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| -rw-r--r-- | arch/arm/plat-s3c64xx/include/plat/pll.h | 74 |
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 00000000000..1a8576422f1 --- /dev/null +++ b/arch/arm/plat-s3c64xx/include/plat/pll.h @@ -0,0 +1,74 @@ +/* arch/arm/plat-s3c64xx/include/plat/pll.h + * + * Copyright 2008 Openmoko, Inc. + * Copyright 2008 Simtec Electronics + * Ben Dooks <ben@simtec.co.uk> + * http://armlinux.simtec.co.uk/ + * + * S3C64XX PLL code + * + * 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. +*/ + +#define S3C6400_PLL_MDIV_MASK ((1 << (25-16)) - 1) +#define S3C6400_PLL_PDIV_MASK ((1 << (13-8)) - 1) +#define S3C6400_PLL_SDIV_MASK ((1 << (2-0)) - 1) +#define S3C6400_PLL_MDIV_SHIFT (16) +#define S3C6400_PLL_PDIV_SHIFT (8) +#define S3C6400_PLL_SDIV_SHIFT (0) + +#include <asm/div64.h> + +static inline unsigned long s3c6400_get_pll(unsigned long baseclk, + u32 pllcon) +{ + u32 mdiv, pdiv, sdiv; + u64 fvco = baseclk; + + mdiv = (pllcon >> S3C6400_PLL_MDIV_SHIFT) & S3C6400_PLL_MDIV_MASK; + pdiv = (pllcon >> S3C6400_PLL_PDIV_SHIFT) & S3C6400_PLL_PDIV_MASK; + sdiv = (pllcon >> S3C6400_PLL_SDIV_SHIFT) & S3C6400_PLL_SDIV_MASK; + + fvco *= mdiv; + do_div(fvco, (pdiv << sdiv)); + + return (unsigned long)fvco; +} + +#define S3C6400_EPLL_MDIV_MASK ((1 << (23-16)) - 1) +#define S3C6400_EPLL_PDIV_MASK ((1 << (13-8)) - 1) +#define S3C6400_EPLL_SDIV_MASK ((1 << (2-0)) - 1) +#define S3C6400_EPLL_MDIV_SHIFT (16) +#define S3C6400_EPLL_PDIV_SHIFT (8) +#define S3C6400_EPLL_SDIV_SHIFT (0) +#define S3C6400_EPLL_KDIV_MASK (0xffff) + +static inline unsigned long s3c6400_get_epll(unsigned long baseclk) +{ + unsigned long result; + u32 epll0 = __raw_readl(S3C_EPLL_CON0); + u32 epll1 = __raw_readl(S3C_EPLL_CON1); + u32 mdiv, pdiv, sdiv, kdiv; + u64 tmp; + + mdiv = (epll0 >> S3C6400_EPLL_MDIV_SHIFT) & S3C6400_EPLL_MDIV_MASK; + pdiv = (epll0 >> S3C6400_EPLL_PDIV_SHIFT) & S3C6400_EPLL_PDIV_MASK; + sdiv = (epll0 >> S3C6400_EPLL_SDIV_SHIFT) & S3C6400_EPLL_SDIV_MASK; + kdiv = epll1 & S3C6400_EPLL_KDIV_MASK; + + /* We need to multiple baseclk by mdiv (the integer part) and kdiv + * which is in 2^16ths, so shift mdiv up (does not overflow) and + * add kdiv before multiplying. The use of tmp is to avoid any + * overflows before shifting bac down into result when multipling + * by the mdiv and kdiv pair. + */ + + tmp = baseclk; + tmp *= (mdiv << 16) + kdiv; + do_div(tmp, (pdiv << sdiv)); + result = tmp >> 16; + + return result; +} |