[PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Heiner Kallweit]

On 06.01.2021 20:22, Bjorn Helgaas wrote:
> On Wed, Jan 06, 2021 at 06:50:22PM +0100, Heiner Kallweit wrote:
>> If we know that a device has broken parity checking, then disable it.
>> This avoids quirks like in r8169 where on the first parity error
>> interrupt parity checking will be disabled if broken_parity_status
>> is set. Make pci_quirk_broken_parity() public so that it can be used
>> by platform code, e.g. for Thecus N2100.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1 at gmail.com>
>> Reviewed-by: Leon Romanovsky <leonro at nvidia.com>
> 
> Acked-by: Bjorn Helgaas <bhelgaas at google.com>
> 
> This series should all go together.  Let me know if you want me to do
> anything more (would require acks for arm and r8169, of course).
> 
Right. For r8169 I'm the maintainer myself and agreed with Jakub that
the r8169 patch will go through the PCI tree.

Regarding the arm/iop32x part:
MAINTAINERS file lists Lennert as maintainer, let me add him.
Strange thing is that the MAINTAINERS entry for arm/iop32x has no
F entry, therefore the get_maintainers scripts will never list him
as addressee. The script lists Russell as "odd fixer".
@Lennert: Please provide a patch to add the missing F entry.

ARM/INTEL IOP32X ARM ARCHITECTURE
M:	Lennert Buytenhek <kernel at wantstofly.org>
L:	linux-arm-kernel at lists.infradead.org (moderated for non-subscribers)
S:	Maintained


>> ---
>>  drivers/pci/quirks.c | 17 +++++++++++------
>>  include/linux/pci.h  |  2 ++
>>  2 files changed, 13 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
>> index 653660e3b..ab54e26b8 100644
>> --- a/drivers/pci/quirks.c
>> +++ b/drivers/pci/quirks.c
>> @@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
>>  DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
>>  				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
>>  
>> +void pci_quirk_broken_parity(struct pci_dev *dev)
>> +{
>> +	u16 cmd;
>> +
>> +	dev->broken_parity_status = 1;	/* This device gives false positives */
>> +	pci_read_config_word(dev, PCI_COMMAND, &cmd);
>> +	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
>> +}
>> +
>>  /*
>>   * The Mellanox Tavor device gives false positive parity errors.  Mark this
>>   * device with a broken_parity_status to allow PCI scanning code to "skip"
>>   * this now blacklisted device.
>>   */
>> -static void quirk_mellanox_tavor(struct pci_dev *dev)
>> -{
>> -	dev->broken_parity_status = 1;	/* This device gives false positives */
>> -}
>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
>>  
>>  /*
>>   * Deal with broken BIOSes that neglect to enable passive release,
>> diff --git a/include/linux/pci.h b/include/linux/pci.h
>> index b32126d26..161dcc474 100644
>> --- a/include/linux/pci.h
>> +++ b/include/linux/pci.h
>> @@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
>>  	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
>>  };
>>  
>> +void pci_quirk_broken_parity(struct pci_dev *dev);
>> +
>>  #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
>>  #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
>>  				    class_shift, hook)			\
>> -- 
>> 2.30.0
>>
>>
>>