xref: /linux/drivers/devfreq/rk3399_dmc.c (revision defec178df76e0caadd4e8ef68f3d655a2088198)
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/rk3399_grf.h>
25 #include <soc/rockchip/rockchip_sip.h>
26 
27 #define NS_TO_CYCLE(NS, MHz)				(((NS) * (MHz)) / NSEC_PER_USEC)
28 
29 #define RK3399_SET_ODT_PD_0_SR_IDLE			GENMASK(7, 0)
30 #define RK3399_SET_ODT_PD_0_SR_MC_GATE_IDLE		GENMASK(15, 8)
31 #define RK3399_SET_ODT_PD_0_STANDBY_IDLE		GENMASK(31, 16)
32 
33 #define RK3399_SET_ODT_PD_1_PD_IDLE			GENMASK(11, 0)
34 #define RK3399_SET_ODT_PD_1_SRPD_LITE_IDLE		GENMASK(27, 16)
35 
36 #define RK3399_SET_ODT_PD_2_ODT_ENABLE			BIT(0)
37 
38 struct rk3399_dmcfreq {
39 	struct device *dev;
40 	struct devfreq *devfreq;
41 	struct devfreq_dev_profile profile;
42 	struct devfreq_simple_ondemand_data ondemand_data;
43 	struct clk *dmc_clk;
44 	struct devfreq_event_dev *edev;
45 	struct mutex lock;
46 	struct regulator *vdd_center;
47 	struct regmap *regmap_pmu;
48 	unsigned long rate, target_rate;
49 	unsigned long volt, target_volt;
50 	unsigned int odt_dis_freq;
51 
52 	unsigned int pd_idle_ns;
53 	unsigned int sr_idle_ns;
54 	unsigned int sr_mc_gate_idle_ns;
55 	unsigned int srpd_lite_idle_ns;
56 	unsigned int standby_idle_ns;
57 	unsigned int ddr3_odt_dis_freq;
58 	unsigned int lpddr3_odt_dis_freq;
59 	unsigned int lpddr4_odt_dis_freq;
60 
61 	unsigned int pd_idle_dis_freq;
62 	unsigned int sr_idle_dis_freq;
63 	unsigned int sr_mc_gate_idle_dis_freq;
64 	unsigned int srpd_lite_idle_dis_freq;
65 	unsigned int standby_idle_dis_freq;
66 };
67 
68 static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
69 				 u32 flags)
70 {
71 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
72 	struct dev_pm_opp *opp;
73 	unsigned long old_clk_rate = dmcfreq->rate;
74 	unsigned long target_volt, target_rate;
75 	unsigned int ddrcon_mhz;
76 	struct arm_smccc_res res;
77 	int err;
78 
79 	u32 odt_pd_arg0 = 0;
80 	u32 odt_pd_arg1 = 0;
81 	u32 odt_pd_arg2 = 0;
82 
83 	opp = devfreq_recommended_opp(dev, freq, flags);
84 	if (IS_ERR(opp))
85 		return PTR_ERR(opp);
86 
87 	target_rate = dev_pm_opp_get_freq(opp);
88 	target_volt = dev_pm_opp_get_voltage(opp);
89 	dev_pm_opp_put(opp);
90 
91 	if (dmcfreq->rate == target_rate)
92 		return 0;
93 
94 	mutex_lock(&dmcfreq->lock);
95 
96 	/*
97 	 * Some idle parameters may be based on the DDR controller clock, which
98 	 * is half of the DDR frequency.
99 	 * pd_idle and standby_idle are based on the controller clock cycle.
100 	 * sr_idle_cycle, sr_mc_gate_idle_cycle, and srpd_lite_idle_cycle
101 	 * are based on the 1024 controller clock cycle
102 	 */
103 	ddrcon_mhz = target_rate / USEC_PER_SEC / 2;
104 
105 	u32p_replace_bits(&odt_pd_arg1,
106 			  NS_TO_CYCLE(dmcfreq->pd_idle_ns, ddrcon_mhz),
107 			  RK3399_SET_ODT_PD_1_PD_IDLE);
108 	u32p_replace_bits(&odt_pd_arg0,
109 			  NS_TO_CYCLE(dmcfreq->standby_idle_ns, ddrcon_mhz),
110 			  RK3399_SET_ODT_PD_0_STANDBY_IDLE);
111 	u32p_replace_bits(&odt_pd_arg0,
112 			  DIV_ROUND_UP(NS_TO_CYCLE(dmcfreq->sr_idle_ns,
113 						   ddrcon_mhz), 1024),
114 			  RK3399_SET_ODT_PD_0_SR_IDLE);
115 	u32p_replace_bits(&odt_pd_arg0,
116 			  DIV_ROUND_UP(NS_TO_CYCLE(dmcfreq->sr_mc_gate_idle_ns,
117 						   ddrcon_mhz), 1024),
118 			  RK3399_SET_ODT_PD_0_SR_MC_GATE_IDLE);
119 	u32p_replace_bits(&odt_pd_arg1,
120 			  DIV_ROUND_UP(NS_TO_CYCLE(dmcfreq->srpd_lite_idle_ns,
121 						   ddrcon_mhz), 1024),
122 			  RK3399_SET_ODT_PD_1_SRPD_LITE_IDLE);
123 
124 	if (dmcfreq->regmap_pmu) {
125 		if (target_rate >= dmcfreq->sr_idle_dis_freq)
126 			odt_pd_arg0 &= ~RK3399_SET_ODT_PD_0_SR_IDLE;
127 
128 		if (target_rate >= dmcfreq->sr_mc_gate_idle_dis_freq)
129 			odt_pd_arg0 &= ~RK3399_SET_ODT_PD_0_SR_MC_GATE_IDLE;
130 
131 		if (target_rate >= dmcfreq->standby_idle_dis_freq)
132 			odt_pd_arg0 &= ~RK3399_SET_ODT_PD_0_STANDBY_IDLE;
133 
134 		if (target_rate >= dmcfreq->pd_idle_dis_freq)
135 			odt_pd_arg1 &= ~RK3399_SET_ODT_PD_1_PD_IDLE;
136 
137 		if (target_rate >= dmcfreq->srpd_lite_idle_dis_freq)
138 			odt_pd_arg1 &= ~RK3399_SET_ODT_PD_1_SRPD_LITE_IDLE;
139 
140 		if (target_rate >= dmcfreq->odt_dis_freq)
141 			odt_pd_arg2 |= RK3399_SET_ODT_PD_2_ODT_ENABLE;
142 
143 		/*
144 		 * This makes a SMC call to the TF-A to set the DDR PD
145 		 * (power-down) timings and to enable or disable the
146 		 * ODT (on-die termination) resistors.
147 		 */
148 		arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, odt_pd_arg0, odt_pd_arg1,
149 			      ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD, odt_pd_arg2,
150 			      0, 0, 0, &res);
151 	}
152 
153 	/*
154 	 * If frequency scaling from low to high, adjust voltage first.
155 	 * If frequency scaling from high to low, adjust frequency first.
156 	 */
157 	if (old_clk_rate < target_rate) {
158 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
159 					    target_volt);
160 		if (err) {
161 			dev_err(dev, "Cannot set voltage %lu uV\n",
162 				target_volt);
163 			goto out;
164 		}
165 	}
166 
167 	err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
168 	if (err) {
169 		dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
170 			err);
171 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
172 				      dmcfreq->volt);
173 		goto out;
174 	}
175 
176 	/*
177 	 * Check the dpll rate,
178 	 * There only two result we will get,
179 	 * 1. Ddr frequency scaling fail, we still get the old rate.
180 	 * 2. Ddr frequency scaling sucessful, we get the rate we set.
181 	 */
182 	dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
183 
184 	/* If get the incorrect rate, set voltage to old value. */
185 	if (dmcfreq->rate != target_rate) {
186 		dev_err(dev, "Got wrong frequency, Request %lu, Current %lu\n",
187 			target_rate, dmcfreq->rate);
188 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
189 				      dmcfreq->volt);
190 		goto out;
191 	} else if (old_clk_rate > target_rate)
192 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
193 					    target_volt);
194 	if (err)
195 		dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
196 
197 	dmcfreq->rate = target_rate;
198 	dmcfreq->volt = target_volt;
199 
200 out:
201 	mutex_unlock(&dmcfreq->lock);
202 	return err;
203 }
204 
205 static int rk3399_dmcfreq_get_dev_status(struct device *dev,
206 					 struct devfreq_dev_status *stat)
207 {
208 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
209 	struct devfreq_event_data edata;
210 	int ret = 0;
211 
212 	ret = devfreq_event_get_event(dmcfreq->edev, &edata);
213 	if (ret < 0)
214 		return ret;
215 
216 	stat->current_frequency = dmcfreq->rate;
217 	stat->busy_time = edata.load_count;
218 	stat->total_time = edata.total_count;
219 
220 	return ret;
221 }
222 
223 static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
224 {
225 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
226 
227 	*freq = dmcfreq->rate;
228 
229 	return 0;
230 }
231 
232 static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
233 {
234 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
235 	int ret = 0;
236 
237 	ret = devfreq_event_disable_edev(dmcfreq->edev);
238 	if (ret < 0) {
239 		dev_err(dev, "failed to disable the devfreq-event devices\n");
240 		return ret;
241 	}
242 
243 	ret = devfreq_suspend_device(dmcfreq->devfreq);
244 	if (ret < 0) {
245 		dev_err(dev, "failed to suspend the devfreq devices\n");
246 		return ret;
247 	}
248 
249 	return 0;
250 }
251 
252 static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
253 {
254 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
255 	int ret = 0;
256 
257 	ret = devfreq_event_enable_edev(dmcfreq->edev);
258 	if (ret < 0) {
259 		dev_err(dev, "failed to enable the devfreq-event devices\n");
260 		return ret;
261 	}
262 
263 	ret = devfreq_resume_device(dmcfreq->devfreq);
264 	if (ret < 0) {
265 		dev_err(dev, "failed to resume the devfreq devices\n");
266 		return ret;
267 	}
268 	return ret;
269 }
270 
271 static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
272 			 rk3399_dmcfreq_resume);
273 
274 static int rk3399_dmcfreq_of_props(struct rk3399_dmcfreq *data,
275 				   struct device_node *np)
276 {
277 	int ret = 0;
278 
279 	/*
280 	 * These are all optional, and serve as minimum bounds. Give them large
281 	 * (i.e., never "disabled") values if the DT doesn't specify one.
282 	 */
283 	data->pd_idle_dis_freq =
284 		data->sr_idle_dis_freq =
285 		data->sr_mc_gate_idle_dis_freq =
286 		data->srpd_lite_idle_dis_freq =
287 		data->standby_idle_dis_freq = UINT_MAX;
288 
289 	ret |= of_property_read_u32(np, "rockchip,pd-idle-ns",
290 				    &data->pd_idle_ns);
291 	ret |= of_property_read_u32(np, "rockchip,sr-idle-ns",
292 				    &data->sr_idle_ns);
293 	ret |= of_property_read_u32(np, "rockchip,sr-mc-gate-idle-ns",
294 				    &data->sr_mc_gate_idle_ns);
295 	ret |= of_property_read_u32(np, "rockchip,srpd-lite-idle-ns",
296 				    &data->srpd_lite_idle_ns);
297 	ret |= of_property_read_u32(np, "rockchip,standby-idle-ns",
298 				    &data->standby_idle_ns);
299 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt_dis_freq",
300 				    &data->ddr3_odt_dis_freq);
301 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt_dis_freq",
302 				    &data->lpddr3_odt_dis_freq);
303 	ret |= of_property_read_u32(np, "rockchip,lpddr4_odt_dis_freq",
304 				    &data->lpddr4_odt_dis_freq);
305 
306 	ret |= of_property_read_u32(np, "rockchip,pd-idle-dis-freq-hz",
307 				    &data->pd_idle_dis_freq);
308 	ret |= of_property_read_u32(np, "rockchip,sr-idle-dis-freq-hz",
309 				    &data->sr_idle_dis_freq);
310 	ret |= of_property_read_u32(np, "rockchip,sr-mc-gate-idle-dis-freq-hz",
311 				    &data->sr_mc_gate_idle_dis_freq);
312 	ret |= of_property_read_u32(np, "rockchip,srpd-lite-idle-dis-freq-hz",
313 				    &data->srpd_lite_idle_dis_freq);
314 	ret |= of_property_read_u32(np, "rockchip,standby-idle-dis-freq-hz",
315 				    &data->standby_idle_dis_freq);
316 
317 	return ret;
318 }
319 
320 static int rk3399_dmcfreq_probe(struct platform_device *pdev)
321 {
322 	struct arm_smccc_res res;
323 	struct device *dev = &pdev->dev;
324 	struct device_node *np = pdev->dev.of_node, *node;
325 	struct rk3399_dmcfreq *data;
326 	int ret;
327 	struct dev_pm_opp *opp;
328 	u32 ddr_type;
329 	u32 val;
330 
331 	data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
332 	if (!data)
333 		return -ENOMEM;
334 
335 	mutex_init(&data->lock);
336 
337 	data->vdd_center = devm_regulator_get(dev, "center");
338 	if (IS_ERR(data->vdd_center))
339 		return dev_err_probe(dev, PTR_ERR(data->vdd_center),
340 				     "Cannot get the regulator \"center\"\n");
341 
342 	data->dmc_clk = devm_clk_get(dev, "dmc_clk");
343 	if (IS_ERR(data->dmc_clk))
344 		return dev_err_probe(dev, PTR_ERR(data->dmc_clk),
345 				     "Cannot get the clk dmc_clk\n");
346 
347 	data->edev = devfreq_event_get_edev_by_phandle(dev, "devfreq-events", 0);
348 	if (IS_ERR(data->edev))
349 		return -EPROBE_DEFER;
350 
351 	ret = devfreq_event_enable_edev(data->edev);
352 	if (ret < 0) {
353 		dev_err(dev, "failed to enable devfreq-event devices\n");
354 		return ret;
355 	}
356 
357 	rk3399_dmcfreq_of_props(data, np);
358 
359 	node = of_parse_phandle(np, "rockchip,pmu", 0);
360 	if (!node)
361 		goto no_pmu;
362 
363 	data->regmap_pmu = syscon_node_to_regmap(node);
364 	of_node_put(node);
365 	if (IS_ERR(data->regmap_pmu)) {
366 		ret = PTR_ERR(data->regmap_pmu);
367 		goto err_edev;
368 	}
369 
370 	regmap_read(data->regmap_pmu, RK3399_PMUGRF_OS_REG2, &val);
371 	ddr_type = (val >> RK3399_PMUGRF_DDRTYPE_SHIFT) &
372 		    RK3399_PMUGRF_DDRTYPE_MASK;
373 
374 	switch (ddr_type) {
375 	case RK3399_PMUGRF_DDRTYPE_DDR3:
376 		data->odt_dis_freq = data->ddr3_odt_dis_freq;
377 		break;
378 	case RK3399_PMUGRF_DDRTYPE_LPDDR3:
379 		data->odt_dis_freq = data->lpddr3_odt_dis_freq;
380 		break;
381 	case RK3399_PMUGRF_DDRTYPE_LPDDR4:
382 		data->odt_dis_freq = data->lpddr4_odt_dis_freq;
383 		break;
384 	default:
385 		ret = -EINVAL;
386 		goto err_edev;
387 	}
388 
389 no_pmu:
390 	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
391 		      ROCKCHIP_SIP_CONFIG_DRAM_INIT,
392 		      0, 0, 0, 0, &res);
393 
394 	/*
395 	 * We add a devfreq driver to our parent since it has a device tree node
396 	 * with operating points.
397 	 */
398 	if (devm_pm_opp_of_add_table(dev)) {
399 		dev_err(dev, "Invalid operating-points in device tree.\n");
400 		ret = -EINVAL;
401 		goto err_edev;
402 	}
403 
404 	data->ondemand_data.upthreshold = 25;
405 	data->ondemand_data.downdifferential = 15;
406 
407 	data->rate = clk_get_rate(data->dmc_clk);
408 
409 	opp = devfreq_recommended_opp(dev, &data->rate, 0);
410 	if (IS_ERR(opp)) {
411 		ret = PTR_ERR(opp);
412 		goto err_edev;
413 	}
414 
415 	data->rate = dev_pm_opp_get_freq(opp);
416 	data->volt = dev_pm_opp_get_voltage(opp);
417 	dev_pm_opp_put(opp);
418 
419 	data->profile = (struct devfreq_dev_profile) {
420 		.polling_ms	= 200,
421 		.target		= rk3399_dmcfreq_target,
422 		.get_dev_status	= rk3399_dmcfreq_get_dev_status,
423 		.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
424 		.initial_freq	= data->rate,
425 	};
426 
427 	data->devfreq = devm_devfreq_add_device(dev,
428 					   &data->profile,
429 					   DEVFREQ_GOV_SIMPLE_ONDEMAND,
430 					   &data->ondemand_data);
431 	if (IS_ERR(data->devfreq)) {
432 		ret = PTR_ERR(data->devfreq);
433 		goto err_edev;
434 	}
435 
436 	devm_devfreq_register_opp_notifier(dev, data->devfreq);
437 
438 	data->dev = dev;
439 	platform_set_drvdata(pdev, data);
440 
441 	return 0;
442 
443 err_edev:
444 	devfreq_event_disable_edev(data->edev);
445 
446 	return ret;
447 }
448 
449 static int rk3399_dmcfreq_remove(struct platform_device *pdev)
450 {
451 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(&pdev->dev);
452 
453 	devfreq_event_disable_edev(dmcfreq->edev);
454 
455 	return 0;
456 }
457 
458 static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
459 	{ .compatible = "rockchip,rk3399-dmc" },
460 	{ },
461 };
462 MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
463 
464 static struct platform_driver rk3399_dmcfreq_driver = {
465 	.probe	= rk3399_dmcfreq_probe,
466 	.remove = rk3399_dmcfreq_remove,
467 	.driver = {
468 		.name	= "rk3399-dmc-freq",
469 		.pm	= &rk3399_dmcfreq_pm,
470 		.of_match_table = rk3399dmc_devfreq_of_match,
471 	},
472 };
473 module_platform_driver(rk3399_dmcfreq_driver);
474 
475 MODULE_LICENSE("GPL v2");
476 MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
477 MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
478