xref: /openbmc/linux/drivers/devfreq/rk3399_dmc.c (revision 752beb5e)
1 /*
2  * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd.
3  * Author: Lin Huang <hl@rock-chips.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/arm-smccc.h>
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/devfreq.h>
19 #include <linux/devfreq-event.h>
20 #include <linux/interrupt.h>
21 #include <linux/mfd/syscon.h>
22 #include <linux/module.h>
23 #include <linux/of.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_opp.h>
26 #include <linux/regmap.h>
27 #include <linux/regulator/consumer.h>
28 #include <linux/rwsem.h>
29 #include <linux/suspend.h>
30 
31 #include <soc/rockchip/rk3399_grf.h>
32 #include <soc/rockchip/rockchip_sip.h>
33 
34 struct dram_timing {
35 	unsigned int ddr3_speed_bin;
36 	unsigned int pd_idle;
37 	unsigned int sr_idle;
38 	unsigned int sr_mc_gate_idle;
39 	unsigned int srpd_lite_idle;
40 	unsigned int standby_idle;
41 	unsigned int auto_pd_dis_freq;
42 	unsigned int dram_dll_dis_freq;
43 	unsigned int phy_dll_dis_freq;
44 	unsigned int ddr3_odt_dis_freq;
45 	unsigned int ddr3_drv;
46 	unsigned int ddr3_odt;
47 	unsigned int phy_ddr3_ca_drv;
48 	unsigned int phy_ddr3_dq_drv;
49 	unsigned int phy_ddr3_odt;
50 	unsigned int lpddr3_odt_dis_freq;
51 	unsigned int lpddr3_drv;
52 	unsigned int lpddr3_odt;
53 	unsigned int phy_lpddr3_ca_drv;
54 	unsigned int phy_lpddr3_dq_drv;
55 	unsigned int phy_lpddr3_odt;
56 	unsigned int lpddr4_odt_dis_freq;
57 	unsigned int lpddr4_drv;
58 	unsigned int lpddr4_dq_odt;
59 	unsigned int lpddr4_ca_odt;
60 	unsigned int phy_lpddr4_ca_drv;
61 	unsigned int phy_lpddr4_ck_cs_drv;
62 	unsigned int phy_lpddr4_dq_drv;
63 	unsigned int phy_lpddr4_odt;
64 };
65 
66 struct rk3399_dmcfreq {
67 	struct device *dev;
68 	struct devfreq *devfreq;
69 	struct devfreq_simple_ondemand_data ondemand_data;
70 	struct clk *dmc_clk;
71 	struct devfreq_event_dev *edev;
72 	struct mutex lock;
73 	struct dram_timing timing;
74 	struct regulator *vdd_center;
75 	struct regmap *regmap_pmu;
76 	unsigned long rate, target_rate;
77 	unsigned long volt, target_volt;
78 	unsigned int odt_dis_freq;
79 	int odt_pd_arg0, odt_pd_arg1;
80 };
81 
82 static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
83 				 u32 flags)
84 {
85 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
86 	struct dev_pm_opp *opp;
87 	unsigned long old_clk_rate = dmcfreq->rate;
88 	unsigned long target_volt, target_rate;
89 	struct arm_smccc_res res;
90 	bool odt_enable = false;
91 	int err;
92 
93 	opp = devfreq_recommended_opp(dev, freq, flags);
94 	if (IS_ERR(opp))
95 		return PTR_ERR(opp);
96 
97 	target_rate = dev_pm_opp_get_freq(opp);
98 	target_volt = dev_pm_opp_get_voltage(opp);
99 	dev_pm_opp_put(opp);
100 
101 	if (dmcfreq->rate == target_rate)
102 		return 0;
103 
104 	mutex_lock(&dmcfreq->lock);
105 
106 	if (target_rate >= dmcfreq->odt_dis_freq)
107 		odt_enable = true;
108 
109 	/*
110 	 * This makes a SMC call to the TF-A to set the DDR PD (power-down)
111 	 * timings and to enable or disable the ODT (on-die termination)
112 	 * resistors.
113 	 */
114 	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, dmcfreq->odt_pd_arg0,
115 		      dmcfreq->odt_pd_arg1,
116 		      ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD,
117 		      odt_enable, 0, 0, 0, &res);
118 
119 	/*
120 	 * If frequency scaling from low to high, adjust voltage first.
121 	 * If frequency scaling from high to low, adjust frequency first.
122 	 */
123 	if (old_clk_rate < target_rate) {
124 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
125 					    target_volt);
126 		if (err) {
127 			dev_err(dev, "Cannot set voltage %lu uV\n",
128 				target_volt);
129 			goto out;
130 		}
131 	}
132 
133 	err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
134 	if (err) {
135 		dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
136 			err);
137 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
138 				      dmcfreq->volt);
139 		goto out;
140 	}
141 
142 	/*
143 	 * Check the dpll rate,
144 	 * There only two result we will get,
145 	 * 1. Ddr frequency scaling fail, we still get the old rate.
146 	 * 2. Ddr frequency scaling sucessful, we get the rate we set.
147 	 */
148 	dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
149 
150 	/* If get the incorrect rate, set voltage to old value. */
151 	if (dmcfreq->rate != target_rate) {
152 		dev_err(dev, "Got wrong frequency, Request %lu, Current %lu\n",
153 			target_rate, dmcfreq->rate);
154 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
155 				      dmcfreq->volt);
156 		goto out;
157 	} else 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", target_volt);
162 
163 	dmcfreq->rate = target_rate;
164 	dmcfreq->volt = target_volt;
165 
166 out:
167 	mutex_unlock(&dmcfreq->lock);
168 	return err;
169 }
170 
171 static int rk3399_dmcfreq_get_dev_status(struct device *dev,
172 					 struct devfreq_dev_status *stat)
173 {
174 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
175 	struct devfreq_event_data edata;
176 	int ret = 0;
177 
178 	ret = devfreq_event_get_event(dmcfreq->edev, &edata);
179 	if (ret < 0)
180 		return ret;
181 
182 	stat->current_frequency = dmcfreq->rate;
183 	stat->busy_time = edata.load_count;
184 	stat->total_time = edata.total_count;
185 
186 	return ret;
187 }
188 
189 static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
190 {
191 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
192 
193 	*freq = dmcfreq->rate;
194 
195 	return 0;
196 }
197 
198 static struct devfreq_dev_profile rk3399_devfreq_dmc_profile = {
199 	.polling_ms	= 200,
200 	.target		= rk3399_dmcfreq_target,
201 	.get_dev_status	= rk3399_dmcfreq_get_dev_status,
202 	.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
203 };
204 
205 static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
206 {
207 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
208 	int ret = 0;
209 
210 	ret = devfreq_event_disable_edev(dmcfreq->edev);
211 	if (ret < 0) {
212 		dev_err(dev, "failed to disable the devfreq-event devices\n");
213 		return ret;
214 	}
215 
216 	ret = devfreq_suspend_device(dmcfreq->devfreq);
217 	if (ret < 0) {
218 		dev_err(dev, "failed to suspend the devfreq devices\n");
219 		return ret;
220 	}
221 
222 	return 0;
223 }
224 
225 static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
226 {
227 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
228 	int ret = 0;
229 
230 	ret = devfreq_event_enable_edev(dmcfreq->edev);
231 	if (ret < 0) {
232 		dev_err(dev, "failed to enable the devfreq-event devices\n");
233 		return ret;
234 	}
235 
236 	ret = devfreq_resume_device(dmcfreq->devfreq);
237 	if (ret < 0) {
238 		dev_err(dev, "failed to resume the devfreq devices\n");
239 		return ret;
240 	}
241 	return ret;
242 }
243 
244 static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
245 			 rk3399_dmcfreq_resume);
246 
247 static int of_get_ddr_timings(struct dram_timing *timing,
248 			      struct device_node *np)
249 {
250 	int ret = 0;
251 
252 	ret = of_property_read_u32(np, "rockchip,ddr3_speed_bin",
253 				   &timing->ddr3_speed_bin);
254 	ret |= of_property_read_u32(np, "rockchip,pd_idle",
255 				    &timing->pd_idle);
256 	ret |= of_property_read_u32(np, "rockchip,sr_idle",
257 				    &timing->sr_idle);
258 	ret |= of_property_read_u32(np, "rockchip,sr_mc_gate_idle",
259 				    &timing->sr_mc_gate_idle);
260 	ret |= of_property_read_u32(np, "rockchip,srpd_lite_idle",
261 				    &timing->srpd_lite_idle);
262 	ret |= of_property_read_u32(np, "rockchip,standby_idle",
263 				    &timing->standby_idle);
264 	ret |= of_property_read_u32(np, "rockchip,auto_pd_dis_freq",
265 				    &timing->auto_pd_dis_freq);
266 	ret |= of_property_read_u32(np, "rockchip,dram_dll_dis_freq",
267 				    &timing->dram_dll_dis_freq);
268 	ret |= of_property_read_u32(np, "rockchip,phy_dll_dis_freq",
269 				    &timing->phy_dll_dis_freq);
270 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt_dis_freq",
271 				    &timing->ddr3_odt_dis_freq);
272 	ret |= of_property_read_u32(np, "rockchip,ddr3_drv",
273 				    &timing->ddr3_drv);
274 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt",
275 				    &timing->ddr3_odt);
276 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_ca_drv",
277 				    &timing->phy_ddr3_ca_drv);
278 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_dq_drv",
279 				    &timing->phy_ddr3_dq_drv);
280 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_odt",
281 				    &timing->phy_ddr3_odt);
282 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt_dis_freq",
283 				    &timing->lpddr3_odt_dis_freq);
284 	ret |= of_property_read_u32(np, "rockchip,lpddr3_drv",
285 				    &timing->lpddr3_drv);
286 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt",
287 				    &timing->lpddr3_odt);
288 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_ca_drv",
289 				    &timing->phy_lpddr3_ca_drv);
290 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_dq_drv",
291 				    &timing->phy_lpddr3_dq_drv);
292 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_odt",
293 				    &timing->phy_lpddr3_odt);
294 	ret |= of_property_read_u32(np, "rockchip,lpddr4_odt_dis_freq",
295 				    &timing->lpddr4_odt_dis_freq);
296 	ret |= of_property_read_u32(np, "rockchip,lpddr4_drv",
297 				    &timing->lpddr4_drv);
298 	ret |= of_property_read_u32(np, "rockchip,lpddr4_dq_odt",
299 				    &timing->lpddr4_dq_odt);
300 	ret |= of_property_read_u32(np, "rockchip,lpddr4_ca_odt",
301 				    &timing->lpddr4_ca_odt);
302 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ca_drv",
303 				    &timing->phy_lpddr4_ca_drv);
304 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ck_cs_drv",
305 				    &timing->phy_lpddr4_ck_cs_drv);
306 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_dq_drv",
307 				    &timing->phy_lpddr4_dq_drv);
308 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_odt",
309 				    &timing->phy_lpddr4_odt);
310 
311 	return ret;
312 }
313 
314 static int rk3399_dmcfreq_probe(struct platform_device *pdev)
315 {
316 	struct arm_smccc_res res;
317 	struct device *dev = &pdev->dev;
318 	struct device_node *np = pdev->dev.of_node, *node;
319 	struct rk3399_dmcfreq *data;
320 	int ret, index, size;
321 	uint32_t *timing;
322 	struct dev_pm_opp *opp;
323 	u32 ddr_type;
324 	u32 val;
325 
326 	data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
327 	if (!data)
328 		return -ENOMEM;
329 
330 	mutex_init(&data->lock);
331 
332 	data->vdd_center = devm_regulator_get(dev, "center");
333 	if (IS_ERR(data->vdd_center)) {
334 		if (PTR_ERR(data->vdd_center) == -EPROBE_DEFER)
335 			return -EPROBE_DEFER;
336 
337 		dev_err(dev, "Cannot get the regulator \"center\"\n");
338 		return PTR_ERR(data->vdd_center);
339 	}
340 
341 	data->dmc_clk = devm_clk_get(dev, "dmc_clk");
342 	if (IS_ERR(data->dmc_clk)) {
343 		if (PTR_ERR(data->dmc_clk) == -EPROBE_DEFER)
344 			return -EPROBE_DEFER;
345 
346 		dev_err(dev, "Cannot get the clk dmc_clk\n");
347 		return PTR_ERR(data->dmc_clk);
348 	}
349 
350 	data->edev = devfreq_event_get_edev_by_phandle(dev, 0);
351 	if (IS_ERR(data->edev))
352 		return -EPROBE_DEFER;
353 
354 	ret = devfreq_event_enable_edev(data->edev);
355 	if (ret < 0) {
356 		dev_err(dev, "failed to enable devfreq-event devices\n");
357 		return ret;
358 	}
359 
360 	/*
361 	 * Get dram timing and pass it to arm trust firmware,
362 	 * the dram drvier in arm trust firmware will get these
363 	 * timing and to do dram initial.
364 	 */
365 	if (!of_get_ddr_timings(&data->timing, np)) {
366 		timing = &data->timing.ddr3_speed_bin;
367 		size = sizeof(struct dram_timing) / 4;
368 		for (index = 0; index < size; index++) {
369 			arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, *timing++, index,
370 				      ROCKCHIP_SIP_CONFIG_DRAM_SET_PARAM,
371 				      0, 0, 0, 0, &res);
372 			if (res.a0) {
373 				dev_err(dev, "Failed to set dram param: %ld\n",
374 					res.a0);
375 				return -EINVAL;
376 			}
377 		}
378 	}
379 
380 	node = of_parse_phandle(np, "rockchip,pmu", 0);
381 	if (node) {
382 		data->regmap_pmu = syscon_node_to_regmap(node);
383 		if (IS_ERR(data->regmap_pmu))
384 			return PTR_ERR(data->regmap_pmu);
385 	}
386 
387 	regmap_read(data->regmap_pmu, RK3399_PMUGRF_OS_REG2, &val);
388 	ddr_type = (val >> RK3399_PMUGRF_DDRTYPE_SHIFT) &
389 		    RK3399_PMUGRF_DDRTYPE_MASK;
390 
391 	switch (ddr_type) {
392 	case RK3399_PMUGRF_DDRTYPE_DDR3:
393 		data->odt_dis_freq = data->timing.ddr3_odt_dis_freq;
394 		break;
395 	case RK3399_PMUGRF_DDRTYPE_LPDDR3:
396 		data->odt_dis_freq = data->timing.lpddr3_odt_dis_freq;
397 		break;
398 	case RK3399_PMUGRF_DDRTYPE_LPDDR4:
399 		data->odt_dis_freq = data->timing.lpddr4_odt_dis_freq;
400 		break;
401 	default:
402 		return -EINVAL;
403 	};
404 
405 	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
406 		      ROCKCHIP_SIP_CONFIG_DRAM_INIT,
407 		      0, 0, 0, 0, &res);
408 
409 	/*
410 	 * In TF-A there is a platform SIP call to set the PD (power-down)
411 	 * timings and to enable or disable the ODT (on-die termination).
412 	 * This call needs three arguments as follows:
413 	 *
414 	 * arg0:
415 	 *     bit[0-7]   : sr_idle
416 	 *     bit[8-15]  : sr_mc_gate_idle
417 	 *     bit[16-31] : standby idle
418 	 * arg1:
419 	 *     bit[0-11]  : pd_idle
420 	 *     bit[16-27] : srpd_lite_idle
421 	 * arg2:
422 	 *     bit[0]     : odt enable
423 	 */
424 	data->odt_pd_arg0 = (data->timing.sr_idle & 0xff) |
425 			    ((data->timing.sr_mc_gate_idle & 0xff) << 8) |
426 			    ((data->timing.standby_idle & 0xffff) << 16);
427 	data->odt_pd_arg1 = (data->timing.pd_idle & 0xfff) |
428 			    ((data->timing.srpd_lite_idle & 0xfff) << 16);
429 
430 	/*
431 	 * We add a devfreq driver to our parent since it has a device tree node
432 	 * with operating points.
433 	 */
434 	if (dev_pm_opp_of_add_table(dev)) {
435 		dev_err(dev, "Invalid operating-points in device tree.\n");
436 		return -EINVAL;
437 	}
438 
439 	of_property_read_u32(np, "upthreshold",
440 			     &data->ondemand_data.upthreshold);
441 	of_property_read_u32(np, "downdifferential",
442 			     &data->ondemand_data.downdifferential);
443 
444 	data->rate = clk_get_rate(data->dmc_clk);
445 
446 	opp = devfreq_recommended_opp(dev, &data->rate, 0);
447 	if (IS_ERR(opp)) {
448 		ret = PTR_ERR(opp);
449 		goto err_free_opp;
450 	}
451 
452 	data->rate = dev_pm_opp_get_freq(opp);
453 	data->volt = dev_pm_opp_get_voltage(opp);
454 	dev_pm_opp_put(opp);
455 
456 	rk3399_devfreq_dmc_profile.initial_freq = data->rate;
457 
458 	data->devfreq = devm_devfreq_add_device(dev,
459 					   &rk3399_devfreq_dmc_profile,
460 					   DEVFREQ_GOV_SIMPLE_ONDEMAND,
461 					   &data->ondemand_data);
462 	if (IS_ERR(data->devfreq)) {
463 		ret = PTR_ERR(data->devfreq);
464 		goto err_free_opp;
465 	}
466 
467 	devm_devfreq_register_opp_notifier(dev, data->devfreq);
468 
469 	data->dev = dev;
470 	platform_set_drvdata(pdev, data);
471 
472 	return 0;
473 
474 err_free_opp:
475 	dev_pm_opp_of_remove_table(&pdev->dev);
476 	return ret;
477 }
478 
479 static int rk3399_dmcfreq_remove(struct platform_device *pdev)
480 {
481 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(&pdev->dev);
482 
483 	/*
484 	 * Before remove the opp table we need to unregister the opp notifier.
485 	 */
486 	devm_devfreq_unregister_opp_notifier(dmcfreq->dev, dmcfreq->devfreq);
487 	dev_pm_opp_of_remove_table(dmcfreq->dev);
488 
489 	return 0;
490 }
491 
492 static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
493 	{ .compatible = "rockchip,rk3399-dmc" },
494 	{ },
495 };
496 MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
497 
498 static struct platform_driver rk3399_dmcfreq_driver = {
499 	.probe	= rk3399_dmcfreq_probe,
500 	.remove = rk3399_dmcfreq_remove,
501 	.driver = {
502 		.name	= "rk3399-dmc-freq",
503 		.pm	= &rk3399_dmcfreq_pm,
504 		.of_match_table = rk3399dmc_devfreq_of_match,
505 	},
506 };
507 module_platform_driver(rk3399_dmcfreq_driver);
508 
509 MODULE_LICENSE("GPL v2");
510 MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
511 MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
512