kernel/arch/powerpc/platforms/44x/warp.c

   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
  31 static const struct of_device_id warp_of_bus[] __initconst = {
  32         { .compatible = "ibm,plb4", },
  33         { .compatible = "ibm,opb", },
  34         { .compatible = "ibm,ebc", },
  35         {},
  36 };
  37
  38 static int __init warp_device_probe(void)
  39 {
  40         of_platform_bus_probe(NULL, warp_of_bus, NULL);
  41         return 0;
  42 }
  43 machine_device_initcall(warp, warp_device_probe);
  44
  45 static 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
  58 define_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
  69 static 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
 101 static LIST_HEAD(dtm_shutdown_list);
 102 static void __iomem *dtm_fpga;
 103 static unsigned green_led, red_led;
 104
 105
 106 struct dtm_shutdown {
 107         struct list_head list;
 108         void (*func)(void *arg);
 109         void *arg;
 110 };
 111
 112
 113 int 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
 129 int 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
 143 static 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
 173 static 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
 194 static 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
 222 static 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
 235 static 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
 276 static 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 }
 301 machine_late_initcall(warp, pika_dtm_start);
 302
 303 #else /* !CONFIG_SENSORS_AD7414 */
 304
 305 int pika_dtm_register_shutdown(void (*func)(void *arg), void *arg)
 306 {
 307         return 0;
 308 }
 309
 310 int pika_dtm_unregister_shutdown(void (*func)(void *arg), void *arg)
 311 {
 312         return 0;
 313 }
 314
 315 machine_late_initcall(warp, warp_post_info);
 316
 317 #endif
 318
 319 EXPORT_SYMBOL(pika_dtm_register_shutdown);
 320 EXPORT_SYMBOL(pika_dtm_unregister_shutdown);