Have you implemented a qXfer packet response if not you can do so to use xml description provided by target.
Here is a gdb help link that describe how to client can query target.xml. https://sourceware.org/gdb/onlinedocs/gdb/Retrieving-Descriptions.html#Retrieving-Descriptions On 10 November 2014 19:42, Qu, Strong <stro...@qti.qualcomm.com> wrote: > Thanks, Omair. I did check xml files in Linaro's source > (gdb-linaro-7.6.1-2013.10). In the target.xml file our gdb server sends back > to gdb client, we only include regsiters X0~X30, sp, pc and cpsr. It's close > to gdb-linaro-7.6.1-2013.10\gdb\features\aarch64-core.xml, which is included > in aarch64-without-fpu.xml. I don't know how the server can notify the client > that it does not have FPU supported. So I assume if the target.xml does not > claim feature 'org.gnu.gdb.aarch64.fpu’, it would be deemed as no FPU > supporting. > For now, I added some code in our code to return the value of fpsr and fpcr > to make the gdb client happy. > > Regards, > Strong > > -----Original Message----- > From: Omair Javaid [mailto:omair.jav...@linaro.org] > Sent: Monday, November 10, 2014 3:30 AM > To: Qu, Strong > Cc: linaro-toolchain@lists.linaro.org > Subject: Re: [Question] Should gdb client query FP registers even if gdb > server does not report having org.gnu.gdb.aarch64.fpu feature? > > On 7 November 2014 02:27, Qu, Strong <stro...@qti.qualcomm.com> wrote: >> Hello, >> >> >> >> We have implemented gdb server in one of our project and we are using >> Linaro aarch64-none-elf-gdb.exe as gdb client. Our gdb server will >> response to packet 'qXfer:features:read:target.xml:0,fff' with a xml >> file which only claims feature ‘org.gnu.gdb.aarch64.core’. However, when I >> issue ‘info reg’ >> command with the gdb client, it actually sends out a packet ‘$p42#d6’, >> which is trying to read fpsr if I understand correctly. Is this an >> expected behavior or not? I just want to figure out whether our gdb >> server send some bad info to the gdb client and made the client thinks >> FP registers are valid. I hope I made my question clear and I’m really >> appreciate if anybody can help us on this again. >> >> >> >> Thanks, >> >> >> >> Strong >> >> >> _______________________________________________ >> linaro-toolchain mailing list >> linaro-toolchain@lists.linaro.org >> http://lists.linaro.org/mailman/listinfo/linaro-toolchain >> > > Hi Strong, > > GDB server will receive a register read request based on registers > information given in xml target description on the client side. > > You can find these xml in gdb sources under: binutils-gdb/gdb/features > > If GDB is requesting a read for certain register that you expect it should > not then you have to verify if its there in the xml description or not. > > There is a chance you might have developed your gdbserver implementation with > some version that doesnt match with current version of linaro-gdb. > > I hope this helps. Let me know if you need to know anything further. > > Thanks! > > -- > Omair _______________________________________________ linaro-toolchain mailing list linaro-toolchain@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-toolchain
