[PATCH V2] mtd/ifc: Fix location of eccstat registers for IFC V1.0

[mark.marshall at omicronenergy.com]

From: Mark Marshall <mark.marshall at omicronenergy.com>

The commit 7a654172161c ("mtd/ifc: Add support for IFC controller
version 2.0") added support for version 2.0 of the IFC controller.
The version 2.0 controller has the ECC status registers at a different
location to the previous versions.

Correct the fsl_ifc_nand structure so that the ECC status can be read
from the correct location for both version 1.0 and 2.0 of the controller.

Cc: stable at vger.kernel.org
Fixes: 7a654172161c ("mtd/ifc: Add support for IFC controller version 2.0")
Signed-off-by: Mark Marshall <mark.marshall at omicronenergy.com>
---

Changes since v1:

- simplified the reading of the registers.

 drivers/mtd/nand/fsl_ifc_nand.c | 8 +++++++-
 include/linux/fsl_ifc.h         | 8 ++++++--
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/fsl_ifc_nand.c b/drivers/mtd/nand/fsl_ifc_nand.c
index 0a177b1..d1570f5 100644
--- a/drivers/mtd/nand/fsl_ifc_nand.c
+++ b/drivers/mtd/nand/fsl_ifc_nand.c
@@ -258,9 +258,15 @@ static void fsl_ifc_run_command(struct mtd_info *mtd)
 		int bufnum = nctrl->page & priv->bufnum_mask;
 		int sector = bufnum * chip->ecc.steps;
 		int sector_end = sector + chip->ecc.steps - 1;
+		__be32 *eccstat_regs;
+
+		if (ctrl->version >= FSL_IFC_VERSION_2_0_0)
+			eccstat_regs = ifc->ifc_nand.v2_nand_eccstat;
+		else
+			eccstat_regs = ifc->ifc_nand.v1_nand_eccstat;
 
 		for (i = sector / 4; i <= sector_end / 4; i++)
-			eccstat[i] = ifc_in32(&ifc->ifc_nand.nand_eccstat[i]);
+			eccstat[i] = ifc_in32(&eccstat_regs[i]);
 
 		for (i = sector; i <= sector_end; i++) {
 			errors = check_read_ecc(mtd, ctrl, eccstat, i);
diff --git a/include/linux/fsl_ifc.h b/include/linux/fsl_ifc.h
index 3f9778c..c332f0a 100644
--- a/include/linux/fsl_ifc.h
+++ b/include/linux/fsl_ifc.h
@@ -733,8 +733,12 @@ struct fsl_ifc_nand {
 	__be32 nand_erattr1;
 	u32 res19[0x10];
 	__be32 nand_fsr;
-	u32 res20[0x3];
-	__be32 nand_eccstat[6];
+	u32 res20;
+	/* The V1 nand_eccstat is actually 4 words that overlaps the
+	 * V2 nand_eccstat.
+	 */
+	__be32 v1_nand_eccstat[2];
+	__be32 v2_nand_eccstat[6];
 	u32 res21[0x1c];
 	__be32 nanndcr;
 	u32 res22[0x2];
-- 
2.7.4