diff options
Diffstat (limited to 'arch/arm/mach-omap2/clkt34xx_dpll3m2.c')
-rw-r--r-- | arch/arm/mach-omap2/clkt34xx_dpll3m2.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clkt34xx_dpll3m2.c b/arch/arm/mach-omap2/clkt34xx_dpll3m2.c new file mode 100644 index 000000000000..b2b1e37bb6bb --- /dev/null +++ b/arch/arm/mach-omap2/clkt34xx_dpll3m2.c | |||
@@ -0,0 +1,121 @@ | |||
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 | |||
24 | #include <plat/clock.h> | ||
25 | #include <plat/sram.h> | ||
26 | #include <plat/sdrc.h> | ||
27 | |||
28 | #include "clock.h" | ||
29 | #include "clock3xxx.h" | ||
30 | #include "clock34xx.h" | ||
31 | #include "sdrc.h" | ||
32 | |||
33 | #define CYCLES_PER_MHZ 1000000 | ||
34 | |||
35 | /* | ||
36 | * CORE DPLL (DPLL3) M2 divider rate programming functions | ||
37 | * | ||
38 | * These call into SRAM code to do the actual CM writes, since the SDRAM | ||
39 | * is clocked from DPLL3. | ||
40 | */ | ||
41 | |||
42 | /** | ||
43 | * omap3_core_dpll_m2_set_rate - set CORE DPLL M2 divider | ||
44 | * @clk: struct clk * of DPLL to set | ||
45 | * @rate: rounded target rate | ||
46 | * | ||
47 | * Program the DPLL M2 divider with the rounded target rate. Returns | ||
48 | * -EINVAL upon error, or 0 upon success. | ||
49 | */ | ||
50 | int omap3_core_dpll_m2_set_rate(struct clk *clk, unsigned long rate) | ||
51 | { | ||
52 | u32 new_div = 0; | ||
53 | u32 unlock_dll = 0; | ||
54 | u32 c; | ||
55 | unsigned long validrate, sdrcrate, _mpurate; | ||
56 | struct omap_sdrc_params *sdrc_cs0; | ||
57 | struct omap_sdrc_params *sdrc_cs1; | ||
58 | int ret; | ||
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 | |||
67 | sdrcrate = sdrc_ick_p->rate; | ||
68 | if (rate > clk->rate) | ||
69 | sdrcrate <<= ((rate / clk->rate) >> 1); | ||
70 | else | ||
71 | sdrcrate >>= ((clk->rate / rate) >> 1); | ||
72 | |||
73 | ret = omap2_sdrc_get_params(sdrcrate, &sdrc_cs0, &sdrc_cs1); | ||
74 | if (ret) | ||
75 | return -EINVAL; | ||
76 | |||
77 | if (sdrcrate < MIN_SDRC_DLL_LOCK_FREQ) { | ||
78 | pr_debug("clock: will unlock SDRC DLL\n"); | ||
79 | unlock_dll = 1; | ||
80 | } | ||
81 | |||
82 | /* | ||
83 | * XXX This only needs to be done when the CPU frequency changes | ||
84 | */ | ||
85 | _mpurate = arm_fck_p->rate / CYCLES_PER_MHZ; | ||
86 | c = (_mpurate << SDRC_MPURATE_SCALE) >> SDRC_MPURATE_BASE_SHIFT; | ||
87 | c += 1; /* for safety */ | ||
88 | c *= SDRC_MPURATE_LOOPS; | ||
89 | c >>= SDRC_MPURATE_SCALE; | ||
90 | if (c == 0) | ||
91 | c = 1; | ||
92 | |||
93 | pr_debug("clock: changing CORE DPLL rate from %lu to %lu\n", clk->rate, | ||
94 | validrate); | ||
95 | pr_debug("clock: SDRC CS0 timing params used:" | ||
96 | " RFR %08x CTRLA %08x CTRLB %08x MR %08x\n", | ||
97 | sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla, | ||
98 | sdrc_cs0->actim_ctrlb, sdrc_cs0->mr); | ||
99 | if (sdrc_cs1) | ||
100 | pr_debug("clock: SDRC CS1 timing params used: " | ||
101 | " RFR %08x CTRLA %08x CTRLB %08x MR %08x\n", | ||
102 | sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla, | ||
103 | sdrc_cs1->actim_ctrlb, sdrc_cs1->mr); | ||
104 | |||
105 | if (sdrc_cs1) | ||
106 | omap3_configure_core_dpll( | ||
107 | new_div, unlock_dll, c, rate > clk->rate, | ||
108 | sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla, | ||
109 | sdrc_cs0->actim_ctrlb, sdrc_cs0->mr, | ||
110 | sdrc_cs1->rfr_ctrl, sdrc_cs1->actim_ctrla, | ||
111 | sdrc_cs1->actim_ctrlb, sdrc_cs1->mr); | ||
112 | else | ||
113 | omap3_configure_core_dpll( | ||
114 | new_div, unlock_dll, c, rate > clk->rate, | ||
115 | sdrc_cs0->rfr_ctrl, sdrc_cs0->actim_ctrla, | ||
116 | sdrc_cs0->actim_ctrlb, sdrc_cs0->mr, | ||
117 | 0, 0, 0, 0); | ||
118 | |||
119 | return 0; | ||
120 | } | ||
121 | |||