ppc: Move CONFIG_MAX_MEM_MAPPED to common config.h

Moved CONFIG_MAX_MEM_MAPPED to the asm/config.h so its kept consistent
between the two current users (lib_ppc/board.c, 44x SPD DDR2).

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Stefan Roese <sr@denx.de>
diff --git a/cpu/ppc4xx/44x_spd_ddr2.c b/cpu/ppc4xx/44x_spd_ddr2.c
index b40e4b1..1e49571 100644
--- a/cpu/ppc4xx/44x_spd_ddr2.c
+++ b/cpu/ppc4xx/44x_spd_ddr2.c
@@ -160,9 +160,6 @@
  * SDRAM. This is because we only map the first 2GB on such systems, and therefore
  * the ECC parity byte of the remaining area can't be written.
  */
-#ifndef CONFIG_MAX_MEM_MAPPED
-#define CONFIG_MAX_MEM_MAPPED	((phys_size_t)2 << 30)
-#endif
 
 /*
  * Board-specific Platform code can reimplement spd_ddr_init_hang () if needed
diff --git a/include/asm-ppc/config.h b/include/asm-ppc/config.h
index 049c44e..6d27cb1 100644
--- a/include/asm-ppc/config.h
+++ b/include/asm-ppc/config.h
@@ -21,4 +21,12 @@
 #ifndef _ASM_CONFIG_H_
 #define _ASM_CONFIG_H_
 
+#ifndef CONFIG_MAX_MEM_MAPPED
+#if defined(CONFIG_SDRAM_PPC4xx_IBM_DDR2) && defined(CONFIG_SPD_EEPROM)
+#define CONFIG_MAX_MEM_MAPPED	((phys_size_t)2 << 30)
+#else
+#define CONFIG_MAX_MEM_MAPPED (256 << 20)
+#endif
+#endif
+
 #endif
diff --git a/lib_ppc/board.c b/lib_ppc/board.c
index 2262bb4..d90607d 100644
--- a/lib_ppc/board.c
+++ b/lib_ppc/board.c
@@ -352,9 +352,6 @@
 	NULL,			/* Terminate this list */
 };
 
-#ifndef CONFIG_MAX_MEM_MAPPED
-#define CONFIG_MAX_MEM_MAPPED (256 << 20)
-#endif
 ulong get_effective_memsize(void)
 {
 #ifndef	CONFIG_VERY_BIG_RAM