From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0940BC433EF for ; Thu, 30 Sep 2021 08:08:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2D42615A7 for ; Thu, 30 Sep 2021 08:08:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349005AbhI3IJo (ORCPT ); Thu, 30 Sep 2021 04:09:44 -0400 Received: from relay8-d.mail.gandi.net ([217.70.183.201]:49613 "EHLO relay8-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348910AbhI3IJn (ORCPT ); Thu, 30 Sep 2021 04:09:43 -0400 Received: (Authenticated sender: thomas.perrot@bootlin.com) by relay8-d.mail.gandi.net (Postfix) with ESMTPSA id 48D641BF207; Thu, 30 Sep 2021 08:07:59 +0000 (UTC) Message-ID: <54c063613fe63282a1c26b312c772e89b662eae6.camel@bootlin.com> Subject: Re: [PATCH] bus: mhi: pci_generic: increase timeout value for operations to 24000ms From: Thomas Perrot To: Aleksander Morgado , Manivannan Sadhasivam Cc: linux-arm-msm , hemantk@codeaurora.org, Loic Poulain , stable Date: Thu, 30 Sep 2021 10:07:57 +0200 In-Reply-To: References: <20210805140231.268273-1-thomas.perrot@bootlin.com> <73A52D61-FCAB-4A2B-BA96-0117F6942842@linaro.org> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-GLaBsdgJhSTUDVRwrQzr" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org --=-GLaBsdgJhSTUDVRwrQzr Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hello, On Wed, 2021-09-29 at 15:17 +0200, Aleksander Morgado wrote: > Hey Mani, >=20 > > > > diff --git a/drivers/bus/mhi/pci_generic.c > > > > b/drivers/bus/mhi/pci_generic.c > > > > index 4dd1077354af..e08ed6e5031b 100644 > > > > --- a/drivers/bus/mhi/pci_generic.c > > > > +++ b/drivers/bus/mhi/pci_generic.c > > > > @@ -248,7 +248,7 @@ static struct mhi_event_config > > > > modem_qcom_v1_mhi_events[] =3D { > > > >=20 > > > > =C2=A0 static const struct mhi_controller_config > > > > modem_qcom_v1_mhiv_config =3D { > > > > =C2=A0=C2=A0=C2=A0=C2=A0 .max_channels =3D 128, > > > > -=C2=A0=C2=A0=C2=A0 .timeout_ms =3D 8000, > > > > +=C2=A0=C2=A0=C2=A0 .timeout_ms =3D 24000, > > >=20 > > >=20 > > > This modem_qcom_v1_mhiv_config config applies to all generic SDX24, > > > SDX55 and SDX65 modules. > > > Other vendor-branded SDX55 based modules in this same file (Foxconn > > > SDX55, MV31), have 20000ms as timeout. > > > Other vendor-branded SDX24 based modules in this same file (Quectel > > > EM12xx), have also 20000ms as timeout. > > > Maybe it makes sense to have a common timeout for all? > > >=20 > >=20 > > Eventhough the baseport coming from Qualcomm for the modem chipsets > > are same, it is possible that the vendors might have customized the > > firmware for their own usecase. That could be the cause of the delay > > for modem booting. > >=20 > > So I don't think we should use the same timeout of 2400ms for all > > modems. > >=20 >=20 > Please note it's 24000ms what's being suggested here, not 2400ms. >=20 > > > Thomas, is the 24000ms value taken from experimentation, or is it a > > > safe enough value? Maybe 20000ms as in other modules would have > > > been enough? > > >=20 I made experimentation on a Sierra EM9190 (SDX55) engineering sample, using a old development firmware. So, I agree that setting the same timeout of 24000ms for all modems, is not necessarily relevant. However, the current default value seems too low, in view of timeouts used on vendor-branded, then using a higher value seems relevant. Moreover, Sierra EM919x modems use a custom controller configuration, we are currently working on it. As our tests not being sufficiently conclusive, so we have not yet submitted. Best regards, Thomas > >=20 > > It was derived from testing I believe. >=20 > Following your reasoning above, shouldn't this 24000ms timeout be > applied only to the Sierra Wireless EM91xx devices (which may have > custom firmware bits delaying the initialization a bit longer), and > not to the generic SDX24, SDX55 and SDX65? >=20 > If I'm not mistaken, Thomas is testing with a custom mhi_pci_generic > entry for the EM91xx; as in > https://forum.sierrawireless.com/t/sierra-wireless-airprime-em919x-pcie-s= upport/24927 > . > I'm also playing with that same entry on my own setup, but have other > problems of my own :) >=20 >=20 > -- > Aleksander > https://aleksander.es --=20 Thomas Perrot, Bootlin Embedded Linux and kernel engineering https://bootlin.com --=-GLaBsdgJhSTUDVRwrQzr Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQGzBAABCAAdFiEEh0B3xqajCiMDqBIhn8ALBXH+Cu0FAmFVcF0ACgkQn8ALBXH+ Cu3ITgwAkPHJvqrm6FR4/p9MLmahgWI11bVVYo/FpG2G3Yi9Ft64GcUSVj7OMdpb pL5BSuWyHsCHCVowNhBVF2ZJyxmTLxI23PpUAVf94W1zApAvBXGeSaaV0ULXp6ay 1qkBQmxDRONqf1KRwfu3sHNjosBCUmZJZi+FsYV649RhW46JhdAnH+176UhmqPQF lFsHVdWMBBZ4T7yL3DAm3fo99dQy036uYlmCGOa5Utp4L51E1J0c386OLJWJUHBh ONQ8pgItLol1z4CP4fVdbVMwZ1I9FEhNfzS2rG7aET889poOSe06Jke42QK52SJh pPh6ii7qwVql4v3IAGmEFFo04qC9Wf/OU6qW9ZuT98FSEyc+ulVkFI3/G/GOgzMS nlQ4v0EtEZOyIwANn8seR+LuS5JyRehxXDaPNQZ5Z2bQGVIPgP5cSjcRmYUuauXB 4K5Y5q+qIa5A4KdKWZ6tDg9DnKXbE4A4pA0zIIVEH4XR1w9Qt7OI5P2OWOtShZQA YKE2VZKY =lA97 -----END PGP SIGNATURE----- --=-GLaBsdgJhSTUDVRwrQzr--