u-boot/cpu/mpc5xxx/speed.c

91 lines
2.3 KiB
C

/*
* (C) Copyright 2000-2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <mpc5xxx.h>
#include <asm/processor.h>
DECLARE_GLOBAL_DATA_PTR;
/* ------------------------------------------------------------------------- */
/* Bus-to-Core Multipliers */
static int bus2core[] = {
3, 2, 2, 2, 4, 4, 5, 9,
6, 11, 8, 10, 3, 12, 7, 0,
6, 5, 13, 2, 14, 4, 15, 9,
0, 11, 8, 10, 16, 12, 7, 0
};
/* ------------------------------------------------------------------------- */
/*
*
*/
int get_clocks (void)
{
ulong val, vco;
#if !defined(CFG_MPC5XXX_CLKIN)
#error clock measuring not implemented yet - define CFG_MPC5XXX_CLKIN
#endif
val = *(vu_long *)MPC5XXX_CDM_PORCFG;
if (val & (1 << 6)) {
vco = CFG_MPC5XXX_CLKIN * 12;
} else {
vco = CFG_MPC5XXX_CLKIN * 16;
}
if (val & (1 << 5)) {
gd->bus_clk = vco / 8;
} else {
gd->bus_clk = vco / 4;
}
gd->cpu_clk = gd->bus_clk * bus2core[val & 0x1f] / 2;
val = *(vu_long *)MPC5XXX_CDM_CFG;
if (val & (1 << 8)) {
gd->ipb_clk = gd->bus_clk / 2;
} else {
gd->ipb_clk = gd->bus_clk;
}
switch (val & 3) {
case 0: gd->pci_clk = gd->ipb_clk; break;
case 1: gd->pci_clk = gd->ipb_clk / 2; break;
default: gd->pci_clk = gd->bus_clk / 4; break;
}
return (0);
}
int prt_mpc5xxx_clks (void)
{
printf(" Bus %ld MHz, IPB %ld MHz, PCI %ld MHz\n",
gd->bus_clk / 1000000, gd->ipb_clk / 1000000,
gd->pci_clk / 1000000);
return (0);
}
/* ------------------------------------------------------------------------- */