AMD 4.4.5 user manual GDB Interface, Simple Approach, 156

	AMD Confidential
User Manual	November 21st, 2008

The pipe is not created until the first “go” command will be executed. This can be achieved by clicking on the “go” button followed by a click on the “stop” button. This command sequence will setup the named-pipe.

If you try to connect the kernel debugger without setting up the named-pipe as described the kernel debugger will return an error message.

In case you have difficulties to establish a connection, or the connection is unstable, or KD has difficulties to stay in sync with the simulated OS. You can set a multiplier to delay the baud rate. The baud rate is normally modeled based on the time elapsed on the simulated system. The simulated system may be running at 1/100 of normal time which will give longer time delays than the kernel debugger can tolerate. Consequently we provide a way to speed up the modeled baud rate by up to 100 times. For example to delay the baud rate by 1/100th of normal you would use the following automation command:

Serial:1.SetMultiplier 1

By default, the multiplier is 100 which means the modeled rate is unchanged. The user may set it in the range 1 to 100. When set to 1, the modeled rate is 100 times faster than the baud rate, so the system delays will be that much shorter. See also Section A.7.10, “Serial”, on page 235.

The following command will connect the kernel debugger to the simulator using a pipe as communication channel:

C:\Program Files\Debugging Tools for Windows 64-bit\kd –k com:pipe,port=\\.\pipe\SimNow.Com1

We recommend not starting the kernel debugger too early. To achieve best results launch the kernel debugger after the O/S kernel has loaded and it is trying to establish a connection with the kernel debugger.

11.2 GDB Interface

Getting the gdb interface in the simulator to work involves a sequence of commands in both the simulator and gdb. The current implementation requires the simulator to be started and told to be ready for gdb to connect and then having gdb connect. As long as the gdb command, "target remote ..." is issued last, the interface should be established.

It has been observed that after shutting down the simulator, the port used by the gdb interface may not become immediately available for reuse. If this happens just shut down both the simualtor and gdb and start again and the problem should go away.

11.2.1 Simple Approach

This assumes you are running the simulator and gdb on the same machine.

∙Start the simualtor

156 Chapter 11: Debug Interface