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authorTomi Valkeinen <tomi.valkeinen@ti.com>2012-09-03 02:26:33 -0400
committerTomi Valkeinen <tomi.valkeinen@ti.com>2012-09-03 02:26:33 -0400
commitc50e86ce7c2961a41f2f7aa6e4fd6c99229ba205 (patch)
tree4ea36009719bd8fc523239fe1bdccb90f0dce3ae /drivers/clk/clk-divider.c
parent14d33d384693eb6083396199de516fdef320f7af (diff)
parent4cbe5a555fa58a79b6ecbb6c531b8bab0650778d (diff)
Merge tag 'v3.6-rc4'
Merge 3.6-rc4 to get latest OMAP and device tree fixes.
Diffstat (limited to 'drivers/clk/clk-divider.c')
-rw-r--r--drivers/clk/clk-divider.c189
1 files changed, 155 insertions, 34 deletions
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index 8ea11b444528..a9204c69148d 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -30,18 +30,89 @@
30#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw) 30#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw)
31 31
32#define div_mask(d) ((1 << (d->width)) - 1) 32#define div_mask(d) ((1 << (d->width)) - 1)
33#define is_power_of_two(i) !(i & ~i)
34
35static unsigned int _get_table_maxdiv(const struct clk_div_table *table)
36{
37 unsigned int maxdiv = 0;
38 const struct clk_div_table *clkt;
39
40 for (clkt = table; clkt->div; clkt++)
41 if (clkt->div > maxdiv)
42 maxdiv = clkt->div;
43 return maxdiv;
44}
45
46static unsigned int _get_maxdiv(struct clk_divider *divider)
47{
48 if (divider->flags & CLK_DIVIDER_ONE_BASED)
49 return div_mask(divider);
50 if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
51 return 1 << div_mask(divider);
52 if (divider->table)
53 return _get_table_maxdiv(divider->table);
54 return div_mask(divider) + 1;
55}
56
57static unsigned int _get_table_div(const struct clk_div_table *table,
58 unsigned int val)
59{
60 const struct clk_div_table *clkt;
61
62 for (clkt = table; clkt->div; clkt++)
63 if (clkt->val == val)
64 return clkt->div;
65 return 0;
66}
67
68static unsigned int _get_div(struct clk_divider *divider, unsigned int val)
69{
70 if (divider->flags & CLK_DIVIDER_ONE_BASED)
71 return val;
72 if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
73 return 1 << val;
74 if (divider->table)
75 return _get_table_div(divider->table, val);
76 return val + 1;
77}
78
79static unsigned int _get_table_val(const struct clk_div_table *table,
80 unsigned int div)
81{
82 const struct clk_div_table *clkt;
83
84 for (clkt = table; clkt->div; clkt++)
85 if (clkt->div == div)
86 return clkt->val;
87 return 0;
88}
89
90static unsigned int _get_val(struct clk_divider *divider, u8 div)
91{
92 if (divider->flags & CLK_DIVIDER_ONE_BASED)
93 return div;
94 if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
95 return __ffs(div);
96 if (divider->table)
97 return _get_table_val(divider->table, div);
98 return div - 1;
99}
33 100
34static unsigned long clk_divider_recalc_rate(struct clk_hw *hw, 101static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
35 unsigned long parent_rate) 102 unsigned long parent_rate)
36{ 103{
37 struct clk_divider *divider = to_clk_divider(hw); 104 struct clk_divider *divider = to_clk_divider(hw);
38 unsigned int div; 105 unsigned int div, val;
39 106
40 div = readl(divider->reg) >> divider->shift; 107 val = readl(divider->reg) >> divider->shift;
41 div &= div_mask(divider); 108 val &= div_mask(divider);
42 109
43 if (!(divider->flags & CLK_DIVIDER_ONE_BASED)) 110 div = _get_div(divider, val);
44 div++; 111 if (!div) {
112 WARN(1, "%s: Invalid divisor for clock %s\n", __func__,
113 __clk_get_name(hw->clk));
114 return parent_rate;
115 }
45 116
46 return parent_rate / div; 117 return parent_rate / div;
47} 118}
@@ -52,6 +123,26 @@ static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
52 */ 123 */
53#define MULT_ROUND_UP(r, m) ((r) * (m) + (m) - 1) 124#define MULT_ROUND_UP(r, m) ((r) * (m) + (m) - 1)
54 125
126static bool _is_valid_table_div(const struct clk_div_table *table,
127 unsigned int div)
128{
129 const struct clk_div_table *clkt;
130
131 for (clkt = table; clkt->div; clkt++)
132 if (clkt->div == div)
133 return true;
134 return false;
135}
136
137static bool _is_valid_div(struct clk_divider *divider, unsigned int div)
138{
139 if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
140 return is_power_of_two(div);
141 if (divider->table)
142 return _is_valid_table_div(divider->table, div);
143 return true;
144}
145
55static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, 146static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
56 unsigned long *best_parent_rate) 147 unsigned long *best_parent_rate)
57{ 148{
@@ -62,10 +153,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
62 if (!rate) 153 if (!rate)
63 rate = 1; 154 rate = 1;
64 155
65 maxdiv = (1 << divider->width); 156 maxdiv = _get_maxdiv(divider);
66
67 if (divider->flags & CLK_DIVIDER_ONE_BASED)
68 maxdiv--;
69 157
70 if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) { 158 if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) {
71 parent_rate = *best_parent_rate; 159 parent_rate = *best_parent_rate;
@@ -82,6 +170,8 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
82 maxdiv = min(ULONG_MAX / rate, maxdiv); 170 maxdiv = min(ULONG_MAX / rate, maxdiv);
83 171
84 for (i = 1; i <= maxdiv; i++) { 172 for (i = 1; i <= maxdiv; i++) {
173 if (!_is_valid_div(divider, i))
174 continue;
85 parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 175 parent_rate = __clk_round_rate(__clk_get_parent(hw->clk),
86 MULT_ROUND_UP(rate, i)); 176 MULT_ROUND_UP(rate, i));
87 now = parent_rate / i; 177 now = parent_rate / i;
@@ -93,9 +183,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
93 } 183 }
94 184
95 if (!bestdiv) { 185 if (!bestdiv) {
96 bestdiv = (1 << divider->width); 186 bestdiv = _get_maxdiv(divider);
97 if (divider->flags & CLK_DIVIDER_ONE_BASED)
98 bestdiv--;
99 *best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1); 187 *best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1);
100 } 188 }
101 189
@@ -115,24 +203,22 @@ static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
115 unsigned long parent_rate) 203 unsigned long parent_rate)
116{ 204{
117 struct clk_divider *divider = to_clk_divider(hw); 205 struct clk_divider *divider = to_clk_divider(hw);
118 unsigned int div; 206 unsigned int div, value;
119 unsigned long flags = 0; 207 unsigned long flags = 0;
120 u32 val; 208 u32 val;
121 209
122 div = parent_rate / rate; 210 div = parent_rate / rate;
211 value = _get_val(divider, div);
123 212
124 if (!(divider->flags & CLK_DIVIDER_ONE_BASED)) 213 if (value > div_mask(divider))
125 div--; 214 value = div_mask(divider);
126
127 if (div > div_mask(divider))
128 div = div_mask(divider);
129 215
130 if (divider->lock) 216 if (divider->lock)
131 spin_lock_irqsave(divider->lock, flags); 217 spin_lock_irqsave(divider->lock, flags);
132 218
133 val = readl(divider->reg); 219 val = readl(divider->reg);
134 val &= ~(div_mask(divider) << divider->shift); 220 val &= ~(div_mask(divider) << divider->shift);
135 val |= div << divider->shift; 221 val |= value << divider->shift;
136 writel(val, divider->reg); 222 writel(val, divider->reg);
137 223
138 if (divider->lock) 224 if (divider->lock)
@@ -148,22 +234,11 @@ const struct clk_ops clk_divider_ops = {
148}; 234};
149EXPORT_SYMBOL_GPL(clk_divider_ops); 235EXPORT_SYMBOL_GPL(clk_divider_ops);
150 236
151/** 237static struct clk *_register_divider(struct device *dev, const char *name,
152 * clk_register_divider - register a divider clock with the clock framework
153 * @dev: device registering this clock
154 * @name: name of this clock
155 * @parent_name: name of clock's parent
156 * @flags: framework-specific flags
157 * @reg: register address to adjust divider
158 * @shift: number of bits to shift the bitfield
159 * @width: width of the bitfield
160 * @clk_divider_flags: divider-specific flags for this clock
161 * @lock: shared register lock for this clock
162 */
163struct clk *clk_register_divider(struct device *dev, const char *name,
164 const char *parent_name, unsigned long flags, 238 const char *parent_name, unsigned long flags,
165 void __iomem *reg, u8 shift, u8 width, 239 void __iomem *reg, u8 shift, u8 width,
166 u8 clk_divider_flags, spinlock_t *lock) 240 u8 clk_divider_flags, const struct clk_div_table *table,
241 spinlock_t *lock)
167{ 242{
168 struct clk_divider *div; 243 struct clk_divider *div;
169 struct clk *clk; 244 struct clk *clk;
@@ -178,7 +253,7 @@ struct clk *clk_register_divider(struct device *dev, const char *name,
178 253
179 init.name = name; 254 init.name = name;
180 init.ops = &clk_divider_ops; 255 init.ops = &clk_divider_ops;
181 init.flags = flags; 256 init.flags = flags | CLK_IS_BASIC;
182 init.parent_names = (parent_name ? &parent_name: NULL); 257 init.parent_names = (parent_name ? &parent_name: NULL);
183 init.num_parents = (parent_name ? 1 : 0); 258 init.num_parents = (parent_name ? 1 : 0);
184 259
@@ -189,6 +264,7 @@ struct clk *clk_register_divider(struct device *dev, const char *name,
189 div->flags = clk_divider_flags; 264 div->flags = clk_divider_flags;
190 div->lock = lock; 265 div->lock = lock;
191 div->hw.init = &init; 266 div->hw.init = &init;
267 div->table = table;
192 268
193 /* register the clock */ 269 /* register the clock */
194 clk = clk_register(dev, &div->hw); 270 clk = clk_register(dev, &div->hw);
@@ -198,3 +274,48 @@ struct clk *clk_register_divider(struct device *dev, const char *name,
198 274
199 return clk; 275 return clk;
200} 276}
277
278/**
279 * clk_register_divider - register a divider clock with the clock framework
280 * @dev: device registering this clock
281 * @name: name of this clock
282 * @parent_name: name of clock's parent
283 * @flags: framework-specific flags
284 * @reg: register address to adjust divider
285 * @shift: number of bits to shift the bitfield
286 * @width: width of the bitfield
287 * @clk_divider_flags: divider-specific flags for this clock
288 * @lock: shared register lock for this clock
289 */
290struct clk *clk_register_divider(struct device *dev, const char *name,
291 const char *parent_name, unsigned long flags,
292 void __iomem *reg, u8 shift, u8 width,
293 u8 clk_divider_flags, spinlock_t *lock)
294{
295 return _register_divider(dev, name, parent_name, flags, reg, shift,
296 width, clk_divider_flags, NULL, lock);
297}
298
299/**
300 * clk_register_divider_table - register a table based divider clock with
301 * the clock framework
302 * @dev: device registering this clock
303 * @name: name of this clock
304 * @parent_name: name of clock's parent
305 * @flags: framework-specific flags
306 * @reg: register address to adjust divider
307 * @shift: number of bits to shift the bitfield
308 * @width: width of the bitfield
309 * @clk_divider_flags: divider-specific flags for this clock
310 * @table: array of divider/value pairs ending with a div set to 0
311 * @lock: shared register lock for this clock
312 */
313struct clk *clk_register_divider_table(struct device *dev, const char *name,
314 const char *parent_name, unsigned long flags,
315 void __iomem *reg, u8 shift, u8 width,
316 u8 clk_divider_flags, const struct clk_div_table *table,
317 spinlock_t *lock)
318{
319 return _register_divider(dev, name, parent_name, flags, reg, shift,
320 width, clk_divider_flags, table, lock);
321}