2 * clocks.c - figure out sclk/cclk/vco and such
4 * Copyright (c) 2005-2008 Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
10 #include <asm/clock.h>
12 /* Get the voltage input multiplier */
15 static u_long cached_vco_pll_ctl, cached_vco;
19 pll_ctl = bfin_read_PLL_CTL();
20 if (pll_ctl == cached_vco_pll_ctl)
23 cached_vco_pll_ctl = pll_ctl;
25 msel = (pll_ctl & MSEL) >> MSEL_P;
27 msel = (MSEL >> MSEL_P) + 1;
29 cached_vco = CONFIG_CLKIN_HZ;
30 cached_vco >>= (pll_ctl & DF);
35 /* Get the Core clock */
38 static u_long cached_cclk_pll_div, cached_cclk;
44 if (pll_is_bypassed())
45 return CONFIG_CLKIN_HZ;
47 div = bfin_read_PLL_DIV();
48 if (div == cached_cclk_pll_div)
51 cached_cclk_pll_div = div;
53 csel = (div & CSEL) >> CSEL_P;
55 ssel = (div & SSEL) >> SSEL_P;
56 if (ssel && ssel < (1 << csel)) /* SCLK > CCLK */
57 cached_cclk = get_vco() / ssel;
59 cached_cclk = get_vco() >> csel;
61 cached_cclk = get_vco() / csel;
66 /* Get the System clock */
69 static u_long cached_sclk_pll_div, cached_sclk;
70 static u_long cached_sclk0, cached_sclk1, cached_dclk;
71 static u_long _get_sclk(u_long *cache)
75 if (pll_is_bypassed())
76 return CONFIG_CLKIN_HZ;
78 div = bfin_read_PLL_DIV();
79 if (div == cached_sclk_pll_div)
82 cached_sclk_pll_div = div;
84 ssel = (div & SYSSEL) >> SYSSEL_P;
85 cached_sclk = get_vco() / ssel;
87 ssel = (div & S0SEL) >> S0SEL_P;
88 cached_sclk0 = cached_sclk / ssel;
90 ssel = (div & S1SEL) >> S1SEL_P;
91 cached_sclk1 = cached_sclk / ssel;
93 ssel = (div & DSEL) >> DSEL_P;
94 cached_dclk = get_vco() / ssel;
101 return _get_sclk(&cached_sclk);
104 u_long get_sclk0(void)
106 return _get_sclk(&cached_sclk0);
109 u_long get_sclk1(void)
111 return _get_sclk(&cached_sclk1);
114 u_long get_dclk(void)
116 return _get_sclk(&cached_dclk);
120 u_long get_sclk(void)
122 static u_long cached_sclk_pll_div, cached_sclk;
125 if (pll_is_bypassed())
126 return CONFIG_CLKIN_HZ;
128 div = bfin_read_PLL_DIV();
129 if (div == cached_sclk_pll_div)
132 cached_sclk_pll_div = div;
134 ssel = (div & SSEL) >> SSEL_P;
135 cached_sclk = get_vco() / ssel;