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.
diff --git a/board/mcc200/mcc200.c b/board/mcc200/mcc200.c
index 71a691b..8b475c6 100644
--- a/board/mcc200/mcc200.c
+++ b/board/mcc200/mcc200.c
@@ -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 @@
{
ulong dramsize = 0;
ulong dramsize2 = 0;
+ uint svr, pvr;
#ifndef CFG_RAMBOOT
ulong test1, test2;
@@ -192,6 +194,23 @@
#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;
}
diff --git a/common/memsize.c b/common/memsize.c
index dbc812d..6c275c9 100644
--- a/common/memsize.c
+++ b/common/memsize.c
@@ -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 @@
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);
diff --git a/include/common.h b/include/common.h
index 349d5cf..ac78d1c 100644
--- a/include/common.h
+++ b/include/common.h
@@ -270,7 +270,7 @@
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);