1c8a7ba9eSThomas Chou /* 2c8a7ba9eSThomas Chou * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw> 3c8a7ba9eSThomas Chou * 4c8a7ba9eSThomas Chou * SPDX-License-Identifier: GPL-2.0+ 5c8a7ba9eSThomas Chou */ 6c8a7ba9eSThomas Chou 7c8a7ba9eSThomas Chou #include <common.h> 8c8a7ba9eSThomas Chou #include <dm.h> 9c8a7ba9eSThomas Chou #include <errno.h> 10c8a7ba9eSThomas Chou #include <timer.h> 11c8a7ba9eSThomas Chou 12*579eb5a0SBin Meng DECLARE_GLOBAL_DATA_PTR; 13*579eb5a0SBin Meng 14c8a7ba9eSThomas Chou /* 15435ae76eSBin Meng * Implement a timer uclass to work with lib/time.c. The timer is usually 16c8a7ba9eSThomas Chou * a 32 bits free-running up counter. The get_rate() method is used to get 17c8a7ba9eSThomas Chou * the input clock frequency of the timer. The get_count() method is used 18435ae76eSBin Meng * to get the current 32 bits count value. If the hardware is counting down, 19c8a7ba9eSThomas Chou * the value should be inversed inside the method. There may be no real 20c8a7ba9eSThomas Chou * tick, and no timer interrupt. 21c8a7ba9eSThomas Chou */ 22c8a7ba9eSThomas Chou 23c8a7ba9eSThomas Chou int timer_get_count(struct udevice *dev, unsigned long *count) 24c8a7ba9eSThomas Chou { 25c8a7ba9eSThomas Chou const struct timer_ops *ops = device_get_ops(dev); 26c8a7ba9eSThomas Chou 27c8a7ba9eSThomas Chou if (!ops->get_count) 28c8a7ba9eSThomas Chou return -ENOSYS; 29c8a7ba9eSThomas Chou 30c8a7ba9eSThomas Chou return ops->get_count(dev, count); 31c8a7ba9eSThomas Chou } 32c8a7ba9eSThomas Chou 33c8a7ba9eSThomas Chou unsigned long timer_get_rate(struct udevice *dev) 34c8a7ba9eSThomas Chou { 35c8a7ba9eSThomas Chou struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); 36c8a7ba9eSThomas Chou 37c8a7ba9eSThomas Chou return uc_priv->clock_rate; 38c8a7ba9eSThomas Chou } 39c8a7ba9eSThomas Chou 40*579eb5a0SBin Meng static int timer_pre_probe(struct udevice *dev) 41*579eb5a0SBin Meng { 42*579eb5a0SBin Meng struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); 43*579eb5a0SBin Meng 44*579eb5a0SBin Meng uc_priv->clock_rate = fdtdec_get_int(gd->fdt_blob, dev->of_offset, 45*579eb5a0SBin Meng "clock-frequency", 0); 46*579eb5a0SBin Meng 47*579eb5a0SBin Meng return 0; 48*579eb5a0SBin Meng } 49*579eb5a0SBin Meng 50c8a7ba9eSThomas Chou UCLASS_DRIVER(timer) = { 51c8a7ba9eSThomas Chou .id = UCLASS_TIMER, 52c8a7ba9eSThomas Chou .name = "timer", 53*579eb5a0SBin Meng .pre_probe = timer_pre_probe, 54c8a7ba9eSThomas Chou .per_device_auto_alloc_size = sizeof(struct timer_dev_priv), 55c8a7ba9eSThomas Chou }; 56