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
  22 static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 1, 1 };
  23 #define bfc_divisors ifc_divisors       /* Same */
  24 static int pfc_divisors[] = { 2, 3, 4, 6, 8, 2, 2, 2 };
  25
  26 static void master_clk_init(struct clk *clk)
  27 {
  28         clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0007];
  29 }
  30
  31 static struct sh_clk_ops sh4_master_clk_ops = {
  32         .init           = master_clk_init,
  33 };
  34
  35 static 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
  41 static struct sh_clk_ops sh4_module_clk_ops = {
  42         .recalc         = module_clk_recalc,
  43 };
  44
  45 static 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
  51 static struct sh_clk_ops sh4_bus_clk_ops = {
  52         .recalc         = bus_clk_recalc,
  53 };
  54
  55 static 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
  61 static struct sh_clk_ops sh4_cpu_clk_ops = {
  62         .recalc         = cpu_clk_recalc,
  63 };
  64
  65 static 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
  72 void __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