diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index 308bbe291d8f..75bceee9b9a5 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -294,6 +294,11 @@ config BFIN_KERNEL_CLOCK
 	  are also not changed, and the Bootloader does 100% of the hardware
 	  configuration.
 
+config MEM_SIZE
+	int "SDRAM Memory Size in MBytes"
+	depends on BFIN_KERNEL_CLOCK
+	default 64
+
 config MEM_ADD_WIDTH
 	int "Memory Address Width"
 	depends on BFIN_KERNEL_CLOCK
@@ -373,6 +378,14 @@ config SCLK_DIV
 	  This can be between 1 and 15
 	  System Clock = (PLL frequency) / (this setting)
 
+config MAX_MEM_SIZE
+	int "Max SDRAM Memory Size in MBytes"
+	depends on !BFIN_KERNEL_CLOCK && !MPU
+	default 512
+	help
+	  This is the max memory size that the kernel will create CPLB
+	  tables for.  Your system will not be able to handle any more.
+
 #
 # Max & Min Speeds for various Chips
 #
@@ -441,19 +454,6 @@ source kernel/time/Kconfig
 
 comment "Memory Setup"
 
-config MEM_SIZE
-	int "SDRAM Memory Size in MBytes"
-	default  32 if BFIN533_EZKIT
-	default  64 if BFIN527_EZKIT
-	default  64 if BFIN537_STAMP
-	default  64 if BFIN548_EZKIT
-	default  64 if BFIN561_EZKIT
-	default 128 if BFIN533_STAMP
-	default  64 if PNAV10
-	default  32 if H8606_HVSISTEMAS
-	default  64 if BFIN548_BLUETECHNIX_CM
-	default  64 if BFIN532_IP0X
-
 choice
 	prompt "DDR SDRAM Chip Type"
 	depends on (BFIN548_EZKIT || BFIN548_BLUETECHNIX_CM)
diff --git a/arch/blackfin/kernel/cplb-nompu/cplbinit.c b/arch/blackfin/kernel/cplb-nompu/cplbinit.c
index f271f39d5655..917325bfbd84 100644
--- a/arch/blackfin/kernel/cplb-nompu/cplbinit.c
+++ b/arch/blackfin/kernel/cplb-nompu/cplbinit.c
@@ -26,6 +26,12 @@
 #include <asm/cplb.h>
 #include <asm/cplbinit.h>
 
+#ifdef CONFIG_MAX_MEM_SIZE
+# define CPLB_MEM CONFIG_MAX_MEM_SIZE
+#else
+# define CPLB_MEM CONFIG_MEM_SIZE
+#endif
+
 /*
 * Number of required data CPLB switchtable entries
 * MEMSIZE / 4 (we mostly install 4M page size CPLBs
@@ -35,7 +41,7 @@
 * 1 for CONFIG_DEBUG_HUNT_FOR_ZERO
 * 1 for ASYNC Memory
 */
-#define MAX_SWITCH_D_CPLBS (((CONFIG_MEM_SIZE / 4) + 16 + 1 + 1 + 1 \
+#define MAX_SWITCH_D_CPLBS (((CPLB_MEM / 4) + 16 + 1 + 1 + 1 \
 				 + ASYNC_MEMORY_CPLB_COVERAGE) * 2)
 
 /*
@@ -46,7 +52,7 @@
 * possibly 1 for L2 Instruction Memory
 * 1 for CONFIG_DEBUG_HUNT_FOR_ZERO
 */
-#define MAX_SWITCH_I_CPLBS (((CONFIG_MEM_SIZE / 4) + 12 + 1 + 1 + 1) * 2)
+#define MAX_SWITCH_I_CPLBS (((CPLB_MEM / 4) + 12 + 1 + 1 + 1) * 2)
 
 
 u_long icplb_table[MAX_CPLBS + 1];
diff --git a/arch/blackfin/kernel/setup.c b/arch/blackfin/kernel/setup.c
index c2f3e73ba25a..d6668328be72 100644
--- a/arch/blackfin/kernel/setup.c
+++ b/arch/blackfin/kernel/setup.c
@@ -649,6 +649,49 @@ static __init void setup_bootmem_allocator(void)
 		BOOTMEM_DEFAULT);
 }
 
+#define EBSZ_TO_MEG(ebsz) \
+({ \
+	int meg = 0; \
+	switch (ebsz & 0xf) { \
+		case 0x1: meg =  16; break; \
+		case 0x3: meg =  32; break; \
+		case 0x5: meg =  64; break; \
+		case 0x7: meg = 128; break; \
+		case 0x9: meg = 256; break; \
+		case 0xb: meg = 512; break; \
+	} \
+	meg; \
+})
+static inline int __init get_mem_size(void)
+{
+#ifdef CONFIG_MEM_SIZE
+	return CONFIG_MEM_SIZE;
+#else
+# if defined(EBIU_SDBCTL)
+#  if defined(BF561_FAMILY)
+	int ret = 0;
+	u32 sdbctl = bfin_read_EBIU_SDBCTL();
+	ret += EBSZ_TO_MEG(sdbctl >>  0);
+	ret += EBSZ_TO_MEG(sdbctl >>  8);
+	ret += EBSZ_TO_MEG(sdbctl >> 16);
+	ret += EBSZ_TO_MEG(sdbctl >> 24);
+	return ret;
+#  else
+	return EBSZ_TO_MEG(bfin_read_EBIU_SDBCTL());
+#  endif
+# elif defined(EBIU_DDRCTL1)
+	switch (bfin_read_EBIU_DDRCTL1() & 0xc0000) {
+		case DEVSZ_64:  return 64;
+		case DEVSZ_128: return 128;
+		case DEVSZ_256: return 256;
+		case DEVSZ_512: return 512;
+		default:        return 0;
+	}
+# endif
+#endif
+	BUG();
+}
+
 void __init setup_arch(char **cmdline_p)
 {
 	unsigned long sclk, cclk;
@@ -669,7 +712,7 @@ void __init setup_arch(char **cmdline_p)
 
 	/* setup memory defaults from the user config */
 	physical_mem_end = 0;
-	_ramend = CONFIG_MEM_SIZE * 1024 * 1024;
+	_ramend = get_mem_size() * 1024 * 1024;
 
 	memset(&bfin_memmap, 0, sizeof(bfin_memmap));
 
diff --git a/arch/blackfin/mach-common/arch_checks.c b/arch/blackfin/mach-common/arch_checks.c
index 2f6ce397780f..caaab49e9cfa 100644
--- a/arch/blackfin/mach-common/arch_checks.c
+++ b/arch/blackfin/mach-common/arch_checks.c
@@ -54,7 +54,8 @@
 
 #endif /* CONFIG_BFIN_KERNEL_CLOCK */
 
+#ifdef CONFIG_MEM_SIZE
 #if (CONFIG_MEM_SIZE % 4)
 #error "SDRAM mem size must be multible of 4MB"
 #endif
-
+#endif