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 */
46static int pwrman_major;
47static 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 */
60void 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 */
82void 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 */
119void 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 */
131char *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 */
139static 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 */
155static 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
173void 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
188void 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
202void 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 */
220int 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
294U_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