u-boot/board/sbc8548/law.c
Paul Gortmaker 7e44f2b710 sbc8548: Make enabling SPD RAM configuration work
Previously, SPD configuration of RAM was non functional on
this board.  Now that the root cause is known (an i2c address
conflict), there is a simple end-user workaround - remove the
old slower local bus 128MB module and then SPD detection on the
main DDR2 memory module works fine.

We make the enablement of the LBC SDRAM support conditional on
being not SPD enabled.  We can revisit this dependency as the
hardware workaround becomes available.

Turning off LBC SDRAM support revealed a couple implict dependencies
in the tlb/law code that always expected an LBC SDRAM address.

This has been tested with the default 256MB module, a 512MB
a 1GB and a 2GB, of varying speeds, and the SPD autoconfiguration
worked fine in all cases.

The default configuration remains to go with the hard coded
DDR config, so the default build will continue to work on boards
where people don't bother to read the docs.  But the advantage
of going to the SPD config is that even the small default module
gets configured for CL3 instead of CL4.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2012-01-11 13:59:07 -06:00

72 lines
2.3 KiB
C

/*
* Copyright 2008 Freescale Semiconductor, Inc.
*
* (C) Copyright 2000
* 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
*/
#include <common.h>
#include <asm/fsl_law.h>
#include <asm/mmu.h>
/*
* LAW(Local Access Window) configuration:
*
* 0x0000_0000 0x0fff_ffff DDR 256M
* 0x8000_0000 0x9fff_ffff PCI1 MEM 512M
* 0xa000_0000 0xbfff_ffff PCIe MEM 512M
* 0xe000_0000 0xe000_ffff CCSR 1M
* 0xe200_0000 0xe27f_ffff PCI1 IO 8M
* 0xe280_0000 0xe2ff_ffff PCIe IO 8M
* 0xec00_0000 0xefff_ffff FLASH (2nd bank) 64M
* 0xf000_0000 0xf7ff_ffff SDRAM 128M
* 0xf8b0_0000 0xf80f_ffff EEPROM 1M
* 0xff80_0000 0xffff_ffff FLASH (boot bank) 8M
*
* If swapped CS0/CS6 via JP12+SW2.8:
* 0xef80_0000 0xefff_ffff FLASH (2nd bank) 8M
* 0xfc00_0000 0xffff_ffff FLASH (boot bank) 64M
*
* Notes:
* CCSRBAR and L2-as-SRAM don't need a configured Local Access Window.
* If flash is 8M at default position (last 8M), no LAW needed.
*/
struct law_entry law_table[] = {
#ifdef CONFIG_SYS_ALT_BOOT
SET_LAW(CONFIG_SYS_ALT_FLASH, LAW_SIZE_8M, LAW_TRGT_IF_LBC),
#else
SET_LAW(CONFIG_SYS_ALT_FLASH, LAW_SIZE_64M, LAW_TRGT_IF_LBC),
#endif
#ifndef CONFIG_SPD_EEPROM
SET_LAW(CONFIG_SYS_DDR_SDRAM_BASE, LAW_SIZE_256M, LAW_TRGT_IF_DDR),
#endif
#ifdef CONFIG_SYS_LBC_SDRAM_BASE
/* LBC window - maps 256M 0xf0000000 -> 0xffffffff */
SET_LAW(CONFIG_SYS_LBC_SDRAM_BASE, LAW_SIZE_256M, LAW_TRGT_IF_LBC),
#else
/* LBC window - maps 128M 0xf8000000 -> 0xffffffff */
SET_LAW(CONFIG_SYS_EPLD_BASE, LAW_SIZE_128M, LAW_TRGT_IF_LBC),
#endif
};
int num_law_entries = ARRAY_SIZE(law_table);