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/init.h>
9 #include <linux/of_platform.h>
10 #include <linux/kthread.h>
11 #include <linux/i2c.h>
12 #include <linux/interrupt.h>
13 #include <linux/delay.h>
14 #include <linux/of_gpio.h>
15 #include <linux/slab.h>
16 #include <linux/export.h>
17 
18 #include <asm/machdep.h>
19 #include <asm/prom.h>
20 #include <asm/udbg.h>
21 #include <asm/time.h>
22 #include <asm/uic.h>
23 #include <asm/ppc4xx.h>
24 #include <asm/dma.h>
25 
26 
27 static const struct of_device_id warp_of_bus[] __initconst = {
28 	{ .compatible = "ibm,plb4", },
29 	{ .compatible = "ibm,opb", },
30 	{ .compatible = "ibm,ebc", },
31 	{},
32 };
33 
warp_device_probe(void)34 static int __init warp_device_probe(void)
35 {
36 	of_platform_bus_probe(NULL, warp_of_bus, NULL);
37 	return 0;
38 }
39 machine_device_initcall(warp, warp_device_probe);
40 
warp_probe(void)41 static int __init warp_probe(void)
42 {
43 	if (!of_machine_is_compatible("pika,warp"))
44 		return 0;
45 
46 	return 1;
47 }
48 
define_machine(warp)49 define_machine(warp) {
50 	.name		= "Warp",
51 	.probe 		= warp_probe,
52 	.progress 	= udbg_progress,
53 	.init_IRQ 	= uic_init_tree,
54 	.get_irq 	= uic_get_irq,
55 	.restart	= ppc4xx_reset_system,
56 	.calibrate_decr = generic_calibrate_decr,
57 };
58 
59 
warp_post_info(void)60 static int __init warp_post_info(void)
61 {
62 	struct device_node *np;
63 	void __iomem *fpga;
64 	u32 post1, post2;
65 
66 	/* Sighhhh... POST information is in the sd area. */
67 	np = of_find_compatible_node(NULL, NULL, "pika,fpga-sd");
68 	if (np == NULL)
69 		return -ENOENT;
70 
71 	fpga = of_iomap(np, 0);
72 	of_node_put(np);
73 	if (fpga == NULL)
74 		return -ENOENT;
75 
76 	post1 = in_be32(fpga + 0x40);
77 	post2 = in_be32(fpga + 0x44);
78 
79 	iounmap(fpga);
80 
81 	if (post1 || post2)
82 		printk(KERN_INFO "Warp POST %08x %08x\n", post1, post2);
83 	else
84 		printk(KERN_INFO "Warp POST OK\n");
85 
86 	return 0;
87 }
88 
89 
90 #ifdef CONFIG_SENSORS_AD7414
91 
92 static LIST_HEAD(dtm_shutdown_list);
93 static void __iomem *dtm_fpga;
94 static unsigned green_led, red_led;
95 
96 
97 struct dtm_shutdown {
98 	struct list_head list;
99 	void (*func)(void *arg);
100 	void *arg;
101 };
102 
103 
pika_dtm_register_shutdown(void (* func)(void * arg),void * arg)104 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
105 {
106 	struct dtm_shutdown *shutdown;
107 
108 	shutdown = kmalloc(sizeof(struct dtm_shutdown), GFP_KERNEL);
109 	if (shutdown == NULL)
110 		return -ENOMEM;
111 
112 	shutdown->func = func;
113 	shutdown->arg = arg;
114 
115 	list_add(&shutdown->list, &dtm_shutdown_list);
116 
117 	return 0;
118 }
119 
pika_dtm_unregister_shutdown(void (* func)(void * arg),void * arg)120 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
121 {
122 	struct dtm_shutdown *shutdown;
123 
124 	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
125 		if (shutdown->func == func && shutdown->arg == arg) {
126 			list_del(&shutdown->list);
127 			kfree(shutdown);
128 			return 0;
129 		}
130 
131 	return -EINVAL;
132 }
133 
temp_isr(int irq,void * context)134 static irqreturn_t temp_isr(int irq, void *context)
135 {
136 	struct dtm_shutdown *shutdown;
137 	int value = 1;
138 
139 	local_irq_disable();
140 
141 	gpio_set_value(green_led, 0);
142 
143 	/* Run through the shutdown list. */
144 	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
145 		shutdown->func(shutdown->arg);
146 
147 	printk(KERN_EMERG "\n\nCritical Temperature Shutdown\n\n");
148 
149 	while (1) {
150 		if (dtm_fpga) {
151 			unsigned reset = in_be32(dtm_fpga + 0x14);
152 			out_be32(dtm_fpga + 0x14, reset);
153 		}
154 
155 		gpio_set_value(red_led, value);
156 		value ^= 1;
157 		mdelay(500);
158 	}
159 
160 	/* Not reached */
161 	return IRQ_HANDLED;
162 }
163 
pika_setup_leds(void)164 static int pika_setup_leds(void)
165 {
166 	struct device_node *np, *child;
167 
168 	np = of_find_compatible_node(NULL, NULL, "gpio-leds");
169 	if (!np) {
170 		printk(KERN_ERR __FILE__ ": Unable to find leds\n");
171 		return -ENOENT;
172 	}
173 
174 	for_each_child_of_node(np, child)
175 		if (of_node_name_eq(child, "green"))
176 			green_led = of_get_gpio(child, 0);
177 		else if (of_node_name_eq(child, "red"))
178 			red_led = of_get_gpio(child, 0);
179 
180 	of_node_put(np);
181 
182 	return 0;
183 }
184 
pika_setup_critical_temp(struct device_node * np,struct i2c_client * client)185 static void pika_setup_critical_temp(struct device_node *np,
186 				     struct i2c_client *client)
187 {
188 	int irq, rc;
189 
190 	/* Do this before enabling critical temp interrupt since we
191 	 * may immediately interrupt.
192 	 */
193 	pika_setup_leds();
194 
195 	/* These registers are in 1 degree increments. */
196 	i2c_smbus_write_byte_data(client, 2, 65); /* Thigh */
197 	i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
198 
199 	irq = irq_of_parse_and_map(np, 0);
200 	if (!irq) {
201 		printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
202 		return;
203 	}
204 
205 	rc = request_irq(irq, temp_isr, 0, "ad7414", NULL);
206 	if (rc) {
207 		printk(KERN_ERR __FILE__
208 		       ": Unable to request ad7414 irq %d = %d\n", irq, rc);
209 		return;
210 	}
211 }
212 
pika_dtm_check_fan(void __iomem * fpga)213 static inline void pika_dtm_check_fan(void __iomem *fpga)
214 {
215 	static int fan_state;
216 	u32 fan = in_be32(fpga + 0x34) & (1 << 14);
217 
218 	if (fan_state != fan) {
219 		fan_state = fan;
220 		if (fan)
221 			printk(KERN_WARNING "Fan rotation error detected."
222 				   " Please check hardware.\n");
223 	}
224 }
225 
pika_dtm_thread(void __iomem * fpga)226 static int pika_dtm_thread(void __iomem *fpga)
227 {
228 	struct device_node *np;
229 	struct i2c_client *client;
230 
231 	np = of_find_compatible_node(NULL, NULL, "adi,ad7414");
232 	if (np == NULL)
233 		return -ENOENT;
234 
235 	client = of_find_i2c_device_by_node(np);
236 	if (client == NULL) {
237 		of_node_put(np);
238 		return -ENOENT;
239 	}
240 
241 	pika_setup_critical_temp(np, client);
242 
243 	of_node_put(np);
244 
245 	printk(KERN_INFO "Warp DTM thread running.\n");
246 
247 	while (!kthread_should_stop()) {
248 		int val;
249 
250 		val = i2c_smbus_read_word_data(client, 0);
251 		if (val < 0)
252 			dev_dbg(&client->dev, "DTM read temp failed.\n");
253 		else {
254 			s16 temp = swab16(val);
255 			out_be32(fpga + 0x20, temp);
256 		}
257 
258 		pika_dtm_check_fan(fpga);
259 
260 		set_current_state(TASK_INTERRUPTIBLE);
261 		schedule_timeout(HZ);
262 	}
263 
264 	return 0;
265 }
266 
pika_dtm_start(void)267 static int __init pika_dtm_start(void)
268 {
269 	struct task_struct *dtm_thread;
270 	struct device_node *np;
271 
272 	np = of_find_compatible_node(NULL, NULL, "pika,fpga");
273 	if (np == NULL)
274 		return -ENOENT;
275 
276 	dtm_fpga = of_iomap(np, 0);
277 	of_node_put(np);
278 	if (dtm_fpga == NULL)
279 		return -ENOENT;
280 
281 	/* Must get post info before thread starts. */
282 	warp_post_info();
283 
284 	dtm_thread = kthread_run(pika_dtm_thread, dtm_fpga, "pika-dtm");
285 	if (IS_ERR(dtm_thread)) {
286 		iounmap(dtm_fpga);
287 		return PTR_ERR(dtm_thread);
288 	}
289 
290 	return 0;
291 }
292 machine_late_initcall(warp, pika_dtm_start);
293 
294 #else /* !CONFIG_SENSORS_AD7414 */
295 
pika_dtm_register_shutdown(void (* func)(void * arg),void * arg)296 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
297 {
298 	return 0;
299 }
300 
pika_dtm_unregister_shutdown(void (* func)(void * arg),void * arg)301 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
302 {
303 	return 0;
304 }
305 
306 machine_late_initcall(warp, warp_post_info);
307 
308 #endif
309 
310 EXPORT_SYMBOL(pika_dtm_register_shutdown);
311 EXPORT_SYMBOL(pika_dtm_unregister_shutdown);
312