sunxi: increase SYS_MONITOR_LEN

[karo-tx-uboot.git] / doc / README.nand

diff --git a/doc/README.nand b/doc/README.nand
index 70cf768d237056460e0bd1261a3bb0c980c4dc30..0ff56331d5f92ec1ba0dbea186e40d36b4a06cb2 100644 (file)
--- a/doc/README.nand
+++ b/doc/README.nand
@@ -89,18 +89,16 @@ Commands:
 
 Configuration Options:
 
+   CONFIG_SYS_NAND_U_BOOT_OFFS
+       NAND Offset from where SPL will read u-boot image. This is the starting
+       address of u-boot MTD partition in NAND.
+
    CONFIG_CMD_NAND
       Enables NAND support and commmands.
 
    CONFIG_CMD_NAND_TORTURE
       Enables the torture command (see description of this command below).
 
-   CONFIG_MTD_NAND_ECC_JFFS2
-      Define this if you want the Error Correction Code information in
-      the out-of-band data to be formatted to match the JFFS2 file system.
-      CONFIG_MTD_NAND_ECC_YAFFS would be another useful choice for
-      someone to implement.
-
    CONFIG_SYS_MAX_NAND_DEVICE
       The maximum number of NAND devices you want to support.
 
@@ -190,24 +188,6 @@ Configuration Options:
        This is used by SoC platforms which do not have built-in ELM
        hardware engine required for BCH ECC correction.
 
-   CONFIG_SYS_NAND_BUSWIDTH_16BIT
-       Indicates that NAND device has 16-bit wide data-bus. In absence of this
-       config, bus-width of NAND device is assumed to be either 8-bit and later
-       determined by reading ONFI params.
-       Above config is useful when NAND device's bus-width information cannot
-       be determined from on-chip ONFI params, like in following scenarios:
-       - SPL boot does not support reading of ONFI parameters. This is done to
-         keep SPL code foot-print small.
-       - In current U-Boot flow using nand_init(), driver initialization
-         happens in board_nand_init() which is called before any device probe
-         (nand_scan_ident + nand_scan_tail), thus device's ONFI parameters are
-         not available while configuring controller. So a static CONFIG_NAND_xx
-         is needed to know the device's bus-width in advance.
-       Some drivers using above config are:
-       drivers/mtd/nand/mxc_nand.c
-       drivers/mtd/nand/ndfc.c
-       drivers/mtd/nand/omap_gpmc.c
-
 
 Platform specific options
 =========================
@@ -226,6 +206,14 @@ Platform specific options
        detection. However ECC calculation on such plaforms would still be
        done by GPMC controller.
 
+   CONFIG_SPL_NAND_AM33XX_BCH
+       Enables SPL-NAND driver (am335x_spl_bch.c) which supports ELM based
+        hardware ECC correction. This is useful for platforms which have ELM
+       hardware engine and use NAND boot mode.
+       Some legacy platforms like OMAP3xx do not have in-built ELM h/w engine,
+       so those platforms should use CONFIG_SPL_NAND_SIMPLE for enabling
+        SPL-NAND driver with software ECC correction support.
+
    CONFIG_NAND_OMAP_ECCSCHEME
        On OMAP platforms, this CONFIG specifies NAND ECC scheme.
        It can take following values:
@@ -292,15 +280,14 @@ Platform specific options
                Thus BCH16 can be supported on 4K page NAND.
 
 
+    CONFIG_NAND_OMAP_GPMC_PREFETCH
+       On OMAP platforms that use the GPMC controller
+       (CONFIG_NAND_OMAP_GPMC_PREFETCH), this options enables the code that
+       uses the prefetch mode to speed up read operations.
+
 NOTE:
 =====
 
-The current NAND implementation is based on what is in recent
-Linux kernels.  The old legacy implementation has been removed.
-
-If you have board code which used CONFIG_NAND_LEGACY, you'll need
-to convert to the current NAND interface for it to continue to work.
-
 The Disk On Chip driver is currently broken and has been for some time.
 There is a driver in drivers/mtd/nand, taken from Linux, that works with
 the current NAND system but has not yet been adapted to the u-boot