From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754287Ab3CXO1G (ORCPT ); Sun, 24 Mar 2013 10:27:06 -0400 Received: from mail-ee0-f47.google.com ([74.125.83.47]:60029 "EHLO mail-ee0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754186Ab3CXO1E (ORCPT ); Sun, 24 Mar 2013 10:27:04 -0400 From: Pali =?utf-8?q?Roh=C3=A1r?= To: Tony Lindgren Subject: Re: [PATCH] arm: omap: RX-51: ARM errata 430973 workaround Date: Sun, 24 Mar 2013 15:26:59 +0100 User-Agent: KMail/1.13.7 (Linux/3.5.0-27-generic; KDE/4.10.1; x86_64; ; ) Cc: Nishanth Menon , =?utf-8?q?=D0=98=D0=B2=D0=B0=D0=B9=D0=BB=D0=BE?= =?utf-8?q?_=D0=94=D0=B8=D0=BC=D0=B8=D1=82=D1=80=D0=BE=D0=B2?= , linux@arm.linux.org.uk, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <517283541.62064.1362124023621.JavaMail.apache@mail81.abv.bg> <20130306175120.GP11806@atomide.com> <201303062013.16302@pali> In-Reply-To: <201303062013.16302@pali> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart9820409.euZJscsTbO"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201303241526.59275@pali> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --nextPart9820409.euZJscsTbO Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wednesday 06 March 2013 20:13:15 Pali Roh=C3=A1r wrote: > On Wednesday 06 March 2013 18:51:21 Tony Lindgren wrote: > > * Pali Roh=C3=A1r [130306 06:13]: > > > On Monday 04 March 2013 19:58:06 Tony Lindgren wrote: > > > > * Nishanth Menon [130301 06:42]: > > > > > On Fri, Mar 1, 2013 at 1:47 AM, =D0=98=D0=B2=D0=B0=D0=B9=D0=BB=D0= =BE =D0=94=D0=B8=D0=BC=D0=B8=D1=82=D1=80=D0=BE=D0=B2 > > >=20 > > > wrote: > > > > > > They look similar, but they are not equivalent :). > > > > > > The first major difference is here (code taken from > > > > > > omap-smc.S) > > > > > >=20 > > > > > >> ENTRY(omap_smc2) > > > > > >>=20 > > > > > >> stmfd sp!, {r4-r12, lr} > > > > > >> mov r3, r2 > > > > > >> mov r2, r1 > > > > > >> mov r1, #0x0 @ Process ID > > > > > >> mov r6, #0xff > > > > > >> mov r12, #0x00 @ Secure Service > > > > > >> ID > > > > > >=20 > > > > > > Always zero, while RX51 PPA expects a real value. I > > > > > > wonder if it is a bug, but anyway I don't see the id > > > > > > parameter (R0) used. > > > > > >=20 > > > > > >> mov r7, #0 > > > > > >> mcr p15, 0, r7, c7, c5, 6 > > > > > >=20 > > > > > > According to ARM TRM, this is "Invalidate entire > > > > > > branch predictor array"(IIUC). NFC why it is needed > > > > > > here, but this will not work on RX-51 until IBE bit > > > > > > in ACR is set. > > > > > >=20 > > > > > >> dsb > > > > > >> dmb > > > > > >> smc #0 > > > > > >=20 > > > > > > RX-51 needs smc #1 ;) > > > > > >=20 > > > > > >> ldmfd sp!, {r4-r12, pc} > > > > > >=20 > > > > > > The next major difference is that RX-51 expects > > > > > > parameter count passed in R3[0] to be the count of > > > > > > the remaining parameters +1, but > > > > > > omap_secure_dispatcher (in omap-secure.c) is passing > > > > > > the exact count of the remaining parameters. > > > > > >=20 > > > > > > I guess all of the above problems can be > > > > > > fixed/workarounded, but I wonder does it worth. Not > > > > > > to say that I don't have BB around to test if the > > > > > > code still works if I make changes to > > > > > > omap2-secure.c/omap-smc.S :) > > > > >=20 > > > > > Yep, that was my point - instead of introducing new > > > > > functions, extending the existing functions to handle > > > > > new requirements is better solution, IMHO. > > > >=20 > > > > I think there have been patches posted for ARM generic > > > > SMC handling. Might be worth looking at those a bit and > > > > see if this can be made generic. I think only the SMC > > > > call numbering is different for various SoCs? > > > >=20 > > > > Regards, > > > >=20 > > > > Tony > > >=20 > > > Hi Tony, where are patches for ARM generic SMC handling? > >=20 > > Sorry don't have the link available, but I recall seeing > > some patch on linux-arm-kernel within past six months that > > added a generic smc function.. Or maybe I was dreaming or > > something. > >=20 > > Regards, > >=20 > > Tony >=20 > I am not able to find that patch... Hi Tony, it is possible to upstream errata 430973 workaround for RX-51? =2D-=20 Pali Roh=C3=A1r pali.rohar@gmail.com --nextPart9820409.euZJscsTbO Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEABECAAYFAlFPDTMACgkQi/DJPQPkQ1KLNQCdEgRl21FJihcjkTzMoUd8PFg+ gzcAn0iHVxeRnJSQm9a5Bs6+KzvAWZjP =V59O -----END PGP SIGNATURE----- --nextPart9820409.euZJscsTbO--