U-Boot
ATCA-F140 Series Installation and Use (6806800M67S)
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This feature can be useful in many situations, including:
Analyzing kernel logs after a Linux kernel panic
Defining a particular memory region for the persistent storage of application
specific data
Analyzing Kernel Log Files after a Kernel Panic
If the Linux OS running on the ATCA-F140 indicates a kernel panic and you wish to analyze
the cause, then you can issue a reset (using the face plate button for example) and
subsequently analyze kernel log files. Because of the persistent memory feature, these log
files are still available in the memory.
To analyze the kernel log files:
1.
Issue a reset.
2.
Connect to U-Boot. For more information, see
3.
Using the kernel memory map, find the memory addresses of the kernel logs.
4. To display the kernel logfile at any of these memory addresses, enter the following
command:
.printf (<memory address)
The persistent memory feature can also be useful in the storage of application-specific
data. Use the standard U-Boot variable
pram
to reserve a memory region (at the end of the
physical memory). This allows the reserved region to not be overwritten by U-Boot. U-Boot
reports less memory to the Linux kernel (through the
mem
parameter) so that Linux will not
use it either.
5.6
Memory Map
The following table shows the physical address map of the ATCA-F140.
Table 5-1
Physical Address Map
Device
Start Address
Size
DDR3-RAM
0x00000000
Max. 4GByte
Active boot flash
0xE0000000
32Mbytes
Standby boot flash
0xE2000000
32Mbytes
BITS1
0xFFA00000
32Kbytes
BITS2
0xFFA100000
32Kbytes
FPGA
0xFFDF0000
32Kbytes
P2020 CPU
0xFFE00000
32Kbytes
