uboot-vybrid_public/cpu/mpc5xxx/cpu.c

/*
 * (C) Copyright 2000-2003
 * 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
 */

/*
 * CPU specific code for the MPC5xxx CPUs
 */

#include <common.h>
#include <watchdog.h>
#include <command.h>
#include <mpc5xxx.h>
#include <asm/processor.h>

int checkcpu (void)
{
	DECLARE_GLOBAL_DATA_PTR;

	ulong clock = gd->cpu_clk;
	char buf[32];

	puts ("CPU:   ");

	printf (CPU_ID_STR);

	printf (" (JTAG ID %08lx)", *(vu_long *)MPC5XXX_CDM_JTAGID);

	printf (" at %s MHz\n", strmhz (buf, clock));

	return 0;
}

/* ------------------------------------------------------------------------- */

int
do_reset (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
{
	ulong msr, addr;

	*(vu_long *)MPC5XXX_CDM_SRESET &= ~(1 << 16);	/* Checkstop Reset enable */

	/* Interrupts and MMU off */
	__asm__ __volatile__ ("mfmsr    %0":"=r" (msr):);

	msr &= ~(MSR_ME | MSR_EE | MSR_IR | MSR_DR);
	__asm__ __volatile__ ("mtmsr    %0"::"r" (msr));

	/*
	 * Trying to execute the next instruction at a non-existing address
	 * should cause a machine check, resulting in reset
	 */
#ifdef CFG_RESET_ADDRESS
	addr = CFG_RESET_ADDRESS;
#else
	/*
	 * note: when CFG_MONITOR_BASE points to a RAM address, CFG_MONITOR_BASE
	 * - sizeof (ulong) is usually a valid address. Better pick an address
	 * known to be invalid on your system and assign it to CFG_RESET_ADDRESS.
	 */
	addr = CFG_MONITOR_BASE - sizeof (ulong);
#endif
	((void (*)(void)) addr) ();
	return 1;

}

/* ------------------------------------------------------------------------- */

/*
 * Get timebase clock frequency (like cpu_clk in Hz)
 *
 */
unsigned long get_tbclk (void)
{
	DECLARE_GLOBAL_DATA_PTR;

	ulong tbclk;

	tbclk = (gd->bus_clk + 3L) / 4L;

	return (tbclk);
}

/* ------------------------------------------------------------------------- */