1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2011
4  * egnite GmbH <info@egnite.de>
5  */
6 
7 /*
8  * Ethernut 5 power management support
9  *
10  * This board may be supplied via USB, IEEE 802.3af PoE or an
11  * auxiliary DC input. An on-board ATmega168 microcontroller,
12  * the so called power management controller or PMC, is used
13  * to select the supply source and to switch on and off certain
14  * energy consuming board components. This allows to reduce the
15  * total stand-by consumption to less than 70mW.
16  *
17  * The main CPU communicates with the PMC via I2C. When
18  * CONFIG_CMD_BSP is defined in the board configuration file,
19  * then the board specific command 'pwrman' becomes available,
20  * which allows to manually deal with the PMC.
21  *
22  * Two distinct registers are provided by the PMC for enabling
23  * and disabling specific features. This avoids the often seen
24  * read-modify-write cycle or shadow register requirement.
25  * Additional registers are available to query the board
26  * status and temperature, the auxiliary voltage and to control
27  * the green user LED that is integrated in the reset switch.
28  *
29  * Note, that the AVR firmware of the PMC is released under BSDL.
30  *
31  * For additional information visit the project home page at
32  * http://www.ethernut.de/
33  */
34 #include <common.h>
35 #include <asm/arch/at91sam9260.h>
36 #include <asm/arch/at91_common.h>
37 #include <asm/arch/gpio.h>
38 #include <asm/io.h>
39 #include <i2c.h>
40 
41 #include "ethernut5_pwrman.h"
42 
43 /* PMC firmware version */
44 static int pwrman_major;
45 static int pwrman_minor;
46 
47 /*
48  * Enable Ethernut 5 power management.
49  *
50  * This function must be called during board initialization.
51  * While we are using u-boot's I2C subsystem, it may be required
52  * to enable the serial port before calling this function,
53  * in particular when debugging is enabled.
54  *
55  * If board specific commands are not available, we will activate
56  * all board components.
57  */
58 void ethernut5_power_init(void)
59 {
60 	pwrman_minor = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_VERS);
61 	pwrman_major = pwrman_minor >> 4;
62 	pwrman_minor &= 15;
63 
64 #ifndef CONFIG_CMD_BSP
65 	/* Do not modify anything, if we do not have a known version. */
66 	if (pwrman_major == 2) {
67 		/* Without board specific commands we enable all features. */
68 		i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA, ~PWRMAN_ETHRST);
69 		i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS, PWRMAN_ETHRST);
70 	}
71 #endif
72 }
73 
74 /*
75  * Reset Ethernet PHY.
76  *
77  * This function allows the re-configure the PHY after
78  * changing its strap pins.
79  */
80 void ethernut5_phy_reset(void)
81 {
82 	/* Do not modify anything, if we do not have a known version. */
83 	if (pwrman_major != 2)
84 		return;
85 
86 	/*
87 	 * Make sure that the Ethernet clock is enabled and the PHY reset
88 	 * is disabled for at least 100 us.
89 	 */
90 	i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA, PWRMAN_ETHCLK);
91 	i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS, PWRMAN_ETHRST);
92 	udelay(100);
93 
94 	/*
95 	 * LAN8710 strap pins are
96 	 * PA14 => PHY MODE0
97 	 * PA15 => PHY MODE1
98 	 * PA17 => PHY MODE2 => 111b all capable
99 	 * PA18 => PHY ADDR0 => 0b
100 	 */
101 	at91_set_pio_input(AT91_PIO_PORTA, 14, 1);
102 	at91_set_pio_input(AT91_PIO_PORTA, 15, 1);
103 	at91_set_pio_input(AT91_PIO_PORTA, 17, 1);
104 	at91_set_pio_input(AT91_PIO_PORTA, 18, 0);
105 
106 	/* Activate PHY reset for 100 us. */
107 	i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA, PWRMAN_ETHRST);
108 	udelay(100);
109 	i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS, PWRMAN_ETHRST);
110 
111 	at91_set_pio_input(AT91_PIO_PORTA, 14, 1);
112 }
113 
114 /*
115  * Output the firmware version we got during initialization.
116  */
117 void ethernut5_print_version(void)
118 {
119 	printf("%u.%u\n", pwrman_major, pwrman_minor);
120 }
121 
122 /*
123  * All code below this point is optional and implements
124  * the 'pwrman' command.
125  */
126 #ifdef CONFIG_CMD_BSP
127 
128 /* Human readable names of PMC features */
129 char *pwrman_feat[8] = {
130 	"board", "vbin", "vbout", "mmc",
131 	"rs232", "ethclk", "ethrst", "wakeup"
132 };
133 
134 /*
135  * Print all feature names, that have its related flags enabled.
136  */
137 static void print_flagged_features(u8 flags)
138 {
139 	int i;
140 
141 	for (i = 0; i < 8; i++) {
142 		if (flags & (1 << i))
143 			printf("%s ", pwrman_feat[i]);
144 	}
145 }
146 
147 /*
148  * Return flags of a given list of feature names.
149  *
150  * The function stops at the first unknown list entry and
151  * returns the number of detected names as a function result.
152  */
153 static int feature_flags(char * const names[], int num, u8 *flags)
154 {
155 	int i, j;
156 
157 	*flags = 0;
158 	for (i = 0; i < num; i++) {
159 		for (j = 0; j < 8; j++) {
160 			if (strcmp(pwrman_feat[j], names[i]) == 0) {
161 				*flags |= 1 << j;
162 				break;
163 			}
164 		}
165 		if (j > 7)
166 			break;
167 	}
168 	return i;
169 }
170 
171 void ethernut5_print_power(void)
172 {
173 	u8 flags;
174 	int i;
175 
176 	flags = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA);
177 	for (i = 0; i < 2; i++) {
178 		if (flags) {
179 			print_flagged_features(flags);
180 			printf("%s\n", i ? "off" : "on");
181 		}
182 		flags = ~flags;
183 	}
184 }
185 
186 void ethernut5_print_celsius(void)
187 {
188 	int val;
189 
190 	/* Read ADC value from LM50 and return Celsius degrees. */
191 	val = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_TEMP);
192 	val *= 5000;	/* 100mV/degree with 5V reference */
193 	val += 128;	/* 8 bit resolution */
194 	val /= 256;
195 	val -= 450;	/* Celsius offset, still x10 */
196 	/* Output full degrees. */
197 	printf("%d\n", (val + 5) / 10);
198 }
199 
200 void ethernut5_print_voltage(void)
201 {
202 	int val;
203 
204 	/* Read ADC value from divider and return voltage. */
205 	val = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_VAUX);
206 	/* Resistors are 100k and 12.1k */
207 	val += 5;
208 	val *= 180948;
209 	val /= 100000;
210 	val++;
211 	/* Calculation was done in 0.1V units. */
212 	printf("%d\n", (val + 5) / 10);
213 }
214 
215 /*
216  * Process the board specific 'pwrman' command.
217  */
218 int do_pwrman(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
219 {
220 	u8 val;
221 	int i;
222 
223 	if (argc == 1) {
224 		ethernut5_print_power();
225 	} else if (argc == 2 && strcmp(argv[1], "reset") == 0) {
226 		at91_set_pio_output(AT91_PIO_PORTB, 8, 1);
227 		udelay(100);
228 		at91_set_pio_output(AT91_PIO_PORTB, 8, 0);
229 		udelay(100000);
230 	} else if (argc == 2 && strcmp(argv[1], "temp") == 0) {
231 		ethernut5_print_celsius();
232 	} else if (argc == 2 && strcmp(argv[1], "vaux") == 0) {
233 		ethernut5_print_voltage();
234 	} else if (argc == 2 && strcmp(argv[1], "version") == 0) {
235 		ethernut5_print_version();
236 	} else if (strcmp(argv[1], "led") == 0) {
237 		/* Control the green status LED. Blink frequency unit
238 		** is 0.1s, very roughly. */
239 		if (argc == 2) {
240 			/* No more arguments, output current settings. */
241 			val = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_LEDCTL);
242 			printf("led %u %u\n", val >> 4, val & 15);
243 		} else {
244 			/* First argument specifies the on-time. */
245 			val = (u8) simple_strtoul(argv[2], NULL, 0);
246 			val <<= 4;
247 			if (argc > 3) {
248 				/* Second argument specifies the off-time. */
249 				val |= (u8) (simple_strtoul(argv[3], NULL, 0)
250 						& 15);
251 			}
252 			/* Update the LED control register. */
253 			i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_LEDCTL, val);
254 		}
255 	} else {
256 		/* We expect a list of features followed an optional status. */
257 		argc--;
258 		i = feature_flags(&argv[1], argc, &val);
259 		if (argc == i) {
260 			/* We got a list only, print status. */
261 			val &= i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_STA);
262 			if (val) {
263 				if (i > 1)
264 					print_flagged_features(val);
265 				printf("active\n");
266 			} else {
267 				printf("inactive\n");
268 			}
269 		} else {
270 			/* More arguments. */
271 			if (i == 0) {
272 				/* No given feature, use despensibles. */
273 				val = PWRMAN_DISPENSIBLE;
274 			}
275 			if (strcmp(argv[i + 1], "on") == 0) {
276 				/* Enable features. */
277 				i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA,
278 						val);
279 			} else if (strcmp(argv[i + 1], "off") == 0) {
280 				/* Disable features. */
281 				i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS,
282 						val);
283 			} else {
284 				printf("Bad parameter %s\n", argv[i + 1]);
285 				return 1;
286 			}
287 		}
288 	}
289 	return 0;
290 }
291 
292 U_BOOT_CMD(
293 	pwrman,	CONFIG_SYS_MAXARGS, 1, do_pwrman,
294 	"power management",
295 		   "- print settings\n"
296 	"pwrman feature ...\n"
297 	"       - print status\n"
298 	"pwrman [feature ...] on|off\n"
299 	"       - enable/disable specified or all dispensible features\n"
300 	"pwrman led [on-time [off-time]]\n"
301 	"       - print or set led blink timer\n"
302 	"pwrman temp\n"
303 	"       - print board temperature (Celsius)\n"
304 	"pwrman vaux\n"
305 	"       - print auxiliary input voltage\n"
306 	"pwrman reset\n"
307 	"       - reset power management controller\n"
308 	"pwrman version\n"
309 	"       - print firmware version\n"
310 	"\n"
311 	"        features, (*)=dispensible:\n"
312 	"          board  - 1.8V and 3.3V supply\n"
313 	"          vbin   - supply via USB device connector\n"
314 	"          vbout  - USB host connector supply(*)\n"
315 	"          mmc    - MMC slot supply(*)\n"
316 	"          rs232  - RS232 driver\n"
317 	"          ethclk - Ethernet PHY clock(*)\n"
318 	"          ethrst - Ethernet PHY reset\n"
319 	"          wakeup - RTC alarm"
320 );
321 #endif /* CONFIG_CMD_BSP */
322