This feature is useful when your board uses different mii buses for different
phys and all (or a part) of these buses are implemented via bit-banging mode.
The driver requires that the following macros should be defined into the board
configuration file:
CONFIG_BITBANGMII - Enable the miiphybb driver
CONFIG_BITBANGMII_MULTI - Enable the multi bus support
If the CONFIG_BITBANGMII_MULTI is not defined, the board's config file needs
to define at least the following macros:
MII_INIT - Generic code to enable the MII bus (optional)
MDIO_DECLARE - Declaration needed to access to the MDIO pin (optional)
MDIO_ACTIVE - Activate the MDIO pin as out pin
MDIO_TRISTATE - Activate the MDIO pin as input/tristate pin
MDIO_READ - Read the MDIO pin
MDIO(v) - Write v on the MDIO pin
MDC_DECLARE - Declaration needed to access to the MDC pin (optional)
MDC(v) - Write v on the MDC pin
The previous macros make the driver compatible with the previous version
(that didn't support the multi-bus).
When the CONFIG_BITBANGMII_MULTI is also defined, the board code needs to fill
the bb_miiphy_buses[] array with a record for each required bus and declare
the bb_miiphy_buses_num variable with the number of mii buses.
The record (struct bb_miiphy_bus) has the following fields/callbacks (see
miiphy.h for details):
char name[] - The symbolic name that must be equal to the MII bus
registered name
int (*init)() - Initialization function called at startup time (just
before the Ethernet initialization)
int (*mdio_active)() - Activate the MDIO pin as output
int (*mdio_tristate)() - Activate the MDIO pin as input/tristate pin
int (*set_mdio)() - Write the MDIO pin
int (*get_mdio)() - Read the MDIO pin
int (*set_mdc)() - Write the MDC pin
int (*delay)() - Delay function
void *priv - Private data used by board specific code
The board code will look like:
struct bb_miiphy_bus bb_miiphy_buses[] = {
{ .name = miibus#1, .init = b1_init, .mdio_active = b1_mdio_active, ... },
{ .name = miibus#2, .init = b2_init, .mdio_active = b2_mdio_active, ... },
...
int bb_miiphy_buses_num = sizeof(bb_miiphy_buses) /
sizeof(bb_miiphy_buses[0]);
Signed-off-by: Luigi 'Comio' Mantellini <luigi.mantellini@idf-hit.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
Storage of the board specific values (ethaddr...)
-------------------------------------------------
The board specific environment variables that should be unique
for each individual board, can be stored in the I2C EEPROM. This
will be done from offset 0x80 with the length of 0x80 bytes. The
following command can be used to store the values here:
=> setdef de:20:6a:ed:e2:72 de:20:6a:ed:e2:73 AB0001
ethaddr eth1addr serial#
Now those 3 values are stored into the I2C EEPROM. A CRC is added
to make sure that the values get not corrupted.
SW-Reset Pushbutton handling:
-----------------------------
The SW-reset push button is connected to a GPIO input too. This
way U-Boot can "see" how long the SW-reset was pressed, and a
specific action can be taken. Two different actions are supported:
a) Release after more than 5 seconds and less then 10 seconds:
-> Run POST
Please note, that the POST test will take a while (approx. 1 min
on the 128MByte board). This is mainly due to the system memory
test.
b) Release after more than 10 seconds:
-> Restore factory default settings
The factory default values are restored. The default environment
variables are restored (ipaddr, serverip...) and the board
specific values (ethaddr, eth1addr and serial#) are restored
to the environment from the I2C EEPROM. Also a bootline parameter
is added to the Linux bootline to signal the Linux kernel upon
the next startup, that the factory defaults should be restored.
The command to check this sw-reset status and act accordingly is
=> chkreset
This command is added to the default "bootcmd", so that it is called
automatically upon startup.
Also, the 2 LED's are used to indicate the current status of this
command (time passed since pushing the button). When the POST test
will be run, the green LED will be switched off, and when the
factory restore will be initiated, the reg LED will be switched off.
Loggin of POST results:
-----------------------
The results of the POST tests are logged in a logbuffer located at the end
of the onboard memory. It can be accessed with the U-Boot command "log":
=> log show
<4>POST memory PASSED
<4>POST cache PASSED
<4>POST cpu PASSED
<4>POST uart PASSED
<4>POST ethernet PASSED
The DENX Linux kernel tree has support for this log buffer included. Exactly
this buffer is used for logging of all kernel messages too. By enabling the
compile time option "CONFIG_LOGBUFFER" this support is enabled. This way you
can access the U-Boot log messages from Linux too.
2007-08-10, Stefan Roese <sr@denx.de>
4ba31ab33a