1/* arch/arm/mach-msm/clock.c 2 * 3 * Copyright (C) 2007 Google, Inc. 4 * Copyright (c) 2007-2010, Code Aurora Forum. All rights reserved. 5 * 6 * This software is licensed under the terms of the GNU General Public 7 * License version 2, as published by the Free Software Foundation, and 8 * may be copied, distributed, and modified under those terms. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 */ 16 17#include <linux/kernel.h> 18#include <linux/init.h> 19#include <linux/module.h> 20#include <linux/list.h> 21#include <linux/err.h> 22#include <linux/clk.h> 23#include <linux/spinlock.h> 24#include <linux/debugfs.h> 25#include <linux/ctype.h> 26#include <linux/pm_qos_params.h> 27#include <mach/clk.h> 28 29#include "clock.h" 30#include "proc_comm.h" 31#include "clock-7x30.h" 32 33static DEFINE_MUTEX(clocks_mutex); 34static DEFINE_SPINLOCK(clocks_lock); 35static LIST_HEAD(clocks); 36struct clk *msm_clocks; 37unsigned msm_num_clocks; 38 39/* 40 * Bitmap of enabled clocks, excluding ACPU which is always 41 * enabled 42 */ 43static DECLARE_BITMAP(clock_map_enabled, NR_CLKS); 44static DEFINE_SPINLOCK(clock_map_lock); 45 46/* 47 * Standard clock functions defined in include/linux/clk.h 48 */ 49struct clk *clk_get(struct device *dev, const char *id) 50{ 51 struct clk *clk; 52 53 mutex_lock(&clocks_mutex); 54 55 list_for_each_entry(clk, &clocks, list) 56 if (!strcmp(id, clk->name) && clk->dev == dev) 57 goto found_it; 58 59 list_for_each_entry(clk, &clocks, list) 60 if (!strcmp(id, clk->name) && clk->dev == NULL) 61 goto found_it; 62 63 clk = ERR_PTR(-ENOENT); 64found_it: 65 mutex_unlock(&clocks_mutex); 66 return clk; 67} 68EXPORT_SYMBOL(clk_get); 69 70void clk_put(struct clk *clk) 71{ 72} 73EXPORT_SYMBOL(clk_put); 74 75int clk_enable(struct clk *clk) 76{ 77 unsigned long flags; 78 spin_lock_irqsave(&clocks_lock, flags); 79 clk->count++; 80 if (clk->count == 1) { 81 clk->ops->enable(clk->id); 82 spin_lock(&clock_map_lock); 83 clock_map_enabled[BIT_WORD(clk->id)] |= BIT_MASK(clk->id); 84 spin_unlock(&clock_map_lock); 85 } 86 spin_unlock_irqrestore(&clocks_lock, flags); 87 return 0; 88} 89EXPORT_SYMBOL(clk_enable); 90 91void clk_disable(struct clk *clk) 92{ 93 unsigned long flags; 94 spin_lock_irqsave(&clocks_lock, flags); 95 BUG_ON(clk->count == 0); 96 clk->count--; 97 if (clk->count == 0) { 98 clk->ops->disable(clk->id); 99 spin_lock(&clock_map_lock); 100 clock_map_enabled[BIT_WORD(clk->id)] &= ~BIT_MASK(clk->id); 101 spin_unlock(&clock_map_lock); 102 } 103 spin_unlock_irqrestore(&clocks_lock, flags); 104} 105EXPORT_SYMBOL(clk_disable); 106 107int clk_reset(struct clk *clk, enum clk_reset_action action) 108{ 109 if (!clk->ops->reset) 110 clk->ops->reset = &pc_clk_reset; 111 return clk->ops->reset(clk->remote_id, action); 112} 113EXPORT_SYMBOL(clk_reset); 114 115unsigned long clk_get_rate(struct clk *clk) 116{ 117 return clk->ops->get_rate(clk->id); 118} 119EXPORT_SYMBOL(clk_get_rate); 120 121int clk_set_rate(struct clk *clk, unsigned long rate) 122{ 123 return clk->ops->set_rate(clk->id, rate); 124} 125EXPORT_SYMBOL(clk_set_rate); 126 127long clk_round_rate(struct clk *clk, unsigned long rate) 128{ 129 return clk->ops->round_rate(clk->id, rate); 130} 131EXPORT_SYMBOL(clk_round_rate); 132 133int clk_set_min_rate(struct clk *clk, unsigned long rate) 134{ 135 return clk->ops->set_min_rate(clk->id, rate); 136} 137EXPORT_SYMBOL(clk_set_min_rate); 138 139int clk_set_max_rate(struct clk *clk, unsigned long rate) 140{ 141 return clk->ops->set_max_rate(clk->id, rate); 142} 143EXPORT_SYMBOL(clk_set_max_rate); 144 145int clk_set_parent(struct clk *clk, struct clk *parent) 146{ 147 return -ENOSYS; 148} 149EXPORT_SYMBOL(clk_set_parent); 150 151struct clk *clk_get_parent(struct clk *clk) 152{ 153 return ERR_PTR(-ENOSYS); 154} 155EXPORT_SYMBOL(clk_get_parent); 156 157int clk_set_flags(struct clk *clk, unsigned long flags) 158{ 159 if (clk == NULL || IS_ERR(clk)) 160 return -EINVAL; 161 return clk->ops->set_flags(clk->id, flags); 162} 163EXPORT_SYMBOL(clk_set_flags); 164 165/* EBI1 is the only shared clock that several clients want to vote on as of 166 * this commit. If this changes in the future, then it might be better to 167 * make clk_min_rate handle the voting or make ebi1_clk_set_min_rate more 168 * generic to support different clocks. 169 */ 170static struct clk *ebi1_clk; 171 172static void __init set_clock_ops(struct clk *clk) 173{ 174 if (!clk->ops) { 175 clk->ops = &clk_ops_pcom; 176 clk->id = clk->remote_id; 177 } 178} 179 180void __init msm_clock_init(struct clk *clock_tbl, unsigned num_clocks) 181{ 182 unsigned n; 183 184 spin_lock_init(&clocks_lock); 185 mutex_lock(&clocks_mutex); 186 msm_clocks = clock_tbl; 187 msm_num_clocks = num_clocks; 188 for (n = 0; n < msm_num_clocks; n++) { 189 set_clock_ops(&msm_clocks[n]); 190 list_add_tail(&msm_clocks[n].list, &clocks); 191 } 192 mutex_unlock(&clocks_mutex); 193 194 ebi1_clk = clk_get(NULL, "ebi1_clk"); 195 BUG_ON(ebi1_clk == NULL); 196 197} 198 199#if defined(CONFIG_DEBUG_FS) 200static struct clk *msm_clock_get_nth(unsigned index) 201{ 202 if (index < msm_num_clocks) 203 return msm_clocks + index; 204 else 205 return 0; 206} 207 208static int clock_debug_rate_set(void *data, u64 val) 209{ 210 struct clk *clock = data; 211 int ret; 212 213 /* Only increases to max rate will succeed, but that's actually good 214 * for debugging purposes. So we don't check for error. */ 215 if (clock->flags & CLK_MAX) 216 clk_set_max_rate(clock, val); 217 if (clock->flags & CLK_MIN) 218 ret = clk_set_min_rate(clock, val); 219 else 220 ret = clk_set_rate(clock, val); 221 if (ret != 0) 222 printk(KERN_ERR "clk_set%s_rate failed (%d)\n", 223 (clock->flags & CLK_MIN) ? "_min" : "", ret); 224 return ret; 225} 226 227static int clock_debug_rate_get(void *data, u64 *val) 228{ 229 struct clk *clock = data; 230 *val = clk_get_rate(clock); 231 return 0; 232} 233 234static int clock_debug_enable_set(void *data, u64 val) 235{ 236 struct clk *clock = data; 237 int rc = 0; 238 239 if (val) 240 rc = clock->ops->enable(clock->id); 241 else 242 clock->ops->disable(clock->id); 243 244 return rc; 245} 246 247static int clock_debug_enable_get(void *data, u64 *val) 248{ 249 struct clk *clock = data; 250 251 *val = clock->ops->is_enabled(clock->id); 252 253 return 0; 254} 255 256static int clock_debug_local_get(void *data, u64 *val) 257{ 258 struct clk *clock = data; 259 260 *val = clock->ops != &clk_ops_pcom; 261 262 return 0; 263} 264 265DEFINE_SIMPLE_ATTRIBUTE(clock_rate_fops, clock_debug_rate_get, 266 clock_debug_rate_set, "%llu\n"); 267DEFINE_SIMPLE_ATTRIBUTE(clock_enable_fops, clock_debug_enable_get, 268 clock_debug_enable_set, "%llu\n"); 269DEFINE_SIMPLE_ATTRIBUTE(clock_local_fops, clock_debug_local_get, 270 NULL, "%llu\n"); 271 272static int __init clock_debug_init(void) 273{ 274 struct dentry *dent_rate, *dent_enable, *dent_local; 275 struct clk *clock; 276 unsigned n = 0; 277 char temp[50], *ptr; 278 279 dent_rate = debugfs_create_dir("clk_rate", 0); 280 if (IS_ERR(dent_rate)) 281 return PTR_ERR(dent_rate); 282 283 dent_enable = debugfs_create_dir("clk_enable", 0); 284 if (IS_ERR(dent_enable)) 285 return PTR_ERR(dent_enable); 286 287 dent_local = debugfs_create_dir("clk_local", NULL); 288 if (IS_ERR(dent_local)) 289 return PTR_ERR(dent_local); 290 291 while ((clock = msm_clock_get_nth(n++)) != 0) { 292 strncpy(temp, clock->dbg_name, ARRAY_SIZE(temp)-1); 293 for (ptr = temp; *ptr; ptr++) 294 *ptr = tolower(*ptr); 295 debugfs_create_file(temp, 0644, dent_rate, 296 clock, &clock_rate_fops); 297 debugfs_create_file(temp, 0644, dent_enable, 298 clock, &clock_enable_fops); 299 debugfs_create_file(temp, S_IRUGO, dent_local, 300 clock, &clock_local_fops); 301 } 302 return 0; 303} 304 305device_initcall(clock_debug_init); 306#endif 307 308/* The bootloader and/or AMSS may have left various clocks enabled. 309 * Disable any clocks that belong to us (CLKFLAG_AUTO_OFF) but have 310 * not been explicitly enabled by a clk_enable() call. 311 */ 312static int __init clock_late_init(void) 313{ 314 unsigned long flags; 315 struct clk *clk; 316 unsigned count = 0; 317 318 mutex_lock(&clocks_mutex); 319 list_for_each_entry(clk, &clocks, list) { 320 if (clk->flags & CLKFLAG_AUTO_OFF) { 321 spin_lock_irqsave(&clocks_lock, flags); 322 if (!clk->count) { 323 count++; 324 clk->ops->auto_off(clk->id); 325 } 326 spin_unlock_irqrestore(&clocks_lock, flags); 327 } 328 } 329 mutex_unlock(&clocks_mutex); 330 pr_info("clock_late_init() disabled %d unused clocks\n", count); 331 return 0; 332} 333 334late_initcall(clock_late_init); 335