1 /* 2 * arch/sh/kernel/cpu/sh4/clock-sh4.c 3 * 4 * Generic SH-4 support for the clock framework 5 * 6 * Copyright (C) 2005 Paul Mundt 7 * 8 * FRQCR parsing hacked out of arch/sh/kernel/time.c 9 * 10 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka 11 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> 12 * Copyright (C) 2002, 2003, 2004 Paul Mundt 13 * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org> 14 * 15 * This file is subject to the terms and conditions of the GNU General Public 16 * License. See the file "COPYING" in the main directory of this archive 17 * for more details. 18 */ 19 #include <linux/init.h> 20 #include <linux/kernel.h> 21 #include <asm/clock.h> 22 #include <asm/freq.h> 23 #include <asm/io.h> 24 25 static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 1, 1 }; 26 #define bfc_divisors ifc_divisors /* Same */ 27 static int pfc_divisors[] = { 2, 3, 4, 6, 8, 2, 2, 2 }; 28 29 static void master_clk_init(struct clk *clk) 30 { 31 clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0007]; 32 } 33 34 static struct sh_clk_ops sh4_master_clk_ops = { 35 .init = master_clk_init, 36 }; 37 38 static unsigned long module_clk_recalc(struct clk *clk) 39 { 40 int idx = (__raw_readw(FRQCR) & 0x0007); 41 return clk->parent->rate / pfc_divisors[idx]; 42 } 43 44 static struct sh_clk_ops sh4_module_clk_ops = { 45 .recalc = module_clk_recalc, 46 }; 47 48 static unsigned long bus_clk_recalc(struct clk *clk) 49 { 50 int idx = (__raw_readw(FRQCR) >> 3) & 0x0007; 51 return clk->parent->rate / bfc_divisors[idx]; 52 } 53 54 static struct sh_clk_ops sh4_bus_clk_ops = { 55 .recalc = bus_clk_recalc, 56 }; 57 58 static unsigned long cpu_clk_recalc(struct clk *clk) 59 { 60 int idx = (__raw_readw(FRQCR) >> 6) & 0x0007; 61 return clk->parent->rate / ifc_divisors[idx]; 62 } 63 64 static struct sh_clk_ops sh4_cpu_clk_ops = { 65 .recalc = cpu_clk_recalc, 66 }; 67 68 static struct sh_clk_ops *sh4_clk_ops[] = { 69 &sh4_master_clk_ops, 70 &sh4_module_clk_ops, 71 &sh4_bus_clk_ops, 72 &sh4_cpu_clk_ops, 73 }; 74 75 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx) 76 { 77 if (idx < ARRAY_SIZE(sh4_clk_ops)) 78 *ops = sh4_clk_ops[idx]; 79 } 80 81