Difference between revisions of "YAMON"

Revision as of 10:37, 16 August 2012

YAMON™ is the ROM monitor used on MIPS Technologies' development boards.

An example of YAMON boot log on a MIPS Malta Board with a 24Kc core:

YAMON ROM Monitor, Revision 02.06.
Copyright (c) 1999-2004 MIPS Technologies, Inc. - All Rights Reserved.

For a list of available commands, type 'help'.

Compilation time =              Mar 23 2004  16:50:44
Board type/revision =           0x02 (Malta) / 0x00
Core board type/revision =      0x07 (CoreFPGA-2) / 0x00
System controller/revision =    MIPS SOC-it 101 OCP / 1.3   SDR-FW-1:1
FPGA revision =                 0x0001
MAC address =                   00.d0.a0.00.04.2b
Board S/N =                     0000000819
PCI bus frequency =             33.33 MHz
Processor Company ID/options =  0x01 (MIPS Technologies, Inc.) / 0x00
Processor ID/revision =         0x93 (MIPS 24Kc) / 0x60
Endianness =                    Little
CPU/Bus frequency =             25 MHz / 25 MHz
Flash memory size =             4 MByte
SDRAM size =                    64 MByte
First free SDRAM address =      0x800b3860

Environment variables

YAMON maintains a set of the environment variables in non-volatile memory. Example of environment variables in YAMON:

YAMON> set

baseboardserial (RO)   0000000819
bootfile        (R/W)
bootprot        (R/W)  tftp
bootserport     (R/W)  tty0
bootserver      (R/W)  0.0.0.0
cpuconfig       (R/W)
ethaddr         (RO)   00.d0.a0.00.04.2b
fpu             (R/W)
gateway         (R/W)  0.0.0.0
ipaddr          (R/W)  10.0.0.100
memsize         (RO)   0x04000000
modetty0        (R/W)  38400,n,8,1,hw
modetty1        (R/W)  38400,n,8,1,hw
prompt          (R/W)  YAMON
start           (R/W)
startdelay      (R/W)
subnetmask      (R/W)  255.255.255.0
yamonrev        (RO)   02.06

User API

YAMON provides a set of functions callable by application. Pointers to these functions are located in a table located at 0x9fc00500.

Booting

An SREC kernel image can be loaded in YAMON as follows:

YAMON> load tftp://<tftp server name>/<srec file in /tftpboot>

for example, if I have a vmlinux.srec in /tftpboot on 10.0.0.139, then:

YAMON> load tftp://10.0.0.139/vmlinux.srec

YAMON> fread tftp://<ipaddr>/<filename> <address>

Load binary image to RAM or flash (depending on address) from TFTP server. The image is a binary file, not in ELF format.

There is also second-stage IDE bootloader mipsboot

External Links

• YAMON page. (You need a free registration to download a documentation and sourcecode)
  • Old link: http://www.mips.com/products/software-tools/system-software/yamon/
• YAMON license
  • Old link: http://www.mips.com/LicenseMapper/Yamon_license