mbox series

[v1,0/2] Fix ecam size value to discover 256 buses during

Message ID 20230807110436.77287-1-thippeswamy.havalige@amd.com
Headers
Series Fix ecam size value to discover 256 buses during |

Message

Havalige, Thippeswamy Aug. 7, 2023, 11:04 a.m. UTC 
  Current driver is supports up to 16 buses. The following code fixes 
to support up to 256 buses.

update "NWL_ECAM_VALUE_DEFAULT " to 16  can access up to 256MB ECAM
region to detect 256 buses.

Remove redundant code which updates primary,secondary and sub-ordinate
register offset 0x18 in type1 header.

Update ecam size to 256MB in device tree binding example.

Thippeswamy Havalige (2):
  PCI: xilinx-nwl: Update ECAM default value and remove unnecessary    
    code.
  dt-bindings: PCI: xilinx-nwl: Modify ECAM size in example.

 .../devicetree/bindings/pci/xlnx,nwl-pcie.yaml         |  2 +-
 drivers/pci/controller/pcie-xilinx-nwl.c               | 18 +++---------------
 2 files changed, 4 insertions(+), 16 deletions(-)

Comments

Havalige, Thippeswamy Aug. 7, 2023, 11:14 a.m. UTC | #1 
Ignore this, as I missed adding one patch

> -----Original Message-----
> From: Thippeswamy Havalige <thippeswamy.havalige@amd.com>
> Sent: Monday, August 7, 2023 4:35 PM
> To: linux-kernel@vger.kernel.org; robh+dt@kernel.org;
> bhelgaas@google.com; krzysztof.kozlowski@linaro.org; linux-
> pci@vger.kernel.org; devicetree@vger.kernel.org
> Cc: lpieralisi@kernel.org; Gogada, Bharat Kumar
> <bharat.kumar.gogada@amd.com>; Simek, Michal
> <michal.simek@amd.com>; linux-arm-kernel@lists.infradead.org; Havalige,
> Thippeswamy <thippeswamy.havalige@amd.com>
> 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@amd.com>
> Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@amd.com>
> ---
> | Reported-by: kernel test robot <lkp@intel.com>
> | 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