Re: [PATCH v8 5/8] PCI: cadence: Simplify code to get register base address for configuring BAR

From: Bjorn Helgaas
Date: Tue Aug 17 2021 - 11:24:21 EST


On Wed, Aug 11, 2021 at 12:16:53PM +0530, Kishon Vijay Abraham I wrote:
> No functional change. Simplify code to get register base address for
> configuring PCI BAR.
>
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> .../pci/controller/cadence/pcie-cadence-ep.c | 18 ++++--------------
> drivers/pci/controller/cadence/pcie-cadence.h | 2 ++
> 2 files changed, 6 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
> index 912a15be8bfd..f337f0842400 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
> @@ -97,13 +97,8 @@ static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, u8 vfn,
> cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar),
> addr1);
>
> - if (bar < BAR_4) {
> - reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
> - b = bar;
> - } else {
> - reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
> - b = bar - BAR_4;
> - }
> + reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG(bar, fn);
> + b = (bar < BAR_4) ? bar : bar - BAR_4;
>
> cfg = cdns_pcie_readl(pcie, reg);
> cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
> @@ -126,13 +121,8 @@ static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn, u8 vfn,
> enum pci_barno bar = epf_bar->barno;
> u32 reg, cfg, b, ctrl;
>
> - if (bar < BAR_4) {
> - reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
> - b = bar;
> - } else {
> - reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
> - b = bar - BAR_4;
> - }
> + reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG(bar, fn);
> + b = (bar < BAR_4) ? bar : bar - BAR_4;
>
> ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
> cfg = cdns_pcie_readl(pcie, reg);
> diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
> index 30db2d68c17a..d5b1fcf2c39d 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence.h
> +++ b/drivers/pci/controller/cadence/pcie-cadence.h
> @@ -46,6 +46,8 @@
> #define CDNS_PCIE_LM_EP_ID_BUS_SHIFT 8
>
> /* Endpoint Function f BAR b Configuration Registers */
> +#define CDNS_PCIE_LM_EP_FUNC_BAR_CFG(bar, fn) \
> + (((bar) < 4) ? CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn) : CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn))

Why do we use "BAR_4" above and "4" here? Shouldn't they look the
same?

> #define CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn) \
> (CDNS_PCIE_LM_BASE + 0x0240 + (fn) * 0x0008)
> #define CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn) \
> --
> 2.17.1
>