cpu/mpc8xx/cpu.c - platform/external/u-boot - Gitiles

 /*
  * (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
  */

 /*
  * m8xx.c
  *
  * CPU specific code
  *
  * written or collected and sometimes rewritten by
  * Magnus Damm <damm@bitsmart.com>
  *
  * minor modifications by
  * Wolfgang Denk <wd@denx.de>
  */

 #include <common.h>
 #include <watchdog.h>
 #include <command.h>
 #include <mpc8xx.h>
 #include <asm/cache.h>

 static char *cpu_warning = "\n         " \
 	"*** Warning: CPU Core has Silicon Bugs -- Check the Errata ***";

 #if ((defined(CONFIG_MPC86x) || defined(CONFIG_MPC855)) && \
      !defined(CONFIG_MPC862))

 static int check_CPU (long clock, uint pvr, uint immr)
 {
 	char *id_str =
 # if defined(CONFIG_MPC855)
 	"PC855";
 # elif defined(CONFIG_MPC860P)
 	"PC860P";
 # else
 	NULL;
 # endif
 	volatile immap_t *immap = (immap_t *) (immr & 0xFFFF0000);
 	uint k, m;
 	char buf[32];
 	char pre = 'X';
 	char *mid = "xx";
 	char *suf;

 	/* the highest 16 bits should be 0x0050 for a 860 */

 	if ((pvr >> 16) != 0x0050)
 		return -1;

 	k = (immr << 16) | *((ushort *) & immap->im_cpm.cp_dparam[0xB0]);
 	m = 0;

 	/*
 	 * Some boards use sockets so different CPUs can be used.
 	 * We have to check chip version in run time.
 	 */
 	switch (k) {
 	case 0x00020001: pre = 'P'; suf = ""; break;
 	case 0x00030001: suf = ""; break;
 	case 0x00120003: suf = "A"; break;
 	case 0x00130003: suf = "A3"; break;

 	case 0x00200004: suf = "B"; break;

 	case 0x00300004: suf = "C"; break;
 	case 0x00310004: suf = "C1"; m = 1; break;

 	case 0x00200064: mid = "SR"; suf = "B"; break;
 	case 0x00300065: mid = "SR"; suf = "C"; break;
 	case 0x00310065: mid = "SR"; suf = "C1"; m = 1; break;
 	case 0x05010000: suf = "D3"; m = 1; break;
 	case 0x05020000: suf = "D4"; m = 1; break;
 		/* this value is not documented anywhere */
 	case 0x40000000: pre = 'P'; suf = "D"; m = 1; break;
 		/* MPC866P/MPC866T/MPC859T/MPC859DSL/MPC852T */
 	case 0x08000003: pre = 'M'; suf = ""; m = 1;
 		if (id_str == NULL)
 			id_str =
 # if defined(CONFIG_MPC852T)
 		"PC852T";
 # elif defined(CONFIG_MPC859T)
 		"PC859T";
 # elif defined(CONFIG_MPC859DSL)
 		"PC859DSL";
 # elif defined(CONFIG_MPC866T)
 		"PC866T";
 # else
 		"PC866x"; /* Unknown chip from MPC866 family */
 # endif
 		break;
 	case 0x09000000: pre = 'M'; mid = suf = ""; m = 1;
 		if (id_str == NULL)
 			id_str = "PC885"; /* 870/875/880/885 */
 		break;

 	default: suf = NULL; break;
 	}

 	if (id_str == NULL)
 		id_str = "PC86x";	/* Unknown 86x chip */
 	if (suf)
 		printf ("%c%s%sZPnn%s", pre, id_str, mid, suf);
 	else
 		printf ("unknown M%s (0x%08x)", id_str, k);


 #if defined(CFG_866_CPUCLK_MIN) && defined(CFG_866_CPUCLK_MAX)
 	printf (" at %s MHz [%d.%d...%d.%d MHz]\n       ",
 		strmhz (buf, clock),
 		CFG_866_CPUCLK_MIN / 1000000,
 		((CFG_866_CPUCLK_MIN % 1000000) + 50000) / 100000,
 		CFG_866_CPUCLK_MAX / 1000000,
 		((CFG_866_CPUCLK_MAX % 1000000) + 50000) / 100000
 	);
 #else
 	printf (" at %s MHz: ", strmhz (buf, clock));
 #endif
 	printf ("%u kB I-Cache %u kB D-Cache",
 		checkicache () >> 10,
 		checkdcache () >> 10
 	);

 	/* do we have a FEC (860T/P or 852/859/866)? */

 	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
 	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
 		printf (" FEC present");
 	}

 	if (!m) {
 		puts (cpu_warning);
 	}

 	putc ('\n');

 #ifdef DEBUG
 	if(clock != measure_gclk()) {
 	    printf ("clock %ldHz != %dHz\n", clock, measure_gclk());
 	}
 #endif

 	return 0;
 }

 #elif defined(CONFIG_MPC862)

 static int check_CPU (long clock, uint pvr, uint immr)
 {
 	volatile immap_t *immap = (immap_t *) (immr & 0xFFFF0000);
 	uint k, m;
 	char buf[32];
 	char pre = 'X';
 	char *mid = "xx";
 	char *suf;

 	/* the highest 16 bits should be 0x0050 for a 8xx */

 	if ((pvr >> 16) != 0x0050)
 		return -1;

 	k = (immr << 16) | *((ushort *) & immap->im_cpm.cp_dparam[0xB0]);
 	m = 0;

 	switch (k) {

 		/* this value is not documented anywhere */
 	case 0x06000000: mid = "P"; suf = "0"; break;
 	case 0x06010001: mid = "P"; suf = "A"; m = 1; break;
 	case 0x07000003: mid = "P"; suf = "B"; m = 1; break;
 	default: suf = NULL; break;
 	}

 	if (suf)
 		printf ("%cPC862%sZPnn%s", pre, mid, suf);
 	else
 		printf ("unknown MPC862 (0x%08x)", k);

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

 	printf (" %u kB I-Cache", checkicache () >> 10);
 	printf (" %u kB D-Cache", checkdcache () >> 10);

 	/* lets check and see if we're running on a 862T (or P?) */

 	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
 	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
 		printf (" FEC present");
 	}

 	if (!m) {
 		puts (cpu_warning);
 	}

 	putc ('\n');

 	return 0;
 }

 #elif defined(CONFIG_MPC823)

 static int check_CPU (long clock, uint pvr, uint immr)
 {
 	volatile immap_t *immap = (immap_t *) (immr & 0xFFFF0000);
 	uint k, m;
 	char buf[32];
 	char *suf;

 	/* the highest 16 bits should be 0x0050 for a 8xx */

 	if ((pvr >> 16) != 0x0050)
 		return -1;

 	k = (immr << 16) | *((ushort *) & immap->im_cpm.cp_dparam[0xB0]);
 	m = 0;

 	switch (k) {
 		/* MPC823 */
 	case 0x20000000: suf = "0"; break;
 	case 0x20010000: suf = "0.1"; break;
 	case 0x20020000: suf = "Z2/3"; break;
 	case 0x20020001: suf = "Z3"; break;
 	case 0x21000000: suf = "A"; break;
 	case 0x21010000: suf = "B"; m = 1; break;
 	case 0x21010001: suf = "B2"; m = 1; break;
 		/* MPC823E */
 	case 0x24010000: suf = NULL;
 			puts ("PPC823EZTnnB2");
 			m = 1;
 			break;
 	default:
 			suf = NULL;
 			printf ("unknown MPC823 (0x%08x)", k);
 			break;
 	}
 	if (suf)
 		printf ("PPC823ZTnn%s", suf);

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

 	printf (" %u kB I-Cache", checkicache () >> 10);
 	printf (" %u kB D-Cache", checkdcache () >> 10);

 	/* lets check and see if we're running on a 860T (or P?) */

 	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
 	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
 		puts (" FEC present");
 	}

 	if (!m) {
 		puts (cpu_warning);
 	}

 	putc ('\n');

 	return 0;
 }

 #elif defined(CONFIG_MPC850)

 static int check_CPU (long clock, uint pvr, uint immr)
 {
 	volatile immap_t *immap = (immap_t *) (immr & 0xFFFF0000);
 	uint k, m;
 	char buf[32];

 	/* the highest 16 bits should be 0x0050 for a 8xx */

 	if ((pvr >> 16) != 0x0050)
 		return -1;

 	k = (immr << 16) | *((ushort *) & immap->im_cpm.cp_dparam[0xB0]);
 	m = 0;

 	switch (k) {
 	case 0x20020001:
 		printf ("XPC850xxZT");
 		break;
 	case 0x21000065:
 		printf ("XPC850xxZTA");
 		break;
 	case 0x21010067:
 		printf ("XPC850xxZTB");
 		m = 1;
 		break;
 	case 0x21020068:
 		printf ("XPC850xxZTC");
 		m = 1;
 		break;
 	default:
 		printf ("unknown MPC850 (0x%08x)", k);
 	}
 	printf (" at %s MHz:", strmhz (buf, clock));

 	printf (" %u kB I-Cache", checkicache () >> 10);
 	printf (" %u kB D-Cache", checkdcache () >> 10);

 	/* lets check and see if we're running on a 850T (or P?) */

 	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
 	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
 		printf (" FEC present");
 	}

 	if (!m) {
 		puts (cpu_warning);
 	}

 	putc ('\n');

 	return 0;
 }
 #else
 #error CPU undefined
 #endif
 /* ------------------------------------------------------------------------- */

 int checkcpu (void)
 {
 	DECLARE_GLOBAL_DATA_PTR;

 	ulong clock = gd->cpu_clk;
 	uint immr = get_immr (0);	/* Return full IMMR contents */
 	uint pvr = get_pvr ();

 	puts ("CPU:   ");

 	/* 850 has PARTNUM 20 */
 	/* 801 has PARTNUM 10 */
 	return check_CPU (clock, pvr, immr);
 }

 /* ------------------------------------------------------------------------- */
 /* L1 i-cache                                                                */
 /* the standard 860 has 128 sets of 16 bytes in 2 ways (= 4 kB)              */
 /* the 860 P (plus) has 256 sets of 16 bytes in 4 ways (= 16 kB)             */

 int checkicache (void)
 {
 	volatile immap_t *immap = (immap_t *) CFG_IMMR;
 	volatile memctl8xx_t *memctl = &immap->im_memctl;
 	u32 cacheon = rd_ic_cst () & IDC_ENABLED;

 #ifdef CONFIG_IP86x
 	u32 k = memctl->memc_br1 & ~0x00007fff;	/* probe in flash memoryarea */
 #else
 	u32 k = memctl->memc_br0 & ~0x00007fff;	/* probe in flash memoryarea */
 #endif
 	u32 m;
 	u32 lines = -1;

 	wr_ic_cst (IDC_UNALL);
 	wr_ic_cst (IDC_INVALL);
 	wr_ic_cst (IDC_DISABLE);
 	__asm__ volatile ("isync");

 	while (!((m = rd_ic_cst ()) & IDC_CERR2)) {
 		wr_ic_adr (k);
 		wr_ic_cst (IDC_LDLCK);
 		__asm__ volatile ("isync");

 		lines++;
 		k += 0x10;				/* the number of bytes in a cacheline */
 	}

 	wr_ic_cst (IDC_UNALL);
 	wr_ic_cst (IDC_INVALL);

 	if (cacheon)
 		wr_ic_cst (IDC_ENABLE);
 	else
 		wr_ic_cst (IDC_DISABLE);

 	__asm__ volatile ("isync");

 	return lines << 4;
 };

 /* ------------------------------------------------------------------------- */
 /* L1 d-cache                                                                */
 /* the standard 860 has 128 sets of 16 bytes in 2 ways (= 4 kB)              */
 /* the 860 P (plus) has 256 sets of 16 bytes in 2 ways (= 8 kB)              */
 /* call with cache disabled                                                  */

 int checkdcache (void)
 {
 	volatile immap_t *immap = (immap_t *) CFG_IMMR;
 	volatile memctl8xx_t *memctl = &immap->im_memctl;
 	u32 cacheon = rd_dc_cst () & IDC_ENABLED;

 #ifdef CONFIG_IP86x
 	u32 k = memctl->memc_br1 & ~0x00007fff;	/* probe in flash memoryarea */
 #else
 	u32 k = memctl->memc_br0 & ~0x00007fff;	/* probe in flash memoryarea */
 #endif
 	u32 m;
 	u32 lines = -1;

 	wr_dc_cst (IDC_UNALL);
 	wr_dc_cst (IDC_INVALL);
 	wr_dc_cst (IDC_DISABLE);

 	while (!((m = rd_dc_cst ()) & IDC_CERR2)) {
 		wr_dc_adr (k);
 		wr_dc_cst (IDC_LDLCK);
 		lines++;
 		k += 0x10;	/* the number of bytes in a cacheline */
 	}

 	wr_dc_cst (IDC_UNALL);
 	wr_dc_cst (IDC_INVALL);

 	if (cacheon)
 		wr_dc_cst (IDC_ENABLE);
 	else
 		wr_dc_cst (IDC_DISABLE);

 	return lines << 4;
 };

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

 void upmconfig (uint upm, uint * table, uint size)
 {
 	uint i;
 	uint addr = 0;
 	volatile immap_t *immap = (immap_t *) CFG_IMMR;
 	volatile memctl8xx_t *memctl = &immap->im_memctl;

 	for (i = 0; i < size; i++) {
 		memctl->memc_mdr = table[i];	/* (16-15) */
 		memctl->memc_mcr = addr | upm;	/* (16-16) */
 		addr++;
 	}
 }

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

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

 	volatile immap_t *immap = (immap_t *) CFG_IMMR;

 	immap->im_clkrst.car_plprcr |= PLPRCR_CSR;	/* Checkstop Reset enable */

 	/* Interrupts and MMU off */
 	__asm__ volatile ("mtspr    81, 0");
 	__asm__ volatile ("mfmsr    %0":"=r" (msr));

 	msr &= ~0x1030;
 	__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.
 	 * "(ulong)-1" used to be a good choice for many systems...
 	 */
 	addr = CFG_MONITOR_BASE - sizeof (ulong);
 #endif
 	((void (*)(void)) addr) ();
 	return 1;
 }

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

 /*
  * Get timebase clock frequency (like cpu_clk in Hz)
  *
  * See sections 14.2 and 14.6 of the User's Manual
  */
 unsigned long get_tbclk (void)
 {
 	DECLARE_GLOBAL_DATA_PTR;

 	uint immr = get_immr (0);	/* Return full IMMR contents */
 	volatile immap_t *immap = (volatile immap_t *)(immr & 0xFFFF0000);
 	ulong oscclk, factor, pll;

 	if (immap->im_clkrst.car_sccr & SCCR_TBS) {
 		return (gd->cpu_clk / 16);
 	}

 	pll = immap->im_clkrst.car_plprcr;

 #define PLPRCR_val(a) ((pll & PLPRCR_ ## a ## _MSK) >> PLPRCR_ ## a ## _SHIFT)

 	/*
 	 * For newer PQ1 chips (MPC866/87x/88x families), PLL multiplication
 	 * factor is calculated as follows:
 	 *
 	 *		     MFN
 	 *	     MFI + -------
 	 *		   MFD + 1
 	 * factor =  -----------------
 	 *	     (PDF + 1) * 2^S
 	 *
 	 * For older chips, it's just MF field of PLPRCR plus one.
 	 */
 	if ((immr & 0x0FFF) >= MPC8xx_NEW_CLK) { /* MPC866/87x/88x series */
 		factor = (PLPRCR_val(MFI) + PLPRCR_val(MFN)/(PLPRCR_val(MFD)+1))/
 			(PLPRCR_val(PDF)+1) / (1<<PLPRCR_val(S));
 	} else {
 		factor = PLPRCR_val(MF)+1;
 	}

 	oscclk = gd->cpu_clk / factor;

 	if ((immap->im_clkrst.car_sccr & SCCR_RTSEL) == 0 || factor > 2) {
 		return (oscclk / 4);
 	}
 	return (oscclk / 16);
 }

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

 #if defined(CONFIG_WATCHDOG)
 void watchdog_reset (void)
 {
 	int re_enable = disable_interrupts ();

 	reset_8xx_watchdog ((immap_t *) CFG_IMMR);
 	if (re_enable)
 		enable_interrupts ();
 }

 void reset_8xx_watchdog (volatile immap_t * immr)
 {
 # if defined(CONFIG_LWMON)
 	/*
 	 * The LWMON board uses a MAX6301 Watchdog
 	 * with the trigger pin connected to port PA.7
 	 *
 	 * (The old board version used a MAX706TESA Watchdog, which
 	 * had to be handled exactly the same.)
 	 */
 # define WATCHDOG_BIT	0x0100
 	immr->im_ioport.iop_papar &= ~(WATCHDOG_BIT);	/* GPIO     */
 	immr->im_ioport.iop_padir |= WATCHDOG_BIT;	/* Output   */
 	immr->im_ioport.iop_paodr &= ~(WATCHDOG_BIT);	/* active output */

 	immr->im_ioport.iop_padat ^= WATCHDOG_BIT;	/* Toggle WDI   */
 # else
 	/*
 	 * All other boards use the MPC8xx Internal Watchdog
 	 */
 	immr->im_siu_conf.sc_swsr = 0x556c;	/* write magic1 */
 	immr->im_siu_conf.sc_swsr = 0xaa39;	/* write magic2 */
 # endif /* CONFIG_LWMON */
 }

 #endif /* CONFIG_WATCHDOG */

 /* ------------------------------------------------------------------------- */
	/*
	* (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
	*/

	/*
	* m8xx.c
	*
	* CPU specific code
	*
	* written or collected and sometimes rewritten by
	* Magnus Damm <damm@bitsmart.com>
	*
	* minor modifications by
	* Wolfgang Denk <wd@denx.de>
	*/

	#include <common.h>
	#include <watchdog.h>
	#include <command.h>
	#include <mpc8xx.h>
	#include <asm/cache.h>

	static char *cpu_warning = "\n " \
	"* Warning: CPU Core has Silicon Bugs -- Check the Errata *";

	#if ((defined(CONFIG_MPC86x) \|\| defined(CONFIG_MPC855)) && \
	!defined(CONFIG_MPC862))

	static int check_CPU (long clock, uint pvr, uint immr)
	{
	char *id_str =
	# if defined(CONFIG_MPC855)
	"PC855";
	# elif defined(CONFIG_MPC860P)
	"PC860P";
	# else
	NULL;
	# endif
	volatile immap_t immap = (immap_t ) (immr & 0xFFFF0000);
	uint k, m;
	char buf[32];
	char pre = 'X';
	char *mid = "xx";
	char *suf;

	/* the highest 16 bits should be 0x0050 for a 860 */

	if ((pvr >> 16) != 0x0050)
	return -1;

	k = (immr << 16) \| ((ushort ) & immap->im_cpm.cp_dparam[0xB0]);
	m = 0;

	/*
	* Some boards use sockets so different CPUs can be used.
	* We have to check chip version in run time.
	*/
	switch (k) {
	case 0x00020001: pre = 'P'; suf = ""; break;
	case 0x00030001: suf = ""; break;
	case 0x00120003: suf = "A"; break;
	case 0x00130003: suf = "A3"; break;

	case 0x00200004: suf = "B"; break;

	case 0x00300004: suf = "C"; break;
	case 0x00310004: suf = "C1"; m = 1; break;

	case 0x00200064: mid = "SR"; suf = "B"; break;
	case 0x00300065: mid = "SR"; suf = "C"; break;
	case 0x00310065: mid = "SR"; suf = "C1"; m = 1; break;
	case 0x05010000: suf = "D3"; m = 1; break;
	case 0x05020000: suf = "D4"; m = 1; break;
	/* this value is not documented anywhere */
	case 0x40000000: pre = 'P'; suf = "D"; m = 1; break;
	/* MPC866P/MPC866T/MPC859T/MPC859DSL/MPC852T */
	case 0x08000003: pre = 'M'; suf = ""; m = 1;
	if (id_str == NULL)
	id_str =
	# if defined(CONFIG_MPC852T)
	"PC852T";
	# elif defined(CONFIG_MPC859T)
	"PC859T";
	# elif defined(CONFIG_MPC859DSL)
	"PC859DSL";
	# elif defined(CONFIG_MPC866T)
	"PC866T";
	# else
	"PC866x"; /* Unknown chip from MPC866 family */
	# endif
	break;
	case 0x09000000: pre = 'M'; mid = suf = ""; m = 1;
	if (id_str == NULL)
	id_str = "PC885"; /* 870/875/880/885 */
	break;

	default: suf = NULL; break;
	}

	if (id_str == NULL)
	id_str = "PC86x"; /* Unknown 86x chip */
	if (suf)
	printf ("%c%s%sZPnn%s", pre, id_str, mid, suf);
	else
	printf ("unknown M%s (0x%08x)", id_str, k);


	#if defined(CFG_866_CPUCLK_MIN) && defined(CFG_866_CPUCLK_MAX)
	printf (" at %s MHz [%d.%d...%d.%d MHz]\n ",
	strmhz (buf, clock),
	CFG_866_CPUCLK_MIN / 1000000,
	((CFG_866_CPUCLK_MIN % 1000000) + 50000) / 100000,
	CFG_866_CPUCLK_MAX / 1000000,
	((CFG_866_CPUCLK_MAX % 1000000) + 50000) / 100000
	);
	#else
	printf (" at %s MHz: ", strmhz (buf, clock));
	#endif
	printf ("%u kB I-Cache %u kB D-Cache",
	checkicache () >> 10,
	checkdcache () >> 10
	);

	/* do we have a FEC (860T/P or 852/859/866)? */

	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
	printf (" FEC present");
	}

	if (!m) {
	puts (cpu_warning);
	}

	putc ('\n');

	#ifdef DEBUG
	if(clock != measure_gclk()) {
	printf ("clock %ldHz != %dHz\n", clock, measure_gclk());
	}
	#endif

	return 0;
	}

	#elif defined(CONFIG_MPC862)

	static int check_CPU (long clock, uint pvr, uint immr)
	{
	volatile immap_t immap = (immap_t ) (immr & 0xFFFF0000);
	uint k, m;
	char buf[32];
	char pre = 'X';
	char *mid = "xx";
	char *suf;

	/* the highest 16 bits should be 0x0050 for a 8xx */

	if ((pvr >> 16) != 0x0050)
	return -1;

	k = (immr << 16) \| ((ushort ) & immap->im_cpm.cp_dparam[0xB0]);
	m = 0;

	switch (k) {

	/* this value is not documented anywhere */
	case 0x06000000: mid = "P"; suf = "0"; break;
	case 0x06010001: mid = "P"; suf = "A"; m = 1; break;
	case 0x07000003: mid = "P"; suf = "B"; m = 1; break;
	default: suf = NULL; break;
	}

	if (suf)
	printf ("%cPC862%sZPnn%s", pre, mid, suf);
	else
	printf ("unknown MPC862 (0x%08x)", k);

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

	printf (" %u kB I-Cache", checkicache () >> 10);
	printf (" %u kB D-Cache", checkdcache () >> 10);

	/* lets check and see if we're running on a 862T (or P?) */

	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
	printf (" FEC present");
	}

	if (!m) {
	puts (cpu_warning);
	}

	putc ('\n');

	return 0;
	}

	#elif defined(CONFIG_MPC823)

	static int check_CPU (long clock, uint pvr, uint immr)
	{
	volatile immap_t immap = (immap_t ) (immr & 0xFFFF0000);
	uint k, m;
	char buf[32];
	char *suf;

	/* the highest 16 bits should be 0x0050 for a 8xx */

	if ((pvr >> 16) != 0x0050)
	return -1;

	k = (immr << 16) \| ((ushort ) & immap->im_cpm.cp_dparam[0xB0]);
	m = 0;

	switch (k) {
	/* MPC823 */
	case 0x20000000: suf = "0"; break;
	case 0x20010000: suf = "0.1"; break;
	case 0x20020000: suf = "Z2/3"; break;
	case 0x20020001: suf = "Z3"; break;
	case 0x21000000: suf = "A"; break;
	case 0x21010000: suf = "B"; m = 1; break;
	case 0x21010001: suf = "B2"; m = 1; break;
	/* MPC823E */
	case 0x24010000: suf = NULL;
	puts ("PPC823EZTnnB2");
	m = 1;
	break;
	default:
	suf = NULL;
	printf ("unknown MPC823 (0x%08x)", k);
	break;
	}
	if (suf)
	printf ("PPC823ZTnn%s", suf);

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

	printf (" %u kB I-Cache", checkicache () >> 10);
	printf (" %u kB D-Cache", checkdcache () >> 10);

	/* lets check and see if we're running on a 860T (or P?) */

	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
	puts (" FEC present");
	}

	if (!m) {
	puts (cpu_warning);
	}

	putc ('\n');

	return 0;
	}

	#elif defined(CONFIG_MPC850)

	static int check_CPU (long clock, uint pvr, uint immr)
	{
	volatile immap_t immap = (immap_t ) (immr & 0xFFFF0000);
	uint k, m;
	char buf[32];

	/* the highest 16 bits should be 0x0050 for a 8xx */

	if ((pvr >> 16) != 0x0050)
	return -1;

	k = (immr << 16) \| ((ushort ) & immap->im_cpm.cp_dparam[0xB0]);
	m = 0;

	switch (k) {
	case 0x20020001:
	printf ("XPC850xxZT");
	break;
	case 0x21000065:
	printf ("XPC850xxZTA");
	break;
	case 0x21010067:
	printf ("XPC850xxZTB");
	m = 1;
	break;
	case 0x21020068:
	printf ("XPC850xxZTC");
	m = 1;
	break;
	default:
	printf ("unknown MPC850 (0x%08x)", k);
	}
	printf (" at %s MHz:", strmhz (buf, clock));

	printf (" %u kB I-Cache", checkicache () >> 10);
	printf (" %u kB D-Cache", checkdcache () >> 10);

	/* lets check and see if we're running on a 850T (or P?) */

	immap->im_cpm.cp_fec.fec_addr_low = 0x12345678;
	if (immap->im_cpm.cp_fec.fec_addr_low == 0x12345678) {
	printf (" FEC present");
	}

	if (!m) {
	puts (cpu_warning);
	}

	putc ('\n');

	return 0;
	}
	#else
	#error CPU undefined
	#endif
	/* ------------------------------------------------------------------------- */

	int checkcpu (void)
	{
	DECLARE_GLOBAL_DATA_PTR;

	ulong clock = gd->cpu_clk;
	uint immr = get_immr (0); /* Return full IMMR contents */
	uint pvr = get_pvr ();

	puts ("CPU: ");

	/* 850 has PARTNUM 20 */
	/* 801 has PARTNUM 10 */
	return check_CPU (clock, pvr, immr);
	}

	/* ------------------------------------------------------------------------- */
	/* L1 i-cache */
	/* the standard 860 has 128 sets of 16 bytes in 2 ways (= 4 kB) */
	/* the 860 P (plus) has 256 sets of 16 bytes in 4 ways (= 16 kB) */

	int checkicache (void)
	{
	volatile immap_t immap = (immap_t ) CFG_IMMR;
	volatile memctl8xx_t *memctl = &immap->im_memctl;
	u32 cacheon = rd_ic_cst () & IDC_ENABLED;

	#ifdef CONFIG_IP86x
	u32 k = memctl->memc_br1 & ~0x00007fff; /* probe in flash memoryarea */
	#else
	u32 k = memctl->memc_br0 & ~0x00007fff; /* probe in flash memoryarea */
	#endif
	u32 m;
	u32 lines = -1;

	wr_ic_cst (IDC_UNALL);
	wr_ic_cst (IDC_INVALL);
	wr_ic_cst (IDC_DISABLE);
	__asm__ volatile ("isync");

	while (!((m = rd_ic_cst ()) & IDC_CERR2)) {
	wr_ic_adr (k);
	wr_ic_cst (IDC_LDLCK);
	__asm__ volatile ("isync");

	lines++;
	k += 0x10; /* the number of bytes in a cacheline */
	}

	wr_ic_cst (IDC_UNALL);
	wr_ic_cst (IDC_INVALL);

	if (cacheon)
	wr_ic_cst (IDC_ENABLE);
	else
	wr_ic_cst (IDC_DISABLE);

	__asm__ volatile ("isync");

	return lines << 4;
	};

	/* ------------------------------------------------------------------------- */
	/* L1 d-cache */
	/* the standard 860 has 128 sets of 16 bytes in 2 ways (= 4 kB) */
	/* the 860 P (plus) has 256 sets of 16 bytes in 2 ways (= 8 kB) */
	/* call with cache disabled */

	int checkdcache (void)
	{
	volatile immap_t immap = (immap_t ) CFG_IMMR;
	volatile memctl8xx_t *memctl = &immap->im_memctl;
	u32 cacheon = rd_dc_cst () & IDC_ENABLED;

	#ifdef CONFIG_IP86x
	u32 k = memctl->memc_br1 & ~0x00007fff; /* probe in flash memoryarea */
	#else
	u32 k = memctl->memc_br0 & ~0x00007fff; /* probe in flash memoryarea */
	#endif
	u32 m;
	u32 lines = -1;

	wr_dc_cst (IDC_UNALL);
	wr_dc_cst (IDC_INVALL);
	wr_dc_cst (IDC_DISABLE);

	while (!((m = rd_dc_cst ()) & IDC_CERR2)) {
	wr_dc_adr (k);
	wr_dc_cst (IDC_LDLCK);
	lines++;
	k += 0x10; /* the number of bytes in a cacheline */
	}

	wr_dc_cst (IDC_UNALL);
	wr_dc_cst (IDC_INVALL);

	if (cacheon)
	wr_dc_cst (IDC_ENABLE);
	else
	wr_dc_cst (IDC_DISABLE);

	return lines << 4;
	};

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

	void upmconfig (uint upm, uint * table, uint size)
	{
	uint i;
	uint addr = 0;
	volatile immap_t immap = (immap_t ) CFG_IMMR;
	volatile memctl8xx_t *memctl = &immap->im_memctl;

	for (i = 0; i < size; i++) {
	memctl->memc_mdr = table[i]; /* (16-15) */
	memctl->memc_mcr = addr \| upm; /* (16-16) */
	addr++;
	}
	}

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

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

	volatile immap_t immap = (immap_t ) CFG_IMMR;

	immap->im_clkrst.car_plprcr \|= PLPRCR_CSR; /* Checkstop Reset enable */

	/* Interrupts and MMU off */
	__asm__ volatile ("mtspr 81, 0");
	__asm__ volatile ("mfmsr %0":"=r" (msr));

	msr &= ~0x1030;
	__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.
	* "(ulong)-1" used to be a good choice for many systems...
	*/
	addr = CFG_MONITOR_BASE - sizeof (ulong);
	#endif
	((void (*)(void)) addr) ();
	return 1;
	}

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

	/*
	* Get timebase clock frequency (like cpu_clk in Hz)
	*
	* See sections 14.2 and 14.6 of the User's Manual
	*/
	unsigned long get_tbclk (void)
	{
	DECLARE_GLOBAL_DATA_PTR;

	uint immr = get_immr (0); /* Return full IMMR contents */
	volatile immap_t immap = (volatile immap_t )(immr & 0xFFFF0000);
	ulong oscclk, factor, pll;

	if (immap->im_clkrst.car_sccr & SCCR_TBS) {
	return (gd->cpu_clk / 16);
	}

	pll = immap->im_clkrst.car_plprcr;

	#define PLPRCR_val(a) ((pll & PLPRCR_ ## a ## _MSK) >> PLPRCR_ ## a ## _SHIFT)

	/*
	* For newer PQ1 chips (MPC866/87x/88x families), PLL multiplication
	* factor is calculated as follows:
	*
	* MFN
	* MFI + -------
	* MFD + 1
	* factor = -----------------
	* (PDF + 1) * 2^S
	*
	* For older chips, it's just MF field of PLPRCR plus one.
	*/
	if ((immr & 0x0FFF) >= MPC8xx_NEW_CLK) { /* MPC866/87x/88x series */
	factor = (PLPRCR_val(MFI) + PLPRCR_val(MFN)/(PLPRCR_val(MFD)+1))/
	(PLPRCR_val(PDF)+1) / (1<<PLPRCR_val(S));
	} else {
	factor = PLPRCR_val(MF)+1;
	}

	oscclk = gd->cpu_clk / factor;

	if ((immap->im_clkrst.car_sccr & SCCR_RTSEL) == 0 \|\| factor > 2) {
	return (oscclk / 4);
	}
	return (oscclk / 16);
	}

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

	#if defined(CONFIG_WATCHDOG)
	void watchdog_reset (void)
	{
	int re_enable = disable_interrupts ();

	reset_8xx_watchdog ((immap_t *) CFG_IMMR);
	if (re_enable)
	enable_interrupts ();
	}

	void reset_8xx_watchdog (volatile immap_t * immr)
	{
	# if defined(CONFIG_LWMON)
	/*
	* The LWMON board uses a MAX6301 Watchdog
	* with the trigger pin connected to port PA.7
	*
	* (The old board version used a MAX706TESA Watchdog, which
	* had to be handled exactly the same.)
	*/
	# define WATCHDOG_BIT 0x0100
	immr->im_ioport.iop_papar &= ~(WATCHDOG_BIT); /* GPIO */
	immr->im_ioport.iop_padir \|= WATCHDOG_BIT; /* Output */
	immr->im_ioport.iop_paodr &= ~(WATCHDOG_BIT); /* active output */

	immr->im_ioport.iop_padat ^= WATCHDOG_BIT; /* Toggle WDI */
	# else
	/*
	* All other boards use the MPC8xx Internal Watchdog
	*/
	immr->im_siu_conf.sc_swsr = 0x556c; /* write magic1 */
	immr->im_siu_conf.sc_swsr = 0xaa39; /* write magic2 */
	# endif /* CONFIG_LWMON */
	}

	#endif /* CONFIG_WATCHDOG */

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