1/*
2 * PIKA Warp(tm) board specific routines
3 *
4 * Copyright (c) 2008-2009 PIKA Technologies
5 *   Sean MacLennan <smaclennan@pikatech.com>
6 *
7 * This program is free software; you can redistribute  it and/or modify it
8 * under  the terms of  the GNU General  Public License as published by the
9 * Free Software Foundation;  either version 2 of the  License, or (at your
10 * option) any later version.
11 */
12#include <linux/init.h>
13#include <linux/of_platform.h>
14#include <linux/kthread.h>
15#include <linux/i2c.h>
16#include <linux/interrupt.h>
17#include <linux/delay.h>
18#include <linux/of_gpio.h>
19#include <linux/slab.h>
20#include <linux/export.h>
21
22#include <asm/machdep.h>
23#include <asm/prom.h>
24#include <asm/udbg.h>
25#include <asm/time.h>
26#include <asm/uic.h>
27#include <asm/ppc4xx.h>
28#include <asm/dma.h>
29
30
31static const struct of_device_id warp_of_bus[] __initconst = {
32	{ .compatible = "ibm,plb4", },
33	{ .compatible = "ibm,opb", },
34	{ .compatible = "ibm,ebc", },
35	{},
36};
37
38static int __init warp_device_probe(void)
39{
40	of_platform_bus_probe(NULL, warp_of_bus, NULL);
41	return 0;
42}
43machine_device_initcall(warp, warp_device_probe);
44
45static int __init warp_probe(void)
46{
47	unsigned long root = of_get_flat_dt_root();
48
49	if (!of_flat_dt_is_compatible(root, "pika,warp"))
50		return 0;
51
52	/* For __dma_alloc_coherent */
53	ISA_DMA_THRESHOLD = ~0L;
54
55	return 1;
56}
57
58define_machine(warp) {
59	.name		= "Warp",
60	.probe 		= warp_probe,
61	.progress 	= udbg_progress,
62	.init_IRQ 	= uic_init_tree,
63	.get_irq 	= uic_get_irq,
64	.restart	= ppc4xx_reset_system,
65	.calibrate_decr = generic_calibrate_decr,
66};
67
68
69static int __init warp_post_info(void)
70{
71	struct device_node *np;
72	void __iomem *fpga;
73	u32 post1, post2;
74
75	/* Sighhhh... POST information is in the sd area. */
76	np = of_find_compatible_node(NULL, NULL, "pika,fpga-sd");
77	if (np == NULL)
78		return -ENOENT;
79
80	fpga = of_iomap(np, 0);
81	of_node_put(np);
82	if (fpga == NULL)
83		return -ENOENT;
84
85	post1 = in_be32(fpga + 0x40);
86	post2 = in_be32(fpga + 0x44);
87
88	iounmap(fpga);
89
90	if (post1 || post2)
91		printk(KERN_INFO "Warp POST %08x %08x\n", post1, post2);
92	else
93		printk(KERN_INFO "Warp POST OK\n");
94
95	return 0;
96}
97
98
99#ifdef CONFIG_SENSORS_AD7414
100
101static LIST_HEAD(dtm_shutdown_list);
102static void __iomem *dtm_fpga;
103static unsigned green_led, red_led;
104
105
106struct dtm_shutdown {
107	struct list_head list;
108	void (*func)(void *arg);
109	void *arg;
110};
111
112
113int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
114{
115	struct dtm_shutdown *shutdown;
116
117	shutdown = kmalloc(sizeof(struct dtm_shutdown), GFP_KERNEL);
118	if (shutdown == NULL)
119		return -ENOMEM;
120
121	shutdown->func = func;
122	shutdown->arg = arg;
123
124	list_add(&shutdown->list, &dtm_shutdown_list);
125
126	return 0;
127}
128
129int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
130{
131	struct dtm_shutdown *shutdown;
132
133	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
134		if (shutdown->func == func && shutdown->arg == arg) {
135			list_del(&shutdown->list);
136			kfree(shutdown);
137			return 0;
138		}
139
140	return -EINVAL;
141}
142
143static irqreturn_t temp_isr(int irq, void *context)
144{
145	struct dtm_shutdown *shutdown;
146	int value = 1;
147
148	local_irq_disable();
149
150	gpio_set_value(green_led, 0);
151
152	/* Run through the shutdown list. */
153	list_for_each_entry(shutdown, &dtm_shutdown_list, list)
154		shutdown->func(shutdown->arg);
155
156	printk(KERN_EMERG "\n\nCritical Temperature Shutdown\n\n");
157
158	while (1) {
159		if (dtm_fpga) {
160			unsigned reset = in_be32(dtm_fpga + 0x14);
161			out_be32(dtm_fpga + 0x14, reset);
162		}
163
164		gpio_set_value(red_led, value);
165		value ^= 1;
166		mdelay(500);
167	}
168
169	/* Not reached */
170	return IRQ_HANDLED;
171}
172
173static int pika_setup_leds(void)
174{
175	struct device_node *np, *child;
176
177	np = of_find_compatible_node(NULL, NULL, "gpio-leds");
178	if (!np) {
179		printk(KERN_ERR __FILE__ ": Unable to find leds\n");
180		return -ENOENT;
181	}
182
183	for_each_child_of_node(np, child)
184		if (strcmp(child->name, "green") == 0)
185			green_led = of_get_gpio(child, 0);
186		else if (strcmp(child->name, "red") == 0)
187			red_led = of_get_gpio(child, 0);
188
189	of_node_put(np);
190
191	return 0;
192}
193
194static void pika_setup_critical_temp(struct device_node *np,
195				     struct i2c_client *client)
196{
197	int irq, rc;
198
199	/* Do this before enabling critical temp interrupt since we
200	 * may immediately interrupt.
201	 */
202	pika_setup_leds();
203
204	/* These registers are in 1 degree increments. */
205	i2c_smbus_write_byte_data(client, 2, 65); /* Thigh */
206	i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
207
208	irq = irq_of_parse_and_map(np, 0);
209	if (irq  == NO_IRQ) {
210		printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
211		return;
212	}
213
214	rc = request_irq(irq, temp_isr, 0, "ad7414", NULL);
215	if (rc) {
216		printk(KERN_ERR __FILE__
217		       ": Unable to request ad7414 irq %d = %d\n", irq, rc);
218		return;
219	}
220}
221
222static inline void pika_dtm_check_fan(void __iomem *fpga)
223{
224	static int fan_state;
225	u32 fan = in_be32(fpga + 0x34) & (1 << 14);
226
227	if (fan_state != fan) {
228		fan_state = fan;
229		if (fan)
230			printk(KERN_WARNING "Fan rotation error detected."
231				   " Please check hardware.\n");
232	}
233}
234
235static int pika_dtm_thread(void __iomem *fpga)
236{
237	struct device_node *np;
238	struct i2c_client *client;
239
240	np = of_find_compatible_node(NULL, NULL, "adi,ad7414");
241	if (np == NULL)
242		return -ENOENT;
243
244	client = of_find_i2c_device_by_node(np);
245	if (client == NULL) {
246		of_node_put(np);
247		return -ENOENT;
248	}
249
250	pika_setup_critical_temp(np, client);
251
252	of_node_put(np);
253
254	printk(KERN_INFO "Warp DTM thread running.\n");
255
256	while (!kthread_should_stop()) {
257		int val;
258
259		val = i2c_smbus_read_word_data(client, 0);
260		if (val < 0)
261			dev_dbg(&client->dev, "DTM read temp failed.\n");
262		else {
263			s16 temp = swab16(val);
264			out_be32(fpga + 0x20, temp);
265		}
266
267		pika_dtm_check_fan(fpga);
268
269		set_current_state(TASK_INTERRUPTIBLE);
270		schedule_timeout(HZ);
271	}
272
273	return 0;
274}
275
276static int __init pika_dtm_start(void)
277{
278	struct task_struct *dtm_thread;
279	struct device_node *np;
280
281	np = of_find_compatible_node(NULL, NULL, "pika,fpga");
282	if (np == NULL)
283		return -ENOENT;
284
285	dtm_fpga = of_iomap(np, 0);
286	of_node_put(np);
287	if (dtm_fpga == NULL)
288		return -ENOENT;
289
290	/* Must get post info before thread starts. */
291	warp_post_info();
292
293	dtm_thread = kthread_run(pika_dtm_thread, dtm_fpga, "pika-dtm");
294	if (IS_ERR(dtm_thread)) {
295		iounmap(dtm_fpga);
296		return PTR_ERR(dtm_thread);
297	}
298
299	return 0;
300}
301machine_late_initcall(warp, pika_dtm_start);
302
303#else /* !CONFIG_SENSORS_AD7414 */
304
305int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
306{
307	return 0;
308}
309
310int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
311{
312	return 0;
313}
314
315machine_late_initcall(warp, warp_post_info);
316
317#endif
318
319EXPORT_SYMBOL(pika_dtm_register_shutdown);
320EXPORT_SYMBOL(pika_dtm_unregister_shutdown);
321