kernel-fxtec-pro1x/arch/arm/plat-s3c64xx/include/plat/pll.h
Kyungmin Park 11e3bd0923 [ARM] S3C64XX: Mask the pll values correctly
Correct the PLL field masks to ensure the PLL functions return the
right value.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
[ben-linux@fluff.org: improve the description text]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-12-16 10:19:13 +00:00

74 lines
2.2 KiB
C

/* 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)) - 1)
#define S3C6400_PLL_PDIV_MASK ((1 << (13-8+1)) - 1)
#define S3C6400_PLL_SDIV_MASK ((1 << (2-0+1)) - 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;
}