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/*
* arch/powerpc/cpu/ppc4xx/40x_spd_sdram.c
* This SPD SDRAM detection code supports IBM/AMCC PPC44x cpu with a
* SDRAM controller. Those are all current 405 PPC's.
*
* (C) Copyright 2001
* Bill Hunter, Wave 7 Optics, williamhunter@attbi.com
*
* Based on code by:
*
* Kenneth Johansson ,Ericsson AB.
* kenneth.johansson@etx.ericsson.se
*
* hacked up by bill hunter. fixed so we could run before
* serial_init and console_init. previous version avoided this by
* running out of cache memory during serial/console init, then running
* this code later.
*
* (C) Copyright 2002
* Jun Gu, Artesyn Technology, jung@artesyncp.com
* Support for AMCC 440 based on OpenBIOS draminit.c from IBM.
*
* (C) Copyright 2005
* Stefan Roese, DENX Software Engineering, sr@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 <asm/processor.h>
#include <i2c.h>
#include <asm/ppc4xx.h>
#if defined(CONFIG_SPD_EEPROM) && !defined(CONFIG_440)
/*
* Set default values
*/
#ifndef CONFIG_SYS_I2C_SPEED
#define CONFIG_SYS_I2C_SPEED 50000
#endif
#define ONE_BILLION 1000000000
#define SDRAM0_CFG_DCE 0x80000000
#define SDRAM0_CFG_SRE 0x40000000
#define SDRAM0_CFG_PME 0x20000000
#define SDRAM0_CFG_MEMCHK 0x10000000
#define SDRAM0_CFG_REGEN 0x08000000
#define SDRAM0_CFG_ECCDD 0x00400000
#define SDRAM0_CFG_EMDULR 0x00200000
#define SDRAM0_CFG_DRW_SHIFT (31-6)
#define SDRAM0_CFG_BRPF_SHIFT (31-8)
#define SDRAM0_TR_CASL_SHIFT (31-8)
#define SDRAM0_TR_PTA_SHIFT (31-13)
#define SDRAM0_TR_CTP_SHIFT (31-15)
#define SDRAM0_TR_LDF_SHIFT (31-17)
#define SDRAM0_TR_RFTA_SHIFT (31-29)
#define SDRAM0_TR_RCD_SHIFT (31-31)
#define SDRAM0_RTR_SHIFT (31-15)
#define SDRAM0_ECCCFG_SHIFT (31-11)
/* SDRAM0_CFG enable macro */
#define SDRAM0_CFG_BRPF(x) ( ( x & 0x3)<< SDRAM0_CFG_BRPF_SHIFT )
#define SDRAM0_BXCR_SZ_MASK 0x000e0000
#define SDRAM0_BXCR_AM_MASK 0x0000e000
#define SDRAM0_BXCR_SZ_SHIFT (31-14)
#define SDRAM0_BXCR_AM_SHIFT (31-18)
#define SDRAM0_BXCR_SZ(x) ( (( x << SDRAM0_BXCR_SZ_SHIFT) & SDRAM0_BXCR_SZ_MASK) )
#define SDRAM0_BXCR_AM(x) ( (( x << SDRAM0_BXCR_AM_SHIFT) & SDRAM0_BXCR_AM_MASK) )
#ifdef CONFIG_SPDDRAM_SILENT
# define SPD_ERR(x) do { return 0; } while (0)
#else
# define SPD_ERR(x) do { printf(x); return(0); } while (0)
#endif
#define sdram_HZ_to_ns(hertz) (1000000000/(hertz))
/* function prototypes */
int spd_read(uint addr);
/*
* This function is reading data from the DIMM module EEPROM over the SPD bus
* and uses that to program the sdram controller.
*
* This works on boards that has the same schematics that the AMCC walnut has.
*
* Input: null for default I2C spd functions or a pointer to a custom function
* returning spd_data.
*/
long int spd_sdram(int(read_spd)(uint addr))
{
int tmp,row,col;
int total_size,bank_size,bank_code;
int ecc_on;
int mode;
int bank_cnt;
int sdram0_pmit=0x07c00000;
#ifndef CONFIG_405EP /* not on PPC405EP */
int sdram0_besr0 = -1;
int sdram0_besr1 = -1;
int sdram0_eccesr = -1;
#endif
int sdram0_ecccfg;
int sdram0_rtr=0;
int sdram0_tr=0;
int sdram0_b0cr;
int sdram0_b1cr;
int sdram0_b2cr;
int sdram0_b3cr;
int sdram0_cfg=0;
int t_rp;
int t_rcd;
int t_ras;
int t_rc;
int min_cas;
PPC4xx_SYS_INFO sys_info;
unsigned long bus_period_x_10;
/*
* get the board info
*/
get_sys_info(&sys_info);
bus_period_x_10 = ONE_BILLION / (sys_info.freqPLB / 10);
if (read_spd == 0){
read_spd=spd_read;
/*
* Make sure I2C controller is initialized
* before continuing.
*/
i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
}
/* Make shure we are using SDRAM */
if (read_spd(2) != 0x04) {
SPD_ERR("SDRAM - non SDRAM memory module found\n");
}
/* ------------------------------------------------------------------
* configure memory timing register
*
* data from DIMM:
* 27 IN Row Precharge Time ( t RP)
* 29 MIN RAS to CAS Delay ( t RCD)
* 127 Component and Clock Detail ,clk0-clk3, junction temp, CAS
* -------------------------------------------------------------------*/
/*
* first figure out which cas latency mode to use
* use the min supported mode
*/
tmp = read_spd(127) & 0x6;
if (tmp == 0x02) { /* only cas = 2 supported */
min_cas = 2;
/* t_ck = read_spd(9); */
/* t_ac = read_spd(10); */
} else if (tmp == 0x04) { /* only cas = 3 supported */
min_cas = 3;
/* t_ck = read_spd(9); */
/* t_ac = read_spd(10); */
} else if (tmp == 0x06) { /* 2,3 supported, so use 2 */
min_cas = 2;
/* t_ck = read_spd(23); */
/* t_ac = read_spd(24); */
} else {
SPD_ERR("SDRAM - unsupported CAS latency \n");
}
/* get some timing values, t_rp,t_rcd,t_ras,t_rc
*/
t_rp = read_spd(27);
t_rcd = read_spd(29);
t_ras = read_spd(30);
t_rc = t_ras + t_rp;
/* The following timing calcs subtract 1 before deviding.
* this has effect of using ceiling instead of floor rounding,
* and also subtracting 1 to convert number to reg value
*/
/* set up CASL */
sdram0_tr = (min_cas - 1) << SDRAM0_TR_CASL_SHIFT;
/* set up PTA */
sdram0_tr |= ((((t_rp - 1) * 10)/bus_period_x_10) & 0x3) << SDRAM0_TR_PTA_SHIFT;
/* set up CTP */
tmp = (((t_rc - t_rcd - t_rp -1) * 10) / bus_period_x_10) & 0x3;
if (tmp < 1)
tmp = 1;
sdram0_tr |= tmp << SDRAM0_TR_CTP_SHIFT;
/* set LDF = 2 cycles, reg value = 1 */
sdram0_tr |= 1 << SDRAM0_TR_LDF_SHIFT;
/* set RFTA = t_rfc/bus_period, use t_rfc = t_rc */
tmp = (((t_rc - 1) * 10) / bus_period_x_10) - 3;
if (tmp < 0)
tmp = 0;
if (tmp > 6)
tmp = 6;
sdram0_tr |= tmp << SDRAM0_TR_RFTA_SHIFT;
/* set RCD = t_rcd/bus_period*/
sdram0_tr |= ((((t_rcd - 1) * 10) / bus_period_x_10) &0x3) << SDRAM0_TR_RCD_SHIFT ;
/*------------------------------------------------------------------
* configure RTR register
* -------------------------------------------------------------------*/
row = read_spd(3);
col = read_spd(4);
tmp = read_spd(12) & 0x7f ; /* refresh type less self refresh bit */
switch (tmp) {
case 0x00:
tmp = 15625;
break;
case 0x01:
tmp = 15625 / 4;
break;
case 0x02:
tmp = 15625 / 2;
break;
case 0x03:
tmp = 15625 * 2;
break;
case 0x04:
tmp = 15625 * 4;
break;
case 0x05:
tmp = 15625 * 8;
break;
default:
SPD_ERR("SDRAM - Bad refresh period \n");
}
/* convert from nsec to bus cycles */
tmp = (tmp * 10) / bus_period_x_10;
sdram0_rtr = (tmp & 0x3ff8) << SDRAM0_RTR_SHIFT;
/*------------------------------------------------------------------
* determine the number of banks used
* -------------------------------------------------------------------*/
/* byte 7:6 is module data width */
if (read_spd(7) != 0)
SPD_ERR("SDRAM - unsupported module width\n");
tmp = read_spd(6);
if (tmp < 32)
SPD_ERR("SDRAM - unsupported module width\n");
else if (tmp < 64)
bank_cnt = 1; /* one bank per sdram side */
else if (tmp < 73)
bank_cnt = 2; /* need two banks per side */
else if (tmp < 161)
bank_cnt = 4; /* need four banks per side */
else
SPD_ERR("SDRAM - unsupported module width\n");
/* byte 5 is the module row count (refered to as dimm "sides") */
tmp = read_spd(5);
if (tmp == 1)
;
else if (tmp==2)
bank_cnt *= 2;
else if (tmp==4)
bank_cnt *= 4;
else
bank_cnt = 8; /* 8 is an error code */
if (bank_cnt > 4) /* we only have 4 banks to work with */
SPD_ERR("SDRAM - unsupported module rows for this width\n");
/* now check for ECC ability of module. We only support ECC
* on 32 bit wide devices with 8 bit ECC.
*/
if ((read_spd(11)==2) && (read_spd(6)==40) && (read_spd(14)==8)) {
sdram0_ecccfg = 0xf << SDRAM0_ECCCFG_SHIFT;
ecc_on = 1;
} else {
sdram0_ecccfg = 0;
ecc_on = 0;
}
/*------------------------------------------------------------------
* calculate total size
* -------------------------------------------------------------------*/
/* calculate total size and do sanity check */
tmp = read_spd(31);
total_size = 1 << 22; /* total_size = 4MB */
/* now multiply 4M by the smallest device row density */
/* note that we don't support asymetric rows */
while (((tmp & 0x0001) == 0) && (tmp != 0)) {
total_size = total_size << 1;
tmp = tmp >> 1;
}
total_size *= read_spd(5); /* mult by module rows (dimm sides) */
/*------------------------------------------------------------------
* map rows * cols * banks to a mode
* -------------------------------------------------------------------*/
switch (row) {
case 11:
switch (col) {
case 8:
mode=4; /* mode 5 */
break;
case 9:
case 10:
mode=0; /* mode 1 */
break;
default:
SPD_ERR("SDRAM - unsupported mode\n");
}
break;
case 12:
switch (col) {
case 8:
mode=3; /* mode 4 */
break;
case 9:
case 10:
mode=1; /* mode 2 */
break;
default:
SPD_ERR("SDRAM - unsupported mode\n");
}
break;
case 13:
switch (col) {
case 8:
mode=5; /* mode 6 */
break;
case 9:
case 10:
if (read_spd(17) == 2)
mode = 6; /* mode 7 */
else
mode = 2; /* mode 3 */
break;
case 11:
mode = 2; /* mode 3 */
break;
default:
SPD_ERR("SDRAM - unsupported mode\n");
}
break;
default:
SPD_ERR("SDRAM - unsupported mode\n");
}
/*------------------------------------------------------------------
* using the calculated values, compute the bank
* config register values.
* -------------------------------------------------------------------*/
sdram0_b1cr = 0;
sdram0_b2cr = 0;
sdram0_b3cr = 0;
/* compute the size of each bank */
bank_size = total_size / bank_cnt;
/* convert bank size to bank size code for ppc4xx
by takeing log2(bank_size) - 22 */
tmp = bank_size; /* start with tmp = bank_size */
bank_code = 0; /* and bank_code = 0 */
while (tmp > 1) { /* this takes log2 of tmp */
bank_code++; /* and stores result in bank_code */
tmp = tmp >> 1;
} /* bank_code is now log2(bank_size) */
bank_code -= 22; /* subtract 22 to get the code */
tmp = SDRAM0_BXCR_SZ(bank_code) | SDRAM0_BXCR_AM(mode) | 1;
sdram0_b0cr = (bank_size * 0) | tmp;
#ifndef CONFIG_405EP /* not on PPC405EP */
if (bank_cnt > 1)
sdram0_b2cr = (bank_size * 1) | tmp;
if (bank_cnt > 2)
sdram0_b1cr = (bank_size * 2) | tmp;
if (bank_cnt > 3)
sdram0_b3cr = (bank_size * 3) | tmp;
#else
/* PPC405EP chip only supports two SDRAM banks */
if (bank_cnt > 1)
sdram0_b1cr = (bank_size * 1) | tmp;
if (bank_cnt > 2)
total_size = 2 * bank_size;
#endif
/*
* enable sdram controller DCE=1
* enable burst read prefetch to 32 bytes BRPF=2
* leave other functions off
*/
/*------------------------------------------------------------------
* now that we've done our calculations, we are ready to
* program all the registers.
* -------------------------------------------------------------------*/
/* disable memcontroller so updates work */
mtsdram(SDRAM0_CFG, 0);
#ifndef CONFIG_405EP /* not on PPC405EP */
mtsdram(SDRAM0_BESR0, sdram0_besr0);
mtsdram(SDRAM0_BESR1, sdram0_besr1);
mtsdram(SDRAM0_ECCCFG, sdram0_ecccfg);
mtsdram(SDRAM0_ECCESR, sdram0_eccesr);
#endif
mtsdram(SDRAM0_RTR, sdram0_rtr);
mtsdram(SDRAM0_PMIT, sdram0_pmit);
mtsdram(SDRAM0_B0CR, sdram0_b0cr);
mtsdram(SDRAM0_B1CR, sdram0_b1cr);
#ifndef CONFIG_405EP /* not on PPC405EP */
mtsdram(SDRAM0_B2CR, sdram0_b2cr);
mtsdram(SDRAM0_B3CR, sdram0_b3cr);
#endif
mtsdram(SDRAM0_TR, sdram0_tr);
/* SDRAM have a power on delay, 500 micro should do */
udelay(500);
sdram0_cfg = SDRAM0_CFG_DCE | SDRAM0_CFG_BRPF(1) | SDRAM0_CFG_ECCDD | SDRAM0_CFG_EMDULR;
if (ecc_on)
sdram0_cfg |= SDRAM0_CFG_MEMCHK;
mtsdram(SDRAM0_CFG, sdram0_cfg);
return (total_size);
}
int spd_read(uint addr)
{
uchar data[2];
if (i2c_read(SPD_EEPROM_ADDRESS, addr, 1, data, 1) == 0)
return (int)data[0];
else
return 0;
}
#endif /* CONFIG_SPD_EEPROM */