| 1 | /* |
| 2 | * Ralink RT288X clock API |
| 3 | * |
| 4 | * Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published |
| 8 | * by the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/err.h> |
| 15 | #include <linux/clk.h> |
| 16 | |
| 17 | #include <asm/mach-ralink/common.h> |
| 18 | #include <asm/mach-ralink/rt288x.h> |
| 19 | #include <asm/mach-ralink/rt288x_regs.h> |
| 20 | #include "common.h" |
| 21 | |
| 22 | struct clk { |
| 23 | unsigned long rate; |
| 24 | }; |
| 25 | |
| 26 | static struct clk rt288x_cpu_clk; |
| 27 | static struct clk rt288x_sys_clk; |
| 28 | static struct clk rt288x_wdt_clk; |
| 29 | static struct clk rt288x_uart_clk; |
| 30 | |
| 31 | void __init rt288x_clocks_init(void) |
| 32 | { |
| 33 | u32 t; |
| 34 | |
| 35 | t = rt288x_sysc_rr(SYSC_REG_SYSTEM_CONFIG); |
| 36 | t = ((t >> SYSTEM_CONFIG_CPUCLK_SHIFT) & SYSTEM_CONFIG_CPUCLK_MASK); |
| 37 | |
| 38 | switch (t) { |
| 39 | case SYSTEM_CONFIG_CPUCLK_250: |
| 40 | rt288x_cpu_clk.rate = 250000000; |
| 41 | break; |
| 42 | case SYSTEM_CONFIG_CPUCLK_266: |
| 43 | rt288x_cpu_clk.rate = 266666667; |
| 44 | break; |
| 45 | case SYSTEM_CONFIG_CPUCLK_280: |
| 46 | rt288x_cpu_clk.rate = 280000000; |
| 47 | break; |
| 48 | case SYSTEM_CONFIG_CPUCLK_300: |
| 49 | rt288x_cpu_clk.rate = 300000000; |
| 50 | break; |
| 51 | } |
| 52 | |
| 53 | rt288x_sys_clk.rate = rt288x_cpu_clk.rate / 2; |
| 54 | rt288x_uart_clk.rate = rt288x_sys_clk.rate; |
| 55 | rt288x_wdt_clk.rate = rt288x_sys_clk.rate; |
| 56 | } |
| 57 | |
| 58 | /* |
| 59 | * Linux clock API |
| 60 | */ |
| 61 | struct clk *clk_get(struct device *dev, const char *id) |
| 62 | { |
| 63 | if (!strcmp(id, "sys")) |
| 64 | return &rt288x_sys_clk; |
| 65 | |
| 66 | if (!strcmp(id, "cpu")) |
| 67 | return &rt288x_cpu_clk; |
| 68 | |
| 69 | if (!strcmp(id, "wdt")) |
| 70 | return &rt288x_wdt_clk; |
| 71 | |
| 72 | if (!strcmp(id, "uart")) |
| 73 | return &rt288x_uart_clk; |
| 74 | |
| 75 | return ERR_PTR(-ENOENT); |
| 76 | } |
| 77 | EXPORT_SYMBOL(clk_get); |
| 78 | |
| 79 | int clk_enable(struct clk *clk) |
| 80 | { |
| 81 | return 0; |
| 82 | } |
| 83 | EXPORT_SYMBOL(clk_enable); |
| 84 | |
| 85 | void clk_disable(struct clk *clk) |
| 86 | { |
| 87 | } |
| 88 | EXPORT_SYMBOL(clk_disable); |
| 89 | |
| 90 | unsigned long clk_get_rate(struct clk *clk) |
| 91 | { |
| 92 | return clk->rate; |
| 93 | } |
| 94 | EXPORT_SYMBOL(clk_get_rate); |
| 95 | |
| 96 | void clk_put(struct clk *clk) |
| 97 | { |
| 98 | } |
| 99 | EXPORT_SYMBOL(clk_put); |
| 100 | |
