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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
805#ifdef CONFIG_PM
806/**
807 * omap_pm_setup_sr_i2c_pcb_length - set length of SR I2C traces on PCB
808 * @mm: length of the PCB trace in millimetres
809 *
810 * Sets the PCB trace length for the I2C channel. By default uses 63mm.
811 * This is needed for properly calculating the capacitance value for
812 * the PCB trace, and for setting the SR I2C channel timing parameters.
813 */
814void __init omap_pm_setup_sr_i2c_pcb_length(u32 mm)
815{
816 sr_i2c_pcb_length = mm;
817}
818#endif
819
820void __init omap_vc_init_channel(struct voltagedomain *voltdm)
821{
822 struct omap_vc_channel *vc = voltdm->vc;
823 u8 on_vsel, onlp_vsel, ret_vsel, off_vsel;
824 u32 val;
825
826 if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
827 pr_err("%s: No PMIC info for vdd_%s\n", __func__, voltdm->name);
828 return;
829 }
830
831 if (!voltdm->read || !voltdm->write) {
832 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
833 __func__, voltdm->name);
834 return;
835 }
836
837 vc->cfg_channel = 0;
838 if (vc->flags & OMAP_VC_CHANNEL_CFG_MUTANT)
839 vc_cfg_bits = &vc_mutant_channel_cfg;
840 else
841 vc_cfg_bits = &vc_default_channel_cfg;
842
843 /* get PMIC/board specific settings */
844 vc->i2c_slave_addr = voltdm->pmic->i2c_slave_addr;
845 vc->volt_reg_addr = voltdm->pmic->volt_reg_addr;
846 vc->cmd_reg_addr = voltdm->pmic->cmd_reg_addr;
847
848 /* Configure the i2c slave address for this VC */
849 voltdm->rmw(vc->smps_sa_mask,
850 vc->i2c_slave_addr << __ffs(vc->smps_sa_mask),
851 vc->smps_sa_reg);
852 vc->cfg_channel |= vc_cfg_bits->sa;
853
854 /*
855 * Configure the PMIC register addresses.
856 */
857 voltdm->rmw(vc->smps_volra_mask,
858 vc->volt_reg_addr << __ffs(vc->smps_volra_mask),
859 vc->smps_volra_reg);
860 vc->cfg_channel |= vc_cfg_bits->rav;
861
862 if (vc->cmd_reg_addr) {
863 voltdm->rmw(vc->smps_cmdra_mask,
864 vc->cmd_reg_addr << __ffs(vc->smps_cmdra_mask),
865 vc->smps_cmdra_reg);
866 vc->cfg_channel |= vc_cfg_bits->rac;
867 }
868
869 if (vc->cmd_reg_addr == vc->volt_reg_addr)
870 vc->cfg_channel |= vc_cfg_bits->racen;
871
872 /* Set up the on, inactive, retention and off voltage */
873 on_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->on);
874 onlp_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->onlp);
875 ret_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->ret);
876 off_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->off);
877
878 val = ((on_vsel << vc->common->cmd_on_shift) |
879 (onlp_vsel << vc->common->cmd_onlp_shift) |
880 (ret_vsel << vc->common->cmd_ret_shift) |
881 (off_vsel << vc->common->cmd_off_shift));
882 voltdm->write(val, vc->cmdval_reg);
883 vc->cfg_channel |= vc_cfg_bits->cmd;
884
885 /* Channel configuration */
886 omap_vc_config_channel(voltdm);
887
888 omap_vc_i2c_init(voltdm);
889
890 if (cpu_is_omap34xx())
891 omap3_vc_init_channel(voltdm);
892 else if (cpu_is_omap44xx())
893 omap4_vc_init_channel(voltdm);
894}
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#define OMAP4430_VDD_IVA_I2C_DISABLE BIT(14)
30#define OMAP4430_VDD_MPU_I2C_DISABLE BIT(13)
31#define OMAP4430_VDD_CORE_I2C_DISABLE BIT(12)
32#define OMAP4430_VDD_IVA_PRESENCE BIT(9)
33#define OMAP4430_VDD_MPU_PRESENCE BIT(8)
34#define OMAP4430_AUTO_CTRL_VDD_IVA(x) ((x) << 4)
35#define OMAP4430_AUTO_CTRL_VDD_MPU(x) ((x) << 2)
36#define OMAP4430_AUTO_CTRL_VDD_CORE(x) ((x) << 0)
37#define OMAP4430_AUTO_CTRL_VDD_RET 2
38
39#define OMAP4430_VDD_I2C_DISABLE_MASK \
40 (OMAP4430_VDD_IVA_I2C_DISABLE | \
41 OMAP4430_VDD_MPU_I2C_DISABLE | \
42 OMAP4430_VDD_CORE_I2C_DISABLE)
43
44#define OMAP4_VDD_DEFAULT_VAL \
45 (OMAP4430_VDD_I2C_DISABLE_MASK | \
46 OMAP4430_VDD_IVA_PRESENCE | OMAP4430_VDD_MPU_PRESENCE | \
47 OMAP4430_AUTO_CTRL_VDD_IVA(OMAP4430_AUTO_CTRL_VDD_RET) | \
48 OMAP4430_AUTO_CTRL_VDD_MPU(OMAP4430_AUTO_CTRL_VDD_RET) | \
49 OMAP4430_AUTO_CTRL_VDD_CORE(OMAP4430_AUTO_CTRL_VDD_RET))
50
51#define OMAP4_VDD_RET_VAL \
52 (OMAP4_VDD_DEFAULT_VAL & ~OMAP4430_VDD_I2C_DISABLE_MASK)
53
54/**
55 * struct omap_vc_channel_cfg - describe the cfg_channel bitfield
56 * @sa: bit for slave address
57 * @rav: bit for voltage configuration register
58 * @rac: bit for command configuration register
59 * @racen: enable bit for RAC
60 * @cmd: bit for command value set selection
61 *
62 * Channel configuration bits, common for OMAP3+
63 * OMAP3 register: PRM_VC_CH_CONF
64 * OMAP4 register: PRM_VC_CFG_CHANNEL
65 * OMAP5 register: PRM_VC_SMPS_<voltdm>_CONFIG
66 */
67struct omap_vc_channel_cfg {
68 u8 sa;
69 u8 rav;
70 u8 rac;
71 u8 racen;
72 u8 cmd;
73};
74
75static struct omap_vc_channel_cfg vc_default_channel_cfg = {
76 .sa = BIT(0),
77 .rav = BIT(1),
78 .rac = BIT(2),
79 .racen = BIT(3),
80 .cmd = BIT(4),
81};
82
83/*
84 * On OMAP3+, all VC channels have the above default bitfield
85 * configuration, except the OMAP4 MPU channel. This appears
86 * to be a freak accident as every other VC channel has the
87 * default configuration, thus creating a mutant channel config.
88 */
89static struct omap_vc_channel_cfg vc_mutant_channel_cfg = {
90 .sa = BIT(0),
91 .rav = BIT(2),
92 .rac = BIT(3),
93 .racen = BIT(4),
94 .cmd = BIT(1),
95};
96
97static struct omap_vc_channel_cfg *vc_cfg_bits;
98
99/* Default I2C trace length on pcb, 6.3cm. Used for capacitance calculations. */
100static u32 sr_i2c_pcb_length = 63;
101#define CFG_CHANNEL_MASK 0x1f
102
103/**
104 * omap_vc_config_channel - configure VC channel to PMIC mappings
105 * @voltdm: pointer to voltagdomain defining the desired VC channel
106 *
107 * Configures the VC channel to PMIC mappings for the following
108 * PMIC settings
109 * - i2c slave address (SA)
110 * - voltage configuration address (RAV)
111 * - command configuration address (RAC) and enable bit (RACEN)
112 * - command values for ON, ONLP, RET and OFF (CMD)
113 *
114 * This function currently only allows flexible configuration of the
115 * non-default channel. Starting with OMAP4, there are more than 2
116 * channels, with one defined as the default (on OMAP4, it's MPU.)
117 * Only the non-default channel can be configured.
118 */
119static int omap_vc_config_channel(struct voltagedomain *voltdm)
120{
121 struct omap_vc_channel *vc = voltdm->vc;
122
123 /*
124 * For default channel, the only configurable bit is RACEN.
125 * All others must stay at zero (see function comment above.)
126 */
127 if (vc->flags & OMAP_VC_CHANNEL_DEFAULT)
128 vc->cfg_channel &= vc_cfg_bits->racen;
129
130 voltdm->rmw(CFG_CHANNEL_MASK << vc->cfg_channel_sa_shift,
131 vc->cfg_channel << vc->cfg_channel_sa_shift,
132 vc->cfg_channel_reg);
133
134 return 0;
135}
136
137/* Voltage scale and accessory APIs */
138int omap_vc_pre_scale(struct voltagedomain *voltdm,
139 unsigned long target_volt,
140 u8 *target_vsel, u8 *current_vsel)
141{
142 struct omap_vc_channel *vc = voltdm->vc;
143 u32 vc_cmdval;
144
145 /* Check if sufficient pmic info is available for this vdd */
146 if (!voltdm->pmic) {
147 pr_err("%s: Insufficient pmic info to scale the vdd_%s\n",
148 __func__, voltdm->name);
149 return -EINVAL;
150 }
151
152 if (!voltdm->pmic->uv_to_vsel) {
153 pr_err("%s: PMIC function to convert voltage in uV to vsel not registered. Hence unable to scale voltage for vdd_%s\n",
154 __func__, voltdm->name);
155 return -ENODATA;
156 }
157
158 if (!voltdm->read || !voltdm->write) {
159 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
160 __func__, voltdm->name);
161 return -EINVAL;
162 }
163
164 *target_vsel = voltdm->pmic->uv_to_vsel(target_volt);
165 *current_vsel = voltdm->pmic->uv_to_vsel(voltdm->nominal_volt);
166
167 /* Setting the ON voltage to the new target voltage */
168 vc_cmdval = voltdm->read(vc->cmdval_reg);
169 vc_cmdval &= ~vc->common->cmd_on_mask;
170 vc_cmdval |= (*target_vsel << vc->common->cmd_on_shift);
171 voltdm->write(vc_cmdval, vc->cmdval_reg);
172
173 voltdm->vc_param->on = target_volt;
174
175 omap_vp_update_errorgain(voltdm, target_volt);
176
177 return 0;
178}
179
180void omap_vc_post_scale(struct voltagedomain *voltdm,
181 unsigned long target_volt,
182 u8 target_vsel, u8 current_vsel)
183{
184 u32 smps_steps = 0, smps_delay = 0;
185
186 smps_steps = abs(target_vsel - current_vsel);
187 /* SMPS slew rate / step size. 2us added as buffer. */
188 smps_delay = ((smps_steps * voltdm->pmic->step_size) /
189 voltdm->pmic->slew_rate) + 2;
190 udelay(smps_delay);
191}
192
193/* vc_bypass_scale - VC bypass method of voltage scaling */
194int omap_vc_bypass_scale(struct voltagedomain *voltdm,
195 unsigned long target_volt)
196{
197 struct omap_vc_channel *vc = voltdm->vc;
198 u32 loop_cnt = 0, retries_cnt = 0;
199 u32 vc_valid, vc_bypass_val_reg, vc_bypass_value;
200 u8 target_vsel, current_vsel;
201 int ret;
202
203 ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, ¤t_vsel);
204 if (ret)
205 return ret;
206
207 vc_valid = vc->common->valid;
208 vc_bypass_val_reg = vc->common->bypass_val_reg;
209 vc_bypass_value = (target_vsel << vc->common->data_shift) |
210 (vc->volt_reg_addr << vc->common->regaddr_shift) |
211 (vc->i2c_slave_addr << vc->common->slaveaddr_shift);
212
213 voltdm->write(vc_bypass_value, vc_bypass_val_reg);
214 voltdm->write(vc_bypass_value | vc_valid, vc_bypass_val_reg);
215
216 vc_bypass_value = voltdm->read(vc_bypass_val_reg);
217 /*
218 * Loop till the bypass command is acknowledged from the SMPS.
219 * NOTE: This is legacy code. The loop count and retry count needs
220 * to be revisited.
221 */
222 while (!(vc_bypass_value & vc_valid)) {
223 loop_cnt++;
224
225 if (retries_cnt > 10) {
226 pr_warn("%s: Retry count exceeded\n", __func__);
227 return -ETIMEDOUT;
228 }
229
230 if (loop_cnt > 50) {
231 retries_cnt++;
232 loop_cnt = 0;
233 udelay(10);
234 }
235 vc_bypass_value = voltdm->read(vc_bypass_val_reg);
236 }
237
238 omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
239 return 0;
240}
241
242/* Convert microsecond value to number of 32kHz clock cycles */
243static inline u32 omap_usec_to_32k(u32 usec)
244{
245 return DIV_ROUND_UP_ULL(32768ULL * (u64)usec, 1000000ULL);
246}
247
248struct omap3_vc_timings {
249 u32 voltsetup1;
250 u32 voltsetup2;
251};
252
253struct omap3_vc {
254 struct voltagedomain *vd;
255 u32 voltctrl;
256 u32 voltsetup1;
257 u32 voltsetup2;
258 struct omap3_vc_timings timings[2];
259};
260static struct omap3_vc vc;
261
262void omap3_vc_set_pmic_signaling(int core_next_state)
263{
264 struct voltagedomain *vd = vc.vd;
265 struct omap3_vc_timings *c = vc.timings;
266 u32 voltctrl, voltsetup1, voltsetup2;
267
268 voltctrl = vc.voltctrl;
269 voltsetup1 = vc.voltsetup1;
270 voltsetup2 = vc.voltsetup2;
271
272 switch (core_next_state) {
273 case PWRDM_POWER_OFF:
274 voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_RET |
275 OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP);
276 voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_OFF;
277 if (voltctrl & OMAP3430_PRM_VOLTCTRL_SEL_OFF)
278 voltsetup2 = c->voltsetup2;
279 else
280 voltsetup1 = c->voltsetup1;
281 break;
282 case PWRDM_POWER_RET:
283 default:
284 c++;
285 voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_OFF |
286 OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP);
287 voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_RET;
288 voltsetup1 = c->voltsetup1;
289 break;
290 }
291
292 if (voltctrl != vc.voltctrl) {
293 vd->write(voltctrl, OMAP3_PRM_VOLTCTRL_OFFSET);
294 vc.voltctrl = voltctrl;
295 }
296 if (voltsetup1 != vc.voltsetup1) {
297 vd->write(c->voltsetup1,
298 OMAP3_PRM_VOLTSETUP1_OFFSET);
299 vc.voltsetup1 = voltsetup1;
300 }
301 if (voltsetup2 != vc.voltsetup2) {
302 vd->write(c->voltsetup2,
303 OMAP3_PRM_VOLTSETUP2_OFFSET);
304 vc.voltsetup2 = voltsetup2;
305 }
306}
307
308void omap4_vc_set_pmic_signaling(int core_next_state)
309{
310 struct voltagedomain *vd = vc.vd;
311 u32 val;
312
313 if (!vd)
314 return;
315
316 switch (core_next_state) {
317 case PWRDM_POWER_RET:
318 val = OMAP4_VDD_RET_VAL;
319 break;
320 default:
321 val = OMAP4_VDD_DEFAULT_VAL;
322 break;
323 }
324
325 vd->write(val, OMAP4_PRM_VOLTCTRL_OFFSET);
326}
327
328/*
329 * Configure signal polarity for sys_clkreq and sys_off_mode pins
330 * as the default values are wrong and can cause the system to hang
331 * if any twl4030 scripts are loaded.
332 */
333static void __init omap3_vc_init_pmic_signaling(struct voltagedomain *voltdm)
334{
335 u32 val;
336
337 if (vc.vd)
338 return;
339
340 vc.vd = voltdm;
341
342 val = voltdm->read(OMAP3_PRM_POLCTRL_OFFSET);
343 if (!(val & OMAP3430_PRM_POLCTRL_CLKREQ_POL) ||
344 (val & OMAP3430_PRM_POLCTRL_OFFMODE_POL)) {
345 val |= OMAP3430_PRM_POLCTRL_CLKREQ_POL;
346 val &= ~OMAP3430_PRM_POLCTRL_OFFMODE_POL;
347 pr_debug("PM: fixing sys_clkreq and sys_off_mode polarity to 0x%x\n",
348 val);
349 voltdm->write(val, OMAP3_PRM_POLCTRL_OFFSET);
350 }
351
352 /*
353 * By default let's use I2C4 signaling for retention idle
354 * and sys_off_mode pin signaling for off idle. This way we
355 * have sys_clk_req pin go down for retention and both
356 * sys_clk_req and sys_off_mode pins will go down for off
357 * idle. And we can also scale voltages to zero for off-idle.
358 * Note that no actual voltage scaling during off-idle will
359 * happen unless the board specific twl4030 PMIC scripts are
360 * loaded. See also omap_vc_i2c_init for comments regarding
361 * erratum i531.
362 */
363 val = voltdm->read(OMAP3_PRM_VOLTCTRL_OFFSET);
364 if (!(val & OMAP3430_PRM_VOLTCTRL_SEL_OFF)) {
365 val |= OMAP3430_PRM_VOLTCTRL_SEL_OFF;
366 pr_debug("PM: setting voltctrl sys_off_mode signaling to 0x%x\n",
367 val);
368 voltdm->write(val, OMAP3_PRM_VOLTCTRL_OFFSET);
369 }
370 vc.voltctrl = val;
371
372 omap3_vc_set_pmic_signaling(PWRDM_POWER_ON);
373}
374
375static void omap3_init_voltsetup1(struct voltagedomain *voltdm,
376 struct omap3_vc_timings *c, u32 idle)
377{
378 unsigned long val;
379
380 val = (voltdm->vc_param->on - idle) / voltdm->pmic->slew_rate;
381 val *= voltdm->sys_clk.rate / 8 / 1000000 + 1;
382 val <<= __ffs(voltdm->vfsm->voltsetup_mask);
383 c->voltsetup1 &= ~voltdm->vfsm->voltsetup_mask;
384 c->voltsetup1 |= val;
385}
386
387/**
388 * omap3_set_i2c_timings - sets i2c sleep timings for a channel
389 * @voltdm: channel to configure
390 * @off_mode: select whether retention or off mode values used
391 *
392 * Calculates and sets up voltage controller to use I2C based
393 * voltage scaling for sleep modes. This can be used for either off mode
394 * or retention. Off mode has additionally an option to use sys_off_mode
395 * pad, which uses a global signal to program the whole power IC to
396 * off-mode.
397 *
398 * Note that pmic is not controlling the voltage scaling during
399 * retention signaled over I2C4, so we can keep voltsetup2 as 0.
400 * And the oscillator is not shut off over I2C4, so no need to
401 * set clksetup.
402 */
403static void omap3_set_i2c_timings(struct voltagedomain *voltdm)
404{
405 struct omap3_vc_timings *c = vc.timings;
406
407 /* Configure PRWDM_POWER_OFF over I2C4 */
408 omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->off);
409 c++;
410 /* Configure PRWDM_POWER_RET over I2C4 */
411 omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->ret);
412}
413
414/**
415 * omap3_set_off_timings - sets off-mode timings for a channel
416 * @voltdm: channel to configure
417 *
418 * Calculates and sets up off-mode timings for a channel. Off-mode
419 * can use either I2C based voltage scaling, or alternatively
420 * sys_off_mode pad can be used to send a global command to power IC.n,
421 * sys_off_mode has the additional benefit that voltages can be
422 * scaled to zero volt level with TWL4030 / TWL5030, I2C can only
423 * scale to 600mV.
424 *
425 * Note that omap is not controlling the voltage scaling during
426 * off idle signaled by sys_off_mode, so we can keep voltsetup1
427 * as 0.
428 */
429static void omap3_set_off_timings(struct voltagedomain *voltdm)
430{
431 struct omap3_vc_timings *c = vc.timings;
432 u32 tstart, tshut, clksetup, voltoffset;
433
434 if (c->voltsetup2)
435 return;
436
437 omap_pm_get_oscillator(&tstart, &tshut);
438 if (tstart == ULONG_MAX) {
439 pr_debug("PM: oscillator start-up time not initialized, using 10ms\n");
440 clksetup = omap_usec_to_32k(10000);
441 } else {
442 clksetup = omap_usec_to_32k(tstart);
443 }
444
445 /*
446 * For twl4030 errata 27, we need to allow minimum ~488.32 us wait to
447 * switch from HFCLKIN to internal oscillator. That means timings
448 * have voltoffset fixed to 0xa in rounded up 32 KiHz cycles. And
449 * that means we can calculate the value based on the oscillator
450 * start-up time since voltoffset2 = clksetup - voltoffset.
451 */
452 voltoffset = omap_usec_to_32k(488);
453 c->voltsetup2 = clksetup - voltoffset;
454 voltdm->write(clksetup, OMAP3_PRM_CLKSETUP_OFFSET);
455 voltdm->write(voltoffset, OMAP3_PRM_VOLTOFFSET_OFFSET);
456}
457
458static void __init omap3_vc_init_channel(struct voltagedomain *voltdm)
459{
460 omap3_vc_init_pmic_signaling(voltdm);
461 omap3_set_off_timings(voltdm);
462 omap3_set_i2c_timings(voltdm);
463}
464
465/**
466 * omap4_calc_volt_ramp - calculates voltage ramping delays on omap4
467 * @voltdm: channel to calculate values for
468 * @voltage_diff: voltage difference in microvolts
469 *
470 * Calculates voltage ramp prescaler + counter values for a voltage
471 * difference on omap4. Returns a field value suitable for writing to
472 * VOLTSETUP register for a channel in following format:
473 * bits[8:9] prescaler ... bits[0:5] counter. See OMAP4 TRM for reference.
474 */
475static u32 omap4_calc_volt_ramp(struct voltagedomain *voltdm, u32 voltage_diff)
476{
477 u32 prescaler;
478 u32 cycles;
479 u32 time;
480
481 time = voltage_diff / voltdm->pmic->slew_rate;
482
483 cycles = voltdm->sys_clk.rate / 1000 * time / 1000;
484
485 cycles /= 64;
486 prescaler = 0;
487
488 /* shift to next prescaler until no overflow */
489
490 /* scale for div 256 = 64 * 4 */
491 if (cycles > 63) {
492 cycles /= 4;
493 prescaler++;
494 }
495
496 /* scale for div 512 = 256 * 2 */
497 if (cycles > 63) {
498 cycles /= 2;
499 prescaler++;
500 }
501
502 /* scale for div 2048 = 512 * 4 */
503 if (cycles > 63) {
504 cycles /= 4;
505 prescaler++;
506 }
507
508 /* check for overflow => invalid ramp time */
509 if (cycles > 63) {
510 pr_warn("%s: invalid setuptime for vdd_%s\n", __func__,
511 voltdm->name);
512 return 0;
513 }
514
515 cycles++;
516
517 return (prescaler << OMAP4430_RAMP_UP_PRESCAL_SHIFT) |
518 (cycles << OMAP4430_RAMP_UP_COUNT_SHIFT);
519}
520
521/**
522 * omap4_usec_to_val_scrm - convert microsecond value to SCRM module bitfield
523 * @usec: microseconds
524 * @shift: number of bits to shift left
525 * @mask: bitfield mask
526 *
527 * Converts microsecond value to OMAP4 SCRM bitfield. Bitfield is
528 * shifted to requested position, and checked agains the mask value.
529 * If larger, forced to the max value of the field (i.e. the mask itself.)
530 * Returns the SCRM bitfield value.
531 */
532static u32 omap4_usec_to_val_scrm(u32 usec, int shift, u32 mask)
533{
534 u32 val;
535
536 val = omap_usec_to_32k(usec) << shift;
537
538 /* Check for overflow, if yes, force to max value */
539 if (val > mask)
540 val = mask;
541
542 return val;
543}
544
545/**
546 * omap4_set_timings - set voltage ramp timings for a channel
547 * @voltdm: channel to configure
548 * @off_mode: whether off-mode values are used
549 *
550 * Calculates and sets the voltage ramp up / down values for a channel.
551 */
552static void omap4_set_timings(struct voltagedomain *voltdm, bool off_mode)
553{
554 u32 val;
555 u32 ramp;
556 int offset;
557 u32 tstart, tshut;
558
559 if (off_mode) {
560 ramp = omap4_calc_volt_ramp(voltdm,
561 voltdm->vc_param->on - voltdm->vc_param->off);
562 offset = voltdm->vfsm->voltsetup_off_reg;
563 } else {
564 ramp = omap4_calc_volt_ramp(voltdm,
565 voltdm->vc_param->on - voltdm->vc_param->ret);
566 offset = voltdm->vfsm->voltsetup_reg;
567 }
568
569 if (!ramp)
570 return;
571
572 val = voltdm->read(offset);
573
574 val |= ramp << OMAP4430_RAMP_DOWN_COUNT_SHIFT;
575
576 val |= ramp << OMAP4430_RAMP_UP_COUNT_SHIFT;
577
578 voltdm->write(val, offset);
579
580 omap_pm_get_oscillator(&tstart, &tshut);
581
582 val = omap4_usec_to_val_scrm(tstart, OMAP4_SETUPTIME_SHIFT,
583 OMAP4_SETUPTIME_MASK);
584 val |= omap4_usec_to_val_scrm(tshut, OMAP4_DOWNTIME_SHIFT,
585 OMAP4_DOWNTIME_MASK);
586
587 writel_relaxed(val, OMAP4_SCRM_CLKSETUPTIME);
588}
589
590static void __init omap4_vc_init_pmic_signaling(struct voltagedomain *voltdm)
591{
592 if (vc.vd)
593 return;
594
595 vc.vd = voltdm;
596 voltdm->write(OMAP4_VDD_DEFAULT_VAL, OMAP4_PRM_VOLTCTRL_OFFSET);
597}
598
599/* OMAP4 specific voltage init functions */
600static void __init omap4_vc_init_channel(struct voltagedomain *voltdm)
601{
602 omap4_vc_init_pmic_signaling(voltdm);
603 omap4_set_timings(voltdm, true);
604 omap4_set_timings(voltdm, false);
605}
606
607struct i2c_init_data {
608 u8 loadbits;
609 u8 load;
610 u8 hsscll_38_4;
611 u8 hsscll_26;
612 u8 hsscll_19_2;
613 u8 hsscll_16_8;
614 u8 hsscll_12;
615};
616
617static const struct i2c_init_data omap4_i2c_timing_data[] __initconst = {
618 {
619 .load = 50,
620 .loadbits = 0x3,
621 .hsscll_38_4 = 13,
622 .hsscll_26 = 11,
623 .hsscll_19_2 = 9,
624 .hsscll_16_8 = 9,
625 .hsscll_12 = 8,
626 },
627 {
628 .load = 25,
629 .loadbits = 0x2,
630 .hsscll_38_4 = 13,
631 .hsscll_26 = 11,
632 .hsscll_19_2 = 9,
633 .hsscll_16_8 = 9,
634 .hsscll_12 = 8,
635 },
636 {
637 .load = 12,
638 .loadbits = 0x1,
639 .hsscll_38_4 = 11,
640 .hsscll_26 = 10,
641 .hsscll_19_2 = 9,
642 .hsscll_16_8 = 9,
643 .hsscll_12 = 8,
644 },
645 {
646 .load = 0,
647 .loadbits = 0x0,
648 .hsscll_38_4 = 12,
649 .hsscll_26 = 10,
650 .hsscll_19_2 = 9,
651 .hsscll_16_8 = 8,
652 .hsscll_12 = 8,
653 },
654};
655
656/**
657 * omap4_vc_i2c_timing_init - sets up board I2C timing parameters
658 * @voltdm: voltagedomain pointer to get data from
659 *
660 * Use PMIC + board supplied settings for calculating the total I2C
661 * channel capacitance and set the timing parameters based on this.
662 * Pre-calculated values are provided in data tables, as it is not
663 * too straightforward to calculate these runtime.
664 */
665static void __init omap4_vc_i2c_timing_init(struct voltagedomain *voltdm)
666{
667 u32 capacitance;
668 u32 val;
669 u16 hsscll;
670 const struct i2c_init_data *i2c_data;
671
672 if (!voltdm->pmic->i2c_high_speed) {
673 pr_info("%s: using bootloader low-speed timings\n", __func__);
674 return;
675 }
676
677 /* PCB trace capacitance, 0.125pF / mm => mm / 8 */
678 capacitance = DIV_ROUND_UP(sr_i2c_pcb_length, 8);
679
680 /* OMAP pad capacitance */
681 capacitance += 4;
682
683 /* PMIC pad capacitance */
684 capacitance += voltdm->pmic->i2c_pad_load;
685
686 /* Search for capacitance match in the table */
687 i2c_data = omap4_i2c_timing_data;
688
689 while (i2c_data->load > capacitance)
690 i2c_data++;
691
692 /* Select proper values based on sysclk frequency */
693 switch (voltdm->sys_clk.rate) {
694 case 38400000:
695 hsscll = i2c_data->hsscll_38_4;
696 break;
697 case 26000000:
698 hsscll = i2c_data->hsscll_26;
699 break;
700 case 19200000:
701 hsscll = i2c_data->hsscll_19_2;
702 break;
703 case 16800000:
704 hsscll = i2c_data->hsscll_16_8;
705 break;
706 case 12000000:
707 hsscll = i2c_data->hsscll_12;
708 break;
709 default:
710 pr_warn("%s: unsupported sysclk rate: %d!\n", __func__,
711 voltdm->sys_clk.rate);
712 return;
713 }
714
715 /* Loadbits define pull setup for the I2C channels */
716 val = i2c_data->loadbits << 25 | i2c_data->loadbits << 29;
717
718 /* Write to SYSCTRL_PADCONF_WKUP_CTRL_I2C_2 to setup I2C pull */
719 writel_relaxed(val, OMAP2_L4_IO_ADDRESS(OMAP4_CTRL_MODULE_PAD_WKUP +
720 OMAP4_CTRL_MODULE_PAD_WKUP_CONTROL_I2C_2));
721
722 /* HSSCLH can always be zero */
723 val = hsscll << OMAP4430_HSSCLL_SHIFT;
724 val |= (0x28 << OMAP4430_SCLL_SHIFT | 0x2c << OMAP4430_SCLH_SHIFT);
725
726 /* Write setup times to I2C config register */
727 voltdm->write(val, OMAP4_PRM_VC_CFG_I2C_CLK_OFFSET);
728}
729
730
731
732/**
733 * omap_vc_i2c_init - initialize I2C interface to PMIC
734 * @voltdm: voltage domain containing VC data
735 *
736 * Use PMIC supplied settings for I2C high-speed mode and
737 * master code (if set) and program the VC I2C configuration
738 * register.
739 *
740 * The VC I2C configuration is common to all VC channels,
741 * so this function only configures I2C for the first VC
742 * channel registers. All other VC channels will use the
743 * same configuration.
744 */
745static void __init omap_vc_i2c_init(struct voltagedomain *voltdm)
746{
747 struct omap_vc_channel *vc = voltdm->vc;
748 static bool initialized;
749 static bool i2c_high_speed;
750 u8 mcode;
751
752 if (initialized) {
753 if (voltdm->pmic->i2c_high_speed != i2c_high_speed)
754 pr_warn("%s: I2C config for vdd_%s does not match other channels (%u).\n",
755 __func__, voltdm->name, i2c_high_speed);
756 return;
757 }
758
759 /*
760 * Note that for omap3 OMAP3430_SREN_MASK clears SREN to work around
761 * erratum i531 "Extra Power Consumed When Repeated Start Operation
762 * Mode Is Enabled on I2C Interface Dedicated for Smart Reflex (I2C4)".
763 * Otherwise I2C4 eventually leads into about 23mW extra power being
764 * consumed even during off idle using VMODE.
765 */
766 i2c_high_speed = voltdm->pmic->i2c_high_speed;
767 if (i2c_high_speed)
768 voltdm->rmw(vc->common->i2c_cfg_clear_mask,
769 vc->common->i2c_cfg_hsen_mask,
770 vc->common->i2c_cfg_reg);
771
772 mcode = voltdm->pmic->i2c_mcode;
773 if (mcode)
774 voltdm->rmw(vc->common->i2c_mcode_mask,
775 mcode << __ffs(vc->common->i2c_mcode_mask),
776 vc->common->i2c_cfg_reg);
777
778 if (cpu_is_omap44xx())
779 omap4_vc_i2c_timing_init(voltdm);
780
781 initialized = true;
782}
783
784/**
785 * omap_vc_calc_vsel - calculate vsel value for a channel
786 * @voltdm: channel to calculate value for
787 * @uvolt: microvolt value to convert to vsel
788 *
789 * Converts a microvolt value to vsel value for the used PMIC.
790 * This checks whether the microvolt value is out of bounds, and
791 * adjusts the value accordingly. If unsupported value detected,
792 * warning is thrown.
793 */
794static u8 omap_vc_calc_vsel(struct voltagedomain *voltdm, u32 uvolt)
795{
796 if (voltdm->pmic->vddmin > uvolt)
797 uvolt = voltdm->pmic->vddmin;
798 if (voltdm->pmic->vddmax < uvolt) {
799 WARN(1, "%s: voltage not supported by pmic: %u vs max %u\n",
800 __func__, uvolt, voltdm->pmic->vddmax);
801 /* Lets try maximum value anyway */
802 uvolt = voltdm->pmic->vddmax;
803 }
804
805 return voltdm->pmic->uv_to_vsel(uvolt);
806}
807
808#ifdef CONFIG_PM
809/**
810 * omap_pm_setup_sr_i2c_pcb_length - set length of SR I2C traces on PCB
811 * @mm: length of the PCB trace in millimetres
812 *
813 * Sets the PCB trace length for the I2C channel. By default uses 63mm.
814 * This is needed for properly calculating the capacitance value for
815 * the PCB trace, and for setting the SR I2C channel timing parameters.
816 */
817void __init omap_pm_setup_sr_i2c_pcb_length(u32 mm)
818{
819 sr_i2c_pcb_length = mm;
820}
821#endif
822
823void __init omap_vc_init_channel(struct voltagedomain *voltdm)
824{
825 struct omap_vc_channel *vc = voltdm->vc;
826 u8 on_vsel, onlp_vsel, ret_vsel, off_vsel;
827 u32 val;
828
829 if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
830 pr_err("%s: No PMIC info for vdd_%s\n", __func__, voltdm->name);
831 return;
832 }
833
834 if (!voltdm->read || !voltdm->write) {
835 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
836 __func__, voltdm->name);
837 return;
838 }
839
840 vc->cfg_channel = 0;
841 if (vc->flags & OMAP_VC_CHANNEL_CFG_MUTANT)
842 vc_cfg_bits = &vc_mutant_channel_cfg;
843 else
844 vc_cfg_bits = &vc_default_channel_cfg;
845
846 /* get PMIC/board specific settings */
847 vc->i2c_slave_addr = voltdm->pmic->i2c_slave_addr;
848 vc->volt_reg_addr = voltdm->pmic->volt_reg_addr;
849 vc->cmd_reg_addr = voltdm->pmic->cmd_reg_addr;
850
851 /* Configure the i2c slave address for this VC */
852 voltdm->rmw(vc->smps_sa_mask,
853 vc->i2c_slave_addr << __ffs(vc->smps_sa_mask),
854 vc->smps_sa_reg);
855 vc->cfg_channel |= vc_cfg_bits->sa;
856
857 /*
858 * Configure the PMIC register addresses.
859 */
860 voltdm->rmw(vc->smps_volra_mask,
861 vc->volt_reg_addr << __ffs(vc->smps_volra_mask),
862 vc->smps_volra_reg);
863 vc->cfg_channel |= vc_cfg_bits->rav;
864
865 if (vc->cmd_reg_addr) {
866 voltdm->rmw(vc->smps_cmdra_mask,
867 vc->cmd_reg_addr << __ffs(vc->smps_cmdra_mask),
868 vc->smps_cmdra_reg);
869 vc->cfg_channel |= vc_cfg_bits->rac;
870 }
871
872 if (vc->cmd_reg_addr == vc->volt_reg_addr)
873 vc->cfg_channel |= vc_cfg_bits->racen;
874
875 /* Set up the on, inactive, retention and off voltage */
876 on_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->on);
877 onlp_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->onlp);
878 ret_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->ret);
879 off_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->off);
880
881 val = ((on_vsel << vc->common->cmd_on_shift) |
882 (onlp_vsel << vc->common->cmd_onlp_shift) |
883 (ret_vsel << vc->common->cmd_ret_shift) |
884 (off_vsel << vc->common->cmd_off_shift));
885 voltdm->write(val, vc->cmdval_reg);
886 vc->cfg_channel |= vc_cfg_bits->cmd;
887
888 /* Channel configuration */
889 omap_vc_config_channel(voltdm);
890
891 omap_vc_i2c_init(voltdm);
892
893 if (cpu_is_omap34xx())
894 omap3_vc_init_channel(voltdm);
895 else if (cpu_is_omap44xx())
896 omap4_vc_init_channel(voltdm);
897}
898