1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2014 Texas Instruments Incorporated
4 */
5
6#define DSS_SUBSYS_NAME "PLL"
7
8#include <linux/clk.h>
9#include <linux/io.h>
10#include <linux/kernel.h>
11#include <linux/regulator/consumer.h>
12#include <linux/sched.h>
13
14#include <video/omapfb_dss.h>
15
16#include "dss.h"
17
18#define PLL_CONTROL			0x0000
19#define PLL_STATUS			0x0004
20#define PLL_GO				0x0008
21#define PLL_CONFIGURATION1		0x000C
22#define PLL_CONFIGURATION2		0x0010
23#define PLL_CONFIGURATION3		0x0014
24#define PLL_SSC_CONFIGURATION1		0x0018
25#define PLL_SSC_CONFIGURATION2		0x001C
26#define PLL_CONFIGURATION4		0x0020
27
28static struct dss_pll *dss_plls[4];
29
30int dss_pll_register(struct dss_pll *pll)
31{
32	int i;
33
34	for (i = 0; i < ARRAY_SIZE(dss_plls); ++i) {
35		if (!dss_plls[i]) {
36			dss_plls[i] = pll;
37			return 0;
38		}
39	}
40
41	return -EBUSY;
42}
43
44void dss_pll_unregister(struct dss_pll *pll)
45{
46	int i;
47
48	for (i = 0; i < ARRAY_SIZE(dss_plls); ++i) {
49		if (dss_plls[i] == pll) {
50			dss_plls[i] = NULL;
51			return;
52		}
53	}
54}
55
56struct dss_pll *dss_pll_find(const char *name)
57{
58	int i;
59
60	for (i = 0; i < ARRAY_SIZE(dss_plls); ++i) {
61		if (dss_plls[i] && strcmp(dss_plls[i]->name, name) == 0)
62			return dss_plls[i];
63	}
64
65	return NULL;
66}
67
68int dss_pll_enable(struct dss_pll *pll)
69{
70	int r;
71
72	r = clk_prepare_enable(pll->clkin);
73	if (r)
74		return r;
75
76	if (pll->regulator) {
77		r = regulator_enable(pll->regulator);
78		if (r)
79			goto err_reg;
80	}
81
82	r = pll->ops->enable(pll);
83	if (r)
84		goto err_enable;
85
86	return 0;
87
88err_enable:
89	if (pll->regulator)
90		regulator_disable(pll->regulator);
91err_reg:
92	clk_disable_unprepare(pll->clkin);
93	return r;
94}
95
96void dss_pll_disable(struct dss_pll *pll)
97{
98	pll->ops->disable(pll);
99
100	if (pll->regulator)
101		regulator_disable(pll->regulator);
102
103	clk_disable_unprepare(pll->clkin);
104
105	memset(&pll->cinfo, 0, sizeof(pll->cinfo));
106}
107
108int dss_pll_set_config(struct dss_pll *pll, const struct dss_pll_clock_info *cinfo)
109{
110	int r;
111
112	r = pll->ops->set_config(pll, cinfo);
113	if (r)
114		return r;
115
116	pll->cinfo = *cinfo;
117
118	return 0;
119}
120
121bool dss_pll_hsdiv_calc(const struct dss_pll *pll, unsigned long clkdco,
122		unsigned long out_min, unsigned long out_max,
123		dss_hsdiv_calc_func func, void *data)
124{
125	const struct dss_pll_hw *hw = pll->hw;
126	int m, m_start, m_stop;
127	unsigned long out;
128
129	out_min = out_min ? out_min : 1;
130	out_max = out_max ? out_max : ULONG_MAX;
131
132	m_start = max(DIV_ROUND_UP(clkdco, out_max), 1ul);
133
134	m_stop = min((unsigned)(clkdco / out_min), hw->mX_max);
135
136	for (m = m_start; m <= m_stop; ++m) {
137		out = clkdco / m;
138
139		if (func(m, out, data))
140			return true;
141	}
142
143	return false;
144}
145
146bool dss_pll_calc(const struct dss_pll *pll, unsigned long clkin,
147		unsigned long pll_min, unsigned long pll_max,
148		dss_pll_calc_func func, void *data)
149{
150	const struct dss_pll_hw *hw = pll->hw;
151	int n, n_start, n_stop;
152	int m, m_start, m_stop;
153	unsigned long fint, clkdco;
154	unsigned long pll_hw_max;
155	unsigned long fint_hw_min, fint_hw_max;
156
157	pll_hw_max = hw->clkdco_max;
158
159	fint_hw_min = hw->fint_min;
160	fint_hw_max = hw->fint_max;
161
162	n_start = max(DIV_ROUND_UP(clkin, fint_hw_max), 1ul);
163	n_stop = min((unsigned)(clkin / fint_hw_min), hw->n_max);
164
165	pll_max = pll_max ? pll_max : ULONG_MAX;
166
167	for (n = n_start; n <= n_stop; ++n) {
168		fint = clkin / n;
169
170		m_start = max(DIV_ROUND_UP(DIV_ROUND_UP(pll_min, fint), 2),
171				1ul);
172		m_stop = min3((unsigned)(pll_max / fint / 2),
173				(unsigned)(pll_hw_max / fint / 2),
174				hw->m_max);
175
176		for (m = m_start; m <= m_stop; ++m) {
177			clkdco = 2 * m * fint;
178
179			if (func(n, m, fint, clkdco, data))
180				return true;
181		}
182	}
183
184	return false;
185}
186
187static int wait_for_bit_change(void __iomem *reg, int bitnum, int value)
188{
189	unsigned long timeout;
190	ktime_t wait;
191	int t;
192
193	/* first busyloop to see if the bit changes right away */
194	t = 100;
195	while (t-- > 0) {
196		if (FLD_GET(readl_relaxed(reg), bitnum, bitnum) == value)
197			return value;
198	}
199
200	/* then loop for 500ms, sleeping for 1ms in between */
201	timeout = jiffies + msecs_to_jiffies(500);
202	while (time_before(jiffies, timeout)) {
203		if (FLD_GET(readl_relaxed(reg), bitnum, bitnum) == value)
204			return value;
205
206		wait = ns_to_ktime(1000 * 1000);
207		set_current_state(TASK_UNINTERRUPTIBLE);
208		schedule_hrtimeout(&wait, HRTIMER_MODE_REL);
209	}
210
211	return !value;
212}
213
214int dss_pll_wait_reset_done(struct dss_pll *pll)
215{
216	void __iomem *base = pll->base;
217
218	if (wait_for_bit_change(base + PLL_STATUS, 0, 1) != 1)
219		return -ETIMEDOUT;
220	else
221		return 0;
222}
223
224static int dss_wait_hsdiv_ack(struct dss_pll *pll, u32 hsdiv_ack_mask)
225{
226	int t = 100;
227
228	while (t-- > 0) {
229		u32 v = readl_relaxed(pll->base + PLL_STATUS);
230		v &= hsdiv_ack_mask;
231		if (v == hsdiv_ack_mask)
232			return 0;
233	}
234
235	return -ETIMEDOUT;
236}
237
238int dss_pll_write_config_type_a(struct dss_pll *pll,
239		const struct dss_pll_clock_info *cinfo)
240{
241	const struct dss_pll_hw *hw = pll->hw;
242	void __iomem *base = pll->base;
243	int r = 0;
244	u32 l;
245
246	l = 0;
247	if (hw->has_stopmode)
248		l = FLD_MOD(l, 1, 0, 0);		/* PLL_STOPMODE */
249	l = FLD_MOD(l, cinfo->n - 1, hw->n_msb, hw->n_lsb);	/* PLL_REGN */
250	l = FLD_MOD(l, cinfo->m, hw->m_msb, hw->m_lsb);		/* PLL_REGM */
251	/* M4 */
252	l = FLD_MOD(l, cinfo->mX[0] ? cinfo->mX[0] - 1 : 0,
253			hw->mX_msb[0], hw->mX_lsb[0]);
254	/* M5 */
255	l = FLD_MOD(l, cinfo->mX[1] ? cinfo->mX[1] - 1 : 0,
256			hw->mX_msb[1], hw->mX_lsb[1]);
257	writel_relaxed(l, base + PLL_CONFIGURATION1);
258
259	l = 0;
260	/* M6 */
261	l = FLD_MOD(l, cinfo->mX[2] ? cinfo->mX[2] - 1 : 0,
262			hw->mX_msb[2], hw->mX_lsb[2]);
263	/* M7 */
264	l = FLD_MOD(l, cinfo->mX[3] ? cinfo->mX[3] - 1 : 0,
265			hw->mX_msb[3], hw->mX_lsb[3]);
266	writel_relaxed(l, base + PLL_CONFIGURATION3);
267
268	l = readl_relaxed(base + PLL_CONFIGURATION2);
269	if (hw->has_freqsel) {
270		u32 f = cinfo->fint < 1000000 ? 0x3 :
271			cinfo->fint < 1250000 ? 0x4 :
272			cinfo->fint < 1500000 ? 0x5 :
273			cinfo->fint < 1750000 ? 0x6 :
274			0x7;
275
276		l = FLD_MOD(l, f, 4, 1);	/* PLL_FREQSEL */
277	} else if (hw->has_selfreqdco) {
278		u32 f = cinfo->clkdco < hw->clkdco_low ? 0x2 : 0x4;
279
280		l = FLD_MOD(l, f, 3, 1);	/* PLL_SELFREQDCO */
281	}
282	l = FLD_MOD(l, 1, 13, 13);		/* PLL_REFEN */
283	l = FLD_MOD(l, 0, 14, 14);		/* PHY_CLKINEN */
284	l = FLD_MOD(l, 0, 16, 16);		/* M4_CLOCK_EN */
285	l = FLD_MOD(l, 0, 18, 18);		/* M5_CLOCK_EN */
286	l = FLD_MOD(l, 1, 20, 20);		/* HSDIVBYPASS */
287	if (hw->has_refsel)
288		l = FLD_MOD(l, 3, 22, 21);	/* REFSEL = sysclk */
289	l = FLD_MOD(l, 0, 23, 23);		/* M6_CLOCK_EN */
290	l = FLD_MOD(l, 0, 25, 25);		/* M7_CLOCK_EN */
291	writel_relaxed(l, base + PLL_CONFIGURATION2);
292
293	writel_relaxed(1, base + PLL_GO);	/* PLL_GO */
294
295	if (wait_for_bit_change(base + PLL_GO, 0, 0) != 0) {
296		DSSERR("DSS DPLL GO bit not going down.\n");
297		r = -EIO;
298		goto err;
299	}
300
301	if (wait_for_bit_change(base + PLL_STATUS, 1, 1) != 1) {
302		DSSERR("cannot lock DSS DPLL\n");
303		r = -EIO;
304		goto err;
305	}
306
307	l = readl_relaxed(base + PLL_CONFIGURATION2);
308	l = FLD_MOD(l, 1, 14, 14);			/* PHY_CLKINEN */
309	l = FLD_MOD(l, cinfo->mX[0] ? 1 : 0, 16, 16);	/* M4_CLOCK_EN */
310	l = FLD_MOD(l, cinfo->mX[1] ? 1 : 0, 18, 18);	/* M5_CLOCK_EN */
311	l = FLD_MOD(l, 0, 20, 20);			/* HSDIVBYPASS */
312	l = FLD_MOD(l, cinfo->mX[2] ? 1 : 0, 23, 23);	/* M6_CLOCK_EN */
313	l = FLD_MOD(l, cinfo->mX[3] ? 1 : 0, 25, 25);	/* M7_CLOCK_EN */
314	writel_relaxed(l, base + PLL_CONFIGURATION2);
315
316	r = dss_wait_hsdiv_ack(pll,
317		(cinfo->mX[0] ? BIT(7) : 0) |
318		(cinfo->mX[1] ? BIT(8) : 0) |
319		(cinfo->mX[2] ? BIT(10) : 0) |
320		(cinfo->mX[3] ? BIT(11) : 0));
321	if (r) {
322		DSSERR("failed to enable HSDIV clocks\n");
323		goto err;
324	}
325
326err:
327	return r;
328}
329
330int dss_pll_write_config_type_b(struct dss_pll *pll,
331		const struct dss_pll_clock_info *cinfo)
332{
333	const struct dss_pll_hw *hw = pll->hw;
334	void __iomem *base = pll->base;
335	u32 l;
336
337	l = 0;
338	l = FLD_MOD(l, cinfo->m, 20, 9);	/* PLL_REGM */
339	l = FLD_MOD(l, cinfo->n - 1, 8, 1);	/* PLL_REGN */
340	writel_relaxed(l, base + PLL_CONFIGURATION1);
341
342	l = readl_relaxed(base + PLL_CONFIGURATION2);
343	l = FLD_MOD(l, 0x0, 12, 12);	/* PLL_HIGHFREQ divide by 2 */
344	l = FLD_MOD(l, 0x1, 13, 13);	/* PLL_REFEN */
345	l = FLD_MOD(l, 0x0, 14, 14);	/* PHY_CLKINEN */
346	if (hw->has_refsel)
347		l = FLD_MOD(l, 0x3, 22, 21);	/* REFSEL = SYSCLK */
348
349	/* PLL_SELFREQDCO */
350	if (cinfo->clkdco > hw->clkdco_low)
351		l = FLD_MOD(l, 0x4, 3, 1);
352	else
353		l = FLD_MOD(l, 0x2, 3, 1);
354	writel_relaxed(l, base + PLL_CONFIGURATION2);
355
356	l = readl_relaxed(base + PLL_CONFIGURATION3);
357	l = FLD_MOD(l, cinfo->sd, 17, 10);	/* PLL_REGSD */
358	writel_relaxed(l, base + PLL_CONFIGURATION3);
359
360	l = readl_relaxed(base + PLL_CONFIGURATION4);
361	l = FLD_MOD(l, cinfo->mX[0], 24, 18);	/* PLL_REGM2 */
362	l = FLD_MOD(l, cinfo->mf, 17, 0);	/* PLL_REGM_F */
363	writel_relaxed(l, base + PLL_CONFIGURATION4);
364
365	writel_relaxed(1, base + PLL_GO);	/* PLL_GO */
366
367	if (wait_for_bit_change(base + PLL_GO, 0, 0) != 0) {
368		DSSERR("DSS DPLL GO bit not going down.\n");
369		return -EIO;
370	}
371
372	if (wait_for_bit_change(base + PLL_STATUS, 1, 1) != 1) {
373		DSSERR("cannot lock DSS DPLL\n");
374		return -ETIMEDOUT;
375	}
376
377	return 0;
378}
379