[PATCH] PCI: dwc: clean up computing of msix_tbl

[PATCH] PCI: dwc: clean up computing of msix_tbl

[Jiri Slaby]

Commit 6f5e193bfb55 ("PCI: dwc: Fix dw_pcie_ep_raise_msix_irq() to get
correct MSI-X table address") overcomplicated the computation of the
msix_tbl address. Simplify it as it's simply the addr + offset. Provided
addr is (void *) already.

objdump -d shows no difference after this patch.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 1cdcbd102ce8..c815d36905b6 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -433,7 +433,6 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	struct pci_epf_msix_tbl *msix_tbl;
 	struct pci_epc *epc = ep->epc;
-	struct pci_epf_bar *epf_bar;
 	u32 reg, msg_data, vec_ctrl;
 	unsigned int aligned_offset;
 	u32 tbl_offset;
@@ -446,10 +445,7 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
 	bir = (tbl_offset & PCI_MSIX_TABLE_BIR);
 	tbl_offset &= PCI_MSIX_TABLE_OFFSET;
 
-	epf_bar = ep->epf_bar[bir];
-	msix_tbl = epf_bar->addr;
-	msix_tbl = (struct pci_epf_msix_tbl *)((char *)msix_tbl + tbl_offset);
-
+	msix_tbl = ep->epf_bar[bir]->addr + tbl_offset;
 	msg_addr = msix_tbl[(interrupt_num - 1)].msg_addr;
 	msg_data = msix_tbl[(interrupt_num - 1)].msg_data;
 	vec_ctrl = msix_tbl[(interrupt_num - 1)].vector_ctrl;
-- 
2.26.1

Re: [PATCH] PCI: dwc: clean up computing of msix_tbl

[Lorenzo Pieralisi]

On Mon, Apr 20, 2020 at 08:52:27AM +0200, Jiri Slaby wrote:
> Commit 6f5e193bfb55 ("PCI: dwc: Fix dw_pcie_ep_raise_msix_irq() to get
> correct MSI-X table address") overcomplicated the computation of the
> msix_tbl address. Simplify it as it's simply the addr + offset. Provided
> addr is (void *) already.
> 
> objdump -d shows no difference after this patch.
> 
> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> Cc: Kishon Vijay Abraham I <kishon@ti.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> ---
>  drivers/pci/controller/dwc/pcie-designware-ep.c | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)

Applied to pci/dwc, thanks !

Lorenzo

> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index 1cdcbd102ce8..c815d36905b6 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -433,7 +433,6 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
>  	struct pci_epf_msix_tbl *msix_tbl;
>  	struct pci_epc *epc = ep->epc;
> -	struct pci_epf_bar *epf_bar;
>  	u32 reg, msg_data, vec_ctrl;
>  	unsigned int aligned_offset;
>  	u32 tbl_offset;
> @@ -446,10 +445,7 @@ int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	bir = (tbl_offset & PCI_MSIX_TABLE_BIR);
>  	tbl_offset &= PCI_MSIX_TABLE_OFFSET;
>  
> -	epf_bar = ep->epf_bar[bir];
> -	msix_tbl = epf_bar->addr;
> -	msix_tbl = (struct pci_epf_msix_tbl *)((char *)msix_tbl + tbl_offset);
> -
> +	msix_tbl = ep->epf_bar[bir]->addr + tbl_offset;
>  	msg_addr = msix_tbl[(interrupt_num - 1)].msg_addr;
>  	msg_data = msix_tbl[(interrupt_num - 1)].msg_data;
>  	vec_ctrl = msix_tbl[(interrupt_num - 1)].vector_ctrl;
> -- 
> 2.26.1
>