On Tuesday, February 25, 2020, Peter Maydell <peter.mayd...@linaro.org>
wrote:
> The "CPU emulation" part of the "Implementation notes" in
> qemu-tech.texi looks like it is documenting what features of various
> CPUs we do or don't emulate. However:
> * it covers only six of our 21 guest architectures
> * the last time anybody updated it for actual content was in
> 2011/2012 for Xtensa; the content for the other five
> architectures is even older, being from 2008 or before!
>
> What we have is out of date, misleading and incomplete.
> Just delete this part of the document rather than trying to
> convert it to rST.
>
> (It would be nice eventually to have documentation of the
> scope and limitations of our emulation; but we will want to
> separate out the generic "system emulation" information from
> the parts that are specific to linux-user anyway, as they will
> be in different manuals.)
>
> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
> ---
I agree with the intent and the outcome of this patch, including the last
paragraph in braces.
FWIW:
Reviewed-by: Aleksandar Markovic <amarko...@wavecomp.com>
qemu-tech.texi | 153 -------------------------------------------------
> 1 file changed, 153 deletions(-)
>
> diff --git a/qemu-tech.texi b/qemu-tech.texi
> index 0380de77b62..35da6a40af1 100644
> --- a/qemu-tech.texi
> +++ b/qemu-tech.texi
> @@ -2,162 +2,9 @@
> @appendix Implementation notes
>
> @menu
> -* CPU emulation::
> * Managed start up options::
> @end menu
>
> -@node CPU emulation
> -@section CPU emulation
> -
> -@menu
> -* x86:: x86 and x86-64 emulation
> -* ARM:: ARM emulation
> -* MIPS:: MIPS emulation
> -* PPC:: PowerPC emulation
> -* SPARC:: Sparc32 and Sparc64 emulation
> -* Xtensa:: Xtensa emulation
> -@end menu
> -
> -@node x86
> -@subsection x86 and x86-64 emulation
> -
> -QEMU x86 target features:
> -
> -@itemize
> -
> -@item The virtual x86 CPU supports 16 bit and 32 bit addressing with
> segmentation.
> -LDT/GDT and IDT are emulated. VM86 mode is also supported to run
> -DOSEMU. There is some support for MMX/3DNow!, SSE, SSE2, SSE3, SSSE3,
> -and SSE4 as well as x86-64 SVM.
> -
> -@item Support of host page sizes bigger than 4KB in user mode emulation.
> -
> -@item QEMU can emulate itself on x86.
> -
> -@item An extensive Linux x86 CPU test program is included
> @file{tests/test-i386}.
> -It can be used to test other x86 virtual CPUs.
> -
> -@end itemize
> -
> -Current QEMU limitations:
> -
> -@itemize
> -
> -@item Limited x86-64 support.
> -
> -@item IPC syscalls are missing.
> -
> -@item The x86 segment limits and access rights are not tested at every
> -memory access (yet). Hopefully, very few OSes seem to rely on that for
> -normal use.
> -
> -@end itemize
> -
> -@node ARM
> -@subsection ARM emulation
> -
> -@itemize
> -
> -@item Full ARM 7 user emulation.
> -
> -@item NWFPE FPU support included in user Linux emulation.
> -
> -@item Can run most ARM Linux binaries.
> -
> -@end itemize
> -
> -@node MIPS
> -@subsection MIPS emulation
> -
> -@itemize
> -
> -@item The system emulation allows full MIPS32/MIPS64 Release 2 emulation,
> -including privileged instructions, FPU and MMU, in both little and big
> -endian modes.
> -
> -@item The Linux userland emulation can run many 32 bit MIPS Linux
> binaries.
> -
> -@end itemize
> -
> -Current QEMU limitations:
> -
> -@itemize
> -
> -@item Self-modifying code is not always handled correctly.
> -
> -@item 64 bit userland emulation is not implemented.
> -
> -@item The system emulation is not complete enough to run real firmware.
> -
> -@item The watchpoint debug facility is not implemented.
> -
> -@end itemize
> -
> -@node PPC
> -@subsection PowerPC emulation
> -
> -@itemize
> -
> -@item Full PowerPC 32 bit emulation, including privileged instructions,
> -FPU and MMU.
> -
> -@item Can run most PowerPC Linux binaries.
> -
> -@end itemize
> -
> -@node SPARC
> -@subsection Sparc32 and Sparc64 emulation
> -
> -@itemize
> -
> -@item Full SPARC V8 emulation, including privileged
> -instructions, FPU and MMU. SPARC V9 emulation includes most privileged
> -and VIS instructions, FPU and I/D MMU. Alignment is fully enforced.
> -
> -@item Can run most 32-bit SPARC Linux binaries, SPARC32PLUS Linux
> binaries and
> -some 64-bit SPARC Linux binaries.
> -
> -@end itemize
> -
> -Current QEMU limitations:
> -
> -@itemize
> -
> -@item IPC syscalls are missing.
> -
> -@item Floating point exception support is buggy.
> -
> -@item Atomic instructions are not correctly implemented.
> -
> -@item There are still some problems with Sparc64 emulators.
> -
> -@end itemize
> -
> -@node Xtensa
> -@subsection Xtensa emulation
> -
> -@itemize
> -
> -@item Core Xtensa ISA emulation, including most options: code density,
> -loop, extended L32R, 16- and 32-bit multiplication, 32-bit division,
> -MAC16, miscellaneous operations, boolean, FP coprocessor, coprocessor
> -context, debug, multiprocessor synchronization,
> -conditional store, exceptions, relocatable vectors, unaligned exception,
> -interrupts (including high priority and timer), hardware alignment,
> -region protection, region translation, MMU, windowed registers, thread
> -pointer, processor ID.
> -
> -@item Not implemented options: data/instruction cache (including cache
> -prefetch and locking), XLMI, processor interface. Also options not
> -covered by the core ISA (e.g. FLIX, wide branches) are not implemented.
> -
> -@item Can run most Xtensa Linux binaries.
> -
> -@item New core configuration that requires no additional instructions
> -may be created from overlay with minimal amount of hand-written code.
> -
> -@end itemize
> -
> @node Managed start up options
> @section Managed start up options
>
> --
> 2.20.1
>
>
>
