amd64_edac: Fix logic to determine channel for F15 M30h processors

Update current channel selection logic to include F15h, M30h memory
controllers.

Refer F15 M30h BKDG D18F2x110[7:6] (DRAM Controller Select Low)
(Link:http://support.amd.com/TechDocs/49125_15h_Models_30h-3Fh_BKDG.pdf)

Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Link: http://lkml.kernel.org/r/1390338216-3873-1-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Borislav Petkov <bp@suse.de>
diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 98e14ee..34380cc 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -1239,9 +1239,17 @@
 	if (num_dcts_intlv == 2) {
 		select = (sys_addr >> 8) & 0x3;
 		channel = select ? 0x3 : 0;
-	} else if (num_dcts_intlv == 4)
-		channel = (sys_addr >> 8) & 0x7;
-
+	} else if (num_dcts_intlv == 4) {
+		u8 intlv_addr = dct_sel_interleave_addr(pvt);
+		switch (intlv_addr) {
+		case 0x4:
+			channel = (sys_addr >> 8) & 0x3;
+			break;
+		case 0x5:
+			channel = (sys_addr >> 9) & 0x3;
+			break;
+		}
+	}
 	return channel;
 }