build: define CPU only when arch/${ARCH}/cpu/${CPU} exists

[karo-tx-uboot.git] / README

diff --git a/README b/README
index d0723701c8c511900ecf9e9380fc00a516abeb6b..0c98545a0d174e6fd0daeed9d11d08de2dd620a6 100644 (file)
--- a/README
+++ b/README
@@ -4156,6 +4156,37 @@ but it can not erase, write this NOR flash by SRIO or PCIE interface.
          You will probably want to define these to avoid a really noisy system
          when storing the env in UBI.
 
+- CONFIG_ENV_IS_IN_FAT:
+       Define this if you want to use the FAT file system for the environment.
+
+       - FAT_ENV_INTERFACE:
+
+         Define this to a string that is the name of the block device.
+
+       - FAT_ENV_DEV_AND_PART:
+
+         Define this to a string to specify the partition of the device. It can
+         be as following:
+
+           "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
+               - "D:P": device D partition P. Error occurs if device D has no
+                        partition table.
+               - "D:0": device D.
+               - "D" or "D:": device D partition 1 if device D has partition
+                              table, or the whole device D if has no partition
+                              table.
+               - "D:auto": first partition in device D with bootable flag set.
+                           If none, first valid paratition in device D. If no
+                           partition table then means device D.
+
+       - FAT_ENV_FILE:
+
+         It's a string of the FAT file name. This file use to store the
+         envrionment.
+
+       - CONFIG_FAT_WRITE:
+         This should be defined. Otherwise it cannot save the envrionment file.
+
 - CONFIG_ENV_IS_IN_MMC:
 
        Define this if you have an MMC device which you want to use for the
@@ -4676,6 +4707,33 @@ within that device.
        window->master inbound window->master LAW->the ucode address in
        master's memory space.
 
+Freescale Layerscape Management Complex Firmware Support:
+---------------------------------------------------------
+The Freescale Layerscape Management Complex (MC) supports the loading of
+"firmware".
+This firmware often needs to be loaded during U-Boot booting, so macros
+are used to identify the storage device (NOR flash, SPI, etc) and the address
+within that device.
+
+- CONFIG_FSL_MC_ENET
+       Enable the MC driver for Layerscape SoCs.
+
+- CONFIG_SYS_LS_MC_FW_ADDR
+       The address in the storage device where the firmware is located.  The
+       meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
+       is also specified.
+
+- CONFIG_SYS_LS_MC_FW_LENGTH
+       The maximum possible size of the firmware.  The firmware binary format
+       has a field that specifies the actual size of the firmware, but it
+       might not be possible to read any part of the firmware unless some
+       local storage is allocated to hold the entire firmware first.
+
+- CONFIG_SYS_LS_MC_FW_IN_NOR
+       Specifies that MC firmware is located in NOR flash, mapped as
+       normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
+       virtual address in NOR flash.
+
 Building the Software:
 ======================
 
@@ -5331,6 +5389,11 @@ Information structure as we define in include/asm-<arch>/u-boot.h,
 and make sure that your definition of IMAP_ADDR uses the same value
 as your U-Boot configuration in CONFIG_SYS_IMMR.
 
+Note that U-Boot now has a driver model, a unified model for drivers.
+If you are adding a new driver, plumb it into driver model. If there
+is no uclass available, you are encouraged to create one. See
+doc/driver-model.
+
 
 Configuring the Linux kernel:
 -----------------------------