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Diffstat (limited to 'board/incaip/incaip.c')
| -rw-r--r-- | board/incaip/incaip.c | 129 | 
1 files changed, 129 insertions, 0 deletions
| diff --git a/board/incaip/incaip.c b/board/incaip/incaip.c new file mode 100644 index 000000000..72f1c2151 --- /dev/null +++ b/board/incaip/incaip.c @@ -0,0 +1,129 @@ +/* + * (C) Copyright 2003 + * 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 <command.h> +#include <asm/addrspace.h> +#include <asm/inca-ip.h> + + +static ulong max_sdram_size(void) +{ +	/* The only supported SDRAM data width is 16bit. +	 */ +#define CFG_DW	2 + +	/* The only supported number of SDRAM banks is 4. +	 */ +#define CFG_NB	4 + +	ulong cfgpb0 = *INCA_IP_SDRAM_MC_CFGPB0; +	int   cols   = cfgpb0 & 0xF; +	int   rows   = (cfgpb0 & 0xF0) >> 4; +	ulong size   = (1 << (rows + cols)) * CFG_DW * CFG_NB; + +	return size; +} + +/* + * Check memory range for valid RAM. A simple memory test determines + * the actually available RAM size between addresses `base' and + * `base + maxsize'. Some (not all) hardware errors are detected: + * - short between address lines + * - short between data lines + */ + +static long int dram_size(long int *base, long int maxsize) +{ +	volatile long int *addr; +	ulong cnt, val; +	ulong save[32];			/* to make test non-destructive */ +	unsigned char i = 0; + +	for (cnt = (maxsize / sizeof (long)) >> 1; cnt > 0; cnt >>= 1) { +		addr = base + cnt;		/* pointer arith! */ + +		save[i++] = *addr; +		*addr = ~cnt; +	} + +	/* write 0 to base address */ +	addr = base; +	save[i] = *addr; +	*addr = 0; + +	/* check at base address */ +	if ((val = *addr) != 0) { +		*addr = save[i]; +		return (0); +	} + +	for (cnt = 1; cnt < maxsize / sizeof (long); cnt <<= 1) { +		addr = base + cnt;		/* pointer arith! */ + +		val = *addr; +		*addr = save[--i]; + +		if (val != (~cnt)) { +			return (cnt * sizeof (long)); +		} +	} +	return (maxsize); +} + +long int initdram(int board_type) +{ +	int   rows, cols, best_val = *INCA_IP_SDRAM_MC_CFGPB0; +	ulong size, max_size       = 0; +	ulong our_address; + +	asm volatile ("move %0, $25" : "=r" (our_address) :); + +		/* Can't probe for RAM size unless we are running from Flash. +		 */ +	if (PHYSADDR(our_address) < PHYSADDR(PHYS_FLASH_1)) +	{ +		return max_sdram_size(); +	} + +	for (cols = 0x8; cols <= 0xC; cols++) +	{ +		for (rows = 0xB; rows <= 0xD; rows++) +		{ +			*INCA_IP_SDRAM_MC_CFGPB0 = (0x14 << 8) | +			                           (rows << 4) | cols; +			size = dram_size((ulong *)CFG_SDRAM_BASE, +			                                     max_sdram_size()); + +			if (size > max_size) +			{ +				best_val = *INCA_IP_SDRAM_MC_CFGPB0; +				max_size = size; +			} +		} +	} + +	*INCA_IP_SDRAM_MC_CFGPB0 = best_val; +	return max_size; +} + |