[MTD] [NAND] Blackfin on-chip NAND Flash Controller driver

This is the driver for latest Blackfin on-chip nand flash controller

 - use nand_chip and mtd_info common nand driver interface
 - provide both PIO and dma operation
 - compiled with ezkit bf548 configuration
 - use hardware 1-bit ECC
 - tested with YAFFS2 and can mount YAFFS2 filesystem as rootfs

ChangeLog from try#1
 - use hweight32() instead of count_bits()
 - replace bf54x with bf5xx and BF54X with BF5XX
 - compare against plat->page_size in 2 cases when enable hardware ECC

ChangeLog from try#2
 - passed nand_test suites
 - use cpu_relax() instead of busy wait loop
 - some coding style issue pointed out by Andrew

Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

drivers/mtd/nand/Kconfig

@@ -91,6 +91,25 @@ config MTD_NAND_AU1550
 	  This enables the driver for the NAND flash controller on the
 	  AMD/Alchemy 1550 SOC.
 
+config MTD_NAND_BF5XX
+	tristate "Blackfin on-chip NAND Flash Controller driver"
+	depends on BF54x && MTD_NAND
+	help
+	  This enables the Blackfin on-chip NAND flash controller
+
+	  No board specific support is done by this driver, each board
+	  must advertise a platform_device for the driver to attach.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called bf5xx-nand.
+
+config MTD_NAND_BF5XX_HWECC
+	bool "BF5XX NAND Hardware ECC"
+	depends on MTD_NAND_BF5XX
+	help
+	  Enable the use of the BF5XX's internal ECC generator when
+	  using NAND.
+
 config MTD_NAND_RTC_FROM4
 	tristate "Renesas Flash ROM 4-slot interface board (FROM_BOARD4)"
 	depends on SH_SOLUTION_ENGINE

drivers/mtd/nand/Makefile

@@ -13,6 +13,7 @@ obj-$(CONFIG_MTD_NAND_TOTO)		+= toto.o
 obj-$(CONFIG_MTD_NAND_AUTCPU12)		+= autcpu12.o
 obj-$(CONFIG_MTD_NAND_EDB7312)		+= edb7312.o
 obj-$(CONFIG_MTD_NAND_AU1550)		+= au1550nd.o
+obj-$(CONFIG_MTD_NAND_BF5XX)		+= bf5xx_nand.o
 obj-$(CONFIG_MTD_NAND_PPCHAMELEONEVB)	+= ppchameleonevb.o
 obj-$(CONFIG_MTD_NAND_S3C2410)		+= s3c2410.o
 obj-$(CONFIG_MTD_NAND_DISKONCHIP)	+= diskonchip.o