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#502 TR6 & TR7 registers are not handled
I checked bochs's source code and I could not find any info about 386 test registers, at least tr6 and tr7 (see https://en.wikipedia.org/wiki/Test_register ).
I'd like to add them myself, but I don't know where to start.
Can someone guide me a bit?
386 is not project priority and these TR registers do not exists in newer products
Also they are not documented.
The wiki says TR6 is used for TLB testing. How ? There is no description anywhere.
Actually there is some info out there:
https://retrocomputing.stackexchange.com/questions/21963/how-were-the-test-registers-used-on-the-i386-and-the-i486
https://www.scs.stanford.edu/05au-cs240c/lab/i386/s10_06.htm
http://www.bitsavers.org/components/ti/TI486/1993_TI486_Microprocessor_Reference_Guide.pdf
http://www.bitsavers.org/components/cyrix/Cyrix_Cx486DLC_Data_Sheet_May92.pdf
etc.
These registers are used by 386/486 bioses and without supporting these registers it's not possible to use these bioses with bochs.
I faced this problem when I tried to debug a bios for 386 ;-).
As I said, if is not too complicated, I'd like to implement it myself if someone can guide me trough the code.
Just follow CR and DR write methods in CPU, file crregs.cc
Thanks, for the info it helped a lot.
Here https://github.com/bochs-emu/Bochs/pull/68 is the pull request.
Now bochs runs correctly my bios. There is only on bug left, the disassembly doesn't work as expected and I don't have any idea why ...