Thanks for your review. It is indeed accurate.
> 2024年11月13日 01:48，Bjorn Helgaas <helgaas@xxxxxxxxxx> 写道：
>
> On Tue, Nov 12, 2024 at 07:18:16PM +0800, Mengyuan Lou wrote:
>> Wangxun FF5XXX NICs are same as selection of SFxxx, RP1000 and
>> RP2000 NICS. They may be multi-function devices, but the hardware
>> does not advertise ACS capability.
>>
>> Add this ACS quirk for FF5XXX NICs in pci_quirk_wangxun_nic_acs
>> so the functions can be in independent IOMMU groups.
>>
>> Signed-off-by: Mengyuan Lou <mengyuanlou@xxxxxxxxxxxxx>
>
> I propose the following commit log and comment updates to be clear
> that the hardware actually enforces this isolation. Please
> confirm that they are accurate.
>
> PCI: Add ACS quirk for Wangxun FF5xxx NICs
>
> Wangxun FF5xxx NICs are similar to SFxxx, RP1000 and RP2000 NICs.
> They may be multi-function devices, but they do not advertise an ACS
> capability.
>
> But the hardware does isolate FF5xxx functions as though it had an
> ACS capability and PCI_ACS_RR and PCI_ACS_CR were set in the ACS
> Control register, i.e., all peer-to-peer traffic is directed
> upstream instead of being routed internally.
>
> Add ACS quirk for FF5xxx NICs in pci_quirk_wangxun_nic_acs() so the
> functions can be in independent IOMMU groups.
>
>> ---
>> drivers/pci/quirks.c | 10 ++++++----
>> 1 file changed, 6 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
>> index dccb60c1d9cc..d1973a8fd70c 100644
>> --- a/drivers/pci/quirks.c
>> +++ b/drivers/pci/quirks.c
>> @@ -4996,18 +4996,20 @@ static int pci_quirk_brcm_acs(struct pci_dev *dev, u16 acs_flags)
>> }
>>
>> /*
>> - * Wangxun 10G/1G NICs have no ACS capability, and on multi-function
>> + * Wangxun 40G/25G/10G/1G NICs have no ACS capability, and on multi-function
>> * devices, peer-to-peer transactions are not be used between the functions.
>> * So add an ACS quirk for below devices to isolate functions.
>
> Wangxun 40G/25G/10G/1G NICs have no ACS capability, but on
> multi-function devices, the hardware isolates the functions by
> directing all peer-to-peer traffic upstream as though PCI_ACS_RR and
> PCI_ACS_CR were set.
>
>> * SFxxx 1G NICs(em).
>> * RP1000/RP2000 10G NICs(sp).
>> + * FF5xxx 40G/25G/10G NICs(aml).
>> */
>> static int pci_quirk_wangxun_nic_acs(struct pci_dev *dev, u16 acs_flags)
>> {
>> switch (dev->device) {
>> - case 0x0100 ... 0x010F:
>> - case 0x1001:
>> - case 0x2001:
>> + case 0x0100 ... 0x010F: /* EM */
>> + case 0x1001: case 0x2001: /* SP */
>> + case 0x5010: case 0x5025: case 0x5040: /* AML */
>> + case 0x5110: case 0x5125: case 0x5140: /* AML */
>> return pci_acs_ctrl_enabled(acs_flags,
>> PCI_ACS_SV | PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF);
>> }
>> --
>> 2.43.2
