2 * linux/arch/arm/mach-omap2/clock.c
4 * Copyright (C) 2005-2008 Texas Instruments, Inc.
5 * Copyright (C) 2004-2010 Nokia Corporation
8 * Richard Woodruff <r-woodruff2@ti.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 #include <linux/errno.h>
20 #include <linux/err.h>
21 #include <linux/delay.h>
22 #include <linux/clk.h>
24 #include <linux/bitops.h>
25 #include <trace/events/power.h>
28 #include <plat/clock.h>
29 #include "clockdomain.h"
31 #include <plat/prcm.h>
34 #include "cm2xxx_3xxx.h"
35 #include "cm-regbits-24xx.h"
36 #include "cm-regbits-34xx.h"
41 * clkdm_control: if true, then when a clock is enabled in the
42 * hardware, its clockdomain will first be enabled; and when a clock
43 * is disabled in the hardware, its clockdomain will be disabled
46 static bool clkdm_control
= true;
49 * OMAP2+ specific clock functions
52 /* Private functions */
55 * _omap2_module_wait_ready - wait for an OMAP module to leave IDLE
56 * @clk: struct clk * belonging to the module
58 * If the necessary clocks for the OMAP hardware IP block that
59 * corresponds to clock @clk are enabled, then wait for the module to
60 * indicate readiness (i.e., to leave IDLE). This code does not
61 * belong in the clock code and will be moved in the medium term to
62 * module-dependent code. No return value.
64 static void _omap2_module_wait_ready(struct clk
*clk
)
66 void __iomem
*companion_reg
, *idlest_reg
;
67 u8 other_bit
, idlest_bit
, idlest_val
;
69 /* Not all modules have multiple clocks that their IDLEST depends on */
70 if (clk
->ops
->find_companion
) {
71 clk
->ops
->find_companion(clk
, &companion_reg
, &other_bit
);
72 if (!(__raw_readl(companion_reg
) & (1 << other_bit
)))
76 clk
->ops
->find_idlest(clk
, &idlest_reg
, &idlest_bit
, &idlest_val
);
78 omap2_cm_wait_idlest(idlest_reg
, (1 << idlest_bit
), idlest_val
,
82 /* Public functions */
85 * omap2_init_clk_clkdm - look up a clockdomain name, store pointer in clk
86 * @clk: OMAP clock struct ptr to use
88 * Convert a clockdomain name stored in a struct clk 'clk' into a
89 * clockdomain pointer, and save it into the struct clk. Intended to be
90 * called during clk_register(). No return value.
92 void omap2_init_clk_clkdm(struct clk
*clk
)
94 struct clockdomain
*clkdm
;
99 clkdm
= clkdm_lookup(clk
->clkdm_name
);
101 pr_debug("clock: associated clk %s to clkdm %s\n",
102 clk
->name
, clk
->clkdm_name
);
105 pr_debug("clock: could not associate clk %s to "
106 "clkdm %s\n", clk
->name
, clk
->clkdm_name
);
111 * omap2_clk_disable_clkdm_control - disable clkdm control on clk enable/disable
113 * Prevent the OMAP clock code from calling into the clockdomain code
114 * when a hardware clock in that clockdomain is enabled or disabled.
115 * Intended to be called at init time from omap*_clk_init(). No
118 void __init
omap2_clk_disable_clkdm_control(void)
120 clkdm_control
= false;
124 * omap2_clk_dflt_find_companion - find companion clock to @clk
125 * @clk: struct clk * to find the companion clock of
126 * @other_reg: void __iomem ** to return the companion clock CM_*CLKEN va in
127 * @other_bit: u8 ** to return the companion clock bit shift in
129 * Note: We don't need special code here for INVERT_ENABLE for the
130 * time being since INVERT_ENABLE only applies to clocks enabled by
133 * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes it's
134 * just a matter of XORing the bits.
136 * Some clocks don't have companion clocks. For example, modules with
137 * only an interface clock (such as MAILBOXES) don't have a companion
138 * clock. Right now, this code relies on the hardware exporting a bit
139 * in the correct companion register that indicates that the
140 * nonexistent 'companion clock' is active. Future patches will
141 * associate this type of code with per-module data structures to
142 * avoid this issue, and remove the casts. No return value.
144 void omap2_clk_dflt_find_companion(struct clk
*clk
, void __iomem
**other_reg
,
150 * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes
151 * it's just a matter of XORing the bits.
153 r
= ((__force u32
)clk
->enable_reg
^ (CM_FCLKEN
^ CM_ICLKEN
));
155 *other_reg
= (__force
void __iomem
*)r
;
156 *other_bit
= clk
->enable_bit
;
160 * omap2_clk_dflt_find_idlest - find CM_IDLEST reg va, bit shift for @clk
161 * @clk: struct clk * to find IDLEST info for
162 * @idlest_reg: void __iomem ** to return the CM_IDLEST va in
163 * @idlest_bit: u8 * to return the CM_IDLEST bit shift in
164 * @idlest_val: u8 * to return the idle status indicator
166 * Return the CM_IDLEST register address and bit shift corresponding
167 * to the module that "owns" this clock. This default code assumes
168 * that the CM_IDLEST bit shift is the CM_*CLKEN bit shift, and that
169 * the IDLEST register address ID corresponds to the CM_*CLKEN
170 * register address ID (e.g., that CM_FCLKEN2 corresponds to
171 * CM_IDLEST2). This is not true for all modules. No return value.
173 void omap2_clk_dflt_find_idlest(struct clk
*clk
, void __iomem
**idlest_reg
,
174 u8
*idlest_bit
, u8
*idlest_val
)
178 r
= (((__force u32
)clk
->enable_reg
& ~0xf0) | 0x20);
179 *idlest_reg
= (__force
void __iomem
*)r
;
180 *idlest_bit
= clk
->enable_bit
;
183 * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
184 * 34xx reverses this, just to keep us on our toes
185 * AM35xx uses both, depending on the module.
187 if (cpu_is_omap24xx())
188 *idlest_val
= OMAP24XX_CM_IDLEST_VAL
;
189 else if (cpu_is_omap34xx())
190 *idlest_val
= OMAP34XX_CM_IDLEST_VAL
;
196 int omap2_dflt_clk_enable(struct clk
*clk
)
200 if (unlikely(clk
->enable_reg
== NULL
)) {
201 pr_err("clock.c: Enable for %s without enable code\n",
203 return 0; /* REVISIT: -EINVAL */
206 v
= __raw_readl(clk
->enable_reg
);
207 if (clk
->flags
& INVERT_ENABLE
)
208 v
&= ~(1 << clk
->enable_bit
);
210 v
|= (1 << clk
->enable_bit
);
211 __raw_writel(v
, clk
->enable_reg
);
212 v
= __raw_readl(clk
->enable_reg
); /* OCP barrier */
214 if (clk
->ops
->find_idlest
)
215 _omap2_module_wait_ready(clk
);
220 void omap2_dflt_clk_disable(struct clk
*clk
)
224 if (!clk
->enable_reg
) {
226 * 'Independent' here refers to a clock which is not
227 * controlled by its parent.
229 printk(KERN_ERR
"clock: clk_disable called on independent "
230 "clock %s which has no enable_reg\n", clk
->name
);
234 v
= __raw_readl(clk
->enable_reg
);
235 if (clk
->flags
& INVERT_ENABLE
)
236 v
|= (1 << clk
->enable_bit
);
238 v
&= ~(1 << clk
->enable_bit
);
239 __raw_writel(v
, clk
->enable_reg
);
240 /* No OCP barrier needed here since it is a disable operation */
243 const struct clkops clkops_omap2_dflt_wait
= {
244 .enable
= omap2_dflt_clk_enable
,
245 .disable
= omap2_dflt_clk_disable
,
246 .find_companion
= omap2_clk_dflt_find_companion
,
247 .find_idlest
= omap2_clk_dflt_find_idlest
,
250 const struct clkops clkops_omap2_dflt
= {
251 .enable
= omap2_dflt_clk_enable
,
252 .disable
= omap2_dflt_clk_disable
,
256 * omap2_clk_disable - disable a clock, if the system is not using it
257 * @clk: struct clk * to disable
259 * Decrements the usecount on struct clk @clk. If there are no users
260 * left, call the clkops-specific clock disable function to disable it
261 * in hardware. If the clock is part of a clockdomain (which they all
262 * should be), request that the clockdomain be disabled. (It too has
263 * a usecount, and so will not be disabled in the hardware until it no
264 * longer has any users.) If the clock has a parent clock (most of
265 * them do), then call ourselves, recursing on the parent clock. This
266 * can cause an entire branch of the clock tree to be powered off by
267 * simply disabling one clock. Intended to be called with the clockfw_lock
268 * spinlock held. No return value.
270 void omap2_clk_disable(struct clk
*clk
)
272 if (clk
->usecount
== 0) {
273 WARN(1, "clock: %s: omap2_clk_disable() called, but usecount "
274 "already 0?", clk
->name
);
278 pr_debug("clock: %s: decrementing usecount\n", clk
->name
);
282 if (clk
->usecount
> 0)
285 pr_debug("clock: %s: disabling in hardware\n", clk
->name
);
287 if (clk
->ops
&& clk
->ops
->disable
) {
288 trace_clock_disable(clk
->name
, 0, smp_processor_id());
289 clk
->ops
->disable(clk
);
292 if (clkdm_control
&& clk
->clkdm
)
293 clkdm_clk_disable(clk
->clkdm
, clk
);
296 omap2_clk_disable(clk
->parent
);
300 * omap2_clk_enable - request that the system enable a clock
301 * @clk: struct clk * to enable
303 * Increments the usecount on struct clk @clk. If there were no users
304 * previously, then recurse up the clock tree, enabling all of the
305 * clock's parents and all of the parent clockdomains, and finally,
306 * enabling @clk's clockdomain, and @clk itself. Intended to be
307 * called with the clockfw_lock spinlock held. Returns 0 upon success
308 * or a negative error code upon failure.
310 int omap2_clk_enable(struct clk
*clk
)
314 pr_debug("clock: %s: incrementing usecount\n", clk
->name
);
318 if (clk
->usecount
> 1)
321 pr_debug("clock: %s: enabling in hardware\n", clk
->name
);
324 ret
= omap2_clk_enable(clk
->parent
);
326 WARN(1, "clock: %s: could not enable parent %s: %d\n",
327 clk
->name
, clk
->parent
->name
, ret
);
332 if (clkdm_control
&& clk
->clkdm
) {
333 ret
= clkdm_clk_enable(clk
->clkdm
, clk
);
335 WARN(1, "clock: %s: could not enable clockdomain %s: "
336 "%d\n", clk
->name
, clk
->clkdm
->name
, ret
);
341 if (clk
->ops
&& clk
->ops
->enable
) {
342 trace_clock_enable(clk
->name
, 1, smp_processor_id());
343 ret
= clk
->ops
->enable(clk
);
345 WARN(1, "clock: %s: could not enable: %d\n",
354 if (clkdm_control
&& clk
->clkdm
)
355 clkdm_clk_disable(clk
->clkdm
, clk
);
358 omap2_clk_disable(clk
->parent
);
365 /* Given a clock and a rate apply a clock specific rounding function */
366 long omap2_clk_round_rate(struct clk
*clk
, unsigned long rate
)
369 return clk
->round_rate(clk
, rate
);
374 /* Set the clock rate for a clock source */
375 int omap2_clk_set_rate(struct clk
*clk
, unsigned long rate
)
379 pr_debug("clock: set_rate for clock %s to rate %ld\n", clk
->name
, rate
);
381 /* dpll_ck, core_ck, virt_prcm_set; plus all clksel clocks */
383 trace_clock_set_rate(clk
->name
, rate
, smp_processor_id());
384 ret
= clk
->set_rate(clk
, rate
);
390 int omap2_clk_set_parent(struct clk
*clk
, struct clk
*new_parent
)
395 if (clk
->parent
== new_parent
)
398 return omap2_clksel_set_parent(clk
, new_parent
);
401 /* OMAP3/4 non-CORE DPLL clkops */
403 #if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_ARCH_OMAP4)
405 const struct clkops clkops_omap3_noncore_dpll_ops
= {
406 .enable
= omap3_noncore_dpll_enable
,
407 .disable
= omap3_noncore_dpll_disable
,
408 .allow_idle
= omap3_dpll_allow_idle
,
409 .deny_idle
= omap3_dpll_deny_idle
,
412 const struct clkops clkops_omap3_core_dpll_ops
= {
413 .allow_idle
= omap3_dpll_allow_idle
,
414 .deny_idle
= omap3_dpll_deny_idle
,
420 * OMAP2+ clock reset and init functions
423 #ifdef CONFIG_OMAP_RESET_CLOCKS
424 void omap2_clk_disable_unused(struct clk
*clk
)
428 v
= (clk
->flags
& INVERT_ENABLE
) ? (1 << clk
->enable_bit
) : 0;
430 regval32
= __raw_readl(clk
->enable_reg
);
431 if ((regval32
& (1 << clk
->enable_bit
)) == v
)
434 pr_debug("Disabling unused clock \"%s\"\n", clk
->name
);
435 if (cpu_is_omap34xx()) {
436 omap2_clk_enable(clk
);
437 omap2_clk_disable(clk
);
439 clk
->ops
->disable(clk
);
441 if (clk
->clkdm
!= NULL
)
442 pwrdm_clkdm_state_switch(clk
->clkdm
);
447 * omap2_clk_switch_mpurate_at_boot - switch ARM MPU rate by boot-time argument
448 * @mpurate_ck_name: clk name of the clock to change rate
450 * Change the ARM MPU clock rate to the rate specified on the command
451 * line, if one was specified. @mpurate_ck_name should be
452 * "virt_prcm_set" on OMAP2xxx and "dpll1_ck" on OMAP34xx/OMAP36xx.
453 * XXX Does not handle voltage scaling - on OMAP2xxx this is currently
454 * handled by the virt_prcm_set clock, but this should be handled by
455 * the OPP layer. XXX This is intended to be handled by the OPP layer
456 * code in the near future and should be removed from the clock code.
457 * Returns -EINVAL if 'mpurate' is zero or if clk_set_rate() rejects
458 * the rate, -ENOENT if the struct clk referred to by @mpurate_ck_name
459 * cannot be found, or 0 upon success.
461 int __init
omap2_clk_switch_mpurate_at_boot(const char *mpurate_ck_name
)
463 struct clk
*mpurate_ck
;
469 mpurate_ck
= clk_get(NULL
, mpurate_ck_name
);
470 if (WARN(IS_ERR(mpurate_ck
), "Failed to get %s.\n", mpurate_ck_name
))
473 r
= clk_set_rate(mpurate_ck
, mpurate
);
474 if (IS_ERR_VALUE(r
)) {
475 WARN(1, "clock: %s: unable to set MPU rate to %d: %d\n",
476 mpurate_ck
->name
, mpurate
, r
);
482 recalculate_root_clocks();
490 * omap2_clk_print_new_rates - print summary of current clock tree rates
491 * @hfclkin_ck_name: clk name for the off-chip HF oscillator
492 * @core_ck_name: clk name for the on-chip CORE_CLK
493 * @mpu_ck_name: clk name for the ARM MPU clock
495 * Prints a short message to the console with the HFCLKIN oscillator
496 * rate, the rate of the CORE clock, and the rate of the ARM MPU clock.
497 * Called by the boot-time MPU rate switching code. XXX This is intended
498 * to be handled by the OPP layer code in the near future and should be
499 * removed from the clock code. No return value.
501 void __init
omap2_clk_print_new_rates(const char *hfclkin_ck_name
,
502 const char *core_ck_name
,
503 const char *mpu_ck_name
)
505 struct clk
*hfclkin_ck
, *core_ck
, *mpu_ck
;
506 unsigned long hfclkin_rate
;
508 mpu_ck
= clk_get(NULL
, mpu_ck_name
);
509 if (WARN(IS_ERR(mpu_ck
), "clock: failed to get %s.\n", mpu_ck_name
))
512 core_ck
= clk_get(NULL
, core_ck_name
);
513 if (WARN(IS_ERR(core_ck
), "clock: failed to get %s.\n", core_ck_name
))
516 hfclkin_ck
= clk_get(NULL
, hfclkin_ck_name
);
517 if (WARN(IS_ERR(hfclkin_ck
), "Failed to get %s.\n", hfclkin_ck_name
))
520 hfclkin_rate
= clk_get_rate(hfclkin_ck
);
522 pr_info("Switched to new clocking rate (Crystal/Core/MPU): "
523 "%ld.%01ld/%ld/%ld MHz\n",
524 (hfclkin_rate
/ 1000000),
525 ((hfclkin_rate
/ 100000) % 10),
526 (clk_get_rate(core_ck
) / 1000000),
527 (clk_get_rate(mpu_ck
) / 1000000));
532 struct clk_functions omap2_clk_functions
= {
533 .clk_enable
= omap2_clk_enable
,
534 .clk_disable
= omap2_clk_disable
,
535 .clk_round_rate
= omap2_clk_round_rate
,
536 .clk_set_rate
= omap2_clk_set_rate
,
537 .clk_set_parent
= omap2_clk_set_parent
,
538 .clk_disable_unused
= omap2_clk_disable_unused
,
539 #ifdef CONFIG_CPU_FREQ
540 /* These will be removed when the OPP code is integrated */
541 .clk_init_cpufreq_table
= omap2_clk_init_cpufreq_table
,
542 .clk_exit_cpufreq_table
= omap2_clk_exit_cpufreq_table
,