drivers/clk/clk-bcm2835.c

   1 /*
   2  * Copyright (C) 2010 Broadcom
   3  * Copyright (C) 2012 Stephen Warren
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 #include <linux/clk-provider.h>
  21 #include <linux/clkdev.h>
  22 #include <linux/clk/bcm2835.h>
  23 #include <linux/of.h>
  24
  25 /*
  26  * These are fixed clocks. They're probably not all root clocks and it may
  27  * be possible to turn them on and off but until this is mapped out better
  28  * it's the only way they can be used.
  29  */
  30 void __init bcm2835_init_clocks(void)
  31 {
  32         struct clk *clk;
  33         int ret;
  34
  35         clk = clk_register_fixed_rate(NULL, "sys_pclk", NULL, CLK_IS_ROOT,
  36                                         250000000);
  37         if (IS_ERR(clk))
  38                 pr_err("sys_pclk not registered\n");
  39
  40         clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT,
  41                                         126000000);
  42         if (IS_ERR(clk))
  43                 pr_err("apb_pclk not registered\n");
  44
  45         clk = clk_register_fixed_rate(NULL, "uart0_pclk", NULL, CLK_IS_ROOT,
  46                                         3000000);
  47         if (IS_ERR(clk))
  48                 pr_err("uart0_pclk not registered\n");
  49         ret = clk_register_clkdev(clk, NULL, "20201000.uart");
  50         if (ret)
  51                 pr_err("uart0_pclk alias not registered\n");
  52
  53         clk = clk_register_fixed_rate(NULL, "uart1_pclk", NULL, CLK_IS_ROOT,
  54                                         125000000);
  55         if (IS_ERR(clk))
  56                 pr_err("uart1_pclk not registered\n");
  57         ret = clk_register_clkdev(clk, NULL, "20215000.uart");
  58         if (ret)
  59                 pr_err("uart1_pclk alias not registered\n");
  60 }