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-rw-r--r--doc/README.SPL62
-rw-r--r--doc/README.at91-soc22
-rw-r--r--doc/README.fsl-hwconfig25
-rw-r--r--doc/README.m68k4
-rw-r--r--doc/README.mergerbox59
-rw-r--r--doc/README.nand10
-rw-r--r--doc/README.p1023rds101
-rw-r--r--doc/README.p2041rdb123
-rw-r--r--doc/README.qemu_mips2
-rw-r--r--doc/README.scrapyard3
-rw-r--r--doc/README.ublimage141
-rw-r--r--doc/README.update5
12 files changed, 531 insertions, 26 deletions
diff --git a/doc/README.SPL b/doc/README.SPL
new file mode 100644
index 0000000..ce8e19f
--- /dev/null
+++ b/doc/README.SPL
@@ -0,0 +1,62 @@
+Generic SPL framework
+=====================
+
+Overview
+--------
+
+To unify all existing implementations for a secondary program loader (SPL)
+and to allow simply adding of new implementations this generic SPL framework
+has been created. With this framework almost all source files for a board
+can be reused. No code duplication or symlinking is necessary anymore.
+
+
+How it works
+------------
+
+There is a new directory TOPDIR/spl which contains only a Makefile.
+The object files are built separately for SPL and placed in this directory.
+The final binaries which are generated are u-boot-spl, u-boot-spl.bin and
+u-boot-spl.map.
+
+During the SPL build a variable named CONFIG_SPL_BUILD is exported
+in the make environment and also appended to CPPFLAGS with -DCONFIG_SPL_BUILD.
+Source files can therefore be compiled for SPL with different settings.
+ARM-based boards have previously used the option CONFIG_PRELOADER for it.
+
+For example:
+
+ifeq ($(CONFIG_SPL_BUILD),y)
+COBJS-y += board_spl.o
+else
+COBJS-y += board.o
+endif
+
+COBJS-$(CONFIG_SPL_BUILD) += foo.o
+
+#ifdef CONFIG_SPL_BUILD
+ foo();
+#endif
+
+
+The building of SPL images can be with:
+
+#define CONFIG_SPL
+
+Because SPL images normally have a different text base, one have to be
+configured by defining CONFIG_SPL_TEXT_BASE. The linker script have to be
+defined with CONFIG_SPL_LDSCRIPT.
+
+To support generic U-Boot libraries and drivers in the SPL binary one can
+optionally define CONFIG_SPL_XXX_SUPPORT. Currently following options
+are supported:
+
+CONFIG_SPL_LIBCOMMON_SUPPORT (common/libcommon.o)
+CONFIG_SPL_LIBDISK_SUPPORT (disk/libdisk.o)
+CONFIG_SPL_I2C_SUPPORT (drivers/i2c/libi2c.o)
+CONFIG_SPL_GPIO_SUPPORT (drivers/gpio/libgpio.o)
+CONFIG_SPL_MMC_SUPPORT (drivers/mmc/libmmc.o)
+CONFIG_SPL_SERIAL_SUPPORT (drivers/serial/libserial.o)
+CONFIG_SPL_SPI_FLASH_SUPPORT (drivers/mtd/spi/libspi_flash.o)
+CONFIG_SPL_SPI_SUPPORT (drivers/spi/libspi.o)
+CONFIG_SPL_FAT_SUPPORT (fs/fat/libfat.o)
+CONFIG_SPL_LIBGENERIC_SUPPORT (lib/libgeneric.o)
diff --git a/doc/README.at91-soc b/doc/README.at91-soc
index 425fc58..ed6e76a 100644
--- a/doc/README.at91-soc
+++ b/doc/README.at91-soc
@@ -40,25 +40,3 @@ The method for updating
4. Convert arch, driver and boards file to new SoC
5. remove legacy code, if all boards and drives are ready
- Join AT91 and AT91RM9200 SoC
-==============================
-
-Approximately 95 percent of AT91 and AT91RM9200 SoC parts are the same.
-So, we should use the chance, to join both archs togetter.
-
-To do this follow step needed:
-
-1. change Makefile
- @$(MKCONFIG) $(@:_config=) arm arm920t board vendor at91rm9200
- to
- @$(MKCONFIG) $(@:_config=) arm arm920t board vendor at91
-2. remove CONFIG_AT91_LEGACY in board config
-3. convert boards file to new SoC access
-4. convert or change drivers
-
-To support the joining process, a new SoC dir (at91) has been adding to
-arm920t arch directory. This directory contains files like at91rm9200 dir, but
-uses the new c structure Soc access. The advantage of this is, we don't merge
-old Soc access code and new code while the board are not converted.
-Finally we can delete the whole at91rm9200 dir, if all board support the
-new AT91-SoC access.
diff --git a/doc/README.fsl-hwconfig b/doc/README.fsl-hwconfig
index 03fea74..e752505 100644
--- a/doc/README.fsl-hwconfig
+++ b/doc/README.fsl-hwconfig
@@ -19,3 +19,28 @@ audclk
'audclk:12'
Select the 12.288MHz clock
+
+usb
+ Specific to boards have USB controller
+
+ This option specifies the following for a USB controller:
+
+ - which controller mode to use
+ - which USB PHY to use
+
+ This is used by generic USB device-tree fixup function to update
+ modified values of phy type and controller mode.
+
+ Also used for configuring multiple USB controllers such that
+ 'usbN' (where N is 1, 2, etc. refers to controller no.)
+
+ 'phy_type'
+ Select USB phy type: 'utmi' OR 'ulpi'
+
+ 'dr_mode'
+ Select USB controller mode: 'host', 'peripheral' OR 'otg'
+
+ Examples:
+ usb1:dr_mode=host;usb2:dr_mode=peripheral'
+
+ usb1:dr_mode=host,phy_type=utmi;usb2:dr_mode=host'
diff --git a/doc/README.m68k b/doc/README.m68k
index 3766b33..c85febc 100644
--- a/doc/README.m68k
+++ b/doc/README.m68k
@@ -111,7 +111,7 @@ CONFIG_SYS_MBAR -- defines the base address of the MCF5272 configuration registe
CONFIG_SYS_INIT_RAM_ADDR
-- defines the base address of the MCF5272 internal SRAM
CONFIG_SYS_ENET_BD_BASE
- -- defines the base addres of the FEC buffer descriptors
+ -- defines the base address of the FEC buffer descriptors
CONFIG_SYS_SCR -- defines the contents of the System Configuration Register
CONFIG_SYS_SPR -- defines the contents of the System Protection Register
@@ -138,7 +138,7 @@ CONFIG_SYS_INIT_RAM_ADDR
CONFIG_SYS_INT_FLASH_BASE
-- defines the base address of the MCF5282 internal Flash memory
CONFIG_SYS_ENET_BD_BASE
- -- defines the base addres of the FEC buffer descriptors
+ -- defines the base address of the FEC buffer descriptors
CONFIG_SYS_MFD
-- defines the PLL Multiplication Factor Devider
diff --git a/doc/README.mergerbox b/doc/README.mergerbox
new file mode 100644
index 0000000..1994b65
--- /dev/null
+++ b/doc/README.mergerbox
@@ -0,0 +1,59 @@
+Matrix Vision MergerBox
+-----------------------
+
+1. Board Description
+
+ The MergerBox is a 120x160mm single board computing platform
+ for 3D Full-HD digital video processing.
+
+ Power Supply is 10-32VDC.
+
+2 System Components
+
+2.1 CPU
+ Freescale MPC8377 CPU running at 800MHz core and 333MHz csb.
+ 256 MByte DDR-II memory @ 333MHz data rate.
+ 64 MByte Nor Flash on local bus.
+ 1 GByte Nand Flash on FCM.
+ 1 Vitesse VSC8601 RGMII ethernet Phys.
+ 1 USB host controller over ULPI I/F with 4-Port hub.
+ 2 serial ports. Console running on ttyS0 @ 115200 8N1.
+ 1 mPCIe expansion slot (PCIe x1 + USB) used for Wifi/Bt.
+ 2 PCIe x1 busses on local mPCIe and cutom expansion connector.
+ 2 SATA host ports.
+ System configuration (HRCW) is taken from I2C EEPROM.
+
+2.2 Graphics
+ SM107 emebedded video controller driving a 5" 800x480 TFT panel.
+ Connected over 32-Bit/66MHz PCI utilizing 4 MByte embedded memory.
+
+2.3 FPGA
+ Altera Cyclone-IV EP4C115 with several PCI DMA engines.
+ Connects to 7x Gennum 3G-SDI transceivers as video interconnect
+ as well as a HDMI v1.4 compliant output for 3D monitoring.
+ Utilizes two more DDR-II controllers providing 256MB memory.
+
+2.4 I2C
+ Bus1:
+ AD7418 @ 0x50 for voltage/temp. monitoring.
+ SX8650 @ 0x90 touch controller for HMI.
+ EEPROM @ 0xA0 for system setup (HRCW etc.) + vendor specifics.
+ Bus2:
+ mPCIe SMBus
+ SiI9022A @ 0x72/0xC0 HDMI transmitter.
+ TCA6416A @ 0x40 + 0x42 16-Bit I/O expander.
+ LMH1983 @ 0xCA video PLL.
+ DS1338C @ 0xD0 real-time clock with embedded crystal.
+ 9FG104 @ 0xDC 4x 100MHz LVDS SerDes reference clock.
+
+3 Flash layout.
+
+ reset vector is 0x00000100, i.e. low boot.
+
+ 00000000 u-boot binary.
+ 00100000 FPGA raw bit file.
+ 00300000 FIT image holding kernel, dtb and rescue squashfs.
+ 03d00000 u-boot environment.
+ 03e00000 splash image
+
+ mtd partitions are propagated to linux kernel via device tree blob.
diff --git a/doc/README.nand b/doc/README.nand
index 8eedb6c..751b693 100644
--- a/doc/README.nand
+++ b/doc/README.nand
@@ -78,6 +78,16 @@ Commands:
should work well, but loading an image copied from another flash is
going to be trouble if there are any bad blocks.
+ nand write.trimffs addr ofs|partition size
+ Enabled by the CONFIG_CMD_NAND_TRIMFFS macro. This command will write to
+ the NAND flash in a manner identical to the 'nand write' command
+ described above -- with the additional check that all pages at the end
+ of eraseblocks which contain only 0xff data will not be written to the
+ NAND flash. This behaviour is required when flashing UBI images
+ containing UBIFS volumes as per the UBI FAQ[1].
+
+ [1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_flasher_algo
+
nand write.oob addr ofs|partition size
Write `size' bytes from `addr' to the out-of-band data area
corresponding to `ofs' in NAND flash. This is limited to the 16 bytes
diff --git a/doc/README.p1023rds b/doc/README.p1023rds
new file mode 100644
index 0000000..685f5da
--- /dev/null
+++ b/doc/README.p1023rds
@@ -0,0 +1,101 @@
+Overview
+--------
+The P1023 process includes a performance optimized implementation of the
+QorIQ data Path Acceleration Architecture (DPAA). This architecture
+provides the infrastructure to support simplified sharing of networking
+interfaces and accelerators by multiple CPU cores. P1023 is an e500 based
+dual core SOC.
+
+P1023RDS board is a Low End Dual core platform supporting the P1023
+processor of QorIQ series.
+
+Building U-boot
+---------------
+To build the u-boot for P1023RDS:
+Configure to NOR boot:
+ make P1023RDS_config
+Configure to NAND boot:
+ make P1023RDS_NAND_config
+Build:
+ make
+
+Board Switches
+--------------
+Most switches on the board should not be changed. The most frequent
+user-settable switches on the board are used to configure
+the flash banks.
+
+J4: all open
+
+Default NOR flash boot switch setting:
+ Sw3[1:8]: off on on off on on off off
+ Sw4[1:8]: off off off on off off off off
+ Sw6[1:8]: off on off on off on on off
+ Sw7[1:8]: off on off off on off off off
+ Sw8[1:8]: on off off off off off off off
+
+For NAND flash boot,set
+Sw4[1:4]: off on on on
+
+The default native ethernet setting is for RGMII mode.
+To use SGMII mode, set
+SW8[1:2]: OFF OFF
+SW7[6:7]: ON ON
+
+Memory Map
+----------
+0x0000_0000 0x7fff_ffff DDR 2G Cacheable
+0x8000_0000 0xbfff_ffff PCI Express Mem 1G non-cacheable
+0xc000_0000 0xdfff_ffff PCI 512M non-cacheable
+0xe100_0000 0xe3ff_ffff PCI IO range 4M non-cacheable
+
+0xe000_0000 0xe003_ffff BCSR 256K BCSR
+0xee00_0000 0xefff_ffff NOR flash 32M NOR flash
+0xff00_0000 0xff3f_ffff DPAA_QBMAN 4M
+0xff60_0000 0xff7f_ffff CCSR 2M non-cacheable
+0xffa0_0000 0xffaf_ffff NAND FLASH 1M non-cacheable
+0xffd0_0000 0xffd0_3fff L1 for stack 16K Cacheable TLB0
+
+Flashing u-boot Images
+---------------
+To program the image in the boot flash bank:
+NOR flash boot:
+ => tftp 1000000 u-boot.bin
+ => protect off all
+ => erase eff80000 efffffff
+ => cp.b 1000000 eff80000 80000
+
+NAND flash boot:
+ => tftp 1000000 u-boot-nand.bin
+ => nand erase 0 80000
+ => nand write 1000000 0 80000
+
+Firmware ucode location
+---------------------------------
+Microcode(ucode) to FMAN's IRAM is needed to make FMAN Ethernet work.
+u-boot loads ucode FLASH. The location for ucode:
+NOR Flash: 0xfe000000
+NAND Flash: 0x1f00000
+
+Using the Device Tree Source File
+---------------------------------
+To create the DTB (Device Tree Binary) image file,
+use a command similar to this:
+
+ dtc -b 0 -f -I dts -O dtb p1023rds.dts > p1023rds.dtb
+
+Likely, that .dts file will come from here;
+
+ linux-2.6/arch/powerpc/boot/dts/p1023rds.dts
+or
+ make p1023rds.dtb ARCH=powerpc
+in linux-2.6 directory.
+
+Booting Linux
+-------------
+Place a linux uImage in the TFTP disk area.
+
+ tftp 1000000 uImage
+ tftp 2000000 rootfs.ext2.gz.uboot
+ tftp c00000 p1023rds.dtb
+ bootm 1000000 2000000 c00000
diff --git a/doc/README.p2041rdb b/doc/README.p2041rdb
new file mode 100644
index 0000000..292d0d3
--- /dev/null
+++ b/doc/README.p2041rdb
@@ -0,0 +1,123 @@
+Overview
+=========
+The P2041 Processor combines four Power Architecture processor cores
+with high-performance datapath acceleration architecture(DPAA), CoreNet
+fabric infrastructure, as well as network and peripheral bus interfaces
+required for networking, telecom/datacom, wireless infrastructure, and
+military/aerospace applications.
+
+P2041RDB board is a quad core platform supporting the P2041 processor
+of QorIQ DPAA series.
+
+Boot from NOR flash
+===================
+1. Build image
+ make P2041RDB_config
+ make all
+
+2. Program image
+ => tftp 1000000 u-boot.bin
+ => protect off all
+ => erase eff80000 efffffff
+ => cp.b 1000000 eff80000 80000
+
+3. Program RCW
+ => tftp 1000000 rcw.bin
+ => protect off all
+ => erase e8000000 e801ffff
+ => cp.b 1000000 e8000000 50
+
+4. Program FMAN Firmware ucode
+ => tftp 1000000 ucode.bin
+ => protect off all
+ => erase ef000000 ef0fffff
+ => cp.b 1000000 ef000000 2000
+
+5. Change DIP-switch
+ SW1[1-5] = 10110
+ Note: 1 stands for 'on', 0 stands for 'off'
+
+Boot from SDCard
+===================
+1. Build image
+ make P2041RDB_SDCARD_config
+ make all
+
+2. Generate PBL imge
+ Use PE tool to produce a image used to be programed to
+ SDCard which contains RCW and U-Boot image.
+
+3. Program the PBL image to SDCard
+ => tftp 1000000 pbl_sd.bin
+ => mmcinfo
+ => mmc write 1000000 8 441
+
+4. Program FMAN Firmware ucode
+ => tftp 1000000 ucode.bin
+ => mmc write 1000000 46a 10
+
+5. Change DIP-switch
+ SW1[1-5] = 01100
+ Note: 1 stands for 'on', 0 stands for 'off'
+
+Boot from SPI flash
+===================
+1. Build image
+ make P2041RDB_SPIFLASH_config
+ make all
+
+2. Generate PBL imge
+ Use PE tool to produce a image used to be programed to
+ SPI flash which contains RCW and U-Boot image.
+
+3. Program the PBL image to SPI flash
+ => tftp 1000000 pbl_spi.bin
+ => spi probe 0
+ => sf erase 0 100000
+ => sf write 1000000 0 $filesize
+
+4. Program FMAN Firmware ucode
+ => tftp 1000000 ucode.bin
+ => sf erase 110000 10000
+ => sf write 1000000 110000 $filesize
+
+5. Change DIP-switch
+ SW1[1-5] = 10100
+ Note: 1 stands for 'on', 0 stands for 'off'
+
+CPLD command
+============
+The CPLD is used to control the power sequence and some serdes lane
+mux function.
+
+cpld reset - hard reset to default bank
+cpld reset altbank - reset to alternate bank
+cpld lane_mux <lane> <mux_value> - set multiplexed lane pin
+ lane 6: 0 -> slot1 (Default)
+ 1 -> SGMII
+ lane a: 0 -> slot2 (Default)
+ 1 -> AURORA
+ lane c: 0 -> slot2 (Default)
+ 1 -> SATA0
+ lane d: 0 -> slot2 (Default)
+ 1 -> SATA1
+
+Using the Device Tree Source File
+=================================
+To create the DTB (Device Tree Binary) image file, use a command
+similar to this:
+ dtc -O dtb -b 0 -p 1024 p2041rdb.dts > p2041rdb.dtb
+
+Or use the following command:
+ {linux-2.6}/make p2041rdb.dtb ARCH=powerpc
+
+then the dtb file will be generated under the following directory:
+ {linux-2.6}/arch/powerpc/boot/p2041rdb.dtb
+
+Booting Linux
+=============
+Place a linux uImage in the TFTP disk area.
+ tftp 1000000 uImage
+ tftp 2000000 rootfs.ext2.gz.uboot
+ tftp 3000000 p2041rdb.dtb
+ bootm 1000000 2000000 3000000
diff --git a/doc/README.qemu_mips b/doc/README.qemu_mips
index 3985264..e6a3855 100644
--- a/doc/README.qemu_mips
+++ b/doc/README.qemu_mips
@@ -24,7 +24,7 @@ you can downland
#config to build the kernel
qemu_mips_defconfig
-#patch to fix mips interupt init on 2.6.24.y kernel
+#patch to fix mips interrupt init on 2.6.24.y kernel
qemu_mips_kernel.patch
initrd.gz
vmlinux
diff --git a/doc/README.scrapyard b/doc/README.scrapyard
index d7bf9a7..4cb727f 100644
--- a/doc/README.scrapyard
+++ b/doc/README.scrapyard
@@ -11,11 +11,12 @@ easily if here is something they might want to dig for...
Board Arch CPU removed Commit last known maintainer/contact
=============================================================================
+trab arm S3C2400 - 2011-05-01 Gary Jennejohn <garyj@denx.de>
xsengine ARM PXA2xx 4262a7c 2010-10-20
wepep250 ARM PXA2xx 7369478 2010-10-20 Peter Figuli <peposh@etc.sk>
delta ARM PXA2xx 75e2035 2010-10-20
mp2usb ARM AT91RM2900 ee986e2 2011-01-25 Eric BĂ©nard <eric@eukrea.com>
-barco powerpc MPC8245 - 2010-11-23 Marc Leeman <marc.leeman@barco.com>
+barco powerpc MPC8245 afaa27b 2010-11-23 Marc Leeman <marc.leeman@barco.com>
ERIC powerpc 405GP d9ba451 2010-11-21 Swen Anderson <sand@peppercon.de>
VoVPN-GW_100MHz powerpc MPC8260 26fe3d2 2010-10-24 Juergen Selent <j.selent@elmeg.de>
NC650 powerpc MPC852 333d86d 2010-10-19 Wolfgang Denk <wd@denx.de>
diff --git a/doc/README.ublimage b/doc/README.ublimage
new file mode 100644
index 0000000..add24d6
--- /dev/null
+++ b/doc/README.ublimage
@@ -0,0 +1,141 @@
+---------------------------------------------
+UBL image Boot Image generation using mkimage
+---------------------------------------------
+
+This document describes how to set up an U-Boot image that can be directly
+booted by a DaVinci processor via NAND boot mode, using an UBL header,
+but without need for UBL.
+
+For more details see section 11.2 "ARM ROM Boot Modes" of
+http://focus.ti.com/lit/ug/sprufg5a/sprufg5a.pdf
+
+Command syntax:
+--------------
+./tools/mkimage -l <u-boot_file>
+ to list the UBL image file details
+
+./tools/mkimage -T ublimage \
+ -n <board specific configuration file> \
+ -d <u-boot binary> <output image file>
+
+For example, for the davinci dm365evm board:
+./tools/mkimage -n ./board/davinci/dm365evm/ublimage.cfg \
+ -T ublimage \
+ -d u-boot-nand.bin u-boot.ubl
+
+You can generate the image directly when you compile u-boot with:
+
+$ make u-boot.ubl
+
+The output image can be flashed into the NAND.
+
+Please check the DaVinci documentation for further details.
+
+Board specific configuration file specifications:
+-------------------------------------------------
+1. This file must present in the $(BOARDDIR) and the name should be
+ ublimage.cfg (since this is used in Makefile).
+2. This file can have empty lines and lines starting with "#" as first
+ character to put comments.
+3. This file can have configuration command lines as mentioned below,
+ any other information in this file is treated as invalid.
+
+Configuration command line syntax:
+---------------------------------
+1. Each command line must have two strings, first one command or address
+ and second one data string
+2. Following are the valid command strings and associated data strings:-
+ Command string data string
+ -------------- -----------
+ MODE UBL special mode, on of:
+ safe
+ Example:
+ MODE safe
+
+ ENTRY Entry point address for the user
+ bootloader (absolute address) = TEXT_BASE
+ nand_spl loader.
+ Example:
+ ENTRY 0x00000020
+
+ PAGES Number of pages (size of user bootloader
+ in number of pages)
+ Example:
+ PAGES 27
+
+ START_BLOCK Block number where user bootloader is present
+ Example:
+ START_BLOCK 5
+
+ START_PAGE Page number where user bootloader is present
+ (for RBL always 0)
+ Example:
+ START_PAGE 0
+
+------------------------------------------------
+
+Structure of the u-boot.ubl binary:
+
+compile steps:
+
+1) nand_spl code compile, with pad_to = (TEXT_BASE +
+ (CONFIG_SYS_NROF_PAGES_NAND_SPL * pagesize))
+ Example: cam_enc_4xx pad_to = 0x20 + (6 * 0x800) = 0x3020 = 12320
+ -> u-boot-spl-16k.bin
+
+ !! TEXT_BASE = 0x20, as the RBL starts at 0x20
+
+2) compile u-boot.bin ("normal" u-boot)
+ -> u-boot.bin
+
+3) create u-boot-nand.bin = u-boot-spl-16k.bin + u-boot.bin
+
+4) create u-boot.ubl, size = 1 page size NAND
+ create UBL header and paste it before u-boot.bin
+
+This steps are done automagically if you do a "make all"
+
+-> You get an u-boot.ubl binary, which you can flash
+ into your NAND.
+
+Structure of this binary (Example for the cam_enc_4xx board with a NAND
+page size = 0x800):
+
+offset : 0x00000 | 0x800 | 0x3800
+content: UBL | nand_spl | u-boot code
+ Header | code |
+
+The NAND layout looks for example like this:
+
+(Example for the cam_enc_4xx board with a NAND page size = 0x800, block
+size = 0x20000 and CONFIG_SYS_NROF_UBL_HEADER 5):
+
+offset : 0x80000 | 0xa0000 | 0xa3000
+content: UBL | nand_spl | u-boot code
+ Header | code |
+ ^ ^
+ ^ 0xa0000 = CONFIG_SYS_NROF_UBL_HEADER * 0x20000
+ ^
+ 0x80000 = Block 4 * 0x20000
+
+If the cpu starts in NAND boot mode, it checks the UBL descriptor
+starting with block 1 (page 0). When a valid UBL signature is found,
+the corresponding block number (from 1 to 24) is written to the last 32
+bits of ARM internal memory (0x7ffc-0x8000). This feature is provided
+as a basic debug mechanism. If not found, it continues with block 2
+... last possible block is 24
+
+If a valid UBL descriptor is found, the UBL descriptor is read and
+processed. The descriptor gives the information required for loading
+and control transfer to the nand_spl code. The nand_spl code is then
+read and processed.
+
+Once the user-specified start-up conditions are set, the RBL copies the
+nand_spl into ARM internal RAM, starting at address 0x0000: 0020.
+ ^^^^
+
+The nand_spl code itself now does necessary intializations, and at least,
+copies the u-boot code from NAND into RAM, and jumps to it ...
+
+------------------------------------------------
+Author: Heiko Schocher <hs@denx.de>
diff --git a/doc/README.update b/doc/README.update
index 48f03b7..a7f4d9e 100644
--- a/doc/README.update
+++ b/doc/README.update
@@ -51,6 +51,11 @@ the mkimage tool. dtc tool with support for binary includes, e.g. in version
to be prepared. Refer to the doc/uImage.FIT/ directory for more details on FIT
images.
+This mechanism can be also triggered by the commmand "fitupd".
+If an optional, non-zero address is provided as argument, the TFTP transfer
+is skipped and the image at this address is used.
+The fitupd command is enabled by CONFIG_CMD_FITUPD.
+
Example .its files
------------------