blob: b8b7e1d884f80b92340e681f8578f5df25c78531 (
plain) (
tree)
|
|
/* arch/arm/plat-samsung/include/plat/pll6553x.h
* partially from arch/arm/mach-s3c64xx/include/mach/pll.h
*
* Copyright 2008 Openmoko, Inc.
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
* http://armlinux.simtec.co.uk/
*
* Samsung PLL6553x 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.
*/
/* S3C6400 and compatible (S3C2416, etc.) EPLL code */
#define PLL6553X_MDIV_MASK ((1 << (23-16)) - 1)
#define PLL6553X_PDIV_MASK ((1 << (13-8)) - 1)
#define PLL6553X_SDIV_MASK ((1 << (2-0)) - 1)
#define PLL6553X_MDIV_SHIFT (16)
#define PLL6553X_PDIV_SHIFT (8)
#define PLL6553X_SDIV_SHIFT (0)
#define PLL6553X_KDIV_MASK (0xffff)
static inline unsigned long s3c_get_pll6553x(unsigned long baseclk,
u32 pll0, u32 pll1)
{
unsigned long result;
u32 mdiv, pdiv, sdiv, kdiv;
u64 tmp;
mdiv = (pll0 >> PLL6553X_MDIV_SHIFT) & PLL6553X_MDIV_MASK;
pdiv = (pll0 >> PLL6553X_PDIV_SHIFT) & PLL6553X_PDIV_MASK;
sdiv = (pll0 >> PLL6553X_SDIV_SHIFT) & PLL6553X_SDIV_MASK;
kdiv = pll1 & PLL6553X_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;
}
|
