From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from eggs.gnu.org (eggs.gnu.org [IPv6:2001:470:142:3::10]) by sourceware.org (Postfix) with ESMTPS id 73C223858D35 for ; Sat, 1 Jul 2023 08:58:11 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 73C223858D35 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gnu.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gnu.org Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qFWQk-00086q-H8; Sat, 01 Jul 2023 04:58:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=TjpG5iKyqMTGjm50m67IXhr7Hp6YJRwEr6kcu+7Ix3g=; b=a40bpJH1txXS IFPpITs+Y9PJSmX5pTNWa2G/Q71tbFn52AbI97fYxGgnsleIpq5z6wJ6YzqM5TxvJdPZeUz8hnn6q 4Luj8CFQEXGV7bykDTDpi1FZBvJFek6QU2ymXf/jC2QoRm2AVJUuj6NYnRif1mGzrOil+awMvzGjZ cpj7iK2TSIIOZYomW9ajs3XrYmCGtcTTAunJjxCO2Wg7xGey4oJuK6h/tE9ls3IZIllbxGEWxTOPr vCTJRmOJnAE9jEwT11IpHYKg2f5vknHiT4hL29VLM9O4YPwPGo7jm6O93DelErtVO6Tvl/f1O4FMs AbWozvSV/6OgbBrDw+z2Tg==; Received: from [87.69.77.57] (helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qFWQk-0003de-13; Sat, 01 Jul 2023 04:58:10 -0400 Date: Sat, 01 Jul 2023 11:58:42 +0300 Message-Id: <83fs68qa7x.fsf@gnu.org> From: Eli Zaretskii To: Luis Machado Cc: gdb-patches@sourceware.org In-Reply-To: <20230630134616.1238105-17-luis.machado@arm.com> (message from Luis Machado via Gdb-patches on Fri, 30 Jun 2023 14:46:16 +0100) Subject: Re: [PATCH v3 16/16] [gdb/docs] sme: Document SME registers and features References: <20230630134616.1238105-1-luis.machado@arm.com> <20230630134616.1238105-17-luis.machado@arm.com> X-Spam-Status: No, score=-7.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,RCVD_IN_BARRACUDACENTRAL,SPF_HELO_PASS,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: > Date: Fri, 30 Jun 2023 14:46:16 +0100 > From: Luis Machado via Gdb-patches > > Updates since v2: > > - More adjustments based on reviews. > - Fixed incorrect number of tile pseudo-registers. > - Fixed naming of tile slice pseudo-registers. > - More detail about SME and how gdb implements it. > - Attempted to clarify the text a bit more. > > Updates since v1: > > - Made SME text more thorough. > - Adjusted text based on upstream reviews. > - Fixed documentation errors (missing itemization for SME registers). > > Provide documentation for the SME feature and other information that > should be useful for users that need to debug a SME-capable target. > > --- > gdb/NEWS | 11 ++ > gdb/doc/gdb.texinfo | 249 ++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 260 insertions(+) Thanks. > diff --git a/gdb/NEWS b/gdb/NEWS > index fd42864c692..720008a5d97 100644 > --- a/gdb/NEWS > +++ b/gdb/NEWS > @@ -3,6 +3,17 @@ > > *** Changes since GDB 13 > > +* GDB now supports the AArch64 Scalable Matrix Extension (SME), which includes > + a new matrix register named ZA, a new thread register TPIDR2 and a new vector > + length register SVG (streaming vector granule). GDB also supports tracking > + ZA state across signal frames. > + > + Some features are still under development or are dependent on ABI specs that > + are still in alpha stage. For example, manual function calls with ZA state > + don't have any special handling, and tracking of SVG changes based on > + DWARF information is still not implemented, but there are plans to do so in > + the future. > + > * The AArch64 'org.gnu.gdb.aarch64.pauth' Pointer Authentication feature string > has been deprecated in favor of the 'org.gnu.gdb.aarch64.pauth_v2' feature > string. This part is OK. > +@item > +@var{vl}: The vector length, in bytes. It defines the size of each @code{z} > +register. ^^^ That should be "Z", in upper case. > +(@var{svl} for short). @xref{vl} @xref{svl} ^ ^ Periods missing there. Also, please leave two spaces between sentences. > +The minimum size of the @code{ZA} register is 16 x 16 (256) bytes, and the > +maximum size is 256 x 256 (65536) bytes. In streaming mode, with bit @sc{sm} > +set, the size of the @code{ZA} register is the size of all the SVE @code{z} > +registers combined. ^^^ That should be "Z", upper-case. > +There is a total of 31 @code{ZA} tile pseudo-registers. They are > +@code{za0b}, @code{za0h} through @code{za1h}, @code{zas0} through @code{zas3}, > +@code{zad0} through @code{zad7} and @code{zaq0} through @code{zaq15}. These pseudo-registers should also be named in upper-case, right? > +The tile slice pseudo-registers have the following naming pattern: > +@code{za<@var{tile number}><@var{direction}><@var{qualifier}> > +<@var{slice number}>}. Likewise here. > +One such example is calling functions in the program being debugged by > +@value{GDBN}. Such calls are not @acronym{SME}-aware and thus don't take into > +account the @code{SVCR} pseudo-register bits nor the @code{ZA} register > +contents. @xref{Calling} ^ Period missing there. > +The @url{https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst#the-za-lazy-saving-scheme, > +lazy saving scheme} involving the @code{tpidr2} register is not yet supported > +by @value{GDBN}, though the @code{tpidr2} register is known and supported > +by @value{GDBN}. The "tpidr2" register name should be in upper-case. > +Lastly, an important limitation for @code{gdbserver} is its inability to > +communicate @var{svl} changes to @value{GDBN}. This means @code{gdbserver}, > +even though it is capable of adjusting its internal caches to reflect a change Please use @command{gdbserver} instead of @code. > +The @samp{org.gnu.gdb.aarch64.sme} feature is optional. If present, > +it should contain registers @code{ZA}, @code{SVG} and @code{SVCR}. > +@xref{AArch64 SME} ^ Period missing there. > +@item > +@code{ZA} is a register represented by a vector of @var{svl}x@var{svl} > +bytes. @xref{svl} ^ And there. > +Bit 1 (@sc{ZA}) shows whether the @code{ZA} register state is active (in use) or > +not. > +@xref{aarch64 sme svcr} ^ And there. Reviewed-By: Eli Zaretskii