1 /*
2  * Copyright (c) 2014 Marvell Technology Group Ltd.
3  *
4  * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
5  * Alexandre Belloni <alexandre.belloni@free-electrons.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 #include <linux/clk-provider.h>
20 #include <linux/io.h>
21 #include <linux/kernel.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/slab.h>
25 
26 #include "berlin2-avpll.h"
27 
28 /*
29  * Berlin2 SoCs comprise up to two PLLs called AVPLL built upon a
30  * VCO with 8 channels each, channel 8 is the odd-one-out and does
31  * not provide mul/div.
32  *
33  * Unfortunately, its registers are not named but just numbered. To
34  * get in at least some kind of structure, we split each AVPLL into
35  * the VCOs and each channel into separate clock drivers.
36  *
37  * Also, here and there the VCO registers are a bit different with
38  * respect to bit shifts. Make sure to add a comment for those.
39  */
40 #define NUM_CHANNELS	8
41 
42 #define AVPLL_CTRL(x)		((x) * 0x4)
43 
44 #define VCO_CTRL0		AVPLL_CTRL(0)
45 /* BG2/BG2CDs VCO_B has an additional shift of 4 for its VCO_CTRL0 reg */
46 #define  VCO_RESET		BIT(0)
47 #define  VCO_POWERUP		BIT(1)
48 #define  VCO_INTERPOL_SHIFT	2
49 #define  VCO_INTERPOL_MASK	(0xf << VCO_INTERPOL_SHIFT)
50 #define  VCO_REG1V45_SEL_SHIFT	6
51 #define  VCO_REG1V45_SEL(x)	((x) << VCO_REG1V45_SEL_SHIFT)
52 #define  VCO_REG1V45_SEL_1V40	VCO_REG1V45_SEL(0)
53 #define  VCO_REG1V45_SEL_1V45	VCO_REG1V45_SEL(1)
54 #define  VCO_REG1V45_SEL_1V50	VCO_REG1V45_SEL(2)
55 #define  VCO_REG1V45_SEL_1V55	VCO_REG1V45_SEL(3)
56 #define  VCO_REG1V45_SEL_MASK	VCO_REG1V45_SEL(3)
57 #define  VCO_REG0V9_SEL_SHIFT	8
58 #define  VCO_REG0V9_SEL_MASK	(0xf << VCO_REG0V9_SEL_SHIFT)
59 #define  VCO_VTHCAL_SHIFT	12
60 #define  VCO_VTHCAL(x)		((x) << VCO_VTHCAL_SHIFT)
61 #define  VCO_VTHCAL_0V90	VCO_VTHCAL(0)
62 #define  VCO_VTHCAL_0V95	VCO_VTHCAL(1)
63 #define  VCO_VTHCAL_1V00	VCO_VTHCAL(2)
64 #define  VCO_VTHCAL_1V05	VCO_VTHCAL(3)
65 #define  VCO_VTHCAL_MASK	VCO_VTHCAL(3)
66 #define  VCO_KVCOEXT_SHIFT	14
67 #define  VCO_KVCOEXT_MASK	(0x3 << VCO_KVCOEXT_SHIFT)
68 #define  VCO_KVCOEXT_ENABLE	BIT(17)
69 #define  VCO_V2IEXT_SHIFT	18
70 #define  VCO_V2IEXT_MASK	(0xf << VCO_V2IEXT_SHIFT)
71 #define  VCO_V2IEXT_ENABLE	BIT(22)
72 #define  VCO_SPEED_SHIFT	23
73 #define  VCO_SPEED(x)		((x) << VCO_SPEED_SHIFT)
74 #define  VCO_SPEED_1G08_1G21	VCO_SPEED(0)
75 #define  VCO_SPEED_1G21_1G40	VCO_SPEED(1)
76 #define  VCO_SPEED_1G40_1G61	VCO_SPEED(2)
77 #define  VCO_SPEED_1G61_1G86	VCO_SPEED(3)
78 #define  VCO_SPEED_1G86_2G00	VCO_SPEED(4)
79 #define  VCO_SPEED_2G00_2G22	VCO_SPEED(5)
80 #define  VCO_SPEED_2G22		VCO_SPEED(6)
81 #define  VCO_SPEED_MASK		VCO_SPEED(0x7)
82 #define  VCO_CLKDET_ENABLE	BIT(26)
83 #define VCO_CTRL1		AVPLL_CTRL(1)
84 #define  VCO_REFDIV_SHIFT	0
85 #define  VCO_REFDIV(x)		((x) << VCO_REFDIV_SHIFT)
86 #define  VCO_REFDIV_1		VCO_REFDIV(0)
87 #define  VCO_REFDIV_2		VCO_REFDIV(1)
88 #define  VCO_REFDIV_4		VCO_REFDIV(2)
89 #define  VCO_REFDIV_3		VCO_REFDIV(3)
90 #define  VCO_REFDIV_MASK	VCO_REFDIV(0x3f)
91 #define  VCO_FBDIV_SHIFT	6
92 #define  VCO_FBDIV(x)		((x) << VCO_FBDIV_SHIFT)
93 #define  VCO_FBDIV_MASK		VCO_FBDIV(0xff)
94 #define  VCO_ICP_SHIFT		14
95 /* PLL Charge Pump Current = 10uA * (x + 1) */
96 #define  VCO_ICP(x)		((x) << VCO_ICP_SHIFT)
97 #define  VCO_ICP_MASK		VCO_ICP(0xf)
98 #define  VCO_LOAD_CAP		BIT(18)
99 #define  VCO_CALIBRATION_START	BIT(19)
100 #define VCO_FREQOFFSETn(x)	AVPLL_CTRL(3 + (x))
101 #define  VCO_FREQOFFSET_MASK	0x7ffff
102 #define VCO_CTRL10		AVPLL_CTRL(10)
103 #define  VCO_POWERUP_CH1	BIT(20)
104 #define VCO_CTRL11		AVPLL_CTRL(11)
105 #define VCO_CTRL12		AVPLL_CTRL(12)
106 #define VCO_CTRL13		AVPLL_CTRL(13)
107 #define VCO_CTRL14		AVPLL_CTRL(14)
108 #define VCO_CTRL15		AVPLL_CTRL(15)
109 #define VCO_SYNC1n(x)		AVPLL_CTRL(15 + (x))
110 #define  VCO_SYNC1_MASK		0x1ffff
111 #define VCO_SYNC2n(x)		AVPLL_CTRL(23 + (x))
112 #define  VCO_SYNC2_MASK		0x1ffff
113 #define VCO_CTRL30		AVPLL_CTRL(30)
114 #define  VCO_DPLL_CH1_ENABLE	BIT(17)
115 
116 struct berlin2_avpll_vco {
117 	struct clk_hw hw;
118 	void __iomem *base;
119 	u8 flags;
120 };
121 
122 #define to_avpll_vco(hw) container_of(hw, struct berlin2_avpll_vco, hw)
123 
124 static int berlin2_avpll_vco_is_enabled(struct clk_hw *hw)
125 {
126 	struct berlin2_avpll_vco *vco = to_avpll_vco(hw);
127 	u32 reg;
128 
129 	reg = readl_relaxed(vco->base + VCO_CTRL0);
130 	if (vco->flags & BERLIN2_AVPLL_BIT_QUIRK)
131 		reg >>= 4;
132 
133 	return !!(reg & VCO_POWERUP);
134 }
135 
136 static int berlin2_avpll_vco_enable(struct clk_hw *hw)
137 {
138 	struct berlin2_avpll_vco *vco = to_avpll_vco(hw);
139 	u32 reg;
140 
141 	reg = readl_relaxed(vco->base + VCO_CTRL0);
142 	if (vco->flags & BERLIN2_AVPLL_BIT_QUIRK)
143 		reg |= VCO_POWERUP << 4;
144 	else
145 		reg |= VCO_POWERUP;
146 	writel_relaxed(reg, vco->base + VCO_CTRL0);
147 
148 	return 0;
149 }
150 
151 static void berlin2_avpll_vco_disable(struct clk_hw *hw)
152 {
153 	struct berlin2_avpll_vco *vco = to_avpll_vco(hw);
154 	u32 reg;
155 
156 	reg = readl_relaxed(vco->base + VCO_CTRL0);
157 	if (vco->flags & BERLIN2_AVPLL_BIT_QUIRK)
158 		reg &= ~(VCO_POWERUP << 4);
159 	else
160 		reg &= ~VCO_POWERUP;
161 	writel_relaxed(reg, vco->base + VCO_CTRL0);
162 }
163 
164 static u8 vco_refdiv[] = { 1, 2, 4, 3 };
165 
166 static unsigned long
167 berlin2_avpll_vco_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
168 {
169 	struct berlin2_avpll_vco *vco = to_avpll_vco(hw);
170 	u32 reg, refdiv, fbdiv;
171 	u64 freq = parent_rate;
172 
173 	/* AVPLL VCO frequency: Fvco = (Fref / refdiv) * fbdiv */
174 	reg = readl_relaxed(vco->base + VCO_CTRL1);
175 	refdiv = (reg & VCO_REFDIV_MASK) >> VCO_REFDIV_SHIFT;
176 	refdiv = vco_refdiv[refdiv];
177 	fbdiv = (reg & VCO_FBDIV_MASK) >> VCO_FBDIV_SHIFT;
178 	freq *= fbdiv;
179 	do_div(freq, refdiv);
180 
181 	return (unsigned long)freq;
182 }
183 
184 static const struct clk_ops berlin2_avpll_vco_ops = {
185 	.is_enabled	= berlin2_avpll_vco_is_enabled,
186 	.enable		= berlin2_avpll_vco_enable,
187 	.disable	= berlin2_avpll_vco_disable,
188 	.recalc_rate	= berlin2_avpll_vco_recalc_rate,
189 };
190 
191 struct clk * __init berlin2_avpll_vco_register(void __iomem *base,
192 			       const char *name, const char *parent_name,
193 			       u8 vco_flags, unsigned long flags)
194 {
195 	struct berlin2_avpll_vco *vco;
196 	struct clk_init_data init;
197 
198 	vco = kzalloc(sizeof(*vco), GFP_KERNEL);
199 	if (!vco)
200 		return ERR_PTR(-ENOMEM);
201 
202 	vco->base = base;
203 	vco->flags = vco_flags;
204 	vco->hw.init = &init;
205 	init.name = name;
206 	init.ops = &berlin2_avpll_vco_ops;
207 	init.parent_names = &parent_name;
208 	init.num_parents = 1;
209 	init.flags = flags;
210 
211 	return clk_register(NULL, &vco->hw);
212 }
213 
214 struct berlin2_avpll_channel {
215 	struct clk_hw hw;
216 	void __iomem *base;
217 	u8 flags;
218 	u8 index;
219 };
220 
221 #define to_avpll_channel(hw) container_of(hw, struct berlin2_avpll_channel, hw)
222 
223 static int berlin2_avpll_channel_is_enabled(struct clk_hw *hw)
224 {
225 	struct berlin2_avpll_channel *ch = to_avpll_channel(hw);
226 	u32 reg;
227 
228 	if (ch->index == 7)
229 		return 1;
230 
231 	reg = readl_relaxed(ch->base + VCO_CTRL10);
232 	reg &= VCO_POWERUP_CH1 << ch->index;
233 
234 	return !!reg;
235 }
236 
237 static int berlin2_avpll_channel_enable(struct clk_hw *hw)
238 {
239 	struct berlin2_avpll_channel *ch = to_avpll_channel(hw);
240 	u32 reg;
241 
242 	reg = readl_relaxed(ch->base + VCO_CTRL10);
243 	reg |= VCO_POWERUP_CH1 << ch->index;
244 	writel_relaxed(reg, ch->base + VCO_CTRL10);
245 
246 	return 0;
247 }
248 
249 static void berlin2_avpll_channel_disable(struct clk_hw *hw)
250 {
251 	struct berlin2_avpll_channel *ch = to_avpll_channel(hw);
252 	u32 reg;
253 
254 	reg = readl_relaxed(ch->base + VCO_CTRL10);
255 	reg &= ~(VCO_POWERUP_CH1 << ch->index);
256 	writel_relaxed(reg, ch->base + VCO_CTRL10);
257 }
258 
259 static const u8 div_hdmi[] = { 1, 2, 4, 6 };
260 static const u8 div_av1[] = { 1, 2, 5, 5 };
261 
262 static unsigned long
263 berlin2_avpll_channel_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
264 {
265 	struct berlin2_avpll_channel *ch = to_avpll_channel(hw);
266 	u32 reg, div_av2, div_av3, divider = 1;
267 	u64 freq = parent_rate;
268 
269 	reg = readl_relaxed(ch->base + VCO_CTRL30);
270 	if ((reg & (VCO_DPLL_CH1_ENABLE << ch->index)) == 0)
271 		goto skip_div;
272 
273 	/*
274 	 * Fch = (Fref * sync2) /
275 	 *    (sync1 * div_hdmi * div_av1 * div_av2 * div_av3)
276 	 */
277 
278 	reg = readl_relaxed(ch->base + VCO_SYNC1n(ch->index));
279 	/* BG2/BG2CDs SYNC1 reg on AVPLL_B channel 1 is shifted by 4 */
280 	if (ch->flags & BERLIN2_AVPLL_BIT_QUIRK && ch->index == 0)
281 		reg >>= 4;
282 	divider = reg & VCO_SYNC1_MASK;
283 
284 	reg = readl_relaxed(ch->base + VCO_SYNC2n(ch->index));
285 	freq *= reg & VCO_SYNC2_MASK;
286 
287 	/* Channel 8 has no dividers */
288 	if (ch->index == 7)
289 		goto skip_div;
290 
291 	/*
292 	 * HDMI divider start at VCO_CTRL11, bit 7; MSB is enable, lower 2 bit
293 	 * determine divider.
294 	 */
295 	reg = readl_relaxed(ch->base + VCO_CTRL11) >> 7;
296 	reg = (reg >> (ch->index * 3));
297 	if (reg & BIT(2))
298 		divider *= div_hdmi[reg & 0x3];
299 
300 	/*
301 	 * AV1 divider start at VCO_CTRL11, bit 28; MSB is enable, lower 2 bit
302 	 * determine divider.
303 	 */
304 	if (ch->index == 0) {
305 		reg = readl_relaxed(ch->base + VCO_CTRL11);
306 		reg >>= 28;
307 	} else {
308 		reg = readl_relaxed(ch->base + VCO_CTRL12);
309 		reg >>= (ch->index-1) * 3;
310 	}
311 	if (reg & BIT(2))
312 		divider *= div_av1[reg & 0x3];
313 
314 	/*
315 	 * AV2 divider start at VCO_CTRL12, bit 18; each 7 bits wide,
316 	 * zero is not a valid value.
317 	 */
318 	if (ch->index < 2) {
319 		reg = readl_relaxed(ch->base + VCO_CTRL12);
320 		reg >>= 18 + (ch->index * 7);
321 	} else if (ch->index < 7) {
322 		reg = readl_relaxed(ch->base + VCO_CTRL13);
323 		reg >>= (ch->index - 2) * 7;
324 	} else {
325 		reg = readl_relaxed(ch->base + VCO_CTRL14);
326 	}
327 	div_av2 = reg & 0x7f;
328 	if (div_av2)
329 		divider *= div_av2;
330 
331 	/*
332 	 * AV3 divider start at VCO_CTRL14, bit 7; each 4 bits wide.
333 	 * AV2/AV3 form a fractional divider, where only specfic values for AV3
334 	 * are allowed. AV3 != 0 divides by AV2/2, AV3=0 is bypass.
335 	 */
336 	if (ch->index < 6) {
337 		reg = readl_relaxed(ch->base + VCO_CTRL14);
338 		reg >>= 7 + (ch->index * 4);
339 	} else {
340 		reg = readl_relaxed(ch->base + VCO_CTRL15);
341 	}
342 	div_av3 = reg & 0xf;
343 	if (div_av2 && div_av3)
344 		freq *= 2;
345 
346 skip_div:
347 	do_div(freq, divider);
348 	return (unsigned long)freq;
349 }
350 
351 static const struct clk_ops berlin2_avpll_channel_ops = {
352 	.is_enabled	= berlin2_avpll_channel_is_enabled,
353 	.enable		= berlin2_avpll_channel_enable,
354 	.disable	= berlin2_avpll_channel_disable,
355 	.recalc_rate	= berlin2_avpll_channel_recalc_rate,
356 };
357 
358 /*
359  * Another nice quirk:
360  * On some production SoCs, AVPLL channels are scrambled with respect
361  * to the channel numbering in the registers but still referenced by
362  * their original channel numbers. We deal with it by having a flag
363  * and a translation table for the index.
364  */
365 static const u8 quirk_index[] __initconst = { 0, 6, 5, 4, 3, 2, 1, 7 };
366 
367 struct clk * __init berlin2_avpll_channel_register(void __iomem *base,
368 			   const char *name, u8 index, const char *parent_name,
369 			   u8 ch_flags, unsigned long flags)
370 {
371 	struct berlin2_avpll_channel *ch;
372 	struct clk_init_data init;
373 
374 	ch = kzalloc(sizeof(*ch), GFP_KERNEL);
375 	if (!ch)
376 		return ERR_PTR(-ENOMEM);
377 
378 	ch->base = base;
379 	if (ch_flags & BERLIN2_AVPLL_SCRAMBLE_QUIRK)
380 		ch->index = quirk_index[index];
381 	else
382 		ch->index = index;
383 
384 	ch->flags = ch_flags;
385 	ch->hw.init = &init;
386 	init.name = name;
387 	init.ops = &berlin2_avpll_channel_ops;
388 	init.parent_names = &parent_name;
389 	init.num_parents = 1;
390 	init.flags = flags;
391 
392 	return clk_register(NULL, &ch->hw);
393 }
394