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v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Purna Chandra Mandal,<purna.mandal@microchip.com>
   4 * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
   5 */
   6#include <linux/clk-provider.h>
   7#include <linux/delay.h>
   8#include <linux/device.h>
   9#include <linux/interrupt.h>
  10#include <linux/io.h>
  11#include <linux/iopoll.h>
  12#include <asm/mach-pic32/pic32.h>
  13#include <asm/traps.h>
  14
  15#include "clk-core.h"
  16
  17/* OSCCON Reg fields */
  18#define OSC_CUR_MASK		0x07
  19#define OSC_CUR_SHIFT		12
  20#define OSC_NEW_MASK		0x07
  21#define OSC_NEW_SHIFT		8
  22#define OSC_SWEN		BIT(0)
  23
  24/* SPLLCON Reg fields */
  25#define PLL_RANGE_MASK		0x07
  26#define PLL_RANGE_SHIFT		0
  27#define PLL_ICLK_MASK		0x01
  28#define PLL_ICLK_SHIFT		7
  29#define PLL_IDIV_MASK		0x07
  30#define PLL_IDIV_SHIFT		8
  31#define PLL_ODIV_MASK		0x07
  32#define PLL_ODIV_SHIFT		24
  33#define PLL_MULT_MASK		0x7F
  34#define PLL_MULT_SHIFT		16
  35#define PLL_MULT_MAX		128
  36#define PLL_ODIV_MIN		1
  37#define PLL_ODIV_MAX		5
  38
  39/* Peripheral Bus Clock Reg Fields */
  40#define PB_DIV_MASK		0x7f
  41#define PB_DIV_SHIFT		0
  42#define PB_DIV_READY		BIT(11)
  43#define PB_DIV_ENABLE		BIT(15)
  44#define PB_DIV_MAX		128
  45#define PB_DIV_MIN		0
  46
  47/* Reference Oscillator Control Reg fields */
  48#define REFO_SEL_MASK		0x0f
  49#define REFO_SEL_SHIFT		0
  50#define REFO_ACTIVE		BIT(8)
  51#define REFO_DIVSW_EN		BIT(9)
  52#define REFO_OE			BIT(12)
  53#define REFO_ON			BIT(15)
  54#define REFO_DIV_SHIFT		16
  55#define REFO_DIV_MASK		0x7fff
  56
  57/* Reference Oscillator Trim Register Fields */
  58#define REFO_TRIM_REG		0x10
  59#define REFO_TRIM_MASK		0x1ff
  60#define REFO_TRIM_SHIFT		23
  61#define REFO_TRIM_MAX		511
  62
  63/* Mux Slew Control Register fields */
  64#define SLEW_BUSY		BIT(0)
  65#define SLEW_DOWNEN		BIT(1)
  66#define SLEW_UPEN		BIT(2)
  67#define SLEW_DIV		0x07
  68#define SLEW_DIV_SHIFT		8
  69#define SLEW_SYSDIV		0x0f
  70#define SLEW_SYSDIV_SHIFT	20
  71
  72/* Clock Poll Timeout */
  73#define LOCK_TIMEOUT_US         USEC_PER_MSEC
  74
  75/* SoC specific clock needed during SPLL clock rate switch */
  76static struct clk_hw *pic32_sclk_hw;
  77
  78/* add instruction pipeline delay while CPU clock is in-transition. */
  79#define cpu_nop5()			\
  80do {					\
  81	__asm__ __volatile__("nop");	\
  82	__asm__ __volatile__("nop");	\
  83	__asm__ __volatile__("nop");	\
  84	__asm__ __volatile__("nop");	\
  85	__asm__ __volatile__("nop");	\
  86} while (0)
  87
  88/* Perpheral bus clocks */
  89struct pic32_periph_clk {
  90	struct clk_hw hw;
  91	void __iomem *ctrl_reg;
  92	struct pic32_clk_common *core;
  93};
  94
  95#define clkhw_to_pbclk(_hw)	container_of(_hw, struct pic32_periph_clk, hw)
  96
  97static int pbclk_is_enabled(struct clk_hw *hw)
  98{
  99	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 100
 101	return readl(pb->ctrl_reg) & PB_DIV_ENABLE;
 102}
 103
 104static int pbclk_enable(struct clk_hw *hw)
 105{
 106	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 107
 108	writel(PB_DIV_ENABLE, PIC32_SET(pb->ctrl_reg));
 109	return 0;
 110}
 111
 112static void pbclk_disable(struct clk_hw *hw)
 113{
 114	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 115
 116	writel(PB_DIV_ENABLE, PIC32_CLR(pb->ctrl_reg));
 117}
 118
 119static unsigned long calc_best_divided_rate(unsigned long rate,
 120					    unsigned long parent_rate,
 121					    u32 divider_max,
 122					    u32 divider_min)
 123{
 124	unsigned long divided_rate, divided_rate_down, best_rate;
 125	unsigned long div, div_up;
 126
 127	/* eq. clk_rate = parent_rate / divider.
 128	 *
 129	 * Find best divider to produce closest of target divided rate.
 130	 */
 131	div = parent_rate / rate;
 132	div = clamp_val(div, divider_min, divider_max);
 133	div_up = clamp_val(div + 1, divider_min, divider_max);
 134
 135	divided_rate = parent_rate / div;
 136	divided_rate_down = parent_rate / div_up;
 137	if (abs(rate - divided_rate_down) < abs(rate - divided_rate))
 138		best_rate = divided_rate_down;
 139	else
 140		best_rate = divided_rate;
 141
 142	return best_rate;
 143}
 144
 145static inline u32 pbclk_read_pbdiv(struct pic32_periph_clk *pb)
 146{
 147	return ((readl(pb->ctrl_reg) >> PB_DIV_SHIFT) & PB_DIV_MASK) + 1;
 148}
 149
 150static unsigned long pbclk_recalc_rate(struct clk_hw *hw,
 151				       unsigned long parent_rate)
 152{
 153	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 154
 155	return parent_rate / pbclk_read_pbdiv(pb);
 156}
 157
 158static long pbclk_round_rate(struct clk_hw *hw, unsigned long rate,
 159			     unsigned long *parent_rate)
 160{
 161	return calc_best_divided_rate(rate, *parent_rate,
 162				      PB_DIV_MAX, PB_DIV_MIN);
 163}
 164
 165static int pbclk_set_rate(struct clk_hw *hw, unsigned long rate,
 166			  unsigned long parent_rate)
 167{
 168	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 169	unsigned long flags;
 170	u32 v, div;
 171	int err;
 172
 173	/* check & wait for DIV_READY */
 174	err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
 175				 1, LOCK_TIMEOUT_US);
 176	if (err)
 177		return err;
 178
 179	/* calculate clkdiv and best rate */
 180	div = DIV_ROUND_CLOSEST(parent_rate, rate);
 181
 182	spin_lock_irqsave(&pb->core->reg_lock, flags);
 183
 184	/* apply new div */
 185	v = readl(pb->ctrl_reg);
 186	v &= ~PB_DIV_MASK;
 187	v |= (div - 1);
 188
 189	pic32_syskey_unlock();
 190
 191	writel(v, pb->ctrl_reg);
 192
 193	spin_unlock_irqrestore(&pb->core->reg_lock, flags);
 194
 195	/* wait again for DIV_READY */
 196	err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
 197				 1, LOCK_TIMEOUT_US);
 198	if (err)
 199		return err;
 200
 201	/* confirm that new div is applied correctly */
 202	return (pbclk_read_pbdiv(pb) == div) ? 0 : -EBUSY;
 203}
 204
 205const struct clk_ops pic32_pbclk_ops = {
 206	.enable		= pbclk_enable,
 207	.disable	= pbclk_disable,
 208	.is_enabled	= pbclk_is_enabled,
 209	.recalc_rate	= pbclk_recalc_rate,
 210	.round_rate	= pbclk_round_rate,
 211	.set_rate	= pbclk_set_rate,
 212};
 213
 214struct clk *pic32_periph_clk_register(const struct pic32_periph_clk_data *desc,
 215				      struct pic32_clk_common *core)
 216{
 217	struct pic32_periph_clk *pbclk;
 218	struct clk *clk;
 219
 220	pbclk = devm_kzalloc(core->dev, sizeof(*pbclk), GFP_KERNEL);
 221	if (!pbclk)
 222		return ERR_PTR(-ENOMEM);
 223
 224	pbclk->hw.init = &desc->init_data;
 225	pbclk->core = core;
 226	pbclk->ctrl_reg = desc->ctrl_reg + core->iobase;
 227
 228	clk = devm_clk_register(core->dev, &pbclk->hw);
 229	if (IS_ERR(clk)) {
 230		dev_err(core->dev, "%s: clk_register() failed\n", __func__);
 231		devm_kfree(core->dev, pbclk);
 232	}
 233
 234	return clk;
 235}
 236
 237/* Reference oscillator operations */
 238struct pic32_ref_osc {
 239	struct clk_hw hw;
 240	void __iomem *ctrl_reg;
 241	const u32 *parent_map;
 242	struct pic32_clk_common *core;
 243};
 244
 245#define clkhw_to_refosc(_hw)	container_of(_hw, struct pic32_ref_osc, hw)
 246
 247static int roclk_is_enabled(struct clk_hw *hw)
 248{
 249	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 250
 251	return readl(refo->ctrl_reg) & REFO_ON;
 252}
 253
 254static int roclk_enable(struct clk_hw *hw)
 255{
 256	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 257
 258	writel(REFO_ON | REFO_OE, PIC32_SET(refo->ctrl_reg));
 259	return 0;
 260}
 261
 262static void roclk_disable(struct clk_hw *hw)
 263{
 264	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 265
 266	writel(REFO_ON | REFO_OE, PIC32_CLR(refo->ctrl_reg));
 267}
 268
 269static void roclk_init(struct clk_hw *hw)
 270{
 271	/* initialize clock in disabled state */
 272	roclk_disable(hw);
 
 
 273}
 274
 275static u8 roclk_get_parent(struct clk_hw *hw)
 276{
 277	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 278	u32 v, i;
 279
 280	v = (readl(refo->ctrl_reg) >> REFO_SEL_SHIFT) & REFO_SEL_MASK;
 281
 282	if (!refo->parent_map)
 283		return v;
 284
 285	for (i = 0; i < clk_hw_get_num_parents(hw); i++)
 286		if (refo->parent_map[i] == v)
 287			return i;
 288
 289	return -EINVAL;
 290}
 291
 292static unsigned long roclk_calc_rate(unsigned long parent_rate,
 293				     u32 rodiv, u32 rotrim)
 294{
 295	u64 rate64;
 296
 297	/* fout = fin / [2 * {div + (trim / 512)}]
 298	 *	= fin * 512 / [1024 * div + 2 * trim]
 299	 *	= fin * 256 / (512 * div + trim)
 300	 *	= (fin << 8) / ((div << 9) + trim)
 301	 */
 302	if (rotrim) {
 303		rodiv = (rodiv << 9) + rotrim;
 304		rate64 = parent_rate;
 305		rate64 <<= 8;
 306		do_div(rate64, rodiv);
 307	} else if (rodiv) {
 308		rate64 = parent_rate / (rodiv << 1);
 309	} else {
 310		rate64 = parent_rate;
 311	}
 312	return rate64;
 313}
 314
 315static void roclk_calc_div_trim(unsigned long rate,
 316				unsigned long parent_rate,
 317				u32 *rodiv_p, u32 *rotrim_p)
 318{
 319	u32 div, rotrim, rodiv;
 320	u64 frac;
 321
 322	/* Find integer approximation of floating-point arithmetic.
 323	 *      fout = fin / [2 * {rodiv + (rotrim / 512)}] ... (1)
 324	 * i.e. fout = fin / 2 * DIV
 325	 *      whereas DIV = rodiv + (rotrim / 512)
 326	 *
 327	 * Since kernel does not perform floating-point arithmatic so
 328	 * (rotrim/512) will be zero. And DIV & rodiv will result same.
 329	 *
 330	 * ie. fout = (fin * 256) / [(512 * rodiv) + rotrim]  ... from (1)
 331	 * ie. rotrim = ((fin * 256) / fout) - (512 * DIV)
 332	 */
 333	if (parent_rate <= rate) {
 334		div = 0;
 335		frac = 0;
 336		rodiv = 0;
 337		rotrim = 0;
 338	} else {
 339		div = parent_rate / (rate << 1);
 340		frac = parent_rate;
 341		frac <<= 8;
 342		do_div(frac, rate);
 343		frac -= (u64)(div << 9);
 344
 345		rodiv = (div > REFO_DIV_MASK) ? REFO_DIV_MASK : div;
 346		rotrim = (frac >= REFO_TRIM_MAX) ? REFO_TRIM_MAX : frac;
 347	}
 348
 349	if (rodiv_p)
 350		*rodiv_p = rodiv;
 351
 352	if (rotrim_p)
 353		*rotrim_p = rotrim;
 354}
 355
 356static unsigned long roclk_recalc_rate(struct clk_hw *hw,
 357				       unsigned long parent_rate)
 358{
 359	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 360	u32 v, rodiv, rotrim;
 361
 362	/* get rodiv */
 363	v = readl(refo->ctrl_reg);
 364	rodiv = (v >> REFO_DIV_SHIFT) & REFO_DIV_MASK;
 365
 366	/* get trim */
 367	v = readl(refo->ctrl_reg + REFO_TRIM_REG);
 368	rotrim = (v >> REFO_TRIM_SHIFT) & REFO_TRIM_MASK;
 369
 370	return roclk_calc_rate(parent_rate, rodiv, rotrim);
 371}
 372
 373static long roclk_round_rate(struct clk_hw *hw, unsigned long rate,
 374			     unsigned long *parent_rate)
 375{
 376	u32 rotrim, rodiv;
 377
 378	/* calculate dividers for new rate */
 379	roclk_calc_div_trim(rate, *parent_rate, &rodiv, &rotrim);
 380
 381	/* caclulate new rate (rounding) based on new rodiv & rotrim */
 382	return roclk_calc_rate(*parent_rate, rodiv, rotrim);
 383}
 384
 385static int roclk_determine_rate(struct clk_hw *hw,
 386				struct clk_rate_request *req)
 387{
 388	struct clk_hw *parent_clk, *best_parent_clk = NULL;
 389	unsigned int i, delta, best_delta = -1;
 390	unsigned long parent_rate, best_parent_rate = 0;
 391	unsigned long best = 0, nearest_rate;
 392
 393	/* find a parent which can generate nearest clkrate >= rate */
 394	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
 395		/* get parent */
 396		parent_clk = clk_hw_get_parent_by_index(hw, i);
 397		if (!parent_clk)
 398			continue;
 399
 400		/* skip if parent runs slower than target rate */
 401		parent_rate = clk_hw_get_rate(parent_clk);
 402		if (req->rate > parent_rate)
 403			continue;
 404
 405		nearest_rate = roclk_round_rate(hw, req->rate, &parent_rate);
 406		delta = abs(nearest_rate - req->rate);
 407		if ((nearest_rate >= req->rate) && (delta < best_delta)) {
 408			best_parent_clk = parent_clk;
 409			best_parent_rate = parent_rate;
 410			best = nearest_rate;
 411			best_delta = delta;
 412
 413			if (delta == 0)
 414				break;
 415		}
 416	}
 417
 418	/* if no match found, retain old rate */
 419	if (!best_parent_clk) {
 420		pr_err("%s:%s, no parent found for rate %lu.\n",
 421		       __func__, clk_hw_get_name(hw), req->rate);
 422		return clk_hw_get_rate(hw);
 423	}
 424
 425	pr_debug("%s,rate %lu, best_parent(%s, %lu), best %lu, delta %d\n",
 426		 clk_hw_get_name(hw), req->rate,
 427		 clk_hw_get_name(best_parent_clk), best_parent_rate,
 428		 best, best_delta);
 429
 430	if (req->best_parent_rate)
 431		req->best_parent_rate = best_parent_rate;
 432
 433	if (req->best_parent_hw)
 434		req->best_parent_hw = best_parent_clk;
 435
 436	return best;
 437}
 438
 439static int roclk_set_parent(struct clk_hw *hw, u8 index)
 440{
 441	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 442	unsigned long flags;
 443	u32 v;
 444	int err;
 445
 446	if (refo->parent_map)
 447		index = refo->parent_map[index];
 448
 449	/* wait until ACTIVE bit is zero or timeout */
 450	err = readl_poll_timeout(refo->ctrl_reg, v, !(v & REFO_ACTIVE),
 451				 1, LOCK_TIMEOUT_US);
 452	if (err) {
 453		pr_err("%s: poll failed, clk active\n", clk_hw_get_name(hw));
 454		return err;
 455	}
 456
 457	spin_lock_irqsave(&refo->core->reg_lock, flags);
 458
 459	pic32_syskey_unlock();
 460
 461	/* calculate & apply new */
 462	v = readl(refo->ctrl_reg);
 463	v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
 464	v |= index << REFO_SEL_SHIFT;
 465
 466	writel(v, refo->ctrl_reg);
 467
 468	spin_unlock_irqrestore(&refo->core->reg_lock, flags);
 469
 470	return 0;
 471}
 472
 473static int roclk_set_rate_and_parent(struct clk_hw *hw,
 474				     unsigned long rate,
 475				     unsigned long parent_rate,
 476				     u8 index)
 477{
 478	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 479	unsigned long flags;
 480	u32 trim, rodiv, v;
 481	int err;
 482
 483	/* calculate new rodiv & rotrim for new rate */
 484	roclk_calc_div_trim(rate, parent_rate, &rodiv, &trim);
 485
 486	pr_debug("parent_rate = %lu, rate = %lu, div = %d, trim = %d\n",
 487		 parent_rate, rate, rodiv, trim);
 488
 489	/* wait till source change is active */
 490	err = readl_poll_timeout(refo->ctrl_reg, v,
 491				 !(v & (REFO_ACTIVE | REFO_DIVSW_EN)),
 492				 1, LOCK_TIMEOUT_US);
 493	if (err) {
 494		pr_err("%s: poll timedout, clock is still active\n", __func__);
 495		return err;
 496	}
 497
 498	spin_lock_irqsave(&refo->core->reg_lock, flags);
 499	v = readl(refo->ctrl_reg);
 500
 501	pic32_syskey_unlock();
 502
 503	/* apply parent, if required */
 504	if (refo->parent_map)
 505		index = refo->parent_map[index];
 506
 507	v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
 508	v |= index << REFO_SEL_SHIFT;
 509
 510	/* apply RODIV */
 511	v &= ~(REFO_DIV_MASK << REFO_DIV_SHIFT);
 512	v |= rodiv << REFO_DIV_SHIFT;
 513	writel(v, refo->ctrl_reg);
 514
 515	/* apply ROTRIM */
 516	v = readl(refo->ctrl_reg + REFO_TRIM_REG);
 517	v &= ~(REFO_TRIM_MASK << REFO_TRIM_SHIFT);
 518	v |= trim << REFO_TRIM_SHIFT;
 519	writel(v, refo->ctrl_reg + REFO_TRIM_REG);
 520
 521	/* enable & activate divider switching */
 522	writel(REFO_ON | REFO_DIVSW_EN, PIC32_SET(refo->ctrl_reg));
 523
 524	/* wait till divswen is in-progress */
 525	err = readl_poll_timeout_atomic(refo->ctrl_reg, v, !(v & REFO_DIVSW_EN),
 526					1, LOCK_TIMEOUT_US);
 527	/* leave the clk gated as it was */
 528	writel(REFO_ON, PIC32_CLR(refo->ctrl_reg));
 529
 530	spin_unlock_irqrestore(&refo->core->reg_lock, flags);
 531
 532	return err;
 533}
 534
 535static int roclk_set_rate(struct clk_hw *hw, unsigned long rate,
 536			  unsigned long parent_rate)
 537{
 538	u8 index = roclk_get_parent(hw);
 539
 540	return roclk_set_rate_and_parent(hw, rate, parent_rate, index);
 541}
 542
 543const struct clk_ops pic32_roclk_ops = {
 544	.enable			= roclk_enable,
 545	.disable		= roclk_disable,
 546	.is_enabled		= roclk_is_enabled,
 547	.get_parent		= roclk_get_parent,
 548	.set_parent		= roclk_set_parent,
 549	.determine_rate		= roclk_determine_rate,
 550	.recalc_rate		= roclk_recalc_rate,
 551	.set_rate_and_parent	= roclk_set_rate_and_parent,
 552	.set_rate		= roclk_set_rate,
 553	.init			= roclk_init,
 554};
 555
 556struct clk *pic32_refo_clk_register(const struct pic32_ref_osc_data *data,
 557				    struct pic32_clk_common *core)
 558{
 559	struct pic32_ref_osc *refo;
 560	struct clk *clk;
 561
 562	refo = devm_kzalloc(core->dev, sizeof(*refo), GFP_KERNEL);
 563	if (!refo)
 564		return ERR_PTR(-ENOMEM);
 565
 566	refo->core = core;
 567	refo->hw.init = &data->init_data;
 568	refo->ctrl_reg = data->ctrl_reg + core->iobase;
 569	refo->parent_map = data->parent_map;
 570
 571	clk = devm_clk_register(core->dev, &refo->hw);
 572	if (IS_ERR(clk))
 573		dev_err(core->dev, "%s: clk_register() failed\n", __func__);
 574
 575	return clk;
 576}
 577
 578struct pic32_sys_pll {
 579	struct clk_hw hw;
 580	void __iomem *ctrl_reg;
 581	void __iomem *status_reg;
 582	u32 lock_mask;
 583	u32 idiv; /* PLL iclk divider, treated fixed */
 584	struct pic32_clk_common *core;
 585};
 586
 587#define clkhw_to_spll(_hw)	container_of(_hw, struct pic32_sys_pll, hw)
 588
 589static inline u32 spll_odiv_to_divider(u32 odiv)
 590{
 591	odiv = clamp_val(odiv, PLL_ODIV_MIN, PLL_ODIV_MAX);
 592
 593	return 1 << odiv;
 594}
 595
 596static unsigned long spll_calc_mult_div(struct pic32_sys_pll *pll,
 597					unsigned long rate,
 598					unsigned long parent_rate,
 599					u32 *mult_p, u32 *odiv_p)
 600{
 601	u32 mul, div, best_mul = 1, best_div = 1;
 602	unsigned long new_rate, best_rate = rate;
 603	unsigned int best_delta = -1, delta, match_found = 0;
 604	u64 rate64;
 605
 606	parent_rate /= pll->idiv;
 607
 608	for (mul = 1; mul <= PLL_MULT_MAX; mul++) {
 609		for (div = PLL_ODIV_MIN; div <= PLL_ODIV_MAX; div++) {
 610			rate64 = parent_rate;
 611			rate64 *= mul;
 612			do_div(rate64, 1 << div);
 613			new_rate = rate64;
 614			delta = abs(rate - new_rate);
 615			if ((new_rate >= rate) && (delta < best_delta)) {
 616				best_delta = delta;
 617				best_rate = new_rate;
 618				best_mul = mul;
 619				best_div = div;
 620				match_found = 1;
 621			}
 622		}
 623	}
 624
 625	if (!match_found) {
 626		pr_warn("spll: no match found\n");
 627		return 0;
 628	}
 629
 630	pr_debug("rate %lu, par_rate %lu/mult %u, div %u, best_rate %lu\n",
 631		 rate, parent_rate, best_mul, best_div, best_rate);
 632
 633	if (mult_p)
 634		*mult_p = best_mul - 1;
 635
 636	if (odiv_p)
 637		*odiv_p = best_div;
 638
 639	return best_rate;
 640}
 641
 642static unsigned long spll_clk_recalc_rate(struct clk_hw *hw,
 643					  unsigned long parent_rate)
 644{
 645	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 646	unsigned long pll_in_rate;
 647	u32 mult, odiv, div, v;
 648	u64 rate64;
 649
 650	v = readl(pll->ctrl_reg);
 651	odiv = ((v >> PLL_ODIV_SHIFT) & PLL_ODIV_MASK);
 652	mult = ((v >> PLL_MULT_SHIFT) & PLL_MULT_MASK) + 1;
 653	div = spll_odiv_to_divider(odiv);
 654
 655	/* pll_in_rate = parent_rate / idiv
 656	 * pll_out_rate = pll_in_rate * mult / div;
 657	 */
 658	pll_in_rate = parent_rate / pll->idiv;
 659	rate64 = pll_in_rate;
 660	rate64 *= mult;
 661	do_div(rate64, div);
 662
 663	return rate64;
 664}
 665
 666static long spll_clk_round_rate(struct clk_hw *hw, unsigned long rate,
 667				unsigned long *parent_rate)
 668{
 669	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 670
 671	return spll_calc_mult_div(pll, rate, *parent_rate, NULL, NULL);
 672}
 673
 674static int spll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 675			     unsigned long parent_rate)
 676{
 677	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 678	unsigned long ret, flags;
 679	u32 mult, odiv, v;
 680	int err;
 681
 682	ret = spll_calc_mult_div(pll, rate, parent_rate, &mult, &odiv);
 683	if (!ret)
 684		return -EINVAL;
 685
 686	/*
 687	 * We can't change SPLL counters when it is in-active use
 688	 * by SYSCLK. So check before applying new counters/rate.
 689	 */
 690
 691	/* Is spll_clk active parent of sys_clk ? */
 692	if (unlikely(clk_hw_get_parent(pic32_sclk_hw) == hw)) {
 693		pr_err("%s: failed, clk in-use\n", __func__);
 694		return -EBUSY;
 695	}
 696
 697	spin_lock_irqsave(&pll->core->reg_lock, flags);
 698
 699	/* apply new multiplier & divisor */
 700	v = readl(pll->ctrl_reg);
 701	v &= ~(PLL_MULT_MASK << PLL_MULT_SHIFT);
 702	v &= ~(PLL_ODIV_MASK << PLL_ODIV_SHIFT);
 703	v |= (mult << PLL_MULT_SHIFT) | (odiv << PLL_ODIV_SHIFT);
 704
 705	/* sys unlock before write */
 706	pic32_syskey_unlock();
 707
 708	writel(v, pll->ctrl_reg);
 709	cpu_relax();
 710
 711	/* insert few nops (5-stage) to ensure CPU does not hang */
 712	cpu_nop5();
 713	cpu_nop5();
 714
 715	/* Wait until PLL is locked (maximum 100 usecs). */
 716	err = readl_poll_timeout_atomic(pll->status_reg, v,
 717					v & pll->lock_mask, 1, 100);
 718	spin_unlock_irqrestore(&pll->core->reg_lock, flags);
 719
 720	return err;
 721}
 722
 723/* SPLL clock operation */
 724const struct clk_ops pic32_spll_ops = {
 725	.recalc_rate	= spll_clk_recalc_rate,
 726	.round_rate	= spll_clk_round_rate,
 727	.set_rate	= spll_clk_set_rate,
 728};
 729
 730struct clk *pic32_spll_clk_register(const struct pic32_sys_pll_data *data,
 731				    struct pic32_clk_common *core)
 732{
 733	struct pic32_sys_pll *spll;
 734	struct clk *clk;
 735
 736	spll = devm_kzalloc(core->dev, sizeof(*spll), GFP_KERNEL);
 737	if (!spll)
 738		return ERR_PTR(-ENOMEM);
 739
 740	spll->core = core;
 741	spll->hw.init = &data->init_data;
 742	spll->ctrl_reg = data->ctrl_reg + core->iobase;
 743	spll->status_reg = data->status_reg + core->iobase;
 744	spll->lock_mask = data->lock_mask;
 745
 746	/* cache PLL idiv; PLL driver uses it as constant.*/
 747	spll->idiv = (readl(spll->ctrl_reg) >> PLL_IDIV_SHIFT) & PLL_IDIV_MASK;
 748	spll->idiv += 1;
 749
 750	clk = devm_clk_register(core->dev, &spll->hw);
 751	if (IS_ERR(clk))
 752		dev_err(core->dev, "sys_pll: clk_register() failed\n");
 753
 754	return clk;
 755}
 756
 757/* System mux clock(aka SCLK) */
 758
 759struct pic32_sys_clk {
 760	struct clk_hw hw;
 761	void __iomem *mux_reg;
 762	void __iomem *slew_reg;
 763	u32 slew_div;
 764	const u32 *parent_map;
 765	struct pic32_clk_common *core;
 766};
 767
 768#define clkhw_to_sys_clk(_hw)	container_of(_hw, struct pic32_sys_clk, hw)
 769
 770static unsigned long sclk_get_rate(struct clk_hw *hw, unsigned long parent_rate)
 771{
 772	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 773	u32 div;
 774
 775	div = (readl(sclk->slew_reg) >> SLEW_SYSDIV_SHIFT) & SLEW_SYSDIV;
 776	div += 1; /* sys-div to divider */
 777
 778	return parent_rate / div;
 779}
 780
 781static long sclk_round_rate(struct clk_hw *hw, unsigned long rate,
 782			    unsigned long *parent_rate)
 783{
 784	return calc_best_divided_rate(rate, *parent_rate, SLEW_SYSDIV, 1);
 785}
 786
 787static int sclk_set_rate(struct clk_hw *hw,
 788			 unsigned long rate, unsigned long parent_rate)
 789{
 790	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 791	unsigned long flags;
 792	u32 v, div;
 793	int err;
 794
 795	div = parent_rate / rate;
 796
 797	spin_lock_irqsave(&sclk->core->reg_lock, flags);
 798
 799	/* apply new div */
 800	v = readl(sclk->slew_reg);
 801	v &= ~(SLEW_SYSDIV << SLEW_SYSDIV_SHIFT);
 802	v |= (div - 1) << SLEW_SYSDIV_SHIFT;
 803
 804	pic32_syskey_unlock();
 805
 806	writel(v, sclk->slew_reg);
 807
 808	/* wait until BUSY is cleared */
 809	err = readl_poll_timeout_atomic(sclk->slew_reg, v,
 810					!(v & SLEW_BUSY), 1, LOCK_TIMEOUT_US);
 811
 812	spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 813
 814	return err;
 815}
 816
 817static u8 sclk_get_parent(struct clk_hw *hw)
 818{
 819	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 820	u32 i, v;
 821
 822	v = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
 823
 824	if (!sclk->parent_map)
 825		return v;
 826
 827	for (i = 0; i < clk_hw_get_num_parents(hw); i++)
 828		if (sclk->parent_map[i] == v)
 829			return i;
 830	return -EINVAL;
 831}
 832
 833static int sclk_set_parent(struct clk_hw *hw, u8 index)
 834{
 835	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 836	unsigned long flags;
 837	u32 nosc, cosc, v;
 838	int err;
 839
 840	spin_lock_irqsave(&sclk->core->reg_lock, flags);
 841
 842	/* find new_osc */
 843	nosc = sclk->parent_map ? sclk->parent_map[index] : index;
 844
 845	/* set new parent */
 846	v = readl(sclk->mux_reg);
 847	v &= ~(OSC_NEW_MASK << OSC_NEW_SHIFT);
 848	v |= nosc << OSC_NEW_SHIFT;
 849
 850	pic32_syskey_unlock();
 851
 852	writel(v, sclk->mux_reg);
 853
 854	/* initate switch */
 855	writel(OSC_SWEN, PIC32_SET(sclk->mux_reg));
 856	cpu_relax();
 857
 858	/* add nop to flush pipeline (as cpu_clk is in-flux) */
 859	cpu_nop5();
 860
 861	/* wait for SWEN bit to clear */
 862	err = readl_poll_timeout_atomic(sclk->slew_reg, v,
 863					!(v & OSC_SWEN), 1, LOCK_TIMEOUT_US);
 864
 865	spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 866
 867	/*
 868	 * SCLK clock-switching logic might reject a clock switching request
 869	 * if pre-requisites (like new clk_src not present or unstable) are
 870	 * not met.
 871	 * So confirm before claiming success.
 872	 */
 873	cosc = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
 874	if (cosc != nosc) {
 875		pr_err("%s: err, failed to set_parent() to %d, current %d\n",
 876		       clk_hw_get_name(hw), nosc, cosc);
 877		err = -EBUSY;
 878	}
 879
 880	return err;
 881}
 882
 883static void sclk_init(struct clk_hw *hw)
 884{
 885	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 886	unsigned long flags;
 887	u32 v;
 888
 889	/* Maintain reference to this clk, required in spll_clk_set_rate() */
 890	pic32_sclk_hw = hw;
 891
 892	/* apply slew divider on both up and down scaling */
 893	if (sclk->slew_div) {
 894		spin_lock_irqsave(&sclk->core->reg_lock, flags);
 895		v = readl(sclk->slew_reg);
 896		v &= ~(SLEW_DIV << SLEW_DIV_SHIFT);
 897		v |= sclk->slew_div << SLEW_DIV_SHIFT;
 898		v |= SLEW_DOWNEN | SLEW_UPEN;
 899		writel(v, sclk->slew_reg);
 900		spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 901	}
 
 
 902}
 903
 904/* sclk with post-divider */
 905const struct clk_ops pic32_sclk_ops = {
 906	.get_parent	= sclk_get_parent,
 907	.set_parent	= sclk_set_parent,
 908	.round_rate	= sclk_round_rate,
 909	.set_rate	= sclk_set_rate,
 910	.recalc_rate	= sclk_get_rate,
 911	.init		= sclk_init,
 912	.determine_rate = __clk_mux_determine_rate,
 913};
 914
 915/* sclk with no slew and no post-divider */
 916const struct clk_ops pic32_sclk_no_div_ops = {
 917	.get_parent	= sclk_get_parent,
 918	.set_parent	= sclk_set_parent,
 919	.init		= sclk_init,
 920	.determine_rate = __clk_mux_determine_rate,
 921};
 922
 923struct clk *pic32_sys_clk_register(const struct pic32_sys_clk_data *data,
 924				   struct pic32_clk_common *core)
 925{
 926	struct pic32_sys_clk *sclk;
 927	struct clk *clk;
 928
 929	sclk = devm_kzalloc(core->dev, sizeof(*sclk), GFP_KERNEL);
 930	if (!sclk)
 931		return ERR_PTR(-ENOMEM);
 932
 933	sclk->core = core;
 934	sclk->hw.init = &data->init_data;
 935	sclk->mux_reg = data->mux_reg + core->iobase;
 936	sclk->slew_reg = data->slew_reg + core->iobase;
 937	sclk->slew_div = data->slew_div;
 938	sclk->parent_map = data->parent_map;
 939
 940	clk = devm_clk_register(core->dev, &sclk->hw);
 941	if (IS_ERR(clk))
 942		dev_err(core->dev, "%s: clk register failed\n", __func__);
 943
 944	return clk;
 945}
 946
 947/* secondary oscillator */
 948struct pic32_sec_osc {
 949	struct clk_hw hw;
 950	void __iomem *enable_reg;
 951	void __iomem *status_reg;
 952	u32 enable_mask;
 953	u32 status_mask;
 954	unsigned long fixed_rate;
 955	struct pic32_clk_common *core;
 956};
 957
 958#define clkhw_to_sosc(_hw)	container_of(_hw, struct pic32_sec_osc, hw)
 959static int sosc_clk_enable(struct clk_hw *hw)
 960{
 961	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 962	u32 v;
 963
 964	/* enable SOSC */
 965	pic32_syskey_unlock();
 966	writel(sosc->enable_mask, PIC32_SET(sosc->enable_reg));
 967
 968	/* wait till warm-up period expires or ready-status is updated */
 969	return readl_poll_timeout_atomic(sosc->status_reg, v,
 970					 v & sosc->status_mask, 1, 100);
 971}
 972
 973static void sosc_clk_disable(struct clk_hw *hw)
 974{
 975	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 976
 977	pic32_syskey_unlock();
 978	writel(sosc->enable_mask, PIC32_CLR(sosc->enable_reg));
 979}
 980
 981static int sosc_clk_is_enabled(struct clk_hw *hw)
 982{
 983	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 984	u32 enabled, ready;
 985
 986	/* check enabled and ready status */
 987	enabled = readl(sosc->enable_reg) & sosc->enable_mask;
 988	ready = readl(sosc->status_reg) & sosc->status_mask;
 989
 990	return enabled && ready;
 991}
 992
 993static unsigned long sosc_clk_calc_rate(struct clk_hw *hw,
 994					unsigned long parent_rate)
 995{
 996	return clkhw_to_sosc(hw)->fixed_rate;
 997}
 998
 999const struct clk_ops pic32_sosc_ops = {
1000	.enable = sosc_clk_enable,
1001	.disable = sosc_clk_disable,
1002	.is_enabled = sosc_clk_is_enabled,
1003	.recalc_rate = sosc_clk_calc_rate,
1004};
1005
1006struct clk *pic32_sosc_clk_register(const struct pic32_sec_osc_data *data,
1007				    struct pic32_clk_common *core)
1008{
1009	struct pic32_sec_osc *sosc;
1010
1011	sosc = devm_kzalloc(core->dev, sizeof(*sosc), GFP_KERNEL);
1012	if (!sosc)
1013		return ERR_PTR(-ENOMEM);
1014
1015	sosc->core = core;
1016	sosc->hw.init = &data->init_data;
1017	sosc->fixed_rate = data->fixed_rate;
1018	sosc->enable_mask = data->enable_mask;
1019	sosc->status_mask = data->status_mask;
1020	sosc->enable_reg = data->enable_reg + core->iobase;
1021	sosc->status_reg = data->status_reg + core->iobase;
1022
1023	return devm_clk_register(core->dev, &sosc->hw);
1024}
v6.2
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Purna Chandra Mandal,<purna.mandal@microchip.com>
   4 * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
   5 */
   6#include <linux/clk-provider.h>
   7#include <linux/delay.h>
   8#include <linux/device.h>
   9#include <linux/interrupt.h>
  10#include <linux/io.h>
  11#include <linux/iopoll.h>
  12#include <asm/mach-pic32/pic32.h>
  13#include <asm/traps.h>
  14
  15#include "clk-core.h"
  16
  17/* OSCCON Reg fields */
  18#define OSC_CUR_MASK		0x07
  19#define OSC_CUR_SHIFT		12
  20#define OSC_NEW_MASK		0x07
  21#define OSC_NEW_SHIFT		8
  22#define OSC_SWEN		BIT(0)
  23
  24/* SPLLCON Reg fields */
  25#define PLL_RANGE_MASK		0x07
  26#define PLL_RANGE_SHIFT		0
  27#define PLL_ICLK_MASK		0x01
  28#define PLL_ICLK_SHIFT		7
  29#define PLL_IDIV_MASK		0x07
  30#define PLL_IDIV_SHIFT		8
  31#define PLL_ODIV_MASK		0x07
  32#define PLL_ODIV_SHIFT		24
  33#define PLL_MULT_MASK		0x7F
  34#define PLL_MULT_SHIFT		16
  35#define PLL_MULT_MAX		128
  36#define PLL_ODIV_MIN		1
  37#define PLL_ODIV_MAX		5
  38
  39/* Peripheral Bus Clock Reg Fields */
  40#define PB_DIV_MASK		0x7f
  41#define PB_DIV_SHIFT		0
  42#define PB_DIV_READY		BIT(11)
  43#define PB_DIV_ENABLE		BIT(15)
  44#define PB_DIV_MAX		128
  45#define PB_DIV_MIN		0
  46
  47/* Reference Oscillator Control Reg fields */
  48#define REFO_SEL_MASK		0x0f
  49#define REFO_SEL_SHIFT		0
  50#define REFO_ACTIVE		BIT(8)
  51#define REFO_DIVSW_EN		BIT(9)
  52#define REFO_OE			BIT(12)
  53#define REFO_ON			BIT(15)
  54#define REFO_DIV_SHIFT		16
  55#define REFO_DIV_MASK		0x7fff
  56
  57/* Reference Oscillator Trim Register Fields */
  58#define REFO_TRIM_REG		0x10
  59#define REFO_TRIM_MASK		0x1ff
  60#define REFO_TRIM_SHIFT		23
  61#define REFO_TRIM_MAX		511
  62
  63/* Mux Slew Control Register fields */
  64#define SLEW_BUSY		BIT(0)
  65#define SLEW_DOWNEN		BIT(1)
  66#define SLEW_UPEN		BIT(2)
  67#define SLEW_DIV		0x07
  68#define SLEW_DIV_SHIFT		8
  69#define SLEW_SYSDIV		0x0f
  70#define SLEW_SYSDIV_SHIFT	20
  71
  72/* Clock Poll Timeout */
  73#define LOCK_TIMEOUT_US         USEC_PER_MSEC
  74
  75/* SoC specific clock needed during SPLL clock rate switch */
  76static struct clk_hw *pic32_sclk_hw;
  77
  78/* add instruction pipeline delay while CPU clock is in-transition. */
  79#define cpu_nop5()			\
  80do {					\
  81	__asm__ __volatile__("nop");	\
  82	__asm__ __volatile__("nop");	\
  83	__asm__ __volatile__("nop");	\
  84	__asm__ __volatile__("nop");	\
  85	__asm__ __volatile__("nop");	\
  86} while (0)
  87
  88/* Perpheral bus clocks */
  89struct pic32_periph_clk {
  90	struct clk_hw hw;
  91	void __iomem *ctrl_reg;
  92	struct pic32_clk_common *core;
  93};
  94
  95#define clkhw_to_pbclk(_hw)	container_of(_hw, struct pic32_periph_clk, hw)
  96
  97static int pbclk_is_enabled(struct clk_hw *hw)
  98{
  99	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 100
 101	return readl(pb->ctrl_reg) & PB_DIV_ENABLE;
 102}
 103
 104static int pbclk_enable(struct clk_hw *hw)
 105{
 106	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 107
 108	writel(PB_DIV_ENABLE, PIC32_SET(pb->ctrl_reg));
 109	return 0;
 110}
 111
 112static void pbclk_disable(struct clk_hw *hw)
 113{
 114	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 115
 116	writel(PB_DIV_ENABLE, PIC32_CLR(pb->ctrl_reg));
 117}
 118
 119static unsigned long calc_best_divided_rate(unsigned long rate,
 120					    unsigned long parent_rate,
 121					    u32 divider_max,
 122					    u32 divider_min)
 123{
 124	unsigned long divided_rate, divided_rate_down, best_rate;
 125	unsigned long div, div_up;
 126
 127	/* eq. clk_rate = parent_rate / divider.
 128	 *
 129	 * Find best divider to produce closest of target divided rate.
 130	 */
 131	div = parent_rate / rate;
 132	div = clamp_val(div, divider_min, divider_max);
 133	div_up = clamp_val(div + 1, divider_min, divider_max);
 134
 135	divided_rate = parent_rate / div;
 136	divided_rate_down = parent_rate / div_up;
 137	if (abs(rate - divided_rate_down) < abs(rate - divided_rate))
 138		best_rate = divided_rate_down;
 139	else
 140		best_rate = divided_rate;
 141
 142	return best_rate;
 143}
 144
 145static inline u32 pbclk_read_pbdiv(struct pic32_periph_clk *pb)
 146{
 147	return ((readl(pb->ctrl_reg) >> PB_DIV_SHIFT) & PB_DIV_MASK) + 1;
 148}
 149
 150static unsigned long pbclk_recalc_rate(struct clk_hw *hw,
 151				       unsigned long parent_rate)
 152{
 153	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 154
 155	return parent_rate / pbclk_read_pbdiv(pb);
 156}
 157
 158static long pbclk_round_rate(struct clk_hw *hw, unsigned long rate,
 159			     unsigned long *parent_rate)
 160{
 161	return calc_best_divided_rate(rate, *parent_rate,
 162				      PB_DIV_MAX, PB_DIV_MIN);
 163}
 164
 165static int pbclk_set_rate(struct clk_hw *hw, unsigned long rate,
 166			  unsigned long parent_rate)
 167{
 168	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 169	unsigned long flags;
 170	u32 v, div;
 171	int err;
 172
 173	/* check & wait for DIV_READY */
 174	err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
 175				 1, LOCK_TIMEOUT_US);
 176	if (err)
 177		return err;
 178
 179	/* calculate clkdiv and best rate */
 180	div = DIV_ROUND_CLOSEST(parent_rate, rate);
 181
 182	spin_lock_irqsave(&pb->core->reg_lock, flags);
 183
 184	/* apply new div */
 185	v = readl(pb->ctrl_reg);
 186	v &= ~PB_DIV_MASK;
 187	v |= (div - 1);
 188
 189	pic32_syskey_unlock();
 190
 191	writel(v, pb->ctrl_reg);
 192
 193	spin_unlock_irqrestore(&pb->core->reg_lock, flags);
 194
 195	/* wait again for DIV_READY */
 196	err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
 197				 1, LOCK_TIMEOUT_US);
 198	if (err)
 199		return err;
 200
 201	/* confirm that new div is applied correctly */
 202	return (pbclk_read_pbdiv(pb) == div) ? 0 : -EBUSY;
 203}
 204
 205const struct clk_ops pic32_pbclk_ops = {
 206	.enable		= pbclk_enable,
 207	.disable	= pbclk_disable,
 208	.is_enabled	= pbclk_is_enabled,
 209	.recalc_rate	= pbclk_recalc_rate,
 210	.round_rate	= pbclk_round_rate,
 211	.set_rate	= pbclk_set_rate,
 212};
 213
 214struct clk *pic32_periph_clk_register(const struct pic32_periph_clk_data *desc,
 215				      struct pic32_clk_common *core)
 216{
 217	struct pic32_periph_clk *pbclk;
 218	struct clk *clk;
 219
 220	pbclk = devm_kzalloc(core->dev, sizeof(*pbclk), GFP_KERNEL);
 221	if (!pbclk)
 222		return ERR_PTR(-ENOMEM);
 223
 224	pbclk->hw.init = &desc->init_data;
 225	pbclk->core = core;
 226	pbclk->ctrl_reg = desc->ctrl_reg + core->iobase;
 227
 228	clk = devm_clk_register(core->dev, &pbclk->hw);
 229	if (IS_ERR(clk)) {
 230		dev_err(core->dev, "%s: clk_register() failed\n", __func__);
 231		devm_kfree(core->dev, pbclk);
 232	}
 233
 234	return clk;
 235}
 236
 237/* Reference oscillator operations */
 238struct pic32_ref_osc {
 239	struct clk_hw hw;
 240	void __iomem *ctrl_reg;
 241	const u32 *parent_map;
 242	struct pic32_clk_common *core;
 243};
 244
 245#define clkhw_to_refosc(_hw)	container_of(_hw, struct pic32_ref_osc, hw)
 246
 247static int roclk_is_enabled(struct clk_hw *hw)
 248{
 249	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 250
 251	return readl(refo->ctrl_reg) & REFO_ON;
 252}
 253
 254static int roclk_enable(struct clk_hw *hw)
 255{
 256	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 257
 258	writel(REFO_ON | REFO_OE, PIC32_SET(refo->ctrl_reg));
 259	return 0;
 260}
 261
 262static void roclk_disable(struct clk_hw *hw)
 263{
 264	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 265
 266	writel(REFO_ON | REFO_OE, PIC32_CLR(refo->ctrl_reg));
 267}
 268
 269static int roclk_init(struct clk_hw *hw)
 270{
 271	/* initialize clock in disabled state */
 272	roclk_disable(hw);
 273
 274	return 0;
 275}
 276
 277static u8 roclk_get_parent(struct clk_hw *hw)
 278{
 279	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 280	u32 v, i;
 281
 282	v = (readl(refo->ctrl_reg) >> REFO_SEL_SHIFT) & REFO_SEL_MASK;
 283
 284	if (!refo->parent_map)
 285		return v;
 286
 287	for (i = 0; i < clk_hw_get_num_parents(hw); i++)
 288		if (refo->parent_map[i] == v)
 289			return i;
 290
 291	return -EINVAL;
 292}
 293
 294static unsigned long roclk_calc_rate(unsigned long parent_rate,
 295				     u32 rodiv, u32 rotrim)
 296{
 297	u64 rate64;
 298
 299	/* fout = fin / [2 * {div + (trim / 512)}]
 300	 *	= fin * 512 / [1024 * div + 2 * trim]
 301	 *	= fin * 256 / (512 * div + trim)
 302	 *	= (fin << 8) / ((div << 9) + trim)
 303	 */
 304	if (rotrim) {
 305		rodiv = (rodiv << 9) + rotrim;
 306		rate64 = parent_rate;
 307		rate64 <<= 8;
 308		do_div(rate64, rodiv);
 309	} else if (rodiv) {
 310		rate64 = parent_rate / (rodiv << 1);
 311	} else {
 312		rate64 = parent_rate;
 313	}
 314	return rate64;
 315}
 316
 317static void roclk_calc_div_trim(unsigned long rate,
 318				unsigned long parent_rate,
 319				u32 *rodiv_p, u32 *rotrim_p)
 320{
 321	u32 div, rotrim, rodiv;
 322	u64 frac;
 323
 324	/* Find integer approximation of floating-point arithmetic.
 325	 *      fout = fin / [2 * {rodiv + (rotrim / 512)}] ... (1)
 326	 * i.e. fout = fin / 2 * DIV
 327	 *      whereas DIV = rodiv + (rotrim / 512)
 328	 *
 329	 * Since kernel does not perform floating-point arithmatic so
 330	 * (rotrim/512) will be zero. And DIV & rodiv will result same.
 331	 *
 332	 * ie. fout = (fin * 256) / [(512 * rodiv) + rotrim]  ... from (1)
 333	 * ie. rotrim = ((fin * 256) / fout) - (512 * DIV)
 334	 */
 335	if (parent_rate <= rate) {
 336		div = 0;
 337		frac = 0;
 338		rodiv = 0;
 339		rotrim = 0;
 340	} else {
 341		div = parent_rate / (rate << 1);
 342		frac = parent_rate;
 343		frac <<= 8;
 344		do_div(frac, rate);
 345		frac -= (u64)(div << 9);
 346
 347		rodiv = (div > REFO_DIV_MASK) ? REFO_DIV_MASK : div;
 348		rotrim = (frac >= REFO_TRIM_MAX) ? REFO_TRIM_MAX : frac;
 349	}
 350
 351	if (rodiv_p)
 352		*rodiv_p = rodiv;
 353
 354	if (rotrim_p)
 355		*rotrim_p = rotrim;
 356}
 357
 358static unsigned long roclk_recalc_rate(struct clk_hw *hw,
 359				       unsigned long parent_rate)
 360{
 361	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 362	u32 v, rodiv, rotrim;
 363
 364	/* get rodiv */
 365	v = readl(refo->ctrl_reg);
 366	rodiv = (v >> REFO_DIV_SHIFT) & REFO_DIV_MASK;
 367
 368	/* get trim */
 369	v = readl(refo->ctrl_reg + REFO_TRIM_REG);
 370	rotrim = (v >> REFO_TRIM_SHIFT) & REFO_TRIM_MASK;
 371
 372	return roclk_calc_rate(parent_rate, rodiv, rotrim);
 373}
 374
 375static long roclk_round_rate(struct clk_hw *hw, unsigned long rate,
 376			     unsigned long *parent_rate)
 377{
 378	u32 rotrim, rodiv;
 379
 380	/* calculate dividers for new rate */
 381	roclk_calc_div_trim(rate, *parent_rate, &rodiv, &rotrim);
 382
 383	/* caclulate new rate (rounding) based on new rodiv & rotrim */
 384	return roclk_calc_rate(*parent_rate, rodiv, rotrim);
 385}
 386
 387static int roclk_determine_rate(struct clk_hw *hw,
 388				struct clk_rate_request *req)
 389{
 390	struct clk_hw *parent_clk, *best_parent_clk = NULL;
 391	unsigned int i, delta, best_delta = -1;
 392	unsigned long parent_rate, best_parent_rate = 0;
 393	unsigned long best = 0, nearest_rate;
 394
 395	/* find a parent which can generate nearest clkrate >= rate */
 396	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
 397		/* get parent */
 398		parent_clk = clk_hw_get_parent_by_index(hw, i);
 399		if (!parent_clk)
 400			continue;
 401
 402		/* skip if parent runs slower than target rate */
 403		parent_rate = clk_hw_get_rate(parent_clk);
 404		if (req->rate > parent_rate)
 405			continue;
 406
 407		nearest_rate = roclk_round_rate(hw, req->rate, &parent_rate);
 408		delta = abs(nearest_rate - req->rate);
 409		if ((nearest_rate >= req->rate) && (delta < best_delta)) {
 410			best_parent_clk = parent_clk;
 411			best_parent_rate = parent_rate;
 412			best = nearest_rate;
 413			best_delta = delta;
 414
 415			if (delta == 0)
 416				break;
 417		}
 418	}
 419
 420	/* if no match found, retain old rate */
 421	if (!best_parent_clk) {
 422		pr_err("%s:%s, no parent found for rate %lu.\n",
 423		       __func__, clk_hw_get_name(hw), req->rate);
 424		return clk_hw_get_rate(hw);
 425	}
 426
 427	pr_debug("%s,rate %lu, best_parent(%s, %lu), best %lu, delta %d\n",
 428		 clk_hw_get_name(hw), req->rate,
 429		 clk_hw_get_name(best_parent_clk), best_parent_rate,
 430		 best, best_delta);
 431
 432	if (req->best_parent_rate)
 433		req->best_parent_rate = best_parent_rate;
 434
 435	if (req->best_parent_hw)
 436		req->best_parent_hw = best_parent_clk;
 437
 438	return best;
 439}
 440
 441static int roclk_set_parent(struct clk_hw *hw, u8 index)
 442{
 443	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 444	unsigned long flags;
 445	u32 v;
 446	int err;
 447
 448	if (refo->parent_map)
 449		index = refo->parent_map[index];
 450
 451	/* wait until ACTIVE bit is zero or timeout */
 452	err = readl_poll_timeout(refo->ctrl_reg, v, !(v & REFO_ACTIVE),
 453				 1, LOCK_TIMEOUT_US);
 454	if (err) {
 455		pr_err("%s: poll failed, clk active\n", clk_hw_get_name(hw));
 456		return err;
 457	}
 458
 459	spin_lock_irqsave(&refo->core->reg_lock, flags);
 460
 461	pic32_syskey_unlock();
 462
 463	/* calculate & apply new */
 464	v = readl(refo->ctrl_reg);
 465	v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
 466	v |= index << REFO_SEL_SHIFT;
 467
 468	writel(v, refo->ctrl_reg);
 469
 470	spin_unlock_irqrestore(&refo->core->reg_lock, flags);
 471
 472	return 0;
 473}
 474
 475static int roclk_set_rate_and_parent(struct clk_hw *hw,
 476				     unsigned long rate,
 477				     unsigned long parent_rate,
 478				     u8 index)
 479{
 480	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 481	unsigned long flags;
 482	u32 trim, rodiv, v;
 483	int err;
 484
 485	/* calculate new rodiv & rotrim for new rate */
 486	roclk_calc_div_trim(rate, parent_rate, &rodiv, &trim);
 487
 488	pr_debug("parent_rate = %lu, rate = %lu, div = %d, trim = %d\n",
 489		 parent_rate, rate, rodiv, trim);
 490
 491	/* wait till source change is active */
 492	err = readl_poll_timeout(refo->ctrl_reg, v,
 493				 !(v & (REFO_ACTIVE | REFO_DIVSW_EN)),
 494				 1, LOCK_TIMEOUT_US);
 495	if (err) {
 496		pr_err("%s: poll timedout, clock is still active\n", __func__);
 497		return err;
 498	}
 499
 500	spin_lock_irqsave(&refo->core->reg_lock, flags);
 501	v = readl(refo->ctrl_reg);
 502
 503	pic32_syskey_unlock();
 504
 505	/* apply parent, if required */
 506	if (refo->parent_map)
 507		index = refo->parent_map[index];
 508
 509	v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
 510	v |= index << REFO_SEL_SHIFT;
 511
 512	/* apply RODIV */
 513	v &= ~(REFO_DIV_MASK << REFO_DIV_SHIFT);
 514	v |= rodiv << REFO_DIV_SHIFT;
 515	writel(v, refo->ctrl_reg);
 516
 517	/* apply ROTRIM */
 518	v = readl(refo->ctrl_reg + REFO_TRIM_REG);
 519	v &= ~(REFO_TRIM_MASK << REFO_TRIM_SHIFT);
 520	v |= trim << REFO_TRIM_SHIFT;
 521	writel(v, refo->ctrl_reg + REFO_TRIM_REG);
 522
 523	/* enable & activate divider switching */
 524	writel(REFO_ON | REFO_DIVSW_EN, PIC32_SET(refo->ctrl_reg));
 525
 526	/* wait till divswen is in-progress */
 527	err = readl_poll_timeout_atomic(refo->ctrl_reg, v, !(v & REFO_DIVSW_EN),
 528					1, LOCK_TIMEOUT_US);
 529	/* leave the clk gated as it was */
 530	writel(REFO_ON, PIC32_CLR(refo->ctrl_reg));
 531
 532	spin_unlock_irqrestore(&refo->core->reg_lock, flags);
 533
 534	return err;
 535}
 536
 537static int roclk_set_rate(struct clk_hw *hw, unsigned long rate,
 538			  unsigned long parent_rate)
 539{
 540	u8 index = roclk_get_parent(hw);
 541
 542	return roclk_set_rate_and_parent(hw, rate, parent_rate, index);
 543}
 544
 545const struct clk_ops pic32_roclk_ops = {
 546	.enable			= roclk_enable,
 547	.disable		= roclk_disable,
 548	.is_enabled		= roclk_is_enabled,
 549	.get_parent		= roclk_get_parent,
 550	.set_parent		= roclk_set_parent,
 551	.determine_rate		= roclk_determine_rate,
 552	.recalc_rate		= roclk_recalc_rate,
 553	.set_rate_and_parent	= roclk_set_rate_and_parent,
 554	.set_rate		= roclk_set_rate,
 555	.init			= roclk_init,
 556};
 557
 558struct clk *pic32_refo_clk_register(const struct pic32_ref_osc_data *data,
 559				    struct pic32_clk_common *core)
 560{
 561	struct pic32_ref_osc *refo;
 562	struct clk *clk;
 563
 564	refo = devm_kzalloc(core->dev, sizeof(*refo), GFP_KERNEL);
 565	if (!refo)
 566		return ERR_PTR(-ENOMEM);
 567
 568	refo->core = core;
 569	refo->hw.init = &data->init_data;
 570	refo->ctrl_reg = data->ctrl_reg + core->iobase;
 571	refo->parent_map = data->parent_map;
 572
 573	clk = devm_clk_register(core->dev, &refo->hw);
 574	if (IS_ERR(clk))
 575		dev_err(core->dev, "%s: clk_register() failed\n", __func__);
 576
 577	return clk;
 578}
 579
 580struct pic32_sys_pll {
 581	struct clk_hw hw;
 582	void __iomem *ctrl_reg;
 583	void __iomem *status_reg;
 584	u32 lock_mask;
 585	u32 idiv; /* PLL iclk divider, treated fixed */
 586	struct pic32_clk_common *core;
 587};
 588
 589#define clkhw_to_spll(_hw)	container_of(_hw, struct pic32_sys_pll, hw)
 590
 591static inline u32 spll_odiv_to_divider(u32 odiv)
 592{
 593	odiv = clamp_val(odiv, PLL_ODIV_MIN, PLL_ODIV_MAX);
 594
 595	return 1 << odiv;
 596}
 597
 598static unsigned long spll_calc_mult_div(struct pic32_sys_pll *pll,
 599					unsigned long rate,
 600					unsigned long parent_rate,
 601					u32 *mult_p, u32 *odiv_p)
 602{
 603	u32 mul, div, best_mul = 1, best_div = 1;
 604	unsigned long new_rate, best_rate = rate;
 605	unsigned int best_delta = -1, delta, match_found = 0;
 606	u64 rate64;
 607
 608	parent_rate /= pll->idiv;
 609
 610	for (mul = 1; mul <= PLL_MULT_MAX; mul++) {
 611		for (div = PLL_ODIV_MIN; div <= PLL_ODIV_MAX; div++) {
 612			rate64 = parent_rate;
 613			rate64 *= mul;
 614			do_div(rate64, 1 << div);
 615			new_rate = rate64;
 616			delta = abs(rate - new_rate);
 617			if ((new_rate >= rate) && (delta < best_delta)) {
 618				best_delta = delta;
 619				best_rate = new_rate;
 620				best_mul = mul;
 621				best_div = div;
 622				match_found = 1;
 623			}
 624		}
 625	}
 626
 627	if (!match_found) {
 628		pr_warn("spll: no match found\n");
 629		return 0;
 630	}
 631
 632	pr_debug("rate %lu, par_rate %lu/mult %u, div %u, best_rate %lu\n",
 633		 rate, parent_rate, best_mul, best_div, best_rate);
 634
 635	if (mult_p)
 636		*mult_p = best_mul - 1;
 637
 638	if (odiv_p)
 639		*odiv_p = best_div;
 640
 641	return best_rate;
 642}
 643
 644static unsigned long spll_clk_recalc_rate(struct clk_hw *hw,
 645					  unsigned long parent_rate)
 646{
 647	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 648	unsigned long pll_in_rate;
 649	u32 mult, odiv, div, v;
 650	u64 rate64;
 651
 652	v = readl(pll->ctrl_reg);
 653	odiv = ((v >> PLL_ODIV_SHIFT) & PLL_ODIV_MASK);
 654	mult = ((v >> PLL_MULT_SHIFT) & PLL_MULT_MASK) + 1;
 655	div = spll_odiv_to_divider(odiv);
 656
 657	/* pll_in_rate = parent_rate / idiv
 658	 * pll_out_rate = pll_in_rate * mult / div;
 659	 */
 660	pll_in_rate = parent_rate / pll->idiv;
 661	rate64 = pll_in_rate;
 662	rate64 *= mult;
 663	do_div(rate64, div);
 664
 665	return rate64;
 666}
 667
 668static long spll_clk_round_rate(struct clk_hw *hw, unsigned long rate,
 669				unsigned long *parent_rate)
 670{
 671	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 672
 673	return spll_calc_mult_div(pll, rate, *parent_rate, NULL, NULL);
 674}
 675
 676static int spll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 677			     unsigned long parent_rate)
 678{
 679	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 680	unsigned long ret, flags;
 681	u32 mult, odiv, v;
 682	int err;
 683
 684	ret = spll_calc_mult_div(pll, rate, parent_rate, &mult, &odiv);
 685	if (!ret)
 686		return -EINVAL;
 687
 688	/*
 689	 * We can't change SPLL counters when it is in-active use
 690	 * by SYSCLK. So check before applying new counters/rate.
 691	 */
 692
 693	/* Is spll_clk active parent of sys_clk ? */
 694	if (unlikely(clk_hw_get_parent(pic32_sclk_hw) == hw)) {
 695		pr_err("%s: failed, clk in-use\n", __func__);
 696		return -EBUSY;
 697	}
 698
 699	spin_lock_irqsave(&pll->core->reg_lock, flags);
 700
 701	/* apply new multiplier & divisor */
 702	v = readl(pll->ctrl_reg);
 703	v &= ~(PLL_MULT_MASK << PLL_MULT_SHIFT);
 704	v &= ~(PLL_ODIV_MASK << PLL_ODIV_SHIFT);
 705	v |= (mult << PLL_MULT_SHIFT) | (odiv << PLL_ODIV_SHIFT);
 706
 707	/* sys unlock before write */
 708	pic32_syskey_unlock();
 709
 710	writel(v, pll->ctrl_reg);
 711	cpu_relax();
 712
 713	/* insert few nops (5-stage) to ensure CPU does not hang */
 714	cpu_nop5();
 715	cpu_nop5();
 716
 717	/* Wait until PLL is locked (maximum 100 usecs). */
 718	err = readl_poll_timeout_atomic(pll->status_reg, v,
 719					v & pll->lock_mask, 1, 100);
 720	spin_unlock_irqrestore(&pll->core->reg_lock, flags);
 721
 722	return err;
 723}
 724
 725/* SPLL clock operation */
 726const struct clk_ops pic32_spll_ops = {
 727	.recalc_rate	= spll_clk_recalc_rate,
 728	.round_rate	= spll_clk_round_rate,
 729	.set_rate	= spll_clk_set_rate,
 730};
 731
 732struct clk *pic32_spll_clk_register(const struct pic32_sys_pll_data *data,
 733				    struct pic32_clk_common *core)
 734{
 735	struct pic32_sys_pll *spll;
 736	struct clk *clk;
 737
 738	spll = devm_kzalloc(core->dev, sizeof(*spll), GFP_KERNEL);
 739	if (!spll)
 740		return ERR_PTR(-ENOMEM);
 741
 742	spll->core = core;
 743	spll->hw.init = &data->init_data;
 744	spll->ctrl_reg = data->ctrl_reg + core->iobase;
 745	spll->status_reg = data->status_reg + core->iobase;
 746	spll->lock_mask = data->lock_mask;
 747
 748	/* cache PLL idiv; PLL driver uses it as constant.*/
 749	spll->idiv = (readl(spll->ctrl_reg) >> PLL_IDIV_SHIFT) & PLL_IDIV_MASK;
 750	spll->idiv += 1;
 751
 752	clk = devm_clk_register(core->dev, &spll->hw);
 753	if (IS_ERR(clk))
 754		dev_err(core->dev, "sys_pll: clk_register() failed\n");
 755
 756	return clk;
 757}
 758
 759/* System mux clock(aka SCLK) */
 760
 761struct pic32_sys_clk {
 762	struct clk_hw hw;
 763	void __iomem *mux_reg;
 764	void __iomem *slew_reg;
 765	u32 slew_div;
 766	const u32 *parent_map;
 767	struct pic32_clk_common *core;
 768};
 769
 770#define clkhw_to_sys_clk(_hw)	container_of(_hw, struct pic32_sys_clk, hw)
 771
 772static unsigned long sclk_get_rate(struct clk_hw *hw, unsigned long parent_rate)
 773{
 774	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 775	u32 div;
 776
 777	div = (readl(sclk->slew_reg) >> SLEW_SYSDIV_SHIFT) & SLEW_SYSDIV;
 778	div += 1; /* sys-div to divider */
 779
 780	return parent_rate / div;
 781}
 782
 783static long sclk_round_rate(struct clk_hw *hw, unsigned long rate,
 784			    unsigned long *parent_rate)
 785{
 786	return calc_best_divided_rate(rate, *parent_rate, SLEW_SYSDIV, 1);
 787}
 788
 789static int sclk_set_rate(struct clk_hw *hw,
 790			 unsigned long rate, unsigned long parent_rate)
 791{
 792	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 793	unsigned long flags;
 794	u32 v, div;
 795	int err;
 796
 797	div = parent_rate / rate;
 798
 799	spin_lock_irqsave(&sclk->core->reg_lock, flags);
 800
 801	/* apply new div */
 802	v = readl(sclk->slew_reg);
 803	v &= ~(SLEW_SYSDIV << SLEW_SYSDIV_SHIFT);
 804	v |= (div - 1) << SLEW_SYSDIV_SHIFT;
 805
 806	pic32_syskey_unlock();
 807
 808	writel(v, sclk->slew_reg);
 809
 810	/* wait until BUSY is cleared */
 811	err = readl_poll_timeout_atomic(sclk->slew_reg, v,
 812					!(v & SLEW_BUSY), 1, LOCK_TIMEOUT_US);
 813
 814	spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 815
 816	return err;
 817}
 818
 819static u8 sclk_get_parent(struct clk_hw *hw)
 820{
 821	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 822	u32 i, v;
 823
 824	v = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
 825
 826	if (!sclk->parent_map)
 827		return v;
 828
 829	for (i = 0; i < clk_hw_get_num_parents(hw); i++)
 830		if (sclk->parent_map[i] == v)
 831			return i;
 832	return -EINVAL;
 833}
 834
 835static int sclk_set_parent(struct clk_hw *hw, u8 index)
 836{
 837	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 838	unsigned long flags;
 839	u32 nosc, cosc, v;
 840	int err;
 841
 842	spin_lock_irqsave(&sclk->core->reg_lock, flags);
 843
 844	/* find new_osc */
 845	nosc = sclk->parent_map ? sclk->parent_map[index] : index;
 846
 847	/* set new parent */
 848	v = readl(sclk->mux_reg);
 849	v &= ~(OSC_NEW_MASK << OSC_NEW_SHIFT);
 850	v |= nosc << OSC_NEW_SHIFT;
 851
 852	pic32_syskey_unlock();
 853
 854	writel(v, sclk->mux_reg);
 855
 856	/* initate switch */
 857	writel(OSC_SWEN, PIC32_SET(sclk->mux_reg));
 858	cpu_relax();
 859
 860	/* add nop to flush pipeline (as cpu_clk is in-flux) */
 861	cpu_nop5();
 862
 863	/* wait for SWEN bit to clear */
 864	err = readl_poll_timeout_atomic(sclk->slew_reg, v,
 865					!(v & OSC_SWEN), 1, LOCK_TIMEOUT_US);
 866
 867	spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 868
 869	/*
 870	 * SCLK clock-switching logic might reject a clock switching request
 871	 * if pre-requisites (like new clk_src not present or unstable) are
 872	 * not met.
 873	 * So confirm before claiming success.
 874	 */
 875	cosc = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
 876	if (cosc != nosc) {
 877		pr_err("%s: err, failed to set_parent() to %d, current %d\n",
 878		       clk_hw_get_name(hw), nosc, cosc);
 879		err = -EBUSY;
 880	}
 881
 882	return err;
 883}
 884
 885static int sclk_init(struct clk_hw *hw)
 886{
 887	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 888	unsigned long flags;
 889	u32 v;
 890
 891	/* Maintain reference to this clk, required in spll_clk_set_rate() */
 892	pic32_sclk_hw = hw;
 893
 894	/* apply slew divider on both up and down scaling */
 895	if (sclk->slew_div) {
 896		spin_lock_irqsave(&sclk->core->reg_lock, flags);
 897		v = readl(sclk->slew_reg);
 898		v &= ~(SLEW_DIV << SLEW_DIV_SHIFT);
 899		v |= sclk->slew_div << SLEW_DIV_SHIFT;
 900		v |= SLEW_DOWNEN | SLEW_UPEN;
 901		writel(v, sclk->slew_reg);
 902		spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 903	}
 904
 905	return 0;
 906}
 907
 908/* sclk with post-divider */
 909const struct clk_ops pic32_sclk_ops = {
 910	.get_parent	= sclk_get_parent,
 911	.set_parent	= sclk_set_parent,
 912	.round_rate	= sclk_round_rate,
 913	.set_rate	= sclk_set_rate,
 914	.recalc_rate	= sclk_get_rate,
 915	.init		= sclk_init,
 916	.determine_rate = __clk_mux_determine_rate,
 917};
 918
 919/* sclk with no slew and no post-divider */
 920const struct clk_ops pic32_sclk_no_div_ops = {
 921	.get_parent	= sclk_get_parent,
 922	.set_parent	= sclk_set_parent,
 923	.init		= sclk_init,
 924	.determine_rate = __clk_mux_determine_rate,
 925};
 926
 927struct clk *pic32_sys_clk_register(const struct pic32_sys_clk_data *data,
 928				   struct pic32_clk_common *core)
 929{
 930	struct pic32_sys_clk *sclk;
 931	struct clk *clk;
 932
 933	sclk = devm_kzalloc(core->dev, sizeof(*sclk), GFP_KERNEL);
 934	if (!sclk)
 935		return ERR_PTR(-ENOMEM);
 936
 937	sclk->core = core;
 938	sclk->hw.init = &data->init_data;
 939	sclk->mux_reg = data->mux_reg + core->iobase;
 940	sclk->slew_reg = data->slew_reg + core->iobase;
 941	sclk->slew_div = data->slew_div;
 942	sclk->parent_map = data->parent_map;
 943
 944	clk = devm_clk_register(core->dev, &sclk->hw);
 945	if (IS_ERR(clk))
 946		dev_err(core->dev, "%s: clk register failed\n", __func__);
 947
 948	return clk;
 949}
 950
 951/* secondary oscillator */
 952struct pic32_sec_osc {
 953	struct clk_hw hw;
 954	void __iomem *enable_reg;
 955	void __iomem *status_reg;
 956	u32 enable_mask;
 957	u32 status_mask;
 958	unsigned long fixed_rate;
 959	struct pic32_clk_common *core;
 960};
 961
 962#define clkhw_to_sosc(_hw)	container_of(_hw, struct pic32_sec_osc, hw)
 963static int sosc_clk_enable(struct clk_hw *hw)
 964{
 965	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 966	u32 v;
 967
 968	/* enable SOSC */
 969	pic32_syskey_unlock();
 970	writel(sosc->enable_mask, PIC32_SET(sosc->enable_reg));
 971
 972	/* wait till warm-up period expires or ready-status is updated */
 973	return readl_poll_timeout_atomic(sosc->status_reg, v,
 974					 v & sosc->status_mask, 1, 100);
 975}
 976
 977static void sosc_clk_disable(struct clk_hw *hw)
 978{
 979	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 980
 981	pic32_syskey_unlock();
 982	writel(sosc->enable_mask, PIC32_CLR(sosc->enable_reg));
 983}
 984
 985static int sosc_clk_is_enabled(struct clk_hw *hw)
 986{
 987	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 988	u32 enabled, ready;
 989
 990	/* check enabled and ready status */
 991	enabled = readl(sosc->enable_reg) & sosc->enable_mask;
 992	ready = readl(sosc->status_reg) & sosc->status_mask;
 993
 994	return enabled && ready;
 995}
 996
 997static unsigned long sosc_clk_calc_rate(struct clk_hw *hw,
 998					unsigned long parent_rate)
 999{
1000	return clkhw_to_sosc(hw)->fixed_rate;
1001}
1002
1003const struct clk_ops pic32_sosc_ops = {
1004	.enable = sosc_clk_enable,
1005	.disable = sosc_clk_disable,
1006	.is_enabled = sosc_clk_is_enabled,
1007	.recalc_rate = sosc_clk_calc_rate,
1008};
1009
1010struct clk *pic32_sosc_clk_register(const struct pic32_sec_osc_data *data,
1011				    struct pic32_clk_common *core)
1012{
1013	struct pic32_sec_osc *sosc;
1014
1015	sosc = devm_kzalloc(core->dev, sizeof(*sosc), GFP_KERNEL);
1016	if (!sosc)
1017		return ERR_PTR(-ENOMEM);
1018
1019	sosc->core = core;
1020	sosc->hw.init = &data->init_data;
1021	sosc->fixed_rate = data->fixed_rate;
1022	sosc->enable_mask = data->enable_mask;
1023	sosc->status_mask = data->status_mask;
1024	sosc->enable_reg = data->enable_reg + core->iobase;
1025	sosc->status_reg = data->status_reg + core->iobase;
1026
1027	return devm_clk_register(core->dev, &sosc->hw);
1028}