Merge tag 'for-linus-fwctl' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull fwctl subsystem from Jason Gunthorpe:
 "fwctl is a new subsystem intended to bring some common rules and order
  to the growing pattern of exposing a secure FW interface directly to
  userspace.

  Unlike existing places like RDMA/DRM/VFIO/uacce that are exposing a
  device for datapath operations fwctl is focused on debugging,
  configuration and provisioning of the device. It will not have the
  necessary features like interrupt delivery to support a datapath.

  This concept is similar to the long standing practice in the "HW" RAID
  space of having a device specific misc device to manage the RAID
  controller FW. fwctl generalizes this notion of a companion debug and
  management interface that goes along with a dataplane implemented in
  an appropriate subsystem.

  There have been three LWN articles written discussing various aspects
  of this:

	https://lwn.net/Articles/955001/
	https://lwn.net/Articles/969383/
	https://lwn.net/Articles/990802/

  This includes three drivers to launch the subsystem:

   - CXL provides a vendor scheme for executing commands and a way to
     learn the 'command effects' (ie the security properties) of such
     commands. The fwctl driver allows access to these mechanism within
     the fwctl security model

   - mlx5 is family of networking products, the driver supports all
     current Mellanox HW still receiving FW feature updates. This
     includes RDMA multiprotocol NICs like ConnectX and the Bluefield
     family of Smart NICs.

   - AMD/Pensando Distributed Services card is a multi protocol Smart
     NIC with a multi PCI function design. fwctl works on the management
     PCI function following a 'command effects' model similar to CXL"

* tag 'for-linus-fwctl' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (30 commits)
  pds_fwctl: add Documentation entries
  pds_fwctl: add rpc and query support
  pds_fwctl: initial driver framework
  pds_core: add new fwctl auxiliary_device
  pds_core: specify auxiliary_device to be created
  pds_core: make pdsc_auxbus_dev_del() void
  cxl: Fixup kdoc issues for include/cxl/features.h
  fwctl/cxl: Add documentation to FWCTL CXL
  cxl/test: Add Set Feature support to cxl_test
  cxl/test: Add Get Feature support to cxl_test
  cxl: Add support to handle user feature commands for set feature
  cxl: Add support to handle user feature commands for get feature
  cxl: Add support for fwctl RPC command to enable CXL feature commands
  cxl: Move cxl feature command structs to user header
  cxl: Add FWCTL support to CXL
  mlx5: Create an auxiliary device for fwctl_mlx5
  fwctl/mlx5: Support for communicating with mlx5 fw
  fwctl: Add documentation
  fwctl: FWCTL_RPC to execute a Remote Procedure Call to device firmware
  taint: Add TAINT_FWCTL
  ...

6 files changed, 66 insertions, 34 deletions

diff --git a/drivers/net/ethernet/amd/pds_core/auxbus.c b/drivers/net/ethernet/amd/pds_core/auxbus.c
index 2babea110991..eeb72b1809ea 100644
--- a/drivers/net/ethernet/amd/pds_core/auxbus.c
+++ b/drivers/net/ethernet/amd/pds_core/auxbus.c
@@ -175,34 +175,32 @@ static struct pds_auxiliary_dev *pdsc_auxbus_dev_register(struct pdsc *cf,
 	return padev;
 }
 
-int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf)
+void pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf,
+			 struct pds_auxiliary_dev **pd_ptr)
 {
 	struct pds_auxiliary_dev *padev;
-	int err = 0;
 
-	if (!cf)
-		return -ENODEV;
+	if (!*pd_ptr)
+		return;
 
 	mutex_lock(&pf->config_lock);
 
-	padev = pf->vfs[cf->vf_id].padev;
-	if (padev) {
-		pds_client_unregister(pf, padev->client_id);
-		auxiliary_device_delete(&padev->aux_dev);
-		auxiliary_device_uninit(&padev->aux_dev);
-		padev->client_id = 0;
-	}
-	pf->vfs[cf->vf_id].padev = NULL;
+	padev = *pd_ptr;
+	pds_client_unregister(pf, padev->client_id);
+	auxiliary_device_delete(&padev->aux_dev);
+	auxiliary_device_uninit(&padev->aux_dev);
+	padev->client_id = 0;
+	*pd_ptr = NULL;
 
 	mutex_unlock(&pf->config_lock);
-	return err;
 }
 
-int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
+int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf,
+			enum pds_core_vif_types vt,
+			struct pds_auxiliary_dev **pd_ptr)
 {
 	struct pds_auxiliary_dev *padev;
 	char devname[PDS_DEVNAME_LEN];
-	enum pds_core_vif_types vt;
 	unsigned long mask;
 	u16 vt_support;
 	int client_id;
@@ -211,6 +209,9 @@ int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
 	if (!cf)
 		return -ENODEV;
 
+	if (vt >= PDS_DEV_TYPE_MAX)
+		return -EINVAL;
+
 	mutex_lock(&pf->config_lock);
 
 	mask = BIT_ULL(PDSC_S_FW_DEAD) |
@@ -222,17 +223,10 @@ int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
 		goto out_unlock;
 	}
 
-	/* We only support vDPA so far, so it is the only one to
-	 * be verified that it is available in the Core device and
-	 * enabled in the devlink param.  In the future this might
-	 * become a loop for several VIF types.
-	 */
-
 	/* Verify that the type is supported and enabled.  It is not
-	 * an error if there is no auxbus device support for this
-	 * VF, it just means something else needs to happen with it.
+	 * an error if the firmware doesn't support the feature, the
+	 * driver just won't set up an auxiliary_device for it.
 	 */
-	vt = PDS_DEV_TYPE_VDPA;
 	vt_support = !!le16_to_cpu(pf->dev_ident.vif_types[vt]);
 	if (!(vt_support &&
 	      pf->viftype_status[vt].supported &&
@@ -258,7 +252,7 @@ int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
 		err = PTR_ERR(padev);
 		goto out_unlock;
 	}
-	pf->vfs[cf->vf_id].padev = padev;
+	*pd_ptr = padev;
 
 out_unlock:
 	mutex_unlock(&pf->config_lock);
diff --git a/drivers/net/ethernet/amd/pds_core/core.c b/drivers/net/ethernet/amd/pds_core/core.c
index 536635e57727..1eb0d92786f7 100644
--- a/drivers/net/ethernet/amd/pds_core/core.c
+++ b/drivers/net/ethernet/amd/pds_core/core.c
@@ -402,6 +402,9 @@ err_out_uninit:
 }
 
 static struct pdsc_viftype pdsc_viftype_defaults[] = {
+	[PDS_DEV_TYPE_FWCTL] = { .name = PDS_DEV_TYPE_FWCTL_STR,
+				 .vif_id = PDS_DEV_TYPE_FWCTL,
+				 .dl_id = -1 },
 	[PDS_DEV_TYPE_VDPA] = { .name = PDS_DEV_TYPE_VDPA_STR,
 				.vif_id = PDS_DEV_TYPE_VDPA,
 				.dl_id = DEVLINK_PARAM_GENERIC_ID_ENABLE_VNET },
@@ -428,6 +431,10 @@ static int pdsc_viftypes_init(struct pdsc *pdsc)
 
 		/* See what the Core device has for support */
 		vt_support = !!le16_to_cpu(pdsc->dev_ident.vif_types[vt]);
+
+		if (vt == PDS_DEV_TYPE_FWCTL)
+			pdsc->viftype_status[vt].enabled = true;
+
 		dev_dbg(pdsc->dev, "VIF %s is %ssupported\n",
 			pdsc->viftype_status[vt].name,
 			vt_support ? "" : "not ");
diff --git a/drivers/net/ethernet/amd/pds_core/core.h b/drivers/net/ethernet/amd/pds_core/core.h
index 14522d6d5f86..0bf320c43083 100644
--- a/drivers/net/ethernet/amd/pds_core/core.h
+++ b/drivers/net/ethernet/amd/pds_core/core.h
@@ -156,6 +156,7 @@ struct pdsc {
 	struct dentry *dentry;
 	struct device *dev;
 	struct pdsc_dev_bar bars[PDS_CORE_BARS_MAX];
+	struct pds_auxiliary_dev *padev;
 	struct pdsc_vf *vfs;
 	int num_vfs;
 	int vf_id;
@@ -303,8 +304,11 @@ void pdsc_health_thread(struct work_struct *work);
 int pdsc_register_notify(struct notifier_block *nb);
 void pdsc_unregister_notify(struct notifier_block *nb);
 void pdsc_notify(unsigned long event, void *data);
-int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf);
-int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf);
+int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf,
+			enum pds_core_vif_types vt,
+			struct pds_auxiliary_dev **pd_ptr);
+void pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf,
+			 struct pds_auxiliary_dev **pd_ptr);
 
 void pdsc_process_adminq(struct pdsc_qcq *qcq);
 void pdsc_work_thread(struct work_struct *work);
diff --git a/drivers/net/ethernet/amd/pds_core/devlink.c b/drivers/net/ethernet/amd/pds_core/devlink.c
index 44971e71991f..c5c787df61a4 100644
--- a/drivers/net/ethernet/amd/pds_core/devlink.c
+++ b/drivers/net/ethernet/amd/pds_core/devlink.c
@@ -56,8 +56,11 @@ int pdsc_dl_enable_set(struct devlink *dl, u32 id,
 	for (vf_id = 0; vf_id < pdsc->num_vfs; vf_id++) {
 		struct pdsc *vf = pdsc->vfs[vf_id].vf;
 
-		err = ctx->val.vbool ? pdsc_auxbus_dev_add(vf, pdsc) :
-				       pdsc_auxbus_dev_del(vf, pdsc);
+		if (ctx->val.vbool)
+			err = pdsc_auxbus_dev_add(vf, pdsc, vt_entry->vif_id,
+						  &pdsc->vfs[vf_id].padev);
+		else
+			pdsc_auxbus_dev_del(vf, pdsc, &pdsc->vfs[vf_id].padev);
 	}
 
 	return err;
diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c
index 660268ff9562..4843f9249a31 100644
--- a/drivers/net/ethernet/amd/pds_core/main.c
+++ b/drivers/net/ethernet/amd/pds_core/main.c
@@ -190,7 +190,8 @@ static int pdsc_init_vf(struct pdsc *vf)
 	devl_unlock(dl);
 
 	pf->vfs[vf->vf_id].vf = vf;
-	err = pdsc_auxbus_dev_add(vf, pf);
+	err = pdsc_auxbus_dev_add(vf, pf, PDS_DEV_TYPE_VDPA,
+				  &pf->vfs[vf->vf_id].padev);
 	if (err) {
 		devl_lock(dl);
 		devl_unregister(dl);
@@ -264,6 +265,10 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 
 	mutex_unlock(&pdsc->config_lock);
 
+	err = pdsc_auxbus_dev_add(pdsc, pdsc, PDS_DEV_TYPE_FWCTL, &pdsc->padev);
+	if (err)
+		goto err_out_stop;
+
 	dl = priv_to_devlink(pdsc);
 	devl_lock(dl);
 	err = devl_params_register(dl, pdsc_dl_params,
@@ -272,7 +277,7 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 		devl_unlock(dl);
 		dev_warn(pdsc->dev, "Failed to register devlink params: %pe\n",
 			 ERR_PTR(err));
-		goto err_out_stop;
+		goto err_out_del_dev;
 	}
 
 	hr = devl_health_reporter_create(dl, &pdsc_fw_reporter_ops, 0, pdsc);
@@ -295,6 +300,8 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 err_out_unreg_params:
 	devlink_params_unregister(dl, pdsc_dl_params,
 				  ARRAY_SIZE(pdsc_dl_params));
+err_out_del_dev:
+	pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev);
 err_out_stop:
 	pdsc_stop(pdsc);
 err_out_teardown:
@@ -417,7 +424,7 @@ static void pdsc_remove(struct pci_dev *pdev)
 
 		pf = pdsc_get_pf_struct(pdsc->pdev);
 		if (!IS_ERR(pf)) {
-			pdsc_auxbus_dev_del(pdsc, pf);
+			pdsc_auxbus_dev_del(pdsc, pf, &pf->vfs[pdsc->vf_id].padev);
 			pf->vfs[pdsc->vf_id].vf = NULL;
 		}
 	} else {
@@ -426,6 +433,7 @@ static void pdsc_remove(struct pci_dev *pdev)
 		 * shut themselves down.
 		 */
 		pdsc_sriov_configure(pdev, 0);
+		pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev);
 
 		timer_shutdown_sync(&pdsc->wdtimer);
 		if (pdsc->wq)
@@ -482,7 +490,10 @@ static void pdsc_reset_prepare(struct pci_dev *pdev)
 
 		pf = pdsc_get_pf_struct(pdsc->pdev);
 		if (!IS_ERR(pf))
-			pdsc_auxbus_dev_del(pdsc, pf);
+			pdsc_auxbus_dev_del(pdsc, pf,
+					    &pf->vfs[pdsc->vf_id].padev);
+	} else {
+		pdsc_auxbus_dev_del(pdsc, pdsc, &pdsc->padev);
 	}
 
 	pdsc_unmap_bars(pdsc);
@@ -527,7 +538,11 @@ static void pdsc_reset_done(struct pci_dev *pdev)
 
 		pf = pdsc_get_pf_struct(pdsc->pdev);
 		if (!IS_ERR(pf))
-			pdsc_auxbus_dev_add(pdsc, pf);
+			pdsc_auxbus_dev_add(pdsc, pf, PDS_DEV_TYPE_VDPA,
+					    &pf->vfs[pdsc->vf_id].padev);
+	} else {
+		pdsc_auxbus_dev_add(pdsc, pdsc, PDS_DEV_TYPE_FWCTL,
+				    &pdsc->padev);
 	}
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
index 9a79674d27f1..891bbbbfbbf1 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/dev.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/dev.c
@@ -228,8 +228,15 @@ enum {
 	MLX5_INTERFACE_PROTOCOL_VNET,
 
 	MLX5_INTERFACE_PROTOCOL_DPLL,
+	MLX5_INTERFACE_PROTOCOL_FWCTL,
 };
 
+static bool is_fwctl_supported(struct mlx5_core_dev *dev)
+{
+	/* fwctl is most useful on PFs, prevent fwctl on SFs for now */
+	return MLX5_CAP_GEN(dev, uctx_cap) && !mlx5_core_is_sf(dev);
+}
+
 static const struct mlx5_adev_device {
 	const char *suffix;
 	bool (*is_supported)(struct mlx5_core_dev *dev);
@@ -252,6 +259,8 @@ static const struct mlx5_adev_device {
 					   .is_supported = &is_mp_supported },
 	[MLX5_INTERFACE_PROTOCOL_DPLL] = { .suffix = "dpll",
 					   .is_supported = &is_dpll_supported },
+	[MLX5_INTERFACE_PROTOCOL_FWCTL] = { .suffix = "fwctl",
+					    .is_supported = &is_fwctl_supported },
 };
 
 int mlx5_adev_idx_alloc(void)