LinuxPPC-Dev Archive on lore.kernel.org
 help / color / Atom feed
From: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
To: Daniel Axtens <dja@axtens.net>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>,
	bala24@linux.ibm.com, paulus@samba.org, sandipan@linux.ibm.com,
	jniethe5@gmail.com, naveen.n.rao@linux.vnet.ibm.com,
	linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH v5 1/5] powerpc/sstep: Emulate prefixed instructions only when CPU_FTR_ARCH_31 is set
Date: Wed, 14 Oct 2020 13:04:19 +0530
Message-ID: <11209037-6031-6908-a521-f73182ad5300@linux.ibm.com> (raw)
In-Reply-To: <877drvwocx.fsf@dja-thinkpad.axtens.net>

Hi Daniel,

On 10/12/20 7:14 PM, Daniel Axtens wrote:
> Hi,
> 
> To review this, I looked through the supported instructions to see if
> there were any that I thought might have been missed.
> 
> I didn't find any other v3.1 ones, although I don't have a v3.1 ISA to
> hand so I was basically looking for instructions I didn't recognise.
> 
> I did, however, find a number of instructions that are new in ISA 3.0
> that aren't guarded:
> 
>   - addpcis
>   - lxvl/stxvl
>   - lxvll/stxvll
>   - lxvwsx
>   - stxvx
>   - lxsipzx
>   - lxvh8x
>   - lxsihzx
>   - lxvb16x/stxvb16x
>   - stxsibx
>   - stxsihx
>   - lxvb16x
>   - lxsd/stxsd
>   - lxssp/stxssp
>   - lxv/stxv
>   
> Also, I don't know how bothered we are about P7, but if I'm reading the
> ISA correctly, lqarx/stqcx. are not supported before ISA 2.07. Likewise
> a number of the vector instructions like lxsiwzx and lxsiwax (and the
> companion stores).
> 
> I realise it's not really the point of this particular patch, so I don't
> think this should block acceptance. What I would like to know - and
> maybe this is something where we need mpe to weigh in - is whether we
> need consistent guards for 2.07 and 3.0. We have some 3.0 guards already
> but clearly not everywhere.

Yes, those needs to be handled properly. Otherwise they can be harmful
when emulated on a non-supporting platform. Will work on it when I get
some time. Thanks for reporting it.

> 
> With all that said - the patch does what it says it does, and looks good
> to me:
> 
> Reviewed-by: Daniel Axtens <dja@axtens.net>

Thanks!
Ravi

  reply index

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-11  5:09 [PATCH v5 0/5] powerpc/sstep: VSX 32-byte vector paired load/store instructions Ravi Bangoria
2020-10-11  5:09 ` [PATCH v5 1/5] powerpc/sstep: Emulate prefixed instructions only when CPU_FTR_ARCH_31 is set Ravi Bangoria
2020-10-11 15:06   ` Sandipan Das
2020-10-12  1:51   ` Daniel Axtens
2020-10-12 11:07     ` Ravi Bangoria
2020-10-12 12:55       ` Daniel Axtens
2020-10-12 13:44   ` Daniel Axtens
2020-10-14  7:34     ` Ravi Bangoria [this message]
2020-10-11  5:09 ` [PATCH v5 2/5] powerpc/sstep: Cover new VSX instructions under CONFIG_VSX Ravi Bangoria
2020-10-11  5:09 ` [PATCH v5 3/5] powerpc/sstep: Support VSX vector paired storage access instructions Ravi Bangoria
2020-10-11  5:09 ` [PATCH v5 4/5] powerpc/ppc-opcode: Add encoding macros for VSX vector paired instructions Ravi Bangoria
2020-10-11  5:09 ` [PATCH v5 5/5] powerpc/sstep: Add testcases for VSX vector paired load/store instructions Ravi Bangoria
2020-12-15 10:49 ` [PATCH v5 0/5] powerpc/sstep: VSX 32-byte " Michael Ellerman

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=11209037-6031-6908-a521-f73182ad5300@linux.ibm.com \
    --to=ravi.bangoria@linux.ibm.com \
    --cc=bala24@linux.ibm.com \
    --cc=dja@axtens.net \
    --cc=jniethe5@gmail.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=naveen.n.rao@linux.vnet.ibm.com \
    --cc=paulus@samba.org \
    --cc=sandipan@linux.ibm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

LinuxPPC-Dev Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linuxppc-dev/0 linuxppc-dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linuxppc-dev linuxppc-dev/ https://lore.kernel.org/linuxppc-dev \
		linuxppc-dev@lists.ozlabs.org linuxppc-dev@ozlabs.org
	public-inbox-index linuxppc-dev

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.ozlabs.lists.linuxppc-dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git