Re: [PATCH v12 05/23] cxl: add function for type2 cxl regs setup

[Simon Horman <horms@kernel.org>]

On Mon, Mar 31, 2025 at 03:45:37PM +0100, alejandro.lucero-palau@amd.com wrote:
> From: Alejandro Lucero <alucerop@amd.com>
> 
> Create a new function for a type2 device initialising
> cxl_dev_state struct regarding cxl regs setup and mapping.
> 
> Export the capabilities found for checking them against the
> expected ones by the driver.
> 
> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
> Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com>
> ---
>  drivers/cxl/core/pci.c | 52 ++++++++++++++++++++++++++++++++++++++++++
>  include/cxl/cxl.h      |  5 ++++
>  2 files changed, 57 insertions(+)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 05399292209a..e48320e16a4f 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -1095,6 +1095,58 @@ int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
>  }
>  EXPORT_SYMBOL_NS_GPL(cxl_pci_setup_regs, "CXL");
>  
> +static int cxl_pci_setup_memdev_regs(struct pci_dev *pdev,
> +				     struct cxl_dev_state *cxlds,
> +				     unsigned long *caps)
> +{
> +	struct cxl_register_map map;
> +	int rc;
> +
> +	rc = cxl_pci_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map, caps);
> +	/*
> +	 * This call can return -ENODEV if regs not found. This is not an error
> +	 * for Type2 since these regs are not mandatory. If they do exist then
> +	 * mapping them should not fail. If they should exist, it is with driver
> +	 * calling cxl_pci_check_caps where the problem should be found.
> +	 */
> +	if (rc == -ENODEV)
> +		return 0;
> +
> +	if (rc)
> +		return rc;
> +
> +	return cxl_map_device_regs(&map, &cxlds->regs.device_regs);
> +}
> +
> +int cxl_pci_accel_setup_regs(struct pci_dev *pdev, struct cxl_dev_state *cxlds,
> +			      unsigned long *caps)

nit: the indentation of the line above is not quite aligned
     to the inside of the opening parentheses on the previous line.
     There is one space too many.

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