On 1/15/2026 10:18 AM, Jonathan Cameron wrote:
> On Wed, 14 Jan 2026 12:20:55 -0600
> Terry Bowman <terry.bowman@amd.com> wrote:
>
>> CXL protocol errors are not enabled for all CXL devices after boot. These
>> must be enabled inorder to process CXL protocol errors.
>>
>> Introduce cxl_unmask_proto_interrupts() to call pci_aer_unmask_internal_errors().
>> pci_aer_unmask_internal_errors() expects the pdev->aer_cap is initialized.
>> But, dev->aer_cap is not initialized for CXL Upstream Switch Ports and CXL
>> Downstream Switch Ports. Initialize the dev->aer_cap if necessary. Enable AER
>> correctable internal errors and uncorrectable internal errors for all CXL
>> devices.
>>
>> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
>> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>> Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com>
>>
>
> A question inline.
>
>> ---
>>
>> Changes in v13->v14:
>> - Update commit title's prefix (Bjorn)
>>
>> Changes in v12->v13:
>> - Add dev and dev_is_pci() NULL checks in cxl_unmask_proto_interrupts() (Terry)
>> - Add Dave Jiang's and Ben's review-by
>>
>> Changes in v11->v12:
>> - None
>>
>> Changes in v10->v11:
>> - Added check for valid PCI devices in is_cxl_error() (Terry)
>> - Removed check for RCiEP in cxl_handle_proto_err() and
>> cxl_report_error_detected() (Terry)
>> ---
>> drivers/cxl/core/port.c | 2 ++
>> drivers/cxl/core/ras.c | 22 ++++++++++++++++++++++
>> drivers/cxl/cxlpci.h | 4 ++++
>> 3 files changed, 28 insertions(+)
>>
>> diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
>> index 0bec10be5d56..588801c5d406 100644
>> --- a/drivers/cxl/core/port.c
>> +++ b/drivers/cxl/core/port.c
>> @@ -1828,6 +1828,8 @@ int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd)
>>
>> rc = cxl_add_ep(dport, &cxlmd->dev);
>>
>> + cxl_unmask_proto_interrupts(cxlmd->cxlds->dev);
>> +
>> /*
>> * If the endpoint already exists in the port's list,
>> * that's ok, it was added on a previous pass.
>> diff --git a/drivers/cxl/core/ras.c b/drivers/cxl/core/ras.c
>> index 427009a8a78a..e299eb50fbe4 100644
>> --- a/drivers/cxl/core/ras.c
>> +++ b/drivers/cxl/core/ras.c
>> @@ -117,6 +117,24 @@ static void cxl_cper_prot_err_work_fn(struct work_struct *work)
>> }
>> static DECLARE_WORK(cxl_cper_prot_err_work, cxl_cper_prot_err_work_fn);
>>
>> +void cxl_unmask_proto_interrupts(struct device *dev)
>> +{
>> + if (!dev || !dev_is_pci(dev))
>> + return;
>> +
>> + struct pci_dev *pdev __free(pci_dev_put) = pci_dev_get(to_pci_dev(dev));
>> +
>> + if (!pdev->aer_cap) {
>
> Add a comment to say why this might not be set. How did we get here
> with out calling pci_aer_init()?
>
I borrowed this from the AER driver. cxl/core/ras.c and pci_dev::aer_cap are
both gated by CONFIG_PCIEAER making the only explanation for !pdev->aer_cap
to be caused by a missing AER capability. The CXL device is broken if this
happens.
-Terry
>> + pdev->aer_cap = pci_find_ext_capability(pdev,
>> + PCI_EXT_CAP_ID_ERR);
>> + if (!pdev->aer_cap)
>> + return;
>> + }
>> +
>> + pci_aer_unmask_internal_errors(pdev);
>> +}
>> +EXPORT_SYMBOL_NS_GPL(cxl_unmask_proto_interrupts, "CXL");
>> +
>> static void cxl_dport_map_ras(struct cxl_dport *dport)
>> {
>> struct cxl_register_map *map = &dport->reg_map;
>> @@ -127,6 +145,8 @@ static void cxl_dport_map_ras(struct cxl_dport *dport)
>> else if (cxl_map_component_regs(map, &dport->regs.component,
>> BIT(CXL_CM_CAP_CAP_ID_RAS)))
>> dev_dbg(dev, "Failed to map RAS capability.\n");
>> +
>> + cxl_unmask_proto_interrupts(dev);
>> }
>>
>> /**
>> @@ -159,6 +179,8 @@ void devm_cxl_port_ras_setup(struct cxl_port *port)
>> 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");
>> +
>> + cxl_unmask_proto_interrupts(port->uport_dev);
>> }
>> EXPORT_SYMBOL_NS_GPL(devm_cxl_port_ras_setup, "CXL");
>>
>> diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
>> index 3d70f9b4a193..0c915c0bdfac 100644
>> --- a/drivers/cxl/cxlpci.h
>> +++ b/drivers/cxl/cxlpci.h
>> @@ -89,6 +89,7 @@ void __cxl_uport_init_ras_reporting(struct cxl_port *port,
>> int __cxl_await_media_ready(struct cxl_dev_state *cxlds);
>> resource_size_t __cxl_rcd_component_reg_phys(struct device *dev,
>> struct cxl_dport *dport);
>> +void cxl_unmask_proto_interrupts(struct device *dev);
>> #else
>> static inline void cxl_pci_cor_error_detected(struct pci_dev *pdev)
>> {
>> @@ -104,6 +105,9 @@ static inline void devm_cxl_dport_ras_setup(struct cxl_dport *dport)
>> static inline void devm_cxl_port_ras_setup(struct cxl_port *port)
>> {
>> }
>> +static inline void cxl_unmask_proto_interrupts(struct device *dev)
>> +{
>> +}
>> #endif
>>
>> int cxl_port_setup_regs(struct cxl_port *port,
>