2 * OMAP3/OMAP4 Voltage Management Routines
4 * Author: Thara Gopinath <thara@ti.com>
6 * Copyright (C) 2007 Texas Instruments, Inc.
7 * Rajendra Nayak <rnayak@ti.com>
8 * Lesly A M <x0080970@ti.com>
10 * Copyright (C) 2008, 2011 Nokia Corporation
14 * Copyright (C) 2010 Texas Instruments, Inc.
15 * Thara Gopinath <thara@ti.com>
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License version 2 as
19 * published by the Free Software Foundation.
22 #include <linux/delay.h>
24 #include <linux/clk.h>
25 #include <linux/err.h>
26 #include <linux/debugfs.h>
27 #include <linux/slab.h>
29 #include <plat/common.h>
31 #include "prm-regbits-34xx.h"
32 #include "prm-regbits-44xx.h"
35 #include "prminst44xx.h"
39 #include "powerdomain.h"
44 static LIST_HEAD(voltdm_list);
46 #define VOLTAGE_DIR_SIZE 16
47 static struct dentry *voltage_dir;
49 static int __init _config_common_vdd_data(struct voltagedomain *voltdm)
53 u32 sys_clk_speed, timeout_val, waittime;
54 struct omap_vdd_info *vdd = voltdm->vdd;
57 * XXX Clockfw should handle this, or this should be in a
60 if (cpu_is_omap24xx() || cpu_is_omap34xx())
61 sys_ck_name = "sys_ck";
62 else if (cpu_is_omap44xx())
63 sys_ck_name = "sys_clkin_ck";
68 * Sys clk rate is require to calculate vp timeout value and
69 * smpswaittimemin and smpswaittimemax.
71 sys_ck = clk_get(NULL, sys_ck_name);
73 pr_warning("%s: Could not get the sys clk to calculate"
74 "various vdd_%s params\n", __func__, voltdm->name);
77 sys_clk_speed = clk_get_rate(sys_ck);
79 /* Divide to avoid overflow */
80 sys_clk_speed /= 1000;
82 /* Generic voltage parameters */
83 vdd->volt_scale = omap_vp_forceupdate_scale;
84 vdd->vp_enabled = false;
86 vdd->vp_rt_data.vpconfig_erroroffset =
87 (voltdm->pmic->vp_erroroffset <<
88 vdd->vp_data->vp_common->vpconfig_erroroffset_shift);
90 timeout_val = (sys_clk_speed * voltdm->pmic->vp_timeout_us) / 1000;
91 vdd->vp_rt_data.vlimitto_timeout = timeout_val;
92 vdd->vp_rt_data.vlimitto_vddmin = voltdm->pmic->vp_vddmin;
93 vdd->vp_rt_data.vlimitto_vddmax = voltdm->pmic->vp_vddmax;
95 waittime = ((voltdm->pmic->step_size / voltdm->pmic->slew_rate) *
96 sys_clk_speed) / 1000;
97 vdd->vp_rt_data.vstepmin_smpswaittimemin = waittime;
98 vdd->vp_rt_data.vstepmax_smpswaittimemax = waittime;
99 vdd->vp_rt_data.vstepmin_stepmin = voltdm->pmic->vp_vstepmin;
100 vdd->vp_rt_data.vstepmax_stepmax = voltdm->pmic->vp_vstepmax;
105 static int nom_volt_debug_get(void *data, u64 *val)
107 struct voltagedomain *voltdm = (struct voltagedomain *)data;
110 pr_warning("Wrong paramater passed\n");
114 *val = omap_voltage_get_nom_volt(voltdm);
119 DEFINE_SIMPLE_ATTRIBUTE(nom_volt_debug_fops, nom_volt_debug_get, NULL,
121 static void __init vdd_debugfs_init(struct voltagedomain *voltdm)
124 struct omap_vdd_info *vdd = voltdm->vdd;
126 name = kzalloc(VOLTAGE_DIR_SIZE, GFP_KERNEL);
128 pr_warning("%s: Unable to allocate memory for debugfs"
129 " directory name for vdd_%s",
130 __func__, voltdm->name);
133 strcpy(name, "vdd_");
134 strcat(name, voltdm->name);
136 vdd->debug_dir = debugfs_create_dir(name, voltage_dir);
138 if (IS_ERR(vdd->debug_dir)) {
139 pr_warning("%s: Unable to create debugfs directory for"
140 " vdd_%s\n", __func__, voltdm->name);
141 vdd->debug_dir = NULL;
145 (void) debugfs_create_file("curr_nominal_volt", S_IRUGO,
146 vdd->debug_dir, (void *) voltdm,
147 &nom_volt_debug_fops);
150 static int __init omap_vdd_data_configure(struct voltagedomain *voltdm)
155 pr_err("%s: PMIC info requried to configure vdd_%s not"
156 "populated.Hence cannot initialize vdd_%s\n",
157 __func__, voltdm->name, voltdm->name);
161 if (IS_ERR_VALUE(_config_common_vdd_data(voltdm)))
170 /* Public functions */
172 * omap_voltage_get_nom_volt() - Gets the current non-auto-compensated voltage
173 * @voltdm: pointer to the VDD for which current voltage info is needed
175 * API to get the current non-auto-compensated voltage for a VDD.
176 * Returns 0 in case of error else returns the current voltage for the VDD.
178 unsigned long omap_voltage_get_nom_volt(struct voltagedomain *voltdm)
180 struct omap_vdd_info *vdd;
182 if (!voltdm || IS_ERR(voltdm)) {
183 pr_warning("%s: VDD specified does not exist!\n", __func__);
189 return vdd->curr_volt;
193 * omap_voltage_scale_vdd() - API to scale voltage of a particular
195 * @voltdm: pointer to the VDD which is to be scaled.
196 * @target_volt: The target voltage of the voltage domain
198 * This API should be called by the kernel to do the voltage scaling
199 * for a particular voltage domain during dvfs or any other situation.
201 int omap_voltage_scale_vdd(struct voltagedomain *voltdm,
202 unsigned long target_volt)
204 struct omap_vdd_info *vdd;
206 if (!voltdm || IS_ERR(voltdm)) {
207 pr_warning("%s: VDD specified does not exist!\n", __func__);
213 if (!vdd->volt_scale) {
214 pr_err("%s: No voltage scale API registered for vdd_%s\n",
215 __func__, voltdm->name);
219 return vdd->volt_scale(voltdm, target_volt);
223 * omap_voltage_reset() - Resets the voltage of a particular voltage domain
224 * to that of the current OPP.
225 * @voltdm: pointer to the VDD whose voltage is to be reset.
227 * This API finds out the correct voltage the voltage domain is supposed
228 * to be at and resets the voltage to that level. Should be used especially
229 * while disabling any voltage compensation modules.
231 void omap_voltage_reset(struct voltagedomain *voltdm)
233 unsigned long target_uvdc;
235 if (!voltdm || IS_ERR(voltdm)) {
236 pr_warning("%s: VDD specified does not exist!\n", __func__);
240 target_uvdc = omap_voltage_get_nom_volt(voltdm);
242 pr_err("%s: unable to find current voltage for vdd_%s\n",
243 __func__, voltdm->name);
247 omap_voltage_scale_vdd(voltdm, target_uvdc);
251 * omap_voltage_get_volttable() - API to get the voltage table associated with a
252 * particular voltage domain.
253 * @voltdm: pointer to the VDD for which the voltage table is required
254 * @volt_data: the voltage table for the particular vdd which is to be
255 * populated by this API
257 * This API populates the voltage table associated with a VDD into the
258 * passed parameter pointer. Returns the count of distinct voltages
259 * supported by this vdd.
262 void omap_voltage_get_volttable(struct voltagedomain *voltdm,
263 struct omap_volt_data **volt_data)
265 struct omap_vdd_info *vdd;
267 if (!voltdm || IS_ERR(voltdm)) {
268 pr_warning("%s: VDD specified does not exist!\n", __func__);
274 *volt_data = vdd->volt_data;
278 * omap_voltage_get_voltdata() - API to get the voltage table entry for a
280 * @voltdm: pointer to the VDD whose voltage table has to be searched
281 * @volt: the voltage to be searched in the voltage table
283 * This API searches through the voltage table for the required voltage
284 * domain and tries to find a matching entry for the passed voltage volt.
285 * If a matching entry is found volt_data is populated with that entry.
286 * This API searches only through the non-compensated voltages int the
288 * Returns pointer to the voltage table entry corresponding to volt on
289 * success. Returns -ENODATA if no voltage table exisits for the passed voltage
290 * domain or if there is no matching entry.
292 struct omap_volt_data *omap_voltage_get_voltdata(struct voltagedomain *voltdm,
295 struct omap_vdd_info *vdd;
298 if (!voltdm || IS_ERR(voltdm)) {
299 pr_warning("%s: VDD specified does not exist!\n", __func__);
300 return ERR_PTR(-EINVAL);
305 if (!vdd->volt_data) {
306 pr_warning("%s: voltage table does not exist for vdd_%s\n",
307 __func__, voltdm->name);
308 return ERR_PTR(-ENODATA);
311 for (i = 0; vdd->volt_data[i].volt_nominal != 0; i++) {
312 if (vdd->volt_data[i].volt_nominal == volt)
313 return &vdd->volt_data[i];
316 pr_notice("%s: Unable to match the current voltage with the voltage"
317 "table for vdd_%s\n", __func__, voltdm->name);
319 return ERR_PTR(-ENODATA);
323 * omap_voltage_register_pmic() - API to register PMIC specific data
324 * @voltdm: pointer to the VDD for which the PMIC specific data is
326 * @pmic: the structure containing pmic info
328 * This API is to be called by the SOC/PMIC file to specify the
329 * pmic specific info as present in omap_voltdm_pmic structure.
331 int omap_voltage_register_pmic(struct voltagedomain *voltdm,
332 struct omap_voltdm_pmic *pmic)
334 if (!voltdm || IS_ERR(voltdm)) {
335 pr_warning("%s: VDD specified does not exist!\n", __func__);
345 * omap_voltage_get_dbgdir() - API to get pointer to the debugfs directory
346 * corresponding to a voltage domain.
348 * @voltdm: pointer to the VDD whose debug directory is required.
350 * This API returns pointer to the debugfs directory corresponding
351 * to the voltage domain. Should be used by drivers requiring to
352 * add any debug entry for a particular voltage domain. Returns NULL
355 struct dentry *omap_voltage_get_dbgdir(struct voltagedomain *voltdm)
357 struct omap_vdd_info *vdd;
359 if (!voltdm || IS_ERR(voltdm)) {
360 pr_warning("%s: VDD specified does not exist!\n", __func__);
366 return vdd->debug_dir;
370 * omap_change_voltscale_method() - API to change the voltage scaling method.
371 * @voltdm: pointer to the VDD whose voltage scaling method
373 * @voltscale_method: the method to be used for voltage scaling.
375 * This API can be used by the board files to change the method of voltage
376 * scaling between vpforceupdate and vcbypass. The parameter values are
377 * defined in voltage.h
379 void omap_change_voltscale_method(struct voltagedomain *voltdm,
380 int voltscale_method)
382 struct omap_vdd_info *vdd;
384 if (!voltdm || IS_ERR(voltdm)) {
385 pr_warning("%s: VDD specified does not exist!\n", __func__);
391 switch (voltscale_method) {
392 case VOLTSCALE_VPFORCEUPDATE:
393 vdd->volt_scale = omap_vp_forceupdate_scale;
395 case VOLTSCALE_VCBYPASS:
396 vdd->volt_scale = omap_vc_bypass_scale;
399 pr_warning("%s: Trying to change the method of voltage scaling"
400 "to an unsupported one!\n", __func__);
405 * omap_voltage_late_init() - Init the various voltage parameters
407 * This API is to be called in the later stages of the
408 * system boot to init the voltage controller and
409 * voltage processors.
411 int __init omap_voltage_late_init(void)
413 struct voltagedomain *voltdm;
415 if (list_empty(&voltdm_list)) {
416 pr_err("%s: Voltage driver support not added\n",
421 voltage_dir = debugfs_create_dir("voltage", NULL);
422 if (IS_ERR(voltage_dir))
423 pr_err("%s: Unable to create voltage debugfs main dir\n",
425 list_for_each_entry(voltdm, &voltdm_list, node) {
426 if (!voltdm->scalable)
430 voltdm->vdd->volt_scale = omap_vc_bypass_scale;
431 omap_vc_init_channel(voltdm);
435 if (omap_vdd_data_configure(voltdm))
437 vdd_debugfs_init(voltdm);
438 omap_vp_init(voltdm);
445 static struct voltagedomain *_voltdm_lookup(const char *name)
447 struct voltagedomain *voltdm, *temp_voltdm;
451 list_for_each_entry(temp_voltdm, &voltdm_list, node) {
452 if (!strcmp(name, temp_voltdm->name)) {
453 voltdm = temp_voltdm;
462 * voltdm_add_pwrdm - add a powerdomain to a voltagedomain
463 * @voltdm: struct voltagedomain * to add the powerdomain to
464 * @pwrdm: struct powerdomain * to associate with a voltagedomain
466 * Associate the powerdomain @pwrdm with a voltagedomain @voltdm. This
467 * enables the use of voltdm_for_each_pwrdm(). Returns -EINVAL if
468 * presented with invalid pointers; -ENOMEM if memory could not be allocated;
471 int voltdm_add_pwrdm(struct voltagedomain *voltdm, struct powerdomain *pwrdm)
473 if (!voltdm || !pwrdm)
476 pr_debug("voltagedomain: associating powerdomain %s with voltagedomain "
477 "%s\n", pwrdm->name, voltdm->name);
479 list_add(&pwrdm->voltdm_node, &voltdm->pwrdm_list);
485 * voltdm_for_each_pwrdm - call function for each pwrdm in a voltdm
486 * @voltdm: struct voltagedomain * to iterate over
487 * @fn: callback function *
489 * Call the supplied function @fn for each powerdomain in the
490 * voltagedomain @voltdm. Returns -EINVAL if presented with invalid
491 * pointers; or passes along the last return value of the callback
492 * function, which should be 0 for success or anything else to
495 int voltdm_for_each_pwrdm(struct voltagedomain *voltdm,
496 int (*fn)(struct voltagedomain *voltdm,
497 struct powerdomain *pwrdm))
499 struct powerdomain *pwrdm;
505 list_for_each_entry(pwrdm, &voltdm->pwrdm_list, voltdm_node)
506 ret = (*fn)(voltdm, pwrdm);
512 * voltdm_for_each - call function on each registered voltagedomain
513 * @fn: callback function *
515 * Call the supplied function @fn for each registered voltagedomain.
516 * The callback function @fn can return anything but 0 to bail out
517 * early from the iterator. Returns the last return value of the
518 * callback function, which should be 0 for success or anything else
519 * to indicate failure; or -EINVAL if the function pointer is null.
521 int voltdm_for_each(int (*fn)(struct voltagedomain *voltdm, void *user),
524 struct voltagedomain *temp_voltdm;
530 list_for_each_entry(temp_voltdm, &voltdm_list, node) {
531 ret = (*fn)(temp_voltdm, user);
539 static int _voltdm_register(struct voltagedomain *voltdm)
541 if (!voltdm || !voltdm->name)
544 INIT_LIST_HEAD(&voltdm->pwrdm_list);
545 list_add(&voltdm->node, &voltdm_list);
547 pr_debug("voltagedomain: registered %s\n", voltdm->name);
553 * voltdm_lookup - look up a voltagedomain by name, return a pointer
554 * @name: name of voltagedomain
556 * Find a registered voltagedomain by its name @name. Returns a pointer
557 * to the struct voltagedomain if found, or NULL otherwise.
559 struct voltagedomain *voltdm_lookup(const char *name)
561 struct voltagedomain *voltdm ;
566 voltdm = _voltdm_lookup(name);
572 * voltdm_init - set up the voltagedomain layer
573 * @voltdm_list: array of struct voltagedomain pointers to register
575 * Loop through the array of voltagedomains @voltdm_list, registering all
576 * that are available on the current CPU. If voltdm_list is supplied
577 * and not null, all of the referenced voltagedomains will be
578 * registered. No return value.
580 void voltdm_init(struct voltagedomain **voltdms)
582 struct voltagedomain **v;
585 for (v = voltdms; *v; v++)
586 _voltdm_register(*v);