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

   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 };
  52
  53
  54 static int __init warp_post_info(void)
  55 {
  56         struct device_node *np;
  57         void __iomem *fpga;
  58         u32 post1, post2;
  59
  60         /* Sighhhh... POST information is in the sd area. */
  61         np = of_find_compatible_node(NULL, NULL, "pika,fpga-sd");
  62         if (np == NULL)
  63                 return -ENOENT;
  64
  65         fpga = of_iomap(np, 0);
  66         of_node_put(np);
  67         if (fpga == NULL)
  68                 return -ENOENT;
  69
  70         post1 = in_be32(fpga + 0x40);
  71         post2 = in_be32(fpga + 0x44);
  72
  73         iounmap(fpga);
  74
  75         if (post1 || post2)
  76                 printk(KERN_INFO "Warp POST %08x %08x\n", post1, post2);
  77         else
  78                 printk(KERN_INFO "Warp POST OK\n");
  79
  80         return 0;
  81 }
  82
  83
  84 #ifdef CONFIG_SENSORS_AD7414
  85
  86 static void __iomem *dtm_fpga;
  87
  88 #define WARP_GREEN_LED  0
  89 #define WARP_RED_LED    1
  90
  91 static struct gpio_led warp_gpio_led_pins[] = {
  92         [WARP_GREEN_LED] = {
  93                 .name           = "green",
  94                 .default_state  = LEDS_DEFSTATE_KEEP,
  95                 .gpiod          = NULL, /* to be filled by pika_setup_leds() */
  96         },
  97         [WARP_RED_LED] = {
  98                 .name           = "red",
  99                 .default_state  = LEDS_DEFSTATE_KEEP,
 100                 .gpiod          = NULL, /* to be filled by pika_setup_leds() */
 101         },
 102 };
 103
 104 static struct gpio_led_platform_data warp_gpio_led_data = {
 105         .leds           = warp_gpio_led_pins,
 106         .num_leds       = ARRAY_SIZE(warp_gpio_led_pins),
 107 };
 108
 109 static struct platform_device warp_gpio_leds = {
 110         .name   = "leds-gpio",
 111         .id     = -1,
 112         .dev    = {
 113                 .platform_data = &warp_gpio_led_data,
 114         },
 115 };
 116
 117 static irqreturn_t temp_isr(int irq, void *context)
 118 {
 119         int value = 1;
 120
 121         local_irq_disable();
 122
 123         gpiod_set_value(warp_gpio_led_pins[WARP_GREEN_LED].gpiod, 0);
 124
 125         printk(KERN_EMERG "\n\nCritical Temperature Shutdown\n\n");
 126
 127         while (1) {
 128                 if (dtm_fpga) {
 129                         unsigned reset = in_be32(dtm_fpga + 0x14);
 130                         out_be32(dtm_fpga + 0x14, reset);
 131                 }
 132
 133                 gpiod_set_value(warp_gpio_led_pins[WARP_RED_LED].gpiod, value);
 134                 value ^= 1;
 135                 mdelay(500);
 136         }
 137
 138         /* Not reached */
 139         return IRQ_HANDLED;
 140 }
 141
 142 /*
 143  * Because green and red power LEDs are normally driven by leds-gpio driver,
 144  * but in case of critical temperature shutdown we want to drive them
 145  * ourselves, we acquire both and then create leds-gpio platform device
 146  * ourselves, instead of doing it through device tree. This way we can still
 147  * keep access to the gpios and use them when needed.
 148  */
 149 static int pika_setup_leds(void)
 150 {
 151         struct device_node *np, *child;
 152         struct gpio_desc *gpio;
 153         struct gpio_led *led;
 154         int led_count = 0;
 155         int error;
 156         int i;
 157
 158         np = of_find_compatible_node(NULL, NULL, "warp-power-leds");
 159         if (!np) {
 160                 printk(KERN_ERR __FILE__ ": Unable to find leds\n");
 161                 return -ENOENT;
 162         }
 163
 164         for_each_child_of_node(np, child) {
 165                 for (i = 0; i < ARRAY_SIZE(warp_gpio_led_pins); i++) {
 166                         led = &warp_gpio_led_pins[i];
 167
 168                         if (!of_node_name_eq(child, led->name))
 169                                 continue;
 170
 171                         if (led->gpiod) {
 172                                 printk(KERN_ERR __FILE__ ": %s led has already been defined\n",
 173                                        led->name);
 174                                 continue;
 175                         }
 176
 177                         gpio = fwnode_gpiod_get_index(of_fwnode_handle(child),
 178                                                       NULL, 0, GPIOD_ASIS,
 179                                                       led->name);
 180                         error = PTR_ERR_OR_ZERO(gpio);
 181                         if (error) {
 182                                 printk(KERN_ERR __FILE__ ": Failed to get %s led gpio: %d\n",
 183                                        led->name, error);
 184                                 of_node_put(child);
 185                                 goto err_cleanup_pins;
 186                         }
 187
 188                         led->gpiod = gpio;
 189                         led_count++;
 190                 }
 191         }
 192
 193         of_node_put(np);
 194
 195         /* Skip device registration if no leds have been defined */
 196         if (led_count) {
 197                 error = platform_device_register(&warp_gpio_leds);
 198                 if (error) {
 199                         printk(KERN_ERR __FILE__ ": Unable to add leds-gpio: %d\n",
 200                                error);
 201                         goto err_cleanup_pins;
 202                 }
 203         }
 204
 205         return 0;
 206
 207 err_cleanup_pins:
 208         for (i = 0; i < ARRAY_SIZE(warp_gpio_led_pins); i++) {
 209                 led = &warp_gpio_led_pins[i];
 210                 gpiod_put(led->gpiod);
 211                 led->gpiod = NULL;
 212         }
 213         return error;
 214 }
 215
 216 static void pika_setup_critical_temp(struct device_node *np,
 217                                      struct i2c_client *client)
 218 {
 219         int irq, rc;
 220
 221         /* Do this before enabling critical temp interrupt since we
 222          * may immediately interrupt.
 223          */
 224         pika_setup_leds();
 225
 226         /* These registers are in 1 degree increments. */
 227         i2c_smbus_write_byte_data(client, 2, 65); /* Thigh */
 228         i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
 229
 230         irq = irq_of_parse_and_map(np, 0);
 231         if (!irq) {
 232                 printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
 233                 return;
 234         }
 235
 236         rc = request_irq(irq, temp_isr, 0, "ad7414", NULL);
 237         if (rc) {
 238                 printk(KERN_ERR __FILE__
 239                        ": Unable to request ad7414 irq %d = %d\n", irq, rc);
 240                 return;
 241         }
 242 }
 243
 244 static inline void pika_dtm_check_fan(void __iomem *fpga)
 245 {
 246         static int fan_state;
 247         u32 fan = in_be32(fpga + 0x34) & (1 << 14);
 248
 249         if (fan_state != fan) {
 250                 fan_state = fan;
 251                 if (fan)
 252                         printk(KERN_WARNING "Fan rotation error detected."
 253                                    " Please check hardware.\n");
 254         }
 255 }
 256
 257 static int pika_dtm_thread(void __iomem *fpga)
 258 {
 259         struct device_node *np;
 260         struct i2c_client *client;
 261
 262         np = of_find_compatible_node(NULL, NULL, "adi,ad7414");
 263         if (np == NULL)
 264                 return -ENOENT;
 265
 266         client = of_find_i2c_device_by_node(np);
 267         if (client == NULL) {
 268                 of_node_put(np);
 269                 return -ENOENT;
 270         }
 271
 272         pika_setup_critical_temp(np, client);
 273
 274         of_node_put(np);
 275
 276         printk(KERN_INFO "Warp DTM thread running.\n");
 277
 278         while (!kthread_should_stop()) {
 279                 int val;
 280
 281                 val = i2c_smbus_read_word_data(client, 0);
 282                 if (val < 0)
 283                         dev_dbg(&client->dev, "DTM read temp failed.\n");
 284                 else {
 285                         s16 temp = swab16(val);
 286                         out_be32(fpga + 0x20, temp);
 287                 }
 288
 289                 pika_dtm_check_fan(fpga);
 290
 291                 set_current_state(TASK_INTERRUPTIBLE);
 292                 schedule_timeout(HZ);
 293         }
 294
 295         return 0;
 296 }
 297
 298 static int __init pika_dtm_start(void)
 299 {
 300         struct task_struct *dtm_thread;
 301         struct device_node *np;
 302
 303         np = of_find_compatible_node(NULL, NULL, "pika,fpga");
 304         if (np == NULL)
 305                 return -ENOENT;
 306
 307         dtm_fpga = of_iomap(np, 0);
 308         of_node_put(np);
 309         if (dtm_fpga == NULL)
 310                 return -ENOENT;
 311
 312         /* Must get post info before thread starts. */
 313         warp_post_info();
 314
 315         dtm_thread = kthread_run(pika_dtm_thread, dtm_fpga, "pika-dtm");
 316         if (IS_ERR(dtm_thread)) {
 317                 iounmap(dtm_fpga);
 318                 return PTR_ERR(dtm_thread);
 319         }
 320
 321         return 0;
 322 }
 323 machine_late_initcall(warp, pika_dtm_start);
 324
 325 #else /* !CONFIG_SENSORS_AD7414 */
 326
 327 machine_late_initcall(warp, warp_post_info);
 328
 329 #endif