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v5.14.15
   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}
v4.10.11
 
   1/*
   2 * Purna Chandra Mandal,<purna.mandal@microchip.com>
   3 * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
   4 *
   5 * This program is free software; you can distribute it and/or modify it
   6 * under the terms of the GNU General Public License (Version 2) as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 * for more details.
  13 */
  14#include <linux/clk-provider.h>
  15#include <linux/delay.h>
  16#include <linux/device.h>
  17#include <linux/interrupt.h>
 
  18#include <linux/iopoll.h>
  19#include <asm/mach-pic32/pic32.h>
  20#include <asm/traps.h>
  21
  22#include "clk-core.h"
  23
  24/* OSCCON Reg fields */
  25#define OSC_CUR_MASK		0x07
  26#define OSC_CUR_SHIFT		12
  27#define OSC_NEW_MASK		0x07
  28#define OSC_NEW_SHIFT		8
  29#define OSC_SWEN		BIT(0)
  30
  31/* SPLLCON Reg fields */
  32#define PLL_RANGE_MASK		0x07
  33#define PLL_RANGE_SHIFT		0
  34#define PLL_ICLK_MASK		0x01
  35#define PLL_ICLK_SHIFT		7
  36#define PLL_IDIV_MASK		0x07
  37#define PLL_IDIV_SHIFT		8
  38#define PLL_ODIV_MASK		0x07
  39#define PLL_ODIV_SHIFT		24
  40#define PLL_MULT_MASK		0x7F
  41#define PLL_MULT_SHIFT		16
  42#define PLL_MULT_MAX		128
  43#define PLL_ODIV_MIN		1
  44#define PLL_ODIV_MAX		5
  45
  46/* Peripheral Bus Clock Reg Fields */
  47#define PB_DIV_MASK		0x7f
  48#define PB_DIV_SHIFT		0
  49#define PB_DIV_READY		BIT(11)
  50#define PB_DIV_ENABLE		BIT(15)
  51#define PB_DIV_MAX		128
  52#define PB_DIV_MIN		0
  53
  54/* Reference Oscillator Control Reg fields */
  55#define REFO_SEL_MASK		0x0f
  56#define REFO_SEL_SHIFT		0
  57#define REFO_ACTIVE		BIT(8)
  58#define REFO_DIVSW_EN		BIT(9)
  59#define REFO_OE			BIT(12)
  60#define REFO_ON			BIT(15)
  61#define REFO_DIV_SHIFT		16
  62#define REFO_DIV_MASK		0x7fff
  63
  64/* Reference Oscillator Trim Register Fields */
  65#define REFO_TRIM_REG		0x10
  66#define REFO_TRIM_MASK		0x1ff
  67#define REFO_TRIM_SHIFT		23
  68#define REFO_TRIM_MAX		511
  69
  70/* Mux Slew Control Register fields */
  71#define SLEW_BUSY		BIT(0)
  72#define SLEW_DOWNEN		BIT(1)
  73#define SLEW_UPEN		BIT(2)
  74#define SLEW_DIV		0x07
  75#define SLEW_DIV_SHIFT		8
  76#define SLEW_SYSDIV		0x0f
  77#define SLEW_SYSDIV_SHIFT	20
  78
  79/* Clock Poll Timeout */
  80#define LOCK_TIMEOUT_US         USEC_PER_MSEC
  81
  82/* SoC specific clock needed during SPLL clock rate switch */
  83static struct clk_hw *pic32_sclk_hw;
  84
  85/* add instruction pipeline delay while CPU clock is in-transition. */
  86#define cpu_nop5()			\
  87do {					\
  88	__asm__ __volatile__("nop");	\
  89	__asm__ __volatile__("nop");	\
  90	__asm__ __volatile__("nop");	\
  91	__asm__ __volatile__("nop");	\
  92	__asm__ __volatile__("nop");	\
  93} while (0)
  94
  95/* Perpheral bus clocks */
  96struct pic32_periph_clk {
  97	struct clk_hw hw;
  98	void __iomem *ctrl_reg;
  99	struct pic32_clk_common *core;
 100};
 101
 102#define clkhw_to_pbclk(_hw)	container_of(_hw, struct pic32_periph_clk, hw)
 103
 104static int pbclk_is_enabled(struct clk_hw *hw)
 105{
 106	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 107
 108	return readl(pb->ctrl_reg) & PB_DIV_ENABLE;
 109}
 110
 111static int pbclk_enable(struct clk_hw *hw)
 112{
 113	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 114
 115	writel(PB_DIV_ENABLE, PIC32_SET(pb->ctrl_reg));
 116	return 0;
 117}
 118
 119static void pbclk_disable(struct clk_hw *hw)
 120{
 121	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 122
 123	writel(PB_DIV_ENABLE, PIC32_CLR(pb->ctrl_reg));
 124}
 125
 126static unsigned long calc_best_divided_rate(unsigned long rate,
 127					    unsigned long parent_rate,
 128					    u32 divider_max,
 129					    u32 divider_min)
 130{
 131	unsigned long divided_rate, divided_rate_down, best_rate;
 132	unsigned long div, div_up;
 133
 134	/* eq. clk_rate = parent_rate / divider.
 135	 *
 136	 * Find best divider to produce closest of target divided rate.
 137	 */
 138	div = parent_rate / rate;
 139	div = clamp_val(div, divider_min, divider_max);
 140	div_up = clamp_val(div + 1, divider_min, divider_max);
 141
 142	divided_rate = parent_rate / div;
 143	divided_rate_down = parent_rate / div_up;
 144	if (abs(rate - divided_rate_down) < abs(rate - divided_rate))
 145		best_rate = divided_rate_down;
 146	else
 147		best_rate = divided_rate;
 148
 149	return best_rate;
 150}
 151
 152static inline u32 pbclk_read_pbdiv(struct pic32_periph_clk *pb)
 153{
 154	return ((readl(pb->ctrl_reg) >> PB_DIV_SHIFT) & PB_DIV_MASK) + 1;
 155}
 156
 157static unsigned long pbclk_recalc_rate(struct clk_hw *hw,
 158				       unsigned long parent_rate)
 159{
 160	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 161
 162	return parent_rate / pbclk_read_pbdiv(pb);
 163}
 164
 165static long pbclk_round_rate(struct clk_hw *hw, unsigned long rate,
 166			     unsigned long *parent_rate)
 167{
 168	return calc_best_divided_rate(rate, *parent_rate,
 169				      PB_DIV_MAX, PB_DIV_MIN);
 170}
 171
 172static int pbclk_set_rate(struct clk_hw *hw, unsigned long rate,
 173			  unsigned long parent_rate)
 174{
 175	struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
 176	unsigned long flags;
 177	u32 v, div;
 178	int err;
 179
 180	/* check & wait for DIV_READY */
 181	err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
 182				 1, LOCK_TIMEOUT_US);
 183	if (err)
 184		return err;
 185
 186	/* calculate clkdiv and best rate */
 187	div = DIV_ROUND_CLOSEST(parent_rate, rate);
 188
 189	spin_lock_irqsave(&pb->core->reg_lock, flags);
 190
 191	/* apply new div */
 192	v = readl(pb->ctrl_reg);
 193	v &= ~PB_DIV_MASK;
 194	v |= (div - 1);
 195
 196	pic32_syskey_unlock();
 197
 198	writel(v, pb->ctrl_reg);
 199
 200	spin_unlock_irqrestore(&pb->core->reg_lock, flags);
 201
 202	/* wait again for DIV_READY */
 203	err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
 204				 1, LOCK_TIMEOUT_US);
 205	if (err)
 206		return err;
 207
 208	/* confirm that new div is applied correctly */
 209	return (pbclk_read_pbdiv(pb) == div) ? 0 : -EBUSY;
 210}
 211
 212const struct clk_ops pic32_pbclk_ops = {
 213	.enable		= pbclk_enable,
 214	.disable	= pbclk_disable,
 215	.is_enabled	= pbclk_is_enabled,
 216	.recalc_rate	= pbclk_recalc_rate,
 217	.round_rate	= pbclk_round_rate,
 218	.set_rate	= pbclk_set_rate,
 219};
 220
 221struct clk *pic32_periph_clk_register(const struct pic32_periph_clk_data *desc,
 222				      struct pic32_clk_common *core)
 223{
 224	struct pic32_periph_clk *pbclk;
 225	struct clk *clk;
 226
 227	pbclk = devm_kzalloc(core->dev, sizeof(*pbclk), GFP_KERNEL);
 228	if (!pbclk)
 229		return ERR_PTR(-ENOMEM);
 230
 231	pbclk->hw.init = &desc->init_data;
 232	pbclk->core = core;
 233	pbclk->ctrl_reg = desc->ctrl_reg + core->iobase;
 234
 235	clk = devm_clk_register(core->dev, &pbclk->hw);
 236	if (IS_ERR(clk)) {
 237		dev_err(core->dev, "%s: clk_register() failed\n", __func__);
 238		devm_kfree(core->dev, pbclk);
 239	}
 240
 241	return clk;
 242}
 243
 244/* Reference oscillator operations */
 245struct pic32_ref_osc {
 246	struct clk_hw hw;
 247	void __iomem *ctrl_reg;
 248	const u32 *parent_map;
 249	struct pic32_clk_common *core;
 250};
 251
 252#define clkhw_to_refosc(_hw)	container_of(_hw, struct pic32_ref_osc, hw)
 253
 254static int roclk_is_enabled(struct clk_hw *hw)
 255{
 256	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 257
 258	return readl(refo->ctrl_reg) & REFO_ON;
 259}
 260
 261static int roclk_enable(struct clk_hw *hw)
 262{
 263	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 264
 265	writel(REFO_ON | REFO_OE, PIC32_SET(refo->ctrl_reg));
 266	return 0;
 267}
 268
 269static void roclk_disable(struct clk_hw *hw)
 270{
 271	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 272
 273	writel(REFO_ON | REFO_OE, PIC32_CLR(refo->ctrl_reg));
 274}
 275
 276static void roclk_init(struct clk_hw *hw)
 277{
 278	/* initialize clock in disabled state */
 279	roclk_disable(hw);
 
 
 280}
 281
 282static u8 roclk_get_parent(struct clk_hw *hw)
 283{
 284	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 285	u32 v, i;
 286
 287	v = (readl(refo->ctrl_reg) >> REFO_SEL_SHIFT) & REFO_SEL_MASK;
 288
 289	if (!refo->parent_map)
 290		return v;
 291
 292	for (i = 0; i < clk_hw_get_num_parents(hw); i++)
 293		if (refo->parent_map[i] == v)
 294			return i;
 295
 296	return -EINVAL;
 297}
 298
 299static unsigned long roclk_calc_rate(unsigned long parent_rate,
 300				     u32 rodiv, u32 rotrim)
 301{
 302	u64 rate64;
 303
 304	/* fout = fin / [2 * {div + (trim / 512)}]
 305	 *	= fin * 512 / [1024 * div + 2 * trim]
 306	 *	= fin * 256 / (512 * div + trim)
 307	 *	= (fin << 8) / ((div << 9) + trim)
 308	 */
 309	if (rotrim) {
 310		rodiv = (rodiv << 9) + rotrim;
 311		rate64 = parent_rate;
 312		rate64 <<= 8;
 313		do_div(rate64, rodiv);
 314	} else if (rodiv) {
 315		rate64 = parent_rate / (rodiv << 1);
 316	} else {
 317		rate64 = parent_rate;
 318	}
 319	return rate64;
 320}
 321
 322static void roclk_calc_div_trim(unsigned long rate,
 323				unsigned long parent_rate,
 324				u32 *rodiv_p, u32 *rotrim_p)
 325{
 326	u32 div, rotrim, rodiv;
 327	u64 frac;
 328
 329	/* Find integer approximation of floating-point arithmetic.
 330	 *      fout = fin / [2 * {rodiv + (rotrim / 512)}] ... (1)
 331	 * i.e. fout = fin / 2 * DIV
 332	 *      whereas DIV = rodiv + (rotrim / 512)
 333	 *
 334	 * Since kernel does not perform floating-point arithmatic so
 335	 * (rotrim/512) will be zero. And DIV & rodiv will result same.
 336	 *
 337	 * ie. fout = (fin * 256) / [(512 * rodiv) + rotrim]  ... from (1)
 338	 * ie. rotrim = ((fin * 256) / fout) - (512 * DIV)
 339	 */
 340	if (parent_rate <= rate) {
 341		div = 0;
 342		frac = 0;
 343		rodiv = 0;
 344		rotrim = 0;
 345	} else {
 346		div = parent_rate / (rate << 1);
 347		frac = parent_rate;
 348		frac <<= 8;
 349		do_div(frac, rate);
 350		frac -= (u64)(div << 9);
 351
 352		rodiv = (div > REFO_DIV_MASK) ? REFO_DIV_MASK : div;
 353		rotrim = (frac >= REFO_TRIM_MAX) ? REFO_TRIM_MAX : frac;
 354	}
 355
 356	if (rodiv_p)
 357		*rodiv_p = rodiv;
 358
 359	if (rotrim_p)
 360		*rotrim_p = rotrim;
 361}
 362
 363static unsigned long roclk_recalc_rate(struct clk_hw *hw,
 364				       unsigned long parent_rate)
 365{
 366	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 367	u32 v, rodiv, rotrim;
 368
 369	/* get rodiv */
 370	v = readl(refo->ctrl_reg);
 371	rodiv = (v >> REFO_DIV_SHIFT) & REFO_DIV_MASK;
 372
 373	/* get trim */
 374	v = readl(refo->ctrl_reg + REFO_TRIM_REG);
 375	rotrim = (v >> REFO_TRIM_SHIFT) & REFO_TRIM_MASK;
 376
 377	return roclk_calc_rate(parent_rate, rodiv, rotrim);
 378}
 379
 380static long roclk_round_rate(struct clk_hw *hw, unsigned long rate,
 381			     unsigned long *parent_rate)
 382{
 383	u32 rotrim, rodiv;
 384
 385	/* calculate dividers for new rate */
 386	roclk_calc_div_trim(rate, *parent_rate, &rodiv, &rotrim);
 387
 388	/* caclulate new rate (rounding) based on new rodiv & rotrim */
 389	return roclk_calc_rate(*parent_rate, rodiv, rotrim);
 390}
 391
 392static int roclk_determine_rate(struct clk_hw *hw,
 393				struct clk_rate_request *req)
 394{
 395	struct clk_hw *parent_clk, *best_parent_clk = NULL;
 396	unsigned int i, delta, best_delta = -1;
 397	unsigned long parent_rate, best_parent_rate = 0;
 398	unsigned long best = 0, nearest_rate;
 399
 400	/* find a parent which can generate nearest clkrate >= rate */
 401	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
 402		/* get parent */
 403		parent_clk = clk_hw_get_parent_by_index(hw, i);
 404		if (!parent_clk)
 405			continue;
 406
 407		/* skip if parent runs slower than target rate */
 408		parent_rate = clk_hw_get_rate(parent_clk);
 409		if (req->rate > parent_rate)
 410			continue;
 411
 412		nearest_rate = roclk_round_rate(hw, req->rate, &parent_rate);
 413		delta = abs(nearest_rate - req->rate);
 414		if ((nearest_rate >= req->rate) && (delta < best_delta)) {
 415			best_parent_clk = parent_clk;
 416			best_parent_rate = parent_rate;
 417			best = nearest_rate;
 418			best_delta = delta;
 419
 420			if (delta == 0)
 421				break;
 422		}
 423	}
 424
 425	/* if no match found, retain old rate */
 426	if (!best_parent_clk) {
 427		pr_err("%s:%s, no parent found for rate %lu.\n",
 428		       __func__, clk_hw_get_name(hw), req->rate);
 429		return clk_hw_get_rate(hw);
 430	}
 431
 432	pr_debug("%s,rate %lu, best_parent(%s, %lu), best %lu, delta %d\n",
 433		 clk_hw_get_name(hw), req->rate,
 434		 clk_hw_get_name(best_parent_clk), best_parent_rate,
 435		 best, best_delta);
 436
 437	if (req->best_parent_rate)
 438		req->best_parent_rate = best_parent_rate;
 439
 440	if (req->best_parent_hw)
 441		req->best_parent_hw = best_parent_clk;
 442
 443	return best;
 444}
 445
 446static int roclk_set_parent(struct clk_hw *hw, u8 index)
 447{
 448	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 449	unsigned long flags;
 450	u32 v;
 451	int err;
 452
 453	if (refo->parent_map)
 454		index = refo->parent_map[index];
 455
 456	/* wait until ACTIVE bit is zero or timeout */
 457	err = readl_poll_timeout(refo->ctrl_reg, v, !(v & REFO_ACTIVE),
 458				 1, LOCK_TIMEOUT_US);
 459	if (err) {
 460		pr_err("%s: poll failed, clk active\n", clk_hw_get_name(hw));
 461		return err;
 462	}
 463
 464	spin_lock_irqsave(&refo->core->reg_lock, flags);
 465
 466	pic32_syskey_unlock();
 467
 468	/* calculate & apply new */
 469	v = readl(refo->ctrl_reg);
 470	v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
 471	v |= index << REFO_SEL_SHIFT;
 472
 473	writel(v, refo->ctrl_reg);
 474
 475	spin_unlock_irqrestore(&refo->core->reg_lock, flags);
 476
 477	return 0;
 478}
 479
 480static int roclk_set_rate_and_parent(struct clk_hw *hw,
 481				     unsigned long rate,
 482				     unsigned long parent_rate,
 483				     u8 index)
 484{
 485	struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
 486	unsigned long flags;
 487	u32 trim, rodiv, v;
 488	int err;
 489
 490	/* calculate new rodiv & rotrim for new rate */
 491	roclk_calc_div_trim(rate, parent_rate, &rodiv, &trim);
 492
 493	pr_debug("parent_rate = %lu, rate = %lu, div = %d, trim = %d\n",
 494		 parent_rate, rate, rodiv, trim);
 495
 496	/* wait till source change is active */
 497	err = readl_poll_timeout(refo->ctrl_reg, v,
 498				 !(v & (REFO_ACTIVE | REFO_DIVSW_EN)),
 499				 1, LOCK_TIMEOUT_US);
 500	if (err) {
 501		pr_err("%s: poll timedout, clock is still active\n", __func__);
 502		return err;
 503	}
 504
 505	spin_lock_irqsave(&refo->core->reg_lock, flags);
 506	v = readl(refo->ctrl_reg);
 507
 508	pic32_syskey_unlock();
 509
 510	/* apply parent, if required */
 511	if (refo->parent_map)
 512		index = refo->parent_map[index];
 513
 514	v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
 515	v |= index << REFO_SEL_SHIFT;
 516
 517	/* apply RODIV */
 518	v &= ~(REFO_DIV_MASK << REFO_DIV_SHIFT);
 519	v |= rodiv << REFO_DIV_SHIFT;
 520	writel(v, refo->ctrl_reg);
 521
 522	/* apply ROTRIM */
 523	v = readl(refo->ctrl_reg + REFO_TRIM_REG);
 524	v &= ~(REFO_TRIM_MASK << REFO_TRIM_SHIFT);
 525	v |= trim << REFO_TRIM_SHIFT;
 526	writel(v, refo->ctrl_reg + REFO_TRIM_REG);
 527
 528	/* enable & activate divider switching */
 529	writel(REFO_ON | REFO_DIVSW_EN, PIC32_SET(refo->ctrl_reg));
 530
 531	/* wait till divswen is in-progress */
 532	err = readl_poll_timeout_atomic(refo->ctrl_reg, v, !(v & REFO_DIVSW_EN),
 533					1, LOCK_TIMEOUT_US);
 534	/* leave the clk gated as it was */
 535	writel(REFO_ON, PIC32_CLR(refo->ctrl_reg));
 536
 537	spin_unlock_irqrestore(&refo->core->reg_lock, flags);
 538
 539	return err;
 540}
 541
 542static int roclk_set_rate(struct clk_hw *hw, unsigned long rate,
 543			  unsigned long parent_rate)
 544{
 545	u8 index = roclk_get_parent(hw);
 546
 547	return roclk_set_rate_and_parent(hw, rate, parent_rate, index);
 548}
 549
 550const struct clk_ops pic32_roclk_ops = {
 551	.enable			= roclk_enable,
 552	.disable		= roclk_disable,
 553	.is_enabled		= roclk_is_enabled,
 554	.get_parent		= roclk_get_parent,
 555	.set_parent		= roclk_set_parent,
 556	.determine_rate		= roclk_determine_rate,
 557	.recalc_rate		= roclk_recalc_rate,
 558	.set_rate_and_parent	= roclk_set_rate_and_parent,
 559	.set_rate		= roclk_set_rate,
 560	.init			= roclk_init,
 561};
 562
 563struct clk *pic32_refo_clk_register(const struct pic32_ref_osc_data *data,
 564				    struct pic32_clk_common *core)
 565{
 566	struct pic32_ref_osc *refo;
 567	struct clk *clk;
 568
 569	refo = devm_kzalloc(core->dev, sizeof(*refo), GFP_KERNEL);
 570	if (!refo)
 571		return ERR_PTR(-ENOMEM);
 572
 573	refo->core = core;
 574	refo->hw.init = &data->init_data;
 575	refo->ctrl_reg = data->ctrl_reg + core->iobase;
 576	refo->parent_map = data->parent_map;
 577
 578	clk = devm_clk_register(core->dev, &refo->hw);
 579	if (IS_ERR(clk))
 580		dev_err(core->dev, "%s: clk_register() failed\n", __func__);
 581
 582	return clk;
 583}
 584
 585struct pic32_sys_pll {
 586	struct clk_hw hw;
 587	void __iomem *ctrl_reg;
 588	void __iomem *status_reg;
 589	u32 lock_mask;
 590	u32 idiv; /* PLL iclk divider, treated fixed */
 591	struct pic32_clk_common *core;
 592};
 593
 594#define clkhw_to_spll(_hw)	container_of(_hw, struct pic32_sys_pll, hw)
 595
 596static inline u32 spll_odiv_to_divider(u32 odiv)
 597{
 598	odiv = clamp_val(odiv, PLL_ODIV_MIN, PLL_ODIV_MAX);
 599
 600	return 1 << odiv;
 601}
 602
 603static unsigned long spll_calc_mult_div(struct pic32_sys_pll *pll,
 604					unsigned long rate,
 605					unsigned long parent_rate,
 606					u32 *mult_p, u32 *odiv_p)
 607{
 608	u32 mul, div, best_mul = 1, best_div = 1;
 609	unsigned long new_rate, best_rate = rate;
 610	unsigned int best_delta = -1, delta, match_found = 0;
 611	u64 rate64;
 612
 613	parent_rate /= pll->idiv;
 614
 615	for (mul = 1; mul <= PLL_MULT_MAX; mul++) {
 616		for (div = PLL_ODIV_MIN; div <= PLL_ODIV_MAX; div++) {
 617			rate64 = parent_rate;
 618			rate64 *= mul;
 619			do_div(rate64, 1 << div);
 620			new_rate = rate64;
 621			delta = abs(rate - new_rate);
 622			if ((new_rate >= rate) && (delta < best_delta)) {
 623				best_delta = delta;
 624				best_rate = new_rate;
 625				best_mul = mul;
 626				best_div = div;
 627				match_found = 1;
 628			}
 629		}
 630	}
 631
 632	if (!match_found) {
 633		pr_warn("spll: no match found\n");
 634		return 0;
 635	}
 636
 637	pr_debug("rate %lu, par_rate %lu/mult %u, div %u, best_rate %lu\n",
 638		 rate, parent_rate, best_mul, best_div, best_rate);
 639
 640	if (mult_p)
 641		*mult_p = best_mul - 1;
 642
 643	if (odiv_p)
 644		*odiv_p = best_div;
 645
 646	return best_rate;
 647}
 648
 649static unsigned long spll_clk_recalc_rate(struct clk_hw *hw,
 650					  unsigned long parent_rate)
 651{
 652	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 653	unsigned long pll_in_rate;
 654	u32 mult, odiv, div, v;
 655	u64 rate64;
 656
 657	v = readl(pll->ctrl_reg);
 658	odiv = ((v >> PLL_ODIV_SHIFT) & PLL_ODIV_MASK);
 659	mult = ((v >> PLL_MULT_SHIFT) & PLL_MULT_MASK) + 1;
 660	div = spll_odiv_to_divider(odiv);
 661
 662	/* pll_in_rate = parent_rate / idiv
 663	 * pll_out_rate = pll_in_rate * mult / div;
 664	 */
 665	pll_in_rate = parent_rate / pll->idiv;
 666	rate64 = pll_in_rate;
 667	rate64 *= mult;
 668	do_div(rate64, div);
 669
 670	return rate64;
 671}
 672
 673static long spll_clk_round_rate(struct clk_hw *hw, unsigned long rate,
 674				unsigned long *parent_rate)
 675{
 676	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 677
 678	return spll_calc_mult_div(pll, rate, *parent_rate, NULL, NULL);
 679}
 680
 681static int spll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 682			     unsigned long parent_rate)
 683{
 684	struct pic32_sys_pll *pll = clkhw_to_spll(hw);
 685	unsigned long ret, flags;
 686	u32 mult, odiv, v;
 687	int err;
 688
 689	ret = spll_calc_mult_div(pll, rate, parent_rate, &mult, &odiv);
 690	if (!ret)
 691		return -EINVAL;
 692
 693	/*
 694	 * We can't change SPLL counters when it is in-active use
 695	 * by SYSCLK. So check before applying new counters/rate.
 696	 */
 697
 698	/* Is spll_clk active parent of sys_clk ? */
 699	if (unlikely(clk_hw_get_parent(pic32_sclk_hw) == hw)) {
 700		pr_err("%s: failed, clk in-use\n", __func__);
 701		return -EBUSY;
 702	}
 703
 704	spin_lock_irqsave(&pll->core->reg_lock, flags);
 705
 706	/* apply new multiplier & divisor */
 707	v = readl(pll->ctrl_reg);
 708	v &= ~(PLL_MULT_MASK << PLL_MULT_SHIFT);
 709	v &= ~(PLL_ODIV_MASK << PLL_ODIV_SHIFT);
 710	v |= (mult << PLL_MULT_SHIFT) | (odiv << PLL_ODIV_SHIFT);
 711
 712	/* sys unlock before write */
 713	pic32_syskey_unlock();
 714
 715	writel(v, pll->ctrl_reg);
 716	cpu_relax();
 717
 718	/* insert few nops (5-stage) to ensure CPU does not hang */
 719	cpu_nop5();
 720	cpu_nop5();
 721
 722	/* Wait until PLL is locked (maximum 100 usecs). */
 723	err = readl_poll_timeout_atomic(pll->status_reg, v,
 724					v & pll->lock_mask, 1, 100);
 725	spin_unlock_irqrestore(&pll->core->reg_lock, flags);
 726
 727	return err;
 728}
 729
 730/* SPLL clock operation */
 731const struct clk_ops pic32_spll_ops = {
 732	.recalc_rate	= spll_clk_recalc_rate,
 733	.round_rate	= spll_clk_round_rate,
 734	.set_rate	= spll_clk_set_rate,
 735};
 736
 737struct clk *pic32_spll_clk_register(const struct pic32_sys_pll_data *data,
 738				    struct pic32_clk_common *core)
 739{
 740	struct pic32_sys_pll *spll;
 741	struct clk *clk;
 742
 743	spll = devm_kzalloc(core->dev, sizeof(*spll), GFP_KERNEL);
 744	if (!spll)
 745		return ERR_PTR(-ENOMEM);
 746
 747	spll->core = core;
 748	spll->hw.init = &data->init_data;
 749	spll->ctrl_reg = data->ctrl_reg + core->iobase;
 750	spll->status_reg = data->status_reg + core->iobase;
 751	spll->lock_mask = data->lock_mask;
 752
 753	/* cache PLL idiv; PLL driver uses it as constant.*/
 754	spll->idiv = (readl(spll->ctrl_reg) >> PLL_IDIV_SHIFT) & PLL_IDIV_MASK;
 755	spll->idiv += 1;
 756
 757	clk = devm_clk_register(core->dev, &spll->hw);
 758	if (IS_ERR(clk))
 759		dev_err(core->dev, "sys_pll: clk_register() failed\n");
 760
 761	return clk;
 762}
 763
 764/* System mux clock(aka SCLK) */
 765
 766struct pic32_sys_clk {
 767	struct clk_hw hw;
 768	void __iomem *mux_reg;
 769	void __iomem *slew_reg;
 770	u32 slew_div;
 771	const u32 *parent_map;
 772	struct pic32_clk_common *core;
 773};
 774
 775#define clkhw_to_sys_clk(_hw)	container_of(_hw, struct pic32_sys_clk, hw)
 776
 777static unsigned long sclk_get_rate(struct clk_hw *hw, unsigned long parent_rate)
 778{
 779	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 780	u32 div;
 781
 782	div = (readl(sclk->slew_reg) >> SLEW_SYSDIV_SHIFT) & SLEW_SYSDIV;
 783	div += 1; /* sys-div to divider */
 784
 785	return parent_rate / div;
 786}
 787
 788static long sclk_round_rate(struct clk_hw *hw, unsigned long rate,
 789			    unsigned long *parent_rate)
 790{
 791	return calc_best_divided_rate(rate, *parent_rate, SLEW_SYSDIV, 1);
 792}
 793
 794static int sclk_set_rate(struct clk_hw *hw,
 795			 unsigned long rate, unsigned long parent_rate)
 796{
 797	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 798	unsigned long flags;
 799	u32 v, div;
 800	int err;
 801
 802	div = parent_rate / rate;
 803
 804	spin_lock_irqsave(&sclk->core->reg_lock, flags);
 805
 806	/* apply new div */
 807	v = readl(sclk->slew_reg);
 808	v &= ~(SLEW_SYSDIV << SLEW_SYSDIV_SHIFT);
 809	v |= (div - 1) << SLEW_SYSDIV_SHIFT;
 810
 811	pic32_syskey_unlock();
 812
 813	writel(v, sclk->slew_reg);
 814
 815	/* wait until BUSY is cleared */
 816	err = readl_poll_timeout_atomic(sclk->slew_reg, v,
 817					!(v & SLEW_BUSY), 1, LOCK_TIMEOUT_US);
 818
 819	spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 820
 821	return err;
 822}
 823
 824static u8 sclk_get_parent(struct clk_hw *hw)
 825{
 826	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 827	u32 i, v;
 828
 829	v = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
 830
 831	if (!sclk->parent_map)
 832		return v;
 833
 834	for (i = 0; i < clk_hw_get_num_parents(hw); i++)
 835		if (sclk->parent_map[i] == v)
 836			return i;
 837	return -EINVAL;
 838}
 839
 840static int sclk_set_parent(struct clk_hw *hw, u8 index)
 841{
 842	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 843	unsigned long flags;
 844	u32 nosc, cosc, v;
 845	int err;
 846
 847	spin_lock_irqsave(&sclk->core->reg_lock, flags);
 848
 849	/* find new_osc */
 850	nosc = sclk->parent_map ? sclk->parent_map[index] : index;
 851
 852	/* set new parent */
 853	v = readl(sclk->mux_reg);
 854	v &= ~(OSC_NEW_MASK << OSC_NEW_SHIFT);
 855	v |= nosc << OSC_NEW_SHIFT;
 856
 857	pic32_syskey_unlock();
 858
 859	writel(v, sclk->mux_reg);
 860
 861	/* initate switch */
 862	writel(OSC_SWEN, PIC32_SET(sclk->mux_reg));
 863	cpu_relax();
 864
 865	/* add nop to flush pipeline (as cpu_clk is in-flux) */
 866	cpu_nop5();
 867
 868	/* wait for SWEN bit to clear */
 869	err = readl_poll_timeout_atomic(sclk->slew_reg, v,
 870					!(v & OSC_SWEN), 1, LOCK_TIMEOUT_US);
 871
 872	spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 873
 874	/*
 875	 * SCLK clock-switching logic might reject a clock switching request
 876	 * if pre-requisites (like new clk_src not present or unstable) are
 877	 * not met.
 878	 * So confirm before claiming success.
 879	 */
 880	cosc = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
 881	if (cosc != nosc) {
 882		pr_err("%s: err, failed to set_parent() to %d, current %d\n",
 883		       clk_hw_get_name(hw), nosc, cosc);
 884		err = -EBUSY;
 885	}
 886
 887	return err;
 888}
 889
 890static void sclk_init(struct clk_hw *hw)
 891{
 892	struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
 893	unsigned long flags;
 894	u32 v;
 895
 896	/* Maintain reference to this clk, required in spll_clk_set_rate() */
 897	pic32_sclk_hw = hw;
 898
 899	/* apply slew divider on both up and down scaling */
 900	if (sclk->slew_div) {
 901		spin_lock_irqsave(&sclk->core->reg_lock, flags);
 902		v = readl(sclk->slew_reg);
 903		v &= ~(SLEW_DIV << SLEW_DIV_SHIFT);
 904		v |= sclk->slew_div << SLEW_DIV_SHIFT;
 905		v |= SLEW_DOWNEN | SLEW_UPEN;
 906		writel(v, sclk->slew_reg);
 907		spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
 908	}
 
 
 909}
 910
 911/* sclk with post-divider */
 912const struct clk_ops pic32_sclk_ops = {
 913	.get_parent	= sclk_get_parent,
 914	.set_parent	= sclk_set_parent,
 915	.round_rate	= sclk_round_rate,
 916	.set_rate	= sclk_set_rate,
 917	.recalc_rate	= sclk_get_rate,
 918	.init		= sclk_init,
 919	.determine_rate = __clk_mux_determine_rate,
 920};
 921
 922/* sclk with no slew and no post-divider */
 923const struct clk_ops pic32_sclk_no_div_ops = {
 924	.get_parent	= sclk_get_parent,
 925	.set_parent	= sclk_set_parent,
 926	.init		= sclk_init,
 927	.determine_rate = __clk_mux_determine_rate,
 928};
 929
 930struct clk *pic32_sys_clk_register(const struct pic32_sys_clk_data *data,
 931				   struct pic32_clk_common *core)
 932{
 933	struct pic32_sys_clk *sclk;
 934	struct clk *clk;
 935
 936	sclk = devm_kzalloc(core->dev, sizeof(*sclk), GFP_KERNEL);
 937	if (!sclk)
 938		return ERR_PTR(-ENOMEM);
 939
 940	sclk->core = core;
 941	sclk->hw.init = &data->init_data;
 942	sclk->mux_reg = data->mux_reg + core->iobase;
 943	sclk->slew_reg = data->slew_reg + core->iobase;
 944	sclk->slew_div = data->slew_div;
 945	sclk->parent_map = data->parent_map;
 946
 947	clk = devm_clk_register(core->dev, &sclk->hw);
 948	if (IS_ERR(clk))
 949		dev_err(core->dev, "%s: clk register failed\n", __func__);
 950
 951	return clk;
 952}
 953
 954/* secondary oscillator */
 955struct pic32_sec_osc {
 956	struct clk_hw hw;
 957	void __iomem *enable_reg;
 958	void __iomem *status_reg;
 959	u32 enable_mask;
 960	u32 status_mask;
 961	unsigned long fixed_rate;
 962	struct pic32_clk_common *core;
 963};
 964
 965#define clkhw_to_sosc(_hw)	container_of(_hw, struct pic32_sec_osc, hw)
 966static int sosc_clk_enable(struct clk_hw *hw)
 967{
 968	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 969	u32 v;
 970
 971	/* enable SOSC */
 972	pic32_syskey_unlock();
 973	writel(sosc->enable_mask, PIC32_SET(sosc->enable_reg));
 974
 975	/* wait till warm-up period expires or ready-status is updated */
 976	return readl_poll_timeout_atomic(sosc->status_reg, v,
 977					 v & sosc->status_mask, 1, 100);
 978}
 979
 980static void sosc_clk_disable(struct clk_hw *hw)
 981{
 982	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 983
 984	pic32_syskey_unlock();
 985	writel(sosc->enable_mask, PIC32_CLR(sosc->enable_reg));
 986}
 987
 988static int sosc_clk_is_enabled(struct clk_hw *hw)
 989{
 990	struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
 991	u32 enabled, ready;
 992
 993	/* check enabled and ready status */
 994	enabled = readl(sosc->enable_reg) & sosc->enable_mask;
 995	ready = readl(sosc->status_reg) & sosc->status_mask;
 996
 997	return enabled && ready;
 998}
 999
1000static unsigned long sosc_clk_calc_rate(struct clk_hw *hw,
1001					unsigned long parent_rate)
1002{
1003	return clkhw_to_sosc(hw)->fixed_rate;
1004}
1005
1006const struct clk_ops pic32_sosc_ops = {
1007	.enable = sosc_clk_enable,
1008	.disable = sosc_clk_disable,
1009	.is_enabled = sosc_clk_is_enabled,
1010	.recalc_rate = sosc_clk_calc_rate,
1011};
1012
1013struct clk *pic32_sosc_clk_register(const struct pic32_sec_osc_data *data,
1014				    struct pic32_clk_common *core)
1015{
1016	struct pic32_sec_osc *sosc;
1017
1018	sosc = devm_kzalloc(core->dev, sizeof(*sosc), GFP_KERNEL);
1019	if (!sosc)
1020		return ERR_PTR(-ENOMEM);
1021
1022	sosc->core = core;
1023	sosc->hw.init = &data->init_data;
1024	sosc->fixed_rate = data->fixed_rate;
1025	sosc->enable_mask = data->enable_mask;
1026	sosc->status_mask = data->status_mask;
1027	sosc->enable_reg = data->enable_reg + core->iobase;
1028	sosc->status_reg = data->status_reg + core->iobase;
1029
1030	return devm_clk_register(core->dev, &sosc->hw);
1031}