blob: 20baeaeba4cd0f85f156abe717a6bd45aea3de94 [file] [log] [blame]
/*
* linux/arch/mips/tx4938/common/prom.c
*
* common tx4938 memory interface
* Copyright (C) 2000-2001 Toshiba Corporation
*
* 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
* terms of the GNU General Public License version 2. This program is
* licensed "as is" without any warranty of any kind, whether express
* or implied.
*
* Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/io.h>
static unsigned int __init
tx4938_process_sdccr(u64 * addr)
{
u64 val;
unsigned int sdccr_ce;
unsigned int sdccr_rs;
unsigned int sdccr_cs;
unsigned int sdccr_mw;
unsigned int rs = 0;
unsigned int cs = 0;
unsigned int mw = 0;
unsigned int bc = 4;
unsigned int msize = 0;
val = ____raw_readq((void __iomem *)addr);
/* MVMCP -- need #defs for these bits masks */
sdccr_ce = ((val & (1 << 10)) >> 10);
sdccr_rs = ((val & (3 << 5)) >> 5);
sdccr_cs = ((val & (7 << 2)) >> 2);
sdccr_mw = ((val & (1 << 0)) >> 0);
if (sdccr_ce) {
switch (sdccr_rs) {
case 0:{
rs = 2048;
break;
}
case 1:{
rs = 4096;
break;
}
case 2:{
rs = 8192;
break;
}
default:{
rs = 0;
break;
}
}
switch (sdccr_cs) {
case 0:{
cs = 256;
break;
}
case 1:{
cs = 512;
break;
}
case 2:{
cs = 1024;
break;
}
case 3:{
cs = 2048;
break;
}
case 4:{
cs = 4096;
break;
}
default:{
cs = 0;
break;
}
}
switch (sdccr_mw) {
case 0:{
mw = 8;
break;
} /* 8 bytes = 64 bits */
case 1:{
mw = 4;
break;
} /* 4 bytes = 32 bits */
}
}
/* bytes per chip MB per chip bank count */
msize = (((rs * cs * mw) / (1024 * 1024)) * (bc));
/* MVMCP -- bc hard coded to 4 from table 9.3.1 */
/* boad supports bc=2 but no way to detect */
return (msize);
}
unsigned int __init
tx4938_get_mem_size(void)
{
unsigned int c0;
unsigned int c1;
unsigned int c2;
unsigned int c3;
unsigned int total;
/* MVMCP -- need #defs for these registers */
c0 = tx4938_process_sdccr((u64 *) 0xff1f8000);
c1 = tx4938_process_sdccr((u64 *) 0xff1f8008);
c2 = tx4938_process_sdccr((u64 *) 0xff1f8010);
c3 = tx4938_process_sdccr((u64 *) 0xff1f8018);
total = c0 + c1 + c2 + c3;
return (total);
}