nb/intel/sandybridge: Reduce the scope of get_CWL()

It is only used once, and can thus be moved to the same file.

Change-Id: I4ee0621449da7fa1970a475d5a2f6e66546357ea
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47485
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
diff --git a/src/northbridge/intel/sandybridge/raminit_common.c b/src/northbridge/intel/sandybridge/raminit_common.c
index 3ab8df2..60a218b 100644
--- a/src/northbridge/intel/sandybridge/raminit_common.c
+++ b/src/northbridge/intel/sandybridge/raminit_common.c
@@ -80,41 +80,6 @@
 	return reg;
 }
 
-/* CAS write latency. To be programmed in MR2. See DDR3 SPEC for MR2 documentation. */
-u8 get_CWL(u32 tCK)
-{
-	/* Get CWL based on tCK using the following rule */
-	switch (tCK) {
-	case TCK_1333MHZ:
-		return 12;
-
-	case TCK_1200MHZ:
-	case TCK_1100MHZ:
-		return 11;
-
-	case TCK_1066MHZ:
-	case TCK_1000MHZ:
-		return 10;
-
-	case TCK_933MHZ:
-	case TCK_900MHZ:
-		return 9;
-
-	case TCK_800MHZ:
-	case TCK_700MHZ:
-		return 8;
-
-	case TCK_666MHZ:
-		return 7;
-
-	case TCK_533MHZ:
-		return 6;
-
-	default:
-		return 5;
-	}
-}
-
 void dram_find_common_params(ramctr_timing *ctrl)
 {
 	size_t valid_dimms;
diff --git a/src/northbridge/intel/sandybridge/raminit_common.h b/src/northbridge/intel/sandybridge/raminit_common.h
index 32f2b44..5b08ce5 100644
--- a/src/northbridge/intel/sandybridge/raminit_common.h
+++ b/src/northbridge/intel/sandybridge/raminit_common.h
@@ -227,7 +227,6 @@
 #define MAKE_ERR		((channel << 16) | (slotrank << 8) | 1)
 #define GET_ERR_CHANNEL(x)	(x >> 16)
 
-u8 get_CWL(u32 tCK);
 void dram_mrscommands(ramctr_timing *ctrl);
 void program_timings(ramctr_timing *ctrl, int channel);
 void dram_find_common_params(ramctr_timing *ctrl);
diff --git a/src/northbridge/intel/sandybridge/raminit_native.c b/src/northbridge/intel/sandybridge/raminit_native.c
index 326197b..844e69a 100644
--- a/src/northbridge/intel/sandybridge/raminit_native.c
+++ b/src/northbridge/intel/sandybridge/raminit_native.c
@@ -42,6 +42,41 @@
 	die("Unsupported CPU or base frequency.");
 }
 
+/* CAS write latency. To be programmed in MR2. See DDR3 SPEC for MR2 documentation. */
+static u8 get_CWL(u32 tCK)
+{
+	/* Get CWL based on tCK using the following rule */
+	switch (tCK) {
+	case TCK_1333MHZ:
+		return 12;
+
+	case TCK_1200MHZ:
+	case TCK_1100MHZ:
+		return 11;
+
+	case TCK_1066MHZ:
+	case TCK_1000MHZ:
+		return 10;
+
+	case TCK_933MHZ:
+	case TCK_900MHZ:
+		return 9;
+
+	case TCK_800MHZ:
+	case TCK_700MHZ:
+		return 8;
+
+	case TCK_666MHZ:
+		return 7;
+
+	case TCK_533MHZ:
+		return 6;
+
+	default:
+		return 5;
+	}
+}
+
 /* Get REFI based on frequency index, tREFI = 7.8usec */
 static u32 get_REFI(u32 FRQ, u8 base_freq)
 {