also, i think about how to add a device in fs mode.
if add a device, i guess we have to write drivers for it.
how about define some global variant, and take use of them to achieve some goal.
anybody do it?
and how to do?
thanks in advance.
Date: Tue, 18 Dec 2012 19:13:22 -0600
From: shoai...@cs.wisc.edu
To: gem5-users@gem5.org
Subject: [gem5-users] Accessing a device
Hey List,
I am running Full system X86 and the bigger picture is to integrate
accelerators (or co-processors) in gem5. I think starting with
adding devices will be a good starting point.
I have added a device "Hello device" in the system (similar to
procedure listed in ASPLOS tutorial). Since, SouthBridge.py assigns
address to the devices which are connected to the south bridge, so I
have added these lines in SouthBridge.py
========================================
_hello = HelloDevice(pio_addr=x86IOAddress(0x84))
hello = Param.HelloDevice(_hello,"test device")
....................................................................................
self.hello.pio = bus.master
========================================
But I can see that the device is connected to the system in
m5out/config.ini.
=========================================
[system.pc.south_bridge]
type=SouthBridge
children=cmos dma1 hello ide int_lines0 int_lines1
int_lines2 int_lines3 int_lines4 int_lines5 int_lines6 io_apic
keyboard pic1 pic2 pit speaker
cmos=system.pc.south_bridge.cmos
dma1=system.pc.south_bridge.dma1
hello=system.pc.south_bridge.hello
io_apic=system.pc.south_bridge.io_apic
keyboard=system.pc.south_bridge.keyboard
pic1=system.pc.south_bridge.pic1
pic2=system.pc.south_bridge.pic2
pit=system.pc.south_bridge.pit
platform=system.pc
speaker=system.pc.south_bridge.speaker
...................................................................................
[system.pc.south_bridge.hello]
type=HelloDevice
clock=1
pio_addr=9223372036854775940
pio_latency=100000
system=system
pio=system.iobus.master[11]
=========================================
So my question is, how am I suppose to access this device (either at
boot time or as a user). The ASPLOS tutorial mentioned about making
some changes in the ALPHA console for accessing device address at
boot time, do I have to make similar changes in linux kernel ?? Also
in the documentation, it is mentioned about 'BadDevice' which panics
on an access; I am not sure who to access that device either.
Similar questions were asked couple of times in the past but they
were not answered.
http://www.mail-archive.com/gem5-users@gem5.org/msg02222.html
The above post asked about the following code but it gives a
segfault on running it.
========================================
int main(){
volatile int *ptr = (int *) 0x8000000000000084; //device address
*ptr=10;
printf("Device accessed (Value:%d)\n", *ptr);
return 0;
}
========================================
Any help/pointers in this regard will be appreciated.
Thanks
Shoaib
_______________________________________________
gem5-users mailing list
gem5-users@gem5.org
http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
_______________________________________________
gem5-users mailing list
gem5-users@gem5.org
http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
