nb/intel/i945: Check if interleaved even if rank #4 size is zero

Tested config:
Interleaved (config; status before, after):
 DIMM{0 + 2}: ok, ok
 DIMM{0 + 3}: Nok, ok
 DIMM{1 + 2}: ok, ok
 DIMM{1 + 3}: Nok, ok
 DIMM{1 + 2 + 3}: ok, ok
 DIMM{0 + 2 + 3}: ok, ok
 DIMM{0 + 1 + 2}: ok, ok
 DIMM{0 + 1 + 3}: Nok, ok

Not Interleaved:
 DIMM{0 + 1 + 3}: Nok, Nok
 DIMM{0 + 1 + 2}: ok, ok (with single ranked)
 DIMM{0 + 1 + 2}: Nok, Nok (with only dual ranked)
 DIMM{0 + 2 + 3}: Nok, ok
 DIMM{1 + 2 + 3}: ok, ok

Change-Id: Ibf130a3d4b6f8fa816f7a5f06822a9b8807be3d4
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/31007
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

1 files changed, 5 insertions, 15 deletions

diff --git a/src/northbridge/intel/i945/raminit.c b/src/northbridge/intel/i945/raminit.c
index d41b913ab1..1e8cf65581 100644
--- a/src/northbridge/intel/i945/raminit.c
+++ b/src/northbridge/intel/i945/raminit.c
@@ -2546,29 +2546,19 @@ static void sdram_jedec_enable(struct sys_info *sysinfo)
 	u32 bankaddr = 0, tmpaddr, mrsaddr = 0;
 
 	for (i = 0, nonzero = -1; i < 8; i++) {
-		if (sysinfo->banksize[i]  == 0)
+		if (sysinfo->banksize[i] == 0)
 			continue;
 
 		printk(BIOS_DEBUG, "jedec enable sequence: bank %d\n", i);
-		switch (i) {
-		case 0:
-			/* Start at address 0 */
-			bankaddr = 0;
-			break;
-		case 4:
-			if (sysinfo->interleaved) {
+
+		if (nonzero != -1) {
+			if (sysinfo->interleaved && nonzero < 4 && i >= 4) {
 				bankaddr = 0x40;
-				break;
-			}
-		default:
-			if (nonzero != -1) {
+			} else {
 				printk(BIOS_DEBUG, "bankaddr from bank size of rank %d\n", nonzero);
 				bankaddr += sysinfo->banksize[nonzero] <<
 					(sysinfo->interleaved ? 26 : 25);
-				break;
 			}
-			/* No populated bank hit before. Start at address 0 */
-			bankaddr = 0;
 		}
 
 		/* We have a bank with a non-zero size.. Remember it