Re: [PATCH v3 8/9] PCI: rockchip-ep: Set a 64-bit BAR if requested

[Bjorn Helgaas <helgaas@xxxxxxxxxx>]

On Wed, Mar 13, 2024 at 11:58:00AM +0100, Niklas Cassel wrote:
> ...

> --- a/drivers/pci/controller/pcie-rockchip-ep.c
> +++ b/drivers/pci/controller/pcie-rockchip-ep.c
> @@ -153,7 +153,7 @@ static int rockchip_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, u8 vfn,
>  		ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_IO_32BITS;
>  	} else {
>  		bool is_prefetch = !!(flags & PCI_BASE_ADDRESS_MEM_PREFETCH);
> -		bool is_64bits = sz > SZ_2G;
> +		bool is_64bits = !!(flags & PCI_BASE_ADDRESS_MEM_TYPE_64);
>  
>  		if (is_64bits && (bar & 1))
>  			return -EINVAL;

Completely unrelated to *these* patches, but the BAR_CFG_CTRL
definitions in both cadence and rockchip lead to some awkward case
analysis:

  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM_32BITS              0x4
  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH_MEM_32BITS     0x5
  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM_64BITS              0x6
  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH_MEM_64BITS     0x7

  if (is_64bits && is_prefetch)
          ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH_MEM_64BITS;
  else if (is_prefetch)
          ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH_MEM_32BITS;
  else if (is_64bits)
          ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM_64BITS;
  else
          ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM_32BITS;

that *could* be just something like this:

  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM           0x4
  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_64BITS        0x2
  #define ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH      0x1

  ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM;
  if (is_64bits)
    ctrl |= ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_64BITS;
  if (is_prefetch)
    ctrl |= ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH;