arch/arm/mach-mediatek/mediatek.c

   1 /*
   2  * Device Tree support for Mediatek SoCs
   3  *
   4  * Copyright (c) 2014 MundoReader S.L.
   5  * Author: Matthias Brugger <matthias.bgg@gmail.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17 #include <linux/init.h>
  18 #include <asm/mach/arch.h>
  19 #include <linux/of.h>
  20 #include <linux/clk-provider.h>
  21 #include <linux/clocksource.h>
  22
  23
  24 #define GPT6_CON_MT65xx 0x10008060
  25 #define GPT_ENABLE      0x31
  26
  27 static void __init mediatek_timer_init(void)
  28 {
  29         void __iomem *gpt_base;
  30
  31         if (of_machine_is_compatible("mediatek,mt6589") ||
  32             of_machine_is_compatible("mediatek,mt8135") ||
  33             of_machine_is_compatible("mediatek,mt8127")) {
  34                 /* turn on GPT6 which ungates arch timer clocks */
  35                 gpt_base = ioremap(GPT6_CON_MT65xx, 0x04);
  36
  37                 /* enable clock and set to free-run */
  38                 writel(GPT_ENABLE, gpt_base);
  39                 iounmap(gpt_base);
  40         }
  41
  42         of_clk_init(NULL);
  43         clocksource_probe();
  44 };
  45
  46 static const char * const mediatek_board_dt_compat[] = {
  47         "mediatek,mt6589",
  48         "mediatek,mt6592",
  49         "mediatek,mt8127",
  50         "mediatek,mt8135",
  51         NULL,
  52 };
  53
  54 DT_MACHINE_START(MEDIATEK_DT, "Mediatek Cortex-A7 (Device Tree)")
  55         .dt_compat      = mediatek_board_dt_compat,
  56         .init_time      = mediatek_timer_init,
  57 MACHINE_END