LXR linux/drivers/clk/versatile/clk-vexpress.c

   1/*
   2 * This program is free software; you can redistribute it and/or modify
   3 * it under the terms of the GNU General Public License version 2 as
   4 * published by the Free Software Foundation.
   5 *
   6 * This program is distributed in the hope that it will be useful,
   7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9 * GNU General Public License for more details.
  10 *
  11 * Copyright (C) 2012 ARM Limited
  12 */
  13
  14#include <linux/amba/sp810.h>
  15#include <linux/clkdev.h>
  16#include <linux/clk-provider.h>
  17#include <linux/err.h>
  18#include <linux/vexpress.h>
  19
  20static struct clk *vexpress_sp810_timerclken[4];
  21static DEFINE_SPINLOCK(vexpress_sp810_lock);
  22
  23static void __init vexpress_sp810_init(void __iomem *base)
  24{
  25        int i;
  26
  27        if (WARN_ON(!base))
  28                return;
  29
  30        for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++) {
  31                char name[12];
  32                const char *parents[] = {
  33                        "v2m:refclk32khz", /* REFCLK */
  34                        "v2m:refclk1mhz" /* TIMCLK */
  35                };
  36
  37                snprintf(name, ARRAY_SIZE(name), "timerclken%d", i);
  38
  39                vexpress_sp810_timerclken[i] = clk_register_mux(NULL, name,
  40                                parents, 2, CLK_SET_RATE_NO_REPARENT,
  41                                base + SCCTRL, SCCTRL_TIMERENnSEL_SHIFT(i), 1,
  42                                0, &vexpress_sp810_lock);
  43
  44                if (WARN_ON(IS_ERR(vexpress_sp810_timerclken[i])))
  45                        break;
  46        }
  47}
  48
  49
  50static const char * const vexpress_clk_24mhz_periphs[] __initconst = {
  51        "mb:uart0", "mb:uart1", "mb:uart2", "mb:uart3",
  52        "mb:mmci", "mb:kmi0", "mb:kmi1"
  53};
  54
  55void __init vexpress_clk_init(void __iomem *sp810_base)
  56{
  57        struct clk *clk;
  58        int i;
  59
  60        clk = clk_register_fixed_rate(NULL, "dummy_apb_pclk", NULL,
  61                        CLK_IS_ROOT, 0);
  62        WARN_ON(clk_register_clkdev(clk, "apb_pclk", NULL));
  63
  64        clk = clk_register_fixed_rate(NULL, "v2m:clk_24mhz", NULL,
  65                        CLK_IS_ROOT, 24000000);
  66        for (i = 0; i < ARRAY_SIZE(vexpress_clk_24mhz_periphs); i++)
  67                WARN_ON(clk_register_clkdev(clk, NULL,
  68                                vexpress_clk_24mhz_periphs[i]));
  69
  70        clk = clk_register_fixed_rate(NULL, "v2m:refclk32khz", NULL,
  71                        CLK_IS_ROOT, 32768);
  72        WARN_ON(clk_register_clkdev(clk, NULL, "v2m:wdt"));
  73
  74        clk = clk_register_fixed_rate(NULL, "v2m:refclk1mhz", NULL,
  75                        CLK_IS_ROOT, 1000000);
  76
  77        vexpress_sp810_init(sp810_base);
  78
  79        for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++)
  80                WARN_ON(clk_set_parent(vexpress_sp810_timerclken[i], clk));
  81
  82        WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[0],
  83                                "v2m-timer0", "sp804"));
  84        WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[1],
  85                                "v2m-timer1", "sp804"));
  86}
  87