc_id = rsrc_id;
861 	clk->gpr_id = gpr_id;
862 	clk->flags = flags;
863 	clk->gate_invert = invert;
864 
865 	if (flags & IMX_SCU_GPR_CLK_GATE)
866 		init.ops = &clk_gpr_gate_scu_ops;
867 
868 	if (flags & IMX_SCU_GPR_CLK_DIV)
869 		init.ops = &clk_gpr_div_scu_ops;
870 
871 	if (flags & IMX_SCU_GPR_CLK_MUX)
872 		init.ops = &clk_gpr_mux_scu_ops;
873 
874 	init.flags = 0;
875 	init.name = name;
876 	init.parent_names = parent_name;
877 	init.num_parents = num_parents;
878 
879 	clk->hw.init = &init;
880 
881 	hw = &clk->hw;
882 	ret = clk_hw_register(NULL, hw);
883 	if (ret) {
884 		kfree(clk);
885 		kfree(clk_node);
886 		hw = ERR_PTR(ret);
887 	} else {
888 		clk_node->hw = hw;
889 		clk_node->clk_type = gpr_id;
890 		list_add_tail(&clk_node->node, &imx_scu_clks[rsrc_id]);
891 	}
892 
893 	return hw;
894 }
895