arch/avr32/mach-at32ap/clock.c

   1 /*
   2  * Clock management for AT32AP CPUs
   3  *
   4  * Copyright (C) 2006 Atmel Corporation
   5  *
   6  * Based on arch/arm/mach-at91/clock.c
   7  *   Copyright (C) 2005 David Brownell
   8  *   Copyright (C) 2005 Ivan Kokshaysky
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14 #include <linux/clk.h>
  15 #include <linux/err.h>
  16 #include <linux/device.h>
  17 #include <linux/string.h>
  18
  19 #include "clock.h"
  20
  21 static DEFINE_SPINLOCK(clk_lock);
  22
  23 struct clk *clk_get(struct device *dev, const char *id)
  24 {
  25         int i;
  26
  27         for (i = 0; i < at32_nr_clocks; i++) {
  28                 struct clk *clk = at32_clock_list[i];
  29
  30                 if (clk->dev == dev && strcmp(id, clk->name) == 0)
  31                         return clk;
  32         }
  33
  34         return ERR_PTR(-ENOENT);
  35 }
  36 EXPORT_SYMBOL(clk_get);
  37
  38 void clk_put(struct clk *clk)
  39 {
  40         /* clocks are static for now, we can't free them */
  41 }
  42 EXPORT_SYMBOL(clk_put);
  43
  44 static void __clk_enable(struct clk *clk)
  45 {
  46         if (clk->parent)
  47                 __clk_enable(clk->parent);
  48         if (clk->users++ == 0 && clk->mode)
  49                 clk->mode(clk, 1);
  50 }
  51
  52 int clk_enable(struct clk *clk)
  53 {
  54         unsigned long flags;
  55
  56         spin_lock_irqsave(&clk_lock, flags);
  57         __clk_enable(clk);
  58         spin_unlock_irqrestore(&clk_lock, flags);
  59
  60         return 0;
  61 }
  62 EXPORT_SYMBOL(clk_enable);
  63
  64 static void __clk_disable(struct clk *clk)
  65 {
  66         if (clk->users == 0) {
  67                 printk(KERN_ERR "%s: mismatched disable\n", clk->name);
  68                 WARN_ON(1);
  69                 return;
  70         }
  71
  72         if (--clk->users == 0 && clk->mode)
  73                 clk->mode(clk, 0);
  74         if (clk->parent)
  75                 __clk_disable(clk->parent);
  76 }
  77
  78 void clk_disable(struct clk *clk)
  79 {
  80         unsigned long flags;
  81
  82         spin_lock_irqsave(&clk_lock, flags);
  83         __clk_disable(clk);
  84         spin_unlock_irqrestore(&clk_lock, flags);
  85 }
  86 EXPORT_SYMBOL(clk_disable);
  87
  88 unsigned long clk_get_rate(struct clk *clk)
  89 {
  90         unsigned long flags;
  91         unsigned long rate;
  92
  93         spin_lock_irqsave(&clk_lock, flags);
  94         rate = clk->get_rate(clk);
  95         spin_unlock_irqrestore(&clk_lock, flags);
  96
  97         return rate;
  98 }
  99 EXPORT_SYMBOL(clk_get_rate);
 100
 101 long clk_round_rate(struct clk *clk, unsigned long rate)
 102 {
 103         unsigned long flags, actual_rate;
 104
 105         if (!clk->set_rate)
 106                 return -ENOSYS;
 107
 108         spin_lock_irqsave(&clk_lock, flags);
 109         actual_rate = clk->set_rate(clk, rate, 0);
 110         spin_unlock_irqrestore(&clk_lock, flags);
 111
 112         return actual_rate;
 113 }
 114 EXPORT_SYMBOL(clk_round_rate);
 115
 116 int clk_set_rate(struct clk *clk, unsigned long rate)
 117 {
 118         unsigned long flags;
 119         long ret;
 120
 121         if (!clk->set_rate)
 122                 return -ENOSYS;
 123
 124         spin_lock_irqsave(&clk_lock, flags);
 125         ret = clk->set_rate(clk, rate, 1);
 126         spin_unlock_irqrestore(&clk_lock, flags);
 127
 128         return (ret < 0) ? ret : 0;
 129 }
 130 EXPORT_SYMBOL(clk_set_rate);
 131
 132 int clk_set_parent(struct clk *clk, struct clk *parent)
 133 {
 134         unsigned long flags;
 135         int ret;
 136
 137         if (!clk->set_parent)
 138                 return -ENOSYS;
 139
 140         spin_lock_irqsave(&clk_lock, flags);
 141         ret = clk->set_parent(clk, parent);
 142         spin_unlock_irqrestore(&clk_lock, flags);
 143
 144         return ret;
 145 }
 146 EXPORT_SYMBOL(clk_set_parent);
 147
 148 struct clk *clk_get_parent(struct clk *clk)
 149 {
 150         return clk->parent;
 151 }
 152 EXPORT_SYMBOL(clk_get_parent);
 153
 154
 155
 156 #ifdef CONFIG_DEBUG_FS
 157
 158 /* /sys/kernel/debug/at32ap_clk */
 159
 160 #include <linux/io.h>
 161 #include <linux/debugfs.h>
 162 #include <linux/seq_file.h>
 163 #include "pm.h"
 164
 165
 166 #define NEST_DELTA      2
 167 #define NEST_MAX        6
 168
 169 struct clkinf {
 170         struct seq_file *s;
 171         unsigned        nest;
 172 };
 173
 174 static void
 175 dump_clock(struct clk *parent, struct clkinf *r)
 176 {
 177         unsigned        nest = r->nest;
 178         char            buf[16 + NEST_MAX];
 179         struct clk      *clk;
 180         unsigned        i;
 181
 182         /* skip clocks coupled to devices that aren't registered */
 183         if (parent->dev && !parent->dev->bus_id[0] && !parent->users)
 184                 return;
 185
 186         /* <nest spaces> name <pad to end> */
 187         memset(buf, ' ', sizeof(buf) - 1);
 188         buf[sizeof(buf) - 1] = 0;
 189         i = strlen(parent->name);
 190         memcpy(buf + nest, parent->name,
 191                         min(i, (unsigned)(sizeof(buf) - 1 - nest)));
 192
 193         seq_printf(r->s, "%s%c users=%2d %-3s %9ld Hz",
 194                 buf, parent->set_parent ? '*' : ' ',
 195                 parent->users,
 196                 parent->users ? "on" : "off",   /* NOTE: not-paranoid!! */
 197                 clk_get_rate(parent));
 198         if (parent->dev)
 199                 seq_printf(r->s, ", for %s", parent->dev->bus_id);
 200         seq_printf(r->s, "\n");
 201
 202         /* cost of this scan is small, but not linear... */
 203         r->nest = nest + NEST_DELTA;
 204         for (i = 3; i < at32_nr_clocks; i++) {
 205                 clk = at32_clock_list[i];
 206                 if (clk->parent == parent)
 207                         dump_clock(clk, r);
 208         }
 209         r->nest = nest;
 210 }
 211
 212 static int clk_show(struct seq_file *s, void *unused)
 213 {
 214         struct clkinf   r;
 215         int             i;
 216
 217         /* show all the power manager registers */
 218         seq_printf(s, "MCCTRL  = %8x\n", pm_readl(MCCTRL));
 219         seq_printf(s, "CKSEL   = %8x\n", pm_readl(CKSEL));
 220         seq_printf(s, "CPUMASK = %8x\n", pm_readl(CPU_MASK));
 221         seq_printf(s, "HSBMASK = %8x\n", pm_readl(HSB_MASK));
 222         seq_printf(s, "PBAMASK = %8x\n", pm_readl(PBA_MASK));
 223         seq_printf(s, "PBBMASK = %8x\n", pm_readl(PBB_MASK));
 224         seq_printf(s, "PLL0    = %8x\n", pm_readl(PLL0));
 225         seq_printf(s, "PLL1    = %8x\n", pm_readl(PLL1));
 226         seq_printf(s, "IMR     = %8x\n", pm_readl(IMR));
 227         for (i = 0; i < 8; i++) {
 228                 if (i == 5)
 229                         continue;
 230                 seq_printf(s, "GCCTRL%d = %8x\n", i, pm_readl(GCCTRL(i)));
 231         }
 232
 233         seq_printf(s, "\n");
 234
 235         /* show clock tree as derived from the three oscillators
 236          * we "know" are at the head of the list
 237          */
 238         r.s = s;
 239         r.nest = 0;
 240         dump_clock(at32_clock_list[0], &r);
 241         dump_clock(at32_clock_list[1], &r);
 242         dump_clock(at32_clock_list[2], &r);
 243
 244         return 0;
 245 }
 246
 247 static int clk_open(struct inode *inode, struct file *file)
 248 {
 249         return single_open(file, clk_show, NULL);
 250 }
 251
 252 static const struct file_operations clk_operations = {
 253         .open           = clk_open,
 254         .read           = seq_read,
 255         .llseek         = seq_lseek,
 256         .release        = single_release,
 257 };
 258
 259 static int __init clk_debugfs_init(void)
 260 {
 261         (void) debugfs_create_file("at32ap_clk", S_IFREG | S_IRUGO,
 262                         NULL, NULL, &clk_operations);
 263
 264         return 0;
 265 }
 266 postcore_initcall(clk_debugfs_init);
 267
 268 #endif