arch/xtensa/platforms/iss/setup.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *
   4  * arch/xtensa/platform-iss/setup.c
   5  *
   6  * Platform specific initialization.
   7  *
   8  * Authors: Chris Zankel <chris@zankel.net>
   9  *          Joe Taylor <joe@tensilica.com>
  10  *
  11  * Copyright 2001 - 2005 Tensilica Inc.
  12  * Copyright 2017 Cadence Design Systems Inc.
  13  */
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/notifier.h>
  17 #include <linux/panic_notifier.h>
  18 #include <linux/printk.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21
  22 #include <asm/platform.h>
  23 #include <asm/setup.h>
  24
  25 #include <platform/simcall.h>
  26
  27
  28 static int iss_power_off(struct sys_off_data *unused)
  29 {
  30         pr_info(" ** Called platform_power_off() **\n");
  31         simc_exit(0);
  32         return NOTIFY_DONE;
  33 }
  34
  35 static int iss_restart(struct notifier_block *this,
  36                        unsigned long event, void *ptr)
  37 {
  38         /* Flush and reset the mmu, simulate a processor reset, and
  39          * jump to the reset vector. */
  40         cpu_reset();
  41
  42         return NOTIFY_DONE;
  43 }
  44
  45 static struct notifier_block iss_restart_block = {
  46         .notifier_call = iss_restart,
  47 };
  48
  49 static int
  50 iss_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
  51 {
  52         simc_exit(1);
  53         return NOTIFY_DONE;
  54 }
  55
  56 static struct notifier_block iss_panic_block = {
  57         .notifier_call = iss_panic_event,
  58 };
  59
  60 void __init platform_setup(char **p_cmdline)
  61 {
  62         static void *argv[COMMAND_LINE_SIZE / sizeof(void *)] __initdata;
  63         static char cmdline[COMMAND_LINE_SIZE] __initdata;
  64         int argc = simc_argc();
  65         int argv_size = simc_argv_size();
  66
  67         if (argc > 1) {
  68                 if (argv_size > sizeof(argv)) {
  69                         pr_err("%s: command line too long: argv_size = %d\n",
  70                                __func__, argv_size);
  71                 } else {
  72                         int i;
  73
  74                         cmdline[0] = 0;
  75                         simc_argv((void *)argv);
  76
  77                         for (i = 1; i < argc; ++i) {
  78                                 if (i > 1)
  79                                         strcat(cmdline, " ");
  80                                 strcat(cmdline, argv[i]);
  81                         }
  82                         *p_cmdline = cmdline;
  83                 }
  84         }
  85
  86         atomic_notifier_chain_register(&panic_notifier_list, &iss_panic_block);
  87         register_restart_handler(&iss_restart_block);
  88         register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,
  89                                  SYS_OFF_PRIO_PLATFORM,
  90                                  iss_power_off, NULL);
  91 }