[MTD] OneNAND: Reduce Double Density Package (DDP) operations
Kyungmin Park [Mon, 15 Jan 2007 08:09:14 +0000 (17:09 +0900)]
- DDP code clean-up
- Reduce block & bufferram operations in DDP

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

drivers/mtd/onenand/onenand_base.c
include/linux/mtd/onenand.h
include/linux/mtd/onenand_regs.h

index ce1cbdc..d88c7f7 100644 (file)
@@ -94,16 +94,9 @@ static void onenand_writew(unsigned short value, void __iomem *addr)
  */
 static int onenand_block_address(struct onenand_chip *this, int block)
 {
-       if (this->device_id & ONENAND_DEVICE_IS_DDP) {
-               /* Device Flash Core select, NAND Flash Block Address */
-               int dfs = 0;
-
-               if (block & this->density_mask)
-                       dfs = 1;
-
-               return (dfs << ONENAND_DDP_SHIFT) |
-                       (block & (this->density_mask - 1));
-       }
+       /* Device Flash Core select, NAND Flash Block Address */
+       if (block & this->density_mask)
+               return ONENAND_DDP_CHIP1 | (block ^ this->density_mask);
 
        return block;
 }
@@ -118,17 +111,11 @@ static int onenand_block_address(struct onenand_chip *this, int block)
  */
 static int onenand_bufferram_address(struct onenand_chip *this, int block)
 {
-       if (this->device_id & ONENAND_DEVICE_IS_DDP) {
-               /* Device BufferRAM Select */
-               int dbs = 0;
-
-               if (block & this->density_mask)
-                       dbs = 1;
+       /* Device BufferRAM Select */
+       if (block & this->density_mask)
+               return ONENAND_DDP_CHIP1;
 
-               return (dbs << ONENAND_DDP_SHIFT);
-       }
-
-       return 0;
+       return ONENAND_DDP_CHIP0;
 }
 
 /**
@@ -757,9 +744,9 @@ static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
                         * Now we issued chip 1 read and pointed chip 1
                         * bufferam so we have to point chip 0 bufferam.
                         */
-                       if (this->device_id & ONENAND_DEVICE_IS_DDP &&
-                                       unlikely(from == (this->chipsize >> 1))) {
-                               this->write_word(0, this->base + ONENAND_REG_START_ADDRESS2);
+                       if (ONENAND_IS_DDP(this) &&
+                           unlikely(from == (this->chipsize >> 1))) {
+                               this->write_word(ONENAND_DDP_CHIP0, this->base + ONENAND_REG_START_ADDRESS2);
                                boundary = 1;
                        } else
                                boundary = 0;
@@ -773,7 +760,7 @@ static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
                        break;
                /* Set up for next read from bufferRAM */
                if (unlikely(boundary))
-                       this->write_word(0x8000, this->base + ONENAND_REG_START_ADDRESS2);
+                       this->write_word(ONENAND_DDP_CHIP1, this->base + ONENAND_REG_START_ADDRESS2);
                ONENAND_SET_NEXT_BUFFERRAM(this);
                buf += thislen;
                thislen = min_t(int, mtd->writesize, len - read);
@@ -1508,7 +1495,7 @@ static int onenand_unlock_all(struct mtd_info *mtd)
                        continue;
 
                /* Workaround for all block unlock in DDP */
-               if (this->device_id & ONENAND_DEVICE_IS_DDP) {
+               if (ONENAND_IS_DDP(this)) {
                        /* 1st block on another chip */
                        loff_t ofs = this->chipsize >> 1;
                        size_t len = mtd->erasesize;
@@ -1963,7 +1950,10 @@ 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));
+       if (ONENAND_IS_DDP(this))
+               this->density_mask = (1 << (density + 6));
+       else
+               this->density_mask = 0;
 
        /* OneNAND page size & block size */
        /* The data buffer size is equal to page size */
index f775a7a..a99b294 100644 (file)
@@ -150,6 +150,9 @@ struct onenand_chip {
 #define ONENAND_SET_SYS_CFG1(v, this)                                  \
        (this->write_word(v, this->base + ONENAND_REG_SYS_CFG1))
 
+#define ONENAND_IS_DDP(this)                                           \
+       (this->device_id & ONENAND_DEVICE_IS_DDP)
+
 /* Check byte access in OneNAND */
 #define ONENAND_CHECK_BYTE_ACCESS(addr)                (addr & 0x1)
 
index e31c8f5..5b46cb5 100644 (file)
 #define ONENAND_VERSION_PROCESS_SHIFT  (8)
 
 /*
- * Start Address 1 F100h (R/W)
+ * Start Address 1 F100h (R/W) & Start Address 2 F101h (R/W)
  */
 #define ONENAND_DDP_SHIFT              (15)
+#define ONENAND_DDP_CHIP0              (0)
+#define ONENAND_DDP_CHIP1              (1 << ONENAND_DDP_SHIFT)
 
 /*
  * Start Address 8 F107h (R/W)