On 1/14/26 11:20 AM, Terry Bowman wrote:
> In preparation for CXL VH (Virtual Host) topology protocol error handling,
> add RAS capability registered mapping for all ports in a CXL VH topology.
> This includes the RAS capabilities of Switch Upstream Ports, Switch
> Downstream Ports, Host Bridge Ports ("upstream"), and Root Ports
> ("downstream")
>
> Update cxl_port_add_dport() to map the upstream RAS capability on first
> 'dport' attach, and downstream RAS capability on each 'dport' attach.
> Arrange for dport mappings to be released at del_dport() time.
>
> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> [djbw: reword changelog, fix devm handling]
drop the line above
DJ
> Co-developed-by: Dan Williams <dan.j.williams@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
>
> ---
>
> Changes in v13->v14:
> - Correct message spelling (Terry)
> ---
> drivers/cxl/core/port.c | 2 +-
> drivers/cxl/core/ras.c | 11 +++++++++++
> drivers/cxl/cxl.h | 2 ++
> drivers/cxl/cxlpci.h | 4 ++++
> drivers/cxl/port.c | 37 +++++++++++++++++++++++++++++++++++
> tools/testing/cxl/Kbuild | 1 +
> tools/testing/cxl/test/mock.c | 12 ++++++++++++
> 7 files changed, 68 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
> index 2184c20af011..2c4e28e7975c 100644
> --- a/drivers/cxl/core/port.c
> +++ b/drivers/cxl/core/port.c
> @@ -1451,7 +1451,7 @@ static void del_dport(struct cxl_dport *dport)
> {
> struct cxl_port *port = dport->port;
>
> - devm_release_action(&port->dev, unlink_dport, dport);
> + devres_release_group(&port->dev, dport);
> }
>
> static void del_dports(struct cxl_port *port)
> diff --git a/drivers/cxl/core/ras.c b/drivers/cxl/core/ras.c
> index 84abcf90fa99..76ac567724e3 100644
> --- a/drivers/cxl/core/ras.c
> +++ b/drivers/cxl/core/ras.c
> @@ -162,6 +162,17 @@ void devm_cxl_dport_ras_setup(struct cxl_dport *dport)
> }
> EXPORT_SYMBOL_NS_GPL(devm_cxl_dport_ras_setup, "CXL");
>
> +void devm_cxl_port_ras_setup(struct cxl_port *port)
> +{
> + struct cxl_register_map *map = &port->reg_map;
> +
> + map->host = &port->dev;
> + if (cxl_map_component_regs(map, &port->regs,
> + BIT(CXL_CM_CAP_CAP_ID_RAS)))
> + dev_dbg(&port->dev, "Failed to map RAS capability\n");
> +}
> +EXPORT_SYMBOL_NS_GPL(devm_cxl_port_ras_setup, "CXL");
> +
> void cxl_handle_cor_ras(struct device *dev, u64 serial, void __iomem *ras_base)
> {
> void __iomem *addr;
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 46491046f101..805923693707 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -607,6 +607,7 @@ struct cxl_dax_region {
> * @parent_dport: dport that points to this port in the parent
> * @decoder_ida: allocator for decoder ids
> * @reg_map: component and ras register mapping parameters
> + * @regs: mapped component registers
> * @nr_dports: number of entries in @dports
> * @hdm_end: track last allocated HDM decoder instance for allocation ordering
> * @commit_end: cursor to track highest committed decoder for commit ordering
> @@ -628,6 +629,7 @@ struct cxl_port {
> struct cxl_dport *parent_dport;
> struct ida decoder_ida;
> struct cxl_register_map reg_map;
> + struct cxl_component_regs regs;
> int nr_dports;
> int hdm_end;
> int commit_end;
> diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
> index e41bb93d583a..ef4496b4e55e 100644
> --- a/drivers/cxl/cxlpci.h
> +++ b/drivers/cxl/cxlpci.h
> @@ -82,6 +82,7 @@ void cxl_cor_error_detected(struct pci_dev *pdev);
> pci_ers_result_t cxl_error_detected(struct pci_dev *pdev,
> pci_channel_state_t state);
> void devm_cxl_dport_ras_setup(struct cxl_dport *dport);
> +void devm_cxl_port_ras_setup(struct cxl_port *port);
> #else
> static inline void cxl_cor_error_detected(struct pci_dev *pdev) { }
>
> @@ -93,6 +94,9 @@ static inline pci_ers_result_t cxl_error_detected(struct pci_dev *pdev,
> static inline void devm_cxl_dport_ras_setup(struct cxl_dport *dport)
> {
> }
> +static inline void devm_cxl_port_ras_setup(struct cxl_port *port)
> +{
> +}
> #endif
>
> #endif /* __CXL_PCI_H__ */
> diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
> index 8f8fc98c1428..0d6e010e21ca 100644
> --- a/drivers/cxl/port.c
> +++ b/drivers/cxl/port.c
> @@ -176,11 +176,29 @@ static struct cxl_port *cxl_port_devres_group(struct cxl_port *port)
> DEFINE_FREE(cxl_port_group_free, struct cxl_port *,
> if (!IS_ERR_OR_NULL(_T)) devres_release_group(&(_T)->dev, _T))
>
> +static struct cxl_dport *cxl_dport_devres_group(struct cxl_dport *dport)
> +{
> + if (!devres_open_group(&dport->port->dev, dport, GFP_KERNEL))
> + return ERR_PTR(-ENOMEM);
> + return dport;
> +}
> +DEFINE_FREE(cxl_dport_group_free, struct cxl_dport *,
> + if (!IS_ERR_OR_NULL(_T)) devres_release_group(&(_T)->port->dev, _T))
> +
> static void cxl_port_group_close(struct cxl_port *port)
> {
> devres_remove_group(&port->dev, port);
> }
>
> +/*
> + * Unlike the port group, that just facilitates unwind of setup failures, the
> + * dport group needs to stay live for del_dport() to reference.
> + */
> +static void cxl_dport_group_close(struct cxl_dport *dport)
> +{
> + devres_close_group(&dport->port->dev, dport);
> +}
> +
> static struct cxl_dport *cxl_port_add_dport(struct cxl_port *port,
> struct device *dport_dev)
> {
> @@ -209,6 +227,13 @@ static struct cxl_dport *cxl_port_add_dport(struct cxl_port *port,
> rc = devm_cxl_switch_port_decoders_setup(port);
> if (rc)
> return ERR_PTR(rc);
> +
> + /*
> + * RAS setup is optional, either driver operation can continue
> + * on failure, or the device does not implement RAS registers.
> + */
> + devm_cxl_port_ras_setup(port);
> +
> /*
> * Note, when nr_dports returns to zero the port is unregistered
> * and triggers cleanup. I.e. no need for open-coded release
> @@ -220,12 +245,24 @@ static struct cxl_dport *cxl_port_add_dport(struct cxl_port *port,
> if (IS_ERR(new_dport))
> return new_dport;
>
> + /*
> + * Establish a group for all dport resources that need to be released
> + * when the dport is deleted.
> + */
> + struct cxl_dport *dport_group __free(cxl_dport_group_free) =
> + cxl_dport_devres_group(new_dport);
> + if (IS_ERR(dport_group))
> + return ERR_CAST(dport_group);
> +
> rc = cxl_dport_autoremove(new_dport);
> if (rc)
> return ERR_PTR(rc);
>
> + devm_cxl_dport_ras_setup(new_dport);
> +
> cxl_switch_parse_cdat(new_dport);
>
> + cxl_dport_group_close(no_free_ptr(dport_group));
> cxl_port_group_close(no_free_ptr(port_group));
>
> dev_dbg(&port->dev, "dport[%d] id:%d dport_dev: %s added\n",
> diff --git a/tools/testing/cxl/Kbuild b/tools/testing/cxl/Kbuild
> index 7250bedf0448..6c516019600e 100644
> --- a/tools/testing/cxl/Kbuild
> +++ b/tools/testing/cxl/Kbuild
> @@ -13,6 +13,7 @@ ldflags-y += --wrap=devm_cxl_endpoint_decoders_setup
> ldflags-y += --wrap=hmat_get_extended_linear_cache_size
> ldflags-y += --wrap=cxl_add_dport_by_dev
> ldflags-y += --wrap=devm_cxl_switch_port_decoders_setup
> +ldflags-y += --wrap=devm_cxl_port_ras_setup
>
> DRIVERS := ../../../drivers
> CXL_SRC := $(DRIVERS)/cxl
> diff --git a/tools/testing/cxl/test/mock.c b/tools/testing/cxl/test/mock.c
> index 8883357ee50d..a0b87bbb2f75 100644
> --- a/tools/testing/cxl/test/mock.c
> +++ b/tools/testing/cxl/test/mock.c
> @@ -246,6 +246,18 @@ void __wrap_devm_cxl_dport_ras_setup(struct cxl_dport *dport)
> }
> EXPORT_SYMBOL_NS_GPL(__wrap_devm_cxl_dport_ras_setup, "CXL");
>
> +void __wrap_devm_cxl_port_ras_setup(struct cxl_port *port)
> +{
> + int index;
> + struct cxl_mock_ops *ops = get_cxl_mock_ops(&index);
> +
> + if (!ops || !ops->is_mock_port(port->uport_dev))
> + devm_cxl_port_ras_setup(port);
> +
> + put_cxl_mock_ops(index);
> +}
> +EXPORT_SYMBOL_NS_GPL(__wrap_devm_cxl_port_ras_setup, "CXL");
> +
> struct cxl_dport *__wrap_cxl_add_dport_by_dev(struct cxl_port *port,
> struct device *dport_dev)
> {