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
|
/*
* OMAP34xx M2 divider clock code
*
* Copyright (C) 2007-2008 Texas Instruments, Inc.
* Copyright (C) 2007-2010 Nokia Corporation
*
* Paul Walmsley
* Jouni Högander
*
* Parts of this code are based on code written by
* Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
*
* 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.
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/clk.h>
#include <linux/io.h>
#include "clock.h"
#include "clock3xxx.h"
#include "sdrc.h"
#include "sram.h"
#define CYCLES_PER_MHZ 1000000
struct clk *sdrc_ick_p, *arm_fck_p;
/*
* CORE DPLL (DPLL3) M2 divider rate programming functions
*
* These call into SRAM code to do the actual CM writes, since the SDRAM
* is clocked from DPLL3.
*/
/**
* omap3_core_dpll_m2_set_rate - set CORE DPLL M2 divider
* @clk: struct clk * of DPLL to set
* @rate: rounded target rate
*
* Program the DPLL M2 divider with the rounded target rate. Returns
* -EINVAL upon error, or 0 upon success.
*/
int omap3_core_dpll_m2_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
u32 new_div = 0;
u32 unlock_dll = 0;
u32 c;
unsigned long validrate, sdrcrate, _mpurate;
struct omap_sdrc_params *sdrc_cs0;
struct omap_sdrc_params *sdrc_cs1;
int ret;
unsigned long clkrate;
if (!clk || !rate)
return -EINVAL;
new_div = DIV_ROUND_UP(parent_rate, rate);
validrate = parent_rate / new_div;
if (validrate != rate)
return -EINVAL;
sdrcrate = clk_get_rate(sdrc_ick_p);
clkrate = clk_hw_get_rate(hw);
if (rate > clkrate)
sdrcrate <<= ((rate / clkrate) >> 1);
else
sdrcrate >>= ((clkrate / rate) >> 1);
ret = omap2_sdrc_get_params(sdrcrate, &sdrc_cs0, &sdrc_cs1);
if (ret)
return -EINVAL;
if (sdrcrate < MIN_SDRC_DLL_LOCK_FREQ) {
pr_debug("clock: will unlock SDRC DLL\n");
unlock_dll = 1;
}
/*
* XXX This only needs to be done when the CPU frequency changes
*/
_mpurate = clk_get_rate(arm_fck_p) / CYCLES_PER_MHZ;
c = (_mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT;
c += 1; /* for safety */
c *= SDRC_MPURATE_LOOPS;
c >>= SDRC_MPURATE_SCALE;
if (c == 0)
c = 1;
pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n",
clkrate, validrate);
pr_debug("clock: SDRC CS0 timing params used: RFR %08x CTRLA %08x CTRLB %08x MR %08x\n",
sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
sdrc_cs0->actim_ctrlb, sdrc_cs0->mr);
if (sdrc_cs1)
pr_debug("clock: SDRC CS1 timing params used: RFR %08x CTRLA %08x CTRLB %08x MR %08x\n",
sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla,
sdrc_cs1->actim_ctrlb, sdrc_cs1->mr);
if (sdrc_cs1)
omap3_configure_core_dpll(
new_div, unlock_dll, c, rate > clkrate,
sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
sdrc_cs0->actim_ctrlb, sdrc_cs0->mr,
sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla,
sdrc_cs1->actim_ctrlb, sdrc_cs1->mr);
else
omap3_configure_core_dpll(
new_div, unlock_dll, c, rate > clkrate,
sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla,
sdrc_cs0->actim_ctrlb, sdrc_cs0->mr,
0, 0, 0, 0);
return 0;
}
|
