arch/mips/loongson64/time.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
   4  * Author: Fuxin Zhang, zhangfx@lemote.com
   5  *
   6  * Copyright (C) 2009 Lemote Inc.
   7  * Author: Wu Zhangjin, wuzhangjin@gmail.com
   8  */
   9
  10 #include <asm/time.h>
  11 #include <asm/hpet.h>
  12
  13 #include <loongson.h>
  14 #include <linux/clk.h>
  15 #include <linux/of_clk.h>
  16
  17 void __init plat_time_init(void)
  18 {
  19         struct clk *clk;
  20         struct device_node *np;
  21
  22         if (loongson_sysconf.fw_interface == LOONGSON_DTB) {
  23                 of_clk_init(NULL);
  24
  25                 np = of_get_cpu_node(0, NULL);
  26                 if (!np) {
  27                         pr_err("Failed to get CPU node\n");
  28                         return;
  29                 }
  30
  31                 clk = of_clk_get(np, 0);
  32                 if (IS_ERR(clk)) {
  33                         pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk));
  34                         return;
  35                 }
  36
  37                 cpu_clock_freq = clk_get_rate(clk);
  38                 clk_put(clk);
  39         }
  40
  41         /* setup mips r4k timer */
  42         mips_hpt_frequency = cpu_clock_freq / 2;
  43
  44 #ifdef CONFIG_RS780_HPET
  45         setup_hpet_timer();
  46 #endif
  47 }