>>> On 29.11.17 at 16:37, <[email protected]> wrote:
> On 11/9/2017 2:49 AM, Jan Beulich wrote:
>>>>> On 09.11.17 at 00:06, <[email protected]> wrote:
>>> +static int pcistub_reset_dev(struct pci_dev *dev)
>>> +{
>>> + struct xen_pcibk_dev_data *dev_data;
>>> + bool slot = false, bus = false;
>>> + struct pcistub_args arg = {};
>>> +
>>> + if (!dev)
>>> + return -EINVAL;
>>> +
>>> + dev_dbg(&dev->dev, "[%s]\n", __func__);
>>> +
>>> + if (!pci_probe_reset_slot(dev->slot))
>>> + slot = true;
>>> + else if ((!pci_probe_reset_bus(dev->bus)) &&
>>> + (!pci_is_root_bus(dev->bus)))
>>> + bus = true;
>>> +
>>> + if (!bus && !slot)
>>> + return -EOPNOTSUPP;
>>> +
>>> + /*
>>> + * Make sure all devices on this bus are owned by the
>>> + * PCI backend so that we can safely reset the whole bus.
>>> + */
>> Is that really the case when you mean to do a slot reset? It was for
>> a reason that I had asked about a missing "else" in v1 review,
>> rather than questioning the conditional around the logic.
>
> In the case of bus or slot reset, our goal is to reset connected PCIe
> fabric/card/endpoint.
> The connected card/endpoint can be multi-function device. So, same
> walk-through and checking
> is needed irrespective of type of reset being used.
I don't follow: The scope of other devices/functions possibly
affected by a reset depends on the type of reset, doesn't it?
Jan
From 1585423168831191758@xxx Wed Nov 29 17:42:36 +0000 2017
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>> In the case of bus or slot reset, our goal is to reset connected PCIe
>> fabric/card/endpoint.
>> The connected card/endpoint can be multi-function device. So, same
>> walk-through and checking
>> is needed irrespective of type of reset being used.
> I don't follow: The scope of other devices/functions possibly
> affected by a reset depends on the type of reset, doesn't it?
For PCIe platforms, both slot and bus reset endup resetting all connected
device/functions on thesecondary bus (behind the root-port or
downstream-port).
Cheers
GOVINDA
From 1585415384923729106@xxx Wed Nov 29 15:38:53 +0000 2017
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