Blackfin arch: Fix Bug - Kernel does not boot if re-program clocks

On BF561 EBIU_SDGCTL bit 31 controls the SDRAM external data
path width, typically set 0 for a 32-bit bus width. On other
Blackfin derivatives this bit should be set by default.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/mach-common/clocks-init.c b/arch/blackfin/mach-common/clocks-init.c
index 5d182ab..9dddb6f 100644
--- a/arch/blackfin/mach-common/clocks-init.c
+++ b/arch/blackfin/mach-common/clocks-init.c
@@ -14,6 +14,7 @@
 #include <asm/clocks.h>
 #include <asm/mem_init.h>
 
+#define SDGCTL_WIDTH (1 << 31)	/* SDRAM external data path width */
 #define PLL_CTL_VAL \
 	(((CONFIG_VCO_MULT & 63) << 9) | CLKIN_HALF | \
 	 (PLL_BYPASS << 8) | (ANOMALY_05000265 ? 0x8000 : 0))
@@ -76,7 +77,7 @@
 	bfin_write_PLL_DIV(CONFIG_CCLK_ACT_DIV | CONFIG_SCLK_DIV);
 #ifdef EBIU_SDGCTL
 	bfin_write_EBIU_SDRRC(mem_SDRRC);
-	bfin_write_EBIU_SDGCTL(mem_SDGCTL);
+	bfin_write_EBIU_SDGCTL((bfin_read_EBIU_SDGCTL() & SDGCTL_WIDTH) | mem_SDGCTL);
 #else
 	bfin_write_EBIU_RSTCTL(bfin_read_EBIU_RSTCTL() & ~(SRREQ));
 	do_sync();