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1/*
2 * OMAP Voltage Controller (VC) interface
3 *
4 * Copyright (C) 2011 Texas Instruments, Inc.
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 */
10#include <linux/kernel.h>
11#include <linux/delay.h>
12#include <linux/init.h>
13#include <linux/bug.h>
14#include <linux/io.h>
15
16#include <asm/div64.h>
17
18#include "iomap.h"
19#include "soc.h"
20#include "voltage.h"
21#include "vc.h"
22#include "prm-regbits-34xx.h"
23#include "prm-regbits-44xx.h"
24#include "prm44xx.h"
25#include "pm.h"
26#include "scrm44xx.h"
27#include "control.h"
28
29/**
30 * struct omap_vc_channel_cfg - describe the cfg_channel bitfield
31 * @sa: bit for slave address
32 * @rav: bit for voltage configuration register
33 * @rac: bit for command configuration register
34 * @racen: enable bit for RAC
35 * @cmd: bit for command value set selection
36 *
37 * Channel configuration bits, common for OMAP3+
38 * OMAP3 register: PRM_VC_CH_CONF
39 * OMAP4 register: PRM_VC_CFG_CHANNEL
40 * OMAP5 register: PRM_VC_SMPS_<voltdm>_CONFIG
41 */
42struct omap_vc_channel_cfg {
43 u8 sa;
44 u8 rav;
45 u8 rac;
46 u8 racen;
47 u8 cmd;
48};
49
50static struct omap_vc_channel_cfg vc_default_channel_cfg = {
51 .sa = BIT(0),
52 .rav = BIT(1),
53 .rac = BIT(2),
54 .racen = BIT(3),
55 .cmd = BIT(4),
56};
57
58/*
59 * On OMAP3+, all VC channels have the above default bitfield
60 * configuration, except the OMAP4 MPU channel. This appears
61 * to be a freak accident as every other VC channel has the
62 * default configuration, thus creating a mutant channel config.
63 */
64static struct omap_vc_channel_cfg vc_mutant_channel_cfg = {
65 .sa = BIT(0),
66 .rav = BIT(2),
67 .rac = BIT(3),
68 .racen = BIT(4),
69 .cmd = BIT(1),
70};
71
72static struct omap_vc_channel_cfg *vc_cfg_bits;
73
74/* Default I2C trace length on pcb, 6.3cm. Used for capacitance calculations. */
75static u32 sr_i2c_pcb_length = 63;
76#define CFG_CHANNEL_MASK 0x1f
77
78/**
79 * omap_vc_config_channel - configure VC channel to PMIC mappings
80 * @voltdm: pointer to voltagdomain defining the desired VC channel
81 *
82 * Configures the VC channel to PMIC mappings for the following
83 * PMIC settings
84 * - i2c slave address (SA)
85 * - voltage configuration address (RAV)
86 * - command configuration address (RAC) and enable bit (RACEN)
87 * - command values for ON, ONLP, RET and OFF (CMD)
88 *
89 * This function currently only allows flexible configuration of the
90 * non-default channel. Starting with OMAP4, there are more than 2
91 * channels, with one defined as the default (on OMAP4, it's MPU.)
92 * Only the non-default channel can be configured.
93 */
94static int omap_vc_config_channel(struct voltagedomain *voltdm)
95{
96 struct omap_vc_channel *vc = voltdm->vc;
97
98 /*
99 * For default channel, the only configurable bit is RACEN.
100 * All others must stay at zero (see function comment above.)
101 */
102 if (vc->flags & OMAP_VC_CHANNEL_DEFAULT)
103 vc->cfg_channel &= vc_cfg_bits->racen;
104
105 voltdm->rmw(CFG_CHANNEL_MASK << vc->cfg_channel_sa_shift,
106 vc->cfg_channel << vc->cfg_channel_sa_shift,
107 vc->cfg_channel_reg);
108
109 return 0;
110}
111
112/* Voltage scale and accessory APIs */
113int omap_vc_pre_scale(struct voltagedomain *voltdm,
114 unsigned long target_volt,
115 u8 *target_vsel, u8 *current_vsel)
116{
117 struct omap_vc_channel *vc = voltdm->vc;
118 u32 vc_cmdval;
119
120 /* Check if sufficient pmic info is available for this vdd */
121 if (!voltdm->pmic) {
122 pr_err("%s: Insufficient pmic info to scale the vdd_%s\n",
123 __func__, voltdm->name);
124 return -EINVAL;
125 }
126
127 if (!voltdm->pmic->uv_to_vsel) {
128 pr_err("%s: PMIC function to convert voltage in uV to vsel not registered. Hence unable to scale voltage for vdd_%s\n",
129 __func__, voltdm->name);
130 return -ENODATA;
131 }
132
133 if (!voltdm->read || !voltdm->write) {
134 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
135 __func__, voltdm->name);
136 return -EINVAL;
137 }
138
139 *target_vsel = voltdm->pmic->uv_to_vsel(target_volt);
140 *current_vsel = voltdm->pmic->uv_to_vsel(voltdm->nominal_volt);
141
142 /* Setting the ON voltage to the new target voltage */
143 vc_cmdval = voltdm->read(vc->cmdval_reg);
144 vc_cmdval &= ~vc->common->cmd_on_mask;
145 vc_cmdval |= (*target_vsel << vc->common->cmd_on_shift);
146 voltdm->write(vc_cmdval, vc->cmdval_reg);
147
148 voltdm->vc_param->on = target_volt;
149
150 omap_vp_update_errorgain(voltdm, target_volt);
151
152 return 0;
153}
154
155void omap_vc_post_scale(struct voltagedomain *voltdm,
156 unsigned long target_volt,
157 u8 target_vsel, u8 current_vsel)
158{
159 u32 smps_steps = 0, smps_delay = 0;
160
161 smps_steps = abs(target_vsel - current_vsel);
162 /* SMPS slew rate / step size. 2us added as buffer. */
163 smps_delay = ((smps_steps * voltdm->pmic->step_size) /
164 voltdm->pmic->slew_rate) + 2;
165 udelay(smps_delay);
166}
167
168/* vc_bypass_scale - VC bypass method of voltage scaling */
169int omap_vc_bypass_scale(struct voltagedomain *voltdm,
170 unsigned long target_volt)
171{
172 struct omap_vc_channel *vc = voltdm->vc;
173 u32 loop_cnt = 0, retries_cnt = 0;
174 u32 vc_valid, vc_bypass_val_reg, vc_bypass_value;
175 u8 target_vsel, current_vsel;
176 int ret;
177
178 ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, ¤t_vsel);
179 if (ret)
180 return ret;
181
182 vc_valid = vc->common->valid;
183 vc_bypass_val_reg = vc->common->bypass_val_reg;
184 vc_bypass_value = (target_vsel << vc->common->data_shift) |
185 (vc->volt_reg_addr << vc->common->regaddr_shift) |
186 (vc->i2c_slave_addr << vc->common->slaveaddr_shift);
187
188 voltdm->write(vc_bypass_value, vc_bypass_val_reg);
189 voltdm->write(vc_bypass_value | vc_valid, vc_bypass_val_reg);
190
191 vc_bypass_value = voltdm->read(vc_bypass_val_reg);
192 /*
193 * Loop till the bypass command is acknowledged from the SMPS.
194 * NOTE: This is legacy code. The loop count and retry count needs
195 * to be revisited.
196 */
197 while (!(vc_bypass_value & vc_valid)) {
198 loop_cnt++;
199
200 if (retries_cnt > 10) {
201 pr_warn("%s: Retry count exceeded\n", __func__);
202 return -ETIMEDOUT;
203 }
204
205 if (loop_cnt > 50) {
206 retries_cnt++;
207 loop_cnt = 0;
208 udelay(10);
209 }
210 vc_bypass_value = voltdm->read(vc_bypass_val_reg);
211 }
212
213 omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
214 return 0;
215}
216
217/* Convert microsecond value to number of 32kHz clock cycles */
218static inline u32 omap_usec_to_32k(u32 usec)
219{
220 return DIV_ROUND_UP_ULL(32768ULL * (u64)usec, 1000000ULL);
221}
222
223struct omap3_vc_timings {
224 u32 voltsetup1;
225 u32 voltsetup2;
226};
227
228struct omap3_vc {
229 struct voltagedomain *vd;
230 u32 voltctrl;
231 u32 voltsetup1;
232 u32 voltsetup2;
233 struct omap3_vc_timings timings[2];
234};
235static struct omap3_vc vc;
236
237void omap3_vc_set_pmic_signaling(int core_next_state)
238{
239 struct voltagedomain *vd = vc.vd;
240 struct omap3_vc_timings *c = vc.timings;
241 u32 voltctrl, voltsetup1, voltsetup2;
242
243 voltctrl = vc.voltctrl;
244 voltsetup1 = vc.voltsetup1;
245 voltsetup2 = vc.voltsetup2;
246
247 switch (core_next_state) {
248 case PWRDM_POWER_OFF:
249 voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_RET |
250 OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP);
251 voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_OFF;
252 if (voltctrl & OMAP3430_PRM_VOLTCTRL_SEL_OFF)
253 voltsetup2 = c->voltsetup2;
254 else
255 voltsetup1 = c->voltsetup1;
256 break;
257 case PWRDM_POWER_RET:
258 default:
259 c++;
260 voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_OFF |
261 OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP);
262 voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_RET;
263 voltsetup1 = c->voltsetup1;
264 break;
265 }
266
267 if (voltctrl != vc.voltctrl) {
268 vd->write(voltctrl, OMAP3_PRM_VOLTCTRL_OFFSET);
269 vc.voltctrl = voltctrl;
270 }
271 if (voltsetup1 != vc.voltsetup1) {
272 vd->write(c->voltsetup1,
273 OMAP3_PRM_VOLTSETUP1_OFFSET);
274 vc.voltsetup1 = voltsetup1;
275 }
276 if (voltsetup2 != vc.voltsetup2) {
277 vd->write(c->voltsetup2,
278 OMAP3_PRM_VOLTSETUP2_OFFSET);
279 vc.voltsetup2 = voltsetup2;
280 }
281}
282
283/*
284 * Configure signal polarity for sys_clkreq and sys_off_mode pins
285 * as the default values are wrong and can cause the system to hang
286 * if any twl4030 scripts are loaded.
287 */
288static void __init omap3_vc_init_pmic_signaling(struct voltagedomain *voltdm)
289{
290 u32 val;
291
292 if (vc.vd)
293 return;
294
295 vc.vd = voltdm;
296
297 val = voltdm->read(OMAP3_PRM_POLCTRL_OFFSET);
298 if (!(val & OMAP3430_PRM_POLCTRL_CLKREQ_POL) ||
299 (val & OMAP3430_PRM_POLCTRL_OFFMODE_POL)) {
300 val |= OMAP3430_PRM_POLCTRL_CLKREQ_POL;
301 val &= ~OMAP3430_PRM_POLCTRL_OFFMODE_POL;
302 pr_debug("PM: fixing sys_clkreq and sys_off_mode polarity to 0x%x\n",
303 val);
304 voltdm->write(val, OMAP3_PRM_POLCTRL_OFFSET);
305 }
306
307 /*
308 * By default let's use I2C4 signaling for retention idle
309 * and sys_off_mode pin signaling for off idle. This way we
310 * have sys_clk_req pin go down for retention and both
311 * sys_clk_req and sys_off_mode pins will go down for off
312 * idle. And we can also scale voltages to zero for off-idle.
313 * Note that no actual voltage scaling during off-idle will
314 * happen unless the board specific twl4030 PMIC scripts are
315 * loaded. See also omap_vc_i2c_init for comments regarding
316 * erratum i531.
317 */
318 val = voltdm->read(OMAP3_PRM_VOLTCTRL_OFFSET);
319 if (!(val & OMAP3430_PRM_VOLTCTRL_SEL_OFF)) {
320 val |= OMAP3430_PRM_VOLTCTRL_SEL_OFF;
321 pr_debug("PM: setting voltctrl sys_off_mode signaling to 0x%x\n",
322 val);
323 voltdm->write(val, OMAP3_PRM_VOLTCTRL_OFFSET);
324 }
325 vc.voltctrl = val;
326
327 omap3_vc_set_pmic_signaling(PWRDM_POWER_ON);
328}
329
330static void omap3_init_voltsetup1(struct voltagedomain *voltdm,
331 struct omap3_vc_timings *c, u32 idle)
332{
333 unsigned long val;
334
335 val = (voltdm->vc_param->on - idle) / voltdm->pmic->slew_rate;
336 val *= voltdm->sys_clk.rate / 8 / 1000000 + 1;
337 val <<= __ffs(voltdm->vfsm->voltsetup_mask);
338 c->voltsetup1 &= ~voltdm->vfsm->voltsetup_mask;
339 c->voltsetup1 |= val;
340}
341
342/**
343 * omap3_set_i2c_timings - sets i2c sleep timings for a channel
344 * @voltdm: channel to configure
345 * @off_mode: select whether retention or off mode values used
346 *
347 * Calculates and sets up voltage controller to use I2C based
348 * voltage scaling for sleep modes. This can be used for either off mode
349 * or retention. Off mode has additionally an option to use sys_off_mode
350 * pad, which uses a global signal to program the whole power IC to
351 * off-mode.
352 *
353 * Note that pmic is not controlling the voltage scaling during
354 * retention signaled over I2C4, so we can keep voltsetup2 as 0.
355 * And the oscillator is not shut off over I2C4, so no need to
356 * set clksetup.
357 */
358static void omap3_set_i2c_timings(struct voltagedomain *voltdm)
359{
360 struct omap3_vc_timings *c = vc.timings;
361
362 /* Configure PRWDM_POWER_OFF over I2C4 */
363 omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->off);
364 c++;
365 /* Configure PRWDM_POWER_RET over I2C4 */
366 omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->ret);
367}
368
369/**
370 * omap3_set_off_timings - sets off-mode timings for a channel
371 * @voltdm: channel to configure
372 *
373 * Calculates and sets up off-mode timings for a channel. Off-mode
374 * can use either I2C based voltage scaling, or alternatively
375 * sys_off_mode pad can be used to send a global command to power IC.n,
376 * sys_off_mode has the additional benefit that voltages can be
377 * scaled to zero volt level with TWL4030 / TWL5030, I2C can only
378 * scale to 600mV.
379 *
380 * Note that omap is not controlling the voltage scaling during
381 * off idle signaled by sys_off_mode, so we can keep voltsetup1
382 * as 0.
383 */
384static void omap3_set_off_timings(struct voltagedomain *voltdm)
385{
386 struct omap3_vc_timings *c = vc.timings;
387 u32 tstart, tshut, clksetup, voltoffset;
388
389 if (c->voltsetup2)
390 return;
391
392 omap_pm_get_oscillator(&tstart, &tshut);
393 if (tstart == ULONG_MAX) {
394 pr_debug("PM: oscillator start-up time not initialized, using 10ms\n");
395 clksetup = omap_usec_to_32k(10000);
396 } else {
397 clksetup = omap_usec_to_32k(tstart);
398 }
399
400 /*
401 * For twl4030 errata 27, we need to allow minimum ~488.32 us wait to
402 * switch from HFCLKIN to internal oscillator. That means timings
403 * have voltoffset fixed to 0xa in rounded up 32 KiHz cycles. And
404 * that means we can calculate the value based on the oscillator
405 * start-up time since voltoffset2 = clksetup - voltoffset.
406 */
407 voltoffset = omap_usec_to_32k(488);
408 c->voltsetup2 = clksetup - voltoffset;
409 voltdm->write(clksetup, OMAP3_PRM_CLKSETUP_OFFSET);
410 voltdm->write(voltoffset, OMAP3_PRM_VOLTOFFSET_OFFSET);
411}
412
413static void __init omap3_vc_init_channel(struct voltagedomain *voltdm)
414{
415 omap3_vc_init_pmic_signaling(voltdm);
416 omap3_set_off_timings(voltdm);
417 omap3_set_i2c_timings(voltdm);
418}
419
420/**
421 * omap4_calc_volt_ramp - calculates voltage ramping delays on omap4
422 * @voltdm: channel to calculate values for
423 * @voltage_diff: voltage difference in microvolts
424 *
425 * Calculates voltage ramp prescaler + counter values for a voltage
426 * difference on omap4. Returns a field value suitable for writing to
427 * VOLTSETUP register for a channel in following format:
428 * bits[8:9] prescaler ... bits[0:5] counter. See OMAP4 TRM for reference.
429 */
430static u32 omap4_calc_volt_ramp(struct voltagedomain *voltdm, u32 voltage_diff)
431{
432 u32 prescaler;
433 u32 cycles;
434 u32 time;
435
436 time = voltage_diff / voltdm->pmic->slew_rate;
437
438 cycles = voltdm->sys_clk.rate / 1000 * time / 1000;
439
440 cycles /= 64;
441 prescaler = 0;
442
443 /* shift to next prescaler until no overflow */
444
445 /* scale for div 256 = 64 * 4 */
446 if (cycles > 63) {
447 cycles /= 4;
448 prescaler++;
449 }
450
451 /* scale for div 512 = 256 * 2 */
452 if (cycles > 63) {
453 cycles /= 2;
454 prescaler++;
455 }
456
457 /* scale for div 2048 = 512 * 4 */
458 if (cycles > 63) {
459 cycles /= 4;
460 prescaler++;
461 }
462
463 /* check for overflow => invalid ramp time */
464 if (cycles > 63) {
465 pr_warn("%s: invalid setuptime for vdd_%s\n", __func__,
466 voltdm->name);
467 return 0;
468 }
469
470 cycles++;
471
472 return (prescaler << OMAP4430_RAMP_UP_PRESCAL_SHIFT) |
473 (cycles << OMAP4430_RAMP_UP_COUNT_SHIFT);
474}
475
476/**
477 * omap4_usec_to_val_scrm - convert microsecond value to SCRM module bitfield
478 * @usec: microseconds
479 * @shift: number of bits to shift left
480 * @mask: bitfield mask
481 *
482 * Converts microsecond value to OMAP4 SCRM bitfield. Bitfield is
483 * shifted to requested position, and checked agains the mask value.
484 * If larger, forced to the max value of the field (i.e. the mask itself.)
485 * Returns the SCRM bitfield value.
486 */
487static u32 omap4_usec_to_val_scrm(u32 usec, int shift, u32 mask)
488{
489 u32 val;
490
491 val = omap_usec_to_32k(usec) << shift;
492
493 /* Check for overflow, if yes, force to max value */
494 if (val > mask)
495 val = mask;
496
497 return val;
498}
499
500/**
501 * omap4_set_timings - set voltage ramp timings for a channel
502 * @voltdm: channel to configure
503 * @off_mode: whether off-mode values are used
504 *
505 * Calculates and sets the voltage ramp up / down values for a channel.
506 */
507static void omap4_set_timings(struct voltagedomain *voltdm, bool off_mode)
508{
509 u32 val;
510 u32 ramp;
511 int offset;
512 u32 tstart, tshut;
513
514 if (off_mode) {
515 ramp = omap4_calc_volt_ramp(voltdm,
516 voltdm->vc_param->on - voltdm->vc_param->off);
517 offset = voltdm->vfsm->voltsetup_off_reg;
518 } else {
519 ramp = omap4_calc_volt_ramp(voltdm,
520 voltdm->vc_param->on - voltdm->vc_param->ret);
521 offset = voltdm->vfsm->voltsetup_reg;
522 }
523
524 if (!ramp)
525 return;
526
527 val = voltdm->read(offset);
528
529 val |= ramp << OMAP4430_RAMP_DOWN_COUNT_SHIFT;
530
531 val |= ramp << OMAP4430_RAMP_UP_COUNT_SHIFT;
532
533 voltdm->write(val, offset);
534
535 omap_pm_get_oscillator(&tstart, &tshut);
536
537 val = omap4_usec_to_val_scrm(tstart, OMAP4_SETUPTIME_SHIFT,
538 OMAP4_SETUPTIME_MASK);
539 val |= omap4_usec_to_val_scrm(tshut, OMAP4_DOWNTIME_SHIFT,
540 OMAP4_DOWNTIME_MASK);
541
542 writel_relaxed(val, OMAP4_SCRM_CLKSETUPTIME);
543}
544
545/* OMAP4 specific voltage init functions */
546static void __init omap4_vc_init_channel(struct voltagedomain *voltdm)
547{
548 omap4_set_timings(voltdm, true);
549 omap4_set_timings(voltdm, false);
550}
551
552struct i2c_init_data {
553 u8 loadbits;
554 u8 load;
555 u8 hsscll_38_4;
556 u8 hsscll_26;
557 u8 hsscll_19_2;
558 u8 hsscll_16_8;
559 u8 hsscll_12;
560};
561
562static const struct i2c_init_data omap4_i2c_timing_data[] __initconst = {
563 {
564 .load = 50,
565 .loadbits = 0x3,
566 .hsscll_38_4 = 13,
567 .hsscll_26 = 11,
568 .hsscll_19_2 = 9,
569 .hsscll_16_8 = 9,
570 .hsscll_12 = 8,
571 },
572 {
573 .load = 25,
574 .loadbits = 0x2,
575 .hsscll_38_4 = 13,
576 .hsscll_26 = 11,
577 .hsscll_19_2 = 9,
578 .hsscll_16_8 = 9,
579 .hsscll_12 = 8,
580 },
581 {
582 .load = 12,
583 .loadbits = 0x1,
584 .hsscll_38_4 = 11,
585 .hsscll_26 = 10,
586 .hsscll_19_2 = 9,
587 .hsscll_16_8 = 9,
588 .hsscll_12 = 8,
589 },
590 {
591 .load = 0,
592 .loadbits = 0x0,
593 .hsscll_38_4 = 12,
594 .hsscll_26 = 10,
595 .hsscll_19_2 = 9,
596 .hsscll_16_8 = 8,
597 .hsscll_12 = 8,
598 },
599};
600
601/**
602 * omap4_vc_i2c_timing_init - sets up board I2C timing parameters
603 * @voltdm: voltagedomain pointer to get data from
604 *
605 * Use PMIC + board supplied settings for calculating the total I2C
606 * channel capacitance and set the timing parameters based on this.
607 * Pre-calculated values are provided in data tables, as it is not
608 * too straightforward to calculate these runtime.
609 */
610static void __init omap4_vc_i2c_timing_init(struct voltagedomain *voltdm)
611{
612 u32 capacitance;
613 u32 val;
614 u16 hsscll;
615 const struct i2c_init_data *i2c_data;
616
617 if (!voltdm->pmic->i2c_high_speed) {
618 pr_warn("%s: only high speed supported!\n", __func__);
619 return;
620 }
621
622 /* PCB trace capacitance, 0.125pF / mm => mm / 8 */
623 capacitance = DIV_ROUND_UP(sr_i2c_pcb_length, 8);
624
625 /* OMAP pad capacitance */
626 capacitance += 4;
627
628 /* PMIC pad capacitance */
629 capacitance += voltdm->pmic->i2c_pad_load;
630
631 /* Search for capacitance match in the table */
632 i2c_data = omap4_i2c_timing_data;
633
634 while (i2c_data->load > capacitance)
635 i2c_data++;
636
637 /* Select proper values based on sysclk frequency */
638 switch (voltdm->sys_clk.rate) {
639 case 38400000:
640 hsscll = i2c_data->hsscll_38_4;
641 break;
642 case 26000000:
643 hsscll = i2c_data->hsscll_26;
644 break;
645 case 19200000:
646 hsscll = i2c_data->hsscll_19_2;
647 break;
648 case 16800000:
649 hsscll = i2c_data->hsscll_16_8;
650 break;
651 case 12000000:
652 hsscll = i2c_data->hsscll_12;
653 break;
654 default:
655 pr_warn("%s: unsupported sysclk rate: %d!\n", __func__,
656 voltdm->sys_clk.rate);
657 return;
658 }
659
660 /* Loadbits define pull setup for the I2C channels */
661 val = i2c_data->loadbits << 25 | i2c_data->loadbits << 29;
662
663 /* Write to SYSCTRL_PADCONF_WKUP_CTRL_I2C_2 to setup I2C pull */
664 writel_relaxed(val, OMAP2_L4_IO_ADDRESS(OMAP4_CTRL_MODULE_PAD_WKUP +
665 OMAP4_CTRL_MODULE_PAD_WKUP_CONTROL_I2C_2));
666
667 /* HSSCLH can always be zero */
668 val = hsscll << OMAP4430_HSSCLL_SHIFT;
669 val |= (0x28 << OMAP4430_SCLL_SHIFT | 0x2c << OMAP4430_SCLH_SHIFT);
670
671 /* Write setup times to I2C config register */
672 voltdm->write(val, OMAP4_PRM_VC_CFG_I2C_CLK_OFFSET);
673}
674
675
676
677/**
678 * omap_vc_i2c_init - initialize I2C interface to PMIC
679 * @voltdm: voltage domain containing VC data
680 *
681 * Use PMIC supplied settings for I2C high-speed mode and
682 * master code (if set) and program the VC I2C configuration
683 * register.
684 *
685 * The VC I2C configuration is common to all VC channels,
686 * so this function only configures I2C for the first VC
687 * channel registers. All other VC channels will use the
688 * same configuration.
689 */
690static void __init omap_vc_i2c_init(struct voltagedomain *voltdm)
691{
692 struct omap_vc_channel *vc = voltdm->vc;
693 static bool initialized;
694 static bool i2c_high_speed;
695 u8 mcode;
696
697 if (initialized) {
698 if (voltdm->pmic->i2c_high_speed != i2c_high_speed)
699 pr_warn("%s: I2C config for vdd_%s does not match other channels (%u).\n",
700 __func__, voltdm->name, i2c_high_speed);
701 return;
702 }
703
704 /*
705 * Note that for omap3 OMAP3430_SREN_MASK clears SREN to work around
706 * erratum i531 "Extra Power Consumed When Repeated Start Operation
707 * Mode Is Enabled on I2C Interface Dedicated for Smart Reflex (I2C4)".
708 * Otherwise I2C4 eventually leads into about 23mW extra power being
709 * consumed even during off idle using VMODE.
710 */
711 i2c_high_speed = voltdm->pmic->i2c_high_speed;
712 if (i2c_high_speed)
713 voltdm->rmw(vc->common->i2c_cfg_clear_mask,
714 vc->common->i2c_cfg_hsen_mask,
715 vc->common->i2c_cfg_reg);
716
717 mcode = voltdm->pmic->i2c_mcode;
718 if (mcode)
719 voltdm->rmw(vc->common->i2c_mcode_mask,
720 mcode << __ffs(vc->common->i2c_mcode_mask),
721 vc->common->i2c_cfg_reg);
722
723 if (cpu_is_omap44xx())
724 omap4_vc_i2c_timing_init(voltdm);
725
726 initialized = true;
727}
728
729/**
730 * omap_vc_calc_vsel - calculate vsel value for a channel
731 * @voltdm: channel to calculate value for
732 * @uvolt: microvolt value to convert to vsel
733 *
734 * Converts a microvolt value to vsel value for the used PMIC.
735 * This checks whether the microvolt value is out of bounds, and
736 * adjusts the value accordingly. If unsupported value detected,
737 * warning is thrown.
738 */
739static u8 omap_vc_calc_vsel(struct voltagedomain *voltdm, u32 uvolt)
740{
741 if (voltdm->pmic->vddmin > uvolt)
742 uvolt = voltdm->pmic->vddmin;
743 if (voltdm->pmic->vddmax < uvolt) {
744 WARN(1, "%s: voltage not supported by pmic: %u vs max %u\n",
745 __func__, uvolt, voltdm->pmic->vddmax);
746 /* Lets try maximum value anyway */
747 uvolt = voltdm->pmic->vddmax;
748 }
749
750 return voltdm->pmic->uv_to_vsel(uvolt);
751}
752
753#ifdef CONFIG_PM
754/**
755 * omap_pm_setup_sr_i2c_pcb_length - set length of SR I2C traces on PCB
756 * @mm: length of the PCB trace in millimetres
757 *
758 * Sets the PCB trace length for the I2C channel. By default uses 63mm.
759 * This is needed for properly calculating the capacitance value for
760 * the PCB trace, and for setting the SR I2C channel timing parameters.
761 */
762void __init omap_pm_setup_sr_i2c_pcb_length(u32 mm)
763{
764 sr_i2c_pcb_length = mm;
765}
766#endif
767
768void __init omap_vc_init_channel(struct voltagedomain *voltdm)
769{
770 struct omap_vc_channel *vc = voltdm->vc;
771 u8 on_vsel, onlp_vsel, ret_vsel, off_vsel;
772 u32 val;
773
774 if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
775 pr_err("%s: No PMIC info for vdd_%s\n", __func__, voltdm->name);
776 return;
777 }
778
779 if (!voltdm->read || !voltdm->write) {
780 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
781 __func__, voltdm->name);
782 return;
783 }
784
785 vc->cfg_channel = 0;
786 if (vc->flags & OMAP_VC_CHANNEL_CFG_MUTANT)
787 vc_cfg_bits = &vc_mutant_channel_cfg;
788 else
789 vc_cfg_bits = &vc_default_channel_cfg;
790
791 /* get PMIC/board specific settings */
792 vc->i2c_slave_addr = voltdm->pmic->i2c_slave_addr;
793 vc->volt_reg_addr = voltdm->pmic->volt_reg_addr;
794 vc->cmd_reg_addr = voltdm->pmic->cmd_reg_addr;
795
796 /* Configure the i2c slave address for this VC */
797 voltdm->rmw(vc->smps_sa_mask,
798 vc->i2c_slave_addr << __ffs(vc->smps_sa_mask),
799 vc->smps_sa_reg);
800 vc->cfg_channel |= vc_cfg_bits->sa;
801
802 /*
803 * Configure the PMIC register addresses.
804 */
805 voltdm->rmw(vc->smps_volra_mask,
806 vc->volt_reg_addr << __ffs(vc->smps_volra_mask),
807 vc->smps_volra_reg);
808 vc->cfg_channel |= vc_cfg_bits->rav;
809
810 if (vc->cmd_reg_addr) {
811 voltdm->rmw(vc->smps_cmdra_mask,
812 vc->cmd_reg_addr << __ffs(vc->smps_cmdra_mask),
813 vc->smps_cmdra_reg);
814 vc->cfg_channel |= vc_cfg_bits->rac;
815 }
816
817 if (vc->cmd_reg_addr == vc->volt_reg_addr)
818 vc->cfg_channel |= vc_cfg_bits->racen;
819
820 /* Set up the on, inactive, retention and off voltage */
821 on_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->on);
822 onlp_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->onlp);
823 ret_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->ret);
824 off_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->off);
825
826 val = ((on_vsel << vc->common->cmd_on_shift) |
827 (onlp_vsel << vc->common->cmd_onlp_shift) |
828 (ret_vsel << vc->common->cmd_ret_shift) |
829 (off_vsel << vc->common->cmd_off_shift));
830 voltdm->write(val, vc->cmdval_reg);
831 vc->cfg_channel |= vc_cfg_bits->cmd;
832
833 /* Channel configuration */
834 omap_vc_config_channel(voltdm);
835
836 omap_vc_i2c_init(voltdm);
837
838 if (cpu_is_omap34xx())
839 omap3_vc_init_channel(voltdm);
840 else if (cpu_is_omap44xx())
841 omap4_vc_init_channel(voltdm);
842}
843
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * OMAP Voltage Controller (VC) interface
4 *
5 * Copyright (C) 2011 Texas Instruments, Inc.
6 */
7#include <linux/kernel.h>
8#include <linux/delay.h>
9#include <linux/init.h>
10#include <linux/bug.h>
11#include <linux/io.h>
12
13#include <asm/div64.h>
14
15#include "iomap.h"
16#include "soc.h"
17#include "voltage.h"
18#include "vc.h"
19#include "prm-regbits-34xx.h"
20#include "prm-regbits-44xx.h"
21#include "prm44xx.h"
22#include "pm.h"
23#include "scrm44xx.h"
24#include "control.h"
25
26#define OMAP4430_VDD_IVA_I2C_DISABLE BIT(14)
27#define OMAP4430_VDD_MPU_I2C_DISABLE BIT(13)
28#define OMAP4430_VDD_CORE_I2C_DISABLE BIT(12)
29#define OMAP4430_VDD_IVA_PRESENCE BIT(9)
30#define OMAP4430_VDD_MPU_PRESENCE BIT(8)
31#define OMAP4430_AUTO_CTRL_VDD_IVA(x) ((x) << 4)
32#define OMAP4430_AUTO_CTRL_VDD_MPU(x) ((x) << 2)
33#define OMAP4430_AUTO_CTRL_VDD_CORE(x) ((x) << 0)
34#define OMAP4430_AUTO_CTRL_VDD_RET 2
35
36#define OMAP4430_VDD_I2C_DISABLE_MASK \
37 (OMAP4430_VDD_IVA_I2C_DISABLE | \
38 OMAP4430_VDD_MPU_I2C_DISABLE | \
39 OMAP4430_VDD_CORE_I2C_DISABLE)
40
41#define OMAP4_VDD_DEFAULT_VAL \
42 (OMAP4430_VDD_I2C_DISABLE_MASK | \
43 OMAP4430_VDD_IVA_PRESENCE | OMAP4430_VDD_MPU_PRESENCE | \
44 OMAP4430_AUTO_CTRL_VDD_IVA(OMAP4430_AUTO_CTRL_VDD_RET) | \
45 OMAP4430_AUTO_CTRL_VDD_MPU(OMAP4430_AUTO_CTRL_VDD_RET) | \
46 OMAP4430_AUTO_CTRL_VDD_CORE(OMAP4430_AUTO_CTRL_VDD_RET))
47
48#define OMAP4_VDD_RET_VAL \
49 (OMAP4_VDD_DEFAULT_VAL & ~OMAP4430_VDD_I2C_DISABLE_MASK)
50
51/**
52 * struct omap_vc_channel_cfg - describe the cfg_channel bitfield
53 * @sa: bit for slave address
54 * @rav: bit for voltage configuration register
55 * @rac: bit for command configuration register
56 * @racen: enable bit for RAC
57 * @cmd: bit for command value set selection
58 *
59 * Channel configuration bits, common for OMAP3+
60 * OMAP3 register: PRM_VC_CH_CONF
61 * OMAP4 register: PRM_VC_CFG_CHANNEL
62 * OMAP5 register: PRM_VC_SMPS_<voltdm>_CONFIG
63 */
64struct omap_vc_channel_cfg {
65 u8 sa;
66 u8 rav;
67 u8 rac;
68 u8 racen;
69 u8 cmd;
70};
71
72static struct omap_vc_channel_cfg vc_default_channel_cfg = {
73 .sa = BIT(0),
74 .rav = BIT(1),
75 .rac = BIT(2),
76 .racen = BIT(3),
77 .cmd = BIT(4),
78};
79
80/*
81 * On OMAP3+, all VC channels have the above default bitfield
82 * configuration, except the OMAP4 MPU channel. This appears
83 * to be a freak accident as every other VC channel has the
84 * default configuration, thus creating a mutant channel config.
85 */
86static struct omap_vc_channel_cfg vc_mutant_channel_cfg = {
87 .sa = BIT(0),
88 .rav = BIT(2),
89 .rac = BIT(3),
90 .racen = BIT(4),
91 .cmd = BIT(1),
92};
93
94static struct omap_vc_channel_cfg *vc_cfg_bits;
95
96/* Default I2C trace length on pcb, 6.3cm. Used for capacitance calculations. */
97static u32 sr_i2c_pcb_length = 63;
98#define CFG_CHANNEL_MASK 0x1f
99
100/**
101 * omap_vc_config_channel - configure VC channel to PMIC mappings
102 * @voltdm: pointer to voltagdomain defining the desired VC channel
103 *
104 * Configures the VC channel to PMIC mappings for the following
105 * PMIC settings
106 * - i2c slave address (SA)
107 * - voltage configuration address (RAV)
108 * - command configuration address (RAC) and enable bit (RACEN)
109 * - command values for ON, ONLP, RET and OFF (CMD)
110 *
111 * This function currently only allows flexible configuration of the
112 * non-default channel. Starting with OMAP4, there are more than 2
113 * channels, with one defined as the default (on OMAP4, it's MPU.)
114 * Only the non-default channel can be configured.
115 */
116static int omap_vc_config_channel(struct voltagedomain *voltdm)
117{
118 struct omap_vc_channel *vc = voltdm->vc;
119
120 /*
121 * For default channel, the only configurable bit is RACEN.
122 * All others must stay at zero (see function comment above.)
123 */
124 if (vc->flags & OMAP_VC_CHANNEL_DEFAULT)
125 vc->cfg_channel &= vc_cfg_bits->racen;
126
127 voltdm->rmw(CFG_CHANNEL_MASK << vc->cfg_channel_sa_shift,
128 vc->cfg_channel << vc->cfg_channel_sa_shift,
129 vc->cfg_channel_reg);
130
131 return 0;
132}
133
134/* Voltage scale and accessory APIs */
135int omap_vc_pre_scale(struct voltagedomain *voltdm,
136 unsigned long target_volt,
137 u8 *target_vsel, u8 *current_vsel)
138{
139 struct omap_vc_channel *vc = voltdm->vc;
140 u32 vc_cmdval;
141
142 /* Check if sufficient pmic info is available for this vdd */
143 if (!voltdm->pmic) {
144 pr_err("%s: Insufficient pmic info to scale the vdd_%s\n",
145 __func__, voltdm->name);
146 return -EINVAL;
147 }
148
149 if (!voltdm->pmic->uv_to_vsel) {
150 pr_err("%s: PMIC function to convert voltage in uV to vsel not registered. Hence unable to scale voltage for vdd_%s\n",
151 __func__, voltdm->name);
152 return -ENODATA;
153 }
154
155 if (!voltdm->read || !voltdm->write) {
156 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
157 __func__, voltdm->name);
158 return -EINVAL;
159 }
160
161 *target_vsel = voltdm->pmic->uv_to_vsel(target_volt);
162 *current_vsel = voltdm->pmic->uv_to_vsel(voltdm->nominal_volt);
163
164 /* Setting the ON voltage to the new target voltage */
165 vc_cmdval = voltdm->read(vc->cmdval_reg);
166 vc_cmdval &= ~vc->common->cmd_on_mask;
167 vc_cmdval |= (*target_vsel << vc->common->cmd_on_shift);
168 voltdm->write(vc_cmdval, vc->cmdval_reg);
169
170 voltdm->vc_param->on = target_volt;
171
172 omap_vp_update_errorgain(voltdm, target_volt);
173
174 return 0;
175}
176
177void omap_vc_post_scale(struct voltagedomain *voltdm,
178 unsigned long target_volt,
179 u8 target_vsel, u8 current_vsel)
180{
181 u32 smps_steps = 0, smps_delay = 0;
182
183 smps_steps = abs(target_vsel - current_vsel);
184 /* SMPS slew rate / step size. 2us added as buffer. */
185 smps_delay = ((smps_steps * voltdm->pmic->step_size) /
186 voltdm->pmic->slew_rate) + 2;
187 udelay(smps_delay);
188}
189
190/* vc_bypass_scale - VC bypass method of voltage scaling */
191int omap_vc_bypass_scale(struct voltagedomain *voltdm,
192 unsigned long target_volt)
193{
194 struct omap_vc_channel *vc = voltdm->vc;
195 u32 loop_cnt = 0, retries_cnt = 0;
196 u32 vc_valid, vc_bypass_val_reg, vc_bypass_value;
197 u8 target_vsel, current_vsel;
198 int ret;
199
200 ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, ¤t_vsel);
201 if (ret)
202 return ret;
203
204 vc_valid = vc->common->valid;
205 vc_bypass_val_reg = vc->common->bypass_val_reg;
206 vc_bypass_value = (target_vsel << vc->common->data_shift) |
207 (vc->volt_reg_addr << vc->common->regaddr_shift) |
208 (vc->i2c_slave_addr << vc->common->slaveaddr_shift);
209
210 voltdm->write(vc_bypass_value, vc_bypass_val_reg);
211 voltdm->write(vc_bypass_value | vc_valid, vc_bypass_val_reg);
212
213 vc_bypass_value = voltdm->read(vc_bypass_val_reg);
214 /*
215 * Loop till the bypass command is acknowledged from the SMPS.
216 * NOTE: This is legacy code. The loop count and retry count needs
217 * to be revisited.
218 */
219 while (!(vc_bypass_value & vc_valid)) {
220 loop_cnt++;
221
222 if (retries_cnt > 10) {
223 pr_warn("%s: Retry count exceeded\n", __func__);
224 return -ETIMEDOUT;
225 }
226
227 if (loop_cnt > 50) {
228 retries_cnt++;
229 loop_cnt = 0;
230 udelay(10);
231 }
232 vc_bypass_value = voltdm->read(vc_bypass_val_reg);
233 }
234
235 omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
236 return 0;
237}
238
239/* Convert microsecond value to number of 32kHz clock cycles */
240static inline u32 omap_usec_to_32k(u32 usec)
241{
242 return DIV_ROUND_UP_ULL(32768ULL * (u64)usec, 1000000ULL);
243}
244
245struct omap3_vc_timings {
246 u32 voltsetup1;
247 u32 voltsetup2;
248};
249
250struct omap3_vc {
251 struct voltagedomain *vd;
252 u32 voltctrl;
253 u32 voltsetup1;
254 u32 voltsetup2;
255 struct omap3_vc_timings timings[2];
256};
257static struct omap3_vc vc;
258
259void omap3_vc_set_pmic_signaling(int core_next_state)
260{
261 struct voltagedomain *vd = vc.vd;
262 struct omap3_vc_timings *c = vc.timings;
263 u32 voltctrl, voltsetup1, voltsetup2;
264
265 voltctrl = vc.voltctrl;
266 voltsetup1 = vc.voltsetup1;
267 voltsetup2 = vc.voltsetup2;
268
269 switch (core_next_state) {
270 case PWRDM_POWER_OFF:
271 voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_RET |
272 OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP);
273 voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_OFF;
274 if (voltctrl & OMAP3430_PRM_VOLTCTRL_SEL_OFF)
275 voltsetup2 = c->voltsetup2;
276 else
277 voltsetup1 = c->voltsetup1;
278 break;
279 case PWRDM_POWER_RET:
280 default:
281 c++;
282 voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_OFF |
283 OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP);
284 voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_RET;
285 voltsetup1 = c->voltsetup1;
286 break;
287 }
288
289 if (voltctrl != vc.voltctrl) {
290 vd->write(voltctrl, OMAP3_PRM_VOLTCTRL_OFFSET);
291 vc.voltctrl = voltctrl;
292 }
293 if (voltsetup1 != vc.voltsetup1) {
294 vd->write(c->voltsetup1,
295 OMAP3_PRM_VOLTSETUP1_OFFSET);
296 vc.voltsetup1 = voltsetup1;
297 }
298 if (voltsetup2 != vc.voltsetup2) {
299 vd->write(c->voltsetup2,
300 OMAP3_PRM_VOLTSETUP2_OFFSET);
301 vc.voltsetup2 = voltsetup2;
302 }
303}
304
305void omap4_vc_set_pmic_signaling(int core_next_state)
306{
307 struct voltagedomain *vd = vc.vd;
308 u32 val;
309
310 if (!vd)
311 return;
312
313 switch (core_next_state) {
314 case PWRDM_POWER_RET:
315 val = OMAP4_VDD_RET_VAL;
316 break;
317 default:
318 val = OMAP4_VDD_DEFAULT_VAL;
319 break;
320 }
321
322 vd->write(val, OMAP4_PRM_VOLTCTRL_OFFSET);
323}
324
325/*
326 * Configure signal polarity for sys_clkreq and sys_off_mode pins
327 * as the default values are wrong and can cause the system to hang
328 * if any twl4030 scripts are loaded.
329 */
330static void __init omap3_vc_init_pmic_signaling(struct voltagedomain *voltdm)
331{
332 u32 val;
333
334 if (vc.vd)
335 return;
336
337 vc.vd = voltdm;
338
339 val = voltdm->read(OMAP3_PRM_POLCTRL_OFFSET);
340 if (!(val & OMAP3430_PRM_POLCTRL_CLKREQ_POL) ||
341 (val & OMAP3430_PRM_POLCTRL_OFFMODE_POL)) {
342 val |= OMAP3430_PRM_POLCTRL_CLKREQ_POL;
343 val &= ~OMAP3430_PRM_POLCTRL_OFFMODE_POL;
344 pr_debug("PM: fixing sys_clkreq and sys_off_mode polarity to 0x%x\n",
345 val);
346 voltdm->write(val, OMAP3_PRM_POLCTRL_OFFSET);
347 }
348
349 /*
350 * By default let's use I2C4 signaling for retention idle
351 * and sys_off_mode pin signaling for off idle. This way we
352 * have sys_clk_req pin go down for retention and both
353 * sys_clk_req and sys_off_mode pins will go down for off
354 * idle. And we can also scale voltages to zero for off-idle.
355 * Note that no actual voltage scaling during off-idle will
356 * happen unless the board specific twl4030 PMIC scripts are
357 * loaded. See also omap_vc_i2c_init for comments regarding
358 * erratum i531.
359 */
360 val = voltdm->read(OMAP3_PRM_VOLTCTRL_OFFSET);
361 if (!(val & OMAP3430_PRM_VOLTCTRL_SEL_OFF)) {
362 val |= OMAP3430_PRM_VOLTCTRL_SEL_OFF;
363 pr_debug("PM: setting voltctrl sys_off_mode signaling to 0x%x\n",
364 val);
365 voltdm->write(val, OMAP3_PRM_VOLTCTRL_OFFSET);
366 }
367 vc.voltctrl = val;
368
369 omap3_vc_set_pmic_signaling(PWRDM_POWER_ON);
370}
371
372static void omap3_init_voltsetup1(struct voltagedomain *voltdm,
373 struct omap3_vc_timings *c, u32 idle)
374{
375 unsigned long val;
376
377 val = (voltdm->vc_param->on - idle) / voltdm->pmic->slew_rate;
378 val *= voltdm->sys_clk.rate / 8 / 1000000 + 1;
379 val <<= __ffs(voltdm->vfsm->voltsetup_mask);
380 c->voltsetup1 &= ~voltdm->vfsm->voltsetup_mask;
381 c->voltsetup1 |= val;
382}
383
384/**
385 * omap3_set_i2c_timings - sets i2c sleep timings for a channel
386 * @voltdm: channel to configure
387 * @off_mode: select whether retention or off mode values used
388 *
389 * Calculates and sets up voltage controller to use I2C based
390 * voltage scaling for sleep modes. This can be used for either off mode
391 * or retention. Off mode has additionally an option to use sys_off_mode
392 * pad, which uses a global signal to program the whole power IC to
393 * off-mode.
394 *
395 * Note that pmic is not controlling the voltage scaling during
396 * retention signaled over I2C4, so we can keep voltsetup2 as 0.
397 * And the oscillator is not shut off over I2C4, so no need to
398 * set clksetup.
399 */
400static void omap3_set_i2c_timings(struct voltagedomain *voltdm)
401{
402 struct omap3_vc_timings *c = vc.timings;
403
404 /* Configure PRWDM_POWER_OFF over I2C4 */
405 omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->off);
406 c++;
407 /* Configure PRWDM_POWER_RET over I2C4 */
408 omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->ret);
409}
410
411/**
412 * omap3_set_off_timings - sets off-mode timings for a channel
413 * @voltdm: channel to configure
414 *
415 * Calculates and sets up off-mode timings for a channel. Off-mode
416 * can use either I2C based voltage scaling, or alternatively
417 * sys_off_mode pad can be used to send a global command to power IC.n,
418 * sys_off_mode has the additional benefit that voltages can be
419 * scaled to zero volt level with TWL4030 / TWL5030, I2C can only
420 * scale to 600mV.
421 *
422 * Note that omap is not controlling the voltage scaling during
423 * off idle signaled by sys_off_mode, so we can keep voltsetup1
424 * as 0.
425 */
426static void omap3_set_off_timings(struct voltagedomain *voltdm)
427{
428 struct omap3_vc_timings *c = vc.timings;
429 u32 tstart, tshut, clksetup, voltoffset;
430
431 if (c->voltsetup2)
432 return;
433
434 omap_pm_get_oscillator(&tstart, &tshut);
435 if (tstart == ULONG_MAX) {
436 pr_debug("PM: oscillator start-up time not initialized, using 10ms\n");
437 clksetup = omap_usec_to_32k(10000);
438 } else {
439 clksetup = omap_usec_to_32k(tstart);
440 }
441
442 /*
443 * For twl4030 errata 27, we need to allow minimum ~488.32 us wait to
444 * switch from HFCLKIN to internal oscillator. That means timings
445 * have voltoffset fixed to 0xa in rounded up 32 KiHz cycles. And
446 * that means we can calculate the value based on the oscillator
447 * start-up time since voltoffset2 = clksetup - voltoffset.
448 */
449 voltoffset = omap_usec_to_32k(488);
450 c->voltsetup2 = clksetup - voltoffset;
451 voltdm->write(clksetup, OMAP3_PRM_CLKSETUP_OFFSET);
452 voltdm->write(voltoffset, OMAP3_PRM_VOLTOFFSET_OFFSET);
453}
454
455static void __init omap3_vc_init_channel(struct voltagedomain *voltdm)
456{
457 omap3_vc_init_pmic_signaling(voltdm);
458 omap3_set_off_timings(voltdm);
459 omap3_set_i2c_timings(voltdm);
460}
461
462/**
463 * omap4_calc_volt_ramp - calculates voltage ramping delays on omap4
464 * @voltdm: channel to calculate values for
465 * @voltage_diff: voltage difference in microvolts
466 *
467 * Calculates voltage ramp prescaler + counter values for a voltage
468 * difference on omap4. Returns a field value suitable for writing to
469 * VOLTSETUP register for a channel in following format:
470 * bits[8:9] prescaler ... bits[0:5] counter. See OMAP4 TRM for reference.
471 */
472static u32 omap4_calc_volt_ramp(struct voltagedomain *voltdm, u32 voltage_diff)
473{
474 u32 prescaler;
475 u32 cycles;
476 u32 time;
477
478 time = voltage_diff / voltdm->pmic->slew_rate;
479
480 cycles = voltdm->sys_clk.rate / 1000 * time / 1000;
481
482 cycles /= 64;
483 prescaler = 0;
484
485 /* shift to next prescaler until no overflow */
486
487 /* scale for div 256 = 64 * 4 */
488 if (cycles > 63) {
489 cycles /= 4;
490 prescaler++;
491 }
492
493 /* scale for div 512 = 256 * 2 */
494 if (cycles > 63) {
495 cycles /= 2;
496 prescaler++;
497 }
498
499 /* scale for div 2048 = 512 * 4 */
500 if (cycles > 63) {
501 cycles /= 4;
502 prescaler++;
503 }
504
505 /* check for overflow => invalid ramp time */
506 if (cycles > 63) {
507 pr_warn("%s: invalid setuptime for vdd_%s\n", __func__,
508 voltdm->name);
509 return 0;
510 }
511
512 cycles++;
513
514 return (prescaler << OMAP4430_RAMP_UP_PRESCAL_SHIFT) |
515 (cycles << OMAP4430_RAMP_UP_COUNT_SHIFT);
516}
517
518/**
519 * omap4_usec_to_val_scrm - convert microsecond value to SCRM module bitfield
520 * @usec: microseconds
521 * @shift: number of bits to shift left
522 * @mask: bitfield mask
523 *
524 * Converts microsecond value to OMAP4 SCRM bitfield. Bitfield is
525 * shifted to requested position, and checked agains the mask value.
526 * If larger, forced to the max value of the field (i.e. the mask itself.)
527 * Returns the SCRM bitfield value.
528 */
529static u32 omap4_usec_to_val_scrm(u32 usec, int shift, u32 mask)
530{
531 u32 val;
532
533 val = omap_usec_to_32k(usec) << shift;
534
535 /* Check for overflow, if yes, force to max value */
536 if (val > mask)
537 val = mask;
538
539 return val;
540}
541
542/**
543 * omap4_set_timings - set voltage ramp timings for a channel
544 * @voltdm: channel to configure
545 * @off_mode: whether off-mode values are used
546 *
547 * Calculates and sets the voltage ramp up / down values for a channel.
548 */
549static void omap4_set_timings(struct voltagedomain *voltdm, bool off_mode)
550{
551 u32 val;
552 u32 ramp;
553 int offset;
554 u32 tstart, tshut;
555
556 if (off_mode) {
557 ramp = omap4_calc_volt_ramp(voltdm,
558 voltdm->vc_param->on - voltdm->vc_param->off);
559 offset = voltdm->vfsm->voltsetup_off_reg;
560 } else {
561 ramp = omap4_calc_volt_ramp(voltdm,
562 voltdm->vc_param->on - voltdm->vc_param->ret);
563 offset = voltdm->vfsm->voltsetup_reg;
564 }
565
566 if (!ramp)
567 return;
568
569 val = voltdm->read(offset);
570
571 val |= ramp << OMAP4430_RAMP_DOWN_COUNT_SHIFT;
572
573 val |= ramp << OMAP4430_RAMP_UP_COUNT_SHIFT;
574
575 voltdm->write(val, offset);
576
577 omap_pm_get_oscillator(&tstart, &tshut);
578
579 val = omap4_usec_to_val_scrm(tstart, OMAP4_SETUPTIME_SHIFT,
580 OMAP4_SETUPTIME_MASK);
581 val |= omap4_usec_to_val_scrm(tshut, OMAP4_DOWNTIME_SHIFT,
582 OMAP4_DOWNTIME_MASK);
583
584 writel_relaxed(val, OMAP4_SCRM_CLKSETUPTIME);
585}
586
587static void __init omap4_vc_init_pmic_signaling(struct voltagedomain *voltdm)
588{
589 if (vc.vd)
590 return;
591
592 vc.vd = voltdm;
593 voltdm->write(OMAP4_VDD_DEFAULT_VAL, OMAP4_PRM_VOLTCTRL_OFFSET);
594}
595
596/* OMAP4 specific voltage init functions */
597static void __init omap4_vc_init_channel(struct voltagedomain *voltdm)
598{
599 omap4_vc_init_pmic_signaling(voltdm);
600 omap4_set_timings(voltdm, true);
601 omap4_set_timings(voltdm, false);
602}
603
604struct i2c_init_data {
605 u8 loadbits;
606 u8 load;
607 u8 hsscll_38_4;
608 u8 hsscll_26;
609 u8 hsscll_19_2;
610 u8 hsscll_16_8;
611 u8 hsscll_12;
612};
613
614static const struct i2c_init_data omap4_i2c_timing_data[] __initconst = {
615 {
616 .load = 50,
617 .loadbits = 0x3,
618 .hsscll_38_4 = 13,
619 .hsscll_26 = 11,
620 .hsscll_19_2 = 9,
621 .hsscll_16_8 = 9,
622 .hsscll_12 = 8,
623 },
624 {
625 .load = 25,
626 .loadbits = 0x2,
627 .hsscll_38_4 = 13,
628 .hsscll_26 = 11,
629 .hsscll_19_2 = 9,
630 .hsscll_16_8 = 9,
631 .hsscll_12 = 8,
632 },
633 {
634 .load = 12,
635 .loadbits = 0x1,
636 .hsscll_38_4 = 11,
637 .hsscll_26 = 10,
638 .hsscll_19_2 = 9,
639 .hsscll_16_8 = 9,
640 .hsscll_12 = 8,
641 },
642 {
643 .load = 0,
644 .loadbits = 0x0,
645 .hsscll_38_4 = 12,
646 .hsscll_26 = 10,
647 .hsscll_19_2 = 9,
648 .hsscll_16_8 = 8,
649 .hsscll_12 = 8,
650 },
651};
652
653/**
654 * omap4_vc_i2c_timing_init - sets up board I2C timing parameters
655 * @voltdm: voltagedomain pointer to get data from
656 *
657 * Use PMIC + board supplied settings for calculating the total I2C
658 * channel capacitance and set the timing parameters based on this.
659 * Pre-calculated values are provided in data tables, as it is not
660 * too straightforward to calculate these runtime.
661 */
662static void __init omap4_vc_i2c_timing_init(struct voltagedomain *voltdm)
663{
664 u32 capacitance;
665 u32 val;
666 u16 hsscll;
667 const struct i2c_init_data *i2c_data;
668
669 if (!voltdm->pmic->i2c_high_speed) {
670 pr_info("%s: using bootloader low-speed timings\n", __func__);
671 return;
672 }
673
674 /* PCB trace capacitance, 0.125pF / mm => mm / 8 */
675 capacitance = DIV_ROUND_UP(sr_i2c_pcb_length, 8);
676
677 /* OMAP pad capacitance */
678 capacitance += 4;
679
680 /* PMIC pad capacitance */
681 capacitance += voltdm->pmic->i2c_pad_load;
682
683 /* Search for capacitance match in the table */
684 i2c_data = omap4_i2c_timing_data;
685
686 while (i2c_data->load > capacitance)
687 i2c_data++;
688
689 /* Select proper values based on sysclk frequency */
690 switch (voltdm->sys_clk.rate) {
691 case 38400000:
692 hsscll = i2c_data->hsscll_38_4;
693 break;
694 case 26000000:
695 hsscll = i2c_data->hsscll_26;
696 break;
697 case 19200000:
698 hsscll = i2c_data->hsscll_19_2;
699 break;
700 case 16800000:
701 hsscll = i2c_data->hsscll_16_8;
702 break;
703 case 12000000:
704 hsscll = i2c_data->hsscll_12;
705 break;
706 default:
707 pr_warn("%s: unsupported sysclk rate: %d!\n", __func__,
708 voltdm->sys_clk.rate);
709 return;
710 }
711
712 /* Loadbits define pull setup for the I2C channels */
713 val = i2c_data->loadbits << 25 | i2c_data->loadbits << 29;
714
715 /* Write to SYSCTRL_PADCONF_WKUP_CTRL_I2C_2 to setup I2C pull */
716 writel_relaxed(val, OMAP2_L4_IO_ADDRESS(OMAP4_CTRL_MODULE_PAD_WKUP +
717 OMAP4_CTRL_MODULE_PAD_WKUP_CONTROL_I2C_2));
718
719 /* HSSCLH can always be zero */
720 val = hsscll << OMAP4430_HSSCLL_SHIFT;
721 val |= (0x28 << OMAP4430_SCLL_SHIFT | 0x2c << OMAP4430_SCLH_SHIFT);
722
723 /* Write setup times to I2C config register */
724 voltdm->write(val, OMAP4_PRM_VC_CFG_I2C_CLK_OFFSET);
725}
726
727
728
729/**
730 * omap_vc_i2c_init - initialize I2C interface to PMIC
731 * @voltdm: voltage domain containing VC data
732 *
733 * Use PMIC supplied settings for I2C high-speed mode and
734 * master code (if set) and program the VC I2C configuration
735 * register.
736 *
737 * The VC I2C configuration is common to all VC channels,
738 * so this function only configures I2C for the first VC
739 * channel registers. All other VC channels will use the
740 * same configuration.
741 */
742static void __init omap_vc_i2c_init(struct voltagedomain *voltdm)
743{
744 struct omap_vc_channel *vc = voltdm->vc;
745 static bool initialized;
746 static bool i2c_high_speed;
747 u8 mcode;
748
749 if (initialized) {
750 if (voltdm->pmic->i2c_high_speed != i2c_high_speed)
751 pr_warn("%s: I2C config for vdd_%s does not match other channels (%u).\n",
752 __func__, voltdm->name, i2c_high_speed);
753 return;
754 }
755
756 /*
757 * Note that for omap3 OMAP3430_SREN_MASK clears SREN to work around
758 * erratum i531 "Extra Power Consumed When Repeated Start Operation
759 * Mode Is Enabled on I2C Interface Dedicated for Smart Reflex (I2C4)".
760 * Otherwise I2C4 eventually leads into about 23mW extra power being
761 * consumed even during off idle using VMODE.
762 */
763 i2c_high_speed = voltdm->pmic->i2c_high_speed;
764 if (i2c_high_speed)
765 voltdm->rmw(vc->common->i2c_cfg_clear_mask,
766 vc->common->i2c_cfg_hsen_mask,
767 vc->common->i2c_cfg_reg);
768
769 mcode = voltdm->pmic->i2c_mcode;
770 if (mcode)
771 voltdm->rmw(vc->common->i2c_mcode_mask,
772 mcode << __ffs(vc->common->i2c_mcode_mask),
773 vc->common->i2c_cfg_reg);
774
775 if (cpu_is_omap44xx())
776 omap4_vc_i2c_timing_init(voltdm);
777
778 initialized = true;
779}
780
781/**
782 * omap_vc_calc_vsel - calculate vsel value for a channel
783 * @voltdm: channel to calculate value for
784 * @uvolt: microvolt value to convert to vsel
785 *
786 * Converts a microvolt value to vsel value for the used PMIC.
787 * This checks whether the microvolt value is out of bounds, and
788 * adjusts the value accordingly. If unsupported value detected,
789 * warning is thrown.
790 */
791static u8 omap_vc_calc_vsel(struct voltagedomain *voltdm, u32 uvolt)
792{
793 if (voltdm->pmic->vddmin > uvolt)
794 uvolt = voltdm->pmic->vddmin;
795 if (voltdm->pmic->vddmax < uvolt) {
796 WARN(1, "%s: voltage not supported by pmic: %u vs max %u\n",
797 __func__, uvolt, voltdm->pmic->vddmax);
798 /* Lets try maximum value anyway */
799 uvolt = voltdm->pmic->vddmax;
800 }
801
802 return voltdm->pmic->uv_to_vsel(uvolt);
803}
804
805void __init omap_vc_init_channel(struct voltagedomain *voltdm)
806{
807 struct omap_vc_channel *vc = voltdm->vc;
808 u8 on_vsel, onlp_vsel, ret_vsel, off_vsel;
809 u32 val;
810
811 if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
812 pr_err("%s: No PMIC info for vdd_%s\n", __func__, voltdm->name);
813 return;
814 }
815
816 if (!voltdm->read || !voltdm->write) {
817 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
818 __func__, voltdm->name);
819 return;
820 }
821
822 vc->cfg_channel = 0;
823 if (vc->flags & OMAP_VC_CHANNEL_CFG_MUTANT)
824 vc_cfg_bits = &vc_mutant_channel_cfg;
825 else
826 vc_cfg_bits = &vc_default_channel_cfg;
827
828 /* get PMIC/board specific settings */
829 vc->i2c_slave_addr = voltdm->pmic->i2c_slave_addr;
830 vc->volt_reg_addr = voltdm->pmic->volt_reg_addr;
831 vc->cmd_reg_addr = voltdm->pmic->cmd_reg_addr;
832
833 /* Configure the i2c slave address for this VC */
834 voltdm->rmw(vc->smps_sa_mask,
835 vc->i2c_slave_addr << __ffs(vc->smps_sa_mask),
836 vc->smps_sa_reg);
837 vc->cfg_channel |= vc_cfg_bits->sa;
838
839 /*
840 * Configure the PMIC register addresses.
841 */
842 voltdm->rmw(vc->smps_volra_mask,
843 vc->volt_reg_addr << __ffs(vc->smps_volra_mask),
844 vc->smps_volra_reg);
845 vc->cfg_channel |= vc_cfg_bits->rav;
846
847 if (vc->cmd_reg_addr) {
848 voltdm->rmw(vc->smps_cmdra_mask,
849 vc->cmd_reg_addr << __ffs(vc->smps_cmdra_mask),
850 vc->smps_cmdra_reg);
851 vc->cfg_channel |= vc_cfg_bits->rac;
852 }
853
854 if (vc->cmd_reg_addr == vc->volt_reg_addr)
855 vc->cfg_channel |= vc_cfg_bits->racen;
856
857 /* Set up the on, inactive, retention and off voltage */
858 on_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->on);
859 onlp_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->onlp);
860 ret_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->ret);
861 off_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->off);
862
863 val = ((on_vsel << vc->common->cmd_on_shift) |
864 (onlp_vsel << vc->common->cmd_onlp_shift) |
865 (ret_vsel << vc->common->cmd_ret_shift) |
866 (off_vsel << vc->common->cmd_off_shift));
867 voltdm->write(val, vc->cmdval_reg);
868 vc->cfg_channel |= vc_cfg_bits->cmd;
869
870 /* Channel configuration */
871 omap_vc_config_channel(voltdm);
872
873 omap_vc_i2c_init(voltdm);
874
875 if (cpu_is_omap34xx())
876 omap3_vc_init_channel(voltdm);
877 else if (cpu_is_omap44xx())
878 omap4_vc_init_channel(voltdm);
879}