Versioning:
===========
-U-Boot uses a 3 level version number containing a version, a
-sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
-sub-version "34", and patchlevel "4".
+Starting with the release in October 2008, the names of the releases
+were changed from numerical release numbers without deeper meaning
+into a time stamp based numbering. Regular releases are identified by
+names consisting of the calendar year and month of the release date.
+Additional fields (if present) indicate release candidates or bug fix
+releases in "stable" maintenance trees.
-The patchlevel is used to indicate certain stages of development
-between released versions, i. e. officially released versions of
-U-Boot will always have a patchlevel of "0".
+Examples:
+ U-Boot v2009.11 - Release November 2009
+ U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
+ U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
Directory Hierarchy:
/cpu CPU specific files
/arm720t Files specific to ARM 720 CPUs
/arm920t Files specific to ARM 920 CPUs
- /at91rm9200 Files specific to Atmel AT91RM9200 CPU
- /imx Files specific to Freescale MC9328 i.MX CPUs
- /s3c24x0 Files specific to Samsung S3C24X0 CPUs
+ /at91rm9200 Files specific to Atmel AT91RM9200 CPU
+ /imx Files specific to Freescale MC9328 i.MX CPUs
+ /s3c24x0 Files specific to Samsung S3C24X0 CPUs
/arm925t Files specific to ARM 925 CPUs
/arm926ejs Files specific to ARM 926 CPUs
/arm1136 Files specific to ARM 1136 CPUs
/mips Files generic to MIPS architecture
/cpu CPU specific files
/lib Architecture specific library files
- /nios Files generic to Altera NIOS architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/nios2 Files generic to Altera NIOS2 architecture
/cpu CPU specific files
/lib Architecture specific library files
must be defined, to setup the maximum idle timeout for
the SMC.
-- Interrupt driven serial port input:
- CONFIG_SERIAL_SOFTWARE_FIFO
-
- PPC405GP only.
- Use an interrupt handler for receiving data on the
- serial port. It also enables using hardware handshake
- (RTS/CTS) and UART's built-in FIFO. Set the number of
- bytes the interrupt driven input buffer should have.
-
- Leave undefined to disable this feature, including
- disable the buffer and hardware handshake.
-
-- Console UART Number:
- CONFIG_UART1_CONSOLE
-
- AMCC PPC4xx only.
- If defined internal UART1 (and not UART0) is used
- as default U-Boot console.
-
- Boot Delay: CONFIG_BOOTDELAY - in seconds
Delay before automatically booting the default image;
set to -1 to disable autoboot.
#define I2C_DELAY udelay(2)
+ CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
+
+ If your arch supports the generic GPIO framework (asm/gpio.h),
+ then you may alternatively define the two GPIOs that are to be
+ used as SCL / SDA. Any of the previous I2C_xxx macros will
+ have GPIO-based defaults assigned to them as appropriate.
+
+ You should define these to the GPIO value as given directly to
+ the generic GPIO functions.
+
CONFIG_SYS_I2C_INIT_BOARD
When a board is reset during an i2c bus transfer
custom i2c_init_board() routine in boards/xxx/board.c
is run early in the boot sequence.
+ CONFIG_SYS_I2C_BOARD_LATE_INIT
+
+ An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
+ defined a custom i2c_board_late_init() routine in
+ boards/xxx/board.c is run AFTER the operations in i2c_init()
+ is completed. This callpoint can be used to unreset i2c bus
+ using CPU i2c controller register accesses for CPUs whose i2c
+ controller provide such a method. It is called at the end of
+ i2c_init() to allow i2c_init operations to setup the i2c bus
+ controller on the CPU (e.g. setting bus speed & slave address).
+
CONFIG_I2CFAST (PPC405GP|PPC405EP only)
This option enables configuration of bi_iic_fast[] flags
on high Ethernet traffic.
Defaults to 4 if not defined.
+- CONFIG_ENV_MAX_ENTRIES
+
+ Maximum number of entries in the hash table that is used
+ internally to store the environment settings. The default
+ setting is supposed to be generous and should work in most
+ cases. This setting can be used to tune behaviour; see
+ lib/hashtable.c for details.
+
The following definitions that deal with the placement and management
of environment data (variable area); in general, we support the
following configurations:
I2C muxes, you can define here, how to reach this
EEPROM. For example:
- #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
+ #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
EEPROM which holds the environment, is reached over
a pca9547 i2c mux with address 0x70, channel 3.
Please note that the environment is read-only until the monitor
has been relocated to RAM and a RAM copy of the environment has been
-created; also, when using EEPROM you will have to use getenv_r()
+created; also, when using EEPROM you will have to use getenv_f()
until then to read environment variables.
The environment is protected by a CRC32 checksum. Before the monitor
interface is currently active. For example you
can do the following
- => setenv ethact FEC ETHERNET
- => ping 192.168.0.1 # traffic sent on FEC ETHERNET
- => setenv ethact SCC ETHERNET
- => ping 10.0.0.1 # traffic sent on SCC ETHERNET
+ => setenv ethact FEC
+ => ping 192.168.0.1 # traffic sent on FEC
+ => setenv ethact SCC
+ => ping 10.0.0.1 # traffic sent on SCC
ethrotate - When set to "no" U-Boot does not go through all
available network interfaces.
o If neither SROM nor the environment contain a MAC address, an error
is raised.
+If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
+will be programmed into hardware as part of the initialization process. This
+may be skipped by setting the appropriate 'ethmacskip' environment variable.
+The naming convention is as follows:
+"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
Image Formats:
==============
Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
INTEGRITY).
* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
- IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
- Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
+ IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
+ Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
* Compression Type (uncompressed, gzip, bzip2)
* Load Address
* Entry Point
==> U-Boot will use R8 to hold a pointer to the global data
+On Nios II, the ABI is documented here:
+ http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
+
+ ==> U-Boot will use gp to hold a pointer to the global data
+
+ Note: on Nios II, we give "-G0" option to gcc and don't use gp
+ to access small data sections, so gp is free.
+
NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
or current versions of GCC may "optimize" the code too much.
projects / karo-tx-uboot.git / blobdiff