xref: /openbmc/linux/arch/arm/mach-omap2/clock.c (revision 9cfc5c90)
1 /*
2  *  linux/arch/arm/mach-omap2/clock.c
3  *
4  *  Copyright (C) 2005-2008 Texas Instruments, Inc.
5  *  Copyright (C) 2004-2010 Nokia Corporation
6  *
7  *  Contacts:
8  *  Richard Woodruff <r-woodruff2@ti.com>
9  *  Paul Walmsley
10  *
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.
14  */
15 #undef DEBUG
16 
17 #include <linux/kernel.h>
18 #include <linux/export.h>
19 #include <linux/list.h>
20 #include <linux/errno.h>
21 #include <linux/err.h>
22 #include <linux/delay.h>
23 #include <linux/clk.h>
24 #include <linux/clk-provider.h>
25 #include <linux/io.h>
26 #include <linux/bitops.h>
27 #include <linux/of_address.h>
28 #include <asm/cpu.h>
29 
30 #include <trace/events/power.h>
31 
32 #include "soc.h"
33 #include "clockdomain.h"
34 #include "clock.h"
35 #include "cm.h"
36 #include "cm2xxx.h"
37 #include "cm3xxx.h"
38 #include "cm-regbits-24xx.h"
39 #include "cm-regbits-34xx.h"
40 #include "common.h"
41 
42 u16 cpu_mask;
43 
44 /* DPLL valid Fint frequency band limits - from 34xx TRM Section 4.7.6.2 */
45 #define OMAP3430_DPLL_FINT_BAND1_MIN	750000
46 #define OMAP3430_DPLL_FINT_BAND1_MAX	2100000
47 #define OMAP3430_DPLL_FINT_BAND2_MIN	7500000
48 #define OMAP3430_DPLL_FINT_BAND2_MAX	21000000
49 
50 /*
51  * DPLL valid Fint frequency range for OMAP36xx and OMAP4xxx.
52  * From device data manual section 4.3 "DPLL and DLL Specifications".
53  */
54 #define OMAP3PLUS_DPLL_FINT_MIN		32000
55 #define OMAP3PLUS_DPLL_FINT_MAX		52000000
56 
57 static struct ti_clk_ll_ops omap_clk_ll_ops = {
58 	.clkdm_clk_enable = clkdm_clk_enable,
59 	.clkdm_clk_disable = clkdm_clk_disable,
60 	.cm_wait_module_ready = omap_cm_wait_module_ready,
61 	.cm_split_idlest_reg = cm_split_idlest_reg,
62 };
63 
64 /**
65  * omap2_clk_setup_ll_ops - setup clock driver low-level ops
66  *
67  * Sets up clock driver low-level platform ops. These are needed
68  * for register accesses and various other misc platform operations.
69  * Returns 0 on success, -EBUSY if low level ops have been registered
70  * already.
71  */
72 int __init omap2_clk_setup_ll_ops(void)
73 {
74 	return ti_clk_setup_ll_ops(&omap_clk_ll_ops);
75 }
76 
77 /*
78  * OMAP2+ specific clock functions
79  */
80 
81 /* Private functions */
82 
83 /* Public functions */
84 
85 /**
86  * omap2_init_clk_clkdm - look up a clockdomain name, store pointer in clk
87  * @clk: OMAP clock struct ptr to use
88  *
89  * Convert a clockdomain name stored in a struct clk 'clk' into a
90  * clockdomain pointer, and save it into the struct clk.  Intended to be
91  * called during clk_register().  No return value.
92  */
93 void omap2_init_clk_clkdm(struct clk_hw *hw)
94 {
95 	struct clk_hw_omap *clk = to_clk_hw_omap(hw);
96 	struct clockdomain *clkdm;
97 	const char *clk_name;
98 
99 	if (!clk->clkdm_name)
100 		return;
101 
102 	clk_name = __clk_get_name(hw->clk);
103 
104 	clkdm = clkdm_lookup(clk->clkdm_name);
105 	if (clkdm) {
106 		pr_debug("clock: associated clk %s to clkdm %s\n",
107 			 clk_name, clk->clkdm_name);
108 		clk->clkdm = clkdm;
109 	} else {
110 		pr_debug("clock: could not associate clk %s to clkdm %s\n",
111 			 clk_name, clk->clkdm_name);
112 	}
113 }
114 
115 static int __initdata mpurate;
116 
117 /*
118  * By default we use the rate set by the bootloader.
119  * You can override this with mpurate= cmdline option.
120  */
121 static int __init omap_clk_setup(char *str)
122 {
123 	get_option(&str, &mpurate);
124 
125 	if (!mpurate)
126 		return 1;
127 
128 	if (mpurate < 1000)
129 		mpurate *= 1000000;
130 
131 	return 1;
132 }
133 __setup("mpurate=", omap_clk_setup);
134 
135 /**
136  * omap2_clk_print_new_rates - print summary of current clock tree rates
137  * @hfclkin_ck_name: clk name for the off-chip HF oscillator
138  * @core_ck_name: clk name for the on-chip CORE_CLK
139  * @mpu_ck_name: clk name for the ARM MPU clock
140  *
141  * Prints a short message to the console with the HFCLKIN oscillator
142  * rate, the rate of the CORE clock, and the rate of the ARM MPU clock.
143  * Called by the boot-time MPU rate switching code.   XXX This is intended
144  * to be handled by the OPP layer code in the near future and should be
145  * removed from the clock code.  No return value.
146  */
147 void __init omap2_clk_print_new_rates(const char *hfclkin_ck_name,
148 				      const char *core_ck_name,
149 				      const char *mpu_ck_name)
150 {
151 	struct clk *hfclkin_ck, *core_ck, *mpu_ck;
152 	unsigned long hfclkin_rate;
153 
154 	mpu_ck = clk_get(NULL, mpu_ck_name);
155 	if (WARN(IS_ERR(mpu_ck), "clock: failed to get %s.\n", mpu_ck_name))
156 		return;
157 
158 	core_ck = clk_get(NULL, core_ck_name);
159 	if (WARN(IS_ERR(core_ck), "clock: failed to get %s.\n", core_ck_name))
160 		return;
161 
162 	hfclkin_ck = clk_get(NULL, hfclkin_ck_name);
163 	if (WARN(IS_ERR(hfclkin_ck), "Failed to get %s.\n", hfclkin_ck_name))
164 		return;
165 
166 	hfclkin_rate = clk_get_rate(hfclkin_ck);
167 
168 	pr_info("Switched to new clocking rate (Crystal/Core/MPU): %ld.%01ld/%ld/%ld MHz\n",
169 		(hfclkin_rate / 1000000), ((hfclkin_rate / 100000) % 10),
170 		(clk_get_rate(core_ck) / 1000000),
171 		(clk_get_rate(mpu_ck) / 1000000));
172 }
173 
174 /**
175  * ti_clk_init_features - init clock features struct for the SoC
176  *
177  * Initializes the clock features struct based on the SoC type.
178  */
179 void __init ti_clk_init_features(void)
180 {
181 	struct ti_clk_features features = { 0 };
182 	/* Fint setup for DPLLs */
183 	if (cpu_is_omap3430()) {
184 		features.fint_min = OMAP3430_DPLL_FINT_BAND1_MIN;
185 		features.fint_max = OMAP3430_DPLL_FINT_BAND2_MAX;
186 		features.fint_band1_max = OMAP3430_DPLL_FINT_BAND1_MAX;
187 		features.fint_band2_min = OMAP3430_DPLL_FINT_BAND2_MIN;
188 	} else {
189 		features.fint_min = OMAP3PLUS_DPLL_FINT_MIN;
190 		features.fint_max = OMAP3PLUS_DPLL_FINT_MAX;
191 	}
192 
193 	/* Bypass value setup for DPLLs */
194 	if (cpu_is_omap24xx()) {
195 		features.dpll_bypass_vals |=
196 			(1 << OMAP2XXX_EN_DPLL_LPBYPASS) |
197 			(1 << OMAP2XXX_EN_DPLL_FRBYPASS);
198 	} else if (cpu_is_omap34xx()) {
199 		features.dpll_bypass_vals |=
200 			(1 << OMAP3XXX_EN_DPLL_LPBYPASS) |
201 			(1 << OMAP3XXX_EN_DPLL_FRBYPASS);
202 	} else if (soc_is_am33xx() || cpu_is_omap44xx() || soc_is_am43xx() ||
203 		   soc_is_omap54xx() || soc_is_dra7xx()) {
204 		features.dpll_bypass_vals |=
205 			(1 << OMAP4XXX_EN_DPLL_LPBYPASS) |
206 			(1 << OMAP4XXX_EN_DPLL_FRBYPASS) |
207 			(1 << OMAP4XXX_EN_DPLL_MNBYPASS);
208 	}
209 
210 	/* Jitter correction only available on OMAP343X */
211 	if (cpu_is_omap343x())
212 		features.flags |= TI_CLK_DPLL_HAS_FREQSEL;
213 
214 	/* Idlest value for interface clocks.
215 	 * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
216 	 * 34xx reverses this, just to keep us on our toes
217 	 * AM35xx uses both, depending on the module.
218 	 */
219 	if (cpu_is_omap24xx())
220 		features.cm_idlest_val = OMAP24XX_CM_IDLEST_VAL;
221 	else if (cpu_is_omap34xx())
222 		features.cm_idlest_val = OMAP34XX_CM_IDLEST_VAL;
223 
224 	/* On OMAP3430 ES1.0, DPLL4 can't be re-programmed */
225 	if (omap_rev() == OMAP3430_REV_ES1_0)
226 		features.flags |= TI_CLK_DPLL4_DENY_REPROGRAM;
227 
228 	ti_clk_setup_features(&features);
229 }
230