Sequential accesses to non-existent memory must be synchronized,

at least on G2 cores.

This fixes get_ram_size() problems on MPC5200 Rev. B boards.
This commit is contained in:
Wolfgang Denk 2006-11-06 17:06:36 +01:00 committed by Wolfgang Denk
parent ee58ea2689
commit 91650b3e4d
3 changed files with 37 additions and 1 deletions

View File

@ -27,6 +27,7 @@
#include <common.h>
#include <mpc5xxx.h>
#include <pci.h>
#include <asm/processor.h>
/* Two MT48LC8M32B2 for 32 MB */
/* #include "mt48lc8m32b2-6-7.h" */
@ -98,6 +99,7 @@ long int initdram (int board_type)
{
ulong dramsize = 0;
ulong dramsize2 = 0;
uint svr, pvr;
#ifndef CFG_RAMBOOT
ulong test1, test2;
@ -192,6 +194,23 @@ long int initdram (int board_type)
#endif /* CFG_RAMBOOT */
/*
* On MPC5200B we need to set the special configuration delay in the
* DDR controller. Please refer to Freescale's AN3221 "MPC5200B SDRAM
* Initialization and Configuration", 3.3.1 SDelay--MBAR + 0x0190:
*
* "The SDelay should be written to a value of 0x00000004. It is
* required to account for changes caused by normal wafer processing
* parameters."
*/
svr = get_svr();
pvr = get_pvr();
if ((SVR_MJREV(svr) >= 2) && (PVR_MAJ(pvr) == 1) &&
(PVR_MIN(pvr) == 4)) {
*(vu_long *)MPC5XXX_SDRAM_SDELAY = 0x04;
__asm__ volatile ("sync");
}
return dramsize + dramsize2;
}

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@ -21,6 +21,16 @@
* MA 02111-1307 USA
*/
#include <config.h>
#ifdef __PPC__
/*
* At least on G2 PowerPC cores, sequential accesses to non-existent
* memory must be synchronized.
*/
# include <asm/io.h> /* for sync() */
#else
# define sync() /* nothing */
#endif
/*
* Check memory range for valid RAM. A simple memory test determines
@ -38,20 +48,27 @@ long get_ram_size(volatile long *base, long maxsize)
for (cnt = (maxsize / sizeof (long)) >> 1; cnt > 0; cnt >>= 1) {
addr = base + cnt; /* pointer arith! */
sync ();
save[i++] = *addr;
sync ();
*addr = ~cnt;
}
addr = base;
sync ();
save[i] = *addr;
sync ();
*addr = 0;
sync ();
if ((val = *addr) != 0) {
/* Restore the original data before leaving the function.
*/
sync ();
*addr = save[i];
for (cnt = 1; cnt < maxsize / sizeof(long); cnt <<= 1) {
addr = base + cnt;
sync ();
*addr = save[--i];
}
return (0);

View File

@ -270,7 +270,7 @@ int misc_init_r (void);
void jumptable_init(void);
/* common/memsize.c */
int get_ram_size (volatile long *, long);
long get_ram_size (volatile long *, long);
/* $(BOARD)/$(BOARD).c */
void reset_phy (void);