1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 Freescale Semiconductor, Inc.
4  * Copyright 2017-2018 NXP
5  *	Dong Aisheng <aisheng.dong@nxp.com>
6  *
7  * Implementation of the SCU based Power Domains
8  *
9  * NOTE: a better implementation suggested by Ulf Hansson is using a
10  * single global power domain and implement the ->attach|detach_dev()
11  * callback for the genpd and use the regular of_genpd_add_provider_simple().
12  * From within the ->attach_dev(), we could get the OF node for
13  * the device that is being attached and then parse the power-domain
14  * cell containing the "resource id" and store that in the per device
15  * struct generic_pm_domain_data (we have void pointer there for
16  * storing these kind of things).
17  *
18  * Additionally, we need to implement the ->stop() and ->start()
19  * callbacks of genpd, which is where you "power on/off" devices,
20  * rather than using the above ->power_on|off() callbacks.
21  *
22  * However, there're two known issues:
23  * 1. The ->attach_dev() of power domain infrastructure still does
24  *    not support multi domains case as the struct device *dev passed
25  *    in is a virtual PD device, it does not help for parsing the real
26  *    device resource id from device tree, so it's unware of which
27  *    real sub power domain of device should be attached.
28  *
29  *    The framework needs some proper extension to support multi power
30  *    domain cases.
31  *
32  *    Update: Genpd assigns the ->of_node for the virtual device before it
33  *    invokes ->attach_dev() callback, hence parsing for device resources via
34  *    DT should work fine.
35  *
36  * 2. It also breaks most of current drivers as the driver probe sequence
37  *    behavior changed if removing ->power_on|off() callback and use
38  *    ->start() and ->stop() instead. genpd_dev_pm_attach will only power
39  *    up the domain and attach device, but will not call .start() which
40  *    relies on device runtime pm. That means the device power is still
41  *    not up before running driver probe function. For SCU enabled
42  *    platforms, all device drivers accessing registers/clock without power
43  *    domain enabled will trigger a HW access error. That means we need fix
44  *    most drivers probe sequence with proper runtime pm.
45  *
46  *    Update: Runtime PM support isn't necessary. Instead, this can easily be
47  *    fixed in drivers by adding a call to dev_pm_domain_start() during probe.
48  *
49  * In summary, the second part needs to be addressed via minor updates to the
50  * relevant drivers, before the "single global power domain" model can be used.
51  *
52  */
53 
54 #include <dt-bindings/firmware/imx/rsrc.h>
55 #include <linux/firmware/imx/sci.h>
56 #include <linux/firmware/imx/svc/rm.h>
57 #include <linux/io.h>
58 #include <linux/module.h>
59 #include <linux/of.h>
60 #include <linux/of_address.h>
61 #include <linux/of_platform.h>
62 #include <linux/platform_device.h>
63 #include <linux/pm.h>
64 #include <linux/pm_domain.h>
65 #include <linux/slab.h>
66 
67 /* SCU Power Mode Protocol definition */
68 struct imx_sc_msg_req_set_resource_power_mode {
69 	struct imx_sc_rpc_msg hdr;
70 	u16 resource;
71 	u8 mode;
72 } __packed __aligned(4);
73 
74 #define IMX_SCU_PD_NAME_SIZE 20
75 struct imx_sc_pm_domain {
76 	struct generic_pm_domain pd;
77 	char name[IMX_SCU_PD_NAME_SIZE];
78 	u32 rsrc;
79 };
80 
81 struct imx_sc_pd_range {
82 	char *name;
83 	u32 rsrc;
84 	u8 num;
85 
86 	/* add domain index */
87 	bool postfix;
88 	u8 start_from;
89 };
90 
91 struct imx_sc_pd_soc {
92 	const struct imx_sc_pd_range *pd_ranges;
93 	u8 num_ranges;
94 };
95 
96 static int imx_con_rsrc;
97 
98 static const struct imx_sc_pd_range imx8qxp_scu_pd_ranges[] = {
99 	/* LSIO SS */
100 	{ "pwm", IMX_SC_R_PWM_0, 8, true, 0 },
101 	{ "gpio", IMX_SC_R_GPIO_0, 8, true, 0 },
102 	{ "gpt", IMX_SC_R_GPT_0, 5, true, 0 },
103 	{ "kpp", IMX_SC_R_KPP, 1, false, 0 },
104 	{ "fspi", IMX_SC_R_FSPI_0, 2, true, 0 },
105 	{ "mu_a", IMX_SC_R_MU_0A, 14, true, 0 },
106 	{ "mu_b", IMX_SC_R_MU_5B, 9, true, 5 },
107 
108 	/* CONN SS */
109 	{ "usb", IMX_SC_R_USB_0, 2, true, 0 },
110 	{ "usb0phy", IMX_SC_R_USB_0_PHY, 1, false, 0 },
111 	{ "usb1phy", IMX_SC_R_USB_1_PHY, 1, false, 0},
112 	{ "usb2", IMX_SC_R_USB_2, 1, false, 0 },
113 	{ "usb2phy", IMX_SC_R_USB_2_PHY, 1, false, 0 },
114 	{ "sdhc", IMX_SC_R_SDHC_0, 3, true, 0 },
115 	{ "enet", IMX_SC_R_ENET_0, 2, true, 0 },
116 	{ "nand", IMX_SC_R_NAND, 1, false, 0 },
117 	{ "mlb", IMX_SC_R_MLB_0, 1, true, 0 },
118 
119 	/* AUDIO SS */
120 	{ "audio-pll0", IMX_SC_R_AUDIO_PLL_0, 1, false, 0 },
121 	{ "audio-pll1", IMX_SC_R_AUDIO_PLL_1, 1, false, 0 },
122 	{ "audio-clk-0", IMX_SC_R_AUDIO_CLK_0, 1, false, 0 },
123 	{ "audio-clk-1", IMX_SC_R_AUDIO_CLK_1, 1, false, 0 },
124 	{ "dma0-ch", IMX_SC_R_DMA_0_CH0, 16, true, 0 },
125 	{ "dma1-ch", IMX_SC_R_DMA_1_CH0, 16, true, 0 },
126 	{ "dma2-ch", IMX_SC_R_DMA_2_CH0, 5, true, 0 },
127 	{ "asrc0", IMX_SC_R_ASRC_0, 1, false, 0 },
128 	{ "asrc1", IMX_SC_R_ASRC_1, 1, false, 0 },
129 	{ "esai0", IMX_SC_R_ESAI_0, 1, false, 0 },
130 	{ "spdif0", IMX_SC_R_SPDIF_0, 1, false, 0 },
131 	{ "spdif1", IMX_SC_R_SPDIF_1, 1, false, 0 },
132 	{ "sai", IMX_SC_R_SAI_0, 3, true, 0 },
133 	{ "sai3", IMX_SC_R_SAI_3, 1, false, 0 },
134 	{ "sai4", IMX_SC_R_SAI_4, 1, false, 0 },
135 	{ "sai5", IMX_SC_R_SAI_5, 1, false, 0 },
136 	{ "sai6", IMX_SC_R_SAI_6, 1, false, 0 },
137 	{ "sai7", IMX_SC_R_SAI_7, 1, false, 0 },
138 	{ "amix", IMX_SC_R_AMIX, 1, false, 0 },
139 	{ "mqs0", IMX_SC_R_MQS_0, 1, false, 0 },
140 	{ "dsp", IMX_SC_R_DSP, 1, false, 0 },
141 	{ "dsp-ram", IMX_SC_R_DSP_RAM, 1, false, 0 },
142 
143 	/* DMA SS */
144 	{ "can", IMX_SC_R_CAN_0, 3, true, 0 },
145 	{ "ftm", IMX_SC_R_FTM_0, 2, true, 0 },
146 	{ "lpi2c", IMX_SC_R_I2C_0, 4, true, 0 },
147 	{ "adc", IMX_SC_R_ADC_0, 2, true, 0 },
148 	{ "lcd", IMX_SC_R_LCD_0, 1, true, 0 },
149 	{ "lcd0-pwm", IMX_SC_R_LCD_0_PWM_0, 1, true, 0 },
150 	{ "lpuart", IMX_SC_R_UART_0, 4, true, 0 },
151 	{ "lpspi", IMX_SC_R_SPI_0, 4, true, 0 },
152 	{ "irqstr_dsp", IMX_SC_R_IRQSTR_DSP, 1, false, 0 },
153 
154 	/* VPU SS */
155 	{ "vpu", IMX_SC_R_VPU, 1, false, 0 },
156 	{ "vpu-pid", IMX_SC_R_VPU_PID0, 8, true, 0 },
157 	{ "vpu-dec0", IMX_SC_R_VPU_DEC_0, 1, false, 0 },
158 	{ "vpu-enc0", IMX_SC_R_VPU_ENC_0, 1, false, 0 },
159 	{ "vpu-enc1", IMX_SC_R_VPU_ENC_1, 1, false, 0 },
160 	{ "vpu-mu0", IMX_SC_R_VPU_MU_0, 1, false, 0 },
161 	{ "vpu-mu1", IMX_SC_R_VPU_MU_1, 1, false, 0 },
162 	{ "vpu-mu2", IMX_SC_R_VPU_MU_2, 1, false, 0 },
163 
164 	/* GPU SS */
165 	{ "gpu0-pid", IMX_SC_R_GPU_0_PID0, 4, true, 0 },
166 
167 	/* HSIO SS */
168 	{ "pcie-b", IMX_SC_R_PCIE_B, 1, false, 0 },
169 	{ "serdes-1", IMX_SC_R_SERDES_1, 1, false, 0 },
170 	{ "hsio-gpio", IMX_SC_R_HSIO_GPIO, 1, false, 0 },
171 
172 	/* MIPI SS */
173 	{ "mipi0", IMX_SC_R_MIPI_0, 1, false, 0 },
174 	{ "mipi0-pwm0", IMX_SC_R_MIPI_0_PWM_0, 1, false, 0 },
175 	{ "mipi0-i2c", IMX_SC_R_MIPI_0_I2C_0, 2, true, 0 },
176 
177 	{ "mipi1", IMX_SC_R_MIPI_1, 1, false, 0 },
178 	{ "mipi1-pwm0", IMX_SC_R_MIPI_1_PWM_0, 1, false, 0 },
179 	{ "mipi1-i2c", IMX_SC_R_MIPI_1_I2C_0, 2, true, 0 },
180 
181 	/* LVDS SS */
182 	{ "lvds0", IMX_SC_R_LVDS_0, 1, false, 0 },
183 	{ "lvds1", IMX_SC_R_LVDS_1, 1, false, 0 },
184 
185 	/* DC SS */
186 	{ "dc0", IMX_SC_R_DC_0, 1, false, 0 },
187 	{ "dc0-pll", IMX_SC_R_DC_0_PLL_0, 2, true, 0 },
188 	{ "dc0-video", IMX_SC_R_DC_0_VIDEO0, 2, true, 0 },
189 
190 	/* CM40 SS */
191 	{ "cm40-i2c", IMX_SC_R_M4_0_I2C, 1, false, 0 },
192 	{ "cm40-intmux", IMX_SC_R_M4_0_INTMUX, 1, false, 0 },
193 	{ "cm40-pid", IMX_SC_R_M4_0_PID0, 5, true, 0},
194 	{ "cm40-mu-a1", IMX_SC_R_M4_0_MU_1A, 1, false, 0},
195 	{ "cm40-lpuart", IMX_SC_R_M4_0_UART, 1, false, 0},
196 
197 	/* CM41 SS */
198 	{ "cm41-i2c", IMX_SC_R_M4_1_I2C, 1, false, 0 },
199 	{ "cm41-intmux", IMX_SC_R_M4_1_INTMUX, 1, false, 0 },
200 	{ "cm41-pid", IMX_SC_R_M4_1_PID0, 5, true, 0},
201 	{ "cm41-mu-a1", IMX_SC_R_M4_1_MU_1A, 1, false, 0},
202 	{ "cm41-lpuart", IMX_SC_R_M4_1_UART, 1, false, 0},
203 
204 	/* IMAGE SS */
205 	{ "img-jpegdec-mp", IMX_SC_R_MJPEG_DEC_MP, 1, false, 0 },
206 	{ "img-jpegdec-s0", IMX_SC_R_MJPEG_DEC_S0, 4, true, 0 },
207 	{ "img-jpegenc-mp", IMX_SC_R_MJPEG_ENC_MP, 1, false, 0 },
208 	{ "img-jpegenc-s0", IMX_SC_R_MJPEG_ENC_S0, 4, true, 0 },
209 };
210 
211 static const struct imx_sc_pd_soc imx8qxp_scu_pd = {
212 	.pd_ranges = imx8qxp_scu_pd_ranges,
213 	.num_ranges = ARRAY_SIZE(imx8qxp_scu_pd_ranges),
214 };
215 
216 static struct imx_sc_ipc *pm_ipc_handle;
217 
218 static inline struct imx_sc_pm_domain *
to_imx_sc_pd(struct generic_pm_domain * genpd)219 to_imx_sc_pd(struct generic_pm_domain *genpd)
220 {
221 	return container_of(genpd, struct imx_sc_pm_domain, pd);
222 }
223 
imx_sc_pd_get_console_rsrc(void)224 static void imx_sc_pd_get_console_rsrc(void)
225 {
226 	struct of_phandle_args specs;
227 	int ret;
228 
229 	if (!of_stdout)
230 		return;
231 
232 	ret = of_parse_phandle_with_args(of_stdout, "power-domains",
233 					 "#power-domain-cells",
234 					 0, &specs);
235 	if (ret)
236 		return;
237 
238 	imx_con_rsrc = specs.args[0];
239 }
240 
imx_sc_pd_power(struct generic_pm_domain * domain,bool power_on)241 static int imx_sc_pd_power(struct generic_pm_domain *domain, bool power_on)
242 {
243 	struct imx_sc_msg_req_set_resource_power_mode msg;
244 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
245 	struct imx_sc_pm_domain *pd;
246 	int ret;
247 
248 	pd = to_imx_sc_pd(domain);
249 
250 	hdr->ver = IMX_SC_RPC_VERSION;
251 	hdr->svc = IMX_SC_RPC_SVC_PM;
252 	hdr->func = IMX_SC_PM_FUNC_SET_RESOURCE_POWER_MODE;
253 	hdr->size = 2;
254 
255 	msg.resource = pd->rsrc;
256 	msg.mode = power_on ? IMX_SC_PM_PW_MODE_ON : IMX_SC_PM_PW_MODE_LP;
257 
258 	ret = imx_scu_call_rpc(pm_ipc_handle, &msg, true);
259 	if (ret)
260 		dev_err(&domain->dev, "failed to power %s resource %d ret %d\n",
261 			power_on ? "up" : "off", pd->rsrc, ret);
262 
263 	return ret;
264 }
265 
imx_sc_pd_power_on(struct generic_pm_domain * domain)266 static int imx_sc_pd_power_on(struct generic_pm_domain *domain)
267 {
268 	return imx_sc_pd_power(domain, true);
269 }
270 
imx_sc_pd_power_off(struct generic_pm_domain * domain)271 static int imx_sc_pd_power_off(struct generic_pm_domain *domain)
272 {
273 	return imx_sc_pd_power(domain, false);
274 }
275 
imx_scu_pd_xlate(struct of_phandle_args * spec,void * data)276 static struct generic_pm_domain *imx_scu_pd_xlate(struct of_phandle_args *spec,
277 						  void *data)
278 {
279 	struct generic_pm_domain *domain = ERR_PTR(-ENOENT);
280 	struct genpd_onecell_data *pd_data = data;
281 	unsigned int i;
282 
283 	for (i = 0; i < pd_data->num_domains; i++) {
284 		struct imx_sc_pm_domain *sc_pd;
285 
286 		sc_pd = to_imx_sc_pd(pd_data->domains[i]);
287 		if (sc_pd->rsrc == spec->args[0]) {
288 			domain = &sc_pd->pd;
289 			break;
290 		}
291 	}
292 
293 	return domain;
294 }
295 
296 static struct imx_sc_pm_domain *
imx_scu_add_pm_domain(struct device * dev,int idx,const struct imx_sc_pd_range * pd_ranges)297 imx_scu_add_pm_domain(struct device *dev, int idx,
298 		      const struct imx_sc_pd_range *pd_ranges)
299 {
300 	struct imx_sc_pm_domain *sc_pd;
301 	bool is_off = true;
302 	int ret;
303 
304 	if (!imx_sc_rm_is_resource_owned(pm_ipc_handle, pd_ranges->rsrc + idx))
305 		return NULL;
306 
307 	sc_pd = devm_kzalloc(dev, sizeof(*sc_pd), GFP_KERNEL);
308 	if (!sc_pd)
309 		return ERR_PTR(-ENOMEM);
310 
311 	sc_pd->rsrc = pd_ranges->rsrc + idx;
312 	sc_pd->pd.power_off = imx_sc_pd_power_off;
313 	sc_pd->pd.power_on = imx_sc_pd_power_on;
314 
315 	if (pd_ranges->postfix)
316 		snprintf(sc_pd->name, sizeof(sc_pd->name),
317 			 "%s%i", pd_ranges->name, pd_ranges->start_from + idx);
318 	else
319 		snprintf(sc_pd->name, sizeof(sc_pd->name),
320 			 "%s", pd_ranges->name);
321 
322 	sc_pd->pd.name = sc_pd->name;
323 	if (imx_con_rsrc == sc_pd->rsrc) {
324 		sc_pd->pd.flags = GENPD_FLAG_RPM_ALWAYS_ON;
325 		is_off = false;
326 	}
327 
328 	if (sc_pd->rsrc >= IMX_SC_R_LAST) {
329 		dev_warn(dev, "invalid pd %s rsrc id %d found",
330 			 sc_pd->name, sc_pd->rsrc);
331 
332 		devm_kfree(dev, sc_pd);
333 		return NULL;
334 	}
335 
336 	ret = pm_genpd_init(&sc_pd->pd, NULL, is_off);
337 	if (ret) {
338 		dev_warn(dev, "failed to init pd %s rsrc id %d",
339 			 sc_pd->name, sc_pd->rsrc);
340 		devm_kfree(dev, sc_pd);
341 		return NULL;
342 	}
343 
344 	return sc_pd;
345 }
346 
imx_scu_init_pm_domains(struct device * dev,const struct imx_sc_pd_soc * pd_soc)347 static int imx_scu_init_pm_domains(struct device *dev,
348 				    const struct imx_sc_pd_soc *pd_soc)
349 {
350 	const struct imx_sc_pd_range *pd_ranges = pd_soc->pd_ranges;
351 	struct generic_pm_domain **domains;
352 	struct genpd_onecell_data *pd_data;
353 	struct imx_sc_pm_domain *sc_pd;
354 	u32 count = 0;
355 	int i, j;
356 
357 	for (i = 0; i < pd_soc->num_ranges; i++)
358 		count += pd_ranges[i].num;
359 
360 	domains = devm_kcalloc(dev, count, sizeof(*domains), GFP_KERNEL);
361 	if (!domains)
362 		return -ENOMEM;
363 
364 	pd_data = devm_kzalloc(dev, sizeof(*pd_data), GFP_KERNEL);
365 	if (!pd_data)
366 		return -ENOMEM;
367 
368 	count = 0;
369 	for (i = 0; i < pd_soc->num_ranges; i++) {
370 		for (j = 0; j < pd_ranges[i].num; j++) {
371 			sc_pd = imx_scu_add_pm_domain(dev, j, &pd_ranges[i]);
372 			if (IS_ERR_OR_NULL(sc_pd))
373 				continue;
374 
375 			domains[count++] = &sc_pd->pd;
376 			dev_dbg(dev, "added power domain %s\n", sc_pd->pd.name);
377 		}
378 	}
379 
380 	pd_data->domains = domains;
381 	pd_data->num_domains = count;
382 	pd_data->xlate = imx_scu_pd_xlate;
383 
384 	of_genpd_add_provider_onecell(dev->of_node, pd_data);
385 
386 	return 0;
387 }
388 
imx_sc_pd_probe(struct platform_device * pdev)389 static int imx_sc_pd_probe(struct platform_device *pdev)
390 {
391 	const struct imx_sc_pd_soc *pd_soc;
392 	int ret;
393 
394 	ret = imx_scu_get_handle(&pm_ipc_handle);
395 	if (ret)
396 		return ret;
397 
398 	pd_soc = of_device_get_match_data(&pdev->dev);
399 	if (!pd_soc)
400 		return -ENODEV;
401 
402 	imx_sc_pd_get_console_rsrc();
403 
404 	return imx_scu_init_pm_domains(&pdev->dev, pd_soc);
405 }
406 
407 static const struct of_device_id imx_sc_pd_match[] = {
408 	{ .compatible = "fsl,imx8qxp-scu-pd", &imx8qxp_scu_pd},
409 	{ .compatible = "fsl,scu-pd", &imx8qxp_scu_pd},
410 	{ /* sentinel */ }
411 };
412 
413 static struct platform_driver imx_sc_pd_driver = {
414 	.driver = {
415 		.name = "imx-scu-pd",
416 		.of_match_table = imx_sc_pd_match,
417 	},
418 	.probe = imx_sc_pd_probe,
419 };
420 builtin_platform_driver(imx_sc_pd_driver);
421 
422 MODULE_AUTHOR("Dong Aisheng <aisheng.dong@nxp.com>");
423 MODULE_DESCRIPTION("IMX SCU Power Domain driver");
424 MODULE_LICENSE("GPL v2");
425