summaryrefslogtreecommitdiff
path: root/doc
diff options
context:
space:
mode:
authorTom Rini <trini@ti.com>2013-03-18 12:31:00 -0400
committerTom Rini <trini@ti.com>2013-03-18 14:37:18 -0400
commit0ce033d2582129243aca10d3072a221386bbba44 (patch)
tree6e50a3f4eed22007549dc740d0fa647a6c8cec5b /doc
parentb5bec88434adb52413f1bc33fa63d7642cb8fd35 (diff)
parentb27673ccbd3d5435319b5c09c3e7061f559f925d (diff)
downloadu-boot-imx-0ce033d2582129243aca10d3072a221386bbba44.zip
u-boot-imx-0ce033d2582129243aca10d3072a221386bbba44.tar.gz
u-boot-imx-0ce033d2582129243aca10d3072a221386bbba44.tar.bz2
Merge branch 'master' of git://git.denx.de/u-boot-arm
Albert's rework of the linker scripts conflicted with Simon's making everyone use __bss_end. We also had a minor conflict over README.scrapyard being added to in mainline and enhanced in u-boot-arm/master with proper formatting. Conflicts: arch/arm/cpu/ixp/u-boot.lds arch/arm/cpu/u-boot.lds arch/arm/lib/Makefile board/actux1/u-boot.lds board/actux2/u-boot.lds board/actux3/u-boot.lds board/dvlhost/u-boot.lds board/freescale/mx31ads/u-boot.lds doc/README.scrapyard include/configs/tegra-common.h Build tested for all of ARM and run-time tested on am335x_evm. Signed-off-by: Tom Rini <trini@ti.com>
Diffstat (limited to 'doc')
-rw-r--r--doc/README.commands18
-rw-r--r--doc/README.displaying-bmps27
-rw-r--r--doc/README.ns9750dev36
-rw-r--r--doc/README.scrapyard163
-rw-r--r--doc/SPL/README.am335x-network92
-rw-r--r--doc/driver-model/UDM-serial.txt2
6 files changed, 210 insertions, 128 deletions
diff --git a/doc/README.commands b/doc/README.commands
index 923418b..9eb3671 100644
--- a/doc/README.commands
+++ b/doc/README.commands
@@ -15,24 +15,22 @@ help: Long description. This is a string
**** Behind the scene ******
-The structure created is named with a special prefix (__u_boot_list_cmd_)
-and placed by the linker in a special section.
+The structure created is named with a special prefix and placed by
+the linker in a special section using the linker lists mechanism
+(see include/linker_lists.h)
This makes it possible for the final link to extract all commands
compiled into any object code and construct a static array so the
-command can be found in an array starting at _u_boot_list_cmd__start.
+command array can be iterated over using the linker lists macros.
-To ensure that the linker does not discard these symbols when linking
-full U-Boot we generate a list of all the commands we have built (based
-on the sections mentioned above) and use that to force the linker to
-first enter the symbol as undefined in the output object so that there
-is then a need for the symbol to be kept (this is the UNDEF_SYM logic in
-the Makefile).
+The linker lists feature ensures that the linker does not discard
+these symbols when linking full U-Boot even though they are not
+referenced in the source code as such.
If a new board is defined do not forget to define the command section
by writing in u-boot.lds ($(TOPDIR)/board/boardname/u-boot.lds) these
3 lines:
.u_boot_list : {
- #include "u-boot.lst";
+ KEEP(*(SORT(.u_boot_list*)));
}
diff --git a/doc/README.displaying-bmps b/doc/README.displaying-bmps
new file mode 100644
index 0000000..3311541
--- /dev/null
+++ b/doc/README.displaying-bmps
@@ -0,0 +1,27 @@
+If you are experiencing hangups/data-aborts when trying to display a BMP image,
+the following might be relevant to your situation...
+
+Some architectures cannot handle unaligned memory accesses, and an attempt to
+perform one will lead to a data abort. On such architectures it is necessary to
+make sure all data is properly aligned, and in many situations simply choosing
+a 32 bit aligned address is enough to ensure proper alignment. This is not
+always the case when dealing with data that has an internal layout such as a
+BMP image:
+
+BMP images have a header that starts with 2 byte-size fields followed by mostly
+32 bit fields. The packed struct that represents this header can be seen below:
+
+typedef struct bmp_header {
+ /* Header */
+ char signature[2];
+ __u32 file_size;
+ __u32 reserved;
+ __u32 data_offset;
+ ... etc
+} __attribute__ ((packed)) bmp_header_t;
+
+When placed in an aligned address such as 0x80a00000, char signature offsets
+the __u32 fields into unaligned addresses (in our example 0x80a00002,
+0x80a00006, and so on...). When these fields are accessed by U-Boot, a 32 bit
+access is generated at a non-32-bit-aligned address, causing a data abort.
+The proper alignment for BMP images is therefore: 32-bit-aligned-address + 2.
diff --git a/doc/README.ns9750dev b/doc/README.ns9750dev
deleted file mode 100644
index 2991440..0000000
--- a/doc/README.ns9750dev
+++ /dev/null
@@ -1,36 +0,0 @@
-U-Boot Port to the NS9750 DevKit from NetSilicon
-
-1 Overview
-2 Board Configuration
-3 Installation
-
-
-1 Overview
-----------
-
-This port supports these NS9750 features.
-
-o one UART
-
-2 Board Configuration
----------------------
-
-Switches:
-SW10: 4
-SW11: 6,7
-SW16: 6,7,8
-SW17-SW20: 1
-SW4: 3, 6
-SW 1: 1
-SW2: 4
-SW3: 3
-SW8: 3 (rotated by 180 degree!!!!)
-
-Serial Console is Port B (bottom right port)
-
-3 Installation
---------------
-
-Have fun,
---
-Markus Pietrek <mpietrek@fsforth.de>
diff --git a/doc/README.scrapyard b/doc/README.scrapyard
index 7d73ea0..189b883 100644
--- a/doc/README.scrapyard
+++ b/doc/README.scrapyard
@@ -9,85 +9,86 @@ maintain a list of such former fellows, so archeologists can check
easily if here is something they might want to dig for...
-Board Arch CPU removed Commit last known maintainer/contact
-=============================================================================
-AMX860 powerpc mpc860 - - Wolfgang Denk <wd@denx.de>
-c2mon powerpc mpc855 - - Wolfgang Denk <wd@denx.de>
-ETX094 powerpc mpc850 - - Wolfgang Denk <wd@denx.de>
-IAD210 powerpc mpc860 - - -
-LANTEC powerpc mpc850 - - Wolfgang Denk <wd@denx.de>
-SCM powerpc mpc8260 - - Wolfgang Grandegger <wg@denx.de>
-SX1 arm arm925t - -
-TQM85xx powerpc MPC85xx d923a5d5 2012-10-04 Stefan Roese <sr@denx.de>
-apollon arm omap24xx 535c74f 2012-09-18 Kyungmin Park <kyungmin.park@samsung.com>
-tb0229 mips mips32 3f3110d 2011-12-12
-rmu powerpc MPC850 fb82fd7 2011-12-07 Wolfgang Denk <wd@denx.de>
-OXC powerpc MPC8240 309a292 2011-12-07
-BAB7xx powerpc MPC740/MPC750 c53043b 2011-12-07 Frank Gottschling <fgottschling@eltec.de>
-xm250 arm pxa c746cdd 2011-25-11
-pleb2 arm pxa b185a1c 2011-25-11
-cradle arm pxa 4e24f8a 2011-25-11 Kyle Harris <kharris@nexus-tech.net>
-cerf250 arm pxa a3f1241 2011-25-11 Prakash Kumar <prakash@embedx.com>
-mpq101 powerpc mpc85xx e877fab 2011-10-23 Alex Dubov <oakad@yahoo.com>
-ixdpg425 arm ixp 0ca8eb7 2011-09-22 Stefan Roese <sr@denx.de>
-ixdp425 arm ixp 0ca8eb7 2011-09-22 Kyle Harris <kharris@nexus-tech.net>
-zylonite arm pxa b66521a 2011-09-05
-shannon arm sa1100 5df092d 2011-09-05 Rolf Offermanns <rof@sysgo.de>
-modnet50 arm arm720t 9c62815 2011-09-05 Thomas Elste <info@elste.org>
-lpc2292sodimm arm arm720t d1a067a 2011-09-05
-lart arm sa1100 3d57573 2011-09-05 Alex Züpke <azu@sysgo.de>
-impa7 arm arm720t c1f8750 2011-09-05 Marius Gröger <mag@sysgo.de>
-gcplus arm sa1100 2c650e2 2011-09-05 George G. Davis <gdavis@mvista.com>
-evb4510 arm arm720t 26e670e 2011-09-05 Curt Brune <curt@cucy.com>
-ep7312 arm arm720t c8f63b4 2011-09-05 Marius Gröger <mag@sysgo.de>
-dnp1110 arm sa1100 fc5e5ce 2011-09-05 Alex Züpke <azu@sysgo.de>
-SMN42 arm arm720t 6aac646 2011-09-05
-at91rm9200dk arm arm920t 1c85752 2011-07-17
-m501sk arm arm920t b1a2bd4 2011-07-17
-kb9202 arm arm920t 5bd3814 2011-07-17
-csb637 arm arm920t d14af08 2011-07-17
-cmc_pu2 arm arm920t 37a9b4d 2011-07-17
-at91cap9adk arm arm926ejs b550834 2011-07-17 Stelian Pop <stelian@popies.net>
-voiceblue arm arm925t 1b793a4 2011-07-17
-smdk2400 arm arm920t ad218a8 2011-07-17 Gary Jennejohn <garyj@denx.de>
-sbc2410x arm arm920t 1f7f0ed 2011-07-17
-netstar arm arm925t 6ea2405 2011-07-17
-mx1fs2 arm arm920t 6962419 2011-07-17
-lpd7a404 arm lh7a40x 957731e 2011-07-17
-edb9301 arm arm920t 716f7ad 2011-07-17
-edb9302 arm arm920t 716f7ad 2011-07-17
-edb9302a arm arm920t 716f7ad 2011-07-17
-edb9307 arm arm920t 716f7ad 2011-07-17
-edb9307a arm arm920t 716f7ad 2011-07-17
-edb9312 arm arm920t 716f7ad 2011-07-17
-edb9315 arm arm920t 716f7ad 2011-07-17
-edb9315a arm arm920t 716f7ad 2011-07-17
-B2 arm s3c44b0 5dcf536 2011-07-16 Andrea Scian <andrea.scian@dave-tech.it>
-armadillo arm arm720t be28857 2011-07-16 Rowel Atienza <rowel@diwalabs.com>
-assabet arm sa1100 c91e90d 2011-07-16 George G. Davis <gdavis@mvista.com>
-trab arm S3C2400 566e5cf 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 Bénard <eric@eukrea.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>
-CP850 powerpc MPC852 333d86d 2010-10-19 Wolfgang Denk <wd@denx.de>
-logodl ARM PXA2xx 059e778 2010-10-18 August Hoeraendl <august.hoerandl@gmx.at>
-CCM powerpc MPC860 dff07e1 2010-10-06 Wolfgang Grandegger <wg@denx.de>
-PCU_E powerpc MPC860T 544d97e 2010-10-06 Wolfgang Denk <wd@denx.de>
-spieval powerpc MPC5200 69434e4 2010-09-19
-smmaco4 powerpc MPC5200 9ddc3af 2010-09-19
-HMI10 powerpc MPC823 77efe35 2010-09-19 Wolfgang Denk <wd@denx.de>
-GTH powerpc MPC860 0fe247b 2010-07-17 Thomas Lange <thomas@corelatus.se>
-AmigaOneG3SE 953b7e6 2010-06-23
-suzaku microblaze 4f18060 2009-10-03 Yasushi Shoji <yashi@atmark-techno.com>
-XUPV2P microblaze 8fab49e 2008-12-10 Michal Simek <monstr@monstr.eu>
-MVS1 powerpc MPC823 306620b 2008-08-26 Andre Schwarz <andre.schwarz@matrix-vision.de>
-adsvix ARM PXA27x 7610db1 2008-07-30 Adrian Filipi <adrian.filipi@eurotech.com>
-R5200 ColdFire 48ead7a 2008-03-31 Zachary P. Landau <zachary.landau@labxtechnologies.com>
-CPCI440 powerpc 440GP b568fd2 2007-12-27 Matthias Fuchs <matthias.fuchs@esd-electronics.com>
-PCIPPC2 powerpc MPC740/MPC750 - - Wolfgang Denk <wd@denx.de>
+Board Arch CPU Commit Removed Last known maintainer/contact
+=================================================================================================
+ns9750dev arm arm926ejs - - Markus Pietrek <mpietrek@fsforth.de>
+AMX860 powerpc mpc860 1b0757e 2012-10-28 Wolfgang Denk <wd@denx.de>
+c2mon powerpc mpc855 1b0757e 2012-10-28 Wolfgang Denk <wd@denx.de>
+ETX094 powerpc mpc850 1b0757e 2012-10-28 Wolfgang Denk <wd@denx.de>
+IAD210 powerpc mpc860 1b0757e 2012-10-28 -
+LANTEC powerpc mpc850 1b0757e 2012-10-28 Wolfgang Denk <wd@denx.de>
+SCM powerpc mpc8260 1b0757e 2012-10-28 Wolfgang Grandegger <wg@denx.de>
+SX1 arm arm925t 53c4154 2012-10-26
+TQM85xx powerpc MPC85xx d923a5d 2012-10-04 Stefan Roese <sr@denx.de>
+apollon arm omap24xx 535c74f 2012-09-18 Kyungmin Park <kyungmin.park@samsung.com>
+tb0229 mips mips32 3f3110d 2011-12-12
+rmu powerpc MPC850 fb82fd7 2011-12-07 Wolfgang Denk <wd@denx.de>
+OXC powerpc MPC8240 309a292 2011-12-07
+BAB7xx powerpc MPC740/MPC750 c53043b 2011-12-07 Frank Gottschling <fgottschling@eltec.de>
+xm250 arm pxa c746cdd 2011-25-11
+pleb2 arm pxa b185a1c 2011-25-11
+cradle arm pxa 4e24f8a 2011-25-11 Kyle Harris <kharris@nexus-tech.net>
+cerf250 arm pxa a3f1241 2011-25-11 Prakash Kumar <prakash@embedx.com>
+mpq101 powerpc mpc85xx e877fab 2011-10-23 Alex Dubov <oakad@yahoo.com>
+ixdpg425 arm ixp 0ca8eb7 2011-09-22 Stefan Roese <sr@denx.de>
+ixdp425 arm ixp 0ca8eb7 2011-09-22 Kyle Harris <kharris@nexus-tech.net>
+zylonite arm pxa b66521a 2011-09-05
+shannon arm sa1100 5df092d 2011-09-05 Rolf Offermanns <rof@sysgo.de>
+modnet50 arm arm720t 9c62815 2011-09-05 Thomas Elste <info@elste.org>
+lpc2292sodimm arm arm720t d1a067a 2011-09-05
+lart arm sa1100 3d57573 2011-09-05 Alex Züpke <azu@sysgo.de>
+impa7 arm arm720t c1f8750 2011-09-05 Marius Gröger <mag@sysgo.de>
+gcplus arm sa1100 2c650e2 2011-09-05 George G. Davis <gdavis@mvista.com>
+evb4510 arm arm720t 26e670e 2011-09-05 Curt Brune <curt@cucy.com>
+ep7312 arm arm720t c8f63b4 2011-09-05 Marius Gröger <mag@sysgo.de>
+dnp1110 arm sa1100 fc5e5ce 2011-09-05 Alex Züpke <azu@sysgo.de>
+SMN42 arm arm720t 6aac646 2011-09-05
+at91rm9200dk arm arm920t 1c85752 2011-07-17
+m501sk arm arm920t b1a2bd4 2011-07-17
+kb9202 arm arm920t 5bd3814 2011-07-17
+csb637 arm arm920t d14af08 2011-07-17
+cmc_pu2 arm arm920t 37a9b4d 2011-07-17
+at91cap9adk arm arm926ejs b550834 2011-07-17 Stelian Pop <stelian@popies.net>
+voiceblue arm arm925t 1b793a4 2011-07-17
+smdk2400 arm arm920t ad218a8 2011-07-17 Gary Jennejohn <garyj@denx.de>
+sbc2410x arm arm920t 1f7f0ed 2011-07-17
+netstar arm arm925t 6ea2405 2011-07-17
+mx1fs2 arm arm920t 6962419 2011-07-17
+lpd7a404 arm lh7a40x 957731e 2011-07-17
+edb9301 arm arm920t 716f7ad 2011-07-17
+edb9302 arm arm920t 716f7ad 2011-07-17
+edb9302a arm arm920t 716f7ad 2011-07-17
+edb9307 arm arm920t 716f7ad 2011-07-17
+edb9307a arm arm920t 716f7ad 2011-07-17
+edb9312 arm arm920t 716f7ad 2011-07-17
+edb9315 arm arm920t 716f7ad 2011-07-17
+edb9315a arm arm920t 716f7ad 2011-07-17
+B2 arm s3c44b0 5dcf536 2011-07-16 Andrea Scian <andrea.scian@dave-tech.it>
+armadillo arm arm720t be28857 2011-07-16 Rowel Atienza <rowel@diwalabs.com>
+assabet arm sa1100 c91e90d 2011-07-16 George G. Davis <gdavis@mvista.com>
+trab arm S3C2400 566e5cf 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 Bénard <eric@eukrea.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>
+CP850 powerpc MPC852 333d86d 2010-10-19 Wolfgang Denk <wd@denx.de>
+logodl ARM PXA2xx 059e778 2010-10-18 August Hoeraendl <august.hoerandl@gmx.at>
+CCM powerpc MPC860 dff07e1 2010-10-06 Wolfgang Grandegger <wg@denx.de>
+PCU_E powerpc MPC860T 544d97e 2010-10-06 Wolfgang Denk <wd@denx.de>
+spieval powerpc MPC5200 69434e4 2010-09-19
+smmaco4 powerpc MPC5200 9ddc3af 2010-09-19
+HMI10 powerpc MPC823 77efe35 2010-09-19 Wolfgang Denk <wd@denx.de>
+GTH powerpc MPC860 0fe247b 2010-07-17 Thomas Lange <thomas@corelatus.se>
+AmigaOneG3SE powerpc 74xx_7xx 953b7e6 2010-06-23
+suzaku microblaze - 4f18060 2009-10-03 Yasushi Shoji <yashi@atmark-techno.com>
+XUPV2P microblaze - 8fab49e 2008-12-10 Michal Simek <monstr@monstr.eu>
+MVS1 powerpc MPC823 306620b 2008-08-26 Andre Schwarz <andre.schwarz@matrix-vision.de>
+adsvix ARM PXA27x 7610db1 2008-07-30 Adrian Filipi <adrian.filipi@eurotech.com>
+R5200 ColdFire - 48ead7a 2008-03-31 Zachary P. Landau <zachary.landau@labxtechnologies.com>
+CPCI440 powerpc 440GP b568fd2 2007-12-27 Matthias Fuchs <matthias.fuchs@esd-electronics.com>
+PCIPPC2 powerpc MPC740/MPC750 7c9e89b 2013-02-07 Wolfgang Denk <wd@denx.de>
PCIPPC6 powerpc MPC740/MPC750 - - Wolfgang Denk <wd@denx.de>
diff --git a/doc/SPL/README.am335x-network b/doc/SPL/README.am335x-network
new file mode 100644
index 0000000..e5a198f
--- /dev/null
+++ b/doc/SPL/README.am335x-network
@@ -0,0 +1,92 @@
+USING AM335x NETBOOT FEATURE
+
+ Some boards (like TI AM335x based ones) have quite big on-chip RAM and
+have support for booting via network in ROM. The following describes
+how to setup network booting and then optionally use this support to flash
+NAND and bricked (empty) board with only a network cable.
+
+ I. Building the required images
+ 1. You have to enable generic SPL configuration options (see
+docs/README.SPL) as well as CONFIG_SPL_NET_SUPPORT,
+CONFIG_ETH_SUPPORT, CONFIG_SPL_LIBGENERIC_SUPPORT and
+CONFIG_SPL_LIBCOMMON_SUPPORT in your board configuration file to build
+SPL with support for booting over the network. Also you have to enable
+the driver for the NIC used and CONFIG_SPL_BOARD_INIT option if your
+board needs some board-specific initialization (TI AM335x EVM does).
+If you want SPL to use some Vendor Class Identifier (VCI) you can set
+one with CONFIG_SPL_NET_VCI_STRING option. am335x_evm configuration
+comes with support for network booting preconfigured.
+ 2. Define CONFIG_BOOTCOMMAND for your board to load and run debrick
+script after boot:
+#define CONFIG_BOOTCOMMAND \
+ "setenv autoload no; " \
+ "bootp; " \
+ "if tftp 80000000 debrick.scr; then " \
+ "source 80000000; " \
+ "fi"
+(Or create additional board configuration with such option).
+ 3. Build U-Boot as usual
+ $ make <your_board_name>
+ You will need u-boot.img and spl/u-boot.bin images to perform
+network boot. Copy them to u-boot-restore.img and
+u-boot-spl-restore.bin respectively to distinguish this version
+(with automatic restore running) from the main one.
+
+ II. Host configuration.
+ 1. Setup DHCP server (recommended server is ISC DHCPd).
+ - Install DHCP server and setup it to listen on the interface you
+chose to connect to the board (usually configured in
+/etc/default/dhcpd or /etc/default/isc-dhcp-server). Make sure there
+are no other active DHCP servers in the same network segment.
+ - Edit your dhcpd.conf and subnet declaration matching the address
+on the interface. Specify the range of assigned addresses and bootfile
+to use. IMPORTANT! Both RBL and SPL use the image filename provided
+in the BOOTP reply but obviously they need different images (RBL needs
+raw SPL image -- u-boot-spl-restore.bin while SPL needs main U-Boot
+image -- u-boot-restore.img). So you have to configure DHCP server to
+provide different image filenames to RBL and SPL (and possibly another
+one to main U-Boot). This can be done by checking Vendor Class
+Identifier (VCI) set by BOOTP client (RBL sets VCI to "DM814x ROM v1.0"
+and you can set VCI used by SPL with CONFIG_SPL_NET_VCI_STRING option,
+see above).
+ - If you plan to use TFTP server on another machine you have to set
+server-name option to point to it.
+ - Here is sample configuration for ISC DHCPd, assuming the interface
+used to connect to the board is eth0, and it has address 192.168.8.1:
+
+subnet 192.168.8.0 netmask 255.255.255.0 {
+ range dynamic-bootp 192.168.8.100 192.168.8.199;
+
+ if substring (option vendor-class-identifier, 0, 10) = "DM814x ROM" {
+ filename "u-boot-spl-restore.bin";
+ } elsif substring (option vendor-class-identifier, 0, 17) = "AM335x U-Boot SPL" {
+ filename "u-boot-restore.img";
+ } else {
+ filename "uImage";
+ }
+}
+
+ 2. Setup TFTP server.
+ Install TFTP server and put image files to it's root directory
+(likely /tftpboot or /var/lib/tftpboot or /srv/tftp). You will need
+u-boot.img and spl/u-boot-spl-bin files from U-Boot build directory.
+
+ III. Reflashing (debricking) the board.
+ 1. Write debrick script. You will need to write a script that will
+be executed after network boot to perform actual rescue actions. You
+can use usual U-Boot commands from this script: tftp to load additional
+files, nand erase/nand write to erase/write the NAND flash.
+
+ 2. Create script image from your script. From U-Boot build directory:
+
+$ ./tools/mkimage -A arm -O U-Boot -C none -T script -d <your script> debrick.scr
+
+This will create debrick.scr file with your script inside.
+
+ 3. Copy debrick.scr to TFTP root directory. You also need to copy
+there all the files your script tries to load via TFTP. Example script
+loads u-boot.img and MLO. You have to create these files doing regular
+(not restore_flash) build and copy them to tftpboot directory.
+
+ 4. Boot the board from the network, U-Boot will load debrick script
+and run it after boot.
diff --git a/doc/driver-model/UDM-serial.txt b/doc/driver-model/UDM-serial.txt
index c6a8ab0..ef71fea 100644
--- a/doc/driver-model/UDM-serial.txt
+++ b/doc/driver-model/UDM-serial.txt
@@ -86,7 +86,7 @@ III) Analysis of in-tree drivers
7) ns9750_serial.c
------------------
- No support for CONFIG_SERIAL_MULTI. Simple conversion possible.
+ Unmaintained port. Code got removed.
8) opencores_yanu.c
-------------------