1 /* 2 * arch/sh/kernel/cpu/sh3/clock-sh7705.c 3 * 4 * SH7705 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 /* 26 * SH7705 uses the same divisors as the generic SH-3 case, it's just the 27 * FRQCR layout that is a bit different.. 28 */ 29 static int stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 }; 30 static int ifc_divisors[] = { 1, 2, 3, 4, 1, 1, 1, 1 }; 31 static int pfc_divisors[] = { 1, 2, 3, 4, 6, 1, 1, 1 }; 32 33 static void master_clk_init(struct clk *clk) 34 { 35 clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0003]; 36 } 37 38 static struct sh_clk_ops sh7705_master_clk_ops = { 39 .init = master_clk_init, 40 }; 41 42 static unsigned long module_clk_recalc(struct clk *clk) 43 { 44 int idx = __raw_readw(FRQCR) & 0x0003; 45 return clk->parent->rate / pfc_divisors[idx]; 46 } 47 48 static struct sh_clk_ops sh7705_module_clk_ops = { 49 .recalc = module_clk_recalc, 50 }; 51 52 static unsigned long bus_clk_recalc(struct clk *clk) 53 { 54 int idx = (__raw_readw(FRQCR) & 0x0300) >> 8; 55 return clk->parent->rate / stc_multipliers[idx]; 56 } 57 58 static struct sh_clk_ops sh7705_bus_clk_ops = { 59 .recalc = bus_clk_recalc, 60 }; 61 62 static unsigned long cpu_clk_recalc(struct clk *clk) 63 { 64 int idx = (__raw_readw(FRQCR) & 0x0030) >> 4; 65 return clk->parent->rate / ifc_divisors[idx]; 66 } 67 68 static struct sh_clk_ops sh7705_cpu_clk_ops = { 69 .recalc = cpu_clk_recalc, 70 }; 71 72 static struct sh_clk_ops *sh7705_clk_ops[] = { 73 &sh7705_master_clk_ops, 74 &sh7705_module_clk_ops, 75 &sh7705_bus_clk_ops, 76 &sh7705_cpu_clk_ops, 77 }; 78 79 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx) 80 { 81 if (idx < ARRAY_SIZE(sh7705_clk_ops)) 82 *ops = sh7705_clk_ops[idx]; 83 } 84 85