Jacob Garber has uploaded this change for review.

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sb/amd/{cimx,}/sb{700,800,900}: Prevent uninitialized reads

"There are two hard things in computer science: cache invalidation,
naming things, and off-by-one errors."

var_num records the number of initialized entries in the reg_var array.
However, this means the index of the last initialized element is one
less than the value of var_num, so we need to take that into account
when indexing into the array. This has already been fixed in several
other places (eg. sb/amd/pi/hudson/lpc.c), so let's also do so here.

Change-Id: Ibefabaca42866a3f2b22eff979c73badf86ac317
Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Found-by: scan-build 8.0.0
---
M src/southbridge/amd/cimx/sb800/lpc.c
M src/southbridge/amd/cimx/sb900/lpc.c
M src/southbridge/amd/sb700/lpc.c
M src/southbridge/amd/sb800/lpc.c
4 files changed, 12 insertions(+), 12 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/90/33790/1

diff --git a/src/southbridge/amd/cimx/sb800/lpc.c b/src/southbridge/amd/cimx/sb800/lpc.c
index a88d6d3..483d185 100644
--- a/src/southbridge/amd/cimx/sb800/lpc.c
+++ b/src/southbridge/amd/cimx/sb800/lpc.c
@@ -170,11 +170,11 @@
 	pci_write_config32(dev, 0x48, reg_x);
 	/* Set WideIO for as many IOs found (fall through is on purpose) */
 	switch (var_num) {
-	case 2:
+	case 3:
 		pci_write_config16(dev, 0x90, reg_var[2]);
-	case 1:
+	case 2:
 		pci_write_config16(dev, 0x66, reg_var[1]);
-	case 0:
+	case 1:
 		//pci_write_config16(dev, 0x64, reg_var[0]); //cause filo can not find sata
 		break;
 	}
diff --git a/src/southbridge/amd/cimx/sb900/lpc.c b/src/southbridge/amd/cimx/sb900/lpc.c
index b04ecfa..8fcb947 100644
--- a/src/southbridge/amd/cimx/sb900/lpc.c
+++ b/src/southbridge/amd/cimx/sb900/lpc.c
@@ -168,11 +168,11 @@
 	pci_write_config32(dev, 0x48, reg_x);
 	/* Set WideIO for as many IOs found (fall through is on purpose) */
 	switch (var_num) {
-	case 2:
+	case 3:
 		pci_write_config16(dev, 0x90, reg_var[2]);
-	case 1:
+	case 2:
 		pci_write_config16(dev, 0x66, reg_var[1]);
-	case 0:
+	case 1:
 		//pci_write_config16(dev, 0x64, reg_var[0]); //cause filo can not find sata
 		break;
 	}
diff --git a/src/southbridge/amd/sb700/lpc.c b/src/southbridge/amd/sb700/lpc.c
index 6f3be03..b7f0dc3 100644
--- a/src/southbridge/amd/sb700/lpc.c
+++ b/src/southbridge/amd/sb700/lpc.c
@@ -228,11 +228,11 @@
 	pci_write_config32(dev, 0x48, reg_x);
 	/* Set WideIO for as many IOs found (fall through is on purpose) */
 	switch (var_num) {
-	case 2:
+	case 3:
 		pci_write_config16(dev, 0x90, reg_var[2]);
-	case 1:
+	case 2:
 		pci_write_config16(dev, 0x66, reg_var[1]);
-	case 0:
+	case 1:
 		pci_write_config16(dev, 0x64, reg_var[0]);
 		break;
 	}
diff --git a/src/southbridge/amd/sb800/lpc.c b/src/southbridge/amd/sb800/lpc.c
index 649add5..74b6374 100644
--- a/src/southbridge/amd/sb800/lpc.c
+++ b/src/southbridge/amd/sb800/lpc.c
@@ -220,11 +220,11 @@
 	pci_write_config32(dev, 0x48, reg_x);
 	/* Set WideIO for as many IOs found (fall through is on purpose) */
 	switch (var_num) {
-	case 2:
+	case 3:
 		pci_write_config16(dev, 0x90, reg_var[2]);
-	case 1:
+	case 2:
 		pci_write_config16(dev, 0x66, reg_var[1]);
-	case 0:
+	case 1:
 		pci_write_config16(dev, 0x64, reg_var[0]);
 		break;
 	}

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