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 2DD39CA5FD2 for ; Thu, 1 Oct 2026 14:54:36 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CCE5B10F6CC; Thu, 1 Oct 2026 14:54:35 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="WWPnEgLV"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) by gabe.freedesktop.org (Postfix) with ESMTPS id BB1BE10F6CC for ; Thu, 1 Oct 2026 14:54:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1790866474; x=1822402474; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=GGPXe71Y8LhpSzC0yLGIheVCyoKTA9rdGqvQBoZFI+8=; b=WWPnEgLVaOaEdNGK5HZ/AY387vDTcKbTPkqX1+twrwL0SkhnMZ4b9qVw U0Ehu7YaRi8fE5yo8iqUqPCd2KwJxo3XmYokB383o4alDGtp7MqJR3vYy +MYPK34GQq7ZGjvoNhJ6UFVdeY6mun2CAEeDG6PL8TrgyX9dxGe7L2GkU WK0oaX6j17v+pQwJxIh5+aAzDT+/d6z81gQtFlKRp0MhzJuJAh6K9x8z0 SwUGqAQyOKsXFiScjPHhGy5m/cZOPsIePPIgjHisHRM/WSDEixm2bNH7m xLMObVki+gSvqfqVn2r5AQ1N2/ig36zg9QHTepk/UIMFqSOqKHvw6BzSD w==; X-CSE-ConnectionGUID: QGtebUmzTe6Jj/4XJTcX0Q== X-CSE-MsgGUID: gqZ+wo6rTNWQNmFTz9ptkA== X-IronPort-AV: E=McAfee;i="6800,10657,11922"; a="117155264" X-IronPort-AV: E=Sophos;i="6.27,134,1787036400"; d="scan'208";a="117155264" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2026 07:54:34 -0700 X-CSE-ConnectionGUID: TJjnmF7iSniirEErUQUVYg== X-CSE-MsgGUID: 11ogy7+bQm6bWum1LQuN6A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,134,1787036400"; d="scan'208";a="272436963" Received: from mkosciow-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.244.111]) by fmviesa009-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Oct 2026 07:54:32 -0700 From: Jani Nikula To: Badal Nilawar , intel-xe@lists.freedesktop.org Cc: anshuman.gupta@intel.com, rodrigo.vivi@intel.com, raag.jadav@intel.com, riana.tauro@intel.com, mallesh.koujalagi@intel.com, aravind.iddamsetty@intel.com, heikki.krogerus@linux.intel.com, himal.prasad.ghimiray@intel.com Subject: Re: [PATCH v3] drm/xe/i2c: Expose AMC Alert reason sysfs In-Reply-To: <20261001121302.4102629-2-badal.nilawar@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs Bertel Jungin Aukio 5, 02600 Espoo, Finland References: <20261001121302.4102629-2-badal.nilawar@intel.com> Date: Thu, 01 Oct 2026 17:54:29 +0300 Message-ID: <0ce399b0e0e23f168d5b916cbdcf60ad6fc058c3@intel.com> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Thu, 01 Oct 2026, Badal Nilawar wrote: > AMC raises an SMBUS alert before performing a power removal or > power-cycle operation. The xe driver then places the device into > vendor-specific wedge mode until the recovery is performed. > > Expose a read-only xe_amc_alert_reason sysfs attribute to help users > identify the required recovery action. > > Assisted-by: Claude:claude-opus-4.8 > Signed-off-by: Badal Nilawar > --- > v2: > - Created sysfs during i2c probe time > - Fix Documentation (Rodrigo) > v3: > - Keep limited information in "DOC:" section (Michal) > - Handle AMC alert none and unknown cases, document > in ABI > - Clear i2c->amc on sysfs creation failure (Sashiko) > v4: > - Fix sashiko comments > - Fix review comments (Michal) > --- > .../ABI/testing/sysfs-driver-intel-xe-amc | 24 ++++++ > drivers/gpu/drm/xe/xe_amc.c | 82 ++++++++++++++++--- > 2 files changed, 96 insertions(+), 10 deletions(-) > create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-xe-amc > > diff --git a/Documentation/ABI/testing/sysfs-driver-intel-xe-amc b/Documentation/ABI/testing/sysfs-driver-intel-xe-amc > new file mode 100644 > index 000000000000..34927fa5dcfe > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-driver-intel-xe-amc > @@ -0,0 +1,24 @@ > +What: /sys/bus/pci/drivers/xe/.../xe_amc_alert_reason > +Date: October 2026 > +KernelVersion: 7.4 > +Contact: intel-xe@lists.freedesktop.org > +Description: > + This file exposes the reason for the most recent Add-In > + Management Controller (AMC) alert on supported Intel Xe platforms. > + > + An AMC alert is delivered via an SMBUS interrupt and causes the > + device to be wedged, requiring vendor-specific recovery. > + The attribute is read-only and available to all users. > + > + Read returns a single line containing one of the following > + alert reasons: > + > + "none" > + No AMC alert has been received > + "unknown" > + AMC alert received but with unknown reason > + "firmware_download" > + "thermal_trip" > + "oob_request" > + "oob_reset" > + "catastrophic" > diff --git a/drivers/gpu/drm/xe/xe_amc.c b/drivers/gpu/drm/xe/xe_amc.c > index edd50bf8261e..7f21044fd1b7 100644 > --- a/drivers/gpu/drm/xe/xe_amc.c > +++ b/drivers/gpu/drm/xe/xe_amc.c > @@ -18,6 +18,7 @@ > #include "xe_device.h" > #include "xe_i2c.h" > #include "xe_mmio.h" > +#include "xe_printk.h" > > /** > * DOC: Add-In Management Controller (AMC) > @@ -46,16 +47,19 @@ enum xe_amc_alert { > }; > > static const char * const amc_alert[] = { > - [AMC_ALERT_FW_DOWNLOAD] = "Firmware Download", > - [AMC_ALERT_THERMAL_TRIP] = "Thermal Trip", > - [AMC_ALERT_OOB_REQUEST] = "OOB Request", > - [AMC_ALERT_OOB_RESET] = "OOB Reset", > - [AMC_ALERT_CATERR] = "Catastrophic", > + [AMC_ALERT_UNKNOWN] = "unknown", > + [AMC_ALERT_FW_DOWNLOAD] = "firmware_download", > + [AMC_ALERT_THERMAL_TRIP] = "thermal_trip", > + [AMC_ALERT_OOB_REQUEST] = "oob_request", > + [AMC_ALERT_OOB_RESET] = "oob_reset", > + [AMC_ALERT_CATERR] = "catastrophic", > }; > > struct xe_amc { > struct xe_i2c *i2c; > struct work_struct work; > + u8 alert_reason; Why u8 instead of enum xe_amc_alert? > + bool alert_seen; > }; > > struct amc_header { > @@ -104,6 +108,45 @@ static const struct amc_request amc_get_alert_reason = { > }, > }; > > +/** > + * DOC: AMC Alert Reason > + * > + * Expose AMC alert reason through device sysfs > + * > + * See Documentation/ABI/testing/sysfs-driver-intel-xe-amc for the ABI > + * specification. > + */ > + > +static ssize_t amc_alert_reason_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct xe_device *xe = pdev_to_xe_device(to_pci_dev(dev)); > + struct xe_amc *amc = xe->i2c->amc; > + u8 alert_reason; > + > + if (!amc->alert_seen) > + return sysfs_emit(buf, "none\n"); > + > + alert_reason = READ_ONCE(amc->alert_reason); > + > + return sysfs_emit(buf, "%s\n", amc_alert[alert_reason]); Please add a function for returning amc alert reason, e.g. amc_alert_reason(). You'll thank me later. > +} > +static DEVICE_ATTR_RO(amc_alert_reason); > + > +static void amc_remove_alert_sysfs(struct xe_i2c *i2c) > +{ > + struct device *dev = i2c->drm_dev; > + > + device_remove_file(dev, &dev_attr_amc_alert_reason); > +} > + > +static int amc_create_alert_sysfs(struct xe_i2c *i2c) > +{ > + struct device *dev = i2c->drm_dev; > + > + return device_create_file(dev, &dev_attr_amc_alert_reason); > +} > + > static void xe_amc_work(struct work_struct *work) > { > const struct amc_request *request = &amc_get_alert_reason; > @@ -153,17 +196,26 @@ static void xe_amc_work(struct work_struct *work) > out_reassert_interrupt: > xe_mmio_rmw32(amc->i2c->mmio, I2C_CONFIG_CMD, PCI_COMMAND_INTX_DISABLE, 0); > > + amc->alert_seen = true; > + > switch (alert_reason) { > case AMC_ALERT_FW_DOWNLOAD: > case AMC_ALERT_THERMAL_TRIP: > case AMC_ALERT_OOB_REQUEST: > case AMC_ALERT_OOB_RESET: > - case AMC_ALERT_CATERR: > - dev_warn(amc->i2c->drm_dev, "AMC Alert: %s\n", amc_alert[alert_reason]); > - xe_device_declare_wedged(i2c_client_to_xe_device(client)); > + case AMC_ALERT_CATERR: { > + struct xe_device *xe = i2c_client_to_xe_device(client); > + > + WRITE_ONCE(amc->alert_reason, alert_reason); > + dev_warn(amc->i2c->drm_dev, > + "AMC Alert: %s (%u)\n", amc_alert[alert_reason], alert_reason); > + xe_device_set_wedged_method(xe, DRM_WEDGE_RECOVERY_VENDOR); > + xe_device_declare_wedged(xe); > break; > + } > default: > - dev_warn(amc->i2c->drm_dev, "unknown AMC alert: %d\n", alert_reason); > + WRITE_ONCE(amc->alert_reason, AMC_ALERT_UNKNOWN); > + dev_warn(amc->i2c->drm_dev, "AMC Alert: unknown (%u)\n", alert_reason); > break; > } > } > @@ -176,6 +228,7 @@ void xe_amc_handle_alert(struct xe_i2c *i2c) > int xe_amc_init(struct xe_i2c *i2c) > { > struct xe_amc *amc; > + int ret; > > amc = kzalloc_obj(*amc); > if (!amc) > @@ -185,13 +238,22 @@ int xe_amc_init(struct xe_i2c *i2c) > i2c->amc = amc; > amc->i2c = i2c; > > - return 0; > + amc->alert_seen = false; > + ret = amc_create_alert_sysfs(i2c); > + if (ret) { > + kfree(i2c->amc); > + i2c->amc = NULL; > + } > + > + return ret; > } > > void xe_amc_exit(struct xe_i2c *i2c) > { > if (i2c->amc) { > + amc_remove_alert_sysfs(i2c); > cancel_work_sync(&i2c->amc->work); > kfree(i2c->amc); > + i2c->amc = NULL; > } > } -- Jani Nikula, Intel