xref: /openbmc/linux/drivers/devfreq/rk3399_dmc.c (revision 2cf1c348)
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/clk.h>
9 #include <linux/delay.h>
10 #include <linux/devfreq.h>
11 #include <linux/devfreq-event.h>
12 #include <linux/interrupt.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_opp.h>
18 #include <linux/regmap.h>
19 #include <linux/regulator/consumer.h>
20 #include <linux/rwsem.h>
21 #include <linux/suspend.h>
22 
23 #include <soc/rockchip/rk3399_grf.h>
24 #include <soc/rockchip/rockchip_sip.h>
25 
26 struct dram_timing {
27 	unsigned int ddr3_speed_bin;
28 	unsigned int pd_idle;
29 	unsigned int sr_idle;
30 	unsigned int sr_mc_gate_idle;
31 	unsigned int srpd_lite_idle;
32 	unsigned int standby_idle;
33 	unsigned int auto_pd_dis_freq;
34 	unsigned int dram_dll_dis_freq;
35 	unsigned int phy_dll_dis_freq;
36 	unsigned int ddr3_odt_dis_freq;
37 	unsigned int ddr3_drv;
38 	unsigned int ddr3_odt;
39 	unsigned int phy_ddr3_ca_drv;
40 	unsigned int phy_ddr3_dq_drv;
41 	unsigned int phy_ddr3_odt;
42 	unsigned int lpddr3_odt_dis_freq;
43 	unsigned int lpddr3_drv;
44 	unsigned int lpddr3_odt;
45 	unsigned int phy_lpddr3_ca_drv;
46 	unsigned int phy_lpddr3_dq_drv;
47 	unsigned int phy_lpddr3_odt;
48 	unsigned int lpddr4_odt_dis_freq;
49 	unsigned int lpddr4_drv;
50 	unsigned int lpddr4_dq_odt;
51 	unsigned int lpddr4_ca_odt;
52 	unsigned int phy_lpddr4_ca_drv;
53 	unsigned int phy_lpddr4_ck_cs_drv;
54 	unsigned int phy_lpddr4_dq_drv;
55 	unsigned int phy_lpddr4_odt;
56 };
57 
58 struct rk3399_dmcfreq {
59 	struct device *dev;
60 	struct devfreq *devfreq;
61 	struct devfreq_simple_ondemand_data ondemand_data;
62 	struct clk *dmc_clk;
63 	struct devfreq_event_dev *edev;
64 	struct mutex lock;
65 	struct dram_timing timing;
66 	struct regulator *vdd_center;
67 	struct regmap *regmap_pmu;
68 	unsigned long rate, target_rate;
69 	unsigned long volt, target_volt;
70 	unsigned int odt_dis_freq;
71 	int odt_pd_arg0, odt_pd_arg1;
72 };
73 
74 static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
75 				 u32 flags)
76 {
77 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
78 	struct dev_pm_opp *opp;
79 	unsigned long old_clk_rate = dmcfreq->rate;
80 	unsigned long target_volt, target_rate;
81 	struct arm_smccc_res res;
82 	bool odt_enable = false;
83 	int err;
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 	if (dmcfreq->regmap_pmu) {
99 		if (target_rate >= dmcfreq->odt_dis_freq)
100 			odt_enable = true;
101 
102 		/*
103 		 * This makes a SMC call to the TF-A to set the DDR PD
104 		 * (power-down) timings and to enable or disable the
105 		 * ODT (on-die termination) resistors.
106 		 */
107 		arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, dmcfreq->odt_pd_arg0,
108 			      dmcfreq->odt_pd_arg1,
109 			      ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD,
110 			      odt_enable, 0, 0, 0, &res);
111 	}
112 
113 	/*
114 	 * If frequency scaling from low to high, adjust voltage first.
115 	 * If frequency scaling from high to low, adjust frequency first.
116 	 */
117 	if (old_clk_rate < target_rate) {
118 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
119 					    target_volt);
120 		if (err) {
121 			dev_err(dev, "Cannot set voltage %lu uV\n",
122 				target_volt);
123 			goto out;
124 		}
125 	}
126 
127 	err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
128 	if (err) {
129 		dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
130 			err);
131 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
132 				      dmcfreq->volt);
133 		goto out;
134 	}
135 
136 	/*
137 	 * Check the dpll rate,
138 	 * There only two result we will get,
139 	 * 1. Ddr frequency scaling fail, we still get the old rate.
140 	 * 2. Ddr frequency scaling sucessful, we get the rate we set.
141 	 */
142 	dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
143 
144 	/* If get the incorrect rate, set voltage to old value. */
145 	if (dmcfreq->rate != target_rate) {
146 		dev_err(dev, "Got wrong frequency, Request %lu, Current %lu\n",
147 			target_rate, dmcfreq->rate);
148 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
149 				      dmcfreq->volt);
150 		goto out;
151 	} else if (old_clk_rate > target_rate)
152 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
153 					    target_volt);
154 	if (err)
155 		dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
156 
157 	dmcfreq->rate = target_rate;
158 	dmcfreq->volt = target_volt;
159 
160 out:
161 	mutex_unlock(&dmcfreq->lock);
162 	return err;
163 }
164 
165 static int rk3399_dmcfreq_get_dev_status(struct device *dev,
166 					 struct devfreq_dev_status *stat)
167 {
168 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
169 	struct devfreq_event_data edata;
170 	int ret = 0;
171 
172 	ret = devfreq_event_get_event(dmcfreq->edev, &edata);
173 	if (ret < 0)
174 		return ret;
175 
176 	stat->current_frequency = dmcfreq->rate;
177 	stat->busy_time = edata.load_count;
178 	stat->total_time = edata.total_count;
179 
180 	return ret;
181 }
182 
183 static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
184 {
185 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
186 
187 	*freq = dmcfreq->rate;
188 
189 	return 0;
190 }
191 
192 static struct devfreq_dev_profile rk3399_devfreq_dmc_profile = {
193 	.polling_ms	= 200,
194 	.target		= rk3399_dmcfreq_target,
195 	.get_dev_status	= rk3399_dmcfreq_get_dev_status,
196 	.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
197 };
198 
199 static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
200 {
201 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
202 	int ret = 0;
203 
204 	ret = devfreq_event_disable_edev(dmcfreq->edev);
205 	if (ret < 0) {
206 		dev_err(dev, "failed to disable the devfreq-event devices\n");
207 		return ret;
208 	}
209 
210 	ret = devfreq_suspend_device(dmcfreq->devfreq);
211 	if (ret < 0) {
212 		dev_err(dev, "failed to suspend the devfreq devices\n");
213 		return ret;
214 	}
215 
216 	return 0;
217 }
218 
219 static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
220 {
221 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
222 	int ret = 0;
223 
224 	ret = devfreq_event_enable_edev(dmcfreq->edev);
225 	if (ret < 0) {
226 		dev_err(dev, "failed to enable the devfreq-event devices\n");
227 		return ret;
228 	}
229 
230 	ret = devfreq_resume_device(dmcfreq->devfreq);
231 	if (ret < 0) {
232 		dev_err(dev, "failed to resume the devfreq devices\n");
233 		return ret;
234 	}
235 	return ret;
236 }
237 
238 static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
239 			 rk3399_dmcfreq_resume);
240 
241 static int of_get_ddr_timings(struct dram_timing *timing,
242 			      struct device_node *np)
243 {
244 	int ret = 0;
245 
246 	ret = of_property_read_u32(np, "rockchip,ddr3_speed_bin",
247 				   &timing->ddr3_speed_bin);
248 	ret |= of_property_read_u32(np, "rockchip,pd_idle",
249 				    &timing->pd_idle);
250 	ret |= of_property_read_u32(np, "rockchip,sr_idle",
251 				    &timing->sr_idle);
252 	ret |= of_property_read_u32(np, "rockchip,sr_mc_gate_idle",
253 				    &timing->sr_mc_gate_idle);
254 	ret |= of_property_read_u32(np, "rockchip,srpd_lite_idle",
255 				    &timing->srpd_lite_idle);
256 	ret |= of_property_read_u32(np, "rockchip,standby_idle",
257 				    &timing->standby_idle);
258 	ret |= of_property_read_u32(np, "rockchip,auto_pd_dis_freq",
259 				    &timing->auto_pd_dis_freq);
260 	ret |= of_property_read_u32(np, "rockchip,dram_dll_dis_freq",
261 				    &timing->dram_dll_dis_freq);
262 	ret |= of_property_read_u32(np, "rockchip,phy_dll_dis_freq",
263 				    &timing->phy_dll_dis_freq);
264 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt_dis_freq",
265 				    &timing->ddr3_odt_dis_freq);
266 	ret |= of_property_read_u32(np, "rockchip,ddr3_drv",
267 				    &timing->ddr3_drv);
268 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt",
269 				    &timing->ddr3_odt);
270 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_ca_drv",
271 				    &timing->phy_ddr3_ca_drv);
272 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_dq_drv",
273 				    &timing->phy_ddr3_dq_drv);
274 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_odt",
275 				    &timing->phy_ddr3_odt);
276 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt_dis_freq",
277 				    &timing->lpddr3_odt_dis_freq);
278 	ret |= of_property_read_u32(np, "rockchip,lpddr3_drv",
279 				    &timing->lpddr3_drv);
280 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt",
281 				    &timing->lpddr3_odt);
282 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_ca_drv",
283 				    &timing->phy_lpddr3_ca_drv);
284 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_dq_drv",
285 				    &timing->phy_lpddr3_dq_drv);
286 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_odt",
287 				    &timing->phy_lpddr3_odt);
288 	ret |= of_property_read_u32(np, "rockchip,lpddr4_odt_dis_freq",
289 				    &timing->lpddr4_odt_dis_freq);
290 	ret |= of_property_read_u32(np, "rockchip,lpddr4_drv",
291 				    &timing->lpddr4_drv);
292 	ret |= of_property_read_u32(np, "rockchip,lpddr4_dq_odt",
293 				    &timing->lpddr4_dq_odt);
294 	ret |= of_property_read_u32(np, "rockchip,lpddr4_ca_odt",
295 				    &timing->lpddr4_ca_odt);
296 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ca_drv",
297 				    &timing->phy_lpddr4_ca_drv);
298 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ck_cs_drv",
299 				    &timing->phy_lpddr4_ck_cs_drv);
300 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_dq_drv",
301 				    &timing->phy_lpddr4_dq_drv);
302 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_odt",
303 				    &timing->phy_lpddr4_odt);
304 
305 	return ret;
306 }
307 
308 static int rk3399_dmcfreq_probe(struct platform_device *pdev)
309 {
310 	struct arm_smccc_res res;
311 	struct device *dev = &pdev->dev;
312 	struct device_node *np = pdev->dev.of_node, *node;
313 	struct rk3399_dmcfreq *data;
314 	int ret, index, size;
315 	uint32_t *timing;
316 	struct dev_pm_opp *opp;
317 	u32 ddr_type;
318 	u32 val;
319 
320 	data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
321 	if (!data)
322 		return -ENOMEM;
323 
324 	mutex_init(&data->lock);
325 
326 	data->vdd_center = devm_regulator_get(dev, "center");
327 	if (IS_ERR(data->vdd_center))
328 		return dev_err_probe(dev, PTR_ERR(data->vdd_center),
329 				     "Cannot get the regulator \"center\"\n");
330 
331 	data->dmc_clk = devm_clk_get(dev, "dmc_clk");
332 	if (IS_ERR(data->dmc_clk))
333 		return dev_err_probe(dev, PTR_ERR(data->dmc_clk),
334 				     "Cannot get the clk dmc_clk\n");
335 
336 	data->edev = devfreq_event_get_edev_by_phandle(dev, "devfreq-events", 0);
337 	if (IS_ERR(data->edev))
338 		return -EPROBE_DEFER;
339 
340 	ret = devfreq_event_enable_edev(data->edev);
341 	if (ret < 0) {
342 		dev_err(dev, "failed to enable devfreq-event devices\n");
343 		return ret;
344 	}
345 
346 	/*
347 	 * Get dram timing and pass it to arm trust firmware,
348 	 * the dram driver in arm trust firmware will get these
349 	 * timing and to do dram initial.
350 	 */
351 	if (!of_get_ddr_timings(&data->timing, np)) {
352 		timing = &data->timing.ddr3_speed_bin;
353 		size = sizeof(struct dram_timing) / 4;
354 		for (index = 0; index < size; index++) {
355 			arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, *timing++, index,
356 				      ROCKCHIP_SIP_CONFIG_DRAM_SET_PARAM,
357 				      0, 0, 0, 0, &res);
358 			if (res.a0) {
359 				dev_err(dev, "Failed to set dram param: %ld\n",
360 					res.a0);
361 				ret = -EINVAL;
362 				goto err_edev;
363 			}
364 		}
365 	}
366 
367 	node = of_parse_phandle(np, "rockchip,pmu", 0);
368 	if (!node)
369 		goto no_pmu;
370 
371 	data->regmap_pmu = syscon_node_to_regmap(node);
372 	of_node_put(node);
373 	if (IS_ERR(data->regmap_pmu)) {
374 		ret = PTR_ERR(data->regmap_pmu);
375 		goto err_edev;
376 	}
377 
378 	regmap_read(data->regmap_pmu, RK3399_PMUGRF_OS_REG2, &val);
379 	ddr_type = (val >> RK3399_PMUGRF_DDRTYPE_SHIFT) &
380 		    RK3399_PMUGRF_DDRTYPE_MASK;
381 
382 	switch (ddr_type) {
383 	case RK3399_PMUGRF_DDRTYPE_DDR3:
384 		data->odt_dis_freq = data->timing.ddr3_odt_dis_freq;
385 		break;
386 	case RK3399_PMUGRF_DDRTYPE_LPDDR3:
387 		data->odt_dis_freq = data->timing.lpddr3_odt_dis_freq;
388 		break;
389 	case RK3399_PMUGRF_DDRTYPE_LPDDR4:
390 		data->odt_dis_freq = data->timing.lpddr4_odt_dis_freq;
391 		break;
392 	default:
393 		ret = -EINVAL;
394 		goto err_edev;
395 	}
396 
397 no_pmu:
398 	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
399 		      ROCKCHIP_SIP_CONFIG_DRAM_INIT,
400 		      0, 0, 0, 0, &res);
401 
402 	/*
403 	 * In TF-A there is a platform SIP call to set the PD (power-down)
404 	 * timings and to enable or disable the ODT (on-die termination).
405 	 * This call needs three arguments as follows:
406 	 *
407 	 * arg0:
408 	 *     bit[0-7]   : sr_idle
409 	 *     bit[8-15]  : sr_mc_gate_idle
410 	 *     bit[16-31] : standby idle
411 	 * arg1:
412 	 *     bit[0-11]  : pd_idle
413 	 *     bit[16-27] : srpd_lite_idle
414 	 * arg2:
415 	 *     bit[0]     : odt enable
416 	 */
417 	data->odt_pd_arg0 = (data->timing.sr_idle & 0xff) |
418 			    ((data->timing.sr_mc_gate_idle & 0xff) << 8) |
419 			    ((data->timing.standby_idle & 0xffff) << 16);
420 	data->odt_pd_arg1 = (data->timing.pd_idle & 0xfff) |
421 			    ((data->timing.srpd_lite_idle & 0xfff) << 16);
422 
423 	/*
424 	 * We add a devfreq driver to our parent since it has a device tree node
425 	 * with operating points.
426 	 */
427 	if (dev_pm_opp_of_add_table(dev)) {
428 		dev_err(dev, "Invalid operating-points in device tree.\n");
429 		ret = -EINVAL;
430 		goto err_edev;
431 	}
432 
433 	of_property_read_u32(np, "upthreshold",
434 			     &data->ondemand_data.upthreshold);
435 	of_property_read_u32(np, "downdifferential",
436 			     &data->ondemand_data.downdifferential);
437 
438 	data->rate = clk_get_rate(data->dmc_clk);
439 
440 	opp = devfreq_recommended_opp(dev, &data->rate, 0);
441 	if (IS_ERR(opp)) {
442 		ret = PTR_ERR(opp);
443 		goto err_free_opp;
444 	}
445 
446 	data->rate = dev_pm_opp_get_freq(opp);
447 	data->volt = dev_pm_opp_get_voltage(opp);
448 	dev_pm_opp_put(opp);
449 
450 	rk3399_devfreq_dmc_profile.initial_freq = data->rate;
451 
452 	data->devfreq = devm_devfreq_add_device(dev,
453 					   &rk3399_devfreq_dmc_profile,
454 					   DEVFREQ_GOV_SIMPLE_ONDEMAND,
455 					   &data->ondemand_data);
456 	if (IS_ERR(data->devfreq)) {
457 		ret = PTR_ERR(data->devfreq);
458 		goto err_free_opp;
459 	}
460 
461 	devm_devfreq_register_opp_notifier(dev, data->devfreq);
462 
463 	data->dev = dev;
464 	platform_set_drvdata(pdev, data);
465 
466 	return 0;
467 
468 err_free_opp:
469 	dev_pm_opp_of_remove_table(&pdev->dev);
470 err_edev:
471 	devfreq_event_disable_edev(data->edev);
472 
473 	return ret;
474 }
475 
476 static int rk3399_dmcfreq_remove(struct platform_device *pdev)
477 {
478 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(&pdev->dev);
479 
480 	/*
481 	 * Before remove the opp table we need to unregister the opp notifier.
482 	 */
483 	devm_devfreq_unregister_opp_notifier(dmcfreq->dev, dmcfreq->devfreq);
484 	dev_pm_opp_of_remove_table(dmcfreq->dev);
485 
486 	return 0;
487 }
488 
489 static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
490 	{ .compatible = "rockchip,rk3399-dmc" },
491 	{ },
492 };
493 MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
494 
495 static struct platform_driver rk3399_dmcfreq_driver = {
496 	.probe	= rk3399_dmcfreq_probe,
497 	.remove = rk3399_dmcfreq_remove,
498 	.driver = {
499 		.name	= "rk3399-dmc-freq",
500 		.pm	= &rk3399_dmcfreq_pm,
501 		.of_match_table = rk3399dmc_devfreq_of_match,
502 	},
503 };
504 module_platform_driver(rk3399_dmcfreq_driver);
505 
506 MODULE_LICENSE("GPL v2");
507 MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
508 MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
509