MX53: DDR: Fix ZQHWCTRL field TZQ_CS

[u-boot] / doc / README.nand

diff --git a/doc/README.nand b/doc/README.nand
index 751b6938435b7ebf6287b0fd0e1c92cc2916ef88..04a87c99184be6e229cfbe3d5a8d035adfd6894d 100644 (file)
--- a/doc/README.nand
+++ b/doc/README.nand
@@ -94,6 +94,15 @@ Commands:
       of data for one 512-byte page or 2 256-byte pages. There is no check
       for bad blocks.
 
+   nand read.raw addr ofs|partition
+      Read page from `ofs' in NAND flash to `addr'. This reads the raw page,
+      so ECC is avoided and the OOB area is read as well.
+
+   nand write.raw addr ofs|partition
+      Write page from `addr' to `ofs' in NAND flash. This writes the raw page,
+      so ECC is avoided and the OOB area is written as well, making the whole
+      page written as-is.
+
 Configuration Options:
 
    CONFIG_CMD_NAND
@@ -111,6 +120,68 @@ Configuration Options:
    CONFIG_SYS_NAND_MAX_CHIPS
       The maximum number of NAND chips per device to be supported.
 
+   CONFIG_SYS_NAND_SELF_INIT
+      Traditionally, glue code in drivers/mtd/nand/nand.c has driven
+      the initialization process -- it provides the mtd and nand
+      structs, calls a board init function for a specific device,
+      calls nand_scan(), and registers with mtd.
+
+      This arrangement does not provide drivers with the flexibility to
+      run code between nand_scan_ident() and nand_scan_tail(), or other
+      deviations from the "normal" flow.
+
+      If a board defines CONFIG_SYS_NAND_SELF_INIT, drivers/mtd/nand/nand.c
+      will make one call to board_nand_init(), with no arguments.  That
+      function is responsible for calling a driver init function for
+      each NAND device on the board, that performs all initialization
+      tasks except setting mtd->name, and registering with the rest of
+      U-Boot.  Those last tasks are accomplished by calling  nand_register()
+      on the new mtd device.
+
+      Example of new init to be added to the end of an existing driver
+      init:
+
+       /*
+        * devnum is the device number to be used in nand commands
+        * and in mtd->name.  Must be less than
+        * CONFIG_SYS_NAND_MAX_DEVICE.
+        */
+       mtd = &nand_info[devnum];
+
+       /* chip is struct nand_chip, and is now provided by the driver. */
+       mtd->priv = &chip;
+
+       /*
+        * Fill in appropriate values if this driver uses these fields,
+        * or uses the standard read_byte/write_buf/etc. functions from
+        * nand_base.c that use these fields.
+        */
+       chip.IO_ADDR_R = ...;
+       chip.IO_ADDR_W = ...;
+
+       if (nand_scan_ident(mtd, CONFIG_SYS_MAX_NAND_CHIPS, NULL))
+               error out
+
+       /*
+        * Insert here any code you wish to run after the chip has been
+        * identified, but before any other I/O is done.
+        */
+
+       if (nand_scan_tail(mtd))
+               error out
+
+       if (nand_register(devnum))
+               error out
+
+      In addition to providing more flexibility to the driver, it reduces
+      the difference between a U-Boot driver and its Linux counterpart.
+      nand_init() is now reduced to calling board_nand_init() once, and
+      printing a size summary.  This should also make it easier to
+      transition to delayed NAND initialization.
+
+      Please convert your driver even if you don't need the extra
+      flexibility, so that one day we can eliminate the old mechanism.
+
 NOTE:
 =====