mtd: rawnand: denali: remove hard-coded DENALI_DEFAULT_OOB_SKIP_BYTES

As commit 0d55c668b218 (mtd: rawnand: denali: set SPARE_AREA_SKIP_BYTES
register to 8 if unset") says, there were three solutions discussed:

  [1] Add a DT property to specify the skipped bytes in OOB
  [2] Associate the preferred value with compatible
  [3] Hard-code the default value in the driver

At that time, [3] was chosen because I did not have enough information
about the other platforms than UniPhier.

That commit also says "The preferred value may vary by platform. If so,
please trade up to a different solution." My intention was to replace
[3] with [2], not keep both [2] and [3].

Now that we have switched to [2] for SOCFPGA's SPARE_AREA_SKIP_BYTES=2,
[3] should be removed. This should be OK because denali_pci.c just
gets back to the original behavior.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c
index b6c463d..fafd0a0 100644 (file)
--- a/drivers/mtd/nand/raw/denali.c
+++ b/drivers/mtd/nand/raw/denali.c
@@ -21,7 +21,6 @@
 #include "denali.h"
 
 #define DENALI_NAND_NAME    "denali-nand"
-#define DENALI_DEFAULT_OOB_SKIP_BYTES  8
 
 /* for Indexed Addressing */
 #define DENALI_INDEXED_CTRL    0x00
@@ -1302,22 +1301,16 @@ int denali_init(struct denali_controller *denali)
 
        /*
         * Set how many bytes should be skipped before writing data in OOB.
-        * If a non-zero value has already been configured, update it in HW.
-        * If a non-zero value has already been set (by firmware or something),
-        * just use it. Otherwise, set the driver's default.
+        * If a platform requests a non-zero value, set it to the register.
+        * Otherwise, read the value out, expecting it has already been set up
+        * by firmware.
         */
-       if (denali->oob_skip_bytes) {
+       if (denali->oob_skip_bytes)
                iowrite32(denali->oob_skip_bytes,
                          denali->reg + SPARE_AREA_SKIP_BYTES);
-       } else {
-               denali->oob_skip_bytes =
-                       ioread32(denali->reg + SPARE_AREA_SKIP_BYTES);
-               if (!denali->oob_skip_bytes) {
-                       denali->oob_skip_bytes = DENALI_DEFAULT_OOB_SKIP_BYTES;
-                       iowrite32(denali->oob_skip_bytes,
-                                 denali->reg + SPARE_AREA_SKIP_BYTES);
-               }
-       }
+       else
+               denali->oob_skip_bytes = ioread32(denali->reg +
+                                                 SPARE_AREA_SKIP_BYTES);
 
        iowrite32(0, denali->reg + TRANSFER_SPARE_REG);
        iowrite32(GENMASK(denali->nbanks - 1, 0), denali->reg + RB_PIN_ENABLED);