1 /*
2  * Copyright (c) 2017-2021, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <errno.h>
9 
10 #include <libfdt.h>
11 
12 #include <platform_def.h>
13 
14 #include <common/debug.h>
15 #include <common/fdt_wrappers.h>
16 #include <drivers/st/stm32_gpio.h>
17 #include <drivers/st/stm32mp1_ddr.h>
18 #include <drivers/st/stm32mp1_ram.h>
19 
20 #include <stm32mp_dt.h>
21 
22 static void *fdt;
23 
24 /*******************************************************************************
25  * This function checks device tree file with its header.
26  * Returns 0 on success and a negative FDT error code on failure.
27  ******************************************************************************/
dt_open_and_check(uintptr_t dt_addr)28 int dt_open_and_check(uintptr_t dt_addr)
29 {
30 	int ret;
31 
32 	ret = fdt_check_header((void *)dt_addr);
33 	if (ret == 0) {
34 		fdt = (void *)dt_addr;
35 	}
36 
37 	return ret;
38 }
39 
40 /*******************************************************************************
41  * This function gets the address of the DT.
42  * If DT is OK, fdt_addr is filled with DT address.
43  * Returns 1 if success, 0 otherwise.
44  ******************************************************************************/
fdt_get_address(void ** fdt_addr)45 int fdt_get_address(void **fdt_addr)
46 {
47 	if (fdt == NULL) {
48 		return 0;
49 	}
50 
51 	*fdt_addr = fdt;
52 
53 	return 1;
54 }
55 
56 /*******************************************************************************
57  * This function check the presence of a node (generic use of fdt library).
58  * Returns true if present, else return false.
59  ******************************************************************************/
fdt_check_node(int node)60 bool fdt_check_node(int node)
61 {
62 	int len;
63 	const char *cchar;
64 
65 	cchar = fdt_get_name(fdt, node, &len);
66 
67 	return (cchar != NULL) && (len >= 0);
68 }
69 
70 /*******************************************************************************
71  * This function return global node status (generic use of fdt library).
72  ******************************************************************************/
fdt_get_status(int node)73 uint8_t fdt_get_status(int node)
74 {
75 	uint8_t status = DT_DISABLED;
76 	const char *cchar;
77 
78 	cchar = fdt_getprop(fdt, node, "status", NULL);
79 	if ((cchar == NULL) ||
80 	    (strncmp(cchar, "okay", strlen("okay")) == 0)) {
81 		status |= DT_NON_SECURE;
82 	}
83 
84 	cchar = fdt_getprop(fdt, node, "secure-status", NULL);
85 	if (cchar == NULL) {
86 		if (status == DT_NON_SECURE) {
87 			status |= DT_SECURE;
88 		}
89 	} else if (strncmp(cchar, "okay", strlen("okay")) == 0) {
90 		status |= DT_SECURE;
91 	}
92 
93 	return status;
94 }
95 
96 #if ENABLE_ASSERTIONS
97 /*******************************************************************************
98  * This function returns the address cells from the node parent.
99  * Returns:
100  * - #address-cells value if success.
101  * - invalid value if error.
102  * - a default value if undefined #address-cells property as per libfdt
103  *   implementation.
104  ******************************************************************************/
fdt_get_node_parent_address_cells(int node)105 static int fdt_get_node_parent_address_cells(int node)
106 {
107 	int parent;
108 
109 	parent = fdt_parent_offset(fdt, node);
110 	if (parent < 0) {
111 		return -FDT_ERR_NOTFOUND;
112 	}
113 
114 	return fdt_address_cells(fdt, parent);
115 }
116 #endif
117 
118 /*******************************************************************************
119  * This function gets the stdout pin configuration information from the DT.
120  * And then calls the sub-function to treat it and set GPIO registers.
121  * Returns 0 on success and a negative FDT error code on failure.
122  ******************************************************************************/
dt_set_stdout_pinctrl(void)123 int dt_set_stdout_pinctrl(void)
124 {
125 	int node;
126 
127 	node = fdt_get_stdout_node_offset(fdt);
128 	if (node < 0) {
129 		return -FDT_ERR_NOTFOUND;
130 	}
131 
132 	return dt_set_pinctrl_config(node);
133 }
134 
135 /*******************************************************************************
136  * This function fills the generic information from a given node.
137  ******************************************************************************/
dt_fill_device_info(struct dt_node_info * info,int node)138 void dt_fill_device_info(struct dt_node_info *info, int node)
139 {
140 	const fdt32_t *cuint;
141 
142 	assert(fdt_get_node_parent_address_cells(node) == 1);
143 
144 	cuint = fdt_getprop(fdt, node, "reg", NULL);
145 	if (cuint != NULL) {
146 		info->base = fdt32_to_cpu(*cuint);
147 	} else {
148 		info->base = 0;
149 	}
150 
151 	cuint = fdt_getprop(fdt, node, "clocks", NULL);
152 	if (cuint != NULL) {
153 		cuint++;
154 		info->clock = (int)fdt32_to_cpu(*cuint);
155 	} else {
156 		info->clock = -1;
157 	}
158 
159 	cuint = fdt_getprop(fdt, node, "resets", NULL);
160 	if (cuint != NULL) {
161 		cuint++;
162 		info->reset = (int)fdt32_to_cpu(*cuint);
163 	} else {
164 		info->reset = -1;
165 	}
166 
167 	info->status = fdt_get_status(node);
168 }
169 
170 /*******************************************************************************
171  * This function retrieve the generic information from DT.
172  * Returns node on success and a negative FDT error code on failure.
173  ******************************************************************************/
dt_get_node(struct dt_node_info * info,int offset,const char * compat)174 int dt_get_node(struct dt_node_info *info, int offset, const char *compat)
175 {
176 	int node;
177 
178 	node = fdt_node_offset_by_compatible(fdt, offset, compat);
179 	if (node < 0) {
180 		return -FDT_ERR_NOTFOUND;
181 	}
182 
183 	dt_fill_device_info(info, node);
184 
185 	return node;
186 }
187 
188 /*******************************************************************************
189  * This function gets the UART instance info of stdout from the DT.
190  * Returns node on success and a negative FDT error code on failure.
191  ******************************************************************************/
dt_get_stdout_uart_info(struct dt_node_info * info)192 int dt_get_stdout_uart_info(struct dt_node_info *info)
193 {
194 	int node;
195 
196 	node = fdt_get_stdout_node_offset(fdt);
197 	if (node < 0) {
198 		return -FDT_ERR_NOTFOUND;
199 	}
200 
201 	dt_fill_device_info(info, node);
202 
203 	return node;
204 }
205 
206 /*******************************************************************************
207  * This function gets DDR size information from the DT.
208  * Returns value in bytes on success, and 0 on failure.
209  ******************************************************************************/
dt_get_ddr_size(void)210 uint32_t dt_get_ddr_size(void)
211 {
212 	static uint32_t size;
213 	int node;
214 
215 	if (size != 0U) {
216 		return size;
217 	}
218 
219 	node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
220 	if (node < 0) {
221 		INFO("%s: Cannot read DDR node in DT\n", __func__);
222 		return 0;
223 	}
224 
225 	size = fdt_read_uint32_default(fdt, node, "st,mem-size", 0U);
226 
227 	flush_dcache_range((uintptr_t)&size, sizeof(uint32_t));
228 
229 	return size;
230 }
231 
232 /*******************************************************************************
233  * This function gets PWR VDD regulator voltage information from the DT.
234  * Returns value in microvolts on success, and 0 on failure.
235  ******************************************************************************/
dt_get_pwr_vdd_voltage(void)236 uint32_t dt_get_pwr_vdd_voltage(void)
237 {
238 	int node, pwr_regulators_node;
239 	const fdt32_t *cuint;
240 
241 	node = fdt_node_offset_by_compatible(fdt, -1, DT_PWR_COMPAT);
242 	if (node < 0) {
243 		INFO("%s: Cannot read PWR node in DT\n", __func__);
244 		return 0;
245 	}
246 
247 	pwr_regulators_node = fdt_subnode_offset(fdt, node, "pwr-regulators");
248 	if (pwr_regulators_node < 0) {
249 		INFO("%s: Cannot read pwr-regulators node in DT\n", __func__);
250 		return 0;
251 	}
252 
253 	cuint = fdt_getprop(fdt, pwr_regulators_node, "vdd-supply", NULL);
254 	if (cuint == NULL) {
255 		return 0;
256 	}
257 
258 	node = fdt_node_offset_by_phandle(fdt, fdt32_to_cpu(*cuint));
259 	if (node < 0) {
260 		return 0;
261 	}
262 
263 	cuint = fdt_getprop(fdt, node, "regulator-min-microvolt", NULL);
264 	if (cuint == NULL) {
265 		return 0;
266 	}
267 
268 	return fdt32_to_cpu(*cuint);
269 }
270 
271 /*******************************************************************************
272  * This function retrieves board model from DT
273  * Returns string taken from model node, NULL otherwise
274  ******************************************************************************/
dt_get_board_model(void)275 const char *dt_get_board_model(void)
276 {
277 	int node = fdt_path_offset(fdt, "/");
278 
279 	if (node < 0) {
280 		return NULL;
281 	}
282 
283 	return (const char *)fdt_getprop(fdt, node, "model", NULL);
284 }
285 
286 /*******************************************************************************
287  * This function gets the pin count for a GPIO bank based from the FDT.
288  * It also checks node consistency.
289  ******************************************************************************/
fdt_get_gpio_bank_pin_count(unsigned int bank)290 int fdt_get_gpio_bank_pin_count(unsigned int bank)
291 {
292 	int pinctrl_node;
293 	int node;
294 	uint32_t bank_offset;
295 
296 	pinctrl_node = stm32_get_gpio_bank_pinctrl_node(fdt, bank);
297 	if (pinctrl_node < 0) {
298 		return -FDT_ERR_NOTFOUND;
299 	}
300 
301 	bank_offset = stm32_get_gpio_bank_offset(bank);
302 
303 	fdt_for_each_subnode(node, fdt, pinctrl_node) {
304 		const fdt32_t *cuint;
305 
306 		if (fdt_getprop(fdt, node, "gpio-controller", NULL) == NULL) {
307 			continue;
308 		}
309 
310 		cuint = fdt_getprop(fdt, node, "reg", NULL);
311 		if (cuint == NULL) {
312 			continue;
313 		}
314 
315 		if (fdt32_to_cpu(*cuint) != bank_offset) {
316 			continue;
317 		}
318 
319 		if (fdt_get_status(node) == DT_DISABLED) {
320 			return 0;
321 		}
322 
323 		cuint = fdt_getprop(fdt, node, "ngpios", NULL);
324 		if (cuint == NULL) {
325 			return -FDT_ERR_NOTFOUND;
326 		}
327 
328 		return (int)fdt32_to_cpu(*cuint);
329 	}
330 
331 	return 0;
332 }
333