Re: [PATCHv3 17/27] PCI: mobiveil: fix the checking of valid device

[Subrahmanya Lingappa]

ZQ,

On Tue, Jan 29, 2019 at 1:40 PM Z.q. Hou <zhiqiang.hou@xxxxxxx> wrote:
>
> From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
>
> Avoid to issue CFG transactions to link partner when the PCIe
> link is not up. And allow CFG transactions to all functions of
> Endpoint implemented multiple functions.
>
> Fixes: 9af6bcb11e12 ("PCI: mobiveil: Add Mobiveil PCIe Host
> Bridge IP driver")
> Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
> Reviewed-by: Minghuan Lian <Minghuan.Lian@xxxxxxx>
> ---
> V3:
>  - No change
>
>  drivers/pci/controller/mobiveil/pcie-mobiveil-host.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c b/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c
> index dc5324d94466..1ae82e790562 100644
> --- a/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c
> +++ b/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c
> @@ -29,6 +29,10 @@ static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
>  {
>         struct mobiveil_pcie *pcie = bus->sysdata;
>
> +       /* If there is no link, then there is no device */
> +       if (bus->number > pcie->rp.root_bus_nr && !mobiveil_pcie_link_up(pcie))
> +               return false;
> +
>         /* Only one device down on each root port */
>         if ((bus->number == pcie->rp.root_bus_nr) && (devfn > 0))
>                 return false;
> @@ -37,7 +41,7 @@ static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
>          * Do not read more than one device on the bus directly
>          * attached to RC
>          */
> -       if ((bus->primary == pcie->rp.root_bus_nr) && (devfn > 0))
> +       if ((bus->primary == pcie->rp.root_bus_nr) && (PCI_SLOT(devfn) > 0))
here change "primary" to "number", as it's a bug in the original driver too.

>                 return false;
>
>         return true;
> --
> 2.17.1
>