From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.domeneshop.no (smtp.domeneshop.no [194.63.252.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D1995CA6 for ; Wed, 7 Sep 2022 16:49:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tronnes.org ; s=ds202112; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=9N6URuex089GHLCqcq5OwqFtSiBdOniUj0H5n1oTE7U=; b=CJU1sQi7bpE3/vdL5WN6zgzECp HHbmXjaIPD3FMzb3sar3e+/e26bryRNwv1KdQp0IoqozvMQr2DTCs0jssE29RdyuEJv/rK8lX2WJK w2o8NMpLEUrJk30eOPVkwTn6wxVW0kBbnnB7MtXliQTOvmqSHodwkDV+uwCs5gbOmF0eJBvZUDQ2z e2JcgdbF+68jArc56Os1nj6UK+Y6uy14uY/Jul33K5WJlLdVPkusBSWmxB8/5J+Jivi1yAAY2SqaJ uYShCgxeLJVticyfntOzrgiAdo8jbBv692avVuEnjNwP7CDEGvsUfDGMPAMFYNmIHjp8I7qWEiYf6 MKMfxSqg==; Received: from [2a01:799:961:d200:cca0:57ac:c55d:a485] (port=53589) by smtp.domeneshop.no with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oVyAf-0000KB-VO; Wed, 07 Sep 2022 18:45:01 +0200 Message-ID: Date: Wed, 7 Sep 2022 18:44:53 +0200 Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.0 Subject: Re: [PATCH v2 00/41] drm: Analog TV Improvements To: Stefan Wahren , Maxime Ripard Cc: Ben Skeggs , David Airlie , Chen-Yu Tsai , Thomas Zimmermann , Jani Nikula , Lyude Paul , Philipp Zabel , Maarten Lankhorst , Rodrigo Vivi , Tvrtko Ursulin , Jernej Skrabec , Samuel Holland , Karol Herbst , Emma Anholt , Daniel Vetter , Joonas Lahtinen , Dom Cobley , Hans de Goede , linux-arm-kernel@lists.infradead.org, Phil Elwell , intel-gfx@lists.freedesktop.org, Dave Stevenson , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org, linux-sunxi@lists.linux.dev, Mateusz Kwiatkowski , Geert Uytterhoeven , =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <24e09a29-6d04-3b1e-63ce-cd3c31d350e2@tronnes.org> <020d44e6-884b-a817-8265-3461638cac71@tronnes.org> <20220905145729.ln675jko3aw6sgzs@houat> <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> From: =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= In-Reply-To: <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Den 07.09.2022 12.36, skrev Stefan Wahren: > Hi Maxime, > > Am 05.09.22 um 16:57 schrieb Maxime Ripard: >> On Fri, Sep 02, 2022 at 01:28:16PM +0200, Noralf Trønnes wrote: >>> >>> Den 01.09.2022 21.35, skrev Noralf Trønnes: >>>> >>>> I have finally found a workaround for my kernel hangs. >>>> >>>> Dom had a look at my kernel and found that the VideoCore was fine, and >>>> he said this: >>>> >>>>> That suggests cause of lockup was on arm side rather than VC side. >>>>> >>>>> But it's hard to diagnose further. Once you've had a peripheral not >>>>> respond, the AXI bus locks up and no further operations are possible. >>>>> Usual causes of this are required clocks being stopped or domains >>>>> disabled and then trying to access the hardware. >>>>> >>>> So when I got this on my 64-bit build: >>>> >>>> [  166.702171] SError Interrupt on CPU1, code 0x00000000bf000002 -- >>>> SError >>>> [  166.702187] CPU: 1 PID: 8 Comm: kworker/u8:0 Tainted: G        W >>>>      5.19.0-rc6-00096-gba7973977976-dirty #1 >>>> [  166.702200] Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) >>>> [  166.702206] Workqueue: events_freezable_power_ >>>> thermal_zone_device_check >>>> [  166.702231] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS >>>> BTYPE=--) >>>> [  166.702242] pc : regmap_mmio_read32le+0x10/0x28 >>>> [  166.702261] lr : regmap_mmio_read+0x44/0x70 >>>> ... >>>> [  166.702606]  bcm2711_get_temp+0x58/0xb0 [bcm2711_thermal] >>>> >>>> I wondered if that reg read was stalled due to a clock being stopped. >>>> >>>> Lo and behold, disabling runtime pm and keeping the vec clock running >>>> all the time fixed it[1]. >>>> >>>> I don't know what the problem is, but at least I can now test this >>>> patchset. >>>> >>>> [1] https://gist.github.com/notro/23b984e7fa05cfbda2db50a421cac065 >>>> >>> It turns out I didn't have to disable runtime pm: >>> https://gist.github.com/notro/0adcfcb12460b54e54458afe11dc8ea2 >> If the bcm2711_thermal IP needs that clock to be enabled, it should grab >> a reference itself, but it looks like even the device tree binding >> doesn't ask for one. > The missing clock in the device tree binding is expected, because > despite of the code there is not much information about the BCM2711 > clock tree. But i'm skeptical that the AVS IP actually needs the VEC > clock, i think it's more likely that the VEC clock parent is changed and > that cause this issue. I could take care of the bcm2711 binding & driver > if i know which clock is really necessary. Seems you're right, keeping the parent always enabled is enough: clk_prepare_enable(clk_get_parent(vec->clock)); // pllc_per I tried enabling just the grandparent clock as well, but that didn't help. Without the clock hack it seems the hang occurs when switching between NTSC and PAL, at most I've been able to do that 4-5 times before it hangs. For a while it looked like fbdev/fbcon had a play in this, but then I realised that it just gave me a NTSC mode to start from and to go back to when qutting modetest. Noralf. 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 23C3AC54EE9 for ; Wed, 7 Sep 2022 16:45:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E5BB710E7D3; Wed, 7 Sep 2022 16:45:11 +0000 (UTC) Received: from smtp.domeneshop.no (smtp.domeneshop.no [IPv6:2a01:5b40:0:3005::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 11E8A10E7D3; Wed, 7 Sep 2022 16:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tronnes.org ; s=ds202112; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=9N6URuex089GHLCqcq5OwqFtSiBdOniUj0H5n1oTE7U=; b=CJU1sQi7bpE3/vdL5WN6zgzECp HHbmXjaIPD3FMzb3sar3e+/e26bryRNwv1KdQp0IoqozvMQr2DTCs0jssE29RdyuEJv/rK8lX2WJK w2o8NMpLEUrJk30eOPVkwTn6wxVW0kBbnnB7MtXliQTOvmqSHodwkDV+uwCs5gbOmF0eJBvZUDQ2z e2JcgdbF+68jArc56Os1nj6UK+Y6uy14uY/Jul33K5WJlLdVPkusBSWmxB8/5J+Jivi1yAAY2SqaJ uYShCgxeLJVticyfntOzrgiAdo8jbBv692avVuEnjNwP7CDEGvsUfDGMPAMFYNmIHjp8I7qWEiYf6 MKMfxSqg==; Received: from [2a01:799:961:d200:cca0:57ac:c55d:a485] (port=53589) by smtp.domeneshop.no with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oVyAf-0000KB-VO; Wed, 07 Sep 2022 18:45:01 +0200 Message-ID: Date: Wed, 7 Sep 2022 18:44:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.0 To: Stefan Wahren , Maxime Ripard References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <24e09a29-6d04-3b1e-63ce-cd3c31d350e2@tronnes.org> <020d44e6-884b-a817-8265-3461638cac71@tronnes.org> <20220905145729.ln675jko3aw6sgzs@houat> <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> From: =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= In-Reply-To: <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [Nouveau] [PATCH v2 00/41] drm: Analog TV Improvements X-BeenThere: nouveau@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Nouveau development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , nouveau@lists.freedesktop.org, Joonas Lahtinen , dri-devel@lists.freedesktop.org, Phil Elwell , Emma Anholt , Samuel Holland , Jernej Skrabec , Chen-Yu Tsai , Geert Uytterhoeven , Ben Skeggs , linux-sunxi@lists.linux.dev, intel-gfx@lists.freedesktop.org, Maarten Lankhorst , Jani Nikula , Hans de Goede , Rodrigo Vivi , Daniel Vetter , linux-arm-kernel@lists.infradead.org, Tvrtko Ursulin , Dom Cobley , linux-kernel@vger.kernel.org, Mateusz Kwiatkowski , =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= , Philipp Zabel Errors-To: nouveau-bounces@lists.freedesktop.org Sender: "Nouveau" Den 07.09.2022 12.36, skrev Stefan Wahren: > Hi Maxime, > > Am 05.09.22 um 16:57 schrieb Maxime Ripard: >> On Fri, Sep 02, 2022 at 01:28:16PM +0200, Noralf Trønnes wrote: >>> >>> Den 01.09.2022 21.35, skrev Noralf Trønnes: >>>> >>>> I have finally found a workaround for my kernel hangs. >>>> >>>> Dom had a look at my kernel and found that the VideoCore was fine, and >>>> he said this: >>>> >>>>> That suggests cause of lockup was on arm side rather than VC side. >>>>> >>>>> But it's hard to diagnose further. Once you've had a peripheral not >>>>> respond, the AXI bus locks up and no further operations are possible. >>>>> Usual causes of this are required clocks being stopped or domains >>>>> disabled and then trying to access the hardware. >>>>> >>>> So when I got this on my 64-bit build: >>>> >>>> [  166.702171] SError Interrupt on CPU1, code 0x00000000bf000002 -- >>>> SError >>>> [  166.702187] CPU: 1 PID: 8 Comm: kworker/u8:0 Tainted: G        W >>>>      5.19.0-rc6-00096-gba7973977976-dirty #1 >>>> [  166.702200] Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) >>>> [  166.702206] Workqueue: events_freezable_power_ >>>> thermal_zone_device_check >>>> [  166.702231] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS >>>> BTYPE=--) >>>> [  166.702242] pc : regmap_mmio_read32le+0x10/0x28 >>>> [  166.702261] lr : regmap_mmio_read+0x44/0x70 >>>> ... >>>> [  166.702606]  bcm2711_get_temp+0x58/0xb0 [bcm2711_thermal] >>>> >>>> I wondered if that reg read was stalled due to a clock being stopped. >>>> >>>> Lo and behold, disabling runtime pm and keeping the vec clock running >>>> all the time fixed it[1]. >>>> >>>> I don't know what the problem is, but at least I can now test this >>>> patchset. >>>> >>>> [1] https://gist.github.com/notro/23b984e7fa05cfbda2db50a421cac065 >>>> >>> It turns out I didn't have to disable runtime pm: >>> https://gist.github.com/notro/0adcfcb12460b54e54458afe11dc8ea2 >> If the bcm2711_thermal IP needs that clock to be enabled, it should grab >> a reference itself, but it looks like even the device tree binding >> doesn't ask for one. > The missing clock in the device tree binding is expected, because > despite of the code there is not much information about the BCM2711 > clock tree. But i'm skeptical that the AVS IP actually needs the VEC > clock, i think it's more likely that the VEC clock parent is changed and > that cause this issue. I could take care of the bcm2711 binding & driver > if i know which clock is really necessary. Seems you're right, keeping the parent always enabled is enough: clk_prepare_enable(clk_get_parent(vec->clock)); // pllc_per I tried enabling just the grandparent clock as well, but that didn't help. Without the clock hack it seems the hang occurs when switching between NTSC and PAL, at most I've been able to do that 4-5 times before it hangs. For a while it looked like fbdev/fbcon had a play in this, but then I realised that it just gave me a NTSC mode to start from and to go back to when qutting modetest. Noralf. 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3287AC38145 for ; Wed, 7 Sep 2022 16:45:18 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 50A3A10E7DC; Wed, 7 Sep 2022 16:45:13 +0000 (UTC) Received: from smtp.domeneshop.no (smtp.domeneshop.no [IPv6:2a01:5b40:0:3005::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id 11E8A10E7D3; Wed, 7 Sep 2022 16:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tronnes.org ; s=ds202112; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:From: References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=9N6URuex089GHLCqcq5OwqFtSiBdOniUj0H5n1oTE7U=; b=CJU1sQi7bpE3/vdL5WN6zgzECp HHbmXjaIPD3FMzb3sar3e+/e26bryRNwv1KdQp0IoqozvMQr2DTCs0jssE29RdyuEJv/rK8lX2WJK w2o8NMpLEUrJk30eOPVkwTn6wxVW0kBbnnB7MtXliQTOvmqSHodwkDV+uwCs5gbOmF0eJBvZUDQ2z e2JcgdbF+68jArc56Os1nj6UK+Y6uy14uY/Jul33K5WJlLdVPkusBSWmxB8/5J+Jivi1yAAY2SqaJ uYShCgxeLJVticyfntOzrgiAdo8jbBv692avVuEnjNwP7CDEGvsUfDGMPAMFYNmIHjp8I7qWEiYf6 MKMfxSqg==; Received: from [2a01:799:961:d200:cca0:57ac:c55d:a485] (port=53589) by smtp.domeneshop.no with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oVyAf-0000KB-VO; Wed, 07 Sep 2022 18:45:01 +0200 Message-ID: Date: Wed, 7 Sep 2022 18:44:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.0 Subject: Re: [PATCH v2 00/41] drm: Analog TV Improvements To: Stefan Wahren , Maxime Ripard References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <24e09a29-6d04-3b1e-63ce-cd3c31d350e2@tronnes.org> <020d44e6-884b-a817-8265-3461638cac71@tronnes.org> <20220905145729.ln675jko3aw6sgzs@houat> <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> From: =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= In-Reply-To: <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Karol Herbst , David Airlie , nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Phil Elwell , Emma Anholt , Samuel Holland , Jernej Skrabec , Chen-Yu Tsai , Geert Uytterhoeven , Ben Skeggs , linux-sunxi@lists.linux.dev, Thomas Zimmermann , intel-gfx@lists.freedesktop.org, Hans de Goede , Rodrigo Vivi , linux-arm-kernel@lists.infradead.org, Tvrtko Ursulin , Dom Cobley , Dave Stevenson , linux-kernel@vger.kernel.org, Mateusz Kwiatkowski , =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Den 07.09.2022 12.36, skrev Stefan Wahren: > Hi Maxime, > > Am 05.09.22 um 16:57 schrieb Maxime Ripard: >> On Fri, Sep 02, 2022 at 01:28:16PM +0200, Noralf Trønnes wrote: >>> >>> Den 01.09.2022 21.35, skrev Noralf Trønnes: >>>> >>>> I have finally found a workaround for my kernel hangs. >>>> >>>> Dom had a look at my kernel and found that the VideoCore was fine, and >>>> he said this: >>>> >>>>> That suggests cause of lockup was on arm side rather than VC side. >>>>> >>>>> But it's hard to diagnose further. Once you've had a peripheral not >>>>> respond, the AXI bus locks up and no further operations are possible. >>>>> Usual causes of this are required clocks being stopped or domains >>>>> disabled and then trying to access the hardware. >>>>> >>>> So when I got this on my 64-bit build: >>>> >>>> [  166.702171] SError Interrupt on CPU1, code 0x00000000bf000002 -- >>>> SError >>>> [  166.702187] CPU: 1 PID: 8 Comm: kworker/u8:0 Tainted: G        W >>>>      5.19.0-rc6-00096-gba7973977976-dirty #1 >>>> [  166.702200] Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) >>>> [  166.702206] Workqueue: events_freezable_power_ >>>> thermal_zone_device_check >>>> [  166.702231] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS >>>> BTYPE=--) >>>> [  166.702242] pc : regmap_mmio_read32le+0x10/0x28 >>>> [  166.702261] lr : regmap_mmio_read+0x44/0x70 >>>> ... >>>> [  166.702606]  bcm2711_get_temp+0x58/0xb0 [bcm2711_thermal] >>>> >>>> I wondered if that reg read was stalled due to a clock being stopped. >>>> >>>> Lo and behold, disabling runtime pm and keeping the vec clock running >>>> all the time fixed it[1]. >>>> >>>> I don't know what the problem is, but at least I can now test this >>>> patchset. >>>> >>>> [1] https://gist.github.com/notro/23b984e7fa05cfbda2db50a421cac065 >>>> >>> It turns out I didn't have to disable runtime pm: >>> https://gist.github.com/notro/0adcfcb12460b54e54458afe11dc8ea2 >> If the bcm2711_thermal IP needs that clock to be enabled, it should grab >> a reference itself, but it looks like even the device tree binding >> doesn't ask for one. > The missing clock in the device tree binding is expected, because > despite of the code there is not much information about the BCM2711 > clock tree. But i'm skeptical that the AVS IP actually needs the VEC > clock, i think it's more likely that the VEC clock parent is changed and > that cause this issue. I could take care of the bcm2711 binding & driver > if i know which clock is really necessary. Seems you're right, keeping the parent always enabled is enough: clk_prepare_enable(clk_get_parent(vec->clock)); // pllc_per I tried enabling just the grandparent clock as well, but that didn't help. Without the clock hack it seems the hang occurs when switching between NTSC and PAL, at most I've been able to do that 4-5 times before it hangs. For a while it looked like fbdev/fbcon had a play in this, but then I realised that it just gave me a NTSC mode to start from and to go back to when qutting modetest. Noralf. 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0495EC54EE9 for ; Wed, 7 Sep 2022 16:46:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=maU29MykWTyKwIDmNjYGjUBLZe9UoXP+ji0EYl/zjDk=; b=x/6wUc0YLCqAJQ XpVh7UjugluorveRz0+TNMErNRK6eciBnkLpzQN06IpF1+PHAaEFQNF2iIz7exdbzj+etUpK9WX/1 TrZXwhjDSc0/UNyK/Izh332dcyHoV5BrGzx8qEr9is1H46qUjJn8Ws8xEDHd95qyELdihdYtxrY9Z v59vCVXJTbYr9x0+8uwMvmf0zFH21KtprAOfkU1qW5CrV/XewbTDBkY9npBzyFtefzP1uSNXCETwM cLwY1Ha6XNxwWTv5iXyz6x/wp+dHHYAf2M4+Hg6VGGRIdL+5yt0P4UcSX/urwJDKrq2pokz5x0vRw WH3r5WOjiHLmPF9G4CZQ==; 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Received: from [2a01:799:961:d200:cca0:57ac:c55d:a485] (port=53589) by smtp.domeneshop.no with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oVyAf-0000KB-VO; Wed, 07 Sep 2022 18:45:01 +0200 Message-ID: Date: Wed, 7 Sep 2022 18:44:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.0 To: Stefan Wahren , Maxime Ripard References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <24e09a29-6d04-3b1e-63ce-cd3c31d350e2@tronnes.org> <020d44e6-884b-a817-8265-3461638cac71@tronnes.org> <20220905145729.ln675jko3aw6sgzs@houat> <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> From: =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= In-Reply-To: <965de5c0-bc6a-7210-c946-b916ae2219fc@i2se.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Mailman-Approved-At: Mon, 12 Sep 2022 13:38:08 +0000 Subject: Re: [Intel-gfx] [PATCH v2 00/41] drm: Analog TV Improvements X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Karol Herbst , David Airlie , nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Phil Elwell , Emma Anholt , Samuel Holland , Jernej Skrabec , Chen-Yu Tsai , Geert Uytterhoeven , Ben Skeggs , linux-sunxi@lists.linux.dev, Thomas Zimmermann , intel-gfx@lists.freedesktop.org, Rodrigo Vivi , Daniel Vetter , linux-arm-kernel@lists.infradead.org, Dom Cobley , Dave Stevenson , linux-kernel@vger.kernel.org, Mateusz Kwiatkowski , =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= , Philipp Zabel Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Den 07.09.2022 12.36, skrev Stefan Wahren: > Hi Maxime, > > Am 05.09.22 um 16:57 schrieb Maxime Ripard: >> On Fri, Sep 02, 2022 at 01:28:16PM +0200, Noralf Trønnes wrote: >>> >>> Den 01.09.2022 21.35, skrev Noralf Trønnes: >>>> >>>> I have finally found a workaround for my kernel hangs. >>>> >>>> Dom had a look at my kernel and found that the VideoCore was fine, and >>>> he said this: >>>> >>>>> That suggests cause of lockup was on arm side rather than VC side. >>>>> >>>>> But it's hard to diagnose further. Once you've had a peripheral not >>>>> respond, the AXI bus locks up and no further operations are possible. >>>>> Usual causes of this are required clocks being stopped or domains >>>>> disabled and then trying to access the hardware. >>>>> >>>> So when I got this on my 64-bit build: >>>> >>>> [  166.702171] SError Interrupt on CPU1, code 0x00000000bf000002 -- >>>> SError >>>> [  166.702187] CPU: 1 PID: 8 Comm: kworker/u8:0 Tainted: G        W >>>>      5.19.0-rc6-00096-gba7973977976-dirty #1 >>>> [  166.702200] Hardware name: Raspberry Pi 4 Model B Rev 1.1 (DT) >>>> [  166.702206] Workqueue: events_freezable_power_ >>>> thermal_zone_device_check >>>> [  166.702231] pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS >>>> BTYPE=--) >>>> [  166.702242] pc : regmap_mmio_read32le+0x10/0x28 >>>> [  166.702261] lr : regmap_mmio_read+0x44/0x70 >>>> ... >>>> [  166.702606]  bcm2711_get_temp+0x58/0xb0 [bcm2711_thermal] >>>> >>>> I wondered if that reg read was stalled due to a clock being stopped. >>>> >>>> Lo and behold, disabling runtime pm and keeping the vec clock running >>>> all the time fixed it[1]. >>>> >>>> I don't know what the problem is, but at least I can now test this >>>> patchset. >>>> >>>> [1] https://gist.github.com/notro/23b984e7fa05cfbda2db50a421cac065 >>>> >>> It turns out I didn't have to disable runtime pm: >>> https://gist.github.com/notro/0adcfcb12460b54e54458afe11dc8ea2 >> If the bcm2711_thermal IP needs that clock to be enabled, it should grab >> a reference itself, but it looks like even the device tree binding >> doesn't ask for one. > The missing clock in the device tree binding is expected, because > despite of the code there is not much information about the BCM2711 > clock tree. But i'm skeptical that the AVS IP actually needs the VEC > clock, i think it's more likely that the VEC clock parent is changed and > that cause this issue. I could take care of the bcm2711 binding & driver > if i know which clock is really necessary. Seems you're right, keeping the parent always enabled is enough: clk_prepare_enable(clk_get_parent(vec->clock)); // pllc_per I tried enabling just the grandparent clock as well, but that didn't help. Without the clock hack it seems the hang occurs when switching between NTSC and PAL, at most I've been able to do that 4-5 times before it hangs. For a while it looked like fbdev/fbcon had a play in this, but then I realised that it just gave me a NTSC mode to start from and to go back to when qutting modetest. Noralf.