omap35 出现 No more output is seen on the console after "Starting Kernel..." 调试信息

The first problem a user may encounter when booting the kernel, is that no further output after "Starting kernel..." is seen on the console. For example:

## Booting kernel from Legacy Image at 80300000 ...
Image Name:   Linux-2.6.31
Image Type:   ARM Linux Kernel Image (uncompressed)
Data Size:    1750680 Bytes =  1.7 MB
Load Address: 80008000
Entry Point:  80008000
Verifying Checksum ... OK
Loading Kernel Image ... OK
OK

Starting kernel ...

The above console output is printed by the u-boot boot-loader when starting linux and the message "Starting kernel..." is last message that u-boot will print before starting the kernel. The above problem is typically caused by mis-configuring the tty interface that the linux kernel uses by default for displaying the console messages. The default tty interface used the linux kernel for OMAP devices is configured in the kernel menuconfig. You can check the tty interface being used for an OMAP device by viewing the kernel .config file and seeing which CONFIG_OMAP_LL_DEBUG_UARTx is selected. For example, the OMAP3 beagle-board uses UART3 for displaying the console messages. Hence, when using the OMAP3 beagle-board the following should be found in the .config file:

# CONFIG_OMAP_LL_DEBUG_UART1 is not set
# CONFIG_OMAP_LL_DEBUG_UART2 is not set
CONFIG_OMAP_LL_DEBUG_UART3=y

The default tty interface used by the linux kernel for OMAP can be configured by starting the linux menuconfig utility (by executing "make menuconfig") and going to "System Type --> TI OMAP Implementations --> Low-level debug console UART".