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dpll3xxx.c

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linux-6.19.14/drivers/clk/ti/dpll3xxx.c C
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * OMAP3/4 - specific DPLL control functions
   4 *
   5 * Copyright (C) 2009-2010 Texas Instruments, Inc.
   6 * Copyright (C) 2009-2010 Nokia Corporation
   7 *
   8 * Written by Paul Walmsley
   9 * Testing and integration fixes by Jouni Högander
  10 *
  11 * 36xx support added by Vishwanath BS, Richard Woodruff, and Nishanth
  12 * Menon
  13 *
  14 * Parts of this code are based on code written by
  15 * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
  16 */
  17
  18#include <linux/kernel.h>
  19#include <linux/device.h>
  20#include <linux/list.h>
  21#include <linux/errno.h>
  22#include <linux/delay.h>
  23#include <linux/clk.h>
  24#include <linux/io.h>
  25#include <linux/bitops.h>
  26#include <linux/clkdev.h>
  27#include <linux/clk/ti.h>
  28
  29#include "clock.h"
  30
  31/* CM_AUTOIDLE_PLL*.AUTO_* bit values */
  32#define DPLL_AUTOIDLE_DISABLE			0x0
  33#define DPLL_AUTOIDLE_LOW_POWER_STOP		0x1
  34
  35#define MAX_DPLL_WAIT_TRIES		1000000
  36
  37#define OMAP3XXX_EN_DPLL_LOCKED		0x7
  38
  39/* Forward declarations */
  40static u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk);
  41static void omap3_dpll_deny_idle(struct clk_hw_omap *clk);
  42static void omap3_dpll_allow_idle(struct clk_hw_omap *clk);
  43
  44/* Private functions */
  45
  46/* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */
  47static void _omap3_dpll_write_clken(struct clk_hw_omap *clk, u8 clken_bits)
  48{
  49	const struct dpll_data *dd;
  50	u32 v;
  51
  52	dd = clk->dpll_data;
  53
  54	v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
  55	v &= ~dd->enable_mask;
  56	v |= clken_bits << __ffs(dd->enable_mask);
  57	ti_clk_ll_ops->clk_writel(v, &dd->control_reg);
  58}
  59
  60/* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */
  61static int _omap3_wait_dpll_status(struct clk_hw_omap *clk, u8 state)
  62{
  63	const struct dpll_data *dd;
  64	int i = 0;
  65	int ret = -EINVAL;
  66	const char *clk_name;
  67
  68	dd = clk->dpll_data;
  69	clk_name = clk_hw_get_name(&clk->hw);
  70
  71	state <<= __ffs(dd->idlest_mask);
  72
  73	while (((ti_clk_ll_ops->clk_readl(&dd->idlest_reg) & dd->idlest_mask)
  74		!= state) && i < MAX_DPLL_WAIT_TRIES) {
  75		i++;
  76		udelay(1);
  77	}
  78
  79	if (i == MAX_DPLL_WAIT_TRIES) {
  80		pr_err("clock: %s failed transition to '%s'\n",
  81		       clk_name, (state) ? "locked" : "bypassed");
  82	} else {
  83		pr_debug("clock: %s transition to '%s' in %d loops\n",
  84			 clk_name, (state) ? "locked" : "bypassed", i);
  85
  86		ret = 0;
  87	}
  88
  89	return ret;
  90}
  91
  92/* From 3430 TRM ES2 4.7.6.2 */
  93static u16 _omap3_dpll_compute_freqsel(struct clk_hw_omap *clk, u8 n)
  94{
  95	unsigned long fint;
  96	u16 f = 0;
  97
  98	fint = clk_hw_get_rate(clk->dpll_data->clk_ref) / n;
  99
 100	pr_debug("clock: fint is %lu\n", fint);
 101
 102	if (fint >= 750000 && fint <= 1000000)
 103		f = 0x3;
 104	else if (fint > 1000000 && fint <= 1250000)
 105		f = 0x4;
 106	else if (fint > 1250000 && fint <= 1500000)
 107		f = 0x5;
 108	else if (fint > 1500000 && fint <= 1750000)
 109		f = 0x6;
 110	else if (fint > 1750000 && fint <= 2100000)
 111		f = 0x7;
 112	else if (fint > 7500000 && fint <= 10000000)
 113		f = 0xB;
 114	else if (fint > 10000000 && fint <= 12500000)
 115		f = 0xC;
 116	else if (fint > 12500000 && fint <= 15000000)
 117		f = 0xD;
 118	else if (fint > 15000000 && fint <= 17500000)
 119		f = 0xE;
 120	else if (fint > 17500000 && fint <= 21000000)
 121		f = 0xF;
 122	else
 123		pr_debug("clock: unknown freqsel setting for %d\n", n);
 124
 125	return f;
 126}
 127
 128/**
 129 * _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness
 130 * @clk: pointer to a DPLL struct clk
 131 *
 132 * Instructs a non-CORE DPLL to lock.  Waits for the DPLL to report
 133 * readiness before returning.  Will save and restore the DPLL's
 134 * autoidle state across the enable, per the CDP code.  If the DPLL
 135 * locked successfully, return 0; if the DPLL did not lock in the time
 136 * allotted, or DPLL3 was passed in, return -EINVAL.
 137 */
 138static int _omap3_noncore_dpll_lock(struct clk_hw_omap *clk)
 139{
 140	const struct dpll_data *dd;
 141	u8 ai;
 142	u8 state = 1;
 143	int r = 0;
 144
 145	pr_debug("clock: locking DPLL %s\n", clk_hw_get_name(&clk->hw));
 146
 147	dd = clk->dpll_data;
 148	state <<= __ffs(dd->idlest_mask);
 149
 150	/* Check if already locked */
 151	if ((ti_clk_ll_ops->clk_readl(&dd->idlest_reg) & dd->idlest_mask) ==
 152	    state)
 153		goto done;
 154
 155	ai = omap3_dpll_autoidle_read(clk);
 156
 157	if (ai)
 158		omap3_dpll_deny_idle(clk);
 159
 160	_omap3_dpll_write_clken(clk, DPLL_LOCKED);
 161
 162	r = _omap3_wait_dpll_status(clk, 1);
 163
 164	if (ai)
 165		omap3_dpll_allow_idle(clk);
 166
 167done:
 168	return r;
 169}
 170
 171/**
 172 * _omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness
 173 * @clk: pointer to a DPLL struct clk
 174 *
 175 * Instructs a non-CORE DPLL to enter low-power bypass mode.  In
 176 * bypass mode, the DPLL's rate is set equal to its parent clock's
 177 * rate.  Waits for the DPLL to report readiness before returning.
 178 * Will save and restore the DPLL's autoidle state across the enable,
 179 * per the CDP code.  If the DPLL entered bypass mode successfully,
 180 * return 0; if the DPLL did not enter bypass in the time allotted, or
 181 * DPLL3 was passed in, or the DPLL does not support low-power bypass,
 182 * return -EINVAL.
 183 */
 184static int _omap3_noncore_dpll_bypass(struct clk_hw_omap *clk)
 185{
 186	int r;
 187	u8 ai;
 188
 189	if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS)))
 190		return -EINVAL;
 191
 192	pr_debug("clock: configuring DPLL %s for low-power bypass\n",
 193		 clk_hw_get_name(&clk->hw));
 194
 195	ai = omap3_dpll_autoidle_read(clk);
 196
 197	_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS);
 198
 199	r = _omap3_wait_dpll_status(clk, 0);
 200
 201	if (ai)
 202		omap3_dpll_allow_idle(clk);
 203
 204	return r;
 205}
 206
 207/**
 208 * _omap3_noncore_dpll_stop - instruct a DPLL to stop
 209 * @clk: pointer to a DPLL struct clk
 210 *
 211 * Instructs a non-CORE DPLL to enter low-power stop. Will save and
 212 * restore the DPLL's autoidle state across the stop, per the CDP
 213 * code.  If DPLL3 was passed in, or the DPLL does not support
 214 * low-power stop, return -EINVAL; otherwise, return 0.
 215 */
 216static int _omap3_noncore_dpll_stop(struct clk_hw_omap *clk)
 217{
 218	u8 ai;
 219
 220	if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP)))
 221		return -EINVAL;
 222
 223	pr_debug("clock: stopping DPLL %s\n", clk_hw_get_name(&clk->hw));
 224
 225	ai = omap3_dpll_autoidle_read(clk);
 226
 227	_omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP);
 228
 229	if (ai)
 230		omap3_dpll_allow_idle(clk);
 231
 232	return 0;
 233}
 234
 235/**
 236 * _lookup_dco - Lookup DCO used by j-type DPLL
 237 * @clk: pointer to a DPLL struct clk
 238 * @dco: digital control oscillator selector
 239 * @m: DPLL multiplier to set
 240 * @n: DPLL divider to set
 241 *
 242 * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
 243 *
 244 * XXX This code is not needed for 3430/AM35xx; can it be optimized
 245 * out in non-multi-OMAP builds for those chips?
 246 */
 247static void _lookup_dco(struct clk_hw_omap *clk, u8 *dco, u16 m, u8 n)
 248{
 249	unsigned long fint, clkinp; /* watch out for overflow */
 250
 251	clkinp = clk_hw_get_rate(clk_hw_get_parent(&clk->hw));
 252	fint = (clkinp / n) * m;
 253
 254	if (fint < 1000000000)
 255		*dco = 2;
 256	else
 257		*dco = 4;
 258}
 259
 260/**
 261 * _lookup_sddiv - Calculate sigma delta divider for j-type DPLL
 262 * @clk: pointer to a DPLL struct clk
 263 * @sd_div: target sigma-delta divider
 264 * @m: DPLL multiplier to set
 265 * @n: DPLL divider to set
 266 *
 267 * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)"
 268 *
 269 * XXX This code is not needed for 3430/AM35xx; can it be optimized
 270 * out in non-multi-OMAP builds for those chips?
 271 */
 272static void _lookup_sddiv(struct clk_hw_omap *clk, u8 *sd_div, u16 m, u8 n)
 273{
 274	unsigned long clkinp, sd; /* watch out for overflow */
 275	int mod1, mod2;
 276
 277	clkinp = clk_hw_get_rate(clk_hw_get_parent(&clk->hw));
 278
 279	/*
 280	 * target sigma-delta to near 250MHz
 281	 * sd = ceil[(m/(n+1)) * (clkinp_MHz / 250)]
 282	 */
 283	clkinp /= 100000; /* shift from MHz to 10*Hz for 38.4 and 19.2 */
 284	mod1 = (clkinp * m) % (250 * n);
 285	sd = (clkinp * m) / (250 * n);
 286	mod2 = sd % 10;
 287	sd /= 10;
 288
 289	if (mod1 || mod2)
 290		sd++;
 291	*sd_div = sd;
 292}
 293
 294/**
 295 * omap3_noncore_dpll_ssc_program - set spread-spectrum clocking registers
 296 * @clk:	struct clk * of DPLL to set
 297 *
 298 * Enable the DPLL spread spectrum clocking if frequency modulation and
 299 * frequency spreading have been set, otherwise disable it.
 300 */
 301static void omap3_noncore_dpll_ssc_program(struct clk_hw_omap *clk)
 302{
 303	struct dpll_data *dd = clk->dpll_data;
 304	unsigned long ref_rate;
 305	u32 v, ctrl, mod_freq_divider, exponent, mantissa;
 306	u32 deltam_step, deltam_ceil;
 307
 308	ctrl = ti_clk_ll_ops->clk_readl(&dd->control_reg);
 309
 310	if (dd->ssc_modfreq && dd->ssc_deltam) {
 311		ctrl |= dd->ssc_enable_mask;
 312
 313		if (dd->ssc_downspread)
 314			ctrl |= dd->ssc_downspread_mask;
 315		else
 316			ctrl &= ~dd->ssc_downspread_mask;
 317
 318		ref_rate = clk_hw_get_rate(dd->clk_ref);
 319		mod_freq_divider =
 320		    (ref_rate / dd->last_rounded_n) / (4 * dd->ssc_modfreq);
 321		if (dd->ssc_modfreq > (ref_rate / 70))
 322			pr_warn("clock: SSC modulation frequency of DPLL %s greater than %ld\n",
 323				__clk_get_name(clk->hw.clk), ref_rate / 70);
 324
 325		exponent = 0;
 326		mantissa = mod_freq_divider;
 327		while ((mantissa > 127) && (exponent < 7)) {
 328			exponent++;
 329			mantissa /= 2;
 330		}
 331		if (mantissa > 127)
 332			mantissa = 127;
 333
 334		v = ti_clk_ll_ops->clk_readl(&dd->ssc_modfreq_reg);
 335		v &= ~(dd->ssc_modfreq_mant_mask | dd->ssc_modfreq_exp_mask);
 336		v |= mantissa << __ffs(dd->ssc_modfreq_mant_mask);
 337		v |= exponent << __ffs(dd->ssc_modfreq_exp_mask);
 338		ti_clk_ll_ops->clk_writel(v, &dd->ssc_modfreq_reg);
 339
 340		deltam_step = dd->last_rounded_m * dd->ssc_deltam;
 341		deltam_step /= 10;
 342		if (dd->ssc_downspread)
 343			deltam_step /= 2;
 344
 345		deltam_step <<= __ffs(dd->ssc_deltam_int_mask);
 346		deltam_step /= 100;
 347		deltam_step /= mod_freq_divider;
 348		if (deltam_step > 0xFFFFF)
 349			deltam_step = 0xFFFFF;
 350
 351		deltam_ceil = (deltam_step & dd->ssc_deltam_int_mask) >>
 352		    __ffs(dd->ssc_deltam_int_mask);
 353		if (deltam_step & dd->ssc_deltam_frac_mask)
 354			deltam_ceil++;
 355
 356		if ((dd->ssc_downspread &&
 357		     ((dd->last_rounded_m - (2 * deltam_ceil)) < 20 ||
 358		      dd->last_rounded_m > 2045)) ||
 359		    ((dd->last_rounded_m - deltam_ceil) < 20 ||
 360		     (dd->last_rounded_m + deltam_ceil) > 2045))
 361			pr_warn("clock: SSC multiplier of DPLL %s is out of range\n",
 362				__clk_get_name(clk->hw.clk));
 363
 364		v = ti_clk_ll_ops->clk_readl(&dd->ssc_deltam_reg);
 365		v &= ~(dd->ssc_deltam_int_mask | dd->ssc_deltam_frac_mask);
 366		v |= deltam_step << __ffs(dd->ssc_deltam_int_mask |
 367					  dd->ssc_deltam_frac_mask);
 368		ti_clk_ll_ops->clk_writel(v, &dd->ssc_deltam_reg);
 369	} else {
 370		ctrl &= ~dd->ssc_enable_mask;
 371	}
 372
 373	ti_clk_ll_ops->clk_writel(ctrl, &dd->control_reg);
 374}
 375
 376/**
 377 * omap3_noncore_dpll_program - set non-core DPLL M,N values directly
 378 * @clk:	struct clk * of DPLL to set
 379 * @freqsel:	FREQSEL value to set
 380 *
 381 * Program the DPLL with the last M, N values calculated, and wait for
 382 * the DPLL to lock. Returns -EINVAL upon error, or 0 upon success.
 383 */
 384static int omap3_noncore_dpll_program(struct clk_hw_omap *clk, u16 freqsel)
 385{
 386	struct dpll_data *dd = clk->dpll_data;
 387	u8 dco, sd_div, ai = 0;
 388	u32 v;
 389	bool errata_i810;
 390
 391	/* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */
 392	_omap3_noncore_dpll_bypass(clk);
 393
 394	/*
 395	 * Set jitter correction. Jitter correction applicable for OMAP343X
 396	 * only since freqsel field is no longer present on other devices.
 397	 */
 398	if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
 399		v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
 400		v &= ~dd->freqsel_mask;
 401		v |= freqsel << __ffs(dd->freqsel_mask);
 402		ti_clk_ll_ops->clk_writel(v, &dd->control_reg);
 403	}
 404
 405	/* Set DPLL multiplier, divider */
 406	v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
 407
 408	/* Handle Duty Cycle Correction */
 409	if (dd->dcc_mask) {
 410		if (dd->last_rounded_rate >= dd->dcc_rate)
 411			v |= dd->dcc_mask; /* Enable DCC */
 412		else
 413			v &= ~dd->dcc_mask; /* Disable DCC */
 414	}
 415
 416	v &= ~(dd->mult_mask | dd->div1_mask);
 417	v |= dd->last_rounded_m << __ffs(dd->mult_mask);
 418	v |= (dd->last_rounded_n - 1) << __ffs(dd->div1_mask);
 419
 420	/* Configure dco and sd_div for dplls that have these fields */
 421	if (dd->dco_mask) {
 422		_lookup_dco(clk, &dco, dd->last_rounded_m, dd->last_rounded_n);
 423		v &= ~(dd->dco_mask);
 424		v |= dco << __ffs(dd->dco_mask);
 425	}
 426	if (dd->sddiv_mask) {
 427		_lookup_sddiv(clk, &sd_div, dd->last_rounded_m,
 428			      dd->last_rounded_n);
 429		v &= ~(dd->sddiv_mask);
 430		v |= sd_div << __ffs(dd->sddiv_mask);
 431	}
 432
 433	/*
 434	 * Errata i810 - DPLL controller can get stuck while transitioning
 435	 * to a power saving state. Software must ensure the DPLL can not
 436	 * transition to a low power state while changing M/N values.
 437	 * Easiest way to accomplish this is to prevent DPLL autoidle
 438	 * before doing the M/N re-program.
 439	 */
 440	errata_i810 = ti_clk_get_features()->flags & TI_CLK_ERRATA_I810;
 441
 442	if (errata_i810) {
 443		ai = omap3_dpll_autoidle_read(clk);
 444		if (ai) {
 445			omap3_dpll_deny_idle(clk);
 446
 447			/* OCP barrier */
 448			omap3_dpll_autoidle_read(clk);
 449		}
 450	}
 451
 452	ti_clk_ll_ops->clk_writel(v, &dd->mult_div1_reg);
 453
 454	/* Set 4X multiplier and low-power mode */
 455	if (dd->m4xen_mask || dd->lpmode_mask) {
 456		v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
 457
 458		if (dd->m4xen_mask) {
 459			if (dd->last_rounded_m4xen)
 460				v |= dd->m4xen_mask;
 461			else
 462				v &= ~dd->m4xen_mask;
 463		}
 464
 465		if (dd->lpmode_mask) {
 466			if (dd->last_rounded_lpmode)
 467				v |= dd->lpmode_mask;
 468			else
 469				v &= ~dd->lpmode_mask;
 470		}
 471
 472		ti_clk_ll_ops->clk_writel(v, &dd->control_reg);
 473	}
 474
 475	if (dd->ssc_enable_mask)
 476		omap3_noncore_dpll_ssc_program(clk);
 477
 478	/* We let the clock framework set the other output dividers later */
 479
 480	/* REVISIT: Set ramp-up delay? */
 481
 482	_omap3_noncore_dpll_lock(clk);
 483
 484	if (errata_i810 && ai)
 485		omap3_dpll_allow_idle(clk);
 486
 487	return 0;
 488}
 489
 490/* Public functions */
 491
 492/**
 493 * omap3_dpll_recalc - recalculate DPLL rate
 494 * @hw: struct clk_hw containing the DPLL struct clk
 495 * @parent_rate: clock rate of the DPLL parent
 496 *
 497 * Recalculate and propagate the DPLL rate.
 498 */
 499unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate)
 500{
 501	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 502
 503	return omap2_get_dpll_rate(clk);
 504}
 505
 506/* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */
 507
 508/**
 509 * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
 510 * @hw: struct clk_hw containing then pointer to a DPLL struct clk
 511 *
 512 * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
 513 * The choice of modes depends on the DPLL's programmed rate: if it is
 514 * the same as the DPLL's parent clock, it will enter bypass;
 515 * otherwise, it will enter lock.  This code will wait for the DPLL to
 516 * indicate readiness before returning, unless the DPLL takes too long
 517 * to enter the target state.  Intended to be used as the struct clk's
 518 * enable function.  If DPLL3 was passed in, or the DPLL does not
 519 * support low-power stop, or if the DPLL took too long to enter
 520 * bypass or lock, return -EINVAL; otherwise, return 0.
 521 */
 522int omap3_noncore_dpll_enable(struct clk_hw *hw)
 523{
 524	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 525	int r;
 526	struct dpll_data *dd;
 527	struct clk_hw *parent;
 528
 529	dd = clk->dpll_data;
 530	if (!dd)
 531		return -EINVAL;
 532
 533	if (clk->clkdm) {
 534		r = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk);
 535		if (r) {
 536			WARN(1,
 537			     "%s: could not enable %s's clockdomain %s: %d\n",
 538			     __func__, clk_hw_get_name(hw),
 539			     clk->clkdm_name, r);
 540			return r;
 541		}
 542	}
 543
 544	parent = clk_hw_get_parent(hw);
 545
 546	if (clk_hw_get_rate(hw) == clk_hw_get_rate(dd->clk_bypass)) {
 547		WARN_ON(parent != dd->clk_bypass);
 548		r = _omap3_noncore_dpll_bypass(clk);
 549	} else {
 550		WARN_ON(parent != dd->clk_ref);
 551		r = _omap3_noncore_dpll_lock(clk);
 552	}
 553
 554	return r;
 555}
 556
 557/**
 558 * omap3_noncore_dpll_disable - instruct a DPLL to enter low-power stop
 559 * @hw: struct clk_hw containing then pointer to a DPLL struct clk
 560 *
 561 * Instructs a non-CORE DPLL to enter low-power stop.  This function is
 562 * intended for use in struct clkops.  No return value.
 563 */
 564void omap3_noncore_dpll_disable(struct clk_hw *hw)
 565{
 566	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 567
 568	_omap3_noncore_dpll_stop(clk);
 569	if (clk->clkdm)
 570		ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
 571}
 572
 573/* Non-CORE DPLL rate set code */
 574
 575/**
 576 * omap3_noncore_dpll_determine_rate - determine rate for a DPLL
 577 * @hw: pointer to the clock to determine rate for
 578 * @req: target rate request
 579 *
 580 * Determines which DPLL mode to use for reaching a desired target rate.
 581 * Checks whether the DPLL shall be in bypass or locked mode, and if
 582 * locked, calculates the M,N values for the DPLL via round-rate.
 583 * Returns a 0 on success, negative error value in failure.
 584 */
 585int omap3_noncore_dpll_determine_rate(struct clk_hw *hw,
 586				      struct clk_rate_request *req)
 587{
 588	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 589	struct dpll_data *dd;
 590	int ret;
 591
 592	if (!req->rate)
 593		return -EINVAL;
 594
 595	dd = clk->dpll_data;
 596	if (!dd)
 597		return -EINVAL;
 598
 599	if (clk_hw_get_rate(dd->clk_bypass) == req->rate &&
 600	    (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
 601		req->best_parent_hw = dd->clk_bypass;
 602	} else {
 603		ret = omap2_dpll_determine_rate(hw, req);
 604		if (ret != 0)
 605			return ret;
 606
 607		req->best_parent_hw = dd->clk_ref;
 608	}
 609
 610	req->best_parent_rate = req->rate;
 611
 612	return 0;
 613}
 614
 615/**
 616 * omap3_noncore_dpll_set_parent - set parent for a DPLL clock
 617 * @hw: pointer to the clock to set parent for
 618 * @index: parent index to select
 619 *
 620 * Sets parent for a DPLL clock. This sets the DPLL into bypass or
 621 * locked mode. Returns 0 with success, negative error value otherwise.
 622 */
 623int omap3_noncore_dpll_set_parent(struct clk_hw *hw, u8 index)
 624{
 625	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 626	int ret;
 627
 628	if (!hw)
 629		return -EINVAL;
 630
 631	if (index)
 632		ret = _omap3_noncore_dpll_bypass(clk);
 633	else
 634		ret = _omap3_noncore_dpll_lock(clk);
 635
 636	return ret;
 637}
 638
 639/**
 640 * omap3_noncore_dpll_set_rate - set rate for a DPLL clock
 641 * @hw: pointer to the clock to set parent for
 642 * @rate: target rate for the clock
 643 * @parent_rate: rate of the parent clock
 644 *
 645 * Sets rate for a DPLL clock. First checks if the clock parent is
 646 * reference clock (in bypass mode, the rate of the clock can't be
 647 * changed) and proceeds with the rate change operation. Returns 0
 648 * with success, negative error value otherwise.
 649 */
 650int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
 651				unsigned long parent_rate)
 652{
 653	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 654	struct dpll_data *dd;
 655	u16 freqsel = 0;
 656	int ret;
 657
 658	if (!hw || !rate)
 659		return -EINVAL;
 660
 661	dd = clk->dpll_data;
 662	if (!dd)
 663		return -EINVAL;
 664
 665	if (clk_hw_get_parent(hw) != dd->clk_ref)
 666		return -EINVAL;
 667
 668	if (dd->last_rounded_rate == 0)
 669		return -EINVAL;
 670
 671	/* Freqsel is available only on OMAP343X devices */
 672	if (ti_clk_get_features()->flags & TI_CLK_DPLL_HAS_FREQSEL) {
 673		freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
 674		WARN_ON(!freqsel);
 675	}
 676
 677	pr_debug("%s: %s: set rate: locking rate to %lu.\n", __func__,
 678		 clk_hw_get_name(hw), rate);
 679
 680	ret = omap3_noncore_dpll_program(clk, freqsel);
 681
 682	return ret;
 683}
 684
 685/**
 686 * omap3_noncore_dpll_set_rate_and_parent - set rate and parent for a DPLL clock
 687 * @hw: pointer to the clock to set rate and parent for
 688 * @rate: target rate for the DPLL
 689 * @parent_rate: clock rate of the DPLL parent
 690 * @index: new parent index for the DPLL, 0 - reference, 1 - bypass
 691 *
 692 * Sets rate and parent for a DPLL clock. If new parent is the bypass
 693 * clock, only selects the parent. Otherwise proceeds with a rate
 694 * change, as this will effectively also change the parent as the
 695 * DPLL is put into locked mode. Returns 0 with success, negative error
 696 * value otherwise.
 697 */
 698int omap3_noncore_dpll_set_rate_and_parent(struct clk_hw *hw,
 699					   unsigned long rate,
 700					   unsigned long parent_rate,
 701					   u8 index)
 702{
 703	int ret;
 704
 705	if (!hw || !rate)
 706		return -EINVAL;
 707
 708	/*
 709	 * clk-ref at index[0], in which case we only need to set rate,
 710	 * the parent will be changed automatically with the lock sequence.
 711	 * With clk-bypass case we only need to change parent.
 712	 */
 713	if (index)
 714		ret = omap3_noncore_dpll_set_parent(hw, index);
 715	else
 716		ret = omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
 717
 718	return ret;
 719}
 720
 721/* DPLL autoidle read/set code */
 722
 723/**
 724 * omap3_dpll_autoidle_read - read a DPLL's autoidle bits
 725 * @clk: struct clk * of the DPLL to read
 726 *
 727 * Return the DPLL's autoidle bits, shifted down to bit 0.  Returns
 728 * -EINVAL if passed a null pointer or if the struct clk does not
 729 * appear to refer to a DPLL.
 730 */
 731static u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk)
 732{
 733	const struct dpll_data *dd;
 734	u32 v;
 735
 736	if (!clk || !clk->dpll_data)
 737		return -EINVAL;
 738
 739	dd = clk->dpll_data;
 740
 741	if (!dd->autoidle_mask)
 742		return -EINVAL;
 743
 744	v = ti_clk_ll_ops->clk_readl(&dd->autoidle_reg);
 745	v &= dd->autoidle_mask;
 746	v >>= __ffs(dd->autoidle_mask);
 747
 748	return v;
 749}
 750
 751/**
 752 * omap3_dpll_allow_idle - enable DPLL autoidle bits
 753 * @clk: struct clk * of the DPLL to operate on
 754 *
 755 * Enable DPLL automatic idle control.  This automatic idle mode
 756 * switching takes effect only when the DPLL is locked, at least on
 757 * OMAP3430.  The DPLL will enter low-power stop when its downstream
 758 * clocks are gated.  No return value.
 759 */
 760static void omap3_dpll_allow_idle(struct clk_hw_omap *clk)
 761{
 762	const struct dpll_data *dd;
 763	u32 v;
 764
 765	if (!clk || !clk->dpll_data)
 766		return;
 767
 768	dd = clk->dpll_data;
 769
 770	if (!dd->autoidle_mask)
 771		return;
 772
 773	/*
 774	 * REVISIT: CORE DPLL can optionally enter low-power bypass
 775	 * by writing 0x5 instead of 0x1.  Add some mechanism to
 776	 * optionally enter this mode.
 777	 */
 778	v = ti_clk_ll_ops->clk_readl(&dd->autoidle_reg);
 779	v &= ~dd->autoidle_mask;
 780	v |= DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask);
 781	ti_clk_ll_ops->clk_writel(v, &dd->autoidle_reg);
 782}
 783
 784/**
 785 * omap3_dpll_deny_idle - prevent DPLL from automatically idling
 786 * @clk: struct clk * of the DPLL to operate on
 787 *
 788 * Disable DPLL automatic idle control.  No return value.
 789 */
 790static void omap3_dpll_deny_idle(struct clk_hw_omap *clk)
 791{
 792	const struct dpll_data *dd;
 793	u32 v;
 794
 795	if (!clk || !clk->dpll_data)
 796		return;
 797
 798	dd = clk->dpll_data;
 799
 800	if (!dd->autoidle_mask)
 801		return;
 802
 803	v = ti_clk_ll_ops->clk_readl(&dd->autoidle_reg);
 804	v &= ~dd->autoidle_mask;
 805	v |= DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask);
 806	ti_clk_ll_ops->clk_writel(v, &dd->autoidle_reg);
 807}
 808
 809/* Clock control for DPLL outputs */
 810
 811/* Find the parent DPLL for the given clkoutx2 clock */
 812static struct clk_hw_omap *omap3_find_clkoutx2_dpll(struct clk_hw *hw)
 813{
 814	struct clk_hw_omap *pclk = NULL;
 815
 816	/* Walk up the parents of clk, looking for a DPLL */
 817	do {
 818		do {
 819			hw = clk_hw_get_parent(hw);
 820		} while (hw && (!omap2_clk_is_hw_omap(hw)));
 821		if (!hw)
 822			break;
 823		pclk = to_clk_hw_omap(hw);
 824	} while (pclk && !pclk->dpll_data);
 825
 826	/* clk does not have a DPLL as a parent?  error in the clock data */
 827	if (!pclk) {
 828		WARN_ON(1);
 829		return NULL;
 830	}
 831
 832	return pclk;
 833}
 834
 835/**
 836 * omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
 837 * @hw: pointer  struct clk_hw
 838 * @parent_rate: clock rate of the DPLL parent
 839 *
 840 * Using parent clock DPLL data, look up DPLL state.  If locked, set our
 841 * rate to the dpll_clk * 2; otherwise, just use dpll_clk.
 842 */
 843unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw,
 844				    unsigned long parent_rate)
 845{
 846	const struct dpll_data *dd;
 847	unsigned long rate;
 848	u32 v;
 849	struct clk_hw_omap *pclk = NULL;
 850
 851	if (!parent_rate)
 852		return 0;
 853
 854	pclk = omap3_find_clkoutx2_dpll(hw);
 855
 856	if (!pclk)
 857		return 0;
 858
 859	dd = pclk->dpll_data;
 860
 861	WARN_ON(!dd->enable_mask);
 862
 863	v = ti_clk_ll_ops->clk_readl(&dd->control_reg) & dd->enable_mask;
 864	v >>= __ffs(dd->enable_mask);
 865	if ((v != OMAP3XXX_EN_DPLL_LOCKED) || (dd->flags & DPLL_J_TYPE))
 866		rate = parent_rate;
 867	else
 868		rate = parent_rate * 2;
 869	return rate;
 870}
 871
 872/**
 873 * omap3_core_dpll_save_context - Save the m and n values of the divider
 874 * @hw: pointer  struct clk_hw
 875 *
 876 * Before the dpll registers are lost save the last rounded rate m and n
 877 * and the enable mask.
 878 */
 879int omap3_core_dpll_save_context(struct clk_hw *hw)
 880{
 881	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 882	struct dpll_data *dd;
 883	u32 v;
 884
 885	dd = clk->dpll_data;
 886
 887	v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
 888	clk->context = (v & dd->enable_mask) >> __ffs(dd->enable_mask);
 889
 890	if (clk->context == DPLL_LOCKED) {
 891		v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
 892		dd->last_rounded_m = (v & dd->mult_mask) >>
 893						__ffs(dd->mult_mask);
 894		dd->last_rounded_n = ((v & dd->div1_mask) >>
 895						__ffs(dd->div1_mask)) + 1;
 896	}
 897
 898	return 0;
 899}
 900
 901/**
 902 * omap3_core_dpll_restore_context - restore the m and n values of the divider
 903 * @hw: pointer  struct clk_hw
 904 *
 905 * Restore the last rounded rate m and n
 906 * and the enable mask.
 907 */
 908void omap3_core_dpll_restore_context(struct clk_hw *hw)
 909{
 910	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 911	const struct dpll_data *dd;
 912	u32 v;
 913
 914	dd = clk->dpll_data;
 915
 916	if (clk->context == DPLL_LOCKED) {
 917		_omap3_dpll_write_clken(clk, 0x4);
 918		_omap3_wait_dpll_status(clk, 0);
 919
 920		v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
 921		v &= ~(dd->mult_mask | dd->div1_mask);
 922		v |= dd->last_rounded_m << __ffs(dd->mult_mask);
 923		v |= (dd->last_rounded_n - 1) << __ffs(dd->div1_mask);
 924		ti_clk_ll_ops->clk_writel(v, &dd->mult_div1_reg);
 925
 926		_omap3_dpll_write_clken(clk, DPLL_LOCKED);
 927		_omap3_wait_dpll_status(clk, 1);
 928	} else {
 929		_omap3_dpll_write_clken(clk, clk->context);
 930	}
 931}
 932
 933/**
 934 * omap3_noncore_dpll_save_context - Save the m and n values of the divider
 935 * @hw: pointer  struct clk_hw
 936 *
 937 * Before the dpll registers are lost save the last rounded rate m and n
 938 * and the enable mask.
 939 */
 940int omap3_noncore_dpll_save_context(struct clk_hw *hw)
 941{
 942	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 943	struct dpll_data *dd;
 944	u32 v;
 945
 946	dd = clk->dpll_data;
 947
 948	v = ti_clk_ll_ops->clk_readl(&dd->control_reg);
 949	clk->context = (v & dd->enable_mask) >> __ffs(dd->enable_mask);
 950
 951	if (clk->context == DPLL_LOCKED) {
 952		v = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
 953		dd->last_rounded_m = (v & dd->mult_mask) >>
 954						__ffs(dd->mult_mask);
 955		dd->last_rounded_n = ((v & dd->div1_mask) >>
 956						__ffs(dd->div1_mask)) + 1;
 957	}
 958
 959	return 0;
 960}
 961
 962/**
 963 * omap3_noncore_dpll_restore_context - restore the m and n values of the divider
 964 * @hw: pointer  struct clk_hw
 965 *
 966 * Restore the last rounded rate m and n
 967 * and the enable mask.
 968 */
 969void omap3_noncore_dpll_restore_context(struct clk_hw *hw)
 970{
 971	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
 972	const struct dpll_data *dd;
 973	u32 ctrl, mult_div1;
 974
 975	dd = clk->dpll_data;
 976
 977	ctrl = ti_clk_ll_ops->clk_readl(&dd->control_reg);
 978	mult_div1 = ti_clk_ll_ops->clk_readl(&dd->mult_div1_reg);
 979
 980	if (clk->context == ((ctrl & dd->enable_mask) >>
 981			     __ffs(dd->enable_mask)) &&
 982	    dd->last_rounded_m == ((mult_div1 & dd->mult_mask) >>
 983				   __ffs(dd->mult_mask)) &&
 984	    dd->last_rounded_n == ((mult_div1 & dd->div1_mask) >>
 985				   __ffs(dd->div1_mask)) + 1) {
 986		/* nothing to be done */
 987		return;
 988	}
 989
 990	if (clk->context == DPLL_LOCKED)
 991		omap3_noncore_dpll_program(clk, 0);
 992	else
 993		_omap3_dpll_write_clken(clk, clk->context);
 994}
 995
 996/* OMAP3/4 non-CORE DPLL clkops */
 997const struct clk_hw_omap_ops clkhwops_omap3_dpll = {
 998	.allow_idle	= omap3_dpll_allow_idle,
 999	.deny_idle	= omap3_dpll_deny_idle,
1000};
1001
1002/**
1003 * omap3_dpll4_set_rate - set rate for omap3 per-dpll
1004 * @hw: clock to change
1005 * @rate: target rate for clock
1006 * @parent_rate: clock rate of the DPLL parent
1007 *
1008 * Check if the current SoC supports the per-dpll reprogram operation
1009 * or not, and then do the rate change if supported. Returns -EINVAL
1010 * if not supported, 0 for success, and potential error codes from the
1011 * clock rate change.
1012 */
1013int omap3_dpll4_set_rate(struct clk_hw *hw, unsigned long rate,
1014			 unsigned long parent_rate)
1015{
1016	/*
1017	 * According to the 12-5 CDP code from TI, "Limitation 2.5"
1018	 * on 3430ES1 prevents us from changing DPLL multipliers or dividers
1019	 * on DPLL4.
1020	 */
1021	if (ti_clk_get_features()->flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
1022		pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
1023		return -EINVAL;
1024	}
1025
1026	return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
1027}
1028
1029/**
1030 * omap3_dpll4_set_rate_and_parent - set rate and parent for omap3 per-dpll
1031 * @hw: clock to change
1032 * @rate: target rate for clock
1033 * @parent_rate: rate of the parent clock
1034 * @index: parent index, 0 - reference clock, 1 - bypass clock
1035 *
1036 * Check if the current SoC support the per-dpll reprogram operation
1037 * or not, and then do the rate + parent change if supported. Returns
1038 * -EINVAL if not supported, 0 for success, and potential error codes
1039 * from the clock rate change.
1040 */
1041int omap3_dpll4_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
1042				    unsigned long parent_rate, u8 index)
1043{
1044	if (ti_clk_get_features()->flags & TI_CLK_DPLL4_DENY_REPROGRAM) {
1045		pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n");
1046		return -EINVAL;
1047	}
1048
1049	return omap3_noncore_dpll_set_rate_and_parent(hw, rate, parent_rate,
1050						      index);
1051}
1052
1053/* Apply DM3730 errata sprz319 advisory 2.1. */
1054static bool omap3_dpll5_apply_errata(struct clk_hw *hw,
1055				     unsigned long parent_rate)
1056{
1057	struct omap3_dpll5_settings {
1058		unsigned int rate, m, n;
1059	};
1060
1061	static const struct omap3_dpll5_settings precomputed[] = {
1062		/*
1063		 * From DM3730 errata advisory 2.1, table 35 and 36.
1064		 * The N value is increased by 1 compared to the tables as the
1065		 * errata lists register values while last_rounded_field is the
1066		 * real divider value.
1067		 */
1068		{ 12000000,  80,  0 + 1 },
1069		{ 13000000, 443,  5 + 1 },
1070		{ 19200000,  50,  0 + 1 },
1071		{ 26000000, 443, 11 + 1 },
1072		{ 38400000,  25,  0 + 1 }
1073	};
1074
1075	const struct omap3_dpll5_settings *d;
1076	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
1077	struct dpll_data *dd;
1078	unsigned int i;
1079
1080	for (i = 0; i < ARRAY_SIZE(precomputed); ++i) {
1081		if (parent_rate == precomputed[i].rate)
1082			break;
1083	}
1084
1085	if (i == ARRAY_SIZE(precomputed))
1086		return false;
1087
1088	d = &precomputed[i];
1089
1090	/* Update the M, N and rounded rate values and program the DPLL. */
1091	dd = clk->dpll_data;
1092	dd->last_rounded_m = d->m;
1093	dd->last_rounded_n = d->n;
1094	dd->last_rounded_rate = div_u64((u64)parent_rate * d->m, d->n);
1095	omap3_noncore_dpll_program(clk, 0);
1096
1097	return true;
1098}
1099
1100/**
1101 * omap3_dpll5_set_rate - set rate for omap3 dpll5
1102 * @hw: clock to change
1103 * @rate: target rate for clock
1104 * @parent_rate: rate of the parent clock
1105 *
1106 * Set rate for the DPLL5 clock. Apply the sprz319 advisory 2.1 on OMAP36xx if
1107 * the DPLL is used for USB host (detected through the requested rate).
1108 */
1109int omap3_dpll5_set_rate(struct clk_hw *hw, unsigned long rate,
1110			 unsigned long parent_rate)
1111{
1112	if (rate == OMAP3_DPLL5_FREQ_FOR_USBHOST * 8) {
1113		if (omap3_dpll5_apply_errata(hw, parent_rate))
1114			return 0;
1115	}
1116
1117	return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
1118}
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