u-boot-brain/board/freescale/mpc8349emds/ddr.c
York Sun 712cf7ab0b powerpc/mpc8xxx: Merge entries in DDR speed table
It is not necessary to keep multiple entries for the same setting in DDR
speed tables. Merge them for smaller tables. Also restructure the tables
for smaller size. Cleanup some typedefs.

Enforce strict checking for speed table. If DIMM is running at higher than
known speed, try to use the highest speed setting. If rank is unknown, it
has to panic.

Removed ODT overriding for P2020DS as it is not necessary.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-10-09 17:57:53 -05:00

118 lines
3.3 KiB
C

/*
* Copyright 2011 Freescale Semiconductor, Inc.
*
* 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/fsl_ddr_sdram.h>
#include <asm/fsl_ddr_dimm_params.h>
struct board_specific_parameters {
u32 n_ranks;
u32 datarate_mhz_high;
u32 clk_adjust;
u32 cpo;
u32 write_data_delay;
u32 force_2T;
};
/*
* This table contains all valid speeds we want to override with board
* specific parameters. datarate_mhz_high values need to be in ascending order
* for each n_ranks group.
*/
static const struct board_specific_parameters udimm0[] = {
/*
* memory controller 0
* num| hi| clk| cpo|wrdata|2T
* ranks| mhz|adjst| | delay|
*/
{2, 300, 4, 4, 2, 0},
{2, 365, 4, 6, 2, 0},
{2, 450, 4, 7, 2, 0},
{2, 850, 4, 31, 2, 0},
{1, 300, 4, 4, 2, 0},
{1, 365, 4, 6, 2, 0},
{1, 450, 4, 7, 2, 0},
{1, 850, 4, 31, 2, 0},
{}
};
void fsl_ddr_board_options(memctl_options_t *popts,
dimm_params_t *pdimm,
unsigned int ctrl_num)
{
const struct board_specific_parameters *pbsp, *pbsp_highest = NULL;
unsigned int i;
ulong ddr_freq;
if (ctrl_num != 0) /* we have only one controller */
return;
for (i = 0; i < CONFIG_DIMM_SLOTS_PER_CTLR; i++) {
if (pdimm[i].n_ranks)
break;
}
if (i >= CONFIG_DIMM_SLOTS_PER_CTLR) /* no DIMM */
return;
pbsp = udimm0;
/* Get clk_adjust, cpo, write_data_delay,2T, according to the board ddr
* freqency and n_banks specified in board_specific_parameters table.
*/
ddr_freq = get_ddr_freq(0) / 1000000;
while (pbsp->datarate_mhz_high) {
if (pbsp->n_ranks == pdimm[i].n_ranks) {
if (ddr_freq <= pbsp->datarate_mhz_high) {
popts->clk_adjust = pbsp->clk_adjust;
popts->cpo_override = pbsp->cpo;
popts->write_data_delay =
pbsp->write_data_delay;
popts->twoT_en = pbsp->force_2T;
goto found;
}
pbsp_highest = pbsp;
}
pbsp++;
}
if (pbsp_highest) {
printf("Error: board specific timing not found "
"for data rate %lu MT/s!\n"
"Trying to use the highest speed (%u) parameters\n",
ddr_freq, pbsp_highest->datarate_mhz_high);
popts->clk_adjust = pbsp_highest->clk_adjust;
popts->cpo_override = pbsp_highest->cpo;
popts->write_data_delay = pbsp_highest->write_data_delay;
popts->twoT_en = pbsp_highest->force_2T;
} else {
panic("DIMM is not supported by this board");
}
found:
/*
* Factors to consider for half-strength driver enable:
* - number of DIMMs installed
*/
popts->half_strength_driver_enable = 0;
popts->DQS_config = 0; /* only true DQS signal is used on board */
}