1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015 Samsung Electronics
4  * Przemyslaw Marczak <p.marczak@samsung.com>
5  */
6 
7 #include <common.h>
8 #include <adc.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <fdtdec.h>
12 #include <asm/global_data.h>
13 #include <linux/delay.h>
14 #include <power/pmic.h>
15 #include <power/regulator.h>
16 #include <power/s2mps11.h>
17 #include <samsung/exynos5-dt-types.h>
18 #include <samsung/misc.h>
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 static const struct udevice_id board_ids[] = {
23 	{ .compatible = "samsung,odroidxu3", .data = EXYNOS5_BOARD_ODROID_XU3 },
24 	{ .compatible = "samsung,exynos5", .data = EXYNOS5_BOARD_GENERIC },
25 	{ },
26 };
27 
28 /**
29  * Odroix XU3/XU4/HC1/HC2 board revisions (from HC1+_HC2_MAIN_REV0.1_20171017.pdf):
30  * Rev   ADCmax  Board
31  * 0.1     0     XU3 0.1
32  * 0.2   372     XU3 0.2 | XU3L - no DISPLAYPORT (probe I2C0:0x40 / INA231)
33  * 0.3  1280     XU4 0.1
34  * 0.4   739     XU4 0.2
35  * 0.5  1016     XU4+Air0.1 (Passive cooling)
36  * 0.6  1309     XU4-HC1 0.1
37  * 0.7  1470     XU4-HC1+ 0.1 (HC2)
38  * Use +1% for ADC value tolerance in the array below, the code loops until
39  * the measured ADC value is lower than then ADCmax from the array.
40  */
41 struct odroid_rev_info odroid_info[] = {
42 	{ EXYNOS5_BOARD_ODROID_XU3_REV01, 1, 10, "xu3" },
43 	{ EXYNOS5_BOARD_ODROID_XU3_REV02, 2, 375, "xu3" },
44 	{ EXYNOS5_BOARD_ODROID_XU4_REV01, 1, 1293, "xu4" },
45 	{ EXYNOS5_BOARD_ODROID_HC1_REV01, 1, 1322, "hc1" },
46 	{ EXYNOS5_BOARD_ODROID_HC2_REV01, 1, 1484, "hc1" },
47 	{ EXYNOS5_BOARD_ODROID_UNKNOWN, 0, 4095, "unknown" },
48 };
49 
50 /*
51  * Read ADC at least twice and check the resuls.  If regulator providing voltage
52  * on to measured point was just turned on, first reads might require time
53  * to stabilize.
54  */
odroid_get_adc_val(unsigned int * adcval)55 static int odroid_get_adc_val(unsigned int *adcval)
56 {
57 	unsigned int adcval_prev = 0;
58 	int ret, retries = 20;
59 
60 	ret = adc_channel_single_shot("adc@12D10000", CONFIG_ODROID_REV_AIN,
61 				      &adcval_prev);
62 	if (ret)
63 		return ret;
64 
65 	while (retries--) {
66 		mdelay(5);
67 
68 		ret = adc_channel_single_shot("adc@12D10000",
69 					      CONFIG_ODROID_REV_AIN, adcval);
70 		if (ret)
71 			return ret;
72 
73 		/*
74 		 * If difference between ADC reads is less than 3%,
75 		 * accept the result
76 		 */
77 		if ((100 * abs(*adcval - adcval_prev) / adcval_prev) < 3)
78 			return ret;
79 
80 		adcval_prev = *adcval;
81 	}
82 
83 	return ret;
84 }
85 
odroid_get_board_type(void)86 static int odroid_get_board_type(void)
87 {
88 	unsigned int adcval;
89 	int ret, i;
90 
91 	ret = odroid_get_adc_val(&adcval);
92 	if (ret)
93 		goto rev_default;
94 
95 	for (i = 0; i < ARRAY_SIZE(odroid_info); i++) {
96 		/* ADC tolerance: +1% */
97 		if (adcval < odroid_info[i].adc_val)
98 			return odroid_info[i].board_type;
99 	}
100 
101 rev_default:
102 	return EXYNOS5_BOARD_ODROID_XU3;
103 }
104 
105 /**
106  * odroid_get_type_str - returns pointer to one of the board type string.
107  * Board types: "xu3", "xu3-lite", "xu4". However the "xu3lite" can be
108  * detected only when the i2c controller is ready to use. Fortunately,
109  * XU3 and XU3L are compatible, and the information about board lite
110  * revision is needed before booting the linux, to set proper environment
111  * variable: $fdtfile.
112  */
odroid_get_type_str(void)113 static const char *odroid_get_type_str(void)
114 {
115 	const char *type_xu3l = "xu3-lite";
116 	struct udevice *dev, *chip;
117 	int i, ret;
118 
119 	if (gd->board_type != EXYNOS5_BOARD_ODROID_XU3_REV02)
120 		goto exit;
121 
122 	ret = pmic_get("s2mps11_pmic@66", &dev);
123 	if (ret)
124 		goto exit;
125 
126 	/* Enable LDO26: 3.0V */
127 	ret = pmic_reg_write(dev, S2MPS11_REG_L26CTRL,
128 			     S2MPS11_LDO26_ENABLE);
129 	if (ret)
130 		goto exit;
131 
132 	/* Check XU3Lite by probe INA231 I2C0:0x40 */
133 	ret = uclass_get_device(UCLASS_I2C, 0, &dev);
134 	if (ret)
135 		goto exit;
136 
137 	ret = dm_i2c_probe(dev, 0x40, 0x0, &chip);
138 	if (ret)
139 		return type_xu3l;
140 
141 exit:
142 	for (i = 0; i < ARRAY_SIZE(odroid_info); i++) {
143 		if (odroid_info[i].board_type == gd->board_type)
144 			return odroid_info[i].name;
145 	}
146 
147 	return NULL;
148 }
149 
board_is_odroidxu3(void)150 bool board_is_odroidxu3(void)
151 {
152 	if (gd->board_type >= EXYNOS5_BOARD_ODROID_XU3 &&
153 	    gd->board_type <= EXYNOS5_BOARD_ODROID_XU3_REV02)
154 		return true;
155 
156 	return false;
157 }
158 
board_is_odroidxu4(void)159 bool board_is_odroidxu4(void)
160 {
161 	if (gd->board_type == EXYNOS5_BOARD_ODROID_XU4_REV01)
162 		return true;
163 
164 	return false;
165 }
166 
board_is_odroidhc1(void)167 bool board_is_odroidhc1(void)
168 {
169 	if (gd->board_type == EXYNOS5_BOARD_ODROID_HC1_REV01)
170 		return true;
171 
172 	return false;
173 }
174 
board_is_odroidhc2(void)175 bool board_is_odroidhc2(void)
176 {
177 	if (gd->board_type == EXYNOS5_BOARD_ODROID_HC2_REV01)
178 		return true;
179 
180 	return false;
181 }
182 
board_is_generic(void)183 bool board_is_generic(void)
184 {
185 	if (gd->board_type == EXYNOS5_BOARD_GENERIC)
186 		return true;
187 
188 	return false;
189 }
190 
191 #ifdef CONFIG_REVISION_TAG
odroid_get_rev(void)192 static unsigned int odroid_get_rev(void)
193 {
194 	int i;
195 
196 	for (i = 0; i < ARRAY_SIZE(odroid_info); i++) {
197 		if (odroid_info[i].board_type == gd->board_type)
198 			return odroid_info[i].board_rev;
199 	}
200 
201 	return 0;
202 }
203 
204 /**
205  * get_board_rev() - return detected board revision.
206  *
207  * @return:  return board revision number for XU3 or 0 for generic
208  */
get_board_rev(void)209 u32 get_board_rev(void)
210 {
211 	if (board_is_generic())
212 		return 0;
213 
214 	return odroid_get_rev();
215 }
216 #endif
217 
218 /**
219  * get_board_type() - returns board type string.
220  *
221  * @return:  return board type string for XU3 or empty string for generic
222  */
get_board_type(void)223 const char *get_board_type(void)
224 {
225 	const char *generic = "";
226 
227 	if (board_is_generic())
228 		return generic;
229 
230 	return odroid_get_type_str();
231 }
232 
233 /**
234  * set_board_type() - set board type in gd->board_type.
235  * As default type set EXYNOS5_BOARD_GENERIC. If Odroid is detected,
236  * set its proper type based on device tree.
237  *
238  * This might be called early when some more specific ways to detect revision
239  * are not yet available.
240  */
set_board_type(void)241 void set_board_type(void)
242 {
243 	const struct udevice_id *of_match = board_ids;
244 	int ret;
245 
246 	gd->board_type = EXYNOS5_BOARD_GENERIC;
247 
248 	while (of_match->compatible) {
249 		ret = fdt_node_check_compatible(gd->fdt_blob, 0,
250 						of_match->compatible);
251 		if (ret)
252 			of_match++;
253 
254 		gd->board_type = of_match->data;
255 		break;
256 	}
257 }
258 
259 /**
260  * set_board_revision() - set detailed board type in gd->board_type.
261  * Should be called when resources (e.g. regulators) are available
262  * so ADC can be used to detect the specific revision of a board.
263  */
set_board_revision(void)264 void set_board_revision(void)
265 {
266 	if (board_is_odroidxu3())
267 		gd->board_type = odroid_get_board_type();
268 }
269