Merge branch 'master' of git://git.denx.de/u-boot-arm

[kernel/u-boot.git] / doc / README.nand

diff --git a/doc/README.nand b/doc/README.nand
index 913e9b5..b91f198 100644 (file)
--- a/doc/README.nand
+++ b/doc/README.nand
@@ -104,6 +104,16 @@ Configuration Options:
    CONFIG_SYS_MAX_NAND_DEVICE
       The maximum number of NAND devices you want to support.
 
    CONFIG_SYS_MAX_NAND_DEVICE
       The maximum number of NAND devices you want to support.
 

+   CONFIG_SYS_NAND_MAX_ECCPOS
+      If specified, overrides the maximum number of ECC bytes
+      supported.  Useful for reducing image size, especially with SPL.
+      This must be at least 48 if nand_base.c is used.
+
+   CONFIG_SYS_NAND_MAX_OOBFREE
+      If specified, overrides the maximum number of free OOB regions
+      supported.  Useful for reducing image size, especially with SPL.
+      This must be at least 2 if nand_base.c is used.
+

    CONFIG_SYS_NAND_MAX_CHIPS
       The maximum number of NAND chips per device to be supported.
 
    CONFIG_SYS_NAND_MAX_CHIPS
       The maximum number of NAND chips per device to be supported.
 


@@ -169,6 +179,59 @@ Configuration Options:
       Please convert your driver even if you don't need the extra
       flexibility, so that one day we can eliminate the old mechanism.
 
       Please convert your driver even if you don't need the extra
       flexibility, so that one day we can eliminate the old mechanism.
 

+
+   CONFIG_SYS_NAND_ONFI_DETECTION
+       Enables detection of ONFI compliant devices during probe.
+       And fetching device parameters flashed on device, by parsing
+       ONFI parameter page.
+
+   CONFIG_BCH
+       Enables software based BCH ECC algorithm present in lib/bch.c
+       This is used by SoC platforms which do not have built-in ELM
+       hardware engine required for BCH ECC correction.
+
+
+Platform specific options
+=========================
+   CONFIG_NAND_OMAP_GPMC
+       Enables omap_gpmc.c driver for OMAPx and AMxxxx platforms.
+       GPMC controller is used for parallel NAND flash devices, and can
+       do ECC calculation (not ECC error detection) for HAM1, BCH4, BCH8
+       and BCH16 ECC algorithms.
+
+   CONFIG_NAND_OMAP_ELM
+       Enables omap_elm.c driver for OMAPx and AMxxxx platforms.
+       ELM controller is used for ECC error detection (not ECC calculation)
+       of BCH4, BCH8 and BCH16 ECC algorithms.
+       Some legacy platforms like OMAP3xx do not have in-built ELM h/w engine,
+       thus such SoC platforms need to depend on software library for ECC error
+       detection. However ECC calculation on such plaforms would still be
+       done by GPMC controller.
+
+   CONFIG_NAND_OMAP_ECCSCHEME
+       On OMAP platforms, this CONFIG specifies NAND ECC scheme.
+       It can take following values:
+       OMAP_ECC_HAM1_CODE_SW
+               1-bit Hamming code using software lib.
+               (for legacy devices only)
+       OMAP_ECC_HAM1_CODE_HW
+               1-bit Hamming code using GPMC hardware.
+               (for legacy devices only)
+       OMAP_ECC_BCH4_CODE_HW_DETECTION_SW
+               4-bit BCH code (unsupported)
+       OMAP_ECC_BCH4_CODE_HW
+               4-bit BCH code (unsupported)
+       OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
+               8-bit BCH code with
+               - ecc calculation using GPMC hardware engine,
+               - error detection using software library.
+               - requires CONFIG_BCH to enable software BCH library
+               (For legacy device which do not have ELM h/w engine)
+       OMAP_ECC_BCH8_CODE_HW
+               8-bit BCH code with
+               - ecc calculation using GPMC hardware engine,
+               - error detection using ELM hardware engine.
+

 NOTE:
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 NOTE:
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