{"id":2221927,"url":"http://patchwork.ozlabs.org/api/1.1/covers/2221927/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-pci/cover/20260410-sdxi-base-v1-0-1d184cb5c60a@amd.com/","project":{"id":28,"url":"http://patchwork.ozlabs.org/api/1.1/projects/28/?format=json","name":"Linux PCI development","link_name":"linux-pci","list_id":"linux-pci.vger.kernel.org","list_email":"linux-pci@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null},"msgid":"<20260410-sdxi-base-v1-0-1d184cb5c60a@amd.com>","date":"2026-04-10T13:07:10","name":"[00/23] dmaengine: Smart Data Accelerator Interface (SDXI) basic support","submitter":{"id":91626,"url":"http://patchwork.ozlabs.org/api/1.1/people/91626/?format=json","name":"Nathan Lynch via B4 Relay","email":"devnull+nathan.lynch.amd.com@kernel.org"},"mbox":"http://patchwork.ozlabs.org/project/linux-pci/cover/20260410-sdxi-base-v1-0-1d184cb5c60a@amd.com/mbox/","series":[{"id":499458,"url":"http://patchwork.ozlabs.org/api/1.1/series/499458/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-pci/list/?series=499458","date":"2026-04-10T13:07:10","name":"dmaengine: Smart Data Accelerator Interface (SDXI) basic support","version":1,"mbox":"http://patchwork.ozlabs.org/series/499458/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/covers/2221927/comments/","headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pci@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=JBqfXyEb;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c04:e001:36c::12fc:5321; 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a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1775826469; cv=none;\n b=XB8HA/BIQE9Ng0aPTlnszJs74YzLT3nMdRTFsf+Rm+oVNcL5GBUxhXRNkTso9OjvJ2L6W2Q9qemow8J/vg95duH0ay/ctxjwN0vEHWvUACCAsoH9KwPaV0+2hV2wn5NYru2ZyTMNh1QSW9y99WrumQRcOYfkQNgom3kHV/bym44=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1775826469; c=relaxed/simple;\n\tbh=9rBcO8VxjER3OnuYfoq9G9H5KIuoJGxGfKEMHDiZlyY=;\n\th=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc;\n b=nmZAaZiWXH3982FuuNty6wcuiYts45+rNU/OMBdC1EsD/2ootKfiDUSlNkTP8f/SZ/TTLvbl1nIjlBq7By/k6JyymUhqCYGlv9kdf6F0Vv0AilDIJosawjIYHF2GaPkw9y9e72EAgYsOhQ2AtA/N9eMCYi2TSaDsPwhwsiBp7gU=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=JBqfXyEb; arc=none smtp.client-ip=10.30.226.201","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1775826469;\n\tbh=9rBcO8VxjER3OnuYfoq9G9H5KIuoJGxGfKEMHDiZlyY=;\n\th=From:Subject:Date:To:Cc:Reply-To:From;\n\tb=JBqfXyEb9TOT8FgY/nbT253IAXAJWn6WZXPN4ECiK0zkxL8r0ZdUm7ivM6yFvmx/+\n\t X0gypKP5qvXxp1oFFfeCUhf1WLxVBIizLagwF55RfkvU59V752i0H3a2+9JBm9wv/H\n\t BFKmo60dOGs0Xclw2gsZDZ8r39OmFE7cySVUaRtVuG6065THkKCCa81tjN7DdC//4T\n\t eWlaPXRsnVq+MGLDx8T182DCXVlzgJcHAJNPX2gFVum4/2Oic3rNULkkRJVzrxvrVk\n\t AeglrkNCCo5Womy993S9+W2pri7JZF7VBMHp6z9pBA5/DKLEGi4wqVBxhvRbram7GX\n\t BQD+GizXJzQng==","From":"Nathan Lynch via B4 Relay ","Subject":"[PATCH 00/23] dmaengine: Smart Data Accelerator Interface (SDXI)\n basic support","Date":"Fri, 10 Apr 2026 08:07:10 -0500","Message-Id":"<20260410-sdxi-base-v1-0-1d184cb5c60a@amd.com>","Precedence":"bulk","X-Mailing-List":"linux-pci@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","Content-Type":"text/plain; charset=\"utf-8\"","Content-Transfer-Encoding":"7bit","X-B4-Tracking":"v=1; b=H4sIAAAAAAAC/02MQQrCMBBFr1JmbSSTGGJceQ9xkWZGm0Ub6JSgl\n NzdoBtXnwf/vR2E18wCl2GHlWuWXJYOeBggTXF5ssrUGYw2Tp/RKqFXVmMUVt6ST+FBiZ2H/p+\n ybGV9f1MV+9x+VtDuz6qotCJtTxjRBDPGa5zpmMoM99baBxF+B9CQAAAA","X-Change-ID":"20250813-sdxi-base-73d7c9fdce57","To":"Vinod Koul ","Cc":"Wei Huang ,\n Mario Limonciello ,\n Bjorn Helgaas ,\n Jonathan Cameron ,\n Stephen Bates , PradeepVineshReddy.Kodamati@amd.com,\n John.Kariuki@amd.com, linux-pci@vger.kernel.org,\n linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org,\n Nathan Lynch ","X-Mailer":"b4 0.15.2","X-Developer-Signature":"v=1; a=ed25519-sha256; t=1775826467; l=6024;\n i=nathan.lynch@amd.com; s=20260410; h=from:subject:message-id;\n bh=9rBcO8VxjER3OnuYfoq9G9H5KIuoJGxGfKEMHDiZlyY=;\n b=gAwlqr9NKfu+gJarBGqfqo48zzVDQS3J4QnIesv9toDOQO891IMNga67nVexAyP4Pm4cjv4uW\n oxiFF3l5Vd7DriNYBpEMFpb7EjiywwC8C6tkz/ueyeKCXXbp7BcoEZv","X-Developer-Key":"i=nathan.lynch@amd.com; a=ed25519;\n pk=PK4ozhq+/z9/2Jl5rgDmvHa9raVomv79qM8p1RAFpEw=","X-Endpoint-Received":"by B4 Relay for nathan.lynch@amd.com/20260410 with\n auth_id=728","X-Original-From":"Nathan Lynch ","Reply-To":"nathan.lynch@amd.com"},"content":"The Smart Data Accelerator Interface (SDXI) is a vendor-neutral\narchitecture for memory-to-memory data movement offload designed for\nkernel bypass and virtualization.\n\nGeneral information on SDXI may be found at:\nhttps://www.snia.org/sdxi\n\nThis submission adds a driver with basic support for PCIe-hosted SDXI\n1.0 implementations and includes a DMA engine provider with memcpy\ncapability. A more limited RFC version was posted in September 2025;\nthe code has seen multiple substantial updates since then, described\nbelow.\n\nPlanned future SDXI work (out of scope for this series):\n\n* Character device for exposing SDXI contexts to user space.\n\n* Support for operation types to be added in future SDXI revisions.\n\n* Greater configurability for control structures, e.g. descriptor ring\n size.\n\nThe latest released version of the SDXI specification is 1.0:\nhttps://www.snia.org/sites/default/files/technical-work/sdxi/release/SNIA-SDXI-Specification-v1.0a.pdf\n\nDraft versions of future SDXI specifications in development may be found at:\nhttps://www.snia.org/tech_activities/publicreview#sdxi\n\n---\nChanges in v1:\n- Reorder series and introduce functionality incrementally while\n remaining buildable and functional at each step. (Jonathan Cameron)\n- Use devres APIs where possible for device resources (JC)\n- Use cleanup APIs to significantly reduce use of goto-oriented error\n unwinding. (JC)\n- Drop SDXI_DEBUG config option. (JC)\n- Cite SDXI spec version and section number consistently throughout. (JC)\n- Combine local variable declarations of same type. (JC)\n- Mark descriptor structs __packed. (JC)\n- Use designated initializers in descriptor encoding functions. (JC)\n- Prefer dev_err_probe() over sdxi_err() in sdxi_pci_init(). (JC)\n- Prune unnecessary includes throughout source files. (JC)\n- Remove unnecessary/unhelpful comments in several places. (JC)\n- Remove SDXI spec material from \"Add SNIA SDXI accelerator sub-class\"\n commit message and reword the remainder. (Bjorn Helgaas)\n- Remove unnecessary local for DMA_BIT_MASK() argument in\n sdxi_pci_init(). (BH)\n- Use \"{ }\" for final null entry in id table, not \"{ 0, }\". (BH)\n- Replace sample descriptor submission code from the SDXI spec with an\n improved API that has unit tests, eliminates a copy step for\n callers, and can block until ring space becomes available if\n desired.\n- Omit the error log facility for now; it can be reintroduced later.\n- Use a per-device xarray to allocate context IDs and map them to\n context objects.\n- Implement interrupt-based completion signaling for memcpy operations\n in the DMA engine provider, DMA provider code mostly rewritten.\n\nNon-changes in v1:\n- Mario suggested that pci_clear_master() is needed in\n sdxi_pci_init()'s error path and in sdxi_pci_exit() (now\n sdxi_pci_remove()). However, sdxi uses pcim_enable_device(), which\n appears to ensure that master is cleared for the device. Happy to\n revisit this if I'm mistaken.\n\n- Link to RFC: https://lore.kernel.org/r/20250905-sdxi-base-v1-0-d0341a1292ba@amd.com\n\n---\nNathan Lynch (23):\n PCI: Add SNIA SDXI accelerator sub-class\n MAINTAINERS: Add entry for SDXI driver\n dmaengine: sdxi: Add PCI initialization\n dmaengine: sdxi: Feature discovery and initial configuration\n dmaengine: sdxi: Configure context tables\n dmaengine: sdxi: Allocate DMA pools\n dmaengine: sdxi: Allocate administrative context\n dmaengine: sdxi: Install administrative context\n dmaengine: sdxi: Start functions on probe, stop on remove\n dmaengine: sdxi: Complete administrative context jump start\n dmaengine: sdxi: Add client context alloc and release APIs\n dmaengine: sdxi: Add descriptor ring management\n dmaengine: sdxi: Add unit tests for descriptor ring reservations\n dmaengine: sdxi: Attach descriptor ring state to contexts\n dmaengine: sdxi: Per-context access key (AKey) table entry allocator\n dmaengine: sdxi: Generic descriptor manipulation helpers\n dmaengine: sdxi: Add completion status block API\n dmaengine: sdxi: Encode context start, stop, and sync descriptors\n dmaengine: sdxi: Provide context start and stop APIs\n dmaengine: sdxi: Encode nop, copy, and interrupt descriptors\n dmaengine: sdxi: Add unit tests for descriptor encoding\n dmaengine: sdxi: MSI/MSI-X vector allocation and mapping\n dmaengine: sdxi: Add DMA engine provider\n\n MAINTAINERS | 7 +\n drivers/dma/Kconfig | 2 +\n drivers/dma/Makefile | 1 +\n drivers/dma/sdxi/.kunitconfig | 4 +\n drivers/dma/sdxi/Kconfig | 18 ++\n drivers/dma/sdxi/Makefile | 16 ++\n drivers/dma/sdxi/completion.c | 79 ++++++\n drivers/dma/sdxi/completion.h | 24 ++\n drivers/dma/sdxi/context.c | 504 ++++++++++++++++++++++++++++++++++++\n drivers/dma/sdxi/context.h | 105 ++++++++\n drivers/dma/sdxi/descriptor.c | 198 ++++++++++++++\n drivers/dma/sdxi/descriptor.h | 135 ++++++++++\n drivers/dma/sdxi/descriptor_kunit.c | 484 ++++++++++++++++++++++++++++++++++\n drivers/dma/sdxi/device.c | 333 ++++++++++++++++++++++++\n drivers/dma/sdxi/dma.c | 497 +++++++++++++++++++++++++++++++++++\n drivers/dma/sdxi/dma.h | 12 +\n drivers/dma/sdxi/hw.h | 254 ++++++++++++++++++\n drivers/dma/sdxi/mmio.h | 57 ++++\n drivers/dma/sdxi/pci.c | 120 +++++++++\n drivers/dma/sdxi/ring.c | 158 +++++++++++\n drivers/dma/sdxi/ring.h | 84 ++++++\n drivers/dma/sdxi/ring_kunit.c | 105 ++++++++\n drivers/dma/sdxi/sdxi.h | 149 +++++++++++\n include/linux/pci_ids.h | 1 +\n 24 files changed, 3347 insertions(+)\n---\nbase-commit: c03d8b5462bcb0022f9477d09eb37dae66c3a769\nchange-id: 20250813-sdxi-base-73d7c9fdce57\n\nBest regards,\n-- \nNathan Lynch "}