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From: <mhonap@nvidia.com>
To: <alex@shazbot.org>, <jgg@ziepe.ca>, <ankita@nvidia.com>,
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Cc: <cjia@nvidia.com>, <kjaju@nvidia.com>, <vsethi@nvidia.com>,
	<zhiw@nvidia.com>, <mhonap@nvidia.com>,
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Subject: [PATCH v4 03/27] cxl: Move component register defines to uapi/cxl/cxl_regs.h
Date: Thu, 13 Aug 2026 15:06:07 +0530	[thread overview]
Message-ID: <20260813093631.2288172-4-mhonap@nvidia.com> (raw)
In-Reply-To: <20260813093631.2288172-1-mhonap@nvidia.com>

From: Manish Honap <mhonap@nvidia.com>

The CXL component and HDM decoder register layout is spec-defined and is
needed by consumers outside the CXL subsystem such as vfio-cxl, which
cannot include the private drivers/cxl/cxl.h. Move those defines to a new
uapi header, the way PCI register offsets live in uapi pci_regs.h, and
include it from drivers/cxl/cxl.h so existing users are unchanged.

No functional change; the GENMASK and BIT forms are written as plain
values as an uAPI header requirement.

Signed-off-by: Manish Honap <mhonap@nvidia.com>
---
 MAINTAINERS                 |  1 +
 drivers/cxl/cxl.h           | 47 +-----------------------------
 include/uapi/cxl/cxl_regs.h | 58 +++++++++++++++++++++++++++++++++++++
 3 files changed, 60 insertions(+), 46 deletions(-)
 create mode 100644 include/uapi/cxl/cxl_regs.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 5114e6db7307..c665bf8f1a28 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6528,6 +6528,7 @@ F:	Documentation/driver-api/cxl
 F:	Documentation/userspace-api/fwctl/fwctl-cxl.rst
 F:	drivers/cxl/
 F:	include/cxl/
+F:	include/uapi/cxl/
 F:	include/uapi/linux/cxl_mem.h
 F:	tools/testing/cxl/
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index c795cce0fcbc..2893b2427be1 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -13,6 +13,7 @@
 #include <linux/io.h>
 #include <linux/range.h>
 #include <cxl/cxl.h>
+#include <cxl/cxl_regs.h>
 
 extern const struct nvdimm_security_ops *cxl_security_ops;
 
@@ -24,52 +25,6 @@ extern const struct nvdimm_security_ops *cxl_security_ops;
  * (port-driver, region-driver, nvdimm object-drivers... etc).
  */
 
-/* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
-#define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
-
-/* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
-#define CXL_CM_OFFSET 0x1000
-#define CXL_CM_CAP_HDR_OFFSET 0x0
-#define   CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0)
-#define     CM_CAP_HDR_CAP_ID 1
-#define   CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16)
-#define     CM_CAP_HDR_CAP_VERSION 1
-#define   CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20)
-#define     CM_CAP_HDR_CACHE_MEM_VERSION 1
-#define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
-#define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
-
-#define   CXL_CM_CAP_CAP_ID_RAS 0x2
-#define   CXL_CM_CAP_CAP_ID_HDM 0x5
-#define   CXL_CM_CAP_CAP_HDM_VERSION 1
-
-/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
-#define CXL_HDM_DECODER_CAP_OFFSET 0x0
-#define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
-#define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
-#define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
-#define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
-#define   CXL_HDM_DECODER_INTERLEAVE_3_6_12_WAY BIT(11)
-#define   CXL_HDM_DECODER_INTERLEAVE_16_WAY BIT(12)
-#define CXL_HDM_DECODER_CTRL_OFFSET 0x4
-#define   CXL_HDM_DECODER_ENABLE BIT(1)
-#define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
-#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
-#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
-#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
-#define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
-#define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
-#define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
-#define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
-#define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
-#define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
-#define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
-#define   CXL_HDM_DECODER0_CTRL_HOSTONLY BIT(12)
-#define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
-#define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
-#define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
-#define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
-
 /* HDM decoder control register constants CXL 3.0 8.2.5.19.7 */
 #define CXL_DECODER_MIN_GRANULARITY 256
 #define CXL_DECODER_MAX_ENCODED_IG 6
diff --git a/include/uapi/cxl/cxl_regs.h b/include/uapi/cxl/cxl_regs.h
new file mode 100644
index 000000000000..04bf790f0fdc
--- /dev/null
+++ b/include/uapi/cxl/cxl_regs.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Copyright (c) 2026 NVIDIA Corporation & Affiliates */
+
+#ifndef _UAPI_CXL_REGS_H_
+#define _UAPI_CXL_REGS_H_
+
+/*
+ * CXL Component Register layout from the CXL specification. Kept in uapi so a
+ * VMM can consume the register offsets without a kernel header dependency.
+ */
+
+/* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
+#define CXL_COMPONENT_REG_BLOCK_SIZE 0x10000
+
+/* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers */
+#define CXL_CM_OFFSET 0x1000
+#define CXL_CM_CAP_HDR_OFFSET 0x0
+#define   CXL_CM_CAP_HDR_ID_MASK 0xffff
+#define     CM_CAP_HDR_CAP_ID 1
+#define   CXL_CM_CAP_HDR_VERSION_MASK 0xf0000
+#define     CM_CAP_HDR_CAP_VERSION 1
+#define   CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK 0xf00000
+#define     CM_CAP_HDR_CACHE_MEM_VERSION 1
+#define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK 0xff000000
+#define CXL_CM_CAP_PTR_MASK 0xfff00000
+
+#define   CXL_CM_CAP_CAP_ID_RAS 0x2
+#define   CXL_CM_CAP_CAP_ID_HDM 0x5
+#define   CXL_CM_CAP_CAP_HDM_VERSION 1
+
+/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
+#define CXL_HDM_DECODER_CAP_OFFSET 0x0
+#define   CXL_HDM_DECODER_COUNT_MASK 0xf
+#define   CXL_HDM_DECODER_TARGET_COUNT_MASK 0xf0
+#define   CXL_HDM_DECODER_INTERLEAVE_11_8 0x100
+#define   CXL_HDM_DECODER_INTERLEAVE_14_12 0x200
+#define   CXL_HDM_DECODER_INTERLEAVE_3_6_12_WAY 0x800
+#define   CXL_HDM_DECODER_INTERLEAVE_16_WAY 0x1000
+#define CXL_HDM_DECODER_CTRL_OFFSET 0x4
+#define   CXL_HDM_DECODER_ENABLE 0x2
+#define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
+#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
+#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
+#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
+#define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
+#define   CXL_HDM_DECODER0_CTRL_IG_MASK 0xf
+#define   CXL_HDM_DECODER0_CTRL_IW_MASK 0xf0
+#define   CXL_HDM_DECODER0_CTRL_LOCK 0x100
+#define   CXL_HDM_DECODER0_CTRL_COMMIT 0x200
+#define   CXL_HDM_DECODER0_CTRL_COMMITTED 0x400
+#define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR 0x800
+#define   CXL_HDM_DECODER0_CTRL_HOSTONLY 0x1000
+#define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
+#define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
+#define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
+#define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
+
+#endif /* _UAPI_CXL_REGS_H_ */
-- 
2.25.1


  parent reply	other threads:[~2026-08-13  9:38 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-13  9:36 [PATCH v4 00/27] vfio/pci: Add CXL Type-2 device passthrough support mhonap
2026-08-13  9:36 ` [PATCH v4 01/27] cxl: Fix resource.c include path and export cxl_restore_hdm_after_pci_reset mhonap
2026-08-13  9:36 ` [PATCH v4 02/27] cxl/regs: Skip sub-block region request for BAR-owning drivers mhonap
2026-08-13  9:36 ` mhonap [this message]
2026-08-13  9:36 ` [PATCH v4 04/27] cxl: Establish media readiness in cxl_mem_probe() mhonap
2026-08-13  9:36 ` [PATCH v4 05/27] cxl: Add a function-scoped reset entry for vfio-pci mhonap
2026-08-13  9:36 ` [PATCH v4 06/27] vfio/pci: Add CXL ops registration interface mhonap
2026-08-13  9:36 ` [PATCH v4 07/27] vfio/pci: Detect CXL devices and load vfio-cxl on demand mhonap
2026-08-13  9:36 ` [PATCH v4 08/27] vfio/cxl: Add the vfio-cxl module skeleton mhonap
2026-08-13  9:36 ` [PATCH v4 09/27] vfio/cxl: Create the CXL memory device at bind mhonap
2026-08-13  9:36 ` [PATCH v4 10/27] vfio/cxl: Reject unsupported decoder topologies " mhonap
2026-08-13  9:36 ` [PATCH v4 11/27] vfio/cxl: Own the whole component register BAR mhonap
2026-08-13  9:36 ` [PATCH v4 12/27] vfio/pci: Let a provider exclude a BAR sub-range from mmap mhonap
2026-08-13  9:36 ` [PATCH v4 13/27] vfio/pci: Refuse read/write to an excluded BAR sub-range mhonap
2026-08-13  9:36 ` [PATCH v4 14/27] vfio: Add CXL region type for the HDM region mhonap
2026-08-13  9:36 ` [PATCH v4 15/27] vfio/pci: Call CXL open and close hooks around device use mhonap
2026-08-13  9:36 ` [PATCH v4 16/27] vfio/cxl: Shadow the CXL DVSEC body at open mhonap
2026-08-13  9:36 ` [PATCH v4 17/27] vfio/cxl: Virtualize the CXL DVSEC mhonap
2026-08-13  9:36 ` [PATCH v4 18/27] vfio/cxl: Expose the HDM memory and trap the decoder registers mhonap
2026-08-13  9:36 ` [PATCH v4 19/27] vfio/cxl: Keep the HDM decoder block off the direct BAR mapping mhonap
2026-08-13  9:36 ` [PATCH v4 20/27] vfio/cxl: Emulate the HDM decoder commit handshake mhonap
2026-08-13  9:36 ` [PATCH v4 21/27] vfio/cxl: Describe the CXL device and decoder geometry to userspace mhonap
2026-08-13  9:36 ` [PATCH v4 22/27] vfio/cxl: Revoke the HDM mapping on reset and power transitions mhonap
2026-08-13  9:36 ` [PATCH v4 23/27] vfio/cxl: Refresh the decoder snapshot after a device reset mhonap
2026-08-13  9:36 ` [PATCH v4 24/27] vfio/cxl: Service a guest-triggered CXL reset mhonap
2026-08-13  9:36 ` [PATCH v4 25/27] vfio/pci: Provide an opt-out for the CXL Type-2 extensions mhonap
2026-08-13  9:36 ` [PATCH v4 26/27] Documentation: vfio-pci: Document CXL Type-2 device passthrough mhonap
2026-08-13  9:36 ` [PATCH v4 27/27] selftests/vfio: Add CXL Type-2 passthrough corner-case tests mhonap

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