xref: /openbmc/linux/arch/powerpc/platforms/44x/warp.c (revision fb8d6c8d) 
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 
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 
41 static int __init warp_probe(void)
42 {
43 	if (!of_machine_is_compatible("pika,warp"))
44 		return 0;
45 
46 	/* For arch_dma_alloc */
47 	ISA_DMA_THRESHOLD = ~0L;
48 
49 	return 1;
50 }
51 
52 define_machine(warp) {
53 	.name		= "Warp",
54 	.probe 		= warp_probe,
55 	.progress 	= udbg_progress,
56 	.init_IRQ 	= uic_init_tree,
57 	.get_irq 	= uic_get_irq,
58 	.restart	= ppc4xx_reset_system,
59 	.calibrate_decr = generic_calibrate_decr,
60 };
61 
62 
63 static int __init warp_post_info(void)
64 {
65 	struct device_node *np;
66 	void __iomem *fpga;
67 	u32 post1, post2;
68 
69 	/* Sighhhh... POST information is in the sd area. */
70 	np = of_find_compatible_node(NULL, NULL, "pika,fpga-sd");
71 	if (np == NULL)
72 		return -ENOENT;
73 
74 	fpga = of_iomap(np, 0);
75 	of_node_put(np);
76 	if (fpga == NULL)
77 		return -ENOENT;
78 
79 	post1 = in_be32(fpga + 0x40);
80 	post2 = in_be32(fpga + 0x44);
81 
82 	iounmap(fpga);
83 
84 	if (post1 || post2)
85 		printk(KERN_INFO "Warp POST %08x %08x\n", post1, post2);
86 	else
87 		printk(KERN_INFO "Warp POST OK\n");
88 
89 	return 0;
90 }
91 
92 
93 #ifdef CONFIG_SENSORS_AD7414
94 
95 static LIST_HEAD(dtm_shutdown_list);
96 static void __iomem *dtm_fpga;
97 static unsigned green_led, red_led;
98 
99 
100 struct dtm_shutdown {
101 	struct list_head list;
102 	void (*func)(void *arg);
103 	void *arg;
104 };
105 
106 
107 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
108 {
109 	struct dtm_shutdown *shutdown;
110 
111 	shutdown = kmalloc(sizeof(struct dtm_shutdown), GFP_KERNEL);
112 	if (shutdown == NULL)
113 		return -ENOMEM;
114 
115 	shutdown->func = func;
116 	shutdown->arg = arg;
117 
118 	list_add(&shutdown->list, &dtm_shutdown_list);
119 
120 	return 0;
121 }
122 
123 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
124 {
125 	struct dtm_shutdown *shutdown;
126 
127 	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
128 		if (shutdown->func == func && shutdown->arg == arg) {
129 			list_del(&shutdown->list);
130 			kfree(shutdown);
131 			return 0;
132 		}
133 
134 	return -EINVAL;
135 }
136 
137 static irqreturn_t temp_isr(int irq, void *context)
138 {
139 	struct dtm_shutdown *shutdown;
140 	int value = 1;
141 
142 	local_irq_disable();
143 
144 	gpio_set_value(green_led, 0);
145 
146 	/* Run through the shutdown list. */
147 	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
148 		shutdown->func(shutdown->arg);
149 
150 	printk(KERN_EMERG "\n\nCritical Temperature Shutdown\n\n");
151 
152 	while (1) {
153 		if (dtm_fpga) {
154 			unsigned reset = in_be32(dtm_fpga + 0x14);
155 			out_be32(dtm_fpga + 0x14, reset);
156 		}
157 
158 		gpio_set_value(red_led, value);
159 		value ^= 1;
160 		mdelay(500);
161 	}
162 
163 	/* Not reached */
164 	return IRQ_HANDLED;
165 }
166 
167 static int pika_setup_leds(void)
168 {
169 	struct device_node *np, *child;
170 
171 	np = of_find_compatible_node(NULL, NULL, "gpio-leds");
172 	if (!np) {
173 		printk(KERN_ERR __FILE__ ": Unable to find leds\n");
174 		return -ENOENT;
175 	}
176 
177 	for_each_child_of_node(np, child)
178 		if (of_node_name_eq(child, "green"))
179 			green_led = of_get_gpio(child, 0);
180 		else if (of_node_name_eq(child, "red"))
181 			red_led = of_get_gpio(child, 0);
182 
183 	of_node_put(np);
184 
185 	return 0;
186 }
187 
188 static void pika_setup_critical_temp(struct device_node *np,
189 				     struct i2c_client *client)
190 {
191 	int irq, rc;
192 
193 	/* Do this before enabling critical temp interrupt since we
194 	 * may immediately interrupt.
195 	 */
196 	pika_setup_leds();
197 
198 	/* These registers are in 1 degree increments. */
199 	i2c_smbus_write_byte_data(client, 2, 65); /* Thigh */
200 	i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
201 
202 	irq = irq_of_parse_and_map(np, 0);
203 	if (!irq) {
204 		printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
205 		return;
206 	}
207 
208 	rc = request_irq(irq, temp_isr, 0, "ad7414", NULL);
209 	if (rc) {
210 		printk(KERN_ERR __FILE__
211 		       ": Unable to request ad7414 irq %d = %d\n", irq, rc);
212 		return;
213 	}
214 }
215 
216 static inline void pika_dtm_check_fan(void __iomem *fpga)
217 {
218 	static int fan_state;
219 	u32 fan = in_be32(fpga + 0x34) & (1 << 14);
220 
221 	if (fan_state != fan) {
222 		fan_state = fan;
223 		if (fan)
224 			printk(KERN_WARNING "Fan rotation error detected."
225 				   " Please check hardware.\n");
226 	}
227 }
228 
229 static int pika_dtm_thread(void __iomem *fpga)
230 {
231 	struct device_node *np;
232 	struct i2c_client *client;
233 
234 	np = of_find_compatible_node(NULL, NULL, "adi,ad7414");
235 	if (np == NULL)
236 		return -ENOENT;
237 
238 	client = of_find_i2c_device_by_node(np);
239 	if (client == NULL) {
240 		of_node_put(np);
241 		return -ENOENT;
242 	}
243 
244 	pika_setup_critical_temp(np, client);
245 
246 	of_node_put(np);
247 
248 	printk(KERN_INFO "Warp DTM thread running.\n");
249 
250 	while (!kthread_should_stop()) {
251 		int val;
252 
253 		val = i2c_smbus_read_word_data(client, 0);
254 		if (val < 0)
255 			dev_dbg(&client->dev, "DTM read temp failed.\n");
256 		else {
257 			s16 temp = swab16(val);
258 			out_be32(fpga + 0x20, temp);
259 		}
260 
261 		pika_dtm_check_fan(fpga);
262 
263 		set_current_state(TASK_INTERRUPTIBLE);
264 		schedule_timeout(HZ);
265 	}
266 
267 	return 0;
268 }
269 
270 static int __init pika_dtm_start(void)
271 {
272 	struct task_struct *dtm_thread;
273 	struct device_node *np;
274 
275 	np = of_find_compatible_node(NULL, NULL, "pika,fpga");
276 	if (np == NULL)
277 		return -ENOENT;
278 
279 	dtm_fpga = of_iomap(np, 0);
280 	of_node_put(np);
281 	if (dtm_fpga == NULL)
282 		return -ENOENT;
283 
284 	/* Must get post info before thread starts. */
285 	warp_post_info();
286 
287 	dtm_thread = kthread_run(pika_dtm_thread, dtm_fpga, "pika-dtm");
288 	if (IS_ERR(dtm_thread)) {
289 		iounmap(dtm_fpga);
290 		return PTR_ERR(dtm_thread);
291 	}
292 
293 	return 0;
294 }
295 machine_late_initcall(warp, pika_dtm_start);
296 
297 #else /* !CONFIG_SENSORS_AD7414 */
298 
299 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
300 {
301 	return 0;
302 }
303 
304 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
305 {
306 	return 0;
307 }
308 
309 machine_late_initcall(warp, warp_post_info);
310 
311 #endif
312 
313 EXPORT_SYMBOL(pika_dtm_register_shutdown);
314 EXPORT_SYMBOL(pika_dtm_unregister_shutdown);
315