xref: /linux/drivers/devfreq/rk3399_dmc.c (revision 447e140e66fd226350b3ce86cffc965eaae4c856)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd.
4  * Author: Lin Huang <hl@rock-chips.com>
5  */
6 
7 #include <linux/arm-smccc.h>
8 #include <linux/bitfield.h>
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/devfreq.h>
12 #include <linux/devfreq-event.h>
13 #include <linux/interrupt.h>
14 #include <linux/mfd/syscon.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_opp.h>
19 #include <linux/regmap.h>
20 #include <linux/regulator/consumer.h>
21 #include <linux/rwsem.h>
22 #include <linux/suspend.h>
23 
24 #include <soc/rockchip/pm_domains.h>
25 #include <soc/rockchip/rockchip_grf.h>
26 #include <soc/rockchip/rk3399_grf.h>
27 #include <soc/rockchip/rockchip_sip.h>
28 
29 #define NS_TO_CYCLE(NS, MHz)				(((NS) * (MHz)) / NSEC_PER_USEC)
30 
31 #define RK3399_SET_ODT_PD_0_SR_IDLE			GENMASK(7, 0)
32 #define RK3399_SET_ODT_PD_0_SR_MC_GATE_IDLE		GENMASK(15, 8)
33 #define RK3399_SET_ODT_PD_0_STANDBY_IDLE		GENMASK(31, 16)
34 
35 #define RK3399_SET_ODT_PD_1_PD_IDLE			GENMASK(11, 0)
36 #define RK3399_SET_ODT_PD_1_SRPD_LITE_IDLE		GENMASK(27, 16)
37 
38 #define RK3399_SET_ODT_PD_2_ODT_ENABLE			BIT(0)
39 
40 struct rk3399_dmcfreq {
41 	struct device *dev;
42 	struct devfreq *devfreq;
43 	struct devfreq_dev_profile profile;
44 	struct devfreq_simple_ondemand_data ondemand_data;
45 	struct clk *dmc_clk;
46 	struct devfreq_event_dev *edev;
47 	struct mutex lock;
48 	struct regulator *vdd_center;
49 	struct regmap *regmap_pmu;
50 	unsigned long rate, target_rate;
51 	unsigned long volt, target_volt;
52 	unsigned int odt_dis_freq;
53 
54 	unsigned int pd_idle_ns;
55 	unsigned int sr_idle_ns;
56 	unsigned int sr_mc_gate_idle_ns;
57 	unsigned int srpd_lite_idle_ns;
58 	unsigned int standby_idle_ns;
59 	unsigned int ddr3_odt_dis_freq;
60 	unsigned int lpddr3_odt_dis_freq;
61 	unsigned int lpddr4_odt_dis_freq;
62 
63 	unsigned int pd_idle_dis_freq;
64 	unsigned int sr_idle_dis_freq;
65 	unsigned int sr_mc_gate_idle_dis_freq;
66 	unsigned int srpd_lite_idle_dis_freq;
67 	unsigned int standby_idle_dis_freq;
68 };
69 
70 static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
71 				 u32 flags)
72 {
73 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
74 	struct dev_pm_opp *opp;
75 	unsigned long old_clk_rate = dmcfreq->rate;
76 	unsigned long target_volt, target_rate;
77 	unsigned int ddrcon_mhz;
78 	struct arm_smccc_res res;
79 	int err;
80 
81 	u32 odt_pd_arg0 = 0;
82 	u32 odt_pd_arg1 = 0;
83 	u32 odt_pd_arg2 = 0;
84 
85 	opp = devfreq_recommended_opp(dev, freq, flags);
86 	if (IS_ERR(opp))
87 		return PTR_ERR(opp);
88 
89 	target_rate = dev_pm_opp_get_freq(opp);
90 	target_volt = dev_pm_opp_get_voltage(opp);
91 	dev_pm_opp_put(opp);
92 
93 	if (dmcfreq->rate == target_rate)
94 		return 0;
95 
96 	mutex_lock(&dmcfreq->lock);
97 
98 	/*
99 	 * Ensure power-domain transitions don't interfere with ARM Trusted
100 	 * Firmware power-domain idling.
101 	 */
102 	err = rockchip_pmu_block();
103 	if (err) {
104 		dev_err(dev, "Failed to block PMU: %d\n", err);
105 		goto out_unlock;
106 	}
107 
108 	/*
109 	 * Some idle parameters may be based on the DDR controller clock, which
110 	 * is half of the DDR frequency.
111 	 * pd_idle and standby_idle are based on the controller clock cycle.
112 	 * sr_idle_cycle, sr_mc_gate_idle_cycle, and srpd_lite_idle_cycle
113 	 * are based on the 1024 controller clock cycle
114 	 */
115 	ddrcon_mhz = target_rate / USEC_PER_SEC / 2;
116 
117 	u32p_replace_bits(&odt_pd_arg1,
118 			  NS_TO_CYCLE(dmcfreq->pd_idle_ns, ddrcon_mhz),
119 			  RK3399_SET_ODT_PD_1_PD_IDLE);
120 	u32p_replace_bits(&odt_pd_arg0,
121 			  NS_TO_CYCLE(dmcfreq->standby_idle_ns, ddrcon_mhz),
122 			  RK3399_SET_ODT_PD_0_STANDBY_IDLE);
123 	u32p_replace_bits(&odt_pd_arg0,
124 			  DIV_ROUND_UP(NS_TO_CYCLE(dmcfreq->sr_idle_ns,
125 						   ddrcon_mhz), 1024),
126 			  RK3399_SET_ODT_PD_0_SR_IDLE);
127 	u32p_replace_bits(&odt_pd_arg0,
128 			  DIV_ROUND_UP(NS_TO_CYCLE(dmcfreq->sr_mc_gate_idle_ns,
129 						   ddrcon_mhz), 1024),
130 			  RK3399_SET_ODT_PD_0_SR_MC_GATE_IDLE);
131 	u32p_replace_bits(&odt_pd_arg1,
132 			  DIV_ROUND_UP(NS_TO_CYCLE(dmcfreq->srpd_lite_idle_ns,
133 						   ddrcon_mhz), 1024),
134 			  RK3399_SET_ODT_PD_1_SRPD_LITE_IDLE);
135 
136 	if (dmcfreq->regmap_pmu) {
137 		if (target_rate >= dmcfreq->sr_idle_dis_freq)
138 			odt_pd_arg0 &= ~RK3399_SET_ODT_PD_0_SR_IDLE;
139 
140 		if (target_rate >= dmcfreq->sr_mc_gate_idle_dis_freq)
141 			odt_pd_arg0 &= ~RK3399_SET_ODT_PD_0_SR_MC_GATE_IDLE;
142 
143 		if (target_rate >= dmcfreq->standby_idle_dis_freq)
144 			odt_pd_arg0 &= ~RK3399_SET_ODT_PD_0_STANDBY_IDLE;
145 
146 		if (target_rate >= dmcfreq->pd_idle_dis_freq)
147 			odt_pd_arg1 &= ~RK3399_SET_ODT_PD_1_PD_IDLE;
148 
149 		if (target_rate >= dmcfreq->srpd_lite_idle_dis_freq)
150 			odt_pd_arg1 &= ~RK3399_SET_ODT_PD_1_SRPD_LITE_IDLE;
151 
152 		if (target_rate >= dmcfreq->odt_dis_freq)
153 			odt_pd_arg2 |= RK3399_SET_ODT_PD_2_ODT_ENABLE;
154 
155 		/*
156 		 * This makes a SMC call to the TF-A to set the DDR PD
157 		 * (power-down) timings and to enable or disable the
158 		 * ODT (on-die termination) resistors.
159 		 */
160 		arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, odt_pd_arg0, odt_pd_arg1,
161 			      ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD, odt_pd_arg2,
162 			      0, 0, 0, &res);
163 	}
164 
165 	/*
166 	 * If frequency scaling from low to high, adjust voltage first.
167 	 * If frequency scaling from high to low, adjust frequency first.
168 	 */
169 	if (old_clk_rate < target_rate) {
170 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
171 					    target_volt);
172 		if (err) {
173 			dev_err(dev, "Cannot set voltage %lu uV\n",
174 				target_volt);
175 			goto out;
176 		}
177 	}
178 
179 	err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
180 	if (err) {
181 		dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
182 			err);
183 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
184 				      dmcfreq->volt);
185 		goto out;
186 	}
187 
188 	/*
189 	 * Check the dpll rate,
190 	 * There only two result we will get,
191 	 * 1. Ddr frequency scaling fail, we still get the old rate.
192 	 * 2. Ddr frequency scaling sucessful, we get the rate we set.
193 	 */
194 	dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
195 
196 	/* If get the incorrect rate, set voltage to old value. */
197 	if (dmcfreq->rate != target_rate) {
198 		dev_err(dev, "Got wrong frequency, Request %lu, Current %lu\n",
199 			target_rate, dmcfreq->rate);
200 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
201 				      dmcfreq->volt);
202 		goto out;
203 	} else if (old_clk_rate > target_rate)
204 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
205 					    target_volt);
206 	if (err)
207 		dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
208 
209 	dmcfreq->rate = target_rate;
210 	dmcfreq->volt = target_volt;
211 
212 out:
213 	rockchip_pmu_unblock();
214 out_unlock:
215 	mutex_unlock(&dmcfreq->lock);
216 	return err;
217 }
218 
219 static int rk3399_dmcfreq_get_dev_status(struct device *dev,
220 					 struct devfreq_dev_status *stat)
221 {
222 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
223 	struct devfreq_event_data edata;
224 	int ret = 0;
225 
226 	ret = devfreq_event_get_event(dmcfreq->edev, &edata);
227 	if (ret < 0)
228 		return ret;
229 
230 	stat->current_frequency = dmcfreq->rate;
231 	stat->busy_time = edata.load_count;
232 	stat->total_time = edata.total_count;
233 
234 	return ret;
235 }
236 
237 static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
238 {
239 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
240 
241 	*freq = dmcfreq->rate;
242 
243 	return 0;
244 }
245 
246 static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
247 {
248 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
249 	int ret = 0;
250 
251 	ret = devfreq_event_disable_edev(dmcfreq->edev);
252 	if (ret < 0) {
253 		dev_err(dev, "failed to disable the devfreq-event devices\n");
254 		return ret;
255 	}
256 
257 	ret = devfreq_suspend_device(dmcfreq->devfreq);
258 	if (ret < 0) {
259 		dev_err(dev, "failed to suspend the devfreq devices\n");
260 		return ret;
261 	}
262 
263 	return 0;
264 }
265 
266 static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
267 {
268 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
269 	int ret = 0;
270 
271 	ret = devfreq_event_enable_edev(dmcfreq->edev);
272 	if (ret < 0) {
273 		dev_err(dev, "failed to enable the devfreq-event devices\n");
274 		return ret;
275 	}
276 
277 	ret = devfreq_resume_device(dmcfreq->devfreq);
278 	if (ret < 0) {
279 		dev_err(dev, "failed to resume the devfreq devices\n");
280 		return ret;
281 	}
282 	return ret;
283 }
284 
285 static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
286 			 rk3399_dmcfreq_resume);
287 
288 static int rk3399_dmcfreq_of_props(struct rk3399_dmcfreq *data,
289 				   struct device_node *np)
290 {
291 	int ret = 0;
292 
293 	/*
294 	 * These are all optional, and serve as minimum bounds. Give them large
295 	 * (i.e., never "disabled") values if the DT doesn't specify one.
296 	 */
297 	data->pd_idle_dis_freq =
298 		data->sr_idle_dis_freq =
299 		data->sr_mc_gate_idle_dis_freq =
300 		data->srpd_lite_idle_dis_freq =
301 		data->standby_idle_dis_freq = UINT_MAX;
302 
303 	ret |= of_property_read_u32(np, "rockchip,pd-idle-ns",
304 				    &data->pd_idle_ns);
305 	ret |= of_property_read_u32(np, "rockchip,sr-idle-ns",
306 				    &data->sr_idle_ns);
307 	ret |= of_property_read_u32(np, "rockchip,sr-mc-gate-idle-ns",
308 				    &data->sr_mc_gate_idle_ns);
309 	ret |= of_property_read_u32(np, "rockchip,srpd-lite-idle-ns",
310 				    &data->srpd_lite_idle_ns);
311 	ret |= of_property_read_u32(np, "rockchip,standby-idle-ns",
312 				    &data->standby_idle_ns);
313 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt_dis_freq",
314 				    &data->ddr3_odt_dis_freq);
315 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt_dis_freq",
316 				    &data->lpddr3_odt_dis_freq);
317 	ret |= of_property_read_u32(np, "rockchip,lpddr4_odt_dis_freq",
318 				    &data->lpddr4_odt_dis_freq);
319 
320 	ret |= of_property_read_u32(np, "rockchip,pd-idle-dis-freq-hz",
321 				    &data->pd_idle_dis_freq);
322 	ret |= of_property_read_u32(np, "rockchip,sr-idle-dis-freq-hz",
323 				    &data->sr_idle_dis_freq);
324 	ret |= of_property_read_u32(np, "rockchip,sr-mc-gate-idle-dis-freq-hz",
325 				    &data->sr_mc_gate_idle_dis_freq);
326 	ret |= of_property_read_u32(np, "rockchip,srpd-lite-idle-dis-freq-hz",
327 				    &data->srpd_lite_idle_dis_freq);
328 	ret |= of_property_read_u32(np, "rockchip,standby-idle-dis-freq-hz",
329 				    &data->standby_idle_dis_freq);
330 
331 	return ret;
332 }
333 
334 static int rk3399_dmcfreq_probe(struct platform_device *pdev)
335 {
336 	struct arm_smccc_res res;
337 	struct device *dev = &pdev->dev;
338 	struct device_node *np = pdev->dev.of_node, *node;
339 	struct rk3399_dmcfreq *data;
340 	int ret;
341 	struct dev_pm_opp *opp;
342 	u32 ddr_type;
343 	u32 val;
344 
345 	data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
346 	if (!data)
347 		return -ENOMEM;
348 
349 	mutex_init(&data->lock);
350 
351 	data->vdd_center = devm_regulator_get(dev, "center");
352 	if (IS_ERR(data->vdd_center))
353 		return dev_err_probe(dev, PTR_ERR(data->vdd_center),
354 				     "Cannot get the regulator \"center\"\n");
355 
356 	data->dmc_clk = devm_clk_get(dev, "dmc_clk");
357 	if (IS_ERR(data->dmc_clk))
358 		return dev_err_probe(dev, PTR_ERR(data->dmc_clk),
359 				     "Cannot get the clk dmc_clk\n");
360 
361 	data->edev = devfreq_event_get_edev_by_phandle(dev, "devfreq-events", 0);
362 	if (IS_ERR(data->edev))
363 		return -EPROBE_DEFER;
364 
365 	ret = devfreq_event_enable_edev(data->edev);
366 	if (ret < 0) {
367 		dev_err(dev, "failed to enable devfreq-event devices\n");
368 		return ret;
369 	}
370 
371 	rk3399_dmcfreq_of_props(data, np);
372 
373 	node = of_parse_phandle(np, "rockchip,pmu", 0);
374 	if (!node)
375 		goto no_pmu;
376 
377 	data->regmap_pmu = syscon_node_to_regmap(node);
378 	of_node_put(node);
379 	if (IS_ERR(data->regmap_pmu)) {
380 		ret = PTR_ERR(data->regmap_pmu);
381 		goto err_edev;
382 	}
383 
384 	regmap_read(data->regmap_pmu, RK3399_PMUGRF_OS_REG2, &val);
385 	ddr_type = FIELD_GET(RK3399_PMUGRF_OS_REG2_DDRTYPE, val);
386 
387 	switch (ddr_type) {
388 	case ROCKCHIP_DDRTYPE_DDR3:
389 		data->odt_dis_freq = data->ddr3_odt_dis_freq;
390 		break;
391 	case ROCKCHIP_DDRTYPE_LPDDR3:
392 		data->odt_dis_freq = data->lpddr3_odt_dis_freq;
393 		break;
394 	case ROCKCHIP_DDRTYPE_LPDDR4:
395 		data->odt_dis_freq = data->lpddr4_odt_dis_freq;
396 		break;
397 	default:
398 		ret = -EINVAL;
399 		goto err_edev;
400 	}
401 
402 no_pmu:
403 	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
404 		      ROCKCHIP_SIP_CONFIG_DRAM_INIT,
405 		      0, 0, 0, 0, &res);
406 
407 	/*
408 	 * We add a devfreq driver to our parent since it has a device tree node
409 	 * with operating points.
410 	 */
411 	if (devm_pm_opp_of_add_table(dev)) {
412 		dev_err(dev, "Invalid operating-points in device tree.\n");
413 		ret = -EINVAL;
414 		goto err_edev;
415 	}
416 
417 	data->ondemand_data.upthreshold = 25;
418 	data->ondemand_data.downdifferential = 15;
419 
420 	data->rate = clk_get_rate(data->dmc_clk);
421 
422 	opp = devfreq_recommended_opp(dev, &data->rate, 0);
423 	if (IS_ERR(opp)) {
424 		ret = PTR_ERR(opp);
425 		goto err_edev;
426 	}
427 
428 	data->rate = dev_pm_opp_get_freq(opp);
429 	data->volt = dev_pm_opp_get_voltage(opp);
430 	dev_pm_opp_put(opp);
431 
432 	data->profile = (struct devfreq_dev_profile) {
433 		.polling_ms	= 200,
434 		.target		= rk3399_dmcfreq_target,
435 		.get_dev_status	= rk3399_dmcfreq_get_dev_status,
436 		.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
437 		.initial_freq	= data->rate,
438 	};
439 
440 	data->devfreq = devm_devfreq_add_device(dev,
441 					   &data->profile,
442 					   DEVFREQ_GOV_SIMPLE_ONDEMAND,
443 					   &data->ondemand_data);
444 	if (IS_ERR(data->devfreq)) {
445 		ret = PTR_ERR(data->devfreq);
446 		goto err_edev;
447 	}
448 
449 	devm_devfreq_register_opp_notifier(dev, data->devfreq);
450 
451 	data->dev = dev;
452 	platform_set_drvdata(pdev, data);
453 
454 	return 0;
455 
456 err_edev:
457 	devfreq_event_disable_edev(data->edev);
458 
459 	return ret;
460 }
461 
462 static void rk3399_dmcfreq_remove(struct platform_device *pdev)
463 {
464 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(&pdev->dev);
465 
466 	devfreq_event_disable_edev(dmcfreq->edev);
467 }
468 
469 static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
470 	{ .compatible = "rockchip,rk3399-dmc" },
471 	{ },
472 };
473 MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
474 
475 static struct platform_driver rk3399_dmcfreq_driver = {
476 	.probe	= rk3399_dmcfreq_probe,
477 	.remove_new = rk3399_dmcfreq_remove,
478 	.driver = {
479 		.name	= "rk3399-dmc-freq",
480 		.pm	= &rk3399_dmcfreq_pm,
481 		.of_match_table = rk3399dmc_devfreq_of_match,
482 	},
483 };
484 module_platform_driver(rk3399_dmcfreq_driver);
485 
486 MODULE_LICENSE("GPL v2");
487 MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
488 MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
489