ppc4xx: Add initial Zeus (PPC405EP) board support

Signed-off-by: Stefan Roese <sr@denx.de>

1 files changed, 73 insertions, 0 deletions

diff --git a/doc/README.zeus b/doc/README.zeus
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+
+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>