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 <mach/chip.h>
  20
  21 #include "clock.h"
  22
  23 static DEFINE_SPINLOCK(clk_lock);
  24
  25 struct clk *clk_get(struct device *dev, const char *id)
  26 {
  27         int i;
  28
  29         for (i = 0; i < at32_nr_clocks; i++) {
  30                 struct clk *clk = at32_clock_list[i];
  31
  32                 if (clk->dev == dev && strcmp(id, clk->name) == 0)
  33                         return clk;
  34         }
  35
  36         return ERR_PTR(-ENOENT);
  37 }
  38 EXPORT_SYMBOL(clk_get);
  39
  40 void clk_put(struct clk *clk)
  41 {
  42         /* clocks are static for now, we can't free them */
  43 }
  44 EXPORT_SYMBOL(clk_put);
  45
  46 static void __clk_enable(struct clk *clk)
  47 {
  48         if (clk->parent)
  49                 __clk_enable(clk->parent);
  50         if (clk->users++ == 0 && clk->mode)
  51                 clk->mode(clk, 1);
  52 }
  53
  54 int clk_enable(struct clk *clk)
  55 {
  56         unsigned long flags;
  57
  58         spin_lock_irqsave(&clk_lock, flags);
  59         __clk_enable(clk);
  60         spin_unlock_irqrestore(&clk_lock, flags);
  61
  62         return 0;
  63 }
  64 EXPORT_SYMBOL(clk_enable);
  65
  66 static void __clk_disable(struct clk *clk)
  67 {
  68         if (clk->users == 0) {
  69                 printk(KERN_ERR "%s: mismatched disable\n", clk->name);
  70                 WARN_ON(1);
  71                 return;
  72         }
  73
  74         if (--clk->users == 0 && clk->mode)
  75                 clk->mode(clk, 0);
  76         if (clk->parent)
  77                 __clk_disable(clk->parent);
  78 }
  79
  80 void clk_disable(struct clk *clk)
  81 {
  82         unsigned long flags;
  83
  84         spin_lock_irqsave(&clk_lock, flags);
  85         __clk_disable(clk);
  86         spin_unlock_irqrestore(&clk_lock, flags);
  87 }
  88 EXPORT_SYMBOL(clk_disable);
  89
  90 unsigned long clk_get_rate(struct clk *clk)
  91 {
  92         unsigned long flags;
  93         unsigned long rate;
  94
  95         spin_lock_irqsave(&clk_lock, flags);
  96         rate = clk->get_rate(clk);
  97         spin_unlock_irqrestore(&clk_lock, flags);
  98
  99         return rate;
 100 }
 101 EXPORT_SYMBOL(clk_get_rate);
 102
 103 long clk_round_rate(struct clk *clk, unsigned long rate)
 104 {
 105         unsigned long flags, actual_rate;
 106
 107         if (!clk->set_rate)
 108                 return -ENOSYS;
 109
 110         spin_lock_irqsave(&clk_lock, flags);
 111         actual_rate = clk->set_rate(clk, rate, 0);
 112         spin_unlock_irqrestore(&clk_lock, flags);
 113
 114         return actual_rate;
 115 }
 116 EXPORT_SYMBOL(clk_round_rate);
 117
 118 int clk_set_rate(struct clk *clk, unsigned long rate)
 119 {
 120         unsigned long flags;
 121         long ret;
 122
 123         if (!clk->set_rate)
 124                 return -ENOSYS;
 125
 126         spin_lock_irqsave(&clk_lock, flags);
 127         ret = clk->set_rate(clk, rate, 1);
 128         spin_unlock_irqrestore(&clk_lock, flags);
 129
 130         return (ret < 0) ? ret : 0;
 131 }
 132 EXPORT_SYMBOL(clk_set_rate);
 133
 134 int clk_set_parent(struct clk *clk, struct clk *parent)
 135 {
 136         unsigned long flags;
 137         int ret;
 138
 139         if (!clk->set_parent)
 140                 return -ENOSYS;
 141
 142         spin_lock_irqsave(&clk_lock, flags);
 143         ret = clk->set_parent(clk, parent);
 144         spin_unlock_irqrestore(&clk_lock, flags);
 145
 146         return ret;
 147 }
 148 EXPORT_SYMBOL(clk_set_parent);
 149
 150 struct clk *clk_get_parent(struct clk *clk)
 151 {
 152         return clk->parent;
 153 }
 154 EXPORT_SYMBOL(clk_get_parent);
 155
 156
 157
 158 #ifdef CONFIG_DEBUG_FS
 159
 160 /* /sys/kernel/debug/at32ap_clk */
 161
 162 #include <linux/io.h>
 163 #include <linux/debugfs.h>
 164 #include <linux/seq_file.h>
 165 #include "pm.h"
 166
 167
 168 #define NEST_DELTA      2
 169 #define NEST_MAX        6
 170
 171 struct clkinf {
 172         struct seq_file *s;
 173         unsigned        nest;
 174 };
 175
 176 static void
 177 dump_clock(struct clk *parent, struct clkinf *r)
 178 {
 179         unsigned        nest = r->nest;
 180         char            buf[16 + NEST_MAX];
 181         struct clk      *clk;
 182         unsigned        i;
 183
 184         /* skip clocks coupled to devices that aren't registered */
 185         if (parent->dev && !parent->dev->bus_id[0] && !parent->users)
 186                 return;
 187
 188         /* <nest spaces> name <pad to end> */
 189         memset(buf, ' ', sizeof(buf) - 1);
 190         buf[sizeof(buf) - 1] = 0;
 191         i = strlen(parent->name);
 192         memcpy(buf + nest, parent->name,
 193                         min(i, (unsigned)(sizeof(buf) - 1 - nest)));
 194
 195         seq_printf(r->s, "%s%c users=%2d %-3s %9ld Hz",
 196                 buf, parent->set_parent ? '*' : ' ',
 197                 parent->users,
 198                 parent->users ? "on" : "off",   /* NOTE: not-paranoid!! */
 199                 clk_get_rate(parent));
 200         if (parent->dev)
 201                 seq_printf(r->s, ", for %s", parent->dev->bus_id);
 202         seq_printf(r->s, "\n");
 203
 204         /* cost of this scan is small, but not linear... */
 205         r->nest = nest + NEST_DELTA;
 206         for (i = 3; i < at32_nr_clocks; i++) {
 207                 clk = at32_clock_list[i];
 208                 if (clk->parent == parent)
 209                         dump_clock(clk, r);
 210         }
 211         r->nest = nest;
 212 }
 213
 214 static int clk_show(struct seq_file *s, void *unused)
 215 {
 216         struct clkinf   r;
 217         int             i;
 218
 219         /* show all the power manager registers */
 220         seq_printf(s, "MCCTRL  = %8x\n", pm_readl(MCCTRL));
 221         seq_printf(s, "CKSEL   = %8x\n", pm_readl(CKSEL));
 222         seq_printf(s, "CPUMASK = %8x\n", pm_readl(CPU_MASK));
 223         seq_printf(s, "HSBMASK = %8x\n", pm_readl(HSB_MASK));
 224         seq_printf(s, "PBAMASK = %8x\n", pm_readl(PBA_MASK));
 225         seq_printf(s, "PBBMASK = %8x\n", pm_readl(PBB_MASK));
 226         seq_printf(s, "PLL0    = %8x\n", pm_readl(PLL0));
 227         seq_printf(s, "PLL1    = %8x\n", pm_readl(PLL1));
 228         seq_printf(s, "IMR     = %8x\n", pm_readl(IMR));
 229         for (i = 0; i < 8; i++) {
 230                 if (i == 5)
 231                         continue;
 232                 seq_printf(s, "GCCTRL%d = %8x\n", i, pm_readl(GCCTRL(i)));
 233         }
 234
 235         seq_printf(s, "\n");
 236
 237         /* show clock tree as derived from the three oscillators
 238          * we "know" are at the head of the list
 239          */
 240         r.s = s;
 241         r.nest = 0;
 242         dump_clock(at32_clock_list[0], &r);
 243         dump_clock(at32_clock_list[1], &r);
 244         dump_clock(at32_clock_list[2], &r);
 245
 246         return 0;
 247 }
 248
 249 static int clk_open(struct inode *inode, struct file *file)
 250 {
 251         return single_open(file, clk_show, NULL);
 252 }
 253
 254 static const struct file_operations clk_operations = {
 255         .open           = clk_open,
 256         .read           = seq_read,
 257         .llseek         = seq_lseek,
 258         .release        = single_release,
 259 };
 260
 261 static int __init clk_debugfs_init(void)
 262 {
 263         (void) debugfs_create_file("at32ap_clk", S_IFREG | S_IRUGO,
 264                         NULL, NULL, &clk_operations);
 265
 266         return 0;
 267 }
 268 postcore_initcall(clk_debugfs_init);
 269
 270 #endif