1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright: 2017-2018 Cadence Design Systems, Inc.
4 */
5
6 #include <linux/bitfield.h>
7 #include <linux/bitops.h>
8 #include <linux/clk.h>
9 #include <linux/io.h>
10 #include <linux/iopoll.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/platform_device.h>
14 #include <linux/reset.h>
15
16 #include <linux/phy/phy.h>
17 #include <linux/phy/phy-mipi-dphy.h>
18
19 #define REG_WAKEUP_TIME_NS 800
20 #define DPHY_PLL_RATE_HZ 108000000
21 #define POLL_TIMEOUT_US 1000
22
23 /* DPHY registers */
24 #define DPHY_PMA_CMN(reg) (reg)
25 #define DPHY_PMA_LCLK(reg) (0x100 + (reg))
26 #define DPHY_PMA_LDATA(lane, reg) (0x200 + ((lane) * 0x100) + (reg))
27 #define DPHY_PMA_RCLK(reg) (0x600 + (reg))
28 #define DPHY_PMA_RDATA(lane, reg) (0x700 + ((lane) * 0x100) + (reg))
29 #define DPHY_PCS(reg) (0xb00 + (reg))
30
31 #define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
32 #define DPHY_CMN_SSM_EN BIT(0)
33 #define DPHY_CMN_TX_MODE_EN BIT(9)
34
35 #define DPHY_CMN_PWM DPHY_PMA_CMN(0x40)
36 #define DPHY_CMN_PWM_DIV(x) ((x) << 20)
37 #define DPHY_CMN_PWM_LOW(x) ((x) << 10)
38 #define DPHY_CMN_PWM_HIGH(x) (x)
39
40 #define DPHY_CMN_FBDIV DPHY_PMA_CMN(0x4c)
41 #define DPHY_CMN_FBDIV_VAL(low, high) (((high) << 11) | ((low) << 22))
42 #define DPHY_CMN_FBDIV_FROM_REG (BIT(10) | BIT(21))
43
44 #define DPHY_CMN_OPIPDIV DPHY_PMA_CMN(0x50)
45 #define DPHY_CMN_IPDIV_FROM_REG BIT(0)
46 #define DPHY_CMN_IPDIV(x) ((x) << 1)
47 #define DPHY_CMN_OPDIV_FROM_REG BIT(6)
48 #define DPHY_CMN_OPDIV(x) ((x) << 7)
49
50 #define DPHY_BAND_CFG DPHY_PCS(0x0)
51 #define DPHY_BAND_CFG_LEFT_BAND GENMASK(4, 0)
52 #define DPHY_BAND_CFG_RIGHT_BAND GENMASK(9, 5)
53
54 #define DPHY_PSM_CFG DPHY_PCS(0x4)
55 #define DPHY_PSM_CFG_FROM_REG BIT(0)
56 #define DPHY_PSM_CLK_DIV(x) ((x) << 1)
57
58 #define DSI_HBP_FRAME_OVERHEAD 12
59 #define DSI_HSA_FRAME_OVERHEAD 14
60 #define DSI_HFP_FRAME_OVERHEAD 6
61 #define DSI_HSS_VSS_VSE_FRAME_OVERHEAD 4
62 #define DSI_BLANKING_FRAME_OVERHEAD 6
63 #define DSI_NULL_FRAME_OVERHEAD 6
64 #define DSI_EOT_PKT_SIZE 4
65
66 #define DPHY_TX_J721E_WIZ_PLL_CTRL 0xF04
67 #define DPHY_TX_J721E_WIZ_STATUS 0xF08
68 #define DPHY_TX_J721E_WIZ_RST_CTRL 0xF0C
69 #define DPHY_TX_J721E_WIZ_PSM_FREQ 0xF10
70
71 #define DPHY_TX_J721E_WIZ_IPDIV GENMASK(4, 0)
72 #define DPHY_TX_J721E_WIZ_OPDIV GENMASK(13, 8)
73 #define DPHY_TX_J721E_WIZ_FBDIV GENMASK(25, 16)
74 #define DPHY_TX_J721E_WIZ_LANE_RSTB BIT(31)
75 #define DPHY_TX_WIZ_PLL_LOCK BIT(31)
76 #define DPHY_TX_WIZ_O_CMN_READY BIT(31)
77
78 struct cdns_dphy_cfg {
79 u8 pll_ipdiv;
80 u8 pll_opdiv;
81 u16 pll_fbdiv;
82 unsigned int nlanes;
83 };
84
85 enum cdns_dphy_clk_lane_cfg {
86 DPHY_CLK_CFG_LEFT_DRIVES_ALL = 0,
87 DPHY_CLK_CFG_LEFT_DRIVES_RIGHT = 1,
88 DPHY_CLK_CFG_LEFT_DRIVES_LEFT = 2,
89 DPHY_CLK_CFG_RIGHT_DRIVES_ALL = 3,
90 };
91
92 struct cdns_dphy;
93 struct cdns_dphy_ops {
94 int (*probe)(struct cdns_dphy *dphy);
95 void (*remove)(struct cdns_dphy *dphy);
96 void (*set_psm_div)(struct cdns_dphy *dphy, u8 div);
97 void (*set_clk_lane_cfg)(struct cdns_dphy *dphy,
98 enum cdns_dphy_clk_lane_cfg cfg);
99 void (*set_pll_cfg)(struct cdns_dphy *dphy,
100 const struct cdns_dphy_cfg *cfg);
101 unsigned long (*get_wakeup_time_ns)(struct cdns_dphy *dphy);
102 };
103
104 struct cdns_dphy {
105 struct cdns_dphy_cfg cfg;
106 void __iomem *regs;
107 struct clk *psm_clk;
108 struct clk *pll_ref_clk;
109 const struct cdns_dphy_ops *ops;
110 struct phy *phy;
111 };
112
113 /* Order of bands is important since the index is the band number. */
114 static const unsigned int tx_bands[] = {
115 80, 100, 120, 160, 200, 240, 320, 390, 450, 510, 560, 640, 690, 770,
116 870, 950, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2500
117 };
118
cdns_dsi_get_dphy_pll_cfg(struct cdns_dphy * dphy,struct cdns_dphy_cfg * cfg,struct phy_configure_opts_mipi_dphy * opts,unsigned int * dsi_hfp_ext)119 static int cdns_dsi_get_dphy_pll_cfg(struct cdns_dphy *dphy,
120 struct cdns_dphy_cfg *cfg,
121 struct phy_configure_opts_mipi_dphy *opts,
122 unsigned int *dsi_hfp_ext)
123 {
124 unsigned long pll_ref_hz = clk_get_rate(dphy->pll_ref_clk);
125 u64 dlane_bps;
126
127 memset(cfg, 0, sizeof(*cfg));
128
129 if (pll_ref_hz < 9600000 || pll_ref_hz >= 150000000)
130 return -EINVAL;
131 else if (pll_ref_hz < 19200000)
132 cfg->pll_ipdiv = 1;
133 else if (pll_ref_hz < 38400000)
134 cfg->pll_ipdiv = 2;
135 else if (pll_ref_hz < 76800000)
136 cfg->pll_ipdiv = 4;
137 else
138 cfg->pll_ipdiv = 8;
139
140 dlane_bps = opts->hs_clk_rate;
141
142 if (dlane_bps > 2500000000UL || dlane_bps < 160000000UL)
143 return -EINVAL;
144 else if (dlane_bps >= 1250000000)
145 cfg->pll_opdiv = 1;
146 else if (dlane_bps >= 630000000)
147 cfg->pll_opdiv = 2;
148 else if (dlane_bps >= 320000000)
149 cfg->pll_opdiv = 4;
150 else if (dlane_bps >= 160000000)
151 cfg->pll_opdiv = 8;
152
153 cfg->pll_fbdiv = DIV_ROUND_UP_ULL(dlane_bps * 2 * cfg->pll_opdiv *
154 cfg->pll_ipdiv,
155 pll_ref_hz);
156
157 return 0;
158 }
159
cdns_dphy_setup_psm(struct cdns_dphy * dphy)160 static int cdns_dphy_setup_psm(struct cdns_dphy *dphy)
161 {
162 unsigned long psm_clk_hz = clk_get_rate(dphy->psm_clk);
163 unsigned long psm_div;
164
165 if (!psm_clk_hz || psm_clk_hz > 100000000)
166 return -EINVAL;
167
168 psm_div = DIV_ROUND_CLOSEST(psm_clk_hz, 1000000);
169 if (dphy->ops->set_psm_div)
170 dphy->ops->set_psm_div(dphy, psm_div);
171
172 return 0;
173 }
174
cdns_dphy_set_clk_lane_cfg(struct cdns_dphy * dphy,enum cdns_dphy_clk_lane_cfg cfg)175 static void cdns_dphy_set_clk_lane_cfg(struct cdns_dphy *dphy,
176 enum cdns_dphy_clk_lane_cfg cfg)
177 {
178 if (dphy->ops->set_clk_lane_cfg)
179 dphy->ops->set_clk_lane_cfg(dphy, cfg);
180 }
181
cdns_dphy_set_pll_cfg(struct cdns_dphy * dphy,const struct cdns_dphy_cfg * cfg)182 static void cdns_dphy_set_pll_cfg(struct cdns_dphy *dphy,
183 const struct cdns_dphy_cfg *cfg)
184 {
185 if (dphy->ops->set_pll_cfg)
186 dphy->ops->set_pll_cfg(dphy, cfg);
187 }
188
cdns_dphy_get_wakeup_time_ns(struct cdns_dphy * dphy)189 static unsigned long cdns_dphy_get_wakeup_time_ns(struct cdns_dphy *dphy)
190 {
191 return dphy->ops->get_wakeup_time_ns(dphy);
192 }
193
cdns_dphy_ref_get_wakeup_time_ns(struct cdns_dphy * dphy)194 static unsigned long cdns_dphy_ref_get_wakeup_time_ns(struct cdns_dphy *dphy)
195 {
196 /* Default wakeup time is 800 ns (in a simulated environment). */
197 return 800;
198 }
199
cdns_dphy_ref_set_pll_cfg(struct cdns_dphy * dphy,const struct cdns_dphy_cfg * cfg)200 static void cdns_dphy_ref_set_pll_cfg(struct cdns_dphy *dphy,
201 const struct cdns_dphy_cfg *cfg)
202 {
203 u32 fbdiv_low, fbdiv_high;
204
205 fbdiv_low = (cfg->pll_fbdiv / 4) - 2;
206 fbdiv_high = cfg->pll_fbdiv - fbdiv_low - 2;
207
208 writel(DPHY_CMN_IPDIV_FROM_REG | DPHY_CMN_OPDIV_FROM_REG |
209 DPHY_CMN_IPDIV(cfg->pll_ipdiv) |
210 DPHY_CMN_OPDIV(cfg->pll_opdiv),
211 dphy->regs + DPHY_CMN_OPIPDIV);
212 writel(DPHY_CMN_FBDIV_FROM_REG |
213 DPHY_CMN_FBDIV_VAL(fbdiv_low, fbdiv_high),
214 dphy->regs + DPHY_CMN_FBDIV);
215 writel(DPHY_CMN_PWM_HIGH(6) | DPHY_CMN_PWM_LOW(0x101) |
216 DPHY_CMN_PWM_DIV(0x8),
217 dphy->regs + DPHY_CMN_PWM);
218 }
219
cdns_dphy_ref_set_psm_div(struct cdns_dphy * dphy,u8 div)220 static void cdns_dphy_ref_set_psm_div(struct cdns_dphy *dphy, u8 div)
221 {
222 writel(DPHY_PSM_CFG_FROM_REG | DPHY_PSM_CLK_DIV(div),
223 dphy->regs + DPHY_PSM_CFG);
224 }
225
cdns_dphy_j721e_get_wakeup_time_ns(struct cdns_dphy * dphy)226 static unsigned long cdns_dphy_j721e_get_wakeup_time_ns(struct cdns_dphy *dphy)
227 {
228 /* Minimum wakeup time as per MIPI D-PHY spec v1.2 */
229 return 1000000;
230 }
231
cdns_dphy_j721e_set_pll_cfg(struct cdns_dphy * dphy,const struct cdns_dphy_cfg * cfg)232 static void cdns_dphy_j721e_set_pll_cfg(struct cdns_dphy *dphy,
233 const struct cdns_dphy_cfg *cfg)
234 {
235 u32 status;
236
237 /*
238 * set the PWM and PLL Byteclk divider settings to recommended values
239 * which is same as that of in ref ops
240 */
241 writel(DPHY_CMN_PWM_HIGH(6) | DPHY_CMN_PWM_LOW(0x101) |
242 DPHY_CMN_PWM_DIV(0x8),
243 dphy->regs + DPHY_CMN_PWM);
244
245 writel((FIELD_PREP(DPHY_TX_J721E_WIZ_IPDIV, cfg->pll_ipdiv) |
246 FIELD_PREP(DPHY_TX_J721E_WIZ_OPDIV, cfg->pll_opdiv) |
247 FIELD_PREP(DPHY_TX_J721E_WIZ_FBDIV, cfg->pll_fbdiv)),
248 dphy->regs + DPHY_TX_J721E_WIZ_PLL_CTRL);
249
250 writel(DPHY_TX_J721E_WIZ_LANE_RSTB,
251 dphy->regs + DPHY_TX_J721E_WIZ_RST_CTRL);
252
253 readl_poll_timeout(dphy->regs + DPHY_TX_J721E_WIZ_PLL_CTRL, status,
254 (status & DPHY_TX_WIZ_PLL_LOCK), 0, POLL_TIMEOUT_US);
255
256 readl_poll_timeout(dphy->regs + DPHY_TX_J721E_WIZ_STATUS, status,
257 (status & DPHY_TX_WIZ_O_CMN_READY), 0,
258 POLL_TIMEOUT_US);
259 }
260
cdns_dphy_j721e_set_psm_div(struct cdns_dphy * dphy,u8 div)261 static void cdns_dphy_j721e_set_psm_div(struct cdns_dphy *dphy, u8 div)
262 {
263 writel(div, dphy->regs + DPHY_TX_J721E_WIZ_PSM_FREQ);
264 }
265
266 /*
267 * This is the reference implementation of DPHY hooks. Specific integration of
268 * this IP may have to re-implement some of them depending on how they decided
269 * to wire things in the SoC.
270 */
271 static const struct cdns_dphy_ops ref_dphy_ops = {
272 .get_wakeup_time_ns = cdns_dphy_ref_get_wakeup_time_ns,
273 .set_pll_cfg = cdns_dphy_ref_set_pll_cfg,
274 .set_psm_div = cdns_dphy_ref_set_psm_div,
275 };
276
277 static const struct cdns_dphy_ops j721e_dphy_ops = {
278 .get_wakeup_time_ns = cdns_dphy_j721e_get_wakeup_time_ns,
279 .set_pll_cfg = cdns_dphy_j721e_set_pll_cfg,
280 .set_psm_div = cdns_dphy_j721e_set_psm_div,
281 };
282
cdns_dphy_config_from_opts(struct phy * phy,struct phy_configure_opts_mipi_dphy * opts,struct cdns_dphy_cfg * cfg)283 static int cdns_dphy_config_from_opts(struct phy *phy,
284 struct phy_configure_opts_mipi_dphy *opts,
285 struct cdns_dphy_cfg *cfg)
286 {
287 struct cdns_dphy *dphy = phy_get_drvdata(phy);
288 unsigned int dsi_hfp_ext = 0;
289 int ret;
290
291 ret = phy_mipi_dphy_config_validate(opts);
292 if (ret)
293 return ret;
294
295 ret = cdns_dsi_get_dphy_pll_cfg(dphy, cfg,
296 opts, &dsi_hfp_ext);
297 if (ret)
298 return ret;
299
300 opts->wakeup = cdns_dphy_get_wakeup_time_ns(dphy) / 1000;
301
302 return 0;
303 }
304
cdns_dphy_tx_get_band_ctrl(unsigned long hs_clk_rate)305 static int cdns_dphy_tx_get_band_ctrl(unsigned long hs_clk_rate)
306 {
307 unsigned int rate;
308 int i;
309
310 rate = hs_clk_rate / 1000000UL;
311
312 if (rate < tx_bands[0])
313 return -EOPNOTSUPP;
314
315 for (i = 0; i < ARRAY_SIZE(tx_bands) - 1; i++) {
316 if (rate >= tx_bands[i] && rate < tx_bands[i + 1])
317 return i;
318 }
319
320 return -EOPNOTSUPP;
321 }
322
cdns_dphy_validate(struct phy * phy,enum phy_mode mode,int submode,union phy_configure_opts * opts)323 static int cdns_dphy_validate(struct phy *phy, enum phy_mode mode, int submode,
324 union phy_configure_opts *opts)
325 {
326 struct cdns_dphy_cfg cfg = { 0 };
327
328 if (mode != PHY_MODE_MIPI_DPHY)
329 return -EINVAL;
330
331 return cdns_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
332 }
333
cdns_dphy_configure(struct phy * phy,union phy_configure_opts * opts)334 static int cdns_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
335 {
336 struct cdns_dphy *dphy = phy_get_drvdata(phy);
337 struct cdns_dphy_cfg cfg = { 0 };
338 int ret, band_ctrl;
339 unsigned int reg;
340
341 ret = cdns_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
342 if (ret)
343 return ret;
344
345 /*
346 * Configure the internal PSM clk divider so that the DPHY has a
347 * 1MHz clk (or something close).
348 */
349 ret = cdns_dphy_setup_psm(dphy);
350 if (ret)
351 return ret;
352
353 /*
354 * Configure attach clk lanes to data lanes: the DPHY has 2 clk lanes
355 * and 8 data lanes, each clk lane can be attache different set of
356 * data lanes. The 2 groups are named 'left' and 'right', so here we
357 * just say that we want the 'left' clk lane to drive the 'left' data
358 * lanes.
359 */
360 cdns_dphy_set_clk_lane_cfg(dphy, DPHY_CLK_CFG_LEFT_DRIVES_LEFT);
361
362 /*
363 * Configure the DPHY PLL that will be used to generate the TX byte
364 * clk.
365 */
366 cdns_dphy_set_pll_cfg(dphy, &cfg);
367
368 band_ctrl = cdns_dphy_tx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
369 if (band_ctrl < 0)
370 return band_ctrl;
371
372 reg = FIELD_PREP(DPHY_BAND_CFG_LEFT_BAND, band_ctrl) |
373 FIELD_PREP(DPHY_BAND_CFG_RIGHT_BAND, band_ctrl);
374 writel(reg, dphy->regs + DPHY_BAND_CFG);
375
376 return 0;
377 }
378
cdns_dphy_power_on(struct phy * phy)379 static int cdns_dphy_power_on(struct phy *phy)
380 {
381 struct cdns_dphy *dphy = phy_get_drvdata(phy);
382
383 clk_prepare_enable(dphy->psm_clk);
384 clk_prepare_enable(dphy->pll_ref_clk);
385
386 /* Start TX state machine. */
387 writel(DPHY_CMN_SSM_EN | DPHY_CMN_TX_MODE_EN,
388 dphy->regs + DPHY_CMN_SSM);
389
390 return 0;
391 }
392
cdns_dphy_power_off(struct phy * phy)393 static int cdns_dphy_power_off(struct phy *phy)
394 {
395 struct cdns_dphy *dphy = phy_get_drvdata(phy);
396
397 clk_disable_unprepare(dphy->pll_ref_clk);
398 clk_disable_unprepare(dphy->psm_clk);
399
400 return 0;
401 }
402
403 static const struct phy_ops cdns_dphy_ops = {
404 .configure = cdns_dphy_configure,
405 .validate = cdns_dphy_validate,
406 .power_on = cdns_dphy_power_on,
407 .power_off = cdns_dphy_power_off,
408 };
409
cdns_dphy_probe(struct platform_device * pdev)410 static int cdns_dphy_probe(struct platform_device *pdev)
411 {
412 struct phy_provider *phy_provider;
413 struct cdns_dphy *dphy;
414 int ret;
415
416 dphy = devm_kzalloc(&pdev->dev, sizeof(*dphy), GFP_KERNEL);
417 if (!dphy)
418 return -ENOMEM;
419 dev_set_drvdata(&pdev->dev, dphy);
420
421 dphy->ops = of_device_get_match_data(&pdev->dev);
422 if (!dphy->ops)
423 return -EINVAL;
424
425 dphy->regs = devm_platform_ioremap_resource(pdev, 0);
426 if (IS_ERR(dphy->regs))
427 return PTR_ERR(dphy->regs);
428
429 dphy->psm_clk = devm_clk_get(&pdev->dev, "psm");
430 if (IS_ERR(dphy->psm_clk))
431 return PTR_ERR(dphy->psm_clk);
432
433 dphy->pll_ref_clk = devm_clk_get(&pdev->dev, "pll_ref");
434 if (IS_ERR(dphy->pll_ref_clk))
435 return PTR_ERR(dphy->pll_ref_clk);
436
437 if (dphy->ops->probe) {
438 ret = dphy->ops->probe(dphy);
439 if (ret)
440 return ret;
441 }
442
443 dphy->phy = devm_phy_create(&pdev->dev, NULL, &cdns_dphy_ops);
444 if (IS_ERR(dphy->phy)) {
445 dev_err(&pdev->dev, "failed to create PHY\n");
446 if (dphy->ops->remove)
447 dphy->ops->remove(dphy);
448 return PTR_ERR(dphy->phy);
449 }
450
451 phy_set_drvdata(dphy->phy, dphy);
452 phy_provider = devm_of_phy_provider_register(&pdev->dev,
453 of_phy_simple_xlate);
454
455 return PTR_ERR_OR_ZERO(phy_provider);
456 }
457
cdns_dphy_remove(struct platform_device * pdev)458 static void cdns_dphy_remove(struct platform_device *pdev)
459 {
460 struct cdns_dphy *dphy = dev_get_drvdata(&pdev->dev);
461
462 if (dphy->ops->remove)
463 dphy->ops->remove(dphy);
464 }
465
466 static const struct of_device_id cdns_dphy_of_match[] = {
467 { .compatible = "cdns,dphy", .data = &ref_dphy_ops },
468 { .compatible = "ti,j721e-dphy", .data = &j721e_dphy_ops },
469 { /* sentinel */ },
470 };
471 MODULE_DEVICE_TABLE(of, cdns_dphy_of_match);
472
473 static struct platform_driver cdns_dphy_platform_driver = {
474 .probe = cdns_dphy_probe,
475 .remove_new = cdns_dphy_remove,
476 .driver = {
477 .name = "cdns-mipi-dphy",
478 .of_match_table = cdns_dphy_of_match,
479 },
480 };
481 module_platform_driver(cdns_dphy_platform_driver);
482
483 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@bootlin.com>");
484 MODULE_DESCRIPTION("Cadence MIPI D-PHY Driver");
485 MODULE_LICENSE("GPL");
486