+ Bjorn for PCI.
On 2023/11/22 21:14, Ilpo Järvinen wrote:
Hi, Ilpo,
Thank you for your reply. Please see my comments inline.
> On Tue, 21 Nov 2023, Shuai Xue wrote:
>
>> The clear and set pattern is commonly used for accessing PCI config,
>> move the helper pci_clear_and_set_dword() from aspm.c into PCI header.
>> In addition, rename to pci_clear_and_set_config_dword() to retain the
>> "config" information and match the other accessors.
>>
>> No functional change intended.
>>
>> Signed-off-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx>
>> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>> Tested-by: Ilkka Koskinen <ilkka@xxxxxxxxxxxxxxxxxxxxxx>
>> ---
>> drivers/pci/access.c | 12 ++++++++
>> drivers/pci/pcie/aspm.c | 65 +++++++++++++++++++----------------------
>> include/linux/pci.h | 2 ++
>> 3 files changed, 44 insertions(+), 35 deletions(-)
>>
>> diff --git a/drivers/pci/access.c b/drivers/pci/access.c
>> index 6554a2e89d36..6449056b57dd 100644
>> --- a/drivers/pci/access.c
>> +++ b/drivers/pci/access.c
>> @@ -598,3 +598,15 @@ int pci_write_config_dword(const struct pci_dev *dev, int where,
>> return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val);
>> }
>> EXPORT_SYMBOL(pci_write_config_dword);
>> +
>> +void pci_clear_and_set_config_dword(const struct pci_dev *dev, int pos,
>> + u32 clear, u32 set)
>
> Just noting that annoyingly the ordering within the name is inconsistent
> between:
> pci_clear_and_set_config_dword()
> and
> pcie_capability_clear_and_set_dword()
>
> And if changed, it would be again annoyingly inconsistent with
> pci_read/write_config_*(), oh well... And renaming pci_read/write_config_*
> into the hierarchical pci_config_read/write_*() form for would touch only
> ~6k lines... ;-D
I think it is a good question, but I don't have a clear answer. I don't
know much about the name history. As you mentioned, the above two
accessors are the foundation operation, may it comes to @Bjorn decision.
The pci_clear_and_set_config_dword() is a variant of bellow pci accessors:
pci_read_config_dword()
pci_write_config_dword()
At last, they are consistend :)
>
>> + pci_clear_and_set_config_dword(child,
>> + child->l1ss + PCI_L1SS_CTL1, 0,
>> + cl1_2_enables);
>
> Adding clear and set only variants into the header like there are for
> pcie_capability_*() would remove the need to add those 0 parameters.
> IMO, it improves code readability considerably.
>
Agreed.
Best Regards,
Shuai
