Re: [PATCH 2/2] PCI: dwc: ep: Use align addr function for dw_pcie_ep_raise_{msi,msix}_irq()

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Oct 17, 2024 at 03:20:55PM +0200, Niklas Cassel wrote:
> Use the dw_pcie_ep_align_addr() function to calculate the alignment in
> dw_pcie_ep_raise_{msi,msix}_irq() instead of open coding the same.
> 
> Signed-off-by: Niklas Cassel <cassel@kernel.org>
> ---
>  .../pci/controller/dwc/pcie-designware-ep.c    | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index 20f67fd85e83..9bafa62bed1d 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -503,7 +503,8 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	u32 msg_addr_lower, msg_addr_upper, reg;
>  	struct dw_pcie_ep_func *ep_func;
>  	struct pci_epc *epc = ep->epc;
> -	unsigned int aligned_offset;
> +	size_t msi_mem_size = epc->mem->window.page_size;
> +	size_t offset;
>  	u16 msg_ctrl, msg_data;
>  	bool has_upper;
>  	u64 msg_addr;
> @@ -531,14 +532,13 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	}
>  	msg_addr = ((u64)msg_addr_upper) << 32 | msg_addr_lower;
>  
> -	aligned_offset = msg_addr & (epc->mem->window.page_size - 1);
> -	msg_addr = ALIGN_DOWN(msg_addr, epc->mem->window.page_size);
> +	msg_addr = dw_pcie_ep_align_addr(epc, msg_addr, &msi_mem_size, &offset);
>  	ret = dw_pcie_ep_map_addr(epc, func_no, 0, ep->msi_mem_phys, msg_addr,
> -				  epc->mem->window.page_size);
> +				  msi_mem_size);

I haven't worked through this; just double checking that this is
correct.  Previously we did ALIGN_DOWN() here, but
dw_pcie_ep_align_addr() uses ALIGN() (not ALIGN_DOWN()).  Similar
below in dw_pcie_ep_raise_msix_irq().

>  	if (ret)
>  		return ret;
>  
> -	writel(msg_data | (interrupt_num - 1), ep->msi_mem + aligned_offset);
> +	writel(msg_data | (interrupt_num - 1), ep->msi_mem + offset);
>  
>  	dw_pcie_ep_unmap_addr(epc, func_no, 0, ep->msi_mem_phys);
>  
> @@ -589,8 +589,9 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	struct pci_epf_msix_tbl *msix_tbl;
>  	struct dw_pcie_ep_func *ep_func;
>  	struct pci_epc *epc = ep->epc;
> +	size_t msi_mem_size = epc->mem->window.page_size;
> +	size_t offset;
>  	u32 reg, msg_data, vec_ctrl;
> -	unsigned int aligned_offset;
>  	u32 tbl_offset;
>  	u64 msg_addr;
>  	int ret;
> @@ -615,14 +616,13 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  		return -EPERM;
>  	}
>  
> -	aligned_offset = msg_addr & (epc->mem->window.page_size - 1);
> -	msg_addr = ALIGN_DOWN(msg_addr, epc->mem->window.page_size);
> +	msg_addr = dw_pcie_ep_align_addr(epc, msg_addr, &msi_mem_size, &offset);
>  	ret = dw_pcie_ep_map_addr(epc, func_no, 0, ep->msi_mem_phys, msg_addr,
>  				  epc->mem->window.page_size);
>  	if (ret)
>  		return ret;
>  
> -	writel(msg_data, ep->msi_mem + aligned_offset);
> +	writel(msg_data, ep->msi_mem + offset);
>  
>  	dw_pcie_ep_unmap_addr(epc, func_no, 0, ep->msi_mem_phys);
>  
> -- 
> 2.47.0
>