drivers/sysreset/sysreset-uclass.c

   1 /*
   2  * Copyright (C) 2015 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <sysreset.h>
  10 #include <dm.h>
  11 #include <errno.h>
  12 #include <regmap.h>
  13 #include <dm/device-internal.h>
  14 #include <dm/lists.h>
  15 #include <dm/root.h>
  16 #include <linux/err.h>
  17
  18 int sysreset_request(struct udevice *dev, enum sysreset_t type)
  19 {
  20         struct sysreset_ops *ops = sysreset_get_ops(dev);
  21
  22         if (!ops->request)
  23                 return -ENOSYS;
  24
  25         return ops->request(dev, type);
  26 }
  27
  28 int sysreset_walk(enum sysreset_t type)
  29 {
  30         struct udevice *dev;
  31         int ret = -ENOSYS;
  32
  33         while (ret != -EINPROGRESS && type < SYSRESET_COUNT) {
  34                 for (uclass_first_device(UCLASS_SYSRESET, &dev);
  35                      dev;
  36                      uclass_next_device(&dev)) {
  37                         ret = sysreset_request(dev, type);
  38                         if (ret == -EINPROGRESS)
  39                                 break;
  40                 }
  41                 type++;
  42         }
  43
  44         return ret;
  45 }
  46
  47 void sysreset_walk_halt(enum sysreset_t type)
  48 {
  49         int ret;
  50
  51         ret = sysreset_walk(type);
  52
  53         /* Wait for the reset to take effect */
  54         if (ret == -EINPROGRESS)
  55                 mdelay(100);
  56
  57         /* Still no reset? Give up */
  58         debug("System reset not supported on this platform\n");
  59         hang();
  60 }
  61
  62 /**
  63  * reset_cpu() - calls sysreset_walk(SYSRESET_WARM)
  64  */
  65 void reset_cpu(ulong addr)
  66 {
  67         sysreset_walk_halt(SYSRESET_WARM);
  68 }
  69
  70
  71 int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  72 {
  73         sysreset_walk_halt(SYSRESET_WARM);
  74
  75         return 0;
  76 }
  77
  78 UCLASS_DRIVER(sysreset) = {
  79         .id             = UCLASS_SYSRESET,
  80         .name           = "sysreset",
  81 };