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/platform_device.h>
  12 #include <linux/kthread.h>
  13 #include <linux/leds.h>
  14 #include <linux/i2c.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/delay.h>
  17 #include <linux/of_address.h>
  18 #include <linux/of_irq.h>
  19 #include <linux/gpio/consumer.h>
  20 #include <linux/slab.h>
  21 #include <linux/export.h>
  22
  23 #include <asm/machdep.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 define_machine(warp) {
  46         .name           = "Warp",
  47         .compatible     = "pika,warp",
  48         .progress       = udbg_progress,
  49         .init_IRQ       = uic_init_tree,
  50         .get_irq        = uic_get_irq,
  51         .restart        = ppc4xx_reset_system,
  52 };
  53
  54
  55 static int __init warp_post_info(void)
  56 {
  57         struct device_node *np;
  58         void __iomem *fpga;
  59         u32 post1, post2;
  60
  61         /* Sighhhh... POST information is in the sd area. */
  62         np = of_find_compatible_node(NULL, NULL, "pika,fpga-sd");
  63         if (np == NULL)
  64                 return -ENOENT;
  65
  66         fpga = of_iomap(np, 0);
  67         of_node_put(np);
  68         if (fpga == NULL)
  69                 return -ENOENT;
  70
  71         post1 = in_be32(fpga + 0x40);
  72         post2 = in_be32(fpga + 0x44);
  73
  74         iounmap(fpga);
  75
  76         if (post1 || post2)
  77                 printk(KERN_INFO "Warp POST %08x %08x\n", post1, post2);
  78         else
  79                 printk(KERN_INFO "Warp POST OK\n");
  80
  81         return 0;
  82 }
  83
  84
  85 #ifdef CONFIG_SENSORS_AD7414
  86
  87 static void __iomem *dtm_fpga;
  88
  89 #define WARP_GREEN_LED  0
  90 #define WARP_RED_LED    1
  91
  92 static struct gpio_led warp_gpio_led_pins[] = {
  93         [WARP_GREEN_LED] = {
  94                 .name           = "green",
  95                 .default_state  = LEDS_DEFSTATE_KEEP,
  96                 .gpiod          = NULL, /* to be filled by pika_setup_leds() */
  97         },
  98         [WARP_RED_LED] = {
  99                 .name           = "red",
 100                 .default_state  = LEDS_DEFSTATE_KEEP,
 101                 .gpiod          = NULL, /* to be filled by pika_setup_leds() */
 102         },
 103 };
 104
 105 static struct gpio_led_platform_data warp_gpio_led_data = {
 106         .leds           = warp_gpio_led_pins,
 107         .num_leds       = ARRAY_SIZE(warp_gpio_led_pins),
 108 };
 109
 110 static struct platform_device warp_gpio_leds = {
 111         .name   = "leds-gpio",
 112         .id     = -1,
 113         .dev    = {
 114                 .platform_data = &warp_gpio_led_data,
 115         },
 116 };
 117
 118 static irqreturn_t temp_isr(int irq, void *context)
 119 {
 120         int value = 1;
 121
 122         local_irq_disable();
 123
 124         gpiod_set_value(warp_gpio_led_pins[WARP_GREEN_LED].gpiod, 0);
 125
 126         printk(KERN_EMERG "\n\nCritical Temperature Shutdown\n\n");
 127
 128         while (1) {
 129                 if (dtm_fpga) {
 130                         unsigned reset = in_be32(dtm_fpga + 0x14);
 131                         out_be32(dtm_fpga + 0x14, reset);
 132                 }
 133
 134                 gpiod_set_value(warp_gpio_led_pins[WARP_RED_LED].gpiod, value);
 135                 value ^= 1;
 136                 mdelay(500);
 137         }
 138
 139         /* Not reached */
 140         return IRQ_HANDLED;
 141 }
 142
 143 /*
 144  * Because green and red power LEDs are normally driven by leds-gpio driver,
 145  * but in case of critical temperature shutdown we want to drive them
 146  * ourselves, we acquire both and then create leds-gpio platform device
 147  * ourselves, instead of doing it through device tree. This way we can still
 148  * keep access to the gpios and use them when needed.
 149  */
 150 static int pika_setup_leds(void)
 151 {
 152         struct device_node *np, *child;
 153         struct gpio_desc *gpio;
 154         struct gpio_led *led;
 155         int led_count = 0;
 156         int error;
 157         int i;
 158
 159         np = of_find_compatible_node(NULL, NULL, "warp-power-leds");
 160         if (!np) {
 161                 printk(KERN_ERR __FILE__ ": Unable to find leds\n");
 162                 return -ENOENT;
 163         }
 164
 165         for_each_child_of_node(np, child) {
 166                 for (i = 0; i < ARRAY_SIZE(warp_gpio_led_pins); i++) {
 167                         led = &warp_gpio_led_pins[i];
 168
 169                         if (!of_node_name_eq(child, led->name))
 170                                 continue;
 171
 172                         if (led->gpiod) {
 173                                 printk(KERN_ERR __FILE__ ": %s led has already been defined\n",
 174                                        led->name);
 175                                 continue;
 176                         }
 177
 178                         gpio = fwnode_gpiod_get_index(of_fwnode_handle(child),
 179                                                       NULL, 0, GPIOD_ASIS,
 180                                                       led->name);
 181                         error = PTR_ERR_OR_ZERO(gpio);
 182                         if (error) {
 183                                 printk(KERN_ERR __FILE__ ": Failed to get %s led gpio: %d\n",
 184                                        led->name, error);
 185                                 of_node_put(child);
 186                                 goto err_cleanup_pins;
 187                         }
 188
 189                         led->gpiod = gpio;
 190                         led_count++;
 191                 }
 192         }
 193
 194         of_node_put(np);
 195
 196         /* Skip device registration if no leds have been defined */
 197         if (led_count) {
 198                 error = platform_device_register(&warp_gpio_leds);
 199                 if (error) {
 200                         printk(KERN_ERR __FILE__ ": Unable to add leds-gpio: %d\n",
 201                                error);
 202                         goto err_cleanup_pins;
 203                 }
 204         }
 205
 206         return 0;
 207
 208 err_cleanup_pins:
 209         for (i = 0; i < ARRAY_SIZE(warp_gpio_led_pins); i++) {
 210                 led = &warp_gpio_led_pins[i];
 211                 gpiod_put(led->gpiod);
 212                 led->gpiod = NULL;
 213         }
 214         return error;
 215 }
 216
 217 static void pika_setup_critical_temp(struct device_node *np,
 218                                      struct i2c_client *client)
 219 {
 220         int irq, rc;
 221
 222         /* Do this before enabling critical temp interrupt since we
 223          * may immediately interrupt.
 224          */
 225         pika_setup_leds();
 226
 227         /* These registers are in 1 degree increments. */
 228         i2c_smbus_write_byte_data(client, 2, 65); /* Thigh */
 229         i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
 230
 231         irq = irq_of_parse_and_map(np, 0);
 232         if (!irq) {
 233                 printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
 234                 return;
 235         }
 236
 237         rc = request_irq(irq, temp_isr, 0, "ad7414", NULL);
 238         if (rc) {
 239                 printk(KERN_ERR __FILE__
 240                        ": Unable to request ad7414 irq %d = %d\n", irq, rc);
 241                 return;
 242         }
 243 }
 244
 245 static inline void pika_dtm_check_fan(void __iomem *fpga)
 246 {
 247         static int fan_state;
 248         u32 fan = in_be32(fpga + 0x34) & (1 << 14);
 249
 250         if (fan_state != fan) {
 251                 fan_state = fan;
 252                 if (fan)
 253                         printk(KERN_WARNING "Fan rotation error detected."
 254                                    " Please check hardware.\n");
 255         }
 256 }
 257
 258 static int pika_dtm_thread(void __iomem *fpga)
 259 {
 260         struct device_node *np;
 261         struct i2c_client *client;
 262
 263         np = of_find_compatible_node(NULL, NULL, "adi,ad7414");
 264         if (np == NULL)
 265                 return -ENOENT;
 266
 267         client = of_find_i2c_device_by_node(np);
 268         if (client == NULL) {
 269                 of_node_put(np);
 270                 return -ENOENT;
 271         }
 272
 273         pika_setup_critical_temp(np, client);
 274
 275         of_node_put(np);
 276
 277         printk(KERN_INFO "Warp DTM thread running.\n");
 278
 279         while (!kthread_should_stop()) {
 280                 int val;
 281
 282                 val = i2c_smbus_read_word_data(client, 0);
 283                 if (val < 0)
 284                         dev_dbg(&client->dev, "DTM read temp failed.\n");
 285                 else {
 286                         s16 temp = swab16(val);
 287                         out_be32(fpga + 0x20, temp);
 288                 }
 289
 290                 pika_dtm_check_fan(fpga);
 291
 292                 set_current_state(TASK_INTERRUPTIBLE);
 293                 schedule_timeout(HZ);
 294         }
 295
 296         return 0;
 297 }
 298
 299 static int __init pika_dtm_start(void)
 300 {
 301         struct task_struct *dtm_thread;
 302         struct device_node *np;
 303
 304         np = of_find_compatible_node(NULL, NULL, "pika,fpga");
 305         if (np == NULL)
 306                 return -ENOENT;
 307
 308         dtm_fpga = of_iomap(np, 0);
 309         of_node_put(np);
 310         if (dtm_fpga == NULL)
 311                 return -ENOENT;
 312
 313         /* Must get post info before thread starts. */
 314         warp_post_info();
 315
 316         dtm_thread = kthread_run(pika_dtm_thread, dtm_fpga, "pika-dtm");
 317         if (IS_ERR(dtm_thread)) {
 318                 iounmap(dtm_fpga);
 319                 return PTR_ERR(dtm_thread);
 320         }
 321
 322         return 0;
 323 }
 324 machine_late_initcall(warp, pika_dtm_start);
 325
 326 #else /* !CONFIG_SENSORS_AD7414 */
 327
 328 machine_late_initcall(warp, warp_post_info);
 329
 330 #endif