From: Dave Jiang <dave.jiang@intel.com>
To: linux-cxl@vger.kernel.org
Cc: dan.j.williams@intel.com, ira.weiny@intel.com,
vishal.l.verma@intel.com, alison.schofield@intel.com,
Jonathan.Cameron@huawei.com, dave@stgolabs.net, jgg@nvidia.com,
shiju.jose@huawei.com
Subject: [PATCH v2 08/16] cxl: Add FWCTL support to the CXL memdev driver
Date: Fri, 31 Jan 2025 17:42:01 -0700 [thread overview]
Message-ID: <20250201004459.466499-9-dave.jiang@intel.com> (raw)
In-Reply-To: <20250201004459.466499-1-dave.jiang@intel.com>
Add fwctl support code to allow sending of CXL feature commands from
userspace through as ioctls via FWCTL. Provide initial setup bits.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
v2:
- Associate FWCTL with the 'cxl_memdev' through the memdev driver. (Dan)
- I'm leaving Jonathan's tag off to get this looked at again.
- Hide FWCTL code behind CONFIG_CXL_FWCTL (Dan)
---
drivers/cxl/Kconfig | 15 +++++++
drivers/cxl/Makefile | 1 +
drivers/cxl/features.c | 35 ++++++++++++---
drivers/cxl/features.h | 2 +
drivers/cxl/fwctl.c | 88 ++++++++++++++++++++++++++++++++++++++
include/cxl/features.h | 3 ++
include/uapi/fwctl/fwctl.h | 1 +
tools/testing/cxl/Kbuild | 1 +
8 files changed, 140 insertions(+), 6 deletions(-)
create mode 100644 drivers/cxl/fwctl.c
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
index 876469e23f7a..34731890bc8e 100644
--- a/drivers/cxl/Kconfig
+++ b/drivers/cxl/Kconfig
@@ -102,6 +102,21 @@ config CXL_MEM
If unsure say 'm'.
+config CXL_FWCTL
+ bool "CXL: Firmware Control support"
+ depends on CXL_MEM
+ select FWCTL
+ help
+ Enable support for firmware control of CXL devices. This allows
+ a FWCTL char device to be created in order to issue ioctls from
+ user space to exercise the CXL Features commands supported by
+ a CXL mailbox. There are some Features defined in the CXL spec
+ such as memory sparing. However a lof of those features are
+ exclusive to the kernel. Most likely the Features maniulated
+ by CXL_FWCTL will be vendor defined Features.
+
+ If unsure say 'n'.
+
config CXL_PORT
default CXL_BUS
tristate
diff --git a/drivers/cxl/Makefile b/drivers/cxl/Makefile
index 12fbc35081bb..cd28fb3bf855 100644
--- a/drivers/cxl/Makefile
+++ b/drivers/cxl/Makefile
@@ -18,4 +18,5 @@ cxl_port-y := port.o
cxl_acpi-y := acpi.o
cxl_pmem-y := pmem.o security.o
cxl_mem-y := mem.o features.o
+cxl_mem-$(CONFIG_CXL_FWCTL) += fwctl.o
cxl_pci-y := pci.o
diff --git a/drivers/cxl/features.c b/drivers/cxl/features.c
index 82598a409acc..2dcfefdfa6b3 100644
--- a/drivers/cxl/features.c
+++ b/drivers/cxl/features.c
@@ -1,8 +1,11 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2024-2025 Intel Corporation. All rights reserved. */
+#include <linux/pci.h>
#include <linux/device.h>
+#include <linux/module.h>
#include <cxl/mailbox.h>
#include <cxl/features.h>
+
#include "cxl.h"
#include "cxlmem.h"
#include "features.h"
@@ -168,11 +171,31 @@ static void enumerate_feature_cmds(struct cxl_memdev *cxlmd,
cxlfs->cap = CXL_FEATURES_RW;
}
+/* The __weak symbol gets replaced by FWCTL allocation function in fwctl.c */
+struct cxl_features_state * __weak devm_cxlfs_allocate(struct cxl_memdev *cxlmd)
+{
+ struct device *dev = &cxlmd->dev;
+ struct cxl_features_state *cxlfs =
+ devm_kzalloc(dev, sizeof(*cxlfs), GFP_KERNEL);
+
+ if (!cxlfs)
+ return ERR_PTR(-ENOMEM);
+
+ cxlfs->cxlmd = cxlmd;
+
+ return cxlfs;
+}
+
+/* The __weak symbol gets replaced by FWCTL free function in fwctl.c */
+void __weak devm_cxlfs_free(struct cxl_memdev *cxlmd)
+{
+ devm_kfree(&cxlmd->dev, cxlmd->cxlfs);
+ cxlmd->cxlfs = NULL;
+}
+
static void cxl_cxlfs_free(struct cxl_features_state *cxlfs)
{
- struct device *dev = &cxlfs->cxlmd->dev;
-
- devm_kfree(dev, cxlfs);
+ devm_cxlfs_free(cxlfs->cxlmd);
}
DEFINE_FREE(free_cxlfs, struct cxl_features_state *, if (_T) cxl_cxlfs_free(_T))
@@ -185,15 +208,13 @@ DEFINE_FREE(free_cxlfs, struct cxl_features_state *, if (_T) cxl_cxlfs_free(_T))
*/
int devm_cxl_add_features(struct cxl_memdev *cxlmd)
{
- struct device *dev = &cxlmd->dev;
int rc;
struct cxl_features_state *cxlfs __free(free_cxlfs) =
- devm_kzalloc(dev, sizeof(*cxlfs), GFP_KERNEL);
+ devm_cxlfs_allocate(cxlmd);
if (!cxlfs)
return -ENOMEM;
- cxlfs->cxlmd = cxlmd;
enumerate_feature_cmds(cxlmd, cxlfs);
rc = get_supported_features(cxlmd, cxlfs);
if (rc)
@@ -204,3 +225,5 @@ int devm_cxl_add_features(struct cxl_memdev *cxlmd)
return 0;
}
EXPORT_SYMBOL_NS_GPL(devm_cxl_add_features, "CXL");
+
+MODULE_IMPORT_NS("CXL");
diff --git a/drivers/cxl/features.h b/drivers/cxl/features.h
index 8706f944b476..e487c24ff06f 100644
--- a/drivers/cxl/features.h
+++ b/drivers/cxl/features.h
@@ -5,6 +5,8 @@
struct cxl_feat_entry;
+struct cxl_features_state *devm_cxlfs_allocate(struct cxl_memdev *cxlmd);
+void devm_cxlfs_free(struct cxl_memdev *cxlmd);
int devm_cxl_add_features(struct cxl_memdev *cxlmd);
bool is_cxl_feature_exclusive(struct cxl_feat_entry *entry);
diff --git a/drivers/cxl/fwctl.c b/drivers/cxl/fwctl.c
new file mode 100644
index 000000000000..d8fd68ac8982
--- /dev/null
+++ b/drivers/cxl/fwctl.c
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2025 Intel Corporation. All rights reserved. */
+#include <linux/fwctl.h>
+#include <linux/device.h>
+#include <cxl/features.h>
+#include "cxlmem.h"
+#include "features.h"
+
+static int cxlctl_open_uctx(struct fwctl_uctx *uctx)
+{
+ return 0;
+}
+
+static void cxlctl_close_uctx(struct fwctl_uctx *uctx)
+{
+}
+
+static void *cxlctl_info(struct fwctl_uctx *uctx, size_t *length)
+{
+ /* Place holder */
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
+static void *cxlctl_fw_rpc(struct fwctl_uctx *uctx, enum fwctl_rpc_scope scope,
+ void *rpc_in, size_t in_len, size_t *out_len)
+{
+ /* Place holder */
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
+static const struct fwctl_ops cxlctl_ops = {
+ .device_type = FWCTL_DEVICE_TYPE_CXL,
+ .uctx_size = sizeof(struct fwctl_uctx),
+ .open_uctx = cxlctl_open_uctx,
+ .close_uctx = cxlctl_close_uctx,
+ .info = cxlctl_info,
+ .fw_rpc = cxlctl_fw_rpc,
+};
+
+static void remove_cxlfs(void *_cxlfs)
+{
+ struct cxl_features_state *cxlfs = _cxlfs;
+ struct cxl_memdev *cxlmd = cxlfs->cxlmd;
+ struct fwctl_device *fwctl = &cxlfs->fwctl;
+
+ cxlmd->cxlfs = NULL;
+ fwctl_unregister(fwctl);
+ fwctl_put(fwctl);
+}
+
+DEFINE_FREE(free_cxlfs, struct cxl_features_state *, if (_T) fwctl_put(&_T->fwctl))
+
+static struct cxl_features_state *
+__devm_cxl_cfs_allocate(struct cxl_memdev *cxlmd, const struct fwctl_ops *ops)
+{
+ struct device *dev = &cxlmd->dev;
+ int rc;
+
+ struct cxl_features_state *cxlfs __free(free_cxlfs) =
+ fwctl_alloc_device(dev, ops, struct cxl_features_state, fwctl);
+ if (!cxlfs)
+ return ERR_PTR(-ENOMEM);
+
+ cxlfs->cxlmd = cxlmd;
+ rc = fwctl_register(&cxlfs->fwctl);
+ if (rc)
+ return ERR_PTR(rc);
+
+ rc = devm_add_action_or_reset(dev, remove_cxlfs, cxlfs);
+ if (rc)
+ return ERR_PTR(rc);
+
+ return no_free_ptr(cxlfs);
+}
+
+struct cxl_features_state *devm_cxlfs_allocate(struct cxl_memdev *cxlmd)
+{
+ return __devm_cxl_cfs_allocate(cxlmd, &cxlctl_ops);
+}
+EXPORT_SYMBOL_NS_GPL(devm_cxlfs_allocate, "CXL");
+
+void devm_cxlfs_free(struct cxl_memdev *cxlmd)
+{
+ devm_release_action(&cxlmd->dev, remove_cxlfs, cxlmd);
+}
+EXPORT_SYMBOL_NS_GPL(devm_cxlfs_free, "CXL");
+
+MODULE_IMPORT_NS("FWCTL");
diff --git a/include/cxl/features.h b/include/cxl/features.h
index 7ae84696d6dd..7c43ac021a8c 100644
--- a/include/cxl/features.h
+++ b/include/cxl/features.h
@@ -4,6 +4,7 @@
#define __CXL_FEATURES_H__
#include <linux/uuid.h>
+#include <linux/fwctl.h>
/* Feature UUIDs used by the kernel */
#define CXL_FEAT_PATROL_SCRUB_UUID \
@@ -57,6 +58,7 @@ enum cxl_features_capability {
/**
* struct cxl_features_state - The Features state for the device
+ * @fwctl: FWCTL device
* @cxlmd: Pointer to cxl mem device
* @cap: Feature commands capability
* @num_features: total Features supported by the device
@@ -64,6 +66,7 @@ enum cxl_features_capability {
* @entries: Feature detail entries fetched from the device
*/
struct cxl_features_state {
+ struct fwctl_device fwctl;
struct cxl_memdev *cxlmd;
enum cxl_features_capability cap;
int num_features;
diff --git a/include/uapi/fwctl/fwctl.h b/include/uapi/fwctl/fwctl.h
index f9b27fb5c161..4e4d30104667 100644
--- a/include/uapi/fwctl/fwctl.h
+++ b/include/uapi/fwctl/fwctl.h
@@ -43,6 +43,7 @@ enum {
enum fwctl_device_type {
FWCTL_DEVICE_TYPE_ERROR = 0,
FWCTL_DEVICE_TYPE_MLX5 = 1,
+ FWCTL_DEVICE_TYPE_CXL = 2,
};
/**
diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
index 6b0a992af4a7..6396d1296cef 100644
--- a/tools/testing/cxl/Kbuild
+++ b/tools/testing/cxl/Kbuild
@@ -47,6 +47,7 @@ cxl_port-y += cxl_port_test.o
obj-m += cxl_mem.o
cxl_mem-y := $(CXL_SRC)/mem.o $(CXL_SRC)/features.o
+cxl_mem-$(CONFIG_CXL_FWCTL) += $(CXL_SRC)/fwctl.o
cxl_mem-y += config_check.o
cxl_mem-y += cxl_mem_test.o
--
2.48.1
next prev parent reply other threads:[~2025-02-01 0:45 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-01 0:41 [PATCH v2 0/16] cxl: Add CXL feature commands support via fwctl Dave Jiang
2025-02-01 0:41 ` [PATCH v2 01/16] cxl: Refactor user ioctl command path from mds to mailbox Dave Jiang
2025-02-01 0:41 ` [PATCH v2 02/16] cxl: Enumerate feature commands Dave Jiang
2025-02-03 12:06 ` Jonathan Cameron
2025-02-03 23:23 ` Dave Jiang
2025-02-01 0:41 ` [PATCH v2 03/16] cxl: Add Get Supported Features command for kernel usage Dave Jiang
2025-02-03 12:19 ` Jonathan Cameron
2025-02-01 0:41 ` [PATCH v2 04/16] cxl/test: Add Get Supported Features mailbox command support Dave Jiang
2025-02-03 12:22 ` Jonathan Cameron
2025-02-01 0:41 ` [PATCH v2 05/16] cxl/mbox: Add GET_FEATURE mailbox command Dave Jiang
2025-02-01 0:41 ` [PATCH v2 06/16] cxl/mbox: Add SET_FEATURE " Dave Jiang
2025-02-03 12:27 ` Jonathan Cameron
2025-02-01 0:42 ` [PATCH v2 07/16] cxl: Setup exclusive CXL features that are reserved for the kernel Dave Jiang
2025-02-01 0:42 ` Dave Jiang [this message]
2025-02-01 1:04 ` [PATCH v2 08/16] cxl: Add FWCTL support to the CXL memdev driver Dave Jiang
2025-02-03 12:42 ` Jonathan Cameron
2025-02-03 14:25 ` Jason Gunthorpe
2025-02-03 16:22 ` Dave Jiang
2025-02-03 16:30 ` Jason Gunthorpe
2025-02-01 0:42 ` [PATCH v2 09/16] cxl: Add support for FWCTL get driver information callback Dave Jiang
2025-02-03 12:43 ` Jonathan Cameron
2025-02-01 0:42 ` [PATCH v2 10/16] cxl: Move cxl feature command structs to user header Dave Jiang
2025-02-01 0:42 ` [PATCH v2 11/16] cxl: Add support for fwctl RPC command to enable CXL feature commands Dave Jiang
2025-02-03 13:03 ` Jonathan Cameron
2025-02-01 0:42 ` [PATCH v2 12/16] cxl: Add support to handle user feature commands for get feature Dave Jiang
2025-02-01 0:42 ` [PATCH v2 13/16] cxl: Add support to handle user feature commands for set feature Dave Jiang
2025-02-01 0:42 ` [PATCH v2 14/16] cxl/test: Add Get Feature support to cxl_test Dave Jiang
2025-02-01 0:42 ` [PATCH v2 15/16] cxl/test: Add Set " Dave Jiang
2025-02-01 0:42 ` [PATCH v2 16/16] fwctl/cxl: Add documentation to FWCTL CXL Dave Jiang
2025-02-03 13:08 ` Jonathan Cameron
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