From patchwork Mon Mar 24 13:29:51 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andi Shyti X-Patchwork-Id: 14027335 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 09A9EC36002 for ; Mon, 24 Mar 2025 13:32:03 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 71F2210E40E; Mon, 24 Mar 2025 13:32:02 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="lLpDr9p6"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7FD8D10E40E; Mon, 24 Mar 2025 13:32:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1742823122; x=1774359122; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=92l6FArlYG7KWJ7HEUNaMMrZ2E5B106tBpHBnZs79uU=; b=lLpDr9p6FNHczF1v0BlGzW9DlbTPYwGuo5oR2C5gaEFyt5CXXV0kEs3o E/MQuCXEkJnEC2X8f1N2V6kbiHgb84MfupKPypIDDGJS/QWu+On04uSJR bkUxN+cmWHpA2GDjHOFGEZyJEE//IIyisXSLHA5sgijunDfkYf1zMUaLc uEHP9v6Hzzwr1eOpnFD3RqFkV8FEiwamQgsEE3z4rjnZ6TBntKagaCg5E DNmUwnLk+x24V3GJcMS8rQsSecokIQHcViEPLS+fx77W6EGuwZyijr4en gCnrL6Hj3Fypx6so08IrXf74o9GdVv6svifizyrP0Svk654BGwTMCMR3E w==; X-CSE-ConnectionGUID: 93+RGvJKSiin4YeDmLn+Hg== X-CSE-MsgGUID: MXog9HOARhqghltVHZG6hQ== X-IronPort-AV: E=McAfee;i="6700,10204,11383"; a="66493475" X-IronPort-AV: E=Sophos;i="6.14,272,1736841600"; d="scan'208";a="66493475" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2025 06:32:01 -0700 X-CSE-ConnectionGUID: D0UQ/YLqSCuLac1K6jBGEQ== X-CSE-MsgGUID: Jfb1NZdxRvWy1VN2i7580A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.14,272,1736841600"; d="scan'208";a="123847292" Received: from slindbla-desk.ger.corp.intel.com (HELO localhost) ([10.245.246.252]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2025 06:31:57 -0700 From: Andi Shyti To: intel-gfx , dri-devel Cc: Tvrtko Ursulin , Joonas Lahtinen , Chris Wilson , Simona Vetter , Arshad Mehmood , Michal Mrozek , Andi Shyti , Andi Shyti Subject: [PATCH v4 15/15] drm/i915/gt: Allow the user to change the CCS mode through sysfs Date: Mon, 24 Mar 2025 14:29:51 +0100 Message-ID: <20250324132952.1075209-16-andi.shyti@linux.intel.com> X-Mailer: git-send-email 2.47.2 In-Reply-To: <20250324132952.1075209-1-andi.shyti@linux.intel.com> References: <20250324132952.1075209-1-andi.shyti@linux.intel.com> MIME-Version: 1.0 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Create the 'ccs_mode' file under /sys/class/drm/cardX/gt/gt0/ccs_mode This file allows the user to read and set the current CCS mode. - Reading: The user can read the current CCS mode, which can be 1, 2, or 4. This value is derived from the current engine mask. - Writing: The user can set the CCS mode to 1, 2, or 4, depending on the desired number of exposed engines and the required load balancing. The interface will return -EBUSY if other clients are connected to i915, or -EINVAL if an invalid value is set. Signed-off-by: Andi Shyti --- drivers/gpu/drm/i915/gt/intel_gt_ccs_mode.c | 82 ++++++++++++++++++++- 1 file changed, 80 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_gt_ccs_mode.c b/drivers/gpu/drm/i915/gt/intel_gt_ccs_mode.c index cbabeb503d3b..8364523f2730 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_ccs_mode.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_ccs_mode.c @@ -6,6 +6,7 @@ #include "i915_drv.h" #include "intel_engine_user.h" #include "intel_gt_ccs_mode.h" +#include "intel_gt_pm.h" #include "intel_gt_print.h" #include "intel_gt_regs.h" #include "intel_gt_sysfs.h" @@ -172,7 +173,7 @@ static int rb_engine_cmp(struct rb_node *rb_new, const struct rb_node *rb_old) return new->uabi_class - old->uabi_class; } -static void __maybe_unused add_uabi_ccs_engines(struct intel_gt *gt, u32 ccs_mode) +static void add_uabi_ccs_engines(struct intel_gt *gt, u32 ccs_mode) { struct drm_i915_private *i915 = gt->i915; intel_engine_mask_t new_ccs_mask, tmp; @@ -234,7 +235,7 @@ static void __maybe_unused add_uabi_ccs_engines(struct intel_gt *gt, u32 ccs_mod mutex_unlock(&i915->uabi_engines_mutex); } -static void __maybe_unused remove_uabi_ccs_engines(struct intel_gt *gt, u8 ccs_mode) +static void remove_uabi_ccs_engines(struct intel_gt *gt, u8 ccs_mode) { struct drm_i915_private *i915 = gt->i915; intel_engine_mask_t new_ccs_mask, tmp; @@ -277,8 +278,85 @@ static ssize_t num_cslices_show(struct device *dev, } static DEVICE_ATTR_RO(num_cslices); +static ssize_t ccs_mode_show(struct device *dev, + struct device_attribute *attr, char *buff) +{ + struct intel_gt *gt = kobj_to_gt(&dev->kobj); + u32 ccs_mode; + + ccs_mode = hweight32(gt->ccs.id_mask); + + return sysfs_emit(buff, "%u\n", ccs_mode); +} + +static ssize_t ccs_mode_store(struct device *dev, + struct device_attribute *attr, + const char *buff, size_t count) +{ + struct intel_gt *gt = kobj_to_gt(&dev->kobj); + int num_cslices = hweight32(CCS_MASK(gt)); + int ccs_mode = hweight32(gt->ccs.id_mask); + ssize_t ret; + u32 val; + + ret = kstrtou32(buff, 0, &val); + if (ret) + return ret; + + /* + * As of now possible values to be set are 1, 2, 4, + * up to the maximum number of available slices + */ + if (!val || val > num_cslices || (num_cslices % val)) + return -EINVAL; + + /* Let's wait until the GT is no longer in use */ + ret = intel_gt_pm_wait_for_idle(gt); + if (ret) + return ret; + + mutex_lock(>->wakeref.mutex); + + /* + * Let's check again that the GT is idle, + * we don't want to change the CCS mode + * while someone is using the GT + */ + if (intel_gt_pm_is_awake(gt)) { + ret = -EBUSY; + goto out; + } + + /* + * Nothing to do if the requested setting + * is the same as the current one + */ + if (val == ccs_mode) + goto out; + else if (val > ccs_mode) + add_uabi_ccs_engines(gt, val); + else + remove_uabi_ccs_engines(gt, val); + +out: + mutex_unlock(>->wakeref.mutex); + + return ret ?: count; +} +static DEVICE_ATTR_RW(ccs_mode); + void intel_gt_sysfs_ccs_init(struct intel_gt *gt) { if (sysfs_create_file(>->sysfs_gt, &dev_attr_num_cslices.attr)) gt_warn(gt, "Failed to create sysfs num_cslices files\n"); + + /* + * Do not create the ccs_mode file for non DG2 platforms + * because they don't need it as they have only one CCS engine + */ + if (!IS_DG2(gt->i915)) + return; + + if (sysfs_create_file(>->sysfs_gt, &dev_attr_ccs_mode.attr)) + gt_warn(gt, "Failed to create sysfs ccs_mode files\n"); }