text: /*
   * SPDX-License-Identifier: BSD-2-Clause
   *
   * Copyright (c) 2020 Western Digital Corporation or its affiliates.
   *
   * Authors:
   *   Anup Patel <anup.patel@wdc.com>
   */
  
  #include <sbi/sbi_scratch.h>
  #include <sbi_utils/fdt/fdt_helper.h>
  #include <sbi_utils/timer/fdt_timer.h>
  
  extern struct fdt_timer fdt_timer_clint;
  
  static struct fdt_timer *timer_drivers[] = {
  	&fdt_timer_clint
  };
  
  static u64 dummy_value(void)
  {
  	return 0;
  }
  
  static void dummy_event_stop(void)
  {
  }
  
  static void dummy_event_start(u64 next_event)
  {
  }
  
  static struct fdt_timer dummy = {
  	.match_table = NULL,
  	.cold_init = NULL,
  	.warm_init = NULL,
  	.exit = NULL,
  	.value = dummy_value,
  	.event_stop = dummy_event_stop,
  	.event_start = dummy_event_start
  };
  
  static struct fdt_timer *current_driver = &dummy;
  
  u64 fdt_timer_value(void)
  {
  	return current_driver->value();
  }
  
  void fdt_timer_event_stop(void)
  {
  	current_driver->event_stop();
  }
  
  void fdt_timer_event_start(u64 next_event)
  {
  	current_driver->event_start(next_event);
  }
  
  void fdt_timer_exit(void)
  {
  	if (current_driver->exit)
  		current_driver->exit();
  }
  
  static int fdt_timer_warm_init(void)
  {
  	if (current_driver->warm_init)
  		return current_driver->warm_init();
  	return 0;
  }
  
  static int fdt_timer_cold_init(void)
  {
  	int pos, noff, rc;
  	struct fdt_timer *drv;
  	const struct fdt_match *match;
  	void *fdt = sbi_scratch_thishart_arg1_ptr();
  
  	for (pos = 0; pos < array_size(timer_drivers); pos++) {
  		drv = timer_drivers[pos];
  
  		noff = -1;
  		while ((noff = fdt_find_match(fdt, noff,
  					drv->match_table, &match)) >= 0) {
  			if (drv->cold_init) {
  				rc = drv->cold_init(fdt, noff, match);
  				if (rc)
  					return rc;
  			}
  			current_driver = drv;
  		}
  
  		if (current_driver != &dummy)
  			break;
  	}
  
  	return 0;
  }
  
  int fdt_timer_init(bool cold_boot)
  {
  	int rc;
  
  	if (cold_boot) {
  		rc = fdt_timer_cold_init();
  		if (rc)
  			return rc;
  	}
  
  	return fdt_timer_warm_init();
  }
  