1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * StarFive JH71XX PMU (Power Management Unit) Controller Driver
4  *
5  * Copyright (C) 2022-2023 StarFive Technology Co., Ltd.
6  */
7 
8 #include <linux/interrupt.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/pm_domain.h>
15 #include <dt-bindings/power/starfive,jh7110-pmu.h>
16 
17 /* register offset */
18 #define JH71XX_PMU_SW_TURN_ON_POWER	0x0C
19 #define JH71XX_PMU_SW_TURN_OFF_POWER	0x10
20 #define JH71XX_PMU_SW_ENCOURAGE		0x44
21 #define JH71XX_PMU_TIMER_INT_MASK	0x48
22 #define JH71XX_PMU_CURR_POWER_MODE	0x80
23 #define JH71XX_PMU_EVENT_STATUS		0x88
24 #define JH71XX_PMU_INT_STATUS		0x8C
25 
26 /* aon pmu register offset */
27 #define JH71XX_AON_PMU_SWITCH		0x00
28 
29 /* sw encourage cfg */
30 #define JH71XX_PMU_SW_ENCOURAGE_EN_LO	0x05
31 #define JH71XX_PMU_SW_ENCOURAGE_EN_HI	0x50
32 #define JH71XX_PMU_SW_ENCOURAGE_DIS_LO	0x0A
33 #define JH71XX_PMU_SW_ENCOURAGE_DIS_HI	0xA0
34 #define JH71XX_PMU_SW_ENCOURAGE_ON	0xFF
35 
36 /* pmu int status */
37 #define JH71XX_PMU_INT_SEQ_DONE		BIT(0)
38 #define JH71XX_PMU_INT_HW_REQ		BIT(1)
39 #define JH71XX_PMU_INT_SW_FAIL		GENMASK(3, 2)
40 #define JH71XX_PMU_INT_HW_FAIL		GENMASK(5, 4)
41 #define JH71XX_PMU_INT_PCH_FAIL		GENMASK(8, 6)
42 #define JH71XX_PMU_INT_ALL_MASK		GENMASK(8, 0)
43 
44 /*
45  * The time required for switching power status is based on the time
46  * to turn on the largest domain's power, which is at microsecond level
47  */
48 #define JH71XX_PMU_TIMEOUT_US		100
49 
50 struct jh71xx_domain_info {
51 	const char * const name;
52 	unsigned int flags;
53 	u8 bit;
54 };
55 
56 struct jh71xx_pmu;
57 struct jh71xx_pmu_dev;
58 
59 struct jh71xx_pmu_match_data {
60 	const struct jh71xx_domain_info *domain_info;
61 	int num_domains;
62 	unsigned int pmu_status;
63 	int (*pmu_parse_irq)(struct platform_device *pdev,
64 			     struct jh71xx_pmu *pmu);
65 	int (*pmu_set_state)(struct jh71xx_pmu_dev *pmd,
66 			     u32 mask, bool on);
67 };
68 
69 struct jh71xx_pmu {
70 	struct device *dev;
71 	const struct jh71xx_pmu_match_data *match_data;
72 	void __iomem *base;
73 	struct generic_pm_domain **genpd;
74 	struct genpd_onecell_data genpd_data;
75 	int irq;
76 	spinlock_t lock;	/* protects pmu reg */
77 };
78 
79 struct jh71xx_pmu_dev {
80 	const struct jh71xx_domain_info *domain_info;
81 	struct jh71xx_pmu *pmu;
82 	struct generic_pm_domain genpd;
83 };
84 
85 static int jh71xx_pmu_get_state(struct jh71xx_pmu_dev *pmd, u32 mask, bool *is_on)
86 {
87 	struct jh71xx_pmu *pmu = pmd->pmu;
88 
89 	if (!mask)
90 		return -EINVAL;
91 
92 	*is_on = readl(pmu->base + pmu->match_data->pmu_status) & mask;
93 
94 	return 0;
95 }
96 
97 static int jh7110_pmu_set_state(struct jh71xx_pmu_dev *pmd, u32 mask, bool on)
98 {
99 	struct jh71xx_pmu *pmu = pmd->pmu;
100 	unsigned long flags;
101 	u32 val;
102 	u32 mode;
103 	u32 encourage_lo;
104 	u32 encourage_hi;
105 	int ret;
106 
107 	spin_lock_irqsave(&pmu->lock, flags);
108 
109 	/*
110 	 * The PMU accepts software encourage to switch power mode in the following 2 steps:
111 	 *
112 	 * 1.Configure the register SW_TURN_ON_POWER (offset 0x0c) by writing 1 to
113 	 *   the bit corresponding to the power domain that will be turned on
114 	 *   and writing 0 to the others.
115 	 *   Likewise, configure the register SW_TURN_OFF_POWER (offset 0x10) by
116 	 *   writing 1 to the bit corresponding to the power domain that will be
117 	 *   turned off and writing 0 to the others.
118 	 */
119 	if (on) {
120 		mode = JH71XX_PMU_SW_TURN_ON_POWER;
121 		encourage_lo = JH71XX_PMU_SW_ENCOURAGE_EN_LO;
122 		encourage_hi = JH71XX_PMU_SW_ENCOURAGE_EN_HI;
123 	} else {
124 		mode = JH71XX_PMU_SW_TURN_OFF_POWER;
125 		encourage_lo = JH71XX_PMU_SW_ENCOURAGE_DIS_LO;
126 		encourage_hi = JH71XX_PMU_SW_ENCOURAGE_DIS_HI;
127 	}
128 
129 	writel(mask, pmu->base + mode);
130 
131 	/*
132 	 * 2.Write SW encourage command sequence to the Software Encourage Reg (offset 0x44)
133 	 *   First write SW_MODE_ENCOURAGE_ON to JH71XX_PMU_SW_ENCOURAGE. This will reset
134 	 *   the state machine which parses the command sequence. This register must be
135 	 *   written every time software wants to power on/off a domain.
136 	 *   Then write the lower bits of the command sequence, followed by the upper
137 	 *   bits. The sequence differs between powering on & off a domain.
138 	 */
139 	writel(JH71XX_PMU_SW_ENCOURAGE_ON, pmu->base + JH71XX_PMU_SW_ENCOURAGE);
140 	writel(encourage_lo, pmu->base + JH71XX_PMU_SW_ENCOURAGE);
141 	writel(encourage_hi, pmu->base + JH71XX_PMU_SW_ENCOURAGE);
142 
143 	spin_unlock_irqrestore(&pmu->lock, flags);
144 
145 	/* Wait for the power domain bit to be enabled / disabled */
146 	if (on) {
147 		ret = readl_poll_timeout_atomic(pmu->base + JH71XX_PMU_CURR_POWER_MODE,
148 						val, val & mask,
149 						1, JH71XX_PMU_TIMEOUT_US);
150 	} else {
151 		ret = readl_poll_timeout_atomic(pmu->base + JH71XX_PMU_CURR_POWER_MODE,
152 						val, !(val & mask),
153 						1, JH71XX_PMU_TIMEOUT_US);
154 	}
155 
156 	if (ret) {
157 		dev_err(pmu->dev, "%s: failed to power %s\n",
158 			pmd->genpd.name, on ? "on" : "off");
159 		return -ETIMEDOUT;
160 	}
161 
162 	return 0;
163 }
164 
165 static int jh7110_aon_pmu_set_state(struct jh71xx_pmu_dev *pmd, u32 mask, bool on)
166 {
167 	struct jh71xx_pmu *pmu = pmd->pmu;
168 	unsigned long flags;
169 	u32 val;
170 
171 	spin_lock_irqsave(&pmu->lock, flags);
172 	val = readl(pmu->base + JH71XX_AON_PMU_SWITCH);
173 
174 	if (on)
175 		val |= mask;
176 	else
177 		val &= ~mask;
178 
179 	writel(val, pmu->base + JH71XX_AON_PMU_SWITCH);
180 	spin_unlock_irqrestore(&pmu->lock, flags);
181 
182 	return 0;
183 }
184 
185 static int jh71xx_pmu_set_state(struct jh71xx_pmu_dev *pmd, u32 mask, bool on)
186 {
187 	struct jh71xx_pmu *pmu = pmd->pmu;
188 	const struct jh71xx_pmu_match_data *match_data = pmu->match_data;
189 	bool is_on;
190 	int ret;
191 
192 	ret = jh71xx_pmu_get_state(pmd, mask, &is_on);
193 	if (ret) {
194 		dev_dbg(pmu->dev, "unable to get current state for %s\n",
195 			pmd->genpd.name);
196 		return ret;
197 	}
198 
199 	if (is_on == on) {
200 		dev_dbg(pmu->dev, "pm domain [%s] is already %sable status.\n",
201 			pmd->genpd.name, on ? "en" : "dis");
202 		return 0;
203 	}
204 
205 	return match_data->pmu_set_state(pmd, mask, on);
206 }
207 
208 static int jh71xx_pmu_on(struct generic_pm_domain *genpd)
209 {
210 	struct jh71xx_pmu_dev *pmd = container_of(genpd,
211 						  struct jh71xx_pmu_dev, genpd);
212 	u32 pwr_mask = BIT(pmd->domain_info->bit);
213 
214 	return jh71xx_pmu_set_state(pmd, pwr_mask, true);
215 }
216 
217 static int jh71xx_pmu_off(struct generic_pm_domain *genpd)
218 {
219 	struct jh71xx_pmu_dev *pmd = container_of(genpd,
220 						  struct jh71xx_pmu_dev, genpd);
221 	u32 pwr_mask = BIT(pmd->domain_info->bit);
222 
223 	return jh71xx_pmu_set_state(pmd, pwr_mask, false);
224 }
225 
226 static void jh71xx_pmu_int_enable(struct jh71xx_pmu *pmu, u32 mask, bool enable)
227 {
228 	u32 val;
229 	unsigned long flags;
230 
231 	spin_lock_irqsave(&pmu->lock, flags);
232 	val = readl(pmu->base + JH71XX_PMU_TIMER_INT_MASK);
233 
234 	if (enable)
235 		val &= ~mask;
236 	else
237 		val |= mask;
238 
239 	writel(val, pmu->base + JH71XX_PMU_TIMER_INT_MASK);
240 	spin_unlock_irqrestore(&pmu->lock, flags);
241 }
242 
243 static irqreturn_t jh71xx_pmu_interrupt(int irq, void *data)
244 {
245 	struct jh71xx_pmu *pmu = data;
246 	u32 val;
247 
248 	val = readl(pmu->base + JH71XX_PMU_INT_STATUS);
249 
250 	if (val & JH71XX_PMU_INT_SEQ_DONE)
251 		dev_dbg(pmu->dev, "sequence done.\n");
252 	if (val & JH71XX_PMU_INT_HW_REQ)
253 		dev_dbg(pmu->dev, "hardware encourage requestion.\n");
254 	if (val & JH71XX_PMU_INT_SW_FAIL)
255 		dev_err(pmu->dev, "software encourage fail.\n");
256 	if (val & JH71XX_PMU_INT_HW_FAIL)
257 		dev_err(pmu->dev, "hardware encourage fail.\n");
258 	if (val & JH71XX_PMU_INT_PCH_FAIL)
259 		dev_err(pmu->dev, "p-channel fail event.\n");
260 
261 	/* clear interrupts */
262 	writel(val, pmu->base + JH71XX_PMU_INT_STATUS);
263 	writel(val, pmu->base + JH71XX_PMU_EVENT_STATUS);
264 
265 	return IRQ_HANDLED;
266 }
267 
268 static int jh7110_pmu_parse_irq(struct platform_device *pdev, struct jh71xx_pmu *pmu)
269 {
270 	struct device *dev = &pdev->dev;
271 	int ret;
272 
273 	pmu->irq = platform_get_irq(pdev, 0);
274 	if (pmu->irq < 0)
275 		return pmu->irq;
276 
277 	ret = devm_request_irq(dev, pmu->irq, jh71xx_pmu_interrupt,
278 			       0, pdev->name, pmu);
279 	if (ret)
280 		dev_err(dev, "failed to request irq\n");
281 
282 	jh71xx_pmu_int_enable(pmu, JH71XX_PMU_INT_ALL_MASK & ~JH71XX_PMU_INT_PCH_FAIL, true);
283 
284 	return 0;
285 }
286 
287 static int jh71xx_pmu_init_domain(struct jh71xx_pmu *pmu, int index)
288 {
289 	struct jh71xx_pmu_dev *pmd;
290 	u32 pwr_mask;
291 	int ret;
292 	bool is_on = false;
293 
294 	pmd = devm_kzalloc(pmu->dev, sizeof(*pmd), GFP_KERNEL);
295 	if (!pmd)
296 		return -ENOMEM;
297 
298 	pmd->domain_info = &pmu->match_data->domain_info[index];
299 	pmd->pmu = pmu;
300 	pwr_mask = BIT(pmd->domain_info->bit);
301 
302 	pmd->genpd.name = pmd->domain_info->name;
303 	pmd->genpd.flags = pmd->domain_info->flags;
304 
305 	ret = jh71xx_pmu_get_state(pmd, pwr_mask, &is_on);
306 	if (ret)
307 		dev_warn(pmu->dev, "unable to get current state for %s\n",
308 			 pmd->genpd.name);
309 
310 	pmd->genpd.power_on = jh71xx_pmu_on;
311 	pmd->genpd.power_off = jh71xx_pmu_off;
312 	pm_genpd_init(&pmd->genpd, NULL, !is_on);
313 
314 	pmu->genpd_data.domains[index] = &pmd->genpd;
315 
316 	return 0;
317 }
318 
319 static int jh71xx_pmu_probe(struct platform_device *pdev)
320 {
321 	struct device *dev = &pdev->dev;
322 	struct device_node *np = dev->of_node;
323 	const struct jh71xx_pmu_match_data *match_data;
324 	struct jh71xx_pmu *pmu;
325 	unsigned int i;
326 	int ret;
327 
328 	pmu = devm_kzalloc(dev, sizeof(*pmu), GFP_KERNEL);
329 	if (!pmu)
330 		return -ENOMEM;
331 
332 	pmu->base = devm_platform_ioremap_resource(pdev, 0);
333 	if (IS_ERR(pmu->base))
334 		return PTR_ERR(pmu->base);
335 
336 	spin_lock_init(&pmu->lock);
337 
338 	match_data = of_device_get_match_data(dev);
339 	if (!match_data)
340 		return -EINVAL;
341 
342 	if (match_data->pmu_parse_irq) {
343 		ret = match_data->pmu_parse_irq(pdev, pmu);
344 		if (ret) {
345 			dev_err(dev, "failed to parse irq\n");
346 			return ret;
347 		}
348 	}
349 
350 	pmu->genpd = devm_kcalloc(dev, match_data->num_domains,
351 				  sizeof(struct generic_pm_domain *),
352 				  GFP_KERNEL);
353 	if (!pmu->genpd)
354 		return -ENOMEM;
355 
356 	pmu->dev = dev;
357 	pmu->match_data = match_data;
358 	pmu->genpd_data.domains = pmu->genpd;
359 	pmu->genpd_data.num_domains = match_data->num_domains;
360 
361 	for (i = 0; i < match_data->num_domains; i++) {
362 		ret = jh71xx_pmu_init_domain(pmu, i);
363 		if (ret) {
364 			dev_err(dev, "failed to initialize power domain\n");
365 			return ret;
366 		}
367 	}
368 
369 	ret = of_genpd_add_provider_onecell(np, &pmu->genpd_data);
370 	if (ret) {
371 		dev_err(dev, "failed to register genpd driver: %d\n", ret);
372 		return ret;
373 	}
374 
375 	dev_dbg(dev, "registered %u power domains\n", i);
376 
377 	return 0;
378 }
379 
380 static const struct jh71xx_domain_info jh7110_power_domains[] = {
381 	[JH7110_PD_SYSTOP] = {
382 		.name = "SYSTOP",
383 		.bit = 0,
384 		.flags = GENPD_FLAG_ALWAYS_ON,
385 	},
386 	[JH7110_PD_CPU] = {
387 		.name = "CPU",
388 		.bit = 1,
389 		.flags = GENPD_FLAG_ALWAYS_ON,
390 	},
391 	[JH7110_PD_GPUA] = {
392 		.name = "GPUA",
393 		.bit = 2,
394 	},
395 	[JH7110_PD_VDEC] = {
396 		.name = "VDEC",
397 		.bit = 3,
398 	},
399 	[JH7110_PD_VOUT] = {
400 		.name = "VOUT",
401 		.bit = 4,
402 	},
403 	[JH7110_PD_ISP] = {
404 		.name = "ISP",
405 		.bit = 5,
406 	},
407 	[JH7110_PD_VENC] = {
408 		.name = "VENC",
409 		.bit = 6,
410 	},
411 };
412 
413 static const struct jh71xx_pmu_match_data jh7110_pmu = {
414 	.num_domains = ARRAY_SIZE(jh7110_power_domains),
415 	.domain_info = jh7110_power_domains,
416 	.pmu_status = JH71XX_PMU_CURR_POWER_MODE,
417 	.pmu_parse_irq = jh7110_pmu_parse_irq,
418 	.pmu_set_state = jh7110_pmu_set_state,
419 };
420 
421 static const struct jh71xx_domain_info jh7110_aon_power_domains[] = {
422 	[JH7110_AON_PD_DPHY_TX] = {
423 		.name = "DPHY-TX",
424 		.bit = 30,
425 	},
426 	[JH7110_AON_PD_DPHY_RX] = {
427 		.name = "DPHY-RX",
428 		.bit = 31,
429 	},
430 };
431 
432 static const struct jh71xx_pmu_match_data jh7110_aon_pmu = {
433 	.num_domains = ARRAY_SIZE(jh7110_aon_power_domains),
434 	.domain_info = jh7110_aon_power_domains,
435 	.pmu_status = JH71XX_AON_PMU_SWITCH,
436 	.pmu_set_state = jh7110_aon_pmu_set_state,
437 };
438 
439 static const struct of_device_id jh71xx_pmu_of_match[] = {
440 	{
441 		.compatible = "starfive,jh7110-pmu",
442 		.data = (void *)&jh7110_pmu,
443 	}, {
444 		.compatible = "starfive,jh7110-aon-syscon",
445 		.data = (void *)&jh7110_aon_pmu,
446 	}, {
447 		/* sentinel */
448 	}
449 };
450 
451 static struct platform_driver jh71xx_pmu_driver = {
452 	.probe = jh71xx_pmu_probe,
453 	.driver = {
454 		.name = "jh71xx-pmu",
455 		.of_match_table = jh71xx_pmu_of_match,
456 		.suppress_bind_attrs = true,
457 	},
458 };
459 builtin_platform_driver(jh71xx_pmu_driver);
460 
461 MODULE_AUTHOR("Walker Chen <walker.chen@starfivetech.com>");
462 MODULE_AUTHOR("Changhuang Liang <changhuang.liang@starfivetech.com>");
463 MODULE_DESCRIPTION("StarFive JH71XX PMU Driver");
464 MODULE_LICENSE("GPL");
465