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authorBen Dooks <ben-linux@fluff.org>2008-10-21 09:06:59 -0400
committerBen Dooks <ben-linux@fluff.org>2008-12-15 16:53:38 -0500
commit952b564b4d26964e3114d02368741e192e30ae28 (patch)
tree084dcb7af82e0b8a1e8c0ba38eef8249d4f6acc2 /arch/arm/plat-s3c64xx
parentaa64ea3f78496bcd7d72d5caffa3d0bf43e84e54 (diff)
[ARM] S3C64XX: Add PLL definitions
Add definitions for the s3c6400 epll and main pll as well as functions to decode the rate. Add Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-s3c64xx')
-rw-r--r--arch/arm/plat-s3c64xx/include/plat/pll.h74
1 files changed, 74 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c64xx/include/plat/pll.h b/arch/arm/plat-s3c64xx/include/plat/pll.h
new file mode 100644
index 000000000000..1a8576422f17
--- /dev/null
+++ b/arch/arm/plat-s3c64xx/include/plat/pll.h
@@ -0,0 +1,74 @@
1/* arch/arm/plat-s3c64xx/include/plat/pll.h
2 *
3 * Copyright 2008 Openmoko, Inc.
4 * Copyright 2008 Simtec Electronics
5 * Ben Dooks <ben@simtec.co.uk>
6 * http://armlinux.simtec.co.uk/
7 *
8 * S3C64XX PLL code
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13*/
14
15#define S3C6400_PLL_MDIV_MASK ((1 << (25-16)) - 1)
16#define S3C6400_PLL_PDIV_MASK ((1 << (13-8)) - 1)
17#define S3C6400_PLL_SDIV_MASK ((1 << (2-0)) - 1)
18#define S3C6400_PLL_MDIV_SHIFT (16)
19#define S3C6400_PLL_PDIV_SHIFT (8)
20#define S3C6400_PLL_SDIV_SHIFT (0)
21
22#include <asm/div64.h>
23
24static inline unsigned long s3c6400_get_pll(unsigned long baseclk,
25 u32 pllcon)
26{
27 u32 mdiv, pdiv, sdiv;
28 u64 fvco = baseclk;
29
30 mdiv = (pllcon >> S3C6400_PLL_MDIV_SHIFT) & S3C6400_PLL_MDIV_MASK;
31 pdiv = (pllcon >> S3C6400_PLL_PDIV_SHIFT) & S3C6400_PLL_PDIV_MASK;
32 sdiv = (pllcon >> S3C6400_PLL_SDIV_SHIFT) & S3C6400_PLL_SDIV_MASK;
33
34 fvco *= mdiv;
35 do_div(fvco, (pdiv << sdiv));
36
37 return (unsigned long)fvco;
38}
39
40#define S3C6400_EPLL_MDIV_MASK ((1 << (23-16)) - 1)
41#define S3C6400_EPLL_PDIV_MASK ((1 << (13-8)) - 1)
42#define S3C6400_EPLL_SDIV_MASK ((1 << (2-0)) - 1)
43#define S3C6400_EPLL_MDIV_SHIFT (16)
44#define S3C6400_EPLL_PDIV_SHIFT (8)
45#define S3C6400_EPLL_SDIV_SHIFT (0)
46#define S3C6400_EPLL_KDIV_MASK (0xffff)
47
48static inline unsigned long s3c6400_get_epll(unsigned long baseclk)
49{
50 unsigned long result;
51 u32 epll0 = __raw_readl(S3C_EPLL_CON0);
52 u32 epll1 = __raw_readl(S3C_EPLL_CON1);
53 u32 mdiv, pdiv, sdiv, kdiv;
54 u64 tmp;
55
56 mdiv = (epll0 >> S3C6400_EPLL_MDIV_SHIFT) & S3C6400_EPLL_MDIV_MASK;
57 pdiv = (epll0 >> S3C6400_EPLL_PDIV_SHIFT) & S3C6400_EPLL_PDIV_MASK;
58 sdiv = (epll0 >> S3C6400_EPLL_SDIV_SHIFT) & S3C6400_EPLL_SDIV_MASK;
59 kdiv = epll1 & S3C6400_EPLL_KDIV_MASK;
60
61 /* We need to multiple baseclk by mdiv (the integer part) and kdiv
62 * which is in 2^16ths, so shift mdiv up (does not overflow) and
63 * add kdiv before multiplying. The use of tmp is to avoid any
64 * overflows before shifting bac down into result when multipling
65 * by the mdiv and kdiv pair.
66 */
67
68 tmp = baseclk;
69 tmp *= (mdiv << 16) + kdiv;
70 do_div(tmp, (pdiv << sdiv));
71 result = tmp >> 16;
72
73 return result;
74}