1 /*
2  * Copyright (c) 2016-2020, STMicroelectronics - All Rights Reserved
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <errno.h>
9 #include <stdbool.h>
10 
11 #include <libfdt.h>
12 
13 #include <platform_def.h>
14 
15 #include <common/bl_common.h>
16 #include <common/debug.h>
17 #include <drivers/st/stm32_gpio.h>
18 #include <drivers/st/stm32mp_clkfunc.h>
19 #include <lib/mmio.h>
20 #include <lib/utils_def.h>
21 
22 #define DT_GPIO_BANK_SHIFT	12
23 #define DT_GPIO_BANK_MASK	GENMASK(16, 12)
24 #define DT_GPIO_PIN_SHIFT	8
25 #define DT_GPIO_PIN_MASK	GENMASK(11, 8)
26 #define DT_GPIO_MODE_MASK	GENMASK(7, 0)
27 
28 /*******************************************************************************
29  * This function gets GPIO bank node in DT.
30  * Returns node offset if status is okay in DT, else return 0
31  ******************************************************************************/
ckeck_gpio_bank(void * fdt,uint32_t bank,int pinctrl_node)32 static int ckeck_gpio_bank(void *fdt, uint32_t bank, int pinctrl_node)
33 {
34 	int pinctrl_subnode;
35 	uint32_t bank_offset = stm32_get_gpio_bank_offset(bank);
36 
37 	fdt_for_each_subnode(pinctrl_subnode, fdt, pinctrl_node) {
38 		const fdt32_t *cuint;
39 
40 		if (fdt_getprop(fdt, pinctrl_subnode,
41 				"gpio-controller", NULL) == NULL) {
42 			continue;
43 		}
44 
45 		cuint = fdt_getprop(fdt, pinctrl_subnode, "reg", NULL);
46 		if (cuint == NULL) {
47 			continue;
48 		}
49 
50 		if ((fdt32_to_cpu(*cuint) == bank_offset) &&
51 		    (fdt_get_status(pinctrl_subnode) != DT_DISABLED)) {
52 			return pinctrl_subnode;
53 		}
54 	}
55 
56 	return 0;
57 }
58 
59 /*******************************************************************************
60  * This function gets the pin settings from DT information.
61  * When analyze and parsing is done, set the GPIO registers.
62  * Returns 0 on success and a negative FDT error code on failure.
63  ******************************************************************************/
dt_set_gpio_config(void * fdt,int node,uint8_t status)64 static int dt_set_gpio_config(void *fdt, int node, uint8_t status)
65 {
66 	const fdt32_t *cuint, *slewrate;
67 	int len;
68 	int pinctrl_node;
69 	uint32_t i;
70 	uint32_t speed = GPIO_SPEED_LOW;
71 	uint32_t pull = GPIO_NO_PULL;
72 
73 	cuint = fdt_getprop(fdt, node, "pinmux", &len);
74 	if (cuint == NULL) {
75 		return -FDT_ERR_NOTFOUND;
76 	}
77 
78 	pinctrl_node = fdt_parent_offset(fdt, fdt_parent_offset(fdt, node));
79 	if (pinctrl_node < 0) {
80 		return -FDT_ERR_NOTFOUND;
81 	}
82 
83 	slewrate = fdt_getprop(fdt, node, "slew-rate", NULL);
84 	if (slewrate != NULL) {
85 		speed = fdt32_to_cpu(*slewrate);
86 	}
87 
88 	if (fdt_getprop(fdt, node, "bias-pull-up", NULL) != NULL) {
89 		pull = GPIO_PULL_UP;
90 	} else if (fdt_getprop(fdt, node, "bias-pull-down", NULL) != NULL) {
91 		pull = GPIO_PULL_DOWN;
92 	} else {
93 		VERBOSE("No bias configured in node %d\n", node);
94 	}
95 
96 	for (i = 0U; i < ((uint32_t)len / sizeof(uint32_t)); i++) {
97 		uint32_t pincfg;
98 		uint32_t bank;
99 		uint32_t pin;
100 		uint32_t mode;
101 		uint32_t alternate = GPIO_ALTERNATE_(0);
102 		int bank_node;
103 		int clk;
104 
105 		pincfg = fdt32_to_cpu(*cuint);
106 		cuint++;
107 
108 		bank = (pincfg & DT_GPIO_BANK_MASK) >> DT_GPIO_BANK_SHIFT;
109 
110 		pin = (pincfg & DT_GPIO_PIN_MASK) >> DT_GPIO_PIN_SHIFT;
111 
112 		mode = pincfg & DT_GPIO_MODE_MASK;
113 
114 		switch (mode) {
115 		case 0:
116 			mode = GPIO_MODE_INPUT;
117 			break;
118 		case 1 ... 16:
119 			alternate = mode - 1U;
120 			mode = GPIO_MODE_ALTERNATE;
121 			break;
122 		case 17:
123 			mode = GPIO_MODE_ANALOG;
124 			break;
125 		default:
126 			mode = GPIO_MODE_OUTPUT;
127 			break;
128 		}
129 
130 		if (fdt_getprop(fdt, node, "drive-open-drain", NULL) != NULL) {
131 			mode |= GPIO_OPEN_DRAIN;
132 		}
133 
134 		bank_node = ckeck_gpio_bank(fdt, bank, pinctrl_node);
135 		if (bank_node == 0) {
136 			ERROR("PINCTRL inconsistent in DT\n");
137 			panic();
138 		}
139 
140 		clk = fdt_get_clock_id(bank_node);
141 		if (clk < 0) {
142 			return -FDT_ERR_NOTFOUND;
143 		}
144 
145 		/* Platform knows the clock: assert it is okay */
146 		assert((unsigned long)clk == stm32_get_gpio_bank_clock(bank));
147 
148 		set_gpio(bank, pin, mode, speed, pull, alternate, status);
149 	}
150 
151 	return 0;
152 }
153 
154 /*******************************************************************************
155  * This function gets the pin settings from DT information.
156  * When analyze and parsing is done, set the GPIO registers.
157  * Returns 0 on success and a negative FDT/ERRNO error code on failure.
158  ******************************************************************************/
dt_set_pinctrl_config(int node)159 int dt_set_pinctrl_config(int node)
160 {
161 	const fdt32_t *cuint;
162 	int lenp = 0;
163 	uint32_t i;
164 	uint8_t status;
165 	void *fdt;
166 
167 	if (fdt_get_address(&fdt) == 0) {
168 		return -FDT_ERR_NOTFOUND;
169 	}
170 
171 	status = fdt_get_status(node);
172 	if (status == DT_DISABLED) {
173 		return -FDT_ERR_NOTFOUND;
174 	}
175 
176 	cuint = fdt_getprop(fdt, node, "pinctrl-0", &lenp);
177 	if (cuint == NULL) {
178 		return -FDT_ERR_NOTFOUND;
179 	}
180 
181 	for (i = 0; i < ((uint32_t)lenp / 4U); i++) {
182 		int p_node, p_subnode;
183 
184 		p_node = fdt_node_offset_by_phandle(fdt, fdt32_to_cpu(*cuint));
185 		if (p_node < 0) {
186 			return -FDT_ERR_NOTFOUND;
187 		}
188 
189 		fdt_for_each_subnode(p_subnode, fdt, p_node) {
190 			int ret = dt_set_gpio_config(fdt, p_subnode, status);
191 
192 			if (ret < 0) {
193 				return ret;
194 			}
195 		}
196 
197 		cuint++;
198 	}
199 
200 	return 0;
201 }
202 
set_gpio(uint32_t bank,uint32_t pin,uint32_t mode,uint32_t speed,uint32_t pull,uint32_t alternate,uint8_t status)203 void set_gpio(uint32_t bank, uint32_t pin, uint32_t mode, uint32_t speed,
204 	      uint32_t pull, uint32_t alternate, uint8_t status)
205 {
206 	uintptr_t base = stm32_get_gpio_bank_base(bank);
207 	unsigned long clock = stm32_get_gpio_bank_clock(bank);
208 
209 	assert(pin <= GPIO_PIN_MAX);
210 
211 	stm32mp_clk_enable(clock);
212 
213 	mmio_clrbits_32(base + GPIO_MODE_OFFSET,
214 			((uint32_t)GPIO_MODE_MASK << (pin << 1)));
215 	mmio_setbits_32(base + GPIO_MODE_OFFSET,
216 			(mode & ~GPIO_OPEN_DRAIN) << (pin << 1));
217 
218 	if ((mode & GPIO_OPEN_DRAIN) != 0U) {
219 		mmio_setbits_32(base + GPIO_TYPE_OFFSET, BIT(pin));
220 	} else {
221 		mmio_clrbits_32(base + GPIO_TYPE_OFFSET, BIT(pin));
222 	}
223 
224 	mmio_clrbits_32(base + GPIO_SPEED_OFFSET,
225 			((uint32_t)GPIO_SPEED_MASK << (pin << 1)));
226 	mmio_setbits_32(base + GPIO_SPEED_OFFSET, speed << (pin << 1));
227 
228 	mmio_clrbits_32(base + GPIO_PUPD_OFFSET,
229 			((uint32_t)GPIO_PULL_MASK << (pin << 1)));
230 	mmio_setbits_32(base + GPIO_PUPD_OFFSET, pull << (pin << 1));
231 
232 	if (pin < GPIO_ALT_LOWER_LIMIT) {
233 		mmio_clrbits_32(base + GPIO_AFRL_OFFSET,
234 				((uint32_t)GPIO_ALTERNATE_MASK << (pin << 2)));
235 		mmio_setbits_32(base + GPIO_AFRL_OFFSET,
236 				alternate << (pin << 2));
237 	} else {
238 		mmio_clrbits_32(base + GPIO_AFRH_OFFSET,
239 				((uint32_t)GPIO_ALTERNATE_MASK <<
240 				 ((pin - GPIO_ALT_LOWER_LIMIT) << 2)));
241 		mmio_setbits_32(base + GPIO_AFRH_OFFSET,
242 				alternate << ((pin - GPIO_ALT_LOWER_LIMIT) <<
243 					      2));
244 	}
245 
246 	VERBOSE("GPIO %u mode set to 0x%x\n", bank,
247 		mmio_read_32(base + GPIO_MODE_OFFSET));
248 	VERBOSE("GPIO %u speed set to 0x%x\n", bank,
249 		mmio_read_32(base + GPIO_SPEED_OFFSET));
250 	VERBOSE("GPIO %u mode pull to 0x%x\n", bank,
251 		mmio_read_32(base + GPIO_PUPD_OFFSET));
252 	VERBOSE("GPIO %u mode alternate low to 0x%x\n", bank,
253 		mmio_read_32(base + GPIO_AFRL_OFFSET));
254 	VERBOSE("GPIO %u mode alternate high to 0x%x\n", bank,
255 		mmio_read_32(base + GPIO_AFRH_OFFSET));
256 
257 	stm32mp_clk_disable(clock);
258 
259 	if (status == DT_SECURE) {
260 		stm32mp_register_secure_gpio(bank, pin);
261 		set_gpio_secure_cfg(bank, pin, true);
262 
263 	} else {
264 		stm32mp_register_non_secure_gpio(bank, pin);
265 		set_gpio_secure_cfg(bank, pin, false);
266 	}
267 }
268 
set_gpio_secure_cfg(uint32_t bank,uint32_t pin,bool secure)269 void set_gpio_secure_cfg(uint32_t bank, uint32_t pin, bool secure)
270 {
271 	uintptr_t base = stm32_get_gpio_bank_base(bank);
272 	unsigned long clock = stm32_get_gpio_bank_clock(bank);
273 
274 	assert(pin <= GPIO_PIN_MAX);
275 
276 	stm32mp_clk_enable(clock);
277 
278 	if (secure) {
279 		mmio_setbits_32(base + GPIO_SECR_OFFSET, BIT(pin));
280 	} else {
281 		mmio_clrbits_32(base + GPIO_SECR_OFFSET, BIT(pin));
282 	}
283 
284 	stm32mp_clk_disable(clock);
285 }
286