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 CE849C38142 for ; Tue, 24 Jan 2023 08:55:29 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6BE3410E639; Tue, 24 Jan 2023 08:55:22 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8174010E630; Tue, 24 Jan 2023 08:55:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1674550519; x=1706086519; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=SYvybLfrGK2fw35ORWZhEgLKKSptkdp3/FLobAKi6xY=; b=BqUKFPjque29ytyapb/CmSn8sSSu6iN6XOnrf6d5yvgBfqK+/75YfpH/ dGKKLo0ou4lvGgmfejFfWuiLU/mE21MdLFES+ymb+KUqW7LMogr3alrds 56Y6QdgUrxX+9FKbCZEm5NAi2L+tq+WvfXhdCdsadsKDbnf7jbMZ0VvXH vgabA/BXiZ3LfP/qcI2mT2WjhCiVkM4yfIAhaIl1H6nWWOwIC8ilszFSk WYY/j/b1qQyy+ONfBysX5gSmhoIfsuM8EzRA7t819tO9ILl8vX2s+y07X A6KogbDTvj8oQDGIzMHJHwhNivIClIX5V9YBH2YUZjxwtYyU8Y3oWIY2F Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10599"; a="412483452" X-IronPort-AV: E=Sophos;i="5.97,242,1669104000"; d="scan'208";a="412483452" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jan 2023 00:55:18 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10599"; a="750756504" X-IronPort-AV: E=Sophos;i="5.97,241,1669104000"; d="scan'208";a="750756504" Received: from pesir-mobl.ger.corp.intel.com (HELO localhost) ([10.252.57.197]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jan 2023 00:55:15 -0800 From: Jani Nikula To: Dmitry Baryshkov , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter In-Reply-To: <20230117233905.1662645-1-dmitry.baryshkov@linaro.org> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20230117233905.1662645-1-dmitry.baryshkov@linaro.org> Date: Tue, 24 Jan 2023 10:55:12 +0200 Message-ID: <87v8kw71n3.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Intel-gfx] [PATCH v2] drm/probe_helper: sort out poll_running vs poll_enabled 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: Neil Armstrong , intel-gfx@lists.freedesktop.org, Chen-Yu Tsai , dri-devel@lists.freedesktop.org, Laurentiu Palcu , freedreno@lists.freedesktop.org, Marek Szyprowski Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Wed, 18 Jan 2023, Dmitry Baryshkov wrote: > There are two flags attemting to guard connector polling: > poll_enabled and poll_running. While poll_enabled semantics is clearly > defined and fully adhered (mark that drm_kms_helper_poll_init() was > called and not finalized by the _fini() call), the poll_running flag > doesn't have such clearliness. > > This flag is used only in drm_helper_probe_single_connector_modes() to > guard calling of drm_kms_helper_poll_enable, it doesn't guard the > drm_kms_helper_poll_fini(), etc. Change it to only be set if the polling > is actually running. Tie HPD enablement to this flag. > > This fixes the following warning reported after merging the HPD series: > > Hot plug detection already enabled > WARNING: CPU: 2 PID: 9 at drivers/gpu/drm/drm_bridge.c:1257 drm_bridge_hpd_enable+0x94/0x9c [drm] > Modules linked in: videobuf2_memops snd_soc_simple_card snd_soc_simple_card_utils fsl_imx8_ddr_perf videobuf2_common snd_soc_imx_spdif adv7511 etnaviv imx8m_ddrc imx_dcss mc cec nwl_dsi gov > CPU: 2 PID: 9 Comm: kworker/u8:0 Not tainted 6.2.0-rc2-15208-g25b283acd578 #6 > Hardware name: NXP i.MX8MQ EVK (DT) > Workqueue: events_unbound deferred_probe_work_func > pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : drm_bridge_hpd_enable+0x94/0x9c [drm] > lr : drm_bridge_hpd_enable+0x94/0x9c [drm] > sp : ffff800009ef3740 > x29: ffff800009ef3740 x28: ffff000009331f00 x27: 0000000000001000 > x26: 0000000000000020 x25: ffff800001148ed8 x24: ffff00000a8fe000 > x23: 00000000fffffffd x22: ffff000005086348 x21: ffff800001133ee0 > x20: ffff00000550d800 x19: ffff000005086288 x18: 0000000000000006 > x17: 0000000000000000 x16: ffff8000096ef008 x15: 97ffff2891004260 > x14: 2a1403e194000000 x13: 97ffff2891004260 x12: 2a1403e194000000 > x11: 7100385f29400801 x10: 0000000000000aa0 x9 : ffff800008112744 > x8 : ffff000000250b00 x7 : 0000000000000003 x6 : 0000000000000011 > x5 : 0000000000000000 x4 : ffff0000bd986a48 x3 : 0000000000000001 > x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000000250000 > Call trace: > drm_bridge_hpd_enable+0x94/0x9c [drm] > drm_bridge_connector_enable_hpd+0x2c/0x3c [drm_kms_helper] > drm_kms_helper_poll_enable+0x94/0x10c [drm_kms_helper] > drm_helper_probe_single_connector_modes+0x1a8/0x510 [drm_kms_helper] > drm_client_modeset_probe+0x204/0x1190 [drm] > __drm_fb_helper_initial_config_and_unlock+0x5c/0x4a4 [drm_kms_helper] > drm_fb_helper_initial_config+0x54/0x6c [drm_kms_helper] > drm_fbdev_client_hotplug+0xd0/0x140 [drm_kms_helper] > drm_fbdev_generic_setup+0x90/0x154 [drm_kms_helper] > dcss_kms_attach+0x1c8/0x254 [imx_dcss] > dcss_drv_platform_probe+0x90/0xfc [imx_dcss] > platform_probe+0x70/0xcc > really_probe+0xc4/0x2e0 > __driver_probe_device+0x80/0xf0 > driver_probe_device+0xe0/0x164 > __device_attach_driver+0xc0/0x13c > bus_for_each_drv+0x84/0xe0 > __device_attach+0xa4/0x1a0 > device_initial_probe+0x1c/0x30 > bus_probe_device+0xa4/0xb0 > deferred_probe_work_func+0x90/0xd0 > process_one_work+0x200/0x474 > worker_thread+0x74/0x43c > kthread+0xfc/0x110 > ret_from_fork+0x10/0x20 > ---[ end trace 0000000000000000 ]--- > > Reported-by: Laurentiu Palcu > Fixes: c8268795c9a9 ("drm/probe-helper: enable and disable HPD on connectors") > Tested-by: Marek Szyprowski > Tested-by: Chen-Yu Tsai > Signed-off-by: Dmitry Baryshkov > --- > > Changes since v1: > - Fixed drm_kms_helper_enable_hpd() to call enable_hpd() instead of > disable_hpd(). > > --- > drivers/gpu/drm/drm_probe_helper.c | 110 +++++++++++++++++------------ > 1 file changed, 63 insertions(+), 47 deletions(-) > > diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c > index 7973f2589ced..04754bb7b131 100644 > --- a/drivers/gpu/drm/drm_probe_helper.c > +++ b/drivers/gpu/drm/drm_probe_helper.c > @@ -222,6 +222,45 @@ drm_connector_mode_valid(struct drm_connector *connector, > return ret; > } > > +static void drm_kms_helper_disable_hpd(struct drm_device *dev) > +{ > + struct drm_connector *connector; > + struct drm_connector_list_iter conn_iter; > + > + drm_connector_list_iter_begin(dev, &conn_iter); > + drm_for_each_connector_iter(connector, &conn_iter) { > + const struct drm_connector_helper_funcs *funcs = > + connector->helper_private; > + > + if (funcs && funcs->disable_hpd) > + funcs->disable_hpd(connector); > + } > + drm_connector_list_iter_end(&conn_iter); > +} > + > +static bool drm_kms_helper_enable_hpd(struct drm_device *dev) > +{ > + bool poll = false; > + struct drm_connector *connector; > + struct drm_connector_list_iter conn_iter; > + > + drm_connector_list_iter_begin(dev, &conn_iter); > + drm_for_each_connector_iter(connector, &conn_iter) { > + const struct drm_connector_helper_funcs *funcs = > + connector->helper_private; > + > + if (funcs && funcs->enable_hpd) > + funcs->enable_hpd(connector); > + > + if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | > + DRM_CONNECTOR_POLL_DISCONNECT)) > + poll = true; > + } > + drm_connector_list_iter_end(&conn_iter); > + > + return poll; > +} > + > #define DRM_OUTPUT_POLL_PERIOD (10*HZ) > /** > * drm_kms_helper_poll_enable - re-enable output polling. > @@ -241,26 +280,14 @@ drm_connector_mode_valid(struct drm_connector *connector, > void drm_kms_helper_poll_enable(struct drm_device *dev) > { > bool poll = false; > - struct drm_connector *connector; > - struct drm_connector_list_iter conn_iter; > unsigned long delay = DRM_OUTPUT_POLL_PERIOD; > > - if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll) > + if (!dev->mode_config.poll_enabled || > + !drm_kms_helper_poll || > + dev->mode_config.poll_running) > return; > > - drm_connector_list_iter_begin(dev, &conn_iter); > - drm_for_each_connector_iter(connector, &conn_iter) { > - const struct drm_connector_helper_funcs *funcs = > - connector->helper_private; > - > - if (funcs && funcs->enable_hpd) > - funcs->enable_hpd(connector); > - > - if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | > - DRM_CONNECTOR_POLL_DISCONNECT)) > - poll = true; > - } > - drm_connector_list_iter_end(&conn_iter); > + poll = drm_kms_helper_enable_hpd(dev); I'd really like to see these non-functional abstractions to functions separated from the actual functional fix. There's too much going on in the same patch here. BR, Jani. > > if (dev->mode_config.delayed_event) { > /* > @@ -279,6 +306,8 @@ void drm_kms_helper_poll_enable(struct drm_device *dev) > > if (poll) > schedule_delayed_work(&dev->mode_config.output_poll_work, delay); > + > + dev->mode_config.poll_running = true; > } > EXPORT_SYMBOL(drm_kms_helper_poll_enable); > > @@ -567,10 +596,7 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, > } > > /* Re-enable polling in case the global poll config changed. */ > - if (drm_kms_helper_poll != dev->mode_config.poll_running) > - drm_kms_helper_poll_enable(dev); > - > - dev->mode_config.poll_running = drm_kms_helper_poll; > + drm_kms_helper_poll_enable(dev); > > if (connector->status == connector_status_disconnected) { > DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n", > @@ -710,8 +736,12 @@ static void output_poll_execute(struct work_struct *work) > changed = dev->mode_config.delayed_event; > dev->mode_config.delayed_event = false; > > - if (!drm_kms_helper_poll) > + if (!drm_kms_helper_poll && > + dev->mode_config.poll_running) { > + drm_kms_helper_disable_hpd(dev); > + dev->mode_config.poll_running = false; > goto out; > + } > > if (!mutex_trylock(&dev->mode_config.mutex)) { > repoll = true; > @@ -808,30 +838,6 @@ bool drm_kms_helper_is_poll_worker(void) > } > EXPORT_SYMBOL(drm_kms_helper_is_poll_worker); > > -static void drm_kms_helper_poll_disable_fini(struct drm_device *dev, bool fini) > -{ > - struct drm_connector *connector; > - struct drm_connector_list_iter conn_iter; > - > - if (!dev->mode_config.poll_enabled) > - return; > - > - if (fini) > - dev->mode_config.poll_enabled = false; > - > - drm_connector_list_iter_begin(dev, &conn_iter); > - drm_for_each_connector_iter(connector, &conn_iter) { > - const struct drm_connector_helper_funcs *funcs = > - connector->helper_private; > - > - if (funcs && funcs->disable_hpd) > - funcs->disable_hpd(connector); > - } > - drm_connector_list_iter_end(&conn_iter); > - > - cancel_delayed_work_sync(&dev->mode_config.output_poll_work); > -} > - > /** > * drm_kms_helper_poll_disable - disable output polling > * @dev: drm_device > @@ -848,7 +854,12 @@ static void drm_kms_helper_poll_disable_fini(struct drm_device *dev, bool fini) > */ > void drm_kms_helper_poll_disable(struct drm_device *dev) > { > - drm_kms_helper_poll_disable_fini(dev, false); > + if (dev->mode_config.poll_running) > + drm_kms_helper_disable_hpd(dev); > + > + cancel_delayed_work_sync(&dev->mode_config.output_poll_work); > + > + dev->mode_config.poll_running = false; > } > EXPORT_SYMBOL(drm_kms_helper_poll_disable); > > @@ -886,7 +897,12 @@ EXPORT_SYMBOL(drm_kms_helper_poll_init); > */ > void drm_kms_helper_poll_fini(struct drm_device *dev) > { > - drm_kms_helper_poll_disable_fini(dev, true); > + if (!dev->mode_config.poll_enabled) > + return; > + > + drm_kms_helper_poll_disable(dev); > + > + dev->mode_config.poll_enabled = false; > } > EXPORT_SYMBOL(drm_kms_helper_poll_fini); -- Jani Nikula, Intel Open Source Graphics Center