Re: [PATCH] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>]

On Tue, Jun 18, 2019 at 01:08:10PM +0530, Vidya Sagar wrote:
> Currently Relaxed Ordering bit in the configuration space is enabled for
> all devices whereas it should be enabled only for root ports for Tegra20
> and Tegra30 chips to avoid deadlock in hardware.

This is a fix so I think you had better add a Fixes: tag and if the
erratum is a public document it would be good to add it to the log
to explain what the problem is.

Thanks,
Lorenzo

> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> ---
>  drivers/pci/controller/pci-tegra.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c
> index 464ba2538d52..bc7be369c1b3 100644
> --- a/drivers/pci/controller/pci-tegra.c
> +++ b/drivers/pci/controller/pci-tegra.c
> @@ -545,12 +545,15 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x0bf1, tegra_pcie_fixup_class);
>  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x0e1c, tegra_pcie_fixup_class);
>  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_NVIDIA, 0x0e1d, tegra_pcie_fixup_class);
>  
> -/* Tegra PCIE requires relaxed ordering */
> +/* Tegra20 and Tegra30 PCIE requires relaxed ordering */
>  static void tegra_pcie_relax_enable(struct pci_dev *dev)
>  {
>  	pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_RELAX_EN);
>  }
> -DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, tegra_pcie_relax_enable);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x0bf0, tegra_pcie_relax_enable);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x0bf1, tegra_pcie_relax_enable);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x0e1c, tegra_pcie_relax_enable);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x0e1d, tegra_pcie_relax_enable);
>  
>  static int tegra_pcie_request_resources(struct tegra_pcie *pcie)
>  {
> -- 
> 2.17.1
>