From patchwork Wed Feb 16 17:41:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas De Marchi X-Patchwork-Id: 12748856 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 35AAEC433F5 for ; Wed, 16 Feb 2022 17:40:53 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C482810E6EC; Wed, 16 Feb 2022 17:40:52 +0000 (UTC) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id E88BC10E6EC; Wed, 16 Feb 2022 17:40:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1645033251; x=1676569251; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=pyIoVRN8++7oRug/siRQt3WhGGOKaIEWMAd12oFQ2fo=; b=APNCMHlxSDv9av6WbD3iap2XkrNViP9ZK/NJAglUXOnqucz0+giuDNwB 2lGoU/IcKQe2d6nVNpwAwQS8SmjemSblfPC98/jSfFfPHU4AthdaNzpDd MCa5ylejjRN+i3O0sCNyvgXvdKvVxQ/exaGjIPMkNTpEkFz158Itm0jAt 1ZZ1cPlCazrwCpinZCRt9qVncTCDmZSnDwWhGXvnsOc8JAijTCGwtTHqb KSBJ5ic9FnLms6TxI8P5+pBxfVdKAhk2Zs5hSjdLDBQxl+EmdPqM9AqDi +qLRcJ9xqxm0eZSYq6ZGt4xa7U2nIggrD2JxkNogpumE2tbcxVArlYYco g==; X-IronPort-AV: E=McAfee;i="6200,9189,10260"; a="230641925" X-IronPort-AV: E=Sophos;i="5.88,374,1635231600"; d="scan'208";a="230641925" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Feb 2022 09:40:51 -0800 X-IronPort-AV: E=Sophos;i="5.88,374,1635231600"; d="scan'208";a="540226575" Received: from lucas-s2600cw.jf.intel.com ([10.165.21.202]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Feb 2022 09:40:51 -0800 From: Lucas De Marchi To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Date: Wed, 16 Feb 2022 09:41:31 -0800 Message-Id: <20220216174147.3073235-1-lucas.demarchi@intel.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v3 00/16] drm/i915/guc: Refactor ADS access to use iosys_map 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: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Lucas De Marchi , Sumit Semwal , Thomas Zimmermann , =?utf-8?q?Christian_K=C3=B6nig?= Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" original: https://patchwork.freedesktop.org/series/99378/ v2: https://patchwork.freedesktop.org/series/99711/#rev1, https://patchwork.freedesktop.org/series/99711/#rev2 Main changes from previous version: - Unrelated patches to iosys-map conversion have landed - Remove unecessary kernel.h include from iosys-map.h - Rebase on latest drm-tip Original cover letter: While porting i915 to arm64 we noticed some issues accessing lmem. Some writes were getting corrupted and the final state of the buffer didn't have exactly what we wrote. This became evident when enabling GuC submission: depending on the number of engines the ADS struct was being corrupted and GuC would reject it, refusin to initialize. From Documentation/core-api/bus-virt-phys-mapping.rst: This memory is called "PCI memory" or "shared memory" or "IO memory" or whatever, and there is only one way to access it: the readb/writeb and related functions. You should never take the address of such memory, because there is really nothing you can do with such an address: it's not conceptually in the same memory space as "real memory" at all, so you cannot just dereference a pointer. (Sadly, on x86 it **is** in the same memory space, so on x86 it actually works to just deference a pointer, but it's not portable). When reading or writing words directly to IO memory, in order to be portable the Linux kernel provides the abstraction detailed in section "Differences between I/O access functions" of Documentation/driver-api/device-io.rst. This limits our ability to simply overlay our structs on top a buffer and directly access it since that buffer may come from IO memory rather than system memory. Hence the approach taken in intel_guc_ads.c needs to be refactored. This is not the only place in i915 that need to be changed, but the one causing the most problems, with a real reproducer. This first set of patch focuses on fixing the gem object to pass the ADS After the addition of a few helpers in the dma_buf_map API, most of intel_guc_ads.c can be converted to use it. The exception is the regset initialization: we'd incur into a lot of extra indirection when reading/writing each register. So the regset is converted to use a temporary buffer allocated on probe, which is then copied to its final location when finishing the initialization or on gt reset. [v3: the part unrelated to iosys-map has already landed] Testing on some discrete cards, after this change we can correctly pass the ADS struct to GuC and have it initialized correctly. thanks Lucas De Marchi Lucas De Marchi (16): iosys-map: Add offset to iosys_map_memcpy_to() iosys-map: Add a few more helpers drm/i915/gt: Add helper for shmem copy to iosys_map drm/i915/guc: Keep iosys_map of ads_blob around drm/i915/guc: Add read/write helpers for ADS blob drm/i915/guc: Convert golden context init to iosys_map drm/i915/guc: Convert policies update to iosys_map drm/i915/guc: Convert engine record to iosys_map drm/i915/guc: Convert guc_ads_private_data_reset to iosys_map drm/i915/guc: Convert golden context prep to iosys_map drm/i915/guc: Replace check for golden context size drm/i915/guc: Convert mapping table to iosys_map drm/i915/guc: Convert capture list to iosys_map drm/i915/guc: Convert guc_mmio_reg_state_init to iosys_map drm/i915/guc: Convert __guc_ads_init to iosys_map drm/i915/guc: Remove plain ads_blob pointer drivers/gpu/drm/drm_cache.c | 2 +- drivers/gpu/drm/drm_fb_helper.c | 2 +- drivers/gpu/drm/i915/gt/shmem_utils.c | 32 +++ drivers/gpu/drm/i915/gt/shmem_utils.h | 3 + drivers/gpu/drm/i915/gt/uc/intel_guc.h | 7 +- drivers/gpu/drm/i915/gt/uc/intel_guc_ads.c | 233 ++++++++++-------- drivers/gpu/drm/i915/gt/uc/intel_guc_ads.h | 3 +- .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 17 +- include/linux/iosys-map.h | 218 +++++++++++++++- 9 files changed, 396 insertions(+), 121 deletions(-)