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 <command.h>
36 #include <asm/arch/at91sam9260.h>
37 #include <asm/arch/at91_common.h>
38 #include <asm/arch/gpio.h>
39 #include <asm/io.h>
40 #include <i2c.h>
41 #include <linux/delay.h>
42
43 #include "ethernut5_pwrman.h"
44
45 /* PMC firmware version */
46 static int pwrman_major;
47 static int pwrman_minor;
48
49 /*
50 * Enable Ethernut 5 power management.
51 *
52 * This function must be called during board initialization.
53 * While we are using u-boot's I2C subsystem, it may be required
54 * to enable the serial port before calling this function,
55 * in particular when debugging is enabled.
56 *
57 * If board specific commands are not available, we will activate
58 * all board components.
59 */
ethernut5_power_init(void)60 void ethernut5_power_init(void)
61 {
62 pwrman_minor = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_VERS);
63 pwrman_major = pwrman_minor >> 4;
64 pwrman_minor &= 15;
65
66 #ifndef CONFIG_CMD_BSP
67 /* Do not modify anything, if we do not have a known version. */
68 if (pwrman_major == 2) {
69 /* Without board specific commands we enable all features. */
70 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA, ~PWRMAN_ETHRST);
71 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS, PWRMAN_ETHRST);
72 }
73 #endif
74 }
75
76 /*
77 * Reset Ethernet PHY.
78 *
79 * This function allows the re-configure the PHY after
80 * changing its strap pins.
81 */
ethernut5_phy_reset(void)82 void ethernut5_phy_reset(void)
83 {
84 /* Do not modify anything, if we do not have a known version. */
85 if (pwrman_major != 2)
86 return;
87
88 /*
89 * Make sure that the Ethernet clock is enabled and the PHY reset
90 * is disabled for at least 100 us.
91 */
92 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA, PWRMAN_ETHCLK);
93 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS, PWRMAN_ETHRST);
94 udelay(100);
95
96 /*
97 * LAN8710 strap pins are
98 * PA14 => PHY MODE0
99 * PA15 => PHY MODE1
100 * PA17 => PHY MODE2 => 111b all capable
101 * PA18 => PHY ADDR0 => 0b
102 */
103 at91_set_pio_input(AT91_PIO_PORTA, 14, 1);
104 at91_set_pio_input(AT91_PIO_PORTA, 15, 1);
105 at91_set_pio_input(AT91_PIO_PORTA, 17, 1);
106 at91_set_pio_input(AT91_PIO_PORTA, 18, 0);
107
108 /* Activate PHY reset for 100 us. */
109 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA, PWRMAN_ETHRST);
110 udelay(100);
111 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS, PWRMAN_ETHRST);
112
113 at91_set_pio_input(AT91_PIO_PORTA, 14, 1);
114 }
115
116 /*
117 * Output the firmware version we got during initialization.
118 */
ethernut5_print_version(void)119 void ethernut5_print_version(void)
120 {
121 printf("%u.%u\n", pwrman_major, pwrman_minor);
122 }
123
124 /*
125 * All code below this point is optional and implements
126 * the 'pwrman' command.
127 */
128 #ifdef CONFIG_CMD_BSP
129
130 /* Human readable names of PMC features */
131 char *pwrman_feat[8] = {
132 "board", "vbin", "vbout", "mmc",
133 "rs232", "ethclk", "ethrst", "wakeup"
134 };
135
136 /*
137 * Print all feature names, that have its related flags enabled.
138 */
print_flagged_features(u8 flags)139 static void print_flagged_features(u8 flags)
140 {
141 int i;
142
143 for (i = 0; i < 8; i++) {
144 if (flags & (1 << i))
145 printf("%s ", pwrman_feat[i]);
146 }
147 }
148
149 /*
150 * Return flags of a given list of feature names.
151 *
152 * The function stops at the first unknown list entry and
153 * returns the number of detected names as a function result.
154 */
feature_flags(char * const names[],int num,u8 * flags)155 static int feature_flags(char * const names[], int num, u8 *flags)
156 {
157 int i, j;
158
159 *flags = 0;
160 for (i = 0; i < num; i++) {
161 for (j = 0; j < 8; j++) {
162 if (strcmp(pwrman_feat[j], names[i]) == 0) {
163 *flags |= 1 << j;
164 break;
165 }
166 }
167 if (j > 7)
168 break;
169 }
170 return i;
171 }
172
ethernut5_print_power(void)173 void ethernut5_print_power(void)
174 {
175 u8 flags;
176 int i;
177
178 flags = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA);
179 for (i = 0; i < 2; i++) {
180 if (flags) {
181 print_flagged_features(flags);
182 printf("%s\n", i ? "off" : "on");
183 }
184 flags = ~flags;
185 }
186 }
187
ethernut5_print_celsius(void)188 void ethernut5_print_celsius(void)
189 {
190 int val;
191
192 /* Read ADC value from LM50 and return Celsius degrees. */
193 val = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_TEMP);
194 val *= 5000; /* 100mV/degree with 5V reference */
195 val += 128; /* 8 bit resolution */
196 val /= 256;
197 val -= 450; /* Celsius offset, still x10 */
198 /* Output full degrees. */
199 printf("%d\n", (val + 5) / 10);
200 }
201
ethernut5_print_voltage(void)202 void ethernut5_print_voltage(void)
203 {
204 int val;
205
206 /* Read ADC value from divider and return voltage. */
207 val = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_VAUX);
208 /* Resistors are 100k and 12.1k */
209 val += 5;
210 val *= 180948;
211 val /= 100000;
212 val++;
213 /* Calculation was done in 0.1V units. */
214 printf("%d\n", (val + 5) / 10);
215 }
216
217 /*
218 * Process the board specific 'pwrman' command.
219 */
do_pwrman(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])220 int do_pwrman(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
221 {
222 u8 val;
223 int i;
224
225 if (argc == 1) {
226 ethernut5_print_power();
227 } else if (argc == 2 && strcmp(argv[1], "reset") == 0) {
228 at91_set_pio_output(AT91_PIO_PORTB, 8, 1);
229 udelay(100);
230 at91_set_pio_output(AT91_PIO_PORTB, 8, 0);
231 udelay(100000);
232 } else if (argc == 2 && strcmp(argv[1], "temp") == 0) {
233 ethernut5_print_celsius();
234 } else if (argc == 2 && strcmp(argv[1], "vaux") == 0) {
235 ethernut5_print_voltage();
236 } else if (argc == 2 && strcmp(argv[1], "version") == 0) {
237 ethernut5_print_version();
238 } else if (strcmp(argv[1], "led") == 0) {
239 /* Control the green status LED. Blink frequency unit
240 ** is 0.1s, very roughly. */
241 if (argc == 2) {
242 /* No more arguments, output current settings. */
243 val = i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_LEDCTL);
244 printf("led %u %u\n", val >> 4, val & 15);
245 } else {
246 /* First argument specifies the on-time. */
247 val = (u8) simple_strtoul(argv[2], NULL, 0);
248 val <<= 4;
249 if (argc > 3) {
250 /* Second argument specifies the off-time. */
251 val |= (u8) (simple_strtoul(argv[3], NULL, 0)
252 & 15);
253 }
254 /* Update the LED control register. */
255 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_LEDCTL, val);
256 }
257 } else {
258 /* We expect a list of features followed an optional status. */
259 argc--;
260 i = feature_flags(&argv[1], argc, &val);
261 if (argc == i) {
262 /* We got a list only, print status. */
263 val &= i2c_reg_read(PWRMAN_I2C_ADDR, PWRMAN_REG_STA);
264 if (val) {
265 if (i > 1)
266 print_flagged_features(val);
267 printf("active\n");
268 } else {
269 printf("inactive\n");
270 }
271 } else {
272 /* More arguments. */
273 if (i == 0) {
274 /* No given feature, use despensibles. */
275 val = PWRMAN_DISPENSIBLE;
276 }
277 if (strcmp(argv[i + 1], "on") == 0) {
278 /* Enable features. */
279 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_ENA,
280 val);
281 } else if (strcmp(argv[i + 1], "off") == 0) {
282 /* Disable features. */
283 i2c_reg_write(PWRMAN_I2C_ADDR, PWRMAN_REG_DIS,
284 val);
285 } else {
286 printf("Bad parameter %s\n", argv[i + 1]);
287 return 1;
288 }
289 }
290 }
291 return 0;
292 }
293
294 U_BOOT_CMD(
295 pwrman, CONFIG_SYS_MAXARGS, 1, do_pwrman,
296 "power management",
297 "- print settings\n"
298 "pwrman feature ...\n"
299 " - print status\n"
300 "pwrman [feature ...] on|off\n"
301 " - enable/disable specified or all dispensible features\n"
302 "pwrman led [on-time [off-time]]\n"
303 " - print or set led blink timer\n"
304 "pwrman temp\n"
305 " - print board temperature (Celsius)\n"
306 "pwrman vaux\n"
307 " - print auxiliary input voltage\n"
308 "pwrman reset\n"
309 " - reset power management controller\n"
310 "pwrman version\n"
311 " - print firmware version\n"
312 "\n"
313 " features, (*)=dispensible:\n"
314 " board - 1.8V and 3.3V supply\n"
315 " vbin - supply via USB device connector\n"
316 " vbout - USB host connector supply(*)\n"
317 " mmc - MMC slot supply(*)\n"
318 " rs232 - RS232 driver\n"
319 " ethclk - Ethernet PHY clock(*)\n"
320 " ethrst - Ethernet PHY reset\n"
321 " wakeup - RTC alarm"
322 );
323 #endif /* CONFIG_CMD_BSP */
324