1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * arch/sh/kernel/cpu/sh3/clock-sh3.c 4 * 5 * Generic SH-3 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 stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 }; 23 static int ifc_divisors[] = { 1, 2, 3, 4, 1, 1, 1, 1 }; 24 static int pfc_divisors[] = { 1, 2, 3, 4, 6, 1, 1, 1 }; 25 26 static void master_clk_init(struct clk *clk) 27 { 28 int frqcr = __raw_readw(FRQCR); 29 int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003); 30 31 clk->rate *= pfc_divisors[idx]; 32 } 33 34 static struct sh_clk_ops sh3_master_clk_ops = { 35 .init = master_clk_init, 36 }; 37 38 static unsigned long module_clk_recalc(struct clk *clk) 39 { 40 int frqcr = __raw_readw(FRQCR); 41 int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003); 42 43 return clk->parent->rate / pfc_divisors[idx]; 44 } 45 46 static struct sh_clk_ops sh3_module_clk_ops = { 47 .recalc = module_clk_recalc, 48 }; 49 50 static unsigned long bus_clk_recalc(struct clk *clk) 51 { 52 int frqcr = __raw_readw(FRQCR); 53 int idx = ((frqcr & 0x8000) >> 13) | ((frqcr & 0x0030) >> 4); 54 55 return clk->parent->rate / stc_multipliers[idx]; 56 } 57 58 static struct sh_clk_ops sh3_bus_clk_ops = { 59 .recalc = bus_clk_recalc, 60 }; 61 62 static unsigned long cpu_clk_recalc(struct clk *clk) 63 { 64 int frqcr = __raw_readw(FRQCR); 65 int idx = ((frqcr & 0x4000) >> 12) | ((frqcr & 0x000c) >> 2); 66 67 return clk->parent->rate / ifc_divisors[idx]; 68 } 69 70 static struct sh_clk_ops sh3_cpu_clk_ops = { 71 .recalc = cpu_clk_recalc, 72 }; 73 74 static struct sh_clk_ops *sh3_clk_ops[] = { 75 &sh3_master_clk_ops, 76 &sh3_module_clk_ops, 77 &sh3_bus_clk_ops, 78 &sh3_cpu_clk_ops, 79 }; 80 81 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx) 82 { 83 if (idx < ARRAY_SIZE(sh3_clk_ops)) 84 *ops = sh3_clk_ops[idx]; 85 } 86 87