[PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[Sasha Levin]

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>
---
 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

Re: [PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[Jon Hunter]

Hi Lorenzo,

We have not requested that this is added to stable yet, however, has
been picked up. Do we wish to let it soak in mainline for a release
first? If so maybe we can ask Sasha to drop this for now.

Cheers
Jon

On 19/07/2019 05:10, 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>
> ---
>  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)
>  {
> 

-- 
nvpublic

Re: [PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[Sasha Levin]

On Fri, Jul 19, 2019 at 09:33:11AM +0100, Jon Hunter wrote:
>Hi Lorenzo,
>
>We have not requested that this is added to stable yet, however, has
>been picked up. Do we wish to let it soak in mainline for a release
>first? If so maybe we can ask Sasha to drop this for now.

Note that there are about two weeks between this mail and the point
where it actually appears in a stable tree.

AUTOSEL patches follow a much slower pace than ones marked for stable
exactly for the reason you've mentioned.

--
Thanks,
Sasha

Re: [PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[Lorenzo Pieralisi]

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
> 

Re: [PATCH AUTOSEL 4.14 41/60] PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30

[Sasha Levin]

On Fri, Jul 19, 2019 at 02:53:09PM +0100, Lorenzo Pieralisi wrote:
>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.

Now dropped from the queue, thanks!

--
Thanks,
Sasha