1 /*
2  * Copyright 2013 Broadcom Corporation.
3  *
4  * SPDX-License-Identifier:      GPL-2.0+
5  */
6 
7 #include <linux/stddef.h>
8 
9 #ifdef CONFIG_CLK_DEBUG
10 #undef writel
11 #undef readl
12 static inline void writel(u32 val, void *addr)
13 {
14 	printf("Write [0x%p] = 0x%08x\n", addr, val);
15 	*(u32 *)addr = val;
16 }
17 
18 static inline u32 readl(void *addr)
19 {
20 	u32 val = *(u32 *)addr;
21 	printf("Read  [0x%p] = 0x%08x\n", addr, val);
22 	return val;
23 }
24 #endif
25 
26 struct clk;
27 
28 struct clk_lookup {
29 	const char *dev_id;
30 	const char *con_id;
31 	struct clk *clk;
32 };
33 
34 extern struct clk_lookup arch_clk_tbl[];
35 extern unsigned int arch_clk_tbl_array_size;
36 
37 /**
38  * struct clk_ops - standard clock operations
39  * @enable: enable/disable clock, see clk_enable() and clk_disable()
40  * @set_rate: set the clock rate, see clk_set_rate().
41  * @get_rate: get the clock rate, see clk_get_rate().
42  * @round_rate: round a given clock rate, see clk_round_rate().
43  * @set_parent: set the clock's parent, see clk_set_parent().
44  *
45  * Group the common clock implementations together so that we
46  * don't have to keep setting the same fiels again. We leave
47  * enable in struct clk.
48  *
49  */
50 struct clk_ops {
51 	int (*enable) (struct clk *c, int enable);
52 	int (*set_rate) (struct clk *c, unsigned long rate);
53 	unsigned long (*get_rate) (struct clk *c);
54 	unsigned long (*round_rate) (struct clk *c, unsigned long rate);
55 	int (*set_parent) (struct clk *c, struct clk *parent);
56 };
57 
58 struct clk {
59 	struct clk *parent;
60 	const char *name;
61 	int use_cnt;
62 	unsigned long rate;	/* in HZ */
63 
64 	/* programmable divider. 0 means fixed ratio to parent clock */
65 	unsigned long div;
66 
67 	struct clk_src *src;
68 	struct clk_ops *ops;
69 
70 	unsigned long ccu_clk_mgr_base;
71 	int sel;
72 };
73 
74 struct refclk *refclk_str_to_clk(const char *name);
75 
76 #define U8_MAX	((u8)~0U)
77 #define U32_MAX	((u32)~0U)
78 #define U64_MAX	((u64)~0U)
79 
80 /* The common clock framework uses u8 to represent a parent index */
81 #define PARENT_COUNT_MAX	((u32)U8_MAX)
82 
83 #define BAD_CLK_INDEX		U8_MAX	/* Can't ever be valid */
84 #define BAD_CLK_NAME		((const char *)-1)
85 
86 #define BAD_SCALED_DIV_VALUE	U64_MAX
87 
88 /*
89  * Utility macros for object flag management.  If possible, flags
90  * should be defined such that 0 is the desired default value.
91  */
92 #define FLAG(type, flag)		BCM_CLK_ ## type ## _FLAGS_ ## flag
93 #define FLAG_SET(obj, type, flag)	((obj)->flags |= FLAG(type, flag))
94 #define FLAG_CLEAR(obj, type, flag)	((obj)->flags &= ~(FLAG(type, flag)))
95 #define FLAG_FLIP(obj, type, flag)	((obj)->flags ^= FLAG(type, flag))
96 #define FLAG_TEST(obj, type, flag)	(!!((obj)->flags & FLAG(type, flag)))
97 
98 /* Clock field state tests */
99 
100 #define gate_exists(gate)		FLAG_TEST(gate, GATE, EXISTS)
101 #define gate_is_enabled(gate)		FLAG_TEST(gate, GATE, ENABLED)
102 #define gate_is_hw_controllable(gate)	FLAG_TEST(gate, GATE, HW)
103 #define gate_is_sw_controllable(gate)	FLAG_TEST(gate, GATE, SW)
104 #define gate_is_sw_managed(gate)	FLAG_TEST(gate, GATE, SW_MANAGED)
105 #define gate_is_no_disable(gate)	FLAG_TEST(gate, GATE, NO_DISABLE)
106 
107 #define gate_flip_enabled(gate)		FLAG_FLIP(gate, GATE, ENABLED)
108 
109 #define divider_exists(div)		FLAG_TEST(div, DIV, EXISTS)
110 #define divider_is_fixed(div)		FLAG_TEST(div, DIV, FIXED)
111 #define divider_has_fraction(div)	(!divider_is_fixed(div) && \
112 						(div)->frac_width > 0)
113 
114 #define selector_exists(sel)		((sel)->width != 0)
115 #define trigger_exists(trig)		FLAG_TEST(trig, TRIG, EXISTS)
116 
117 /* Clock type, used to tell common block what it's part of */
118 enum bcm_clk_type {
119 	bcm_clk_none,		/* undefined clock type */
120 	bcm_clk_bus,
121 	bcm_clk_core,
122 	bcm_clk_peri
123 };
124 
125 /*
126  * Gating control and status is managed by a 32-bit gate register.
127  *
128  * There are several types of gating available:
129  * - (no gate)
130  *     A clock with no gate is assumed to be always enabled.
131  * - hardware-only gating (auto-gating)
132  *     Enabling or disabling clocks with this type of gate is
133  *     managed automatically by the hardware.  Such clocks can be
134  *     considered by the software to be enabled.  The current status
135  *     of auto-gated clocks can be read from the gate status bit.
136  * - software-only gating
137  *     Auto-gating is not available for this type of clock.
138  *     Instead, software manages whether it's enabled by setting or
139  *     clearing the enable bit.  The current gate status of a gate
140  *     under software control can be read from the gate status bit.
141  *     To ensure a change to the gating status is complete, the
142  *     status bit can be polled to verify that the gate has entered
143  *     the desired state.
144  * - selectable hardware or software gating
145  *     Gating for this type of clock can be configured to be either
146  *     under software or hardware control.  Which type is in use is
147  *     determined by the hw_sw_sel bit of the gate register.
148  */
149 struct bcm_clk_gate {
150 	u32 offset;		/* gate register offset */
151 	u32 status_bit;		/* 0: gate is disabled; 0: gatge is enabled */
152 	u32 en_bit;		/* 0: disable; 1: enable */
153 	u32 hw_sw_sel_bit;	/* 0: hardware gating; 1: software gating */
154 	u32 flags;		/* BCM_CLK_GATE_FLAGS_* below */
155 };
156 
157 /*
158  * Gate flags:
159  *   HW         means this gate can be auto-gated
160  *   SW         means the state of this gate can be software controlled
161  *   NO_DISABLE means this gate is (only) enabled if under software control
162  *   SW_MANAGED means the status of this gate is under software control
163  *   ENABLED    means this software-managed gate is *supposed* to be enabled
164  */
165 #define BCM_CLK_GATE_FLAGS_EXISTS	((u32)1 << 0)	/* Gate is valid */
166 #define BCM_CLK_GATE_FLAGS_HW		((u32)1 << 1)	/* Can auto-gate */
167 #define BCM_CLK_GATE_FLAGS_SW		((u32)1 << 2)	/* Software control */
168 #define BCM_CLK_GATE_FLAGS_NO_DISABLE	((u32)1 << 3)	/* HW or enabled */
169 #define BCM_CLK_GATE_FLAGS_SW_MANAGED	((u32)1 << 4)	/* SW now in control */
170 #define BCM_CLK_GATE_FLAGS_ENABLED	((u32)1 << 5)	/* If SW_MANAGED */
171 
172 /*
173  * Gate initialization macros.
174  *
175  * Any gate initially under software control will be enabled.
176  */
177 
178 /* A hardware/software gate initially under software control */
179 #define HW_SW_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit)	\
180 	{								\
181 		.offset = (_offset),					\
182 		.status_bit = (_status_bit),				\
183 		.en_bit = (_en_bit),					\
184 		.hw_sw_sel_bit = (_hw_sw_sel_bit),			\
185 		.flags = FLAG(GATE, HW)|FLAG(GATE, SW)|			\
186 			FLAG(GATE, SW_MANAGED)|FLAG(GATE, ENABLED)|	\
187 			FLAG(GATE, EXISTS),				\
188 	}
189 
190 /* A hardware/software gate initially under hardware control */
191 #define HW_SW_GATE_AUTO(_offset, _status_bit, _en_bit, _hw_sw_sel_bit)	\
192 	{								\
193 		.offset = (_offset),					\
194 		.status_bit = (_status_bit),				\
195 		.en_bit = (_en_bit),					\
196 		.hw_sw_sel_bit = (_hw_sw_sel_bit),			\
197 		.flags = FLAG(GATE, HW)|FLAG(GATE, SW)|			\
198 			FLAG(GATE, EXISTS),				\
199 	}
200 
201 /* A hardware-or-enabled gate (enabled if not under hardware control) */
202 #define HW_ENABLE_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit)	\
203 	{								\
204 		.offset = (_offset),					\
205 		.status_bit = (_status_bit),				\
206 		.en_bit = (_en_bit),					\
207 		.hw_sw_sel_bit = (_hw_sw_sel_bit),			\
208 		.flags = FLAG(GATE, HW)|FLAG(GATE, SW)|			\
209 			FLAG(GATE, NO_DISABLE)|FLAG(GATE, EXISTS),	\
210 	}
211 
212 /* A software-only gate */
213 #define SW_ONLY_GATE(_offset, _status_bit, _en_bit)			\
214 	{								\
215 		.offset = (_offset),					\
216 		.status_bit = (_status_bit),				\
217 		.en_bit = (_en_bit),					\
218 		.flags = FLAG(GATE, SW)|FLAG(GATE, SW_MANAGED)|		\
219 			FLAG(GATE, ENABLED)|FLAG(GATE, EXISTS),		\
220 	}
221 
222 /* A hardware-only gate */
223 #define HW_ONLY_GATE(_offset, _status_bit)				\
224 	{								\
225 		.offset = (_offset),					\
226 		.status_bit = (_status_bit),				\
227 		.flags = FLAG(GATE, HW)|FLAG(GATE, EXISTS),		\
228 	}
229 
230 /*
231  * Each clock can have zero, one, or two dividers which change the
232  * output rate of the clock.  Each divider can be either fixed or
233  * variable.  If there are two dividers, they are the "pre-divider"
234  * and the "regular" or "downstream" divider.  If there is only one,
235  * there is no pre-divider.
236  *
237  * A fixed divider is any non-zero (positive) value, and it
238  * indicates how the input rate is affected by the divider.
239  *
240  * The value of a variable divider is maintained in a sub-field of a
241  * 32-bit divider register.  The position of the field in the
242  * register is defined by its offset and width.  The value recorded
243  * in this field is always 1 less than the value it represents.
244  *
245  * In addition, a variable divider can indicate that some subset
246  * of its bits represent a "fractional" part of the divider.  Such
247  * bits comprise the low-order portion of the divider field, and can
248  * be viewed as representing the portion of the divider that lies to
249  * the right of the decimal point.  Most variable dividers have zero
250  * fractional bits.  Variable dividers with non-zero fraction width
251  * still record a value 1 less than the value they represent; the
252  * added 1 does *not* affect the low-order bit in this case, it
253  * affects the bits above the fractional part only.  (Often in this
254  * code a divider field value is distinguished from the value it
255  * represents by referring to the latter as a "divisor".)
256  *
257  * In order to avoid dealing with fractions, divider arithmetic is
258  * performed using "scaled" values.  A scaled value is one that's
259  * been left-shifted by the fractional width of a divider.  Dividing
260  * a scaled value by a scaled divisor produces the desired quotient
261  * without loss of precision and without any other special handling
262  * for fractions.
263  *
264  * The recorded value of a variable divider can be modified.  To
265  * modify either divider (or both), a clock must be enabled (i.e.,
266  * using its gate).  In addition, a trigger register (described
267  * below) must be used to commit the change, and polled to verify
268  * the change is complete.
269  */
270 struct bcm_clk_div {
271 	union {
272 		struct {	/* variable divider */
273 			u32 offset;	/* divider register offset */
274 			u32 shift;	/* field shift */
275 			u32 width;	/* field width */
276 			u32 frac_width;	/* field fraction width */
277 
278 			u64 scaled_div;	/* scaled divider value */
279 		};
280 		u32 fixed;	/* non-zero fixed divider value */
281 	};
282 	u32 flags;		/* BCM_CLK_DIV_FLAGS_* below */
283 };
284 
285 /*
286  * Divider flags:
287  *   EXISTS means this divider exists
288  *   FIXED means it is a fixed-rate divider
289  */
290 #define BCM_CLK_DIV_FLAGS_EXISTS	((u32)1 << 0)	/* Divider is valid */
291 #define BCM_CLK_DIV_FLAGS_FIXED		((u32)1 << 1)	/* Fixed-value */
292 
293 /* Divider initialization macros */
294 
295 /* A fixed (non-zero) divider */
296 #define FIXED_DIVIDER(_value)						\
297 	{								\
298 		.fixed = (_value),					\
299 		.flags = FLAG(DIV, EXISTS)|FLAG(DIV, FIXED),		\
300 	}
301 
302 /* A divider with an integral divisor */
303 #define DIVIDER(_offset, _shift, _width)				\
304 	{								\
305 		.offset = (_offset),					\
306 		.shift = (_shift),					\
307 		.width = (_width),					\
308 		.scaled_div = BAD_SCALED_DIV_VALUE,			\
309 		.flags = FLAG(DIV, EXISTS),				\
310 	}
311 
312 /* A divider whose divisor has an integer and fractional part */
313 #define FRAC_DIVIDER(_offset, _shift, _width, _frac_width)		\
314 	{								\
315 		.offset = (_offset),					\
316 		.shift = (_shift),					\
317 		.width = (_width),					\
318 		.frac_width = (_frac_width),				\
319 		.scaled_div = BAD_SCALED_DIV_VALUE,			\
320 		.flags = FLAG(DIV, EXISTS),				\
321 	}
322 
323 /*
324  * Clocks may have multiple "parent" clocks.  If there is more than
325  * one, a selector must be specified to define which of the parent
326  * clocks is currently in use.  The selected clock is indicated in a
327  * sub-field of a 32-bit selector register.  The range of
328  * representable selector values typically exceeds the number of
329  * available parent clocks.  Occasionally the reset value of a
330  * selector field is explicitly set to a (specific) value that does
331  * not correspond to a defined input clock.
332  *
333  * We register all known parent clocks with the common clock code
334  * using a packed array (i.e., no empty slots) of (parent) clock
335  * names, and refer to them later using indexes into that array.
336  * We maintain an array of selector values indexed by common clock
337  * index values in order to map between these common clock indexes
338  * and the selector values used by the hardware.
339  *
340  * Like dividers, a selector can be modified, but to do so a clock
341  * must be enabled, and a trigger must be used to commit the change.
342  */
343 struct bcm_clk_sel {
344 	u32 offset;		/* selector register offset */
345 	u32 shift;		/* field shift */
346 	u32 width;		/* field width */
347 
348 	u32 parent_count;	/* number of entries in parent_sel[] */
349 	u32 *parent_sel;	/* array of parent selector values */
350 	u8 clk_index;		/* current selected index in parent_sel[] */
351 };
352 
353 /* Selector initialization macro */
354 #define SELECTOR(_offset, _shift, _width)				\
355 	{								\
356 		.offset = (_offset),					\
357 		.shift = (_shift),					\
358 		.width = (_width),					\
359 		.clk_index = BAD_CLK_INDEX,				\
360 	}
361 
362 /*
363  * Making changes to a variable divider or a selector for a clock
364  * requires the use of a trigger.  A trigger is defined by a single
365  * bit within a register.  To signal a change, a 1 is written into
366  * that bit.  To determine when the change has been completed, that
367  * trigger bit is polled; the read value will be 1 while the change
368  * is in progress, and 0 when it is complete.
369  *
370  * Occasionally a clock will have more than one trigger.  In this
371  * case, the "pre-trigger" will be used when changing a clock's
372  * selector and/or its pre-divider.
373  */
374 struct bcm_clk_trig {
375 	u32 offset;		/* trigger register offset */
376 	u32 bit;		/* trigger bit */
377 	u32 flags;		/* BCM_CLK_TRIG_FLAGS_* below */
378 };
379 
380 /*
381  * Trigger flags:
382  *   EXISTS means this trigger exists
383  */
384 #define BCM_CLK_TRIG_FLAGS_EXISTS	((u32)1 << 0)	/* Trigger is valid */
385 
386 /* Trigger initialization macro */
387 #define TRIGGER(_offset, _bit)						\
388 	{								\
389 		.offset = (_offset),					\
390 		.bit = (_bit),						\
391 		.flags = FLAG(TRIG, EXISTS),				\
392 	}
393 
394 struct bus_clk_data {
395 	struct bcm_clk_gate gate;
396 };
397 
398 struct core_clk_data {
399 	struct bcm_clk_gate gate;
400 };
401 
402 struct peri_clk_data {
403 	struct bcm_clk_gate gate;
404 	struct bcm_clk_trig pre_trig;
405 	struct bcm_clk_div pre_div;
406 	struct bcm_clk_trig trig;
407 	struct bcm_clk_div div;
408 	struct bcm_clk_sel sel;
409 	const char *clocks[];	/* must be last; use CLOCKS() to declare */
410 };
411 #define CLOCKS(...)	{ __VA_ARGS__, NULL, }
412 #define NO_CLOCKS	{ NULL, }	/* Must use of no parent clocks */
413 
414 struct refclk {
415 	struct clk clk;
416 };
417 
418 struct peri_clock {
419 	struct clk clk;
420 	struct peri_clk_data *data;
421 };
422 
423 struct ccu_clock {
424 	struct clk clk;
425 
426 	int num_policy_masks;
427 	unsigned long policy_freq_offset;
428 	int freq_bit_shift;	/* 8 for most CCUs */
429 	unsigned long policy_ctl_offset;
430 	unsigned long policy0_mask_offset;
431 	unsigned long policy1_mask_offset;
432 	unsigned long policy2_mask_offset;
433 	unsigned long policy3_mask_offset;
434 	unsigned long policy0_mask2_offset;
435 	unsigned long policy1_mask2_offset;
436 	unsigned long policy2_mask2_offset;
437 	unsigned long policy3_mask2_offset;
438 	unsigned long lvm_en_offset;
439 
440 	int freq_id;
441 	unsigned long *freq_tbl;
442 };
443 
444 struct bus_clock {
445 	struct clk clk;
446 	struct bus_clk_data *data;
447 	unsigned long *freq_tbl;
448 };
449 
450 struct ref_clock {
451 	struct clk clk;
452 };
453 
454 static inline int is_same_clock(struct clk *a, struct clk *b)
455 {
456 	return (a == b);
457 }
458 
459 #define to_clk(p) (&((p)->clk))
460 #define name_to_clk(name) (&((name##_clk).clk))
461 /* declare a struct clk_lookup */
462 #define CLK_LK(name) \
463 {.con_id = __stringify(name##_clk), .clk = name_to_clk(name),}
464 
465 static inline struct refclk *to_refclk(struct clk *clock)
466 {
467 	return container_of(clock, struct refclk, clk);
468 }
469 
470 static inline struct peri_clock *to_peri_clk(struct clk *clock)
471 {
472 	return container_of(clock, struct peri_clock, clk);
473 }
474 
475 static inline struct ccu_clock *to_ccu_clk(struct clk *clock)
476 {
477 	return container_of(clock, struct ccu_clock, clk);
478 }
479 
480 static inline struct bus_clock *to_bus_clk(struct clk *clock)
481 {
482 	return container_of(clock, struct bus_clock, clk);
483 }
484 
485 static inline struct ref_clock *to_ref_clk(struct clk *clock)
486 {
487 	return container_of(clock, struct ref_clock, clk);
488 }
489 
490 extern struct clk_ops peri_clk_ops;
491 extern struct clk_ops ccu_clk_ops;
492 extern struct clk_ops bus_clk_ops;
493 extern struct clk_ops ref_clk_ops;
494 
495 extern int clk_get_and_enable(char *clkstr);
496