drivers/devfreq/rk3399_dmc.c

   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");