LXR linux/arch/sh/kernel/cpu/sh4/clock-sh4.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * arch/sh/kernel/cpu/sh4/clock-sh4.c
   4 *
   5 * Generic SH-4 support for the clock framework
   6 *
   7 *  Copyright (C) 2005  Paul Mundt
   8 *
   9 * FRQCR parsing hacked out of arch/sh/kernel/time.c
  10 *
  11 *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
  12 *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
  13 *  Copyright (C) 2002, 2003, 2004  Paul Mundt
  14 *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org>
  15 */
  16#include <linux/init.h>
  17#include <linux/kernel.h>
  18#include <asm/clock.h>
  19#include <asm/freq.h>
  20#include <asm/io.h>
  21
  22static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 1, 1 };
  23#define bfc_divisors ifc_divisors       /* Same */
  24static int pfc_divisors[] = { 2, 3, 4, 6, 8, 2, 2, 2 };
  25
  26static void master_clk_init(struct clk *clk)
  27{
  28        clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0007];
  29}
  30
  31static struct sh_clk_ops sh4_master_clk_ops = {
  32        .init           = master_clk_init,
  33};
  34
  35static unsigned long module_clk_recalc(struct clk *clk)
  36{
  37        int idx = (__raw_readw(FRQCR) & 0x0007);
  38        return clk->parent->rate / pfc_divisors[idx];
  39}
  40
  41static struct sh_clk_ops sh4_module_clk_ops = {
  42        .recalc         = module_clk_recalc,
  43};
  44
  45static unsigned long bus_clk_recalc(struct clk *clk)
  46{
  47        int idx = (__raw_readw(FRQCR) >> 3) & 0x0007;
  48        return clk->parent->rate / bfc_divisors[idx];
  49}
  50
  51static struct sh_clk_ops sh4_bus_clk_ops = {
  52        .recalc         = bus_clk_recalc,
  53};
  54
  55static unsigned long cpu_clk_recalc(struct clk *clk)
  56{
  57        int idx = (__raw_readw(FRQCR) >> 6) & 0x0007;
  58        return clk->parent->rate / ifc_divisors[idx];
  59}
  60
  61static struct sh_clk_ops sh4_cpu_clk_ops = {
  62        .recalc         = cpu_clk_recalc,
  63};
  64
  65static struct sh_clk_ops *sh4_clk_ops[] = {
  66        &sh4_master_clk_ops,
  67        &sh4_module_clk_ops,
  68        &sh4_bus_clk_ops,
  69        &sh4_cpu_clk_ops,
  70};
  71
  72void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
  73{
  74        if (idx < ARRAY_SIZE(sh4_clk_ops))
  75                *ops = sh4_clk_ops[idx];
  76}
  77
  78