xref: /openbmc/linux/drivers/devfreq/rk3399_dmc.c (revision 8730046c)
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/module.h>
22 #include <linux/of.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_opp.h>
25 #include <linux/regulator/consumer.h>
26 #include <linux/rwsem.h>
27 #include <linux/suspend.h>
28 
29 #include <soc/rockchip/rockchip_sip.h>
30 
31 struct dram_timing {
32 	unsigned int ddr3_speed_bin;
33 	unsigned int pd_idle;
34 	unsigned int sr_idle;
35 	unsigned int sr_mc_gate_idle;
36 	unsigned int srpd_lite_idle;
37 	unsigned int standby_idle;
38 	unsigned int auto_pd_dis_freq;
39 	unsigned int dram_dll_dis_freq;
40 	unsigned int phy_dll_dis_freq;
41 	unsigned int ddr3_odt_dis_freq;
42 	unsigned int ddr3_drv;
43 	unsigned int ddr3_odt;
44 	unsigned int phy_ddr3_ca_drv;
45 	unsigned int phy_ddr3_dq_drv;
46 	unsigned int phy_ddr3_odt;
47 	unsigned int lpddr3_odt_dis_freq;
48 	unsigned int lpddr3_drv;
49 	unsigned int lpddr3_odt;
50 	unsigned int phy_lpddr3_ca_drv;
51 	unsigned int phy_lpddr3_dq_drv;
52 	unsigned int phy_lpddr3_odt;
53 	unsigned int lpddr4_odt_dis_freq;
54 	unsigned int lpddr4_drv;
55 	unsigned int lpddr4_dq_odt;
56 	unsigned int lpddr4_ca_odt;
57 	unsigned int phy_lpddr4_ca_drv;
58 	unsigned int phy_lpddr4_ck_cs_drv;
59 	unsigned int phy_lpddr4_dq_drv;
60 	unsigned int phy_lpddr4_odt;
61 };
62 
63 struct rk3399_dmcfreq {
64 	struct device *dev;
65 	struct devfreq *devfreq;
66 	struct devfreq_simple_ondemand_data ondemand_data;
67 	struct clk *dmc_clk;
68 	struct devfreq_event_dev *edev;
69 	struct mutex lock;
70 	struct dram_timing timing;
71 
72 	/*
73 	 * DDR Converser of Frequency (DCF) is used to implement DDR frequency
74 	 * conversion without the participation of CPU, we will implement and
75 	 * control it in arm trust firmware.
76 	 */
77 	wait_queue_head_t	wait_dcf_queue;
78 	int irq;
79 	int wait_dcf_flag;
80 	struct regulator *vdd_center;
81 	unsigned long rate, target_rate;
82 	unsigned long volt, target_volt;
83 };
84 
85 static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
86 				 u32 flags)
87 {
88 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
89 	struct dev_pm_opp *opp;
90 	unsigned long old_clk_rate = dmcfreq->rate;
91 	unsigned long target_volt, target_rate;
92 	int err;
93 
94 	rcu_read_lock();
95 	opp = devfreq_recommended_opp(dev, freq, flags);
96 	if (IS_ERR(opp)) {
97 		rcu_read_unlock();
98 		return PTR_ERR(opp);
99 	}
100 
101 	target_rate = dev_pm_opp_get_freq(opp);
102 	target_volt = dev_pm_opp_get_voltage(opp);
103 
104 	rcu_read_unlock();
105 
106 	if (dmcfreq->rate == target_rate)
107 		return 0;
108 
109 	mutex_lock(&dmcfreq->lock);
110 
111 	/*
112 	 * If frequency scaling from low to high, adjust voltage first.
113 	 * If frequency scaling from high to low, adjust frequency first.
114 	 */
115 	if (old_clk_rate < target_rate) {
116 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
117 					    target_volt);
118 		if (err) {
119 			dev_err(dev, "Cannot to set voltage %lu uV\n",
120 				target_volt);
121 			goto out;
122 		}
123 	}
124 	dmcfreq->wait_dcf_flag = 1;
125 
126 	err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
127 	if (err) {
128 		dev_err(dev, "Cannot to set frequency %lu (%d)\n",
129 			target_rate, err);
130 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
131 				      dmcfreq->volt);
132 		goto out;
133 	}
134 
135 	/*
136 	 * Wait until bcf irq happen, it means freq scaling finish in
137 	 * arm trust firmware, use 100ms as timeout time.
138 	 */
139 	if (!wait_event_timeout(dmcfreq->wait_dcf_queue,
140 				!dmcfreq->wait_dcf_flag, HZ / 10))
141 		dev_warn(dev, "Timeout waiting for dcf interrupt\n");
142 
143 	/*
144 	 * Check the dpll rate,
145 	 * There only two result we will get,
146 	 * 1. Ddr frequency scaling fail, we still get the old rate.
147 	 * 2. Ddr frequency scaling sucessful, we get the rate we set.
148 	 */
149 	dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
150 
151 	/* If get the incorrect rate, set voltage to old value. */
152 	if (dmcfreq->rate != target_rate) {
153 		dev_err(dev, "Get wrong ddr frequency, Request frequency %lu,\
154 			Current frequency %lu\n", target_rate, dmcfreq->rate);
155 		regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
156 				      dmcfreq->volt);
157 		goto out;
158 	} else if (old_clk_rate > target_rate)
159 		err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
160 					    target_volt);
161 	if (err)
162 		dev_err(dev, "Cannot to set vol %lu uV\n", target_volt);
163 
164 	dmcfreq->rate = target_rate;
165 	dmcfreq->volt = target_volt;
166 
167 out:
168 	mutex_unlock(&dmcfreq->lock);
169 	return err;
170 }
171 
172 static int rk3399_dmcfreq_get_dev_status(struct device *dev,
173 					 struct devfreq_dev_status *stat)
174 {
175 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
176 	struct devfreq_event_data edata;
177 	int ret = 0;
178 
179 	ret = devfreq_event_get_event(dmcfreq->edev, &edata);
180 	if (ret < 0)
181 		return ret;
182 
183 	stat->current_frequency = dmcfreq->rate;
184 	stat->busy_time = edata.load_count;
185 	stat->total_time = edata.total_count;
186 
187 	return ret;
188 }
189 
190 static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
191 {
192 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
193 
194 	*freq = dmcfreq->rate;
195 
196 	return 0;
197 }
198 
199 static struct devfreq_dev_profile rk3399_devfreq_dmc_profile = {
200 	.polling_ms	= 200,
201 	.target		= rk3399_dmcfreq_target,
202 	.get_dev_status	= rk3399_dmcfreq_get_dev_status,
203 	.get_cur_freq	= rk3399_dmcfreq_get_cur_freq,
204 };
205 
206 static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
207 {
208 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
209 	int ret = 0;
210 
211 	ret = devfreq_event_disable_edev(dmcfreq->edev);
212 	if (ret < 0) {
213 		dev_err(dev, "failed to disable the devfreq-event devices\n");
214 		return ret;
215 	}
216 
217 	ret = devfreq_suspend_device(dmcfreq->devfreq);
218 	if (ret < 0) {
219 		dev_err(dev, "failed to suspend the devfreq devices\n");
220 		return ret;
221 	}
222 
223 	return 0;
224 }
225 
226 static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
227 {
228 	struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
229 	int ret = 0;
230 
231 	ret = devfreq_event_enable_edev(dmcfreq->edev);
232 	if (ret < 0) {
233 		dev_err(dev, "failed to enable the devfreq-event devices\n");
234 		return ret;
235 	}
236 
237 	ret = devfreq_resume_device(dmcfreq->devfreq);
238 	if (ret < 0) {
239 		dev_err(dev, "failed to resume the devfreq devices\n");
240 		return ret;
241 	}
242 	return ret;
243 }
244 
245 static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
246 			 rk3399_dmcfreq_resume);
247 
248 static irqreturn_t rk3399_dmc_irq(int irq, void *dev_id)
249 {
250 	struct rk3399_dmcfreq *dmcfreq = dev_id;
251 	struct arm_smccc_res res;
252 
253 	dmcfreq->wait_dcf_flag = 0;
254 	wake_up(&dmcfreq->wait_dcf_queue);
255 
256 	/* Clear the DCF interrupt */
257 	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
258 		      ROCKCHIP_SIP_CONFIG_DRAM_CLR_IRQ,
259 		      0, 0, 0, 0, &res);
260 
261 	return IRQ_HANDLED;
262 }
263 
264 static int of_get_ddr_timings(struct dram_timing *timing,
265 			      struct device_node *np)
266 {
267 	int ret = 0;
268 
269 	ret = of_property_read_u32(np, "rockchip,ddr3_speed_bin",
270 				   &timing->ddr3_speed_bin);
271 	ret |= of_property_read_u32(np, "rockchip,pd_idle",
272 				    &timing->pd_idle);
273 	ret |= of_property_read_u32(np, "rockchip,sr_idle",
274 				    &timing->sr_idle);
275 	ret |= of_property_read_u32(np, "rockchip,sr_mc_gate_idle",
276 				    &timing->sr_mc_gate_idle);
277 	ret |= of_property_read_u32(np, "rockchip,srpd_lite_idle",
278 				    &timing->srpd_lite_idle);
279 	ret |= of_property_read_u32(np, "rockchip,standby_idle",
280 				    &timing->standby_idle);
281 	ret |= of_property_read_u32(np, "rockchip,auto_pd_dis_freq",
282 				    &timing->auto_pd_dis_freq);
283 	ret |= of_property_read_u32(np, "rockchip,dram_dll_dis_freq",
284 				    &timing->dram_dll_dis_freq);
285 	ret |= of_property_read_u32(np, "rockchip,phy_dll_dis_freq",
286 				    &timing->phy_dll_dis_freq);
287 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt_dis_freq",
288 				    &timing->ddr3_odt_dis_freq);
289 	ret |= of_property_read_u32(np, "rockchip,ddr3_drv",
290 				    &timing->ddr3_drv);
291 	ret |= of_property_read_u32(np, "rockchip,ddr3_odt",
292 				    &timing->ddr3_odt);
293 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_ca_drv",
294 				    &timing->phy_ddr3_ca_drv);
295 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_dq_drv",
296 				    &timing->phy_ddr3_dq_drv);
297 	ret |= of_property_read_u32(np, "rockchip,phy_ddr3_odt",
298 				    &timing->phy_ddr3_odt);
299 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt_dis_freq",
300 				    &timing->lpddr3_odt_dis_freq);
301 	ret |= of_property_read_u32(np, "rockchip,lpddr3_drv",
302 				    &timing->lpddr3_drv);
303 	ret |= of_property_read_u32(np, "rockchip,lpddr3_odt",
304 				    &timing->lpddr3_odt);
305 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_ca_drv",
306 				    &timing->phy_lpddr3_ca_drv);
307 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_dq_drv",
308 				    &timing->phy_lpddr3_dq_drv);
309 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_odt",
310 				    &timing->phy_lpddr3_odt);
311 	ret |= of_property_read_u32(np, "rockchip,lpddr4_odt_dis_freq",
312 				    &timing->lpddr4_odt_dis_freq);
313 	ret |= of_property_read_u32(np, "rockchip,lpddr4_drv",
314 				    &timing->lpddr4_drv);
315 	ret |= of_property_read_u32(np, "rockchip,lpddr4_dq_odt",
316 				    &timing->lpddr4_dq_odt);
317 	ret |= of_property_read_u32(np, "rockchip,lpddr4_ca_odt",
318 				    &timing->lpddr4_ca_odt);
319 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ca_drv",
320 				    &timing->phy_lpddr4_ca_drv);
321 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ck_cs_drv",
322 				    &timing->phy_lpddr4_ck_cs_drv);
323 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_dq_drv",
324 				    &timing->phy_lpddr4_dq_drv);
325 	ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_odt",
326 				    &timing->phy_lpddr4_odt);
327 
328 	return ret;
329 }
330 
331 static int rk3399_dmcfreq_probe(struct platform_device *pdev)
332 {
333 	struct arm_smccc_res res;
334 	struct device *dev = &pdev->dev;
335 	struct device_node *np = pdev->dev.of_node;
336 	struct rk3399_dmcfreq *data;
337 	int ret, irq, index, size;
338 	uint32_t *timing;
339 	struct dev_pm_opp *opp;
340 
341 	irq = platform_get_irq(pdev, 0);
342 	if (irq < 0) {
343 		dev_err(&pdev->dev, "Cannot get the dmc interrupt resource\n");
344 		return -EINVAL;
345 	}
346 	data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
347 	if (!data)
348 		return -ENOMEM;
349 
350 	mutex_init(&data->lock);
351 
352 	data->vdd_center = devm_regulator_get(dev, "center");
353 	if (IS_ERR(data->vdd_center)) {
354 		dev_err(dev, "Cannot get the regulator \"center\"\n");
355 		return PTR_ERR(data->vdd_center);
356 	}
357 
358 	data->dmc_clk = devm_clk_get(dev, "dmc_clk");
359 	if (IS_ERR(data->dmc_clk)) {
360 		dev_err(dev, "Cannot get the clk dmc_clk\n");
361 		return PTR_ERR(data->dmc_clk);
362 	};
363 
364 	data->irq = irq;
365 	ret = devm_request_irq(dev, irq, rk3399_dmc_irq, 0,
366 			       dev_name(dev), data);
367 	if (ret) {
368 		dev_err(dev, "Failed to request dmc irq: %d\n", ret);
369 		return ret;
370 	}
371 
372 	init_waitqueue_head(&data->wait_dcf_queue);
373 	data->wait_dcf_flag = 0;
374 
375 	data->edev = devfreq_event_get_edev_by_phandle(dev, 0);
376 	if (IS_ERR(data->edev))
377 		return -EPROBE_DEFER;
378 
379 	ret = devfreq_event_enable_edev(data->edev);
380 	if (ret < 0) {
381 		dev_err(dev, "failed to enable devfreq-event devices\n");
382 		return ret;
383 	}
384 
385 	/*
386 	 * Get dram timing and pass it to arm trust firmware,
387 	 * the dram drvier in arm trust firmware will get these
388 	 * timing and to do dram initial.
389 	 */
390 	if (!of_get_ddr_timings(&data->timing, np)) {
391 		timing = &data->timing.ddr3_speed_bin;
392 		size = sizeof(struct dram_timing) / 4;
393 		for (index = 0; index < size; index++) {
394 			arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, *timing++, index,
395 				      ROCKCHIP_SIP_CONFIG_DRAM_SET_PARAM,
396 				      0, 0, 0, 0, &res);
397 			if (res.a0) {
398 				dev_err(dev, "Failed to set dram param: %ld\n",
399 					res.a0);
400 				return -EINVAL;
401 			}
402 		}
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 	 * We add a devfreq driver to our parent since it has a device tree node
411 	 * with operating points.
412 	 */
413 	if (dev_pm_opp_of_add_table(dev)) {
414 		dev_err(dev, "Invalid operating-points in device tree.\n");
415 		return -EINVAL;
416 	}
417 
418 	of_property_read_u32(np, "upthreshold",
419 			     &data->ondemand_data.upthreshold);
420 	of_property_read_u32(np, "downdifferential",
421 			     &data->ondemand_data.downdifferential);
422 
423 	data->rate = clk_get_rate(data->dmc_clk);
424 
425 	rcu_read_lock();
426 	opp = devfreq_recommended_opp(dev, &data->rate, 0);
427 	if (IS_ERR(opp)) {
428 		rcu_read_unlock();
429 		return PTR_ERR(opp);
430 	}
431 	data->rate = dev_pm_opp_get_freq(opp);
432 	data->volt = dev_pm_opp_get_voltage(opp);
433 	rcu_read_unlock();
434 
435 	rk3399_devfreq_dmc_profile.initial_freq = data->rate;
436 
437 	data->devfreq = devm_devfreq_add_device(dev,
438 					   &rk3399_devfreq_dmc_profile,
439 					   "simple_ondemand",
440 					   &data->ondemand_data);
441 	if (IS_ERR(data->devfreq))
442 		return PTR_ERR(data->devfreq);
443 	devm_devfreq_register_opp_notifier(dev, data->devfreq);
444 
445 	data->dev = dev;
446 	platform_set_drvdata(pdev, data);
447 
448 	return 0;
449 }
450 
451 static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
452 	{ .compatible = "rockchip,rk3399-dmc" },
453 	{ },
454 };
455 MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
456 
457 static struct platform_driver rk3399_dmcfreq_driver = {
458 	.probe	= rk3399_dmcfreq_probe,
459 	.driver = {
460 		.name	= "rk3399-dmc-freq",
461 		.pm	= &rk3399_dmcfreq_pm,
462 		.of_match_table = rk3399dmc_devfreq_of_match,
463 	},
464 };
465 module_platform_driver(rk3399_dmcfreq_driver);
466 
467 MODULE_LICENSE("GPL v2");
468 MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
469 MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
470