diff --git a/board/delta/nand.c b/board/delta/nand.c
index e87d502b2519b4b7ae6000eda0dd8a470b9ca643..85a6ba291a0e312628b85e31ef9f2c0ff74adb45 100644
--- a/board/delta/nand.c
+++ b/board/delta/nand.c
@@ -193,7 +193,7 @@ static unsigned long get_delta(unsigned long start)
 static void wait_us(unsigned long us)
 {
 	unsigned long start = OSCR;
-	us *= OSCR_CLK_FREQ;
+	us = DIV_ROUND_UP(us * OSCR_CLK_FREQ, 1000);
 
 	while (get_delta(start) < us) {
 		/* do nothing */
@@ -214,9 +214,11 @@ static unsigned long dfc_wait_event(unsigned long event)
 	if(!event)
 		return 0xff000000;
 	else if(event & (NDSR_CS0_CMDD | NDSR_CS0_BBD))
-		timeout = CONFIG_SYS_NAND_PROG_ERASE_TO * OSCR_CLK_FREQ;
+		timeout = DIV_ROUND_UP(CONFIG_SYS_NAND_PROG_ERASE_TO
+					* OSCR_CLK_FREQ, 1000);
 	else
-		timeout = CONFIG_SYS_NAND_OTHER_TO * OSCR_CLK_FREQ;
+		timeout = DIV_ROUND_UP(CONFIG_SYS_NAND_OTHER_TO
+					* OSCR_CLK_FREQ, 1000);
 
 	while(1) {
 		ndsr = NDSR;
diff --git a/board/zylonite/nand.c b/board/zylonite/nand.c
index bec54cb72c945c55d99e9ab4d37f9a455194283a..7cad1ac049cbdc7c955cb88b5c3cfae84724d3f8 100644
--- a/board/zylonite/nand.c
+++ b/board/zylonite/nand.c
@@ -198,7 +198,7 @@ static unsigned long get_delta(unsigned long start)
 static void wait_us(unsigned long us)
 {
 	unsigned long start = OSCR;
-	us *= OSCR_CLK_FREQ;
+	us = DIV_ROUND_UP(us * OSCR_CLK_FREQ, 1000);
 
 	while (get_delta(start) < us) {
 		/* do nothing */
@@ -219,9 +219,11 @@ static unsigned long dfc_wait_event(unsigned long event)
 	if(!event)
 		return 0xff000000;
 	else if(event & (NDSR_CS0_CMDD | NDSR_CS0_BBD))
-		timeout = CONFIG_SYS_NAND_PROG_ERASE_TO * OSCR_CLK_FREQ;
+		timeout = DIV_ROUND_UP(CONFIG_SYS_NAND_PROG_ERASE_TO
+					* OSCR_CLK_FREQ, 1000);
 	else
-		timeout = CONFIG_SYS_NAND_OTHER_TO * OSCR_CLK_FREQ;
+		timeout = DIV_ROUND_UP(CONFIG_SYS_NAND_OTHER_TO
+					* OSCR_CLK_FREQ, 1000);
 
 	while(1) {
 		ndsr = NDSR;
diff --git a/include/asm-arm/arch-pxa/pxa-regs.h b/include/asm-arm/arch-pxa/pxa-regs.h
index f34af1972435d4c22ecac47825d5a3498114b026..a25d4c512a2ca9622cdfa609bbeb40a4d2dbbe5a 100644
--- a/include/asm-arm/arch-pxa/pxa-regs.h
+++ b/include/asm-arm/arch-pxa/pxa-regs.h
@@ -1094,7 +1094,7 @@ typedef void		(*ExcpHndlr) (void) ;
 #define OMCR10		__REG(0x40A000D8)  /* OS Match Control Register 10 */
 #define OMCR11		__REG(0x40A000DC)  /* OS Match Control Register 11 */
 
-#define OSCR_CLK_FREQ	 3.250		   /* MHz */
+#define OSCR_CLK_FREQ	 3250		   /* kHz = 3.25 MHz */
 #endif /* CONFIG_CPU_MONAHANS */
 
 #define OSSR_M4		(1 << 4)	/* Match status channel 4 */