From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3F7F35476D5; Mon, 31 Aug 2026 13:46:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183979; cv=none; b=SMrjPNkMdwhDDI0IQYqldS5RZVF82JBqPg/hGfFTOHrbtyir6JwXIgcAfWKXFTwxB6AohmeYe530LmWj8fE1YhM0xQTbROqfpDR/GtIcakD9qb8uc0kT7g1PD5wrO5eR6xPkXsDvLQskWvY9I03NNPee2CDkrtKW5BEQMzzBB8A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183979; c=relaxed/simple; bh=nwVoEls4/fzw0QpPFImmbtmw4hiSY6c0W1IcOGiAgEI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=fVIrtHoYohIVyyj9DWQS/tmepp7u2rOhFaAXs2XYo8SmTXX8/H/AcZIw2sMbxVil5mg23LUNbMPBpZfSonLAnTCHO6dZY7XCv5ERsZvUAxD+A6PNk4n4CpCy+sRz9ptSVdCgMQDDVMqvtpOzw4nO7/OcB7VSA+yAsJxOu08reXA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vFeyI+Nq; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="vFeyI+Nq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 26EA41F000E9; Mon, 31 Aug 2026 13:46:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788183976; bh=Sz2UMQSlEHhIZEOM4oB7B/YkTKXdNKKkx57d2oGKwmg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=vFeyI+Nq2HHfF652Dz/9Gp7A/Uv5k7QeFeMPrwURI3YHTRhm7dqc0AKD4ODbmM3Ff GCDKyJfR+MxfzWV7DoN+fh9XmT3yqhyYZTZMh2FhtNNz3R/E4cTOI3gAIKm246JRAH 6hoIcJfMSQRmY3ci1G7ZtzsVGCjrlr9c6XLHRYOE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gwan-gyeong Mun , Matthew Auld , Jia Yao , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Sasha Levin Subject: [PATCH 6.18 03/83] drm/xe/guc_ads: allocate UM queues in a separate BO Date: Mon, 31 Aug 2026 15:33:39 +0200 Message-ID: <20260831133359.368556334@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260831133359.207714926@linuxfoundation.org> References: <20260831133359.207714926@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jia Yao commit 99b01815957bd7d848420cb697f79ed11f7f215c upstream. Move the UM queues into a dedicated BO (ads->um_queue_bo) and avoid CPU memset operations on it, which eliminates the CPU as a potential cacheline-polluting agent and helps maintain consistency between GAM writes and GuC reads. We also need to ensure the base_dpa for the queue is contiguous on hw where this is used instead of a GGTT address. Another good reason to split this out to a separate BO. Fixes: 9c57bc08652a ("drm/xe/lnl: Drop force_probe requirement") Cc: Gwan-gyeong Mun Cc: Matthew Auld Cc: # v6.12+ Signed-off-by: Jia Yao Reviewed-by: Matthew Auld Signed-off-by: Matthew Auld Link: https://patch.msgid.link/20260804165057.129529-2-jia.yao@intel.com (cherry picked from commit 99b01815957bd7d848420cb697f79ed11f7f215c) Signed-off-by: Thomas Hellström Signed-off-by: Sasha Levin --- drivers/gpu/drm/xe/xe_bo.h | 14 +++++ drivers/gpu/drm/xe/xe_guc.c | 6 ++ drivers/gpu/drm/xe/xe_guc_ads.c | 89 +++++++++++++++++---------- drivers/gpu/drm/xe/xe_guc_ads_types.h | 5 ++ 4 files changed, 82 insertions(+), 32 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h index fef60c8a4e5b1..71169b57fbda4 100644 --- a/drivers/gpu/drm/xe/xe_bo.h +++ b/drivers/gpu/drm/xe/xe_bo.h @@ -6,6 +6,7 @@ #ifndef _XE_BO_H_ #define _XE_BO_H_ +#include #include #include "xe_bo_types.h" @@ -455,6 +456,19 @@ void xe_bo_dev_fini(struct xe_bo_dev *bo_device); struct sg_table *xe_bo_sg(struct xe_bo *bo); +/** + * xe_bo_sg_is_contiguous() - Check if a BO's DMA address space is contiguous. + * @bo: the BO to check (must have a valid sg table, i.e. !xe_bo_is_vram()) + * @len: required contiguous length in bytes + * + * Returns true if the first @len bytes of the BO are mapped to a contiguous + * DMA address range. + */ +static inline bool xe_bo_sg_is_contiguous(struct xe_bo *bo, size_t len) +{ + return drm_prime_get_contiguous_size(xe_bo_sg(bo)) >= len; +} + /* * xe_sg_segment_size() - Provides upper limit for sg segment size. * @dev: device pointer diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c index ae0c88da422b2..cc5741f751b93 100644 --- a/drivers/gpu/drm/xe/xe_guc.c +++ b/drivers/gpu/drm/xe/xe_guc.c @@ -700,6 +700,12 @@ static int xe_guc_realloc_post_hwconfig(struct xe_guc *guc) if (ret) return ret; + if (guc->ads.um_queue_bo) { + ret = xe_managed_bo_reinit_in_vram(xe, tile, &guc->ads.um_queue_bo); + if (ret) + return ret; + } + return 0; } diff --git a/drivers/gpu/drm/xe/xe_guc_ads.c b/drivers/gpu/drm/xe/xe_guc_ads.c index db71823b25380..86e6651c00363 100644 --- a/drivers/gpu/drm/xe/xe_guc_ads.c +++ b/drivers/gpu/drm/xe/xe_guc_ads.c @@ -65,10 +65,14 @@ ads_to_map(struct xe_guc_ads *ads) /* * The Additional Data Struct (ADS) has pointers for different buffers used by - * the GuC. One single gem object contains the ADS struct itself (guc_ads) and - * all the extra buffers indirectly linked via the ADS struct's entries. + * the GuC. One gem object (ads->bo) contains the ADS struct itself (guc_ads) + * and most of the extra buffers linked via the ADS struct's entries. The UM + * fault queues (PAGE_FAULT, PAGE_FAULT_RESPONSE, ACCESS_COUNTER rings) are + * kept in a separate BO (ads->um_queue_bo) so that the full memset of ads->bo + * performed on every GT reset does not discard fault descriptors already + * written into the rings by the GPU. * - * Layout of the ADS blob allocated for the GuC: + * Layout of the ADS blob (ads->bo): * * +---------------------------------------+ <== base * | guc_ads | @@ -100,10 +104,6 @@ ads_to_map(struct xe_guc_ads *ads) * +---------------------------------------+ * | padding | * +---------------------------------------+ <== 4K aligned - * | UM queues | - * +---------------------------------------+ - * | padding | - * +---------------------------------------+ <== 4K aligned * | private data | * +---------------------------------------+ * | padding | @@ -157,16 +157,6 @@ static size_t guc_ads_capture_size(struct xe_guc_ads *ads) return PAGE_ALIGN(ads->capture_size); } -static size_t guc_ads_um_queues_size(struct xe_guc_ads *ads) -{ - struct xe_device *xe = ads_to_xe(ads); - - if (!xe->info.has_usm) - return 0; - - return GUC_UM_QUEUE_SIZE * GUC_UM_HW_QUEUE_MAX; -} - static size_t guc_ads_private_data_size(struct xe_guc_ads *ads) { return PAGE_ALIGN(ads_to_guc(ads)->fw.private_data_size); @@ -207,22 +197,12 @@ static size_t guc_ads_capture_offset(struct xe_guc_ads *ads) return PAGE_ALIGN(offset); } -static size_t guc_ads_um_queues_offset(struct xe_guc_ads *ads) -{ - u32 offset; - - offset = guc_ads_capture_offset(ads) + - guc_ads_capture_size(ads); - - return PAGE_ALIGN(offset); -} - static size_t guc_ads_private_data_offset(struct xe_guc_ads *ads) { size_t offset; - offset = guc_ads_um_queues_offset(ads) + - guc_ads_um_queues_size(ads); + offset = guc_ads_capture_offset(ads) + + guc_ads_capture_size(ads); return PAGE_ALIGN(offset); } @@ -408,6 +388,45 @@ int xe_guc_ads_init(struct xe_guc_ads *ads) ads->bo = bo; + if (xe->info.has_usm) { + /* + * Allocate a separate BO for the HW fault ring (UM queues). + * + * Round the size up to the next power of two so that + * (system memory, no IOMMU) the TTM pool issues a single + * alloc_pages(order=N) call, maximising the chance of getting + * a physically contiguous block. GuC requires contiguous DPA. + */ + size_t um_size = roundup_pow_of_two(GUC_UM_QUEUE_SIZE * + GUC_UM_HW_QUEUE_MAX); + + u32 um_flags = XE_BO_FLAG_SYSTEM | + XE_BO_FLAG_GGTT | + XE_BO_FLAG_GGTT_INVALIDATE | + XE_BO_FLAG_PINNED_NORESTORE; + + bo = xe_managed_bo_create_pin_map(xe, tile, um_size, um_flags); + if (IS_ERR(bo)) + return PTR_ERR(bo); + + /* + * On pre-Xe3p platforms, GAM (not GuC) accesses the UM queue + * ring via base_dpa, which must be a contiguous DMA address + * range. Verify that the allocated pages are contiguous in + * DMA address space. + */ + if (!xe_bo_is_vram(bo) && + unlikely(!xe_bo_sg_is_contiguous(bo, + GUC_UM_QUEUE_SIZE * + GUC_UM_HW_QUEUE_MAX))) { + drm_err(&xe->drm, + "UM fault queue memory is not contiguous in DMA address space; GAM requires contiguous DPA\n"); + return -ENOMEM; + } + + ads->um_queue_bo = bo; + } + return 0; } ALLOW_ERROR_INJECTION(xe_guc_ads_init, ERRNO); /* See xe_pci_probe() */ @@ -824,13 +843,19 @@ static void guc_mmio_reg_state_init(struct xe_guc_ads *ads) static void guc_um_init_params(struct xe_guc_ads *ads) { - u32 um_queue_offset = guc_ads_um_queues_offset(ads); + struct xe_bo *um_bo = ads->um_queue_bo; u64 base_dpa; u32 base_ggtt; int i; - base_ggtt = xe_bo_ggtt_addr(ads->bo) + um_queue_offset; - base_dpa = xe_bo_main_addr(ads->bo, PAGE_SIZE) + um_queue_offset; + if (um_bo) { + /* All USM platforms: UM queues in dedicated um_queue_bo */ + base_ggtt = xe_bo_ggtt_addr(um_bo); + base_dpa = xe_bo_main_addr(um_bo, PAGE_SIZE); + } else { + /* Platform does not support USM: no UM queues, nothing to do */ + return; + } for (i = 0; i < GUC_UM_HW_QUEUE_MAX; ++i) { ads_blob_write(ads, um_init_params.queue_params[i].base_dpa, diff --git a/drivers/gpu/drm/xe/xe_guc_ads_types.h b/drivers/gpu/drm/xe/xe_guc_ads_types.h index 70c132458ac38..acb5366f76efe 100644 --- a/drivers/gpu/drm/xe/xe_guc_ads_types.h +++ b/drivers/gpu/drm/xe/xe_guc_ads_types.h @@ -16,6 +16,11 @@ struct xe_bo; struct xe_guc_ads { /** @bo: XE BO for GuC ads blob */ struct xe_bo *bo; + /** + * @um_queue_bo: Dedicated BO for the HW fault ring (UM queues). + * NULL if the platform does not support USM. + */ + struct xe_bo *um_queue_bo; /** @golden_lrc_size: golden LRC size */ size_t golden_lrc_size; /** @regset_size: size of register set passed to GuC for save/restore */ -- 2.53.0