Re: [PATCH v7 3/6] PCI: endpoint: Add pci_epf_align_addr() helper for address alignment

[Niklas Cassel <cassel@kernel.org>]

On Thu, Nov 14, 2024 at 05:52:39PM -0500, Frank Li wrote:
> Introduce the helper function pci_epf_align_addr() to adjust addresses
> according to PCI BAR alignment requirements, converting addresses into base
> and offset values.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> change from v6 to v7
> - new patch
> ---
>  drivers/pci/endpoint/pci-epf-core.c | 39 +++++++++++++++++++++++++++++++++++++
>  include/linux/pci-epf.h             | 13 +++++++++++++
>  2 files changed, 52 insertions(+)
> 
> diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
> index 8fa2797d4169a..a3f172cc786e9 100644
> --- a/drivers/pci/endpoint/pci-epf-core.c
> +++ b/drivers/pci/endpoint/pci-epf-core.c
> @@ -464,6 +464,45 @@ struct pci_epf *pci_epf_create(const char *name)
>  }
>  EXPORT_SYMBOL_GPL(pci_epf_create);
>  
> +/**
> + * pci_epf_align_addr() - Get base address and offset that match bar's
> + *			  alignment requirement
> + * @epf: the EPF device
> + * @addr: the address of the memory
> + * @bar: the BAR number corresponding to map addr
> + * @base: return base address, which match BAR's alignment requirement, nothing
> + *	  return if NULL
> + * @off: return offset, nothing return if NULL
> + *
> + * Helper function to convert input 'addr' to base and offset, which match
> + * BAR's alignment requirement.

Should we perhaps also mention that this function is not needed in the
"normal case" ? (i.e. pci_epf_alloc_space() + pci_epc_set_bar())


Kind regards,
Niklas