lkml.org 
[lkml]   [2019]   [Jul]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30
    On Fri, Jul 19, 2019 at 12:10:50AM -0400, Sasha Levin wrote:
    > From: Vidya Sagar <vidyas@nvidia.com>
    >
    > [ Upstream commit 7be142caabc4780b13a522c485abc806de5c4114 ]
    >
    > The PCI Tegra controller conversion to a device tree configurable
    > driver in commit d1523b52bff3 ("PCI: tegra: Move PCIe driver
    > to drivers/pci/host") implied that code for the driver can be
    > compiled in for a kernel supporting multiple platforms.
    >
    > Unfortunately, a blind move of the code did not check that some of the
    > quirks that were applied in arch/arm (eg enabling Relaxed Ordering on
    > all PCI devices - since the quirk hook erroneously matches PCI_ANY_ID
    > for both Vendor-ID and Device-ID) are now applied in all kernels that
    > compile the PCI Tegra controlled driver, DT and ACPI alike.
    >
    > This is completely wrong, in that enablement of Relaxed Ordering is only
    > required by default in Tegra20 platforms as described in the Tegra20
    > Technical Reference Manual (available at
    > https://developer.nvidia.com/embedded/downloads#?search=tegra%202 in
    > Section 34.1, where it is mentioned that Relaxed Ordering bit needs to
    > be enabled in its root ports to avoid deadlock in hardware) and in the
    > Tegra30 platforms for the same reasons (unfortunately not documented
    > in the TRM).
    >
    > There is no other strict requirement on PCI devices Relaxed Ordering
    > enablement on any other Tegra platforms or PCI host bridge driver.
    >
    > Fix this quite upsetting situation by limiting the vendor and device IDs
    > to which the Relaxed Ordering quirk applies to the root ports in
    > question, reported above.
    >
    > Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
    > [lorenzo.pieralisi@arm.com: completely rewrote the commit log/fixes tag]
    > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
    > Acked-by: Thierry Reding <treding@nvidia.com>
    > Signed-off-by: Sasha Levin <sashal@kernel.org>

    Hi Sasha,

    as Jon requested, please drop this patch from the autosel patch
    queue, thank you very much.

    Lorenzo

    > ---
    > drivers/pci/host/pci-tegra.c | 7 +++++--
    > 1 file changed, 5 insertions(+), 2 deletions(-)
    >
    > diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
    > index 1987fec1f126..d2ad76ef3e83 100644
    > --- a/drivers/pci/host/pci-tegra.c
    > +++ b/drivers/pci/host/pci-tegra.c
    > @@ -607,12 +607,15 @@ 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)
    > {
    > --
    > 2.20.1
    >

    \
     
     \ /
      Last update: 2019-07-19 15:54    [W:3.180 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site