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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53E3BC282C8 for ; Mon, 28 Jan 2019 09:30:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C57820880 for ; Mon, 28 Jan 2019 09:30:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726627AbfA1Jai convert rfc822-to-8bit (ORCPT ); Mon, 28 Jan 2019 04:30:38 -0500 Received: from mga06.intel.com ([134.134.136.31]:2844 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726369AbfA1Jai (ORCPT ); Mon, 28 Jan 2019 04:30:38 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 Jan 2019 01:30:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,533,1539673200"; d="scan'208";a="139362894" Received: from irsmsx104.ger.corp.intel.com ([163.33.3.159]) by fmsmga004.fm.intel.com with ESMTP; 28 Jan 2019 01:30:36 -0800 Received: from irsmsx102.ger.corp.intel.com ([169.254.2.65]) by IRSMSX104.ger.corp.intel.com ([169.254.5.101]) with mapi id 14.03.0415.000; Mon, 28 Jan 2019 09:30:35 +0000 From: "Kahola, Mika" To: "ville.syrjala@linux.intel.com" , "intel-gfx@lists.freedesktop.org" CC: "dkk089@gmail.com" , "stable@vger.kernel.org" Subject: Re: [Intel-gfx] [PATCH v2] drm/i915: Try to sanitize bogus DPLL state left over by broken SNB BIOSen Thread-Topic: [Intel-gfx] [PATCH v2] drm/i915: Try to sanitize bogus DPLL state left over by broken SNB BIOSen Thread-Index: AQHUqdYUc1W0dm1r/UKcWlUR5cNgIqXEhPwA Date: Mon, 28 Jan 2019 09:30:35 +0000 Message-ID: References: <20190109120919.21668-1-ville.syrjala@linux.intel.com> <20190111174950.10681-1-ville.syrjala@linux.intel.com> In-Reply-To: <20190111174950.10681-1-ville.syrjala@linux.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.237.72.207] Content-Type: text/plain; charset="iso-8859-15" Content-ID: Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch look ok to me. On Fri, 2019-01-11 at 19:49 +0200, Ville Syrjala wrote: > From: Ville Syrjälä > > Certain SNB machines (eg. ASUS K53SV) seem to have a broken BIOS > which misprograms the hardware badly when encountering a suitably > high resolution display. The programmed pipe timings are somewhat > bonkers and the DPLL is totally misprogrammed (P divider == 0). > That will result in atomic commit timeouts as apparently the pipe > is sufficiently stuck to not signal vblank interrupts. > > IIRC something like this was also observed on some other SNB > machine years ago (might have been a Dell XPS 8300) but a BIOS > update cured it. Sadly looks like this was never fixed for the > ASUS K53SV as the latest BIOS (K53SV.320 11/11/2011) is still > broken. > > The quickest way to deal with this seems to be to shut down > the pipe+ports+DPLL. Unfortunately doing this during the > normal sanitization phase isn't quite soon enough as we > already spew several WARNs about the bogus hardware state. > But it's better than hanging the boot for a few dozen seconds. > Since this is limited to a few old machines it doesn't seem > entirely worthwile to try and rework the readout+sanitization > code to handle it more gracefully. > > v2: Fix potential NULL deref (kbuild test robot) > Constify has_bogus_dpll_config() > > Cc: stable@vger.kernel.org # v4.20+ > Cc: Daniel Kamil Kozar > Reported-by: Daniel Kamil Kozar > Tested-by: Daniel Kamil Kozar > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109245 > Fixes: 516a49cc1946 ("drm/i915: Fix assert_plane() warning on bootup > with external display") Reviewed-by: Mika Kahola > Signed-off-by: Ville Syrjälä > --- > drivers/gpu/drm/i915/intel_display.c | 50 ++++++++++++++++++++++++ > ---- > 1 file changed, 44 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_display.c > b/drivers/gpu/drm/i915/intel_display.c > index 5dc0de89c49e..6cd6048b4731 100644 > --- a/drivers/gpu/drm/i915/intel_display.c > +++ b/drivers/gpu/drm/i915/intel_display.c > @@ -15438,16 +15438,45 @@ static void intel_sanitize_crtc(struct > intel_crtc *crtc, > } > } > > +static bool has_bogus_dpll_config(const struct intel_crtc_state > *crtc_state) > +{ > + struct drm_i915_private *dev_priv = to_i915(crtc_state- > >base.crtc->dev); > + > + /* > + * Some SNB BIOSen (eg. ASUS K53SV) are known to misprogram > + * the hardware when a high res displays plugged in. DPLL P > + * divider is zero, and the pipe timings are bonkers. We'll > + * try to disable everything in that case. > + * > + * FIXME would be nice to be able to sanitize this state > + * without several WARNs, but for now let's take the easy > + * road. > + */ > + return IS_GEN(dev_priv, 6) && > + crtc_state->base.active && > + crtc_state->shared_dpll && > + crtc_state->port_clock == 0; > +} > + > static void intel_sanitize_encoder(struct intel_encoder *encoder) > { > struct drm_i915_private *dev_priv = to_i915(encoder->base.dev); > struct intel_connector *connector; > + struct intel_crtc *crtc = to_intel_crtc(encoder->base.crtc); > + struct intel_crtc_state *crtc_state = crtc ? > + to_intel_crtc_state(crtc->base.state) : NULL; > > /* We need to check both for a crtc link (meaning that the > * encoder is active and trying to read from a pipe) and the > * pipe itself being active. */ > - bool has_active_crtc = encoder->base.crtc && > - to_intel_crtc(encoder->base.crtc)->active; > + bool has_active_crtc = crtc_state && > + crtc_state->base.active; > + > + if (crtc_state && has_bogus_dpll_config(crtc_state)) { > + DRM_DEBUG_KMS("BIOS has misprogrammed the hardware. > Disabling pipe %c\n", > + pipe_name(crtc->pipe)); > + has_active_crtc = false; > + } > > connector = intel_encoder_find_connector(encoder); > if (connector && !has_active_crtc) { > @@ -15458,16 +15487,25 @@ static void intel_sanitize_encoder(struct > intel_encoder *encoder) > /* Connector is active, but has no active pipe. This is > * fallout from our resume register restoring. Disable > * the encoder manually again. */ > - if (encoder->base.crtc) { > - struct drm_crtc_state *crtc_state = encoder- > >base.crtc->state; > + if (crtc_state) { > + struct drm_encoder *best_encoder; > > DRM_DEBUG_KMS("[ENCODER:%d:%s] manually > disabled\n", > encoder->base.base.id, > encoder->base.name); > + > + /* avoid oopsing in case the hooks consult > best_encoder */ > + best_encoder = connector->base.state- > >best_encoder; > + connector->base.state->best_encoder = &encoder- > >base; > + > if (encoder->disable) > - encoder->disable(encoder, > to_intel_crtc_state(crtc_state), connector->base.state); > + encoder->disable(encoder, crtc_state, > + connector- > >base.state); > if (encoder->post_disable) > - encoder->post_disable(encoder, > to_intel_crtc_state(crtc_state), connector->base.state); > + encoder->post_disable(encoder, > crtc_state, > + connector- > >base.state); > + > + connector->base.state->best_encoder = > best_encoder; > } > encoder->base.crtc = NULL; >