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 67C80E743F8 for ; Fri, 29 Sep 2023 08:37:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A256310E6CC; Fri, 29 Sep 2023 08:37:50 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTPS id CB08D10E6CC; Fri, 29 Sep 2023 08:37:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695976667; x=1727512667; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=Xz8d8GoDzs3kDhmUg2Lc1L3byZX99FHQxfjfiVY7eis=; b=TfGmJuYxDzI3NtgLKboBH6uDzhy7phKz0BHfPaGwv+4TAuc7DLS0aRFj 5DlO5PUf7KNcg4IX8W6JLodM7OrkCGkAQOXKiBWFomaIy42VWk6flOwCH F/gyvEDhMknSckKt7RM+yiExJ4w53UB4hluOaeSY//s0dnDK96rXhSI2u ndLBedU6Ejs9v1D7neOJ5sFLZml2oLrlMPln+ixlfLpE9k/O20ZXqoTUY MmI5HnlLyWfnzOCvEzZ7RpNnIGO+PdujfSVIuEPlsqbIDBh9+oI4yfWb3 pfGogmorucrB6602sUwT7G1pHRgX7LcygZYA2ULxf7gK47dqsL76/WSEW w==; X-IronPort-AV: E=McAfee;i="6600,9927,10847"; a="372611507" X-IronPort-AV: E=Sophos;i="6.03,186,1694761200"; d="scan'208";a="372611507" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2023 01:37:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10847"; a="753311224" X-IronPort-AV: E=Sophos;i="6.03,186,1694761200"; d="scan'208";a="753311224" Received: from nirmoyda-mobl.ger.corp.intel.com (HELO [10.252.39.203]) ([10.252.39.203]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Sep 2023 01:37:45 -0700 Message-ID: <7de6ddeb-0252-66a4-2c1e-8f1405b311af@linux.intel.com> Date: Fri, 29 Sep 2023 10:37:43 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 To: Nirmoy Das , intel-gfx@lists.freedesktop.org References: <20230928130015.6758-1-nirmoy.das@intel.com> Content-Language: en-US From: Nirmoy Das In-Reply-To: <20230928130015.6758-1-nirmoy.das@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: [Intel-gfx] [PATCH v7 1/4] drm/i915: Introduce intel_gt_mcr_lock_sanitize() 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: Andrzej Hajda , matthew.d.roper@intel.com, dri-devel@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Thanks reviewing this series. Merged it in  gt-next so hopefully we have bit greener CI for MTL now. Regards, Nirmoy On 9/28/2023 3:00 PM, Nirmoy Das wrote: > Implement intel_gt_mcr_lock_sanitize() to provide a mechanism > for cleaning the steer semaphore when absolutely necessary. > > v2: remove unnecessary lock(Andi, Matt) > improve the kernel doc(Matt) > s/intel_gt_mcr_lock_clear/intel_gt_mcr_lock_sanitize > > Signed-off-by: Nirmoy Das > --- > drivers/gpu/drm/i915/gt/intel_gt_mcr.c | 22 ++++++++++++++++++++++ > drivers/gpu/drm/i915/gt/intel_gt_mcr.h | 1 + > 2 files changed, 23 insertions(+) > > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_mcr.c b/drivers/gpu/drm/i915/gt/intel_gt_mcr.c > index bf4a933de03a..326c2ed1d99b 100644 > --- a/drivers/gpu/drm/i915/gt/intel_gt_mcr.c > +++ b/drivers/gpu/drm/i915/gt/intel_gt_mcr.c > @@ -419,6 +419,28 @@ void intel_gt_mcr_unlock(struct intel_gt *gt, unsigned long flags) > intel_uncore_write_fw(gt->uncore, MTL_STEER_SEMAPHORE, 0x1); > } > > +/** > + * intel_gt_mcr_lock_sanitize - Sanitize MCR steering lock > + * @gt: GT structure > + * > + * This will be used to sanitize the initial status of the hardware lock > + * during driver load and resume since there won't be any concurrent access > + * from other agents at those times, but it's possible that boot firmware > + * may have left the lock in a bad state. > + * > + */ > +void intel_gt_mcr_lock_sanitize(struct intel_gt *gt) > +{ > + /* > + * This gets called at load/resume time, so we shouldn't be > + * racing with other driver threads grabbing the mcr lock. > + */ > + lockdep_assert_not_held(>->mcr_lock); > + > + if (GRAPHICS_VER_FULL(gt->i915) >= IP_VER(12, 70)) > + intel_uncore_write_fw(gt->uncore, MTL_STEER_SEMAPHORE, 0x1); > +} > + > /** > * intel_gt_mcr_read - read a specific instance of an MCR register > * @gt: GT structure > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_mcr.h b/drivers/gpu/drm/i915/gt/intel_gt_mcr.h > index 41684495b7da..01ac565a56a4 100644 > --- a/drivers/gpu/drm/i915/gt/intel_gt_mcr.h > +++ b/drivers/gpu/drm/i915/gt/intel_gt_mcr.h > @@ -11,6 +11,7 @@ > void intel_gt_mcr_init(struct intel_gt *gt); > void intel_gt_mcr_lock(struct intel_gt *gt, unsigned long *flags); > void intel_gt_mcr_unlock(struct intel_gt *gt, unsigned long flags); > +void intel_gt_mcr_lock_sanitize(struct intel_gt *gt); > > u32 intel_gt_mcr_read(struct intel_gt *gt, > i915_mcr_reg_t reg,