Re: [PATCH v3 04/20] cxl: move pci generic code

Dave Jiang
2024-09-11T23:55:02Z

On 9/7/24 1:18 AM, alejandro.lucero-palau@amd.com wrote:
> From: Alejandro Lucero <alucerop@amd.com>
>
> Inside cxl/core/pci.c there are helpers for CXL PCIe initialization
> meanwhile cxl/pci.c implements the functionality for a Type3 device
> initialization.
>
> Move those functions required also for Type2 initialization to
> cxl/core/pci.c with a specific function using that moved code added in
> a following patch.

Please consider rephrasing as:

Move helper functions from cxl/pci.c to cxl/core/pci.c in order to be
exported and shared with CXL Type2 device initialization.

>
> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
> ---
> drivers/cxl/core/pci.c | 63 ++++++++++++++++++++++++++++++++++++++++++
> drivers/cxl/cxlpci.h | 3 ++
> drivers/cxl/pci.c | 60 ----------------------------------------
> 3 files changed, 66 insertions(+), 60 deletions(-)
>
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 57370d9beb32..bf57f081ef8f 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -1079,6 +1079,69 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port)
> }
> EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_reset_detected, CXL);
>
> +/*
> + * Assume that any RCIEP that emits the CXL memory expander class code
> + * is an RCD
> + */
> +bool is_cxl_restricted(struct pci_dev *pdev)
> +{
> + return pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END;
> +}
> +EXPORT_SYMBOL_NS_GPL(is_cxl_restricted, CXL);
> +
> +static int cxl_rcrb_get_comp_regs(struct pci_dev *pdev,
> + struct cxl_register_map *map)
> +{
> + struct cxl_port *port;
> + struct cxl_dport *dport;
> + resource_size_t component_reg_phys;
> +
> + *map = (struct cxl_register_map) {
> + .host = &pdev->dev,
> + .resource = CXL_RESOURCE_NONE,
> + };
> +
> + port = cxl_pci_find_port(pdev, &dport);
> + if (!port)
> + return -EPROBE_DEFER;
> +
> + component_reg_phys = cxl_rcd_component_reg_phys(&pdev->dev, dport);
> +
> + put_device(&port->dev);
> +
> + if (component_reg_phys == CXL_RESOURCE_NONE)
> + return -ENXIO;
> +
> + map->resource = component_reg_phys;
> + map->reg_type = CXL_REGLOC_RBI_COMPONENT;
> + map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE;
> +
> + return 0;
> +}
> +
> +int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
> + struct cxl_register_map *map,
> + u32 *caps)
> +{
> + int rc;
> +
> + rc = cxl_find_regblock(pdev, type, map);
> +
> + /*
> + * If the Register Locator DVSEC does not exist, check if it
> + * is an RCH and try to extract the Component Registers from
> + * an RCRB.
> + */
> + if (rc && type == CXL_REGLOC_RBI_COMPONENT && is_cxl_restricted(pdev))
> + rc = cxl_rcrb_get_comp_regs(pdev, map);
> +
> + if (rc)
> + return rc;
> +
> + return cxl_setup_regs(map, caps);
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_pci_setup_regs, CXL);
> +
> bool cxl_pci_check_caps(struct cxl_dev_state *cxlds, u32 expected_caps,
> u32 *current_caps)
> {
> diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
> index eb59019fe5f3..786b811effba 100644
> --- a/drivers/cxl/cxlpci.h
> +++ b/drivers/cxl/cxlpci.h
> @@ -113,4 +113,7 @@ void read_cdat_data(struct cxl_port *port);
> 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);
> +bool is_cxl_restricted(struct pci_dev *pdev);
> +int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
> + struct cxl_register_map *map, u32 *caps);

Does this need to go to a different header like include/cxl/pci.h or something for type2 consumption?

DJ

> #endif /* __CXL_PCI_H__ */
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index bec660357eec..2b85f87549c2 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -463,66 +463,6 @@ static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds, bool irq_avail)
> return 0;
> }
>
> -/*
> - * Assume that any RCIEP that emits the CXL memory expander class code
> - * is an RCD
> - */
> -static bool is_cxl_restricted(struct pci_dev *pdev)
> -{
> - return pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END;
> -}
> -
> -static int cxl_rcrb_get_comp_regs(struct pci_dev *pdev,
> - struct cxl_register_map *map)
> -{
> - struct cxl_port *port;
> - struct cxl_dport *dport;
> - resource_size_t component_reg_phys;
> -
> - *map = (struct cxl_register_map) {
> - .host = &pdev->dev,
> - .resource = CXL_RESOURCE_NONE,
> - };
> -
> - port = cxl_pci_find_port(pdev, &dport);
> - if (!port)
> - return -EPROBE_DEFER;
> -
> - component_reg_phys = cxl_rcd_component_reg_phys(&pdev->dev, dport);
> -
> - put_device(&port->dev);
> -
> - if (component_reg_phys == CXL_RESOURCE_NONE)
> - return -ENXIO;
> -
> - map->resource = component_reg_phys;
> - map->reg_type = CXL_REGLOC_RBI_COMPONENT;
> - map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE;
> -
> - return 0;
> -}
> -
> -static int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
> - struct cxl_register_map *map, u32 *caps)
> -{
> - int rc;
> -
> - rc = cxl_find_regblock(pdev, type, map);
> -
> - /*
> - * If the Register Locator DVSEC does not exist, check if it
> - * is an RCH and try to extract the Component Registers from
> - * an RCRB.
> - */
> - if (rc && type == CXL_REGLOC_RBI_COMPONENT && is_cxl_restricted(pdev))
> - rc = cxl_rcrb_get_comp_regs(pdev, map);
> -
> - if (rc)
> - return rc;
> -
> - return cxl_setup_regs(map, caps);
> -}
> -
> static int cxl_pci_ras_unmask(struct pci_dev *pdev)
> {
> struct cxl_dev_state *cxlds = pci_get_drvdata(pdev);