xref: /linux/drivers/phy/freescale/phy-fsl-samsung-hdmi.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2020 NXP
4  * Copyright 2022 Pengutronix, Lucas Stach <kernel@pengutronix.de>
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/bits.h>
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/delay.h>
12 #include <linux/iopoll.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 
17 #define PHY_REG(reg)		(reg * 4)
18 
19 #define REG01_PMS_P_MASK	GENMASK(3, 0)
20 #define REG03_PMS_S_MASK	GENMASK(7, 4)
21 #define REG12_CK_DIV_MASK	GENMASK(5, 4)
22 
23 #define REG13_TG_CODE_LOW_MASK	GENMASK(7, 0)
24 
25 #define REG14_TOL_MASK		GENMASK(7, 4)
26 #define REG14_RP_CODE_MASK	GENMASK(3, 1)
27 #define REG14_TG_CODE_HIGH_MASK	GENMASK(0, 0)
28 
29 #define REG21_SEL_TX_CK_INV	BIT(7)
30 #define REG21_PMS_S_MASK	GENMASK(3, 0)
31 /*
32  * REG33 does not match the ref manual. According to Sandor Yu from NXP,
33  * "There is a doc issue on the i.MX8MP latest RM"
34  * REG33 is being used per guidance from Sandor
35  */
36 #define REG33_MODE_SET_DONE	BIT(7)
37 #define REG33_FIX_DA		BIT(1)
38 
39 #define REG34_PHY_READY	BIT(7)
40 #define REG34_PLL_LOCK		BIT(6)
41 #define REG34_PHY_CLK_READY	BIT(5)
42 
43 #ifndef MHZ
44 #define MHZ	(1000UL * 1000UL)
45 #endif
46 
47 #define PHY_PLL_DIV_REGS_NUM 7
48 
49 struct phy_config {
50 	u32	pixclk;
51 	u8	pll_div_regs[PHY_PLL_DIV_REGS_NUM];
52 };
53 
54 /*
55  * The calculated_phy_pll_cfg only handles integer divider for PMS,
56  * meaning the last four entries will be fixed, but the first three will
57  * be calculated by the PMS calculator.
58  */
59 static struct phy_config calculated_phy_pll_cfg = {
60 	.pixclk = 0,
61 	.pll_div_regs = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x00 },
62 };
63 
64 /* The lookup table contains values for which the fractional divder is used */
65 static const struct phy_config phy_pll_cfg[] = {
66 	{
67 		.pixclk = 22250000,
68 		.pll_div_regs = { 0xd1, 0x4b, 0xf1, 0x89, 0x88, 0x80, 0x40 },
69 	}, {
70 		.pixclk = 23750000,
71 		.pll_div_regs = { 0xd1, 0x50, 0xf1, 0x86, 0x85, 0x80, 0x40 },
72 	}, {
73 		.pixclk = 24024000,
74 		.pll_div_regs = { 0xd1, 0x50, 0xf1, 0x99, 0x02, 0x80, 0x40 },
75 	}, {
76 		.pixclk = 25175000,
77 		.pll_div_regs = { 0xd1, 0x54, 0xfc, 0xcc, 0x91, 0x80, 0x40 },
78 	},  {
79 		.pixclk = 26750000,
80 		.pll_div_regs = { 0xd1, 0x5a, 0xf2, 0x89, 0x88, 0x80, 0x40 },
81 	},  {
82 		.pixclk = 27027000,
83 		.pll_div_regs = { 0xd1, 0x5a, 0xf2, 0xfd, 0x0c, 0x80, 0x40 },
84 	}, {
85 		.pixclk = 29500000,
86 		.pll_div_regs = { 0xd1, 0x62, 0xf4, 0x95, 0x08, 0x80, 0x40 },
87 	}, {
88 		.pixclk = 30750000,
89 		.pll_div_regs = { 0xd1, 0x66, 0xf4, 0x82, 0x01, 0x88, 0x45 },
90 	}, {
91 		.pixclk = 30888000,
92 		.pll_div_regs = { 0xd1, 0x66, 0xf4, 0x99, 0x18, 0x88, 0x45 },
93 	}, {
94 		.pixclk = 33750000,
95 		.pll_div_regs = { 0xd1, 0x70, 0xf4, 0x82, 0x01, 0x80, 0x40 },
96 	}, {
97 		.pixclk = 35000000,
98 		.pll_div_regs = { 0xd1, 0x58, 0xb8, 0x8b, 0x88, 0x80, 0x40 },
99 	},  {
100 		.pixclk = 36036000,
101 		.pll_div_regs = { 0xd1, 0x5a, 0xb2, 0xfd, 0x0c, 0x80, 0x40 },
102 	}, {
103 		.pixclk = 43243200,
104 		.pll_div_regs = { 0xd1, 0x5a, 0x92, 0xfd, 0x0c, 0x80, 0x40 },
105 	}, {
106 		.pixclk = 44500000,
107 		.pll_div_regs = { 0xd1, 0x5c, 0x92, 0x98, 0x11, 0x84, 0x41 },
108 	}, {
109 		.pixclk = 47000000,
110 		.pll_div_regs = { 0xd1, 0x62, 0x94, 0x95, 0x82, 0x80, 0x40 },
111 	}, {
112 		.pixclk = 47500000,
113 		.pll_div_regs = { 0xd1, 0x63, 0x96, 0xa1, 0x82, 0x80, 0x40 },
114 	}, {
115 		.pixclk = 50349650,
116 		.pll_div_regs = { 0xd1, 0x54, 0x7c, 0xc3, 0x8f, 0x80, 0x40 },
117 	}, {
118 		.pixclk = 53250000,
119 		.pll_div_regs = { 0xd1, 0x58, 0x72, 0x84, 0x03, 0x82, 0x41 },
120 	}, {
121 		.pixclk = 53500000,
122 		.pll_div_regs = { 0xd1, 0x5a, 0x72, 0x89, 0x88, 0x80, 0x40 },
123 	},  {
124 		.pixclk = 54054000,
125 		.pll_div_regs = { 0xd1, 0x5a, 0x72, 0xfd, 0x0c, 0x80, 0x40 },
126 	}, {
127 		.pixclk = 59000000,
128 		.pll_div_regs = { 0xd1, 0x62, 0x74, 0x95, 0x08, 0x80, 0x40 },
129 	}, {
130 		.pixclk = 59340659,
131 		.pll_div_regs = { 0xd1, 0x62, 0x74, 0xdb, 0x52, 0x88, 0x47 },
132 	},  {
133 		.pixclk = 61500000,
134 		.pll_div_regs = { 0xd1, 0x66, 0x74, 0x82, 0x01, 0x88, 0x45 },
135 	}, {
136 		.pixclk = 63500000,
137 		.pll_div_regs = { 0xd1, 0x69, 0x74, 0x89, 0x08, 0x80, 0x40 },
138 	}, {
139 		.pixclk = 67500000,
140 		.pll_div_regs = { 0xd1, 0x54, 0x52, 0x87, 0x03, 0x80, 0x40 },
141 	}, {
142 		.pixclk = 70000000,
143 		.pll_div_regs = { 0xd1, 0x58, 0x58, 0x8b, 0x88, 0x80, 0x40 },
144 	},  {
145 		.pixclk = 72072000,
146 		.pll_div_regs = { 0xd1, 0x5a, 0x52, 0xfd, 0x0c, 0x80, 0x40 },
147 	}, {
148 		.pixclk = 74176000,
149 		.pll_div_regs = { 0xd1, 0x5d, 0x58, 0xdb, 0xA2, 0x88, 0x41 },
150 	}, {
151 		.pixclk = 74250000,
152 		.pll_div_regs = { 0xd1, 0x5c, 0x52, 0x90, 0x0d, 0x84, 0x41 },
153 	}, {
154 		.pixclk = 78500000,
155 		.pll_div_regs = { 0xd1, 0x62, 0x54, 0x87, 0x01, 0x80, 0x40 },
156 	},  {
157 		.pixclk = 82000000,
158 		.pll_div_regs = { 0xd1, 0x66, 0x54, 0x82, 0x01, 0x88, 0x45 },
159 	}, {
160 		.pixclk = 82500000,
161 		.pll_div_regs = { 0xd1, 0x67, 0x54, 0x88, 0x01, 0x90, 0x49 },
162 	}, {
163 		.pixclk = 89000000,
164 		.pll_div_regs = { 0xd1, 0x70, 0x54, 0x84, 0x83, 0x80, 0x40 },
165 	}, {
166 		.pixclk = 90000000,
167 		.pll_div_regs = { 0xd1, 0x70, 0x54, 0x82, 0x01, 0x80, 0x40 },
168 	}, {
169 		.pixclk = 94000000,
170 		.pll_div_regs = { 0xd1, 0x4e, 0x32, 0xa7, 0x10, 0x80, 0x40 },
171 	}, {
172 		.pixclk = 95000000,
173 		.pll_div_regs = { 0xd1, 0x50, 0x31, 0x86, 0x85, 0x80, 0x40 },
174 	}, {
175 		.pixclk = 98901099,
176 		.pll_div_regs = { 0xd1, 0x52, 0x3a, 0xdb, 0x4c, 0x88, 0x47 },
177 	}, {
178 		.pixclk = 99000000,
179 		.pll_div_regs = { 0xd1, 0x52, 0x32, 0x82, 0x01, 0x88, 0x47 },
180 	}, {
181 		.pixclk = 100699300,
182 		.pll_div_regs = { 0xd1, 0x54, 0x3c, 0xc3, 0x8f, 0x80, 0x40 },
183 	},  {
184 		.pixclk = 102500000,
185 		.pll_div_regs = { 0xd1, 0x55, 0x32, 0x8c, 0x05, 0x90, 0x4b },
186 	}, {
187 		.pixclk = 104750000,
188 		.pll_div_regs = { 0xd1, 0x57, 0x32, 0x98, 0x07, 0x90, 0x49 },
189 	}, {
190 		.pixclk = 106500000,
191 		.pll_div_regs = { 0xd1, 0x58, 0x32, 0x84, 0x03, 0x82, 0x41 },
192 	}, {
193 		.pixclk = 107000000,
194 		.pll_div_regs = { 0xd1, 0x5a, 0x32, 0x89, 0x88, 0x80, 0x40 },
195 	},  {
196 		.pixclk = 108108000,
197 		.pll_div_regs = { 0xd1, 0x5a, 0x32, 0xfd, 0x0c, 0x80, 0x40 },
198 	}, {
199 		.pixclk = 118000000,
200 		.pll_div_regs = { 0xd1, 0x62, 0x34, 0x95, 0x08, 0x80, 0x40 },
201 	},  {
202 		.pixclk = 123000000,
203 		.pll_div_regs = { 0xd1, 0x66, 0x34, 0x82, 0x01, 0x88, 0x45 },
204 	}, {
205 		.pixclk = 127000000,
206 		.pll_div_regs = { 0xd1, 0x69, 0x34, 0x89, 0x08, 0x80, 0x40 },
207 	}, {
208 		.pixclk = 135000000,
209 		.pll_div_regs = { 0xd1, 0x70, 0x34, 0x82, 0x01, 0x80, 0x40 },
210 	}, {
211 		.pixclk = 135580000,
212 		.pll_div_regs = { 0xd1, 0x71, 0x39, 0xe9, 0x82, 0x9c, 0x5b },
213 	}, {
214 		.pixclk = 137520000,
215 		.pll_div_regs = { 0xd1, 0x72, 0x38, 0x99, 0x10, 0x85, 0x41 },
216 	}, {
217 		.pixclk = 138750000,
218 		.pll_div_regs = { 0xd1, 0x73, 0x35, 0x88, 0x05, 0x90, 0x4d },
219 	}, {
220 		.pixclk = 140000000,
221 		.pll_div_regs = { 0xd1, 0x75, 0x36, 0xa7, 0x90, 0x80, 0x40 },
222 	},  {
223 		.pixclk = 148352000,
224 		.pll_div_regs = { 0xd1, 0x7b, 0x35, 0xdb, 0x39, 0x90, 0x45 },
225 	}, {
226 		.pixclk = 148500000,
227 		.pll_div_regs = { 0xd1, 0x7b, 0x35, 0x84, 0x03, 0x90, 0x45 },
228 	}, {
229 		.pixclk = 154000000,
230 		.pll_div_regs = { 0xd1, 0x40, 0x18, 0x83, 0x01, 0x00, 0x40 },
231 	}, {
232 		.pixclk = 157000000,
233 		.pll_div_regs = { 0xd1, 0x41, 0x11, 0xa7, 0x14, 0x80, 0x40 },
234 	}, {
235 		.pixclk = 160000000,
236 		.pll_div_regs = { 0xd1, 0x42, 0x12, 0xa1, 0x20, 0x80, 0x40 },
237 	}, {
238 		.pixclk = 162000000,
239 		.pll_div_regs = { 0xd1, 0x43, 0x18, 0x8b, 0x08, 0x96, 0x55 },
240 	}, {
241 		.pixclk = 164000000,
242 		.pll_div_regs = { 0xd1, 0x45, 0x11, 0x83, 0x82, 0x90, 0x4b },
243 	}, {
244 		.pixclk = 165000000,
245 		.pll_div_regs = { 0xd1, 0x45, 0x11, 0x84, 0x81, 0x90, 0x4b },
246 	}, {
247 		.pixclk = 185625000,
248 		.pll_div_regs = { 0xd1, 0x4e, 0x12, 0x9a, 0x95, 0x80, 0x40 },
249 	}, {
250 		.pixclk = 188000000,
251 		.pll_div_regs = { 0xd1, 0x4e, 0x12, 0xa7, 0x10, 0x80, 0x40 },
252 	}, {
253 		.pixclk = 198000000,
254 		.pll_div_regs = { 0xd1, 0x52, 0x12, 0x82, 0x01, 0x88, 0x47 },
255 	}, {
256 		.pixclk = 205000000,
257 		.pll_div_regs = { 0xd1, 0x55, 0x12, 0x8c, 0x05, 0x90, 0x4b },
258 	}, {
259 		.pixclk = 209500000,
260 		.pll_div_regs = { 0xd1, 0x57, 0x12, 0x98, 0x07, 0x90, 0x49 },
261 	}, {
262 		.pixclk = 213000000,
263 		.pll_div_regs = { 0xd1, 0x58, 0x12, 0x84, 0x03, 0x82, 0x41 },
264 	}, {
265 		.pixclk = 216216000,
266 		.pll_div_regs = { 0xd1, 0x5a, 0x12, 0xfd, 0x0c, 0x80, 0x40 },
267 	},  {
268 		.pixclk = 254000000,
269 		.pll_div_regs = { 0xd1, 0x69, 0x14, 0x89, 0x08, 0x80, 0x40 },
270 	}, {
271 		.pixclk = 277500000,
272 		.pll_div_regs = { 0xd1, 0x73, 0x15, 0x88, 0x05, 0x90, 0x4d },
273 	},  {
274 		.pixclk = 297000000,
275 		.pll_div_regs = { 0xd1, 0x7b, 0x15, 0x84, 0x03, 0x90, 0x45 },
276 	},
277 };
278 
279 struct reg_settings {
280 	u8 reg;
281 	u8 val;
282 };
283 
284 static const struct reg_settings common_phy_cfg[] = {
285 	{ PHY_REG(0), 0x00 },
286 	/* PHY_REG(1-7) pix clk specific */
287 	{ PHY_REG(8), 0x4f }, { PHY_REG(9), 0x30 },
288 	{ PHY_REG(10), 0x33 }, { PHY_REG(11), 0x65 },
289 	/* REG12 pixclk specific */
290 	/* REG13 pixclk specific */
291 	/* REG14 pixclk specific */
292 	{ PHY_REG(15), 0x80 }, { PHY_REG(16), 0x6c },
293 	{ PHY_REG(17), 0xf2 }, { PHY_REG(18), 0x67 },
294 	{ PHY_REG(19), 0x00 }, { PHY_REG(20), 0x10 },
295 	/* REG21 pixclk specific */
296 	{ PHY_REG(22), 0x30 }, { PHY_REG(23), 0x32 },
297 	{ PHY_REG(24), 0x60 }, { PHY_REG(25), 0x8f },
298 	{ PHY_REG(26), 0x00 }, { PHY_REG(27), 0x00 },
299 	{ PHY_REG(28), 0x08 }, { PHY_REG(29), 0x00 },
300 	{ PHY_REG(30), 0x00 }, { PHY_REG(31), 0x00 },
301 	{ PHY_REG(32), 0x00 }, { PHY_REG(33), 0x80 },
302 	{ PHY_REG(34), 0x00 }, { PHY_REG(35), 0x00 },
303 	{ PHY_REG(36), 0x00 }, { PHY_REG(37), 0x00 },
304 	{ PHY_REG(38), 0x00 }, { PHY_REG(39), 0x00 },
305 	{ PHY_REG(40), 0x00 }, { PHY_REG(41), 0xe0 },
306 	{ PHY_REG(42), 0x83 }, { PHY_REG(43), 0x0f },
307 	{ PHY_REG(44), 0x3E }, { PHY_REG(45), 0xf8 },
308 	{ PHY_REG(46), 0x00 }, { PHY_REG(47), 0x00 }
309 };
310 
311 struct fsl_samsung_hdmi_phy {
312 	struct device *dev;
313 	void __iomem *regs;
314 	struct clk *apbclk;
315 	struct clk *refclk;
316 
317 	/* clk provider */
318 	struct clk_hw hw;
319 	const struct phy_config *cur_cfg;
320 };
321 
322 static inline struct fsl_samsung_hdmi_phy *
323 to_fsl_samsung_hdmi_phy(struct clk_hw *hw)
324 {
325 	return container_of(hw, struct fsl_samsung_hdmi_phy, hw);
326 }
327 
328 static void
329 fsl_samsung_hdmi_phy_configure_pll_lock_det(struct fsl_samsung_hdmi_phy *phy,
330 					    const struct phy_config *cfg)
331 {
332 	u32 pclk = cfg->pixclk;
333 	u32 fld_tg_code;
334 	u32 pclk_khz;
335 	u8 div = 1;
336 
337 	switch (cfg->pixclk) {
338 	case  22250000 ...  47500000:
339 		div = 1;
340 		break;
341 	case  50349650 ...  99000000:
342 		div = 2;
343 		break;
344 	case 100699300 ... 198000000:
345 		div = 4;
346 		break;
347 	case 205000000 ... 297000000:
348 		div = 8;
349 		break;
350 	}
351 
352 	writeb(FIELD_PREP(REG12_CK_DIV_MASK, ilog2(div)), phy->regs + PHY_REG(12));
353 
354 	/*
355 	 * Calculation for the frequency lock detector target code (fld_tg_code)
356 	 * is based on reference manual register description of PHY_REG13
357 	 * (13.10.3.1.14.2):
358 	 *   1st) Calculate int_pllclk which is determinded by FLD_CK_DIV
359 	 *   2nd) Increase resolution to avoid rounding issues
360 	 *   3th) Do the div (256 / Freq. of int_pllclk) * 24
361 	 *   4th) Reduce the resolution and always round up since the NXP
362 	 *        settings rounding up always too. TODO: Check if that is
363 	 *        correct.
364 	 */
365 	pclk /= div;
366 	pclk_khz = pclk / 1000;
367 	fld_tg_code = 256 * 1000 * 1000 / pclk_khz * 24;
368 	fld_tg_code = DIV_ROUND_UP(fld_tg_code, 1000);
369 
370 	/* FLD_TOL and FLD_RP_CODE taken from downstream driver */
371 	writeb(FIELD_PREP(REG13_TG_CODE_LOW_MASK, fld_tg_code),
372 	       phy->regs + PHY_REG(13));
373 	writeb(FIELD_PREP(REG14_TOL_MASK, 2) |
374 	       FIELD_PREP(REG14_RP_CODE_MASK, 2) |
375 	       FIELD_PREP(REG14_TG_CODE_HIGH_MASK, fld_tg_code >> 8),
376 	       phy->regs + PHY_REG(14));
377 }
378 
379 static unsigned long fsl_samsung_hdmi_phy_find_pms(unsigned long fout, u8 *p, u16 *m, u8 *s)
380 {
381 	unsigned long best_freq = 0;
382 	u32 min_delta = 0xffffffff;
383 	u8 _p, best_p;
384 	u16 _m, best_m;
385 	u8 _s, best_s;
386 
387 	/*
388 	 * Figure 13-78 of the reference manual states the PLL should be TMDS x 5
389 	 * while the TMDS_CLKO should be the PLL / 5.  So to calculate the PLL,
390 	 * take the pix clock x 5, then return the value of the PLL / 5.
391 	 */
392 	fout *= 5;
393 
394 	/* The ref manual states the values of 'P' range from 1 to 11 */
395 	for (_p = 1; _p <= 11; ++_p) {
396 		for (_s = 1; _s <= 16; ++_s) {
397 			u64 tmp;
398 			u32 delta;
399 
400 			/* s must be one or even */
401 			if (_s > 1 && (_s & 0x01) == 1)
402 				_s++;
403 
404 			/* _s cannot be 14 per the TRM */
405 			if (_s == 14)
406 				continue;
407 
408 			/*
409 			 * TODO: Ref Manual doesn't state the range of _m
410 			 * so this should be further refined if possible.
411 			 * This range was set based on the original values
412 			 * in the lookup table
413 			 */
414 			tmp = (u64)fout * (_p * _s);
415 			do_div(tmp, 24 * MHZ);
416 			_m = tmp;
417 			if (_m < 0x30 || _m > 0x7b)
418 				continue;
419 
420 			/*
421 			 * Rev 2 of the Ref Manual states the
422 			 * VCO can range between 750MHz and
423 			 * 3GHz. The VCO is assumed to be
424 			 * Fvco = (M * f_ref) / P,
425 			 * where f_ref is 24MHz.
426 			 */
427 			tmp = (u64)_m * 24 * MHZ;
428 			do_div(tmp, _p);
429 			if (tmp < 750 * MHZ ||
430 			    tmp > 3000 * MHZ)
431 				continue;
432 
433 			/* Final frequency after post-divider */
434 			do_div(tmp, _s);
435 
436 			delta = abs(fout - tmp);
437 			if (delta < min_delta) {
438 				best_p = _p;
439 				best_s = _s;
440 				best_m = _m;
441 				min_delta = delta;
442 				best_freq = tmp;
443 			}
444 		}
445 	}
446 
447 	if (best_freq) {
448 		*p = best_p;
449 		*m = best_m;
450 		*s = best_s;
451 	}
452 
453 	return best_freq / 5;
454 }
455 
456 static int fsl_samsung_hdmi_phy_configure(struct fsl_samsung_hdmi_phy *phy,
457 					  const struct phy_config *cfg)
458 {
459 	int i, ret;
460 	u8 val;
461 
462 	/* HDMI PHY init */
463 	writeb(REG33_FIX_DA, phy->regs + PHY_REG(33));
464 
465 	/* common PHY registers */
466 	for (i = 0; i < ARRAY_SIZE(common_phy_cfg); i++)
467 		writeb(common_phy_cfg[i].val, phy->regs + common_phy_cfg[i].reg);
468 
469 	/* set individual PLL registers PHY_REG1 ... PHY_REG7 */
470 	for (i = 0; i < PHY_PLL_DIV_REGS_NUM; i++)
471 		writeb(cfg->pll_div_regs[i], phy->regs + PHY_REG(1) + i * 4);
472 
473 	/* High nibble of PHY_REG3 and low nibble of PHY_REG21 both contain 'S' */
474 	writeb(REG21_SEL_TX_CK_INV | FIELD_PREP(REG21_PMS_S_MASK,
475 	       cfg->pll_div_regs[2] >> 4), phy->regs + PHY_REG(21));
476 
477 	fsl_samsung_hdmi_phy_configure_pll_lock_det(phy, cfg);
478 
479 	writeb(REG33_FIX_DA | REG33_MODE_SET_DONE, phy->regs + PHY_REG(33));
480 
481 	ret = readb_poll_timeout(phy->regs + PHY_REG(34), val,
482 				 val & REG34_PLL_LOCK, 50, 20000);
483 	if (ret)
484 		dev_err(phy->dev, "PLL failed to lock\n");
485 
486 	return ret;
487 }
488 
489 static unsigned long phy_clk_recalc_rate(struct clk_hw *hw,
490 					 unsigned long parent_rate)
491 {
492 	struct fsl_samsung_hdmi_phy *phy = to_fsl_samsung_hdmi_phy(hw);
493 
494 	if (!phy->cur_cfg)
495 		return 74250000;
496 
497 	return phy->cur_cfg->pixclk;
498 }
499 
500 /* Helper function to lookup the available fractional-divider rate */
501 static const struct phy_config *fsl_samsung_hdmi_phy_lookup_rate(unsigned long rate)
502 {
503 	int i;
504 
505 	/* Search the lookup table */
506 	for (i = ARRAY_SIZE(phy_pll_cfg) - 1; i >= 0; i--)
507 		if (phy_pll_cfg[i].pixclk <= rate)
508 			break;
509 
510 	return &phy_pll_cfg[i];
511 }
512 
513 static void fsl_samsung_hdmi_calculate_phy(struct phy_config *cal_phy, unsigned long rate,
514 				    u8 p, u16 m, u8 s)
515 {
516 	cal_phy->pixclk = rate;
517 	cal_phy->pll_div_regs[0] = FIELD_PREP(REG01_PMS_P_MASK, p);
518 	cal_phy->pll_div_regs[1] = m;
519 	cal_phy->pll_div_regs[2] = FIELD_PREP(REG03_PMS_S_MASK, s-1);
520 	/* pll_div_regs 3-6 are fixed and pre-defined already */
521 }
522 
523 static u32 fsl_samsung_hdmi_phy_get_closest_rate(unsigned long rate,
524 						 u32 int_div_clk, u32 frac_div_clk)
525 {
526 	/* Calculate the absolute value of the differences and return whichever is closest */
527 	if (abs((long)rate - (long)int_div_clk) < abs((long)(rate - (long)frac_div_clk)))
528 		return int_div_clk;
529 
530 	return frac_div_clk;
531 }
532 
533 static long phy_clk_round_rate(struct clk_hw *hw,
534 			       unsigned long rate, unsigned long *parent_rate)
535 {
536 	const struct phy_config *fract_div_phy;
537 	u32 int_div_clk;
538 	u16 m;
539 	u8 p, s;
540 
541 	/* If the clock is out of range return error instead of searching */
542 	if (rate > 297000000 || rate < 22250000)
543 		return -EINVAL;
544 
545 	/* Search the fractional divider lookup table */
546 	fract_div_phy = fsl_samsung_hdmi_phy_lookup_rate(rate);
547 
548 	/* If the rate is an exact match, return that value */
549 	if (rate == fract_div_phy->pixclk)
550 		return fract_div_phy->pixclk;
551 
552 	/* If the exact match isn't found, calculate the integer divider */
553 	int_div_clk = fsl_samsung_hdmi_phy_find_pms(rate, &p, &m, &s);
554 
555 	/* If the int_div_clk rate is an exact match, return that value */
556 	if (int_div_clk == rate)
557 		return int_div_clk;
558 
559 	/* If neither rate is an exact match, use the value from the LUT */
560 	return fract_div_phy->pixclk;
561 }
562 
563 static int phy_use_fract_div(struct fsl_samsung_hdmi_phy *phy, const struct phy_config *fract_div_phy)
564 {
565 	phy->cur_cfg = fract_div_phy;
566 	dev_dbg(phy->dev, "fsl_samsung_hdmi_phy: using fractional divider rate = %u\n",
567 		phy->cur_cfg->pixclk);
568 	return fsl_samsung_hdmi_phy_configure(phy, phy->cur_cfg);
569 }
570 
571 static int phy_use_integer_div(struct fsl_samsung_hdmi_phy *phy,
572 			       const struct phy_config *int_div_clk)
573 {
574 	phy->cur_cfg  = &calculated_phy_pll_cfg;
575 	dev_dbg(phy->dev, "fsl_samsung_hdmi_phy: integer divider rate = %u\n",
576 		phy->cur_cfg->pixclk);
577 	return fsl_samsung_hdmi_phy_configure(phy, phy->cur_cfg);
578 }
579 
580 static int phy_clk_set_rate(struct clk_hw *hw,
581 			    unsigned long rate, unsigned long parent_rate)
582 {
583 	struct fsl_samsung_hdmi_phy *phy = to_fsl_samsung_hdmi_phy(hw);
584 	const struct phy_config *fract_div_phy;
585 	u32 int_div_clk;
586 	u16 m;
587 	u8 p, s;
588 
589 	/* Search the fractional divider lookup table */
590 	fract_div_phy = fsl_samsung_hdmi_phy_lookup_rate(rate);
591 
592 	/* If the rate is an exact match, use that value */
593 	if (fract_div_phy->pixclk == rate)
594 		return phy_use_fract_div(phy, fract_div_phy);
595 
596 	/*
597 	 * If the rate from the fractional divider is not exact, check the integer divider,
598 	 * and use it if that value is an exact match.
599 	 */
600 	int_div_clk = fsl_samsung_hdmi_phy_find_pms(rate, &p, &m, &s);
601 	fsl_samsung_hdmi_calculate_phy(&calculated_phy_pll_cfg, int_div_clk, p, m, s);
602 	if (int_div_clk == rate)
603 		return phy_use_integer_div(phy, &calculated_phy_pll_cfg);
604 
605 	/*
606 	 * Compare the difference between the integer clock and the fractional clock against
607 	 * the desired clock and which whichever is closest.
608 	 */
609 	if (fsl_samsung_hdmi_phy_get_closest_rate(rate, int_div_clk,
610 						  fract_div_phy->pixclk) == fract_div_phy->pixclk)
611 		return phy_use_fract_div(phy, fract_div_phy);
612 	else
613 		return phy_use_integer_div(phy, &calculated_phy_pll_cfg);
614 }
615 
616 static const struct clk_ops phy_clk_ops = {
617 	.recalc_rate = phy_clk_recalc_rate,
618 	.round_rate = phy_clk_round_rate,
619 	.set_rate = phy_clk_set_rate,
620 };
621 
622 static int phy_clk_register(struct fsl_samsung_hdmi_phy *phy)
623 {
624 	struct device *dev = phy->dev;
625 	struct device_node *np = dev->of_node;
626 	struct clk_init_data init;
627 	const char *parent_name;
628 	struct clk *phyclk;
629 	int ret;
630 
631 	parent_name = __clk_get_name(phy->refclk);
632 
633 	init.parent_names = &parent_name;
634 	init.num_parents = 1;
635 	init.flags = 0;
636 	init.name = "hdmi_pclk";
637 	init.ops = &phy_clk_ops;
638 
639 	phy->hw.init = &init;
640 
641 	phyclk = devm_clk_register(dev, &phy->hw);
642 	if (IS_ERR(phyclk))
643 		return dev_err_probe(dev, PTR_ERR(phyclk),
644 				     "failed to register clock\n");
645 
646 	ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, phyclk);
647 	if (ret)
648 		return dev_err_probe(dev, ret,
649 				     "failed to register clock provider\n");
650 
651 	return 0;
652 }
653 
654 static int fsl_samsung_hdmi_phy_probe(struct platform_device *pdev)
655 {
656 	struct fsl_samsung_hdmi_phy *phy;
657 	int ret;
658 
659 	phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
660 	if (!phy)
661 		return -ENOMEM;
662 
663 	platform_set_drvdata(pdev, phy);
664 	phy->dev = &pdev->dev;
665 
666 	phy->regs = devm_platform_ioremap_resource(pdev, 0);
667 	if (IS_ERR(phy->regs))
668 		return PTR_ERR(phy->regs);
669 
670 	phy->apbclk = devm_clk_get(phy->dev, "apb");
671 	if (IS_ERR(phy->apbclk))
672 		return dev_err_probe(phy->dev, PTR_ERR(phy->apbclk),
673 				     "failed to get apb clk\n");
674 
675 	phy->refclk = devm_clk_get(phy->dev, "ref");
676 	if (IS_ERR(phy->refclk))
677 		return dev_err_probe(phy->dev, PTR_ERR(phy->refclk),
678 				     "failed to get ref clk\n");
679 
680 	ret = clk_prepare_enable(phy->apbclk);
681 	if (ret) {
682 		dev_err(phy->dev, "failed to enable apbclk\n");
683 		return ret;
684 	}
685 
686 	pm_runtime_get_noresume(phy->dev);
687 	pm_runtime_set_active(phy->dev);
688 	pm_runtime_enable(phy->dev);
689 
690 	ret = phy_clk_register(phy);
691 	if (ret) {
692 		dev_err(&pdev->dev, "register clk failed\n");
693 		goto register_clk_failed;
694 	}
695 
696 	pm_runtime_put(phy->dev);
697 
698 	return 0;
699 
700 register_clk_failed:
701 	clk_disable_unprepare(phy->apbclk);
702 
703 	return ret;
704 }
705 
706 static void fsl_samsung_hdmi_phy_remove(struct platform_device *pdev)
707 {
708 	of_clk_del_provider(pdev->dev.of_node);
709 }
710 
711 static int __maybe_unused fsl_samsung_hdmi_phy_suspend(struct device *dev)
712 {
713 	struct fsl_samsung_hdmi_phy *phy = dev_get_drvdata(dev);
714 
715 	clk_disable_unprepare(phy->apbclk);
716 
717 	return 0;
718 }
719 
720 static int __maybe_unused fsl_samsung_hdmi_phy_resume(struct device *dev)
721 {
722 	struct fsl_samsung_hdmi_phy *phy = dev_get_drvdata(dev);
723 	int ret = 0;
724 
725 	ret = clk_prepare_enable(phy->apbclk);
726 	if (ret) {
727 		dev_err(phy->dev, "failed to enable apbclk\n");
728 		return ret;
729 	}
730 
731 	if (phy->cur_cfg)
732 		ret = fsl_samsung_hdmi_phy_configure(phy, phy->cur_cfg);
733 
734 	return ret;
735 
736 }
737 
738 static DEFINE_RUNTIME_DEV_PM_OPS(fsl_samsung_hdmi_phy_pm_ops,
739 				 fsl_samsung_hdmi_phy_suspend,
740 				 fsl_samsung_hdmi_phy_resume, NULL);
741 
742 static const struct of_device_id fsl_samsung_hdmi_phy_of_match[] = {
743 	{
744 		.compatible = "fsl,imx8mp-hdmi-phy",
745 	}, {
746 		/* sentinel */
747 	}
748 };
749 MODULE_DEVICE_TABLE(of, fsl_samsung_hdmi_phy_of_match);
750 
751 static struct platform_driver fsl_samsung_hdmi_phy_driver = {
752 	.probe = fsl_samsung_hdmi_phy_probe,
753 	.remove = fsl_samsung_hdmi_phy_remove,
754 	.driver = {
755 		.name = "fsl-samsung-hdmi-phy",
756 		.of_match_table = fsl_samsung_hdmi_phy_of_match,
757 		.pm = pm_ptr(&fsl_samsung_hdmi_phy_pm_ops),
758 	},
759 };
760 module_platform_driver(fsl_samsung_hdmi_phy_driver);
761 
762 MODULE_AUTHOR("Sandor Yu <Sandor.yu@nxp.com>");
763 MODULE_DESCRIPTION("SAMSUNG HDMI 2.0 Transmitter PHY Driver");
764 MODULE_LICENSE("GPL");
765