1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/*
* DPLL + CORE_CLK composite clock functions
*
* Copyright (C) 2005-2008 Texas Instruments, Inc.
* Copyright (C) 2004-2010 Nokia Corporation
*
* Contacts:
* Richard Woodruff <r-woodruff2@ti.com>
* Paul Walmsley
*
* Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
* Gordon McNutt and RidgeRun, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* XXX The DPLL and CORE clocks should be split into two separate clock
* types.
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/clk.h>
#include <linux/io.h>
#include "clock.h"
#include "clock2xxx.h"
#include "opp2xxx.h"
#include "cm2xxx.h"
#include "cm-regbits-24xx.h"
#include "sdrc.h"
#include "sram.h"
/* #define DOWN_VARIABLE_DPLL 1 */ /* Experimental */
/*
* dpll_core_ck: pointer to the combined dpll_ck + core_ck on OMAP2xxx
* (currently defined as "dpll_ck" in the OMAP2xxx clock tree). Set
* during dpll_ck init and used later by omap2xxx_clk_get_core_rate().
*/
static struct clk_hw_omap *dpll_core_ck;
/**
* omap2xxx_clk_get_core_rate - return the CORE_CLK rate
*
* Returns the CORE_CLK rate. CORE_CLK can have one of three rate
* sources on OMAP2xxx: the DPLL CLKOUT rate, DPLL CLKOUTX2, or 32KHz
* (the latter is unusual). This currently should be called with
* struct clk *dpll_ck, which is a composite clock of dpll_ck and
* core_ck.
*/
unsigned long omap2xxx_clk_get_core_rate(void)
{
long long core_clk;
u32 v;
WARN_ON(!dpll_core_ck);
core_clk = omap2_get_dpll_rate(dpll_core_ck);
v = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
v &= OMAP24XX_CORE_CLK_SRC_MASK;
if (v == CORE_CLK_SRC_32K)
core_clk = 32768;
else
core_clk *= v;
return core_clk;
}
/*
* Uses the current prcm set to tell if a rate is valid.
* You can go slower, but not faster within a given rate set.
*/
static long omap2_dpllcore_round_rate(unsigned long target_rate)
{
u32 high, low, core_clk_src;
core_clk_src = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
core_clk_src &= OMAP24XX_CORE_CLK_SRC_MASK;
if (core_clk_src == CORE_CLK_SRC_DPLL) { /* DPLL clockout */
high = curr_prcm_set->dpll_speed * 2;
low = curr_prcm_set->dpll_speed;
} else { /* DPLL clockout x 2 */
high = curr_prcm_set->dpll_speed;
low = curr_prcm_set->dpll_speed / 2;
}
#ifdef DOWN_VARIABLE_DPLL
if (target_rate > high)
return high;
else
return target_rate;
#else
if (target_rate > low)
return high;
else
return low;
#endif
}
unsigned long omap2_dpllcore_recalc(struct clk_hw *hw,
unsigned long parent_rate)
{
return omap2xxx_clk_get_core_rate();
}
int omap2_reprogram_dpllcore(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
u32 cur_rate, low, mult, div, valid_rate, done_rate;
u32 bypass = 0;
struct prcm_config tmpset;
const struct dpll_data *dd;
cur_rate = omap2xxx_clk_get_core_rate();
mult = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
mult &= OMAP24XX_CORE_CLK_SRC_MASK;
if ((rate == (cur_rate / 2)) && (mult == 2)) {
omap2xxx_sdrc_reprogram(CORE_CLK_SRC_DPLL, 1);
} else if ((rate == (cur_rate * 2)) && (mult == 1)) {
omap2xxx_sdrc_reprogram(CORE_CLK_SRC_DPLL_X2, 1);
} else if (rate != cur_rate) {
valid_rate = omap2_dpllcore_round_rate(rate);
if (valid_rate != rate)
return -EINVAL;
if (mult == 1)
low = curr_prcm_set->dpll_speed;
else
low = curr_prcm_set->dpll_speed / 2;
dd = clk->dpll_data;
if (!dd)
return -EINVAL;
tmpset.cm_clksel1_pll = __raw_readl(dd->mult_div1_reg);
tmpset.cm_clksel1_pll &= ~(dd->mult_mask |
dd->div1_mask);
div = ((curr_prcm_set->xtal_speed / 1000000) - 1);
tmpset.cm_clksel2_pll = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
tmpset.cm_clksel2_pll &= ~OMAP24XX_CORE_CLK_SRC_MASK;
if (rate > low) {
tmpset.cm_clksel2_pll |= CORE_CLK_SRC_DPLL_X2;
mult = ((rate / 2) / 1000000);
done_rate = CORE_CLK_SRC_DPLL_X2;
} else {
tmpset.cm_clksel2_pll |= CORE_CLK_SRC_DPLL;
mult = (rate / 1000000);
done_rate = CORE_CLK_SRC_DPLL;
}
tmpset.cm_clksel1_pll |= (div << __ffs(dd->mult_mask));
tmpset.cm_clksel1_pll |= (mult << __ffs(dd->div1_mask));
/* Worst case */
tmpset.base_sdrc_rfr = SDRC_RFR_CTRL_BYPASS;
if (rate == curr_prcm_set->xtal_speed) /* If asking for 1-1 */
bypass = 1;
/* For omap2xxx_sdrc_init_params() */
omap2xxx_sdrc_reprogram(CORE_CLK_SRC_DPLL_X2, 1);
/* Force dll lock mode */
omap2_set_prcm(tmpset.cm_clksel1_pll, tmpset.base_sdrc_rfr,
bypass);
/* Errata: ret dll entry state */
omap2xxx_sdrc_init_params(omap2xxx_sdrc_dll_is_unlocked());
omap2xxx_sdrc_reprogram(done_rate, 0);
}
return 0;
}
/**
* omap2xxx_clkt_dpllcore_init - clk init function for dpll_ck
* @clk: struct clk *dpll_ck
*
* Store a local copy of @clk in dpll_core_ck so other code can query
* the core rate without having to clk_get(), which can sleep. Must
* only be called once. No return value. XXX If the clock
* registration process is ever changed such that dpll_ck is no longer
* statically defined, this code may need to change to increment some
* kind of use count on dpll_ck.
*/
void omap2xxx_clkt_dpllcore_init(struct clk_hw *hw)
{
WARN(dpll_core_ck, "dpll_core_ck already set - should never happen");
dpll_core_ck = to_clk_hw_omap(hw);
}
|
