Commit | Line | Data |
---|---|---|
1f27f152 AE |
1 | /* |
2 | * Copyright (C) 2013 Broadcom Corporation | |
3 | * Copyright 2013 Linaro Limited | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU General Public License as | |
7 | * published by the Free Software Foundation version 2. | |
8 | * | |
9 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | |
10 | * kind, whether express or implied; without even the implied warranty | |
11 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | */ | |
14 | ||
15 | #ifndef _CLK_KONA_H | |
16 | #define _CLK_KONA_H | |
17 | ||
18 | #include <linux/kernel.h> | |
19 | #include <linux/list.h> | |
20 | #include <linux/spinlock.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/device.h> | |
23 | #include <linux/of.h> | |
24 | #include <linux/clk-provider.h> | |
25 | ||
26 | #define BILLION 1000000000 | |
27 | ||
28 | /* The common clock framework uses u8 to represent a parent index */ | |
29 | #define PARENT_COUNT_MAX ((u32)U8_MAX) | |
30 | ||
31 | #define BAD_CLK_INDEX U8_MAX /* Can't ever be valid */ | |
32 | #define BAD_CLK_NAME ((const char *)-1) | |
33 | ||
34 | #define BAD_SCALED_DIV_VALUE U64_MAX | |
35 | ||
36 | /* | |
37 | * Utility macros for object flag management. If possible, flags | |
38 | * should be defined such that 0 is the desired default value. | |
39 | */ | |
40 | #define FLAG(type, flag) BCM_CLK_ ## type ## _FLAGS_ ## flag | |
41 | #define FLAG_SET(obj, type, flag) ((obj)->flags |= FLAG(type, flag)) | |
42 | #define FLAG_CLEAR(obj, type, flag) ((obj)->flags &= ~(FLAG(type, flag))) | |
43 | #define FLAG_FLIP(obj, type, flag) ((obj)->flags ^= FLAG(type, flag)) | |
44 | #define FLAG_TEST(obj, type, flag) (!!((obj)->flags & FLAG(type, flag))) | |
45 | ||
46 | /* Clock field state tests */ | |
47 | ||
48 | #define gate_exists(gate) FLAG_TEST(gate, GATE, EXISTS) | |
49 | #define gate_is_enabled(gate) FLAG_TEST(gate, GATE, ENABLED) | |
50 | #define gate_is_hw_controllable(gate) FLAG_TEST(gate, GATE, HW) | |
51 | #define gate_is_sw_controllable(gate) FLAG_TEST(gate, GATE, SW) | |
52 | #define gate_is_sw_managed(gate) FLAG_TEST(gate, GATE, SW_MANAGED) | |
53 | #define gate_is_no_disable(gate) FLAG_TEST(gate, GATE, NO_DISABLE) | |
54 | ||
55 | #define gate_flip_enabled(gate) FLAG_FLIP(gate, GATE, ENABLED) | |
56 | ||
57 | #define divider_exists(div) FLAG_TEST(div, DIV, EXISTS) | |
58 | #define divider_is_fixed(div) FLAG_TEST(div, DIV, FIXED) | |
59 | #define divider_has_fraction(div) (!divider_is_fixed(div) && \ | |
e813d49d | 60 | (div)->u.s.frac_width > 0) |
1f27f152 AE |
61 | |
62 | #define selector_exists(sel) ((sel)->width != 0) | |
63 | #define trigger_exists(trig) FLAG_TEST(trig, TRIG, EXISTS) | |
64 | ||
65 | /* Clock type, used to tell common block what it's part of */ | |
66 | enum bcm_clk_type { | |
67 | bcm_clk_none, /* undefined clock type */ | |
68 | bcm_clk_bus, | |
69 | bcm_clk_core, | |
70 | bcm_clk_peri | |
71 | }; | |
72 | ||
73 | /* | |
74 | * Each CCU defines a mapped area of memory containing registers | |
75 | * used to manage clocks implemented by the CCU. Access to memory | |
76 | * within the CCU's space is serialized by a spinlock. Before any | |
77 | * (other) address can be written, a special access "password" value | |
78 | * must be written to its WR_ACCESS register (located at the base | |
79 | * address of the range). We keep track of the name of each CCU as | |
80 | * it is set up, and maintain them in a list. | |
81 | */ | |
82 | struct ccu_data { | |
83 | void __iomem *base; /* base of mapped address space */ | |
84 | spinlock_t lock; /* serialization lock */ | |
85 | bool write_enabled; /* write access is currently enabled */ | |
86 | struct list_head links; /* for ccu_list */ | |
87 | struct device_node *node; | |
88 | struct clk_onecell_data data; | |
89 | const char *name; | |
90 | u32 range; /* byte range of address space */ | |
91 | }; | |
92 | ||
93 | /* | |
94 | * Gating control and status is managed by a 32-bit gate register. | |
95 | * | |
96 | * There are several types of gating available: | |
97 | * - (no gate) | |
98 | * A clock with no gate is assumed to be always enabled. | |
99 | * - hardware-only gating (auto-gating) | |
100 | * Enabling or disabling clocks with this type of gate is | |
101 | * managed automatically by the hardware. Such clocks can be | |
102 | * considered by the software to be enabled. The current status | |
103 | * of auto-gated clocks can be read from the gate status bit. | |
104 | * - software-only gating | |
105 | * Auto-gating is not available for this type of clock. | |
106 | * Instead, software manages whether it's enabled by setting or | |
107 | * clearing the enable bit. The current gate status of a gate | |
108 | * under software control can be read from the gate status bit. | |
109 | * To ensure a change to the gating status is complete, the | |
110 | * status bit can be polled to verify that the gate has entered | |
111 | * the desired state. | |
112 | * - selectable hardware or software gating | |
113 | * Gating for this type of clock can be configured to be either | |
114 | * under software or hardware control. Which type is in use is | |
115 | * determined by the hw_sw_sel bit of the gate register. | |
116 | */ | |
117 | struct bcm_clk_gate { | |
118 | u32 offset; /* gate register offset */ | |
119 | u32 status_bit; /* 0: gate is disabled; 0: gatge is enabled */ | |
120 | u32 en_bit; /* 0: disable; 1: enable */ | |
121 | u32 hw_sw_sel_bit; /* 0: hardware gating; 1: software gating */ | |
122 | u32 flags; /* BCM_CLK_GATE_FLAGS_* below */ | |
123 | }; | |
124 | ||
125 | /* | |
126 | * Gate flags: | |
127 | * HW means this gate can be auto-gated | |
128 | * SW means the state of this gate can be software controlled | |
129 | * NO_DISABLE means this gate is (only) enabled if under software control | |
130 | * SW_MANAGED means the status of this gate is under software control | |
131 | * ENABLED means this software-managed gate is *supposed* to be enabled | |
132 | */ | |
133 | #define BCM_CLK_GATE_FLAGS_EXISTS ((u32)1 << 0) /* Gate is valid */ | |
134 | #define BCM_CLK_GATE_FLAGS_HW ((u32)1 << 1) /* Can auto-gate */ | |
135 | #define BCM_CLK_GATE_FLAGS_SW ((u32)1 << 2) /* Software control */ | |
136 | #define BCM_CLK_GATE_FLAGS_NO_DISABLE ((u32)1 << 3) /* HW or enabled */ | |
137 | #define BCM_CLK_GATE_FLAGS_SW_MANAGED ((u32)1 << 4) /* SW now in control */ | |
138 | #define BCM_CLK_GATE_FLAGS_ENABLED ((u32)1 << 5) /* If SW_MANAGED */ | |
139 | ||
140 | /* | |
141 | * Gate initialization macros. | |
142 | * | |
143 | * Any gate initially under software control will be enabled. | |
144 | */ | |
145 | ||
146 | /* A hardware/software gate initially under software control */ | |
147 | #define HW_SW_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \ | |
148 | { \ | |
149 | .offset = (_offset), \ | |
150 | .status_bit = (_status_bit), \ | |
151 | .en_bit = (_en_bit), \ | |
152 | .hw_sw_sel_bit = (_hw_sw_sel_bit), \ | |
153 | .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \ | |
154 | FLAG(GATE, SW_MANAGED)|FLAG(GATE, ENABLED)| \ | |
155 | FLAG(GATE, EXISTS), \ | |
156 | } | |
157 | ||
158 | /* A hardware/software gate initially under hardware control */ | |
159 | #define HW_SW_GATE_AUTO(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \ | |
160 | { \ | |
161 | .offset = (_offset), \ | |
162 | .status_bit = (_status_bit), \ | |
163 | .en_bit = (_en_bit), \ | |
164 | .hw_sw_sel_bit = (_hw_sw_sel_bit), \ | |
165 | .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \ | |
166 | FLAG(GATE, EXISTS), \ | |
167 | } | |
168 | ||
169 | /* A hardware-or-enabled gate (enabled if not under hardware control) */ | |
170 | #define HW_ENABLE_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \ | |
171 | { \ | |
172 | .offset = (_offset), \ | |
173 | .status_bit = (_status_bit), \ | |
174 | .en_bit = (_en_bit), \ | |
175 | .hw_sw_sel_bit = (_hw_sw_sel_bit), \ | |
176 | .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \ | |
177 | FLAG(GATE, NO_DISABLE)|FLAG(GATE, EXISTS), \ | |
178 | } | |
179 | ||
180 | /* A software-only gate */ | |
181 | #define SW_ONLY_GATE(_offset, _status_bit, _en_bit) \ | |
182 | { \ | |
183 | .offset = (_offset), \ | |
184 | .status_bit = (_status_bit), \ | |
185 | .en_bit = (_en_bit), \ | |
186 | .flags = FLAG(GATE, SW)|FLAG(GATE, SW_MANAGED)| \ | |
187 | FLAG(GATE, ENABLED)|FLAG(GATE, EXISTS), \ | |
188 | } | |
189 | ||
190 | /* A hardware-only gate */ | |
191 | #define HW_ONLY_GATE(_offset, _status_bit) \ | |
192 | { \ | |
193 | .offset = (_offset), \ | |
194 | .status_bit = (_status_bit), \ | |
195 | .flags = FLAG(GATE, HW)|FLAG(GATE, EXISTS), \ | |
196 | } | |
197 | ||
198 | /* | |
199 | * Each clock can have zero, one, or two dividers which change the | |
200 | * output rate of the clock. Each divider can be either fixed or | |
201 | * variable. If there are two dividers, they are the "pre-divider" | |
202 | * and the "regular" or "downstream" divider. If there is only one, | |
203 | * there is no pre-divider. | |
204 | * | |
205 | * A fixed divider is any non-zero (positive) value, and it | |
206 | * indicates how the input rate is affected by the divider. | |
207 | * | |
208 | * The value of a variable divider is maintained in a sub-field of a | |
209 | * 32-bit divider register. The position of the field in the | |
210 | * register is defined by its offset and width. The value recorded | |
211 | * in this field is always 1 less than the value it represents. | |
212 | * | |
213 | * In addition, a variable divider can indicate that some subset | |
214 | * of its bits represent a "fractional" part of the divider. Such | |
215 | * bits comprise the low-order portion of the divider field, and can | |
216 | * be viewed as representing the portion of the divider that lies to | |
217 | * the right of the decimal point. Most variable dividers have zero | |
218 | * fractional bits. Variable dividers with non-zero fraction width | |
219 | * still record a value 1 less than the value they represent; the | |
220 | * added 1 does *not* affect the low-order bit in this case, it | |
221 | * affects the bits above the fractional part only. (Often in this | |
222 | * code a divider field value is distinguished from the value it | |
223 | * represents by referring to the latter as a "divisor".) | |
224 | * | |
225 | * In order to avoid dealing with fractions, divider arithmetic is | |
226 | * performed using "scaled" values. A scaled value is one that's | |
227 | * been left-shifted by the fractional width of a divider. Dividing | |
228 | * a scaled value by a scaled divisor produces the desired quotient | |
229 | * without loss of precision and without any other special handling | |
230 | * for fractions. | |
231 | * | |
232 | * The recorded value of a variable divider can be modified. To | |
233 | * modify either divider (or both), a clock must be enabled (i.e., | |
234 | * using its gate). In addition, a trigger register (described | |
235 | * below) must be used to commit the change, and polled to verify | |
236 | * the change is complete. | |
237 | */ | |
238 | struct bcm_clk_div { | |
239 | union { | |
240 | struct { /* variable divider */ | |
241 | u32 offset; /* divider register offset */ | |
242 | u32 shift; /* field shift */ | |
243 | u32 width; /* field width */ | |
244 | u32 frac_width; /* field fraction width */ | |
245 | ||
246 | u64 scaled_div; /* scaled divider value */ | |
e813d49d | 247 | } s; |
1f27f152 | 248 | u32 fixed; /* non-zero fixed divider value */ |
e813d49d | 249 | } u; |
1f27f152 AE |
250 | u32 flags; /* BCM_CLK_DIV_FLAGS_* below */ |
251 | }; | |
252 | ||
253 | /* | |
254 | * Divider flags: | |
255 | * EXISTS means this divider exists | |
256 | * FIXED means it is a fixed-rate divider | |
257 | */ | |
258 | #define BCM_CLK_DIV_FLAGS_EXISTS ((u32)1 << 0) /* Divider is valid */ | |
259 | #define BCM_CLK_DIV_FLAGS_FIXED ((u32)1 << 1) /* Fixed-value */ | |
260 | ||
261 | /* Divider initialization macros */ | |
262 | ||
263 | /* A fixed (non-zero) divider */ | |
264 | #define FIXED_DIVIDER(_value) \ | |
265 | { \ | |
e813d49d | 266 | .u.fixed = (_value), \ |
1f27f152 AE |
267 | .flags = FLAG(DIV, EXISTS)|FLAG(DIV, FIXED), \ |
268 | } | |
269 | ||
270 | /* A divider with an integral divisor */ | |
271 | #define DIVIDER(_offset, _shift, _width) \ | |
272 | { \ | |
e813d49d AE |
273 | .u.s.offset = (_offset), \ |
274 | .u.s.shift = (_shift), \ | |
275 | .u.s.width = (_width), \ | |
276 | .u.s.scaled_div = BAD_SCALED_DIV_VALUE, \ | |
1f27f152 AE |
277 | .flags = FLAG(DIV, EXISTS), \ |
278 | } | |
279 | ||
280 | /* A divider whose divisor has an integer and fractional part */ | |
281 | #define FRAC_DIVIDER(_offset, _shift, _width, _frac_width) \ | |
282 | { \ | |
e813d49d AE |
283 | .u.s.offset = (_offset), \ |
284 | .u.s.shift = (_shift), \ | |
285 | .u.s.width = (_width), \ | |
286 | .u.s.frac_width = (_frac_width), \ | |
287 | .u.s.scaled_div = BAD_SCALED_DIV_VALUE, \ | |
1f27f152 AE |
288 | .flags = FLAG(DIV, EXISTS), \ |
289 | } | |
290 | ||
291 | /* | |
292 | * Clocks may have multiple "parent" clocks. If there is more than | |
293 | * one, a selector must be specified to define which of the parent | |
294 | * clocks is currently in use. The selected clock is indicated in a | |
295 | * sub-field of a 32-bit selector register. The range of | |
296 | * representable selector values typically exceeds the number of | |
297 | * available parent clocks. Occasionally the reset value of a | |
298 | * selector field is explicitly set to a (specific) value that does | |
299 | * not correspond to a defined input clock. | |
300 | * | |
301 | * We register all known parent clocks with the common clock code | |
302 | * using a packed array (i.e., no empty slots) of (parent) clock | |
303 | * names, and refer to them later using indexes into that array. | |
304 | * We maintain an array of selector values indexed by common clock | |
305 | * index values in order to map between these common clock indexes | |
306 | * and the selector values used by the hardware. | |
307 | * | |
308 | * Like dividers, a selector can be modified, but to do so a clock | |
309 | * must be enabled, and a trigger must be used to commit the change. | |
310 | */ | |
311 | struct bcm_clk_sel { | |
312 | u32 offset; /* selector register offset */ | |
313 | u32 shift; /* field shift */ | |
314 | u32 width; /* field width */ | |
315 | ||
316 | u32 parent_count; /* number of entries in parent_sel[] */ | |
317 | u32 *parent_sel; /* array of parent selector values */ | |
318 | u8 clk_index; /* current selected index in parent_sel[] */ | |
319 | }; | |
320 | ||
321 | /* Selector initialization macro */ | |
322 | #define SELECTOR(_offset, _shift, _width) \ | |
323 | { \ | |
324 | .offset = (_offset), \ | |
325 | .shift = (_shift), \ | |
326 | .width = (_width), \ | |
327 | .clk_index = BAD_CLK_INDEX, \ | |
328 | } | |
329 | ||
330 | /* | |
331 | * Making changes to a variable divider or a selector for a clock | |
332 | * requires the use of a trigger. A trigger is defined by a single | |
333 | * bit within a register. To signal a change, a 1 is written into | |
334 | * that bit. To determine when the change has been completed, that | |
335 | * trigger bit is polled; the read value will be 1 while the change | |
336 | * is in progress, and 0 when it is complete. | |
337 | * | |
338 | * Occasionally a clock will have more than one trigger. In this | |
339 | * case, the "pre-trigger" will be used when changing a clock's | |
340 | * selector and/or its pre-divider. | |
341 | */ | |
342 | struct bcm_clk_trig { | |
343 | u32 offset; /* trigger register offset */ | |
344 | u32 bit; /* trigger bit */ | |
345 | u32 flags; /* BCM_CLK_TRIG_FLAGS_* below */ | |
346 | }; | |
347 | ||
348 | /* | |
349 | * Trigger flags: | |
350 | * EXISTS means this trigger exists | |
351 | */ | |
352 | #define BCM_CLK_TRIG_FLAGS_EXISTS ((u32)1 << 0) /* Trigger is valid */ | |
353 | ||
354 | /* Trigger initialization macro */ | |
355 | #define TRIGGER(_offset, _bit) \ | |
356 | { \ | |
357 | .offset = (_offset), \ | |
358 | .bit = (_bit), \ | |
359 | .flags = FLAG(TRIG, EXISTS), \ | |
360 | } | |
361 | ||
362 | struct peri_clk_data { | |
363 | struct bcm_clk_gate gate; | |
364 | struct bcm_clk_trig pre_trig; | |
365 | struct bcm_clk_div pre_div; | |
366 | struct bcm_clk_trig trig; | |
367 | struct bcm_clk_div div; | |
368 | struct bcm_clk_sel sel; | |
369 | const char *clocks[]; /* must be last; use CLOCKS() to declare */ | |
370 | }; | |
371 | #define CLOCKS(...) { __VA_ARGS__, NULL, } | |
372 | #define NO_CLOCKS { NULL, } /* Must use of no parent clocks */ | |
373 | ||
374 | struct kona_clk { | |
375 | struct clk_hw hw; | |
e7563252 | 376 | struct clk_init_data init_data; /* includes name of this clock */ |
1f27f152 AE |
377 | struct ccu_data *ccu; /* ccu this clock is associated with */ |
378 | enum bcm_clk_type type; | |
379 | union { | |
380 | void *data; | |
381 | struct peri_clk_data *peri; | |
e813d49d | 382 | } u; |
1f27f152 AE |
383 | }; |
384 | #define to_kona_clk(_hw) \ | |
385 | container_of(_hw, struct kona_clk, hw) | |
386 | ||
387 | /* Exported globals */ | |
388 | ||
389 | extern struct clk_ops kona_peri_clk_ops; | |
390 | ||
391 | /* Help functions */ | |
392 | ||
393 | #define PERI_CLK_SETUP(clks, ccu, id, name) \ | |
394 | clks[id] = kona_clk_setup(ccu, #name, bcm_clk_peri, &name ## _data) | |
395 | ||
396 | /* Externally visible functions */ | |
397 | ||
398 | extern u64 do_div_round_closest(u64 dividend, unsigned long divisor); | |
399 | extern u64 scaled_div_max(struct bcm_clk_div *div); | |
400 | extern u64 scaled_div_build(struct bcm_clk_div *div, u32 div_value, | |
401 | u32 billionths); | |
402 | ||
403 | extern struct clk *kona_clk_setup(struct ccu_data *ccu, const char *name, | |
404 | enum bcm_clk_type type, void *data); | |
405 | extern void __init kona_dt_ccu_setup(struct device_node *node, | |
406 | int (*ccu_clks_setup)(struct ccu_data *)); | |
407 | extern bool __init kona_ccu_init(struct ccu_data *ccu); | |
408 | ||
409 | #endif /* _CLK_KONA_H */ |