| Message ID | 20190220094841.11129-1-thomas.petazzoni@bootlin.com |
|---|---|
| Headers | show |
| Series | PCI: fix pci-mvebu after conversion to common bridge emul code | expand |
On Wed, Feb 20, 2019 at 10:48:39AM +0100, Thomas Petazzoni wrote: > Hello, > > This set of two patches aim at fixing some regression reported by two > users (Luis and Leigh), that were introduced by the conversion of the > pci-mvebu driver to the common PCI bridge emulation code shared > between pci-aardvark and pci-mvebu. > > Due to this conversion, some registers of the PCI configuration that > used to be read-only are now read-write, making the Linux PCI core > believe that some features are implemented by the PCI bridge. Namely > in the case of pci-mvebu, the prefetchable memory base/limit registers > were read-only, while they are now read-write. Due to this, the Linux > PCI core now believes it can configure a prefetchable memory area, but > this is not supported by pci-mvebu, which does not have the logic to > create the appropriate MBUs windows. > > This set of two commits allow PCI controller code to tell the PCI > bridge emulation logic about their capabilities. Because we envision > that other capabilities than prefetchable memory support might need to > be communicated from the PCI controller code to the PCI bridge > emulation code in the future, we introduce a "flags" argument, even if > for now only one flag is supported. > > Lorenzo, let me know what you think about this approach. I am open to > suggestions if the proposed approach is not satisfying. > > Both patches have been confirmed by Luis and Leigh to fix the > regression, but I'll let them give a formal Tested-by. > > Best regards, > > Thomas Petazzoni > > Thomas Petazzoni (2): > PCI: pci-bridge-emul: Create per-bridge copy of register behavior > PCI: pci-bridge-emul: Extend pci_bridge_emul_init() with flags > > drivers/pci/controller/pci-aardvark.c | 2 +- > drivers/pci/controller/pci-mvebu.c | 2 +- > drivers/pci/pci-bridge-emul.c | 86 ++++++++++++++++++--------- > drivers/pci/pci-bridge-emul.h | 13 +++- > 4 files changed, 73 insertions(+), 30 deletions(-) Lorenzo, I assume you'll take both of these, so for both patches, Acked-by: Bjorn Helgaas <bhelgaas@google.com> Maybe we should add a stable tag (v4.20+)?
On 2019-02-20 09:48, Thomas Petazzoni wrote: > Hello, > > This set of two patches aim at fixing some regression reported by two > users (Luis and Leigh), that were introduced by the conversion of the > pci-mvebu driver to the common PCI bridge emulation code shared > between pci-aardvark and pci-mvebu. > > Due to this conversion, some registers of the PCI configuration that > used to be read-only are now read-write, making the Linux PCI core > believe that some features are implemented by the PCI bridge. Namely > in the case of pci-mvebu, the prefetchable memory base/limit registers > were read-only, while they are now read-write. Due to this, the Linux > PCI core now believes it can configure a prefetchable memory area, but > this is not supported by pci-mvebu, which does not have the logic to > create the appropriate MBUs windows. > > This set of two commits allow PCI controller code to tell the PCI > bridge emulation logic about their capabilities. Because we envision > that other capabilities than prefetchable memory support might need to > be communicated from the PCI controller code to the PCI bridge > emulation code in the future, we introduce a "flags" argument, even if > for now only one flag is supported. > > Lorenzo, let me know what you think about this approach. I am open to > suggestions if the proposed approach is not satisfying. > > Both patches have been confirmed by Luis and Leigh to fix the > regression, but I'll let them give a formal Tested-by. > > Best regards, > > Thomas Petazzoni > > Thomas Petazzoni (2): > PCI: pci-bridge-emul: Create per-bridge copy of register behavior > PCI: pci-bridge-emul: Extend pci_bridge_emul_init() with flags > > drivers/pci/controller/pci-aardvark.c | 2 +- > drivers/pci/controller/pci-mvebu.c | 2 +- > drivers/pci/pci-bridge-emul.c | 86 ++++++++++++++++++--------- > drivers/pci/pci-bridge-emul.h | 13 +++- > 4 files changed, 73 insertions(+), 30 deletions(-) Tested on WRT1900ACS router against 4.20.7 and 5.0.0-rc. Tested-by: Leigh Brown <leigh@solinno.co.uk> Regards, Leigh.
On 2019-02-21 23:23, Bjorn Helgaas wrote: > On Wed, Feb 20, 2019 at 10:48:39AM +0100, Thomas Petazzoni wrote: >> Hello, >> >> This set of two patches aim at fixing some regression reported by two >> users (Luis and Leigh), that were introduced by the conversion of the >> pci-mvebu driver to the common PCI bridge emulation code shared >> between pci-aardvark and pci-mvebu. >> >> Due to this conversion, some registers of the PCI configuration that >> used to be read-only are now read-write, making the Linux PCI core >> believe that some features are implemented by the PCI bridge. Namely >> in the case of pci-mvebu, the prefetchable memory base/limit registers >> were read-only, while they are now read-write. Due to this, the Linux >> PCI core now believes it can configure a prefetchable memory area, but >> this is not supported by pci-mvebu, which does not have the logic to >> create the appropriate MBUs windows. >> >> This set of two commits allow PCI controller code to tell the PCI >> bridge emulation logic about their capabilities. Because we envision >> that other capabilities than prefetchable memory support might need to >> be communicated from the PCI controller code to the PCI bridge >> emulation code in the future, we introduce a "flags" argument, even if >> for now only one flag is supported. >> >> Lorenzo, let me know what you think about this approach. I am open to >> suggestions if the proposed approach is not satisfying. >> >> Both patches have been confirmed by Luis and Leigh to fix the >> regression, but I'll let them give a formal Tested-by. >> >> Best regards, >> >> Thomas Petazzoni >> >> Thomas Petazzoni (2): >> PCI: pci-bridge-emul: Create per-bridge copy of register behavior >> PCI: pci-bridge-emul: Extend pci_bridge_emul_init() with flags >> >> drivers/pci/controller/pci-aardvark.c | 2 +- >> drivers/pci/controller/pci-mvebu.c | 2 +- >> drivers/pci/pci-bridge-emul.c | 86 >> ++++++++++++++++++--------- >> drivers/pci/pci-bridge-emul.h | 13 +++- >> 4 files changed, 73 insertions(+), 30 deletions(-) > > Lorenzo, I assume you'll take both of these, so for both patches, > > Acked-by: Bjorn Helgaas <bhelgaas@google.com> > > Maybe we should add a stable tag (v4.20+)? That would be great, as it would get that kernel version working again. Regards, Leigh.
Hello Bjorn, On Thu, 21 Feb 2019 17:23:17 -0600 Bjorn Helgaas <helgaas@kernel.org> wrote: > Lorenzo, I assume you'll take both of these, so for both patches, > > Acked-by: Bjorn Helgaas <bhelgaas@google.com> Thanks! > Maybe we should add a stable tag (v4.20+)? Both patches have a Fixes: tag, so they should be automatically be backported to the applicable stable kernels. From Documentation/process/submitting-patches.rst. A Fixes: tag indicates that the patch fixes an issue in a previous commit. It is used to make it easy to determine where a bug originated, which can help review a bug fix. This tag also assists the stable kernel team in determining which stable kernel versions should receive your fix. This is the preferred method for indicating a bug fixed by the patch. See :ref:`describe_changes` for more details. Isn't that sufficient ? Thanks, Thomas
On Fri, Feb 22, 2019 at 09:35:54AM +0100, Thomas Petazzoni wrote: > Hello Bjorn, > > On Thu, 21 Feb 2019 17:23:17 -0600 > Bjorn Helgaas <helgaas@kernel.org> wrote: > > > Lorenzo, I assume you'll take both of these, so for both patches, > > > > Acked-by: Bjorn Helgaas <bhelgaas@google.com> > > Thanks! > > > Maybe we should add a stable tag (v4.20+)? > > Both patches have a Fixes: tag, so they should be automatically be > backported to the applicable stable kernels. From > Documentation/process/submitting-patches.rst. > > A Fixes: tag indicates that the patch fixes an issue in a previous > commit. It is used to make it easy to determine where a bug > originated, which can help review a bug fix. This tag also assists > the stable kernel team in determining which stable kernel versions > should receive your fix. This is the preferred method for indicating > a bug fixed by the patch. See :ref:`describe_changes` for more > details. > > Isn't that sufficient ? Adding a CC: stable won't hurt so that it is certain it will get stable kernels attention, that's what I will do. Thanks, Lorenzo
On Wed, Feb 20, 2019 at 10:48:39AM +0100, Thomas Petazzoni wrote: > Hello, > > This set of two patches aim at fixing some regression reported by two > users (Luis and Leigh), that were introduced by the conversion of the > pci-mvebu driver to the common PCI bridge emulation code shared > between pci-aardvark and pci-mvebu. > > Due to this conversion, some registers of the PCI configuration that > used to be read-only are now read-write, making the Linux PCI core > believe that some features are implemented by the PCI bridge. Namely > in the case of pci-mvebu, the prefetchable memory base/limit registers > were read-only, while they are now read-write. Due to this, the Linux > PCI core now believes it can configure a prefetchable memory area, but > this is not supported by pci-mvebu, which does not have the logic to > create the appropriate MBUs windows. > > This set of two commits allow PCI controller code to tell the PCI > bridge emulation logic about their capabilities. Because we envision > that other capabilities than prefetchable memory support might need to > be communicated from the PCI controller code to the PCI bridge > emulation code in the future, we introduce a "flags" argument, even if > for now only one flag is supported. > > Lorenzo, let me know what you think about this approach. I am open to > suggestions if the proposed approach is not satisfying. > > Both patches have been confirmed by Luis and Leigh to fix the > regression, but I'll let them give a formal Tested-by. > > Best regards, > > Thomas Petazzoni > > Thomas Petazzoni (2): > PCI: pci-bridge-emul: Create per-bridge copy of register behavior > PCI: pci-bridge-emul: Extend pci_bridge_emul_init() with flags > > drivers/pci/controller/pci-aardvark.c | 2 +- > drivers/pci/controller/pci-mvebu.c | 2 +- > drivers/pci/pci-bridge-emul.c | 86 ++++++++++++++++++--------- > drivers/pci/pci-bridge-emul.h | 13 +++- > 4 files changed, 73 insertions(+), 30 deletions(-) I have applied the series to pci/misc for v5.1, thanks. Lorenzo
Hello Lorenzo, On Fri, 22 Feb 2019 11:05:12 +0000 Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > > Isn't that sufficient ? > > Adding a CC: stable won't hurt so that it is certain it will get > stable kernels attention, that's what I will do. Ah, yes, indeed. Sorry for forgetting about these, and thanks for applying with those Cc: stable added! Thomas