u-boot/arch/blackfin/lib/clocks.c
Peter Tyser ea0364f1bb Move lib_$ARCH directories to arch/$ARCH/lib
Also move lib_$ARCH/config.mk to arch/$ARCH/config.mk

This change is intended to clean up the top-level directory structure
and more closely mimic Linux's directory organization.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:03 +02:00

77 lines
1.5 KiB
C

/*
* clocks.c - figure out sclk/cclk/vco and such
*
* Copyright (c) 2005-2008 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <common.h>
#include <asm/blackfin.h>
/* Get the voltage input multiplier */
static u_long cached_vco_pll_ctl, cached_vco;
u_long get_vco(void)
{
u_long msel;
u_long pll_ctl = bfin_read_PLL_CTL();
if (pll_ctl == cached_vco_pll_ctl)
return cached_vco;
else
cached_vco_pll_ctl = pll_ctl;
msel = (pll_ctl >> 9) & 0x3F;
if (0 == msel)
msel = 64;
cached_vco = CONFIG_CLKIN_HZ;
cached_vco >>= (1 & pll_ctl); /* DF bit */
cached_vco *= msel;
return cached_vco;
}
/* Get the Core clock */
static u_long cached_cclk_pll_div, cached_cclk;
u_long get_cclk(void)
{
u_long csel, ssel;
if (bfin_read_PLL_STAT() & 0x1)
return CONFIG_CLKIN_HZ;
ssel = bfin_read_PLL_DIV();
if (ssel == cached_cclk_pll_div)
return cached_cclk;
else
cached_cclk_pll_div = ssel;
csel = ((ssel >> 4) & 0x03);
ssel &= 0xf;
if (ssel && ssel < (1 << csel)) /* SCLK > CCLK */
cached_cclk = get_vco() / ssel;
else
cached_cclk = get_vco() >> csel;
return cached_cclk;
}
/* Get the System clock */
static u_long cached_sclk_pll_div, cached_sclk;
u_long get_sclk(void)
{
u_long ssel;
if (bfin_read_PLL_STAT() & 0x1)
return CONFIG_CLKIN_HZ;
ssel = bfin_read_PLL_DIV();
if (ssel == cached_sclk_pll_div)
return cached_sclk;
else
cached_sclk_pll_div = ssel;
ssel &= 0xf;
cached_sclk = get_vco() / ssel;
return cached_sclk;
}