xref: /openbmc/linux/arch/powerpc/platforms/44x/warp.c (revision 1c96fcdef8c7492ecf34ed70102a1ae5253ef9d1)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * PIKA Warp(tm) board specific routines
4  *
5  * Copyright (c) 2008-2009 PIKA Technologies
6  *   Sean MacLennan <smaclennan@pikatech.com>
7  */
8 #include <linux/err.h>
9 #include <linux/init.h>
10 #include <linux/of_platform.h>
11 #include <linux/kthread.h>
12 #include <linux/leds.h>
13 #include <linux/i2c.h>
14 #include <linux/interrupt.h>
15 #include <linux/delay.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/gpio/consumer.h>
19 #include <linux/slab.h>
20 #include <linux/export.h>
21 
22 #include <asm/machdep.h>
23 #include <asm/udbg.h>
24 #include <asm/time.h>
25 #include <asm/uic.h>
26 #include <asm/ppc4xx.h>
27 #include <asm/dma.h>
28 
29 
30 static const struct of_device_id warp_of_bus[] __initconst = {
31 	{ .compatible = "ibm,plb4", },
32 	{ .compatible = "ibm,opb", },
33 	{ .compatible = "ibm,ebc", },
34 	{},
35 };
36 
37 static int __init warp_device_probe(void)
38 {
39 	of_platform_bus_probe(NULL, warp_of_bus, NULL);
40 	return 0;
41 }
42 machine_device_initcall(warp, warp_device_probe);
43 
44 define_machine(warp) {
45 	.name		= "Warp",
46 	.compatible	= "pika,warp",
47 	.progress 	= udbg_progress,
48 	.init_IRQ 	= uic_init_tree,
49 	.get_irq 	= uic_get_irq,
50 	.restart	= ppc4xx_reset_system,
51 	.calibrate_decr = generic_calibrate_decr,
52 };
53 
54 
55 static int __init warp_post_info(void)
56 {
57 	struct device_node *np;
58 	void __iomem *fpga;
59 	u32 post1, post2;
60 
61 	/* Sighhhh... POST information is in the sd area. */
62 	np = of_find_compatible_node(NULL, NULL, "pika,fpga-sd");
63 	if (np == NULL)
64 		return -ENOENT;
65 
66 	fpga = of_iomap(np, 0);
67 	of_node_put(np);
68 	if (fpga == NULL)
69 		return -ENOENT;
70 
71 	post1 = in_be32(fpga + 0x40);
72 	post2 = in_be32(fpga + 0x44);
73 
74 	iounmap(fpga);
75 
76 	if (post1 || post2)
77 		printk(KERN_INFO "Warp POST %08x %08x\n", post1, post2);
78 	else
79 		printk(KERN_INFO "Warp POST OK\n");
80 
81 	return 0;
82 }
83 
84 
85 #ifdef CONFIG_SENSORS_AD7414
86 
87 static LIST_HEAD(dtm_shutdown_list);
88 static void __iomem *dtm_fpga;
89 
90 struct dtm_shutdown {
91 	struct list_head list;
92 	void (*func)(void *arg);
93 	void *arg;
94 };
95 
96 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
97 {
98 	struct dtm_shutdown *shutdown;
99 
100 	shutdown = kmalloc(sizeof(struct dtm_shutdown), GFP_KERNEL);
101 	if (shutdown == NULL)
102 		return -ENOMEM;
103 
104 	shutdown->func = func;
105 	shutdown->arg = arg;
106 
107 	list_add(&shutdown->list, &dtm_shutdown_list);
108 
109 	return 0;
110 }
111 
112 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
113 {
114 	struct dtm_shutdown *shutdown;
115 
116 	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
117 		if (shutdown->func == func && shutdown->arg == arg) {
118 			list_del(&shutdown->list);
119 			kfree(shutdown);
120 			return 0;
121 		}
122 
123 	return -EINVAL;
124 }
125 
126 #define WARP_GREEN_LED	0
127 #define WARP_RED_LED	1
128 
129 static struct gpio_led warp_gpio_led_pins[] = {
130 	[WARP_GREEN_LED] = {
131 		.name		= "green",
132 		.default_state	= LEDS_DEFSTATE_KEEP,
133 		.gpiod		= NULL, /* to be filled by pika_setup_leds() */
134 	},
135 	[WARP_RED_LED] = {
136 		.name		= "red",
137 		.default_state	= LEDS_DEFSTATE_KEEP,
138 		.gpiod		= NULL, /* to be filled by pika_setup_leds() */
139 	},
140 };
141 
142 static struct gpio_led_platform_data warp_gpio_led_data = {
143 	.leds		= warp_gpio_led_pins,
144 	.num_leds	= ARRAY_SIZE(warp_gpio_led_pins),
145 };
146 
147 static struct platform_device warp_gpio_leds = {
148 	.name	= "leds-gpio",
149 	.id	= -1,
150 	.dev	= {
151 		.platform_data = &warp_gpio_led_data,
152 	},
153 };
154 
155 static irqreturn_t temp_isr(int irq, void *context)
156 {
157 	struct dtm_shutdown *shutdown;
158 	int value = 1;
159 
160 	local_irq_disable();
161 
162 	gpiod_set_value(warp_gpio_led_pins[WARP_GREEN_LED].gpiod, 0);
163 
164 	/* Run through the shutdown list. */
165 	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
166 		shutdown->func(shutdown->arg);
167 
168 	printk(KERN_EMERG "\n\nCritical Temperature Shutdown\n\n");
169 
170 	while (1) {
171 		if (dtm_fpga) {
172 			unsigned reset = in_be32(dtm_fpga + 0x14);
173 			out_be32(dtm_fpga + 0x14, reset);
174 		}
175 
176 		gpiod_set_value(warp_gpio_led_pins[WARP_RED_LED].gpiod, value);
177 		value ^= 1;
178 		mdelay(500);
179 	}
180 
181 	/* Not reached */
182 	return IRQ_HANDLED;
183 }
184 
185 /*
186  * Because green and red power LEDs are normally driven by leds-gpio driver,
187  * but in case of critical temperature shutdown we want to drive them
188  * ourselves, we acquire both and then create leds-gpio platform device
189  * ourselves, instead of doing it through device tree. This way we can still
190  * keep access to the gpios and use them when needed.
191  */
192 static int pika_setup_leds(void)
193 {
194 	struct device_node *np, *child;
195 	struct gpio_desc *gpio;
196 	struct gpio_led *led;
197 	int led_count = 0;
198 	int error;
199 	int i;
200 
201 	np = of_find_compatible_node(NULL, NULL, "warp-power-leds");
202 	if (!np) {
203 		printk(KERN_ERR __FILE__ ": Unable to find leds\n");
204 		return -ENOENT;
205 	}
206 
207 	for_each_child_of_node(np, child) {
208 		for (i = 0; i < ARRAY_SIZE(warp_gpio_led_pins); i++) {
209 			led = &warp_gpio_led_pins[i];
210 
211 			if (!of_node_name_eq(child, led->name))
212 				continue;
213 
214 			if (led->gpiod) {
215 				printk(KERN_ERR __FILE__ ": %s led has already been defined\n",
216 				       led->name);
217 				continue;
218 			}
219 
220 			gpio = fwnode_gpiod_get_index(of_fwnode_handle(child),
221 						      NULL, 0, GPIOD_ASIS,
222 						      led->name);
223 			error = PTR_ERR_OR_ZERO(gpio);
224 			if (error) {
225 				printk(KERN_ERR __FILE__ ": Failed to get %s led gpio: %d\n",
226 				       led->name, error);
227 				of_node_put(child);
228 				goto err_cleanup_pins;
229 			}
230 
231 			led->gpiod = gpio;
232 			led_count++;
233 		}
234 	}
235 
236 	of_node_put(np);
237 
238 	/* Skip device registration if no leds have been defined */
239 	if (led_count) {
240 		error = platform_device_register(&warp_gpio_leds);
241 		if (error) {
242 			printk(KERN_ERR __FILE__ ": Unable to add leds-gpio: %d\n",
243 			       error);
244 			goto err_cleanup_pins;
245 		}
246 	}
247 
248 	return 0;
249 
250 err_cleanup_pins:
251 	for (i = 0; i < ARRAY_SIZE(warp_gpio_led_pins); i++) {
252 		led = &warp_gpio_led_pins[i];
253 		gpiod_put(led->gpiod);
254 		led->gpiod = NULL;
255 	}
256 	return error;
257 }
258 
259 static void pika_setup_critical_temp(struct device_node *np,
260 				     struct i2c_client *client)
261 {
262 	int irq, rc;
263 
264 	/* Do this before enabling critical temp interrupt since we
265 	 * may immediately interrupt.
266 	 */
267 	pika_setup_leds();
268 
269 	/* These registers are in 1 degree increments. */
270 	i2c_smbus_write_byte_data(client, 2, 65); /* Thigh */
271 	i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
272 
273 	irq = irq_of_parse_and_map(np, 0);
274 	if (!irq) {
275 		printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
276 		return;
277 	}
278 
279 	rc = request_irq(irq, temp_isr, 0, "ad7414", NULL);
280 	if (rc) {
281 		printk(KERN_ERR __FILE__
282 		       ": Unable to request ad7414 irq %d = %d\n", irq, rc);
283 		return;
284 	}
285 }
286 
287 static inline void pika_dtm_check_fan(void __iomem *fpga)
288 {
289 	static int fan_state;
290 	u32 fan = in_be32(fpga + 0x34) & (1 << 14);
291 
292 	if (fan_state != fan) {
293 		fan_state = fan;
294 		if (fan)
295 			printk(KERN_WARNING "Fan rotation error detected."
296 				   " Please check hardware.\n");
297 	}
298 }
299 
300 static int pika_dtm_thread(void __iomem *fpga)
301 {
302 	struct device_node *np;
303 	struct i2c_client *client;
304 
305 	np = of_find_compatible_node(NULL, NULL, "adi,ad7414");
306 	if (np == NULL)
307 		return -ENOENT;
308 
309 	client = of_find_i2c_device_by_node(np);
310 	if (client == NULL) {
311 		of_node_put(np);
312 		return -ENOENT;
313 	}
314 
315 	pika_setup_critical_temp(np, client);
316 
317 	of_node_put(np);
318 
319 	printk(KERN_INFO "Warp DTM thread running.\n");
320 
321 	while (!kthread_should_stop()) {
322 		int val;
323 
324 		val = i2c_smbus_read_word_data(client, 0);
325 		if (val < 0)
326 			dev_dbg(&client->dev, "DTM read temp failed.\n");
327 		else {
328 			s16 temp = swab16(val);
329 			out_be32(fpga + 0x20, temp);
330 		}
331 
332 		pika_dtm_check_fan(fpga);
333 
334 		set_current_state(TASK_INTERRUPTIBLE);
335 		schedule_timeout(HZ);
336 	}
337 
338 	return 0;
339 }
340 
341 static int __init pika_dtm_start(void)
342 {
343 	struct task_struct *dtm_thread;
344 	struct device_node *np;
345 
346 	np = of_find_compatible_node(NULL, NULL, "pika,fpga");
347 	if (np == NULL)
348 		return -ENOENT;
349 
350 	dtm_fpga = of_iomap(np, 0);
351 	of_node_put(np);
352 	if (dtm_fpga == NULL)
353 		return -ENOENT;
354 
355 	/* Must get post info before thread starts. */
356 	warp_post_info();
357 
358 	dtm_thread = kthread_run(pika_dtm_thread, dtm_fpga, "pika-dtm");
359 	if (IS_ERR(dtm_thread)) {
360 		iounmap(dtm_fpga);
361 		return PTR_ERR(dtm_thread);
362 	}
363 
364 	return 0;
365 }
366 machine_late_initcall(warp, pika_dtm_start);
367 
368 #else /* !CONFIG_SENSORS_AD7414 */
369 
370 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
371 {
372 	return 0;
373 }
374 
375 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
376 {
377 	return 0;
378 }
379 
380 machine_late_initcall(warp, warp_post_info);
381 
382 #endif
383 
384 EXPORT_SYMBOL(pika_dtm_register_shutdown);
385 EXPORT_SYMBOL(pika_dtm_unregister_shutdown);
386