drivers/edac: fix e752x reversed csrows

Found a 'reversal' decoding bug in the driver.  This patch fixes that mapping
to correctly display the CSROW entries in their proper order.  Users will be
enable to correctly identifiy the failing DIMM with this fix.

[akpm@linux-foundation.org: unneeded (and undesirable) cast of void*]
Cc: Alan Cox alan@lxorguk.ukuu.org.uk
Signed-off-by: Mark Grondona <mgrondona@llnl.gov>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/edac/e752x_edac.c b/drivers/edac/e752x_edac.c
index a041218..f5168a5 100644
--- a/drivers/edac/e752x_edac.c
+++ b/drivers/edac/e752x_edac.c
@@ -284,9 +284,6 @@
 	/* 0 = channel A, 1 = channel B */
 	channel = !(error_one & 1);
 
-	if (!pvt->map_type)
-		row = 7 - row;
-
 	/* e752x mc reads 34:6 of the DRAM linear address */
 	edac_mc_handle_ce(mci, page, offset_in_page(sec1_add << 4),
 			sec1_syndrome, row, channel, "e752x CE");
@@ -774,6 +771,18 @@
 	return (((ddrcsr >> 12) & 3) == 3);
 }
 
+/* Remap csrow index numbers if map_type is "reverse"
+ */
+static inline int remap_csrow_index(struct mem_ctl_info *mci, int index)
+{
+	struct e752x_pvt *pvt = mci->pvt_info;
+
+	if (!pvt->map_type)
+		return (7 - index);
+
+	return (index);
+}
+
 static void e752x_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
 			u16 ddrcsr)
 {
@@ -804,7 +813,7 @@
 	for (last_cumul_size = index = 0; index < mci->nr_csrows; index++) {
 		/* mem_dev 0=x8, 1=x4 */
 		mem_dev = (dra >> (index * 4 + 2)) & 0x3;
-		csrow = &mci->csrows[index];
+		csrow = &mci->csrows[remap_csrow_index(mci, index)];
 
 		mem_dev = (mem_dev == 2);
 		pci_read_config_byte(pdev, E752X_DRB + index, &value);
@@ -844,7 +853,7 @@
 				struct e752x_pvt *pvt)
 {
 	int index;
-	u8 value, last, row, stat8;
+	u8 value, last, row;
 
 	last = 0;
 	row = 0;
@@ -873,10 +882,6 @@
 			last = value;
 		}
 	}
-
-	/* set the map type.  1 = normal, 0 = reversed */
-	pci_read_config_byte(pdev, E752X_DRM, &stat8);
-	pvt->map_type = ((stat8 & 0x0f) > ((stat8 >> 4) & 0x0f));
 }
 
 /* Return 0 on success or 1 on failure. */
@@ -1003,13 +1008,16 @@
 	mci->edac_check = e752x_check;
 	mci->ctl_page_to_phys = ctl_page_to_phys;
 
-	e752x_init_csrows(mci, pdev, ddrcsr);
-	e752x_init_mem_map_table(pdev, pvt);
-
-	/* set the map type.  1 = normal, 0 = reversed */
+	/* set the map type.  1 = normal, 0 = reversed
+	 * Must be set before e752x_init_csrows in case csrow mapping
+	 * is reversed.
+	 */
 	pci_read_config_byte(pdev, E752X_DRM, &stat8);
 	pvt->map_type = ((stat8 & 0x0f) > ((stat8 >> 4) & 0x0f));
 
+	e752x_init_csrows(mci, pdev, ddrcsr);
+	e752x_init_mem_map_table(pdev, pvt);
+
 	mci->edac_cap |= EDAC_FLAG_NONE;
 	debugf3("%s(): tolm, remapbase, remaplimit\n", __func__);