mip405.c

gumstiz u-boot loader in linux

/*
 * (C) Copyright 2001
 * Denis Peter, MPL AG Switzerland, [e-mail]
 *
 * 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
 *
 *
 * TODO: clean-up
 */

/*
 * How do I program the SDRAM Timing Register (SDRAM0_TR) for a specific SDRAM or DIMM?
 *
 * As an example, consider a case where PC133 memory with CAS Latency equal to 2 is being
 * used with a 200MHz 405GP. For a typical 128Mb, PC133 SDRAM, the relevant minimum
 * parameters from the datasheet are:
 * Tclk = 7.5ns (CL = 2)
 * Trp = 15ns
 * Trc = 60ns
 * Trcd = 15ns
 * Trfc = 66ns
 *
 * If we are operating the 405GP with the MemClk output frequency set to 100 MHZ, the clock
 * period is 10ns and the parameters needed for the Timing Register are:
 * CASL = CL = 2 clock cycles
 * PTA = Trp = 15ns / 10ns = 2 clock cycles
 * CTP = Trc - Trcd - Trp = (60ns - 15ns - 15ns) / 10ns= 3 clock cycles
 * LDF = 2 clock cycles (but can be extended to meet board-level timing)
 * RFTA = Trfc = 66ns / 10ns= 7 clock cycles
 * RCD = Trcd = 15ns / 10ns= 2 clock cycles
 *
 * The actual bit settings in the register would be:
 *
 * CASL = 0b01
 * PTA = 0b01
 * CTP = 0b10
 * LDF = 0b01
 * RFTA = 0b011
 * RCD = 0b01
 *
 * If Trfc is not specified in the datasheet for PC100 or PC133 memory, set RFTA = Trc
 * instead. Figure 24 in the PC SDRAM Specification Rev. 1.7 shows refresh to active delay
 * defined as Trc rather than Trfc.
 * When using DIMM modules, most but not all of the required timing parameters can be read
 * from the Serial Presence Detect (SPD) EEPROM on the module. Specifically, Trc and Trfc
 * are not available from the EEPROM
 */

#include <common.h>
#include "mip405.h"
#include <asm/processor.h>
#include <405gp_i2c.h>
#include <miiphy.h>
#include "../common/common_util.h"
#include <i2c.h>
#include <rtc.h>
extern block_dev_desc_t * scsi_get_dev(int dev);
extern block_dev_desc_t * ide_get_dev(int dev);

#undef SDRAM_DEBUG
#define ENABLE_ECC /* for ecc boards */
#define FALSE           0
#define TRUE            1

/* stdlib.h causes some compatibility problems; should fixe these! -- wd */
#ifndef __ldiv_t_defined
typedef struct {
	long int quot;		/* Quotient	*/
	long int rem;		/* Remainder	*/
} ldiv_t;
extern ldiv_t ldiv (long int __numer, long int __denom);
# define __ldiv_t_defined	1
#endif


#define PLD_PART_REG 		PER_PLD_ADDR + 0
#define PLD_VERS_REG 		PER_PLD_ADDR + 1
#define PLD_BOARD_CFG_REG 	PER_PLD_ADDR + 2
#define PLD_IRQ_REG 		PER_PLD_ADDR + 3
#define PLD_COM_MODE_REG 	PER_PLD_ADDR + 4
#define PLD_EXT_CONF_REG 	PER_PLD_ADDR + 5

#define MEGA_BYTE (1024*1024)

typedef struct {
	unsigned char boardtype; /* Board revision and Population Options */
	unsigned char cal;		/* cas Latency (will be programmend as cal-1) */
	unsigned char trp;		/* datain27 in clocks */
	unsigned char trcd;		/* datain29 in clocks */
	unsigned char tras;		/* datain30 in clocks */
	unsigned char tctp;		/* tras - trcd in clocks */
	unsigned char am;		/* Address Mod (will be programmed as am-1) */
	unsigned char sz;		/* log binary => Size = (4MByte<<sz) 5 = 128, 4 = 64, 3 = 32, 2 = 16, 1=8 */
	unsigned char ecc;		/* if true, ecc is enabled */
} sdram_t;
#if defined(CONFIG_MIP405T)
const sdram_t sdram_table[] = {
	{ 0x0F,	/* MIP405T Rev A, 64MByte -1 Board */
		3,	/* Case Latenty = 3 */
		3,	/* trp 20ns / 7.5 ns datain[27] */
		3,	/* trcd 20ns /7.5 ns (datain[29]) */
		6,	/* tras 44ns /7.5 ns  (datain[30]) */
		4,	/* tcpt 44 - 20ns = 24ns */
		2,	/* Address Mode = 2 (12x9x4) */
		3,	/* size value (32MByte) */
		0},	/* ECC disabled */
	{ 0xff, /* terminator */
	  0xff,
	  0xff,
	  0xff,
	  0xff,
	  0xff,
	  0xff,
	  0xff }
};
#else
const sdram_t sdram_table[] = {
	{ 0x0f,	/* Rev A, 128MByte -1 Board */
		3,	/* Case Latenty = 3 */
		3,	/* trp 20ns / 7.5 ns datain[27] */
		3,	/* trcd 20ns /7.5 ns (datain[29]) */
		6,	/* tras 44ns /7.5 ns  (datain[30]) */
		4,	/* tcpt 44 - 20ns = 24ns */
		3,	/* Address Mode = 3 */
		5,	/* size value */
		1},	/* ECC enabled */
	{ 0x07,	/* Rev A, 64MByte -2 Board */
		3,	/* Case Latenty = 3 */
		3,	/* trp 20ns / 7.5 ns datain[27] */
		3,	/* trcd 20ns /7.5 ns (datain[29]) */
		6,	/* tras 44ns /7.5 ns  (datain[30]) */
		4,	/* tcpt 44 - 20ns = 24ns */
		2,	/* Address Mode = 2 */
		4,	/* size value */
		1},	/* ECC enabled */
	{ 0x03,	/* Rev A, 128MByte -4 Board */
		3,	/* Case Latenty = 3 */
		3,	/* trp 20ns / 7.5 ns datain[27] */
		3,	/* trcd 20ns /7.5 ns (datain[29]) */
		6,	/* tras 44ns /7.5 ns  (datain[30]) */
		4,	/* tcpt 44 - 20ns = 24ns */
		3,	/* Address Mode = 3 */
		5,	/* size value */
		1},	/* ECC enabled */
	{ 0x1f,	/* Rev B, 128MByte -3 Board */
		3,	/* Case Latenty = 3 */
		3,	/* trp 20ns / 7.5 ns datain[27] */
		3,	/* trcd 20ns /7.5 ns (datain[29]) */
		6,	/* tras 44ns /7.5 ns  (datain[30]) */
		4,	/* tcpt 44 - 20ns = 24ns */
		3,	/* Address Mode = 3 */
		5,	/* size value */
		1},	/* ECC enabled */
	{ 0x2f,	/* Rev C, 128MByte -3 Board */
		3,	/* Case Latenty = 3 */
		3,	/* trp 20ns / 7.5 ns datain[27] */
		3,	/* trcd 20ns /7.5 ns (datain[29]) */
		6,	/* tras 44ns /7.5 ns  (datain[30]) */
		4,	/* tcpt 44 - 20ns = 24ns */
		3,	/* Address Mode = 3 */
		5,	/* size value */
		1},	/* ECC enabled */
	{ 0xff, /* terminator */
	  0xff,
	  0xff,
	  0xff,
	  0xff,
	  0xff,
	  0xff,
	  0xff }
};
#endif /*CONFIG_MIP405T */
void SDRAM_err (const char *s)
{
#ifndef SDRAM_DEBUG
	DECLARE_GLOBAL_DATA_PTR;

	(void) get_clocks ();
	gd->baudrate = 9600;
	serial_init ();
#endif
	serial_puts ("\n");
	serial_puts (s);
	serial_puts ("\n enable SDRAM_DEBUG for more info\n");
	for (;;);
}


unsigned char get_board_revcfg (void)
{
	out8 (PER_BOARD_ADDR, 0);
	return (in8 (PER_BOARD_ADDR));
}


#ifdef SDRAM_DEBUG

void write_hex (unsigned char i)
{
	char cc;

	cc = i >> 4;
	cc &= 0xf;
	if (cc > 9)
		serial_putc (cc + 55);
	else
		serial_putc (cc + 48);
	cc = i & 0xf;
	if (cc > 9)
		serial_putc (cc + 55);
	else
		serial_putc (cc + 48);
}

void write_4hex (unsigned long val)
{
	write_hex ((unsigned char) (val >> 24));
	write_hex ((unsigned char) (val >> 16));
	write_hex ((unsigned char) (val >> 8));
	write_hex ((unsigned char) val);
}

#endif


int init_sdram (void)
{
	DECLARE_GLOBAL_DATA_PTR;

	unsigned long	tmp, baseaddr;
	unsigned short	i;
	unsigned char	trp_clocks,
			trcd_clocks,
			tras_clocks,
			trc_clocks,
			tctp_clocks;
	unsigned char	cal_val;
	unsigned char	bc;
	unsigned long	sdram_tim, sdram_bank;

	/*i2c_init (CFG_I2C_SPEED, CFG_I2C_SLAVE);*/
	(void) get_clocks ();
	gd->baudrate = 9600;
	serial_init ();
	/* set up the pld */
	mtdcr (ebccfga, pb7ap);
	mtdcr (ebccfgd, PLD_AP);
	mtdcr (ebccfga, pb7cr);
	mtdcr (ebccfgd, PLD_CR);
	/* THIS IS OBSOLETE */
	/* set up the board rev reg*/
	mtdcr (ebccfga, pb5ap);
	mtdcr (ebccfgd, BOARD_AP);
	mtdcr (ebccfga, pb5cr);
	mtdcr (ebccfgd, BOARD_CR);
#ifdef SDRAM_DEBUG
	/* get all informations from PLD */
	serial_puts ("\nPLD Part  0x");
	bc = in8 (PLD_PART_REG);
	write_hex (bc);
	serial_puts ("\nPLD Vers  0x");
	bc = in8 (PLD_VERS_REG);
	write_hex (bc);
	serial_puts ("\nBoard Rev 0x");
	bc = in8 (PLD_BOARD_CFG_REG);
	write_hex (bc);
	serial_puts ("\n");
#endif
	/* check board */
	bc = in8 (PLD_PART_REG);
#if defined(CONFIG_MIP405T)
	if((bc & 0x80)==0)
		SDRAM_err ("U-Boot configured for a MIP405T not for a MIP405!!!\n");
#else
	if((bc & 0x80)==0x80)
		SDRAM_err ("U-Boot configured for a MIP405 not for a MIP405T!!!\n");
#endif
	/* set-up the chipselect machine */
	mtdcr (ebccfga, pb0cr);		/* get cs0 config reg */
	tmp = mfdcr (ebccfgd);
	if ((tmp & 0x00002000) == 0) {
		/* MPS Boot, set up the flash */
		mtdcr (ebccfga, pb1ap);
		mtdcr (ebccfgd, FLASH_AP);
		mtdcr (ebccfga, pb1cr);
		mtdcr (ebccfgd, FLASH_CR);
	} else {
		/* Flash boot, set up the MPS */
		mtdcr (ebccfga, pb1ap);
		mtdcr (ebccfgd, MPS_AP);
		mtdcr (ebccfga, pb1cr);
		mtdcr (ebccfgd, MPS_CR);
	}
	/* set up UART0 (CS2) and UART1 (CS3) */
	mtdcr (ebccfga, pb2ap);
	mtdcr (ebccfgd, UART0_AP);
	mtdcr (ebccfga, pb2cr);
	mtdcr (ebccfgd, UART0_CR);
	mtdcr (ebccfga, pb3ap);
	mtdcr (ebccfgd, UART1_AP);
	mtdcr (ebccfga, pb3cr);
	mtdcr (ebccfgd, UART1_CR);
	bc = in8 (PLD_BOARD_CFG_REG);
#ifdef SDRAM_DEBUG
	serial_puts ("\nstart SDRAM Setup\n");
	serial_puts ("\nBoard Rev: ");
	write_hex (bc);
	serial_puts ("\n");
#endif
	i = 0;
	baseaddr = CFG_SDRAM_BASE;
	while (sdram_table[i].sz != 0xff) {
		if (sdram_table[i].boardtype == bc)
			break;
		i++;
	}
	if (sdram_table[i].boardtype != bc)
		SDRAM_err ("No SDRAM table found for this board!!!\n");
#ifdef SDRAM_DEBUG
	serial_puts (" found table ");
	write_hex (i);
	serial_puts (" \n");
#endif
	/* since the ECC initialisation needs some time,
	 * we show that we're alive
	 */
	if (sdram_table[i].ecc)
		serial_puts ("\nInitializing SDRAM, Please stand by");
	cal_val = sdram_table[i].cal - 1;	/* Cas Latency */
	trp_clocks = sdram_table[i].trp;	/* 20ns / 7.5 ns datain[27] */
	trcd_clocks = sdram_table[i].trcd;	/* 20ns /7.5 ns (datain[29]) */
	tras_clocks = sdram_table[i].tras;	/* 44ns /7.5 ns  (datain[30]) */
	/* ctp = ((trp + tras) - trp - trcd) => tras - trcd */
	tctp_clocks = sdram_table[i].tctp;	/* 44 - 20ns = 24ns */
	/* trc_clocks is sum of trp_clocks + tras_clocks */
	trc_clocks = trp_clocks + tras_clocks;
	/* get SDRAM timing register */
	mtdcr (memcfga, mem_sdtr1);
	sdram_tim = mfdcr (memcfgd) & ~0x018FC01F;
	/* insert CASL value */
	sdram_tim |= ((unsigned long) (cal_val)) << 23;
	/* insert PTA value */
	sdram_tim |= ((unsigned long) (trp_clocks - 1)) << 18;
	/* insert CTP value */
	sdram_tim |=
			((unsigned long) (trc_clocks - trp_clocks -
							  trcd_clocks)) << 16;
	/* insert LDF (always 01) */
	sdram_tim |= ((unsigned long) 0x01) << 14;
	/* insert RFTA value */
	sdram_tim |= ((unsigned long) (trc_clocks - 4)) << 2;
	/* insert RCD value */
	sdram_tim |= ((unsigned long) (trcd_clocks - 1)) << 0;

	tmp = ((unsigned long) (sdram_table[i].am - 1) << 13);	/* AM = 3 */
	/* insert SZ value; */
	tmp |= ((unsigned long) sdram_table[i].sz << 17);
	/* get SDRAM bank 0 register */
	mtdcr (memcfga, mem_mb0cf);
	sdram_bank = mfdcr (memcfgd) & ~0xFFCEE001;
	sdram_bank |= (baseaddr | tmp | 0x01);

#ifdef SDRAM_DEBUG
	serial_puts ("sdtr: ");
	write_4hex (sdram_tim);
	serial_puts ("\n");
#endif

	/* write SDRAM timing register */
	mtdcr (memcfga, mem_sdtr1);
	mtdcr (memcfgd, sdram_tim);

#ifdef SDRAM_DEBUG
	serial_puts ("mb0cf: ");
	write_4hex (sdram_bank);
	serial_puts ("\n");
#endif

	/* write SDRAM bank 0 register */
	mtdcr (memcfga, mem_mb0cf);
	mtdcr (memcfgd, sdram_bank);

	if (get_bus_freq (tmp) > 110000000) {	/* > 110MHz */
		/* get SDRAM refresh interval register */
		mtdcr (memcfga, mem_rtr);
		tmp = mfdcr (memcfgd) & ~0x3FF80000;
		tmp |= 0x07F00000;
	} else {
		/* get SDRAM refresh interval register */
		mtdcr (memcfga, mem_rtr);
		tmp = mfdcr (memcfgd) & ~0x3FF80000;
		tmp |= 0x05F00000;
	}
	/* write SDRAM refresh interval register */
	mtdcr (memcfga, mem_rtr);