[MTD] OneNAND: Enhanced support for DDP (Dual Densitiy Packages)

Add density mask for better support of DDP chips.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 19 insertions, 21 deletions

diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index a002d4025b29..99de2f055eb1 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -84,25 +84,23 @@ static void onenand_writew(unsigned short value, void __iomem *addr)
 
 /**
  * onenand_block_address - [DEFAULT] Get block address
- * @param device        the device id
+ * @param this          onenand chip data structure
  * @param block         the block
  * @return              translated block address if DDP, otherwise same
  *
  * Setup Start Address 1 Register (F100h)
  */
-static int onenand_block_address(int device, int block)
+static int onenand_block_address(struct onenand_chip *this, int block)
 {
-        if (device & ONENAND_DEVICE_IS_DDP) {
+        if (this->device_id & ONENAND_DEVICE_IS_DDP) {
                 /* Device Flash Core select, NAND Flash Block Address */
-                int dfs = 0, density, mask;
+                int dfs = 0;
 
-                density = device >> ONENAND_DEVICE_DENSITY_SHIFT;
-                mask = (1 << (density + 6));
-
-                if (block & mask)
+                if (block & this->density_mask)
                         dfs = 1;
 
-                return (dfs << ONENAND_DDP_SHIFT) | (block & (mask - 1));
+                return (dfs << ONENAND_DDP_SHIFT) |
+                        (block & (this->density_mask - 1));
         }
 
         return block;
@@ -110,22 +108,19 @@ static int onenand_block_address(int device, int block)
 
 /**
  * onenand_bufferram_address - [DEFAULT] Get bufferram address
- * @param device        the device id
+ * @param this          onenand chip data structure
  * @param block         the block
  * @return              set DBS value if DDP, otherwise 0
  *
  * Setup Start Address 2 Register (F101h) for DDP
  */
-static int onenand_bufferram_address(int device, int block)
+static int onenand_bufferram_address(struct onenand_chip *this, int block)
 {
-        if (device & ONENAND_DEVICE_IS_DDP) {
+        if (this->device_id & ONENAND_DEVICE_IS_DDP) {
                 /* Device BufferRAM Select */
-                int dbs = 0, density, mask;
-
-                density = device >> ONENAND_DEVICE_DENSITY_SHIFT;
-                mask = (1 << (density + 6));
+                int dbs = 0;
 
-                if (block & mask)
+                if (block & this->density_mask)
                         dbs = 1;
 
                 return (dbs << ONENAND_DDP_SHIFT);
@@ -223,7 +218,7 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
         /* NOTE: The setting order of the registers is very important! */
         if (cmd == ONENAND_CMD_BUFFERRAM) {
                 /* Select DataRAM for DDP */
-                value = onenand_bufferram_address(this->device_id, block);
+                value = onenand_bufferram_address(this, block);
                 this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
 
                 /* Switch to the next data buffer */
@@ -234,7 +229,7 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
 
         if (block != -1) {
                 /* Write 'DFS, FBA' of Flash */
-                value = onenand_block_address(this->device_id, block);
+                value = onenand_block_address(this, block);
                 this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
         }
 
@@ -263,7 +258,7 @@ static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t le
                         
                 if (readcmd) {
                         /* Select DataRAM for DDP */
-                        value = onenand_bufferram_address(this->device_id, block);
+                        value = onenand_bufferram_address(this, block);
                         this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
                 }
         }
@@ -1313,7 +1308,7 @@ static int onenand_unlock(struct mtd_info *mtd, loff_t ofs, size_t len)
                         continue;
 
                 /* Set block address for read block status */
-                value = onenand_block_address(this->device_id, block);
+                value = onenand_block_address(this, block);
                 this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
 
                 /* Check lock status */
@@ -1415,6 +1410,8 @@ static int onenand_probe(struct mtd_info *mtd)
 
         density = dev_id >> ONENAND_DEVICE_DENSITY_SHIFT;
         this->chipsize = (16 << density) << 20;
+        /* Set density mask. it is used for DDP */
+        this->density_mask = (1 << (density + 6));
 
         /* OneNAND page size & block size */
         /* The data buffer size is equal to page size */
diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h
index afaa6342aa7f..d27fd12d096d 100644
--- a/include/linux/mtd/onenand.h
+++ b/include/linux/mtd/onenand.h
@@ -84,6 +84,7 @@ struct onenand_chip {
         void __iomem            *base;
         unsigned int            chipsize;
         unsigned int            device_id;
+        unsigned int            density_mask;
         unsigned int            options;
 
         unsigned int            erase_shift;