--- v26
+++ v22
@@ -1,35 +1,239 @@
From: Alejandro Lucero <alucerop@amd.com>
-Use cxl API for creating a cxl memory device using the type2
-cxl_dev_state struct.
+Add CXL initialization based on new CXL API for accel drivers and make
+it dependent on kernel CXL configuration.
Signed-off-by: Alejandro Lucero <alucerop@amd.com>
-Reviewed-by: Martin Habets <habetsm.xilinx@gmail.com>
-Reviewed-by: Fan Ni <fan.ni@samsung.com>
+Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com>
-Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
+Reviewed-by: Alison Schofield <alison.schofield@intel.com>
+Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
---
- drivers/net/ethernet/sfc/efx_cxl.c | 6 ++++++
- 1 file changed, 6 insertions(+)
-
+ drivers/net/ethernet/sfc/Kconfig | 9 +++++
+ drivers/net/ethernet/sfc/Makefile | 1 +
+ drivers/net/ethernet/sfc/efx.c | 15 ++++++-
+ drivers/net/ethernet/sfc/efx_cxl.c | 56 +++++++++++++++++++++++++++
+ drivers/net/ethernet/sfc/efx_cxl.h | 40 +++++++++++++++++++
+ drivers/net/ethernet/sfc/net_driver.h | 10 +++++
+ 6 files changed, 130 insertions(+), 1 deletion(-)
+ create mode 100644 drivers/net/ethernet/sfc/efx_cxl.c
+ create mode 100644 drivers/net/ethernet/sfc/efx_cxl.h
+
+diff --git a/drivers/net/ethernet/sfc/Kconfig b/drivers/net/ethernet/sfc/Kconfig
+index c4c43434f314..979f2801e2a8 100644
+--- a/drivers/net/ethernet/sfc/Kconfig
++++ b/drivers/net/ethernet/sfc/Kconfig
+@@ -66,6 +66,15 @@ config SFC_MCDI_LOGGING
+ Driver-Interface) commands and responses, allowing debugging of
+ driver/firmware interaction. The tracing is actually enabled by
+ a sysfs file 'mcdi_logging' under the PCI device.
++config SFC_CXL
++ bool "Solarflare SFC9100-family CXL support"
++ depends on SFC && CXL_BUS >= SFC
++ default SFC
++ help
++ This enables SFC CXL support if the kernel is configuring CXL for
++ using CTPIO with CXL.mem. The SFC device with CXL support and
++ with a CXL-aware firmware can be used for minimizing latencies
++ when sending through CTPIO.
+
+ source "drivers/net/ethernet/sfc/falcon/Kconfig"
+ source "drivers/net/ethernet/sfc/siena/Kconfig"
+diff --git a/drivers/net/ethernet/sfc/Makefile b/drivers/net/ethernet/sfc/Makefile
+index d99039ec468d..bb0f1891cde6 100644
+--- a/drivers/net/ethernet/sfc/Makefile
++++ b/drivers/net/ethernet/sfc/Makefile
+@@ -13,6 +13,7 @@ sfc-$(CONFIG_SFC_SRIOV) += sriov.o ef10_sriov.o ef100_sriov.o ef100_rep.o \
+ mae.o tc.o tc_bindings.o tc_counters.o \
+ tc_encap_actions.o tc_conntrack.o
+
++sfc-$(CONFIG_SFC_CXL) += efx_cxl.o
+ obj-$(CONFIG_SFC) += sfc.o
+
+ obj-$(CONFIG_SFC_FALCON) += falcon/
+diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
+index 112e55b98ed3..537668278375 100644
+--- a/drivers/net/ethernet/sfc/efx.c
++++ b/drivers/net/ethernet/sfc/efx.c
+@@ -34,6 +34,7 @@
+ #include "selftest.h"
+ #include "sriov.h"
+ #include "efx_devlink.h"
++#include "efx_cxl.h"
+
+ #include "mcdi_port_common.h"
+ #include "mcdi_pcol.h"
+@@ -981,12 +982,15 @@ static void efx_pci_remove(struct pci_dev *pci_dev)
+ efx_pci_remove_main(efx);
+
+ efx_fini_io(efx);
++
++ probe_data = container_of(efx, struct efx_probe_data, efx);
++ efx_cxl_exit(probe_data);
++
+ pci_dbg(efx->pci_dev, "shutdown successful\n");
+
+ efx_fini_devlink_and_unlock(efx);
+ efx_fini_struct(efx);
+ free_netdev(efx->net_dev);
+- probe_data = container_of(efx, struct efx_probe_data, efx);
+ kfree(probe_data);
+ };
+
+@@ -1190,6 +1194,15 @@ static int efx_pci_probe(struct pci_dev *pci_dev,
+ if (rc)
+ goto fail2;
+
++ /* A successful cxl initialization implies a CXL region created to be
++ * used for PIO buffers. If there is no CXL support, or initialization
++ * fails, efx_cxl_pio_initialised will be false and legacy PIO buffers
++ * defined at specific PCI BAR regions will be used.
++ */
++ rc = efx_cxl_init(probe_data);
++ if (rc)
++ pci_err(pci_dev, "CXL initialization failed with error %d\n", rc);
++
+ rc = efx_pci_probe_post_io(efx);
+ if (rc) {
+ /* On failure, retry once immediately.
diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
-index 4d55c08cf2a1..7d8a6c2133c8 100644
---- a/drivers/net/ethernet/sfc/efx_cxl.c
+new file mode 100644
+index 000000000000..8e0481d8dced
+--- /dev/null
+++ b/drivers/net/ethernet/sfc/efx_cxl.c
-@@ -75,6 +75,12 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
- return -ENODEV;
- }
-
-+ cxl->cxlmd = devm_cxl_add_memdev(&cxl->cxlds, NULL);
-+ if (IS_ERR(cxl->cxlmd)) {
-+ pci_err(pci_dev, "CXL accel memdev creation failed\n");
-+ return PTR_ERR(cxl->cxlmd);
+@@ -0,0 +1,56 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/****************************************************************************
++ *
++ * Driver for AMD network controllers and boards
++ * Copyright (C) 2025, Advanced Micro Devices, Inc.
++ */
++
++#include <linux/pci.h>
++
++#include "net_driver.h"
++#include "efx_cxl.h"
++
++#define EFX_CTPIO_BUFFER_SIZE SZ_256M
++
++int efx_cxl_init(struct efx_probe_data *probe_data)
++{
++ struct efx_nic *efx = &probe_data->efx;
++ struct pci_dev *pci_dev = efx->pci_dev;
++ struct efx_cxl *cxl;
++ u16 dvsec;
++
++ probe_data->cxl_pio_initialised = false;
++
++ /* Is the device configured with and using CXL? */
++ if (!pcie_is_cxl(pci_dev))
++ return 0;
++
++ dvsec = pci_find_dvsec_capability(pci_dev, PCI_VENDOR_ID_CXL,
++ PCI_DVSEC_CXL_DEVICE);
++ if (!dvsec) {
++ pci_err(pci_dev, "CXL_DVSEC_PCIE_DEVICE capability not found\n");
++ return 0;
+ }
+
- probe_data->cxl = cxl;
-
- return 0;
++ pci_dbg(pci_dev, "CXL_DVSEC_PCIE_DEVICE capability found\n");
++
++ /* Create a cxl_dev_state embedded in the cxl struct using cxl core api
++ * specifying no mbox available.
++ */
++ cxl = devm_cxl_dev_state_create(&pci_dev->dev, CXL_DEVTYPE_DEVMEM,
++ pci_dev->dev.id, dvsec, struct efx_cxl,
++ cxlds, false);
++
++ if (!cxl)
++ return -ENOMEM;
++
++ probe_data->cxl = cxl;
++
++ return 0;
++}
++
++void efx_cxl_exit(struct efx_probe_data *probe_data)
++{
++}
++
++MODULE_IMPORT_NS("CXL");
+diff --git a/drivers/net/ethernet/sfc/efx_cxl.h b/drivers/net/ethernet/sfc/efx_cxl.h
+new file mode 100644
+index 000000000000..961639cef692
+--- /dev/null
++++ b/drivers/net/ethernet/sfc/efx_cxl.h
+@@ -0,0 +1,40 @@
++/* SPDX-License-Identifier: GPL-2.0-only */
++/****************************************************************************
++ * Driver for AMD network controllers and boards
++ * Copyright (C) 2025, Advanced Micro Devices, Inc.
++ *
++ * This program is free software; you can redistribute it and/or modify it
++ * under the terms of the GNU General Public License version 2 as published
++ * by the Free Software Foundation, incorporated herein by reference.
++ */
++
++#ifndef EFX_CXL_H
++#define EFX_CXL_H
++
++#ifdef CONFIG_SFC_CXL
++
++#include <cxl/cxl.h>
++
++struct cxl_root_decoder;
++struct cxl_port;
++struct cxl_endpoint_decoder;
++struct cxl_region;
++struct efx_probe_data;
++
++struct efx_cxl {
++ struct cxl_dev_state cxlds;
++ struct cxl_memdev *cxlmd;
++ struct cxl_root_decoder *cxlrd;
++ struct cxl_port *endpoint;
++ struct cxl_endpoint_decoder *cxled;
++ struct cxl_region *efx_region;
++ void __iomem *ctpio_cxl;
++};
++
++int efx_cxl_init(struct efx_probe_data *probe_data);
++void efx_cxl_exit(struct efx_probe_data *probe_data);
++#else
++static inline int efx_cxl_init(struct efx_probe_data *probe_data) { return 0; }
++static inline void efx_cxl_exit(struct efx_probe_data *probe_data) {}
++#endif
++#endif
+diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
+index b98c259f672d..3964b2c56609 100644
+--- a/drivers/net/ethernet/sfc/net_driver.h
++++ b/drivers/net/ethernet/sfc/net_driver.h
+@@ -1197,14 +1197,24 @@ struct efx_nic {
+ atomic_t n_rx_noskb_drops;
+ };
+
++#ifdef CONFIG_SFC_CXL
++struct efx_cxl;
++#endif
++
+ /**
+ * struct efx_probe_data - State after hardware probe
+ * @pci_dev: The PCI device
+ * @efx: Efx NIC details
++ * @cxl: details of related cxl objects
++ * @cxl_pio_initialised: cxl initialization outcome.
+ */
+ struct efx_probe_data {
+ struct pci_dev *pci_dev;
+ struct efx_nic efx;
++#ifdef CONFIG_SFC_CXL
++ struct efx_cxl *cxl;
++ bool cxl_pio_initialised;
++#endif
+ };
+
+ static inline struct efx_nic *efx_netdev_priv(struct net_device *dev)
--
2.34.1