2 * OMAP3-specific clock framework functions
4 * Copyright (C) 2007-2008 Texas Instruments, Inc.
5 * Copyright (C) 2007-2008 Nokia Corporation
7 * Written by Paul Walmsley
8 * Testing and integration fixes by Jouni Högander
10 * Parts of this code are based on code written by
11 * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2 as
15 * published by the Free Software Foundation.
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/device.h>
22 #include <linux/list.h>
23 #include <linux/errno.h>
24 #include <linux/delay.h>
25 #include <linux/clk.h>
27 #include <linux/limits.h>
29 #include <asm/arch/clock.h>
30 #include <asm/arch/sram.h>
31 #include <asm/div64.h>
32 #include <asm/bitops.h>
36 #include "clock34xx.h"
38 #include "prm-regbits-34xx.h"
40 #include "cm-regbits-34xx.h"
42 /* CM_AUTOIDLE_PLL*.AUTO_* bit values */
43 #define DPLL_AUTOIDLE_DISABLE 0x0
44 #define DPLL_AUTOIDLE_LOW_POWER_STOP 0x1
46 #define MAX_DPLL_WAIT_TRIES 1000000
49 * omap3_dpll_recalc - recalculate DPLL rate
50 * @clk: DPLL struct clk
52 * Recalculate and propagate the DPLL rate.
54 static void omap3_dpll_recalc(struct clk *clk)
56 clk->rate = omap2_get_dpll_rate(clk);
61 /* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */
62 static void _omap3_dpll_write_clken(struct clk *clk, u8 clken_bits)
64 const struct dpll_data *dd;
68 cm_rmw_reg_bits(dd->enable_mask, clken_bits << __ffs(dd->enable_mask),
72 /* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */
73 static int _omap3_wait_dpll_status(struct clk *clk, u8 state)
75 const struct dpll_data *dd;
82 state <<= dd->idlest_bit;
83 idlest_mask = 1 << dd->idlest_bit;
85 while (((__raw_readl(dd->idlest_reg) & idlest_mask) != state) &&
86 i < MAX_DPLL_WAIT_TRIES) {
91 if (i == MAX_DPLL_WAIT_TRIES) {
92 printk(KERN_ERR "clock: %s failed transition to '%s'\n",
93 clk->name, (state) ? "locked" : "bypassed");
95 pr_debug("clock: %s transition to '%s' in %d loops\n",
96 clk->name, (state) ? "locked" : "bypassed", i);
104 /* From 3430 TRM ES2 4.7.6.2 */
105 static u16 _omap3_dpll_compute_freqsel(struct clk *clk, u8 n)
110 fint = clk->parent->rate / (n + 1);
112 pr_debug("clock: fint is %lu\n", fint);
114 if (fint >= 750000 && fint <= 1000000)
116 else if (fint > 1000000 && fint <= 1250000)
118 else if (fint > 1250000 && fint <= 1500000)
120 else if (fint > 1500000 && fint <= 1750000)
122 else if (fint > 1750000 && fint <= 2100000)
124 else if (fint > 7500000 && fint <= 10000000)
126 else if (fint > 10000000 && fint <= 12500000)
128 else if (fint > 12500000 && fint <= 15000000)
130 else if (fint > 15000000 && fint <= 17500000)
132 else if (fint > 17500000 && fint <= 21000000)
135 pr_debug("clock: unknown freqsel setting for %d\n", n);
140 /* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */
143 * _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness
144 * @clk: pointer to a DPLL struct clk
146 * Instructs a non-CORE DPLL to lock. Waits for the DPLL to report
147 * readiness before returning. Will save and restore the DPLL's
148 * autoidle state across the enable, per the CDP code. If the DPLL
149 * locked successfully, return 0; if the DPLL did not lock in the time
150 * allotted, or DPLL3 was passed in, return -EINVAL.
152 static int _omap3_noncore_dpll_lock(struct clk *clk)
157 if (clk == &dpll3_ck)
160 pr_debug("clock: locking DPLL %s\n", clk->name);
162 ai = omap3_dpll_autoidle_read(clk);
164 _omap3_dpll_write_clken(clk, DPLL_LOCKED);
168 * If no downstream clocks are enabled, CM_IDLEST bit
169 * may never become active, so don't wait for DPLL to lock.
172 omap3_dpll_allow_idle(clk);
174 r = _omap3_wait_dpll_status(clk, 1);
175 omap3_dpll_deny_idle(clk);
182 * omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness
183 * @clk: pointer to a DPLL struct clk
185 * Instructs a non-CORE DPLL to enter low-power bypass mode. In
186 * bypass mode, the DPLL's rate is set equal to its parent clock's
187 * rate. Waits for the DPLL to report readiness before returning.
188 * Will save and restore the DPLL's autoidle state across the enable,
189 * per the CDP code. If the DPLL entered bypass mode successfully,
190 * return 0; if the DPLL did not enter bypass in the time allotted, or
191 * DPLL3 was passed in, or the DPLL does not support low-power bypass,
194 static int _omap3_noncore_dpll_bypass(struct clk *clk)
199 if (clk == &dpll3_ck)
202 if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS)))
205 pr_debug("clock: configuring DPLL %s for low-power bypass\n",
208 ai = omap3_dpll_autoidle_read(clk);
210 _omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS);
212 r = _omap3_wait_dpll_status(clk, 0);
215 omap3_dpll_allow_idle(clk);
217 omap3_dpll_deny_idle(clk);
223 * _omap3_noncore_dpll_stop - instruct a DPLL to stop
224 * @clk: pointer to a DPLL struct clk
226 * Instructs a non-CORE DPLL to enter low-power stop. Will save and
227 * restore the DPLL's autoidle state across the stop, per the CDP
228 * code. If DPLL3 was passed in, or the DPLL does not support
229 * low-power stop, return -EINVAL; otherwise, return 0.
231 static int _omap3_noncore_dpll_stop(struct clk *clk)
235 if (clk == &dpll3_ck)
238 if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP)))
241 pr_debug("clock: stopping DPLL %s\n", clk->name);
243 ai = omap3_dpll_autoidle_read(clk);
245 _omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP);
248 omap3_dpll_allow_idle(clk);
250 omap3_dpll_deny_idle(clk);
256 * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
257 * @clk: pointer to a DPLL struct clk
259 * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
260 * The choice of modes depends on the DPLL's programmed rate: if it is
261 * the same as the DPLL's parent clock, it will enter bypass;
262 * otherwise, it will enter lock. This code will wait for the DPLL to
263 * indicate readiness before returning, unless the DPLL takes too long
264 * to enter the target state. Intended to be used as the struct clk's
265 * enable function. If DPLL3 was passed in, or the DPLL does not
266 * support low-power stop, or if the DPLL took too long to enter
267 * bypass or lock, return -EINVAL; otherwise, return 0.
269 static int omap3_noncore_dpll_enable(struct clk *clk)
273 if (clk == &dpll3_ck)
276 if (clk->parent->rate == clk_get_rate(clk))
277 r = _omap3_noncore_dpll_bypass(clk);
279 r = _omap3_noncore_dpll_lock(clk);
285 * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode
286 * @clk: pointer to a DPLL struct clk
288 * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock.
289 * The choice of modes depends on the DPLL's programmed rate: if it is
290 * the same as the DPLL's parent clock, it will enter bypass;
291 * otherwise, it will enter lock. This code will wait for the DPLL to
292 * indicate readiness before returning, unless the DPLL takes too long
293 * to enter the target state. Intended to be used as the struct clk's
294 * enable function. If DPLL3 was passed in, or the DPLL does not
295 * support low-power stop, or if the DPLL took too long to enter
296 * bypass or lock, return -EINVAL; otherwise, return 0.
298 static void omap3_noncore_dpll_disable(struct clk *clk)
300 if (clk == &dpll3_ck)
303 _omap3_noncore_dpll_stop(clk);
307 /* Non-CORE DPLL rate set code */
310 * omap3_noncore_dpll_program - set non-core DPLL M,N values directly
311 * @clk: struct clk * of DPLL to set
312 * @m: DPLL multiplier to set
313 * @n: DPLL divider to set
314 * @freqsel: FREQSEL value to set
316 * Program the DPLL with the supplied M, N values, and wait for the DPLL to
317 * lock.. Returns -EINVAL upon error, or 0 upon success.
319 static int omap3_noncore_dpll_program(struct clk *clk, u16 m, u8 n, u16 freqsel)
321 struct dpll_data *dd;
332 * According to the 12-5 CDP code from TI, "Limitation 2.5"
333 * on 3430ES1 prevents us from changing DPLL multipliers or dividers
336 if (is_sil_rev_equal_to(OMAP3430_REV_ES1_0) &&
337 !strcmp("dpll4_ck", clk->name)) {
338 printk(KERN_ERR "clock: DPLL4 cannot change rate due to "
339 "silicon 'Limitation 2.5' on 3430ES1.\n");
343 /* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */
344 _omap3_noncore_dpll_bypass(clk);
346 v = __raw_readl(dd->mult_div1_reg);
347 v &= ~(dd->mult_mask | dd->div1_mask);
349 /* Set mult (M), div1 (N), freqsel */
350 v |= m << __ffs(dd->mult_mask);
351 v |= n << __ffs(dd->div1_mask);
352 v |= freqsel << __ffs(dd->freqsel_mask);
354 __raw_writel(v, dd->mult_div1_reg);
356 /* We let the clock framework set the other output dividers later */
358 /* REVISIT: Set ramp-up delay? */
360 _omap3_noncore_dpll_lock(clk);
366 * omap3_noncore_dpll_set_rate - set non-core DPLL rate
367 * @clk: struct clk * of DPLL to set
368 * @rate: rounded target rate
370 * Program the DPLL with the rounded target rate. Returns -EINVAL upon
371 * error, or 0 upon success.
373 static int omap3_noncore_dpll_set_rate(struct clk *clk, unsigned long rate)
376 struct dpll_data *dd;
385 if (rate == omap2_get_dpll_rate(clk))
388 if (dd->last_rounded_rate != rate)
389 omap2_dpll_round_rate(clk, rate);
391 if (dd->last_rounded_rate == 0)
394 freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
398 omap3_noncore_dpll_program(clk, dd->last_rounded_m, dd->last_rounded_n,
401 omap3_dpll_recalc(clk);
406 /* DPLL autoidle read/set code */
410 * omap3_dpll_autoidle_read - read a DPLL's autoidle bits
411 * @clk: struct clk * of the DPLL to read
413 * Return the DPLL's autoidle bits, shifted down to bit 0. Returns
414 * -EINVAL if passed a null pointer or if the struct clk does not
415 * appear to refer to a DPLL.
417 static u32 omap3_dpll_autoidle_read(struct clk *clk)
419 const struct dpll_data *dd;
422 if (!clk || !clk->dpll_data)
427 v = __raw_readl(dd->autoidle_reg);
428 v &= dd->autoidle_mask;
429 v >>= __ffs(dd->autoidle_mask);
435 * omap3_dpll_allow_idle - enable DPLL autoidle bits
436 * @clk: struct clk * of the DPLL to operate on
438 * Enable DPLL automatic idle control. This automatic idle mode
439 * switching takes effect only when the DPLL is locked, at least on
440 * OMAP3430. The DPLL will enter low-power stop when its downstream
441 * clocks are gated. No return value.
443 static void omap3_dpll_allow_idle(struct clk *clk)
445 const struct dpll_data *dd;
447 if (!clk || !clk->dpll_data)
453 * REVISIT: CORE DPLL can optionally enter low-power bypass
454 * by writing 0x5 instead of 0x1. Add some mechanism to
455 * optionally enter this mode.
457 cm_rmw_reg_bits(dd->autoidle_mask,
458 DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask),
463 * omap3_dpll_deny_idle - prevent DPLL from automatically idling
464 * @clk: struct clk * of the DPLL to operate on
466 * Disable DPLL automatic idle control. No return value.
468 static void omap3_dpll_deny_idle(struct clk *clk)
470 const struct dpll_data *dd;
472 if (!clk || !clk->dpll_data)
477 cm_rmw_reg_bits(dd->autoidle_mask,
478 DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask),
482 /* Clock control for DPLL outputs */
485 * omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate
486 * @clk: DPLL output struct clk
488 * Using parent clock DPLL data, look up DPLL state. If locked, set our
489 * rate to the dpll_clk * 2; otherwise, just use dpll_clk.
491 static void omap3_clkoutx2_recalc(struct clk *clk)
493 const struct dpll_data *dd;
497 /* Walk up the parents of clk, looking for a DPLL */
499 while (pclk && !pclk->dpll_data)
502 /* clk does not have a DPLL as a parent? */
505 dd = pclk->dpll_data;
507 WARN_ON(!dd->control_reg || !dd->enable_mask);
509 v = __raw_readl(dd->control_reg) & dd->enable_mask;
510 v >>= __ffs(dd->enable_mask);
511 if (v != DPLL_LOCKED)
512 clk->rate = clk->parent->rate;
514 clk->rate = clk->parent->rate * 2;
516 if (clk->flags & RATE_PROPAGATES)
520 /* Common clock code */
523 * As it is structured now, this will prevent an OMAP2/3 multiboot
524 * kernel from compiling. This will need further attention.
526 #if defined(CONFIG_ARCH_OMAP3)
528 static struct clk_functions omap2_clk_functions = {
529 .clk_enable = omap2_clk_enable,
530 .clk_disable = omap2_clk_disable,
531 .clk_round_rate = omap2_clk_round_rate,
532 .clk_set_rate = omap2_clk_set_rate,
533 .clk_set_parent = omap2_clk_set_parent,
534 .clk_disable_unused = omap2_clk_disable_unused,
538 * Set clocks for bypass mode for reboot to work.
540 void omap2_clk_prepare_for_reboot(void)
542 /* REVISIT: Not ready for 343x */
546 if (vclk == NULL || sclk == NULL)
549 rate = clk_get_rate(sclk);
550 clk_set_rate(vclk, rate);
554 /* REVISIT: Move this init stuff out into clock.c */
557 * Switch the MPU rate if specified on cmdline.
558 * We cannot do this early until cmdline is parsed.
560 static int __init omap2_clk_arch_init(void)
565 /* REVISIT: not yet ready for 343x */
567 if (omap2_select_table_rate(&virt_prcm_set, mpurate))
568 printk(KERN_ERR "Could not find matching MPU rate\n");
571 recalculate_root_clocks();
573 printk(KERN_INFO "Switched to new clocking rate (Crystal/DPLL3/MPU): "
574 "%ld.%01ld/%ld/%ld MHz\n",
575 (osc_sys_ck.rate / 1000000), (osc_sys_ck.rate / 100000) % 10,
576 (core_ck.rate / 1000000), (dpll1_fck.rate / 1000000)) ;
580 arch_initcall(omap2_clk_arch_init);
582 int __init omap2_clk_init(void)
584 /* struct prcm_config *prcm; */
589 /* REVISIT: Ultimately this will be used for multiboot */
591 if (cpu_is_omap242x()) {
592 cpu_mask = RATE_IN_242X;
593 cpu_clkflg = CLOCK_IN_OMAP242X;
594 clkp = onchip_24xx_clks;
595 } else if (cpu_is_omap2430()) {
596 cpu_mask = RATE_IN_243X;
597 cpu_clkflg = CLOCK_IN_OMAP243X;
598 clkp = onchip_24xx_clks;
601 if (cpu_is_omap34xx()) {
602 cpu_mask = RATE_IN_343X;
603 cpu_clkflg = CLOCK_IN_OMAP343X;
604 clkp = onchip_34xx_clks;
607 * Update this if there are further clock changes between ES2
608 * and production parts
610 if (is_sil_rev_equal_to(OMAP3430_REV_ES1_0)) {
611 /* No 3430ES1-only rates exist, so no RATE_IN_3430ES1 */
612 cpu_clkflg |= CLOCK_IN_OMAP3430ES1;
614 cpu_mask |= RATE_IN_3430ES2;
615 cpu_clkflg |= CLOCK_IN_OMAP3430ES2;
619 clk_init(&omap2_clk_functions);
621 for (clkp = onchip_34xx_clks;
622 clkp < onchip_34xx_clks + ARRAY_SIZE(onchip_34xx_clks);
624 if ((*clkp)->flags & cpu_clkflg)
628 /* REVISIT: Not yet ready for OMAP3 */
630 /* Check the MPU rate set by bootloader */
631 clkrate = omap2_get_dpll_rate_24xx(&dpll_ck);
632 for (prcm = rate_table; prcm->mpu_speed; prcm++) {
633 if (!(prcm->flags & cpu_mask))
635 if (prcm->xtal_speed != sys_ck.rate)
637 if (prcm->dpll_speed <= clkrate)
640 curr_prcm_set = prcm;
643 recalculate_root_clocks();
645 printk(KERN_INFO "Clocking rate (Crystal/DPLL/ARM core): "
646 "%ld.%01ld/%ld/%ld MHz\n",
647 (osc_sys_ck.rate / 1000000), (osc_sys_ck.rate / 100000) % 10,
648 (core_ck.rate / 1000000), (arm_fck.rate / 1000000));
651 * Only enable those clocks we will need, let the drivers
652 * enable other clocks as necessary
654 clk_enable_init_clocks();
656 /* Avoid sleeping during omap2_clk_prepare_for_reboot() */
657 /* REVISIT: not yet ready for 343x */
659 vclk = clk_get(NULL, "virt_prcm_set");
660 sclk = clk_get(NULL, "sys_ck");