RE: [PATCH v1 1/2] PCI: xilinx-nwl: Update ECAM default value and remove unnecessary code.
From: Havalige, Thippeswamy
Date: Mon Aug 07 2023 - 07:34:42 EST
Ignore this, as I missed adding one patch
> -----Original Message-----
> From: Thippeswamy Havalige <thippeswamy.havalige@xxxxxxx>
> Sent: Monday, August 7, 2023 4:35 PM
> To: linux-kernel@xxxxxxxxxxxxxxx; robh+dt@xxxxxxxxxx;
> bhelgaas@xxxxxxxxxx; krzysztof.kozlowski@xxxxxxxxxx; linux-
> pci@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx
> Cc: lpieralisi@xxxxxxxxxx; Gogada, Bharat Kumar
> <bharat.kumar.gogada@xxxxxxx>; Simek, Michal
> <michal.simek@xxxxxxx>; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; Havalige,
> Thippeswamy <thippeswamy.havalige@xxxxxxx>
> Subject: [PATCH v1 1/2] PCI: xilinx-nwl: Update ECAM default value and
> remove unnecessary code.
>
> Our controller is expecting ECAM size to be programmed by software.
> By programming "NWL_ECAM_VALUE_DEFAULT 12" controller can access up
> to 16MB ECAM region which is used to detect 16 buses, so by updating
> "NWL_ECAM_VALUE_DEFAULT " to 16 so that controller can access up to
> 256MB ECAM region to detect 256 buses.
>
> E_ECAM_CONTROL register from bit 16 to 20 uses this value as input to
> calculate ECAM Size.
>
> The primary,secondary and sub-ordinate bus number registers are updated
> by Linux PCI core, so removing code which is updating primary,secondary and
> sub-ordinate bus numbers of type 1 header 18th offset of ECAM.
>
> Signed-off-by: Thippeswamy Havalige <thippeswamy.havalige@xxxxxxx>
> Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxx>
> ---
> | Reported-by: kernel test robot <lkp@xxxxxxxxx>
> | Closes:
> | https://lore.kernel.org/oe-kbuild-all/202308040330.eMTjX3tF-lkp@intel.
> | com/
> ---
> drivers/pci/controller/pcie-xilinx-nwl.c | 18 +++---------------
> 1 file changed, 3 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c
> b/drivers/pci/controller/pcie-xilinx-nwl.c
> index 176686b..b515019 100644
> --- a/drivers/pci/controller/pcie-xilinx-nwl.c
> +++ b/drivers/pci/controller/pcie-xilinx-nwl.c
> @@ -126,7 +126,7 @@
> #define E_ECAM_CR_ENABLE BIT(0)
> #define E_ECAM_SIZE_LOC GENMASK(20, 16)
> #define E_ECAM_SIZE_SHIFT 16
> -#define NWL_ECAM_VALUE_DEFAULT 12
> +#define NWL_ECAM_VALUE_DEFAULT 16
>
> #define CFG_DMA_REG_BAR GENMASK(2, 0)
> #define CFG_PCIE_CACHE GENMASK(7, 0)
> @@ -165,8 +165,6 @@ struct nwl_pcie {
> u32 ecam_size;
> int irq_intx;
> int irq_misc;
> - u32 ecam_value;
> - u8 last_busno;
> struct nwl_msi msi;
> struct irq_domain *legacy_irq_domain;
> struct clk *clk;
> @@ -625,7 +623,7 @@ static int nwl_pcie_bridge_init(struct nwl_pcie *pcie) {
> struct device *dev = pcie->dev;
> struct platform_device *pdev = to_platform_device(dev);
> - u32 breg_val, ecam_val, first_busno = 0;
> + u32 breg_val, ecam_val;
> int err;
>
> breg_val = nwl_bridge_readl(pcie, E_BREG_CAPABILITIES) &
> BREG_PRESENT; @@ -675,7 +673,7 @@ static int nwl_pcie_bridge_init(struct
> nwl_pcie *pcie)
> E_ECAM_CR_ENABLE, E_ECAM_CONTROL);
>
> nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
> - (pcie->ecam_value << E_ECAM_SIZE_SHIFT),
> + (NWL_ECAM_VALUE_DEFAULT <<
> E_ECAM_SIZE_SHIFT),
> E_ECAM_CONTROL);
>
> nwl_bridge_writel(pcie, lower_32_bits(pcie->phys_ecam_base),
> @@ -683,15 +681,6 @@ static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
> nwl_bridge_writel(pcie, upper_32_bits(pcie->phys_ecam_base),
> E_ECAM_BASE_HI);
>
> - /* Get bus range */
> - ecam_val = nwl_bridge_readl(pcie, E_ECAM_CONTROL);
> - pcie->last_busno = (ecam_val & E_ECAM_SIZE_LOC) >>
> E_ECAM_SIZE_SHIFT;
> - /* Write primary, secondary and subordinate bus numbers */
> - ecam_val = first_busno;
> - ecam_val |= (first_busno + 1) << 8;
> - ecam_val |= (pcie->last_busno << E_ECAM_SIZE_SHIFT);
> - writel(ecam_val, (pcie->ecam_base + PCI_PRIMARY_BUS));
> -
> if (nwl_pcie_link_up(pcie))
> dev_info(dev, "Link is UP\n");
> else
> @@ -792,7 +781,6 @@ static int nwl_pcie_probe(struct platform_device
> *pdev)
> pcie = pci_host_bridge_priv(bridge);
>
> pcie->dev = dev;
> - pcie->ecam_value = NWL_ECAM_VALUE_DEFAULT;
>
> err = nwl_pcie_parse_dt(pcie, pdev);
> if (err) {
> --
> 1.8.3.1