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35e424e2 PW |
1 | /* |
2 | * OMAP34xx M2 divider clock code | |
3 | * | |
4 | * Copyright (C) 2007-2008 Texas Instruments, Inc. | |
5 | * Copyright (C) 2007-2010 Nokia Corporation | |
6 | * | |
7 | * Paul Walmsley | |
8 | * Jouni Högander | |
9 | * | |
10 | * Parts of this code are based on code written by | |
11 | * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu | |
12 | * | |
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. | |
16 | */ | |
17 | #undef DEBUG | |
18 | ||
19 | #include <linux/kernel.h> | |
20 | #include <linux/errno.h> | |
21 | #include <linux/clk.h> | |
22 | #include <linux/io.h> | |
23 | ||
35e424e2 | 24 | #include "clock.h" |
657ebfad | 25 | #include "clock3xxx.h" |
35e424e2 PW |
26 | #include "clock34xx.h" |
27 | #include "sdrc.h" | |
bf027ca1 | 28 | #include "sram.h" |
35e424e2 PW |
29 | |
30 | #define CYCLES_PER_MHZ 1000000 | |
31 | ||
32 | /* | |
33 | * CORE DPLL (DPLL3) M2 divider rate programming functions | |
34 | * | |
35 | * These call into SRAM code to do the actual CM writes, since the SDRAM | |
36 | * is clocked from DPLL3. | |
37 | */ | |
38 | ||
39 | /** | |
40 | * omap3_core_dpll_m2_set_rate - set CORE DPLL M2 divider | |
41 | * @clk: struct clk * of DPLL to set | |
42 | * @rate: rounded target rate | |
43 | * | |
44 | * Program the DPLL M2 divider with the rounded target rate. Returns | |
45 | * -EINVAL upon error, or 0 upon success. | |
46 | */ | |
b4777a21 RN |
47 | int omap3_core_dpll_m2_set_rate(struct clk_hw *hw, unsigned long rate, |
48 | unsigned long parent_rate) | |
35e424e2 | 49 | { |
b4777a21 | 50 | struct clk_hw_omap *clk = to_clk_hw_omap(hw); |
35e424e2 PW |
51 | u32 new_div = 0; |
52 | u32 unlock_dll = 0; | |
53 | u32 c; | |
54 | unsigned long validrate, sdrcrate, _mpurate; | |
55 | struct omap_sdrc_params *sdrc_cs0; | |
56 | struct omap_sdrc_params *sdrc_cs1; | |
57 | int ret; | |
5dcc3b97 | 58 | unsigned long clkrate; |
35e424e2 PW |
59 | |
60 | if (!clk || !rate) | |
61 | return -EINVAL; | |
62 | ||
63 | validrate = omap2_clksel_round_rate_div(clk, rate, &new_div); | |
64 | if (validrate != rate) | |
65 | return -EINVAL; | |
66 | ||
5dcc3b97 | 67 | sdrcrate = __clk_get_rate(sdrc_ick_p); |
b4777a21 | 68 | clkrate = __clk_get_rate(hw->clk); |
5dcc3b97 RN |
69 | if (rate > clkrate) |
70 | sdrcrate <<= ((rate / clkrate) >> 1); | |
35e424e2 | 71 | else |
5dcc3b97 | 72 | sdrcrate >>= ((clkrate / rate) >> 1); |
35e424e2 PW |
73 | |
74 | ret = omap2_sdrc_get_params(sdrcrate, &sdrc_cs0, &sdrc_cs1); | |
75 | if (ret) | |
76 | return -EINVAL; | |
77 | ||
78 | if (sdrcrate < MIN_SDRC_DLL_LOCK_FREQ) { | |
79 | pr_debug("clock: will unlock SDRC DLL\n"); | |
80 | unlock_dll = 1; | |
81 | } | |
82 | ||
83 | /* | |
84 | * XXX This only needs to be done when the CPU frequency changes | |
85 | */ | |
5dcc3b97 | 86 | _mpurate = __clk_get_rate(arm_fck_p) / CYCLES_PER_MHZ; |
35e424e2 PW |
87 | c = (_mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT; |
88 | c += 1; /* for safety */ | |
89 | c *= SDRC_MPURATE_LOOPS; | |
90 | c >>= SDRC_MPURATE_SCALE; | |
91 | if (c == 0) | |
92 | c = 1; | |
93 | ||
5dcc3b97 RN |
94 | pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n", |
95 | clkrate, validrate); | |
7852ec05 | 96 | pr_debug("clock: SDRC CS0 timing params used: RFR %08x CTRLA %08x CTRLB %08x MR %08x\n", |
35e424e2 PW |
97 | sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla, |
98 | sdrc_cs0->actim_ctrlb, sdrc_cs0->mr); | |
99 | if (sdrc_cs1) | |
7852ec05 PW |
100 | pr_debug("clock: SDRC CS1 timing params used: RFR %08x CTRLA %08x CTRLB %08x MR %08x\n", |
101 | sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla, | |
102 | sdrc_cs1->actim_ctrlb, sdrc_cs1->mr); | |
35e424e2 PW |
103 | |
104 | if (sdrc_cs1) | |
105 | omap3_configure_core_dpll( | |
5dcc3b97 | 106 | new_div, unlock_dll, c, rate > clkrate, |
35e424e2 PW |
107 | sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla, |
108 | sdrc_cs0->actim_ctrlb, sdrc_cs0->mr, | |
109 | sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla, | |
110 | sdrc_cs1->actim_ctrlb, sdrc_cs1->mr); | |
111 | else | |
112 | omap3_configure_core_dpll( | |
5dcc3b97 | 113 | new_div, unlock_dll, c, rate > clkrate, |
35e424e2 PW |
114 | sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla, |
115 | sdrc_cs0->actim_ctrlb, sdrc_cs0->mr, | |
116 | 0, 0, 0, 0); | |
35e424e2 PW |
117 | return 0; |
118 | } | |
119 |