On 2013/1/9 1:44, Bjorn Helgaas wrote:
> [+cc Kenji]
>
> On Tue, Oct 16, 2012 at 1:10 AM, Yijing Wang <wangyijing@xxxxxxxxxx> wrote:
>> ARI device supports up to 256 Functions, pciehp now only scan and configure
>> Functions from 0 to 7, this patch fix this problem for ARI device hotplug.
>>
>> Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx>
>> ---
>> drivers/pci/hotplug/pciehp_pci.c | 40 ++++++++++++++++++++++++++-----------
>> 1 files changed, 28 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
>> index 09cecaf..b37e8a0 100644
>> --- a/drivers/pci/hotplug/pciehp_pci.c
>> +++ b/drivers/pci/hotplug/pciehp_pci.c
>> @@ -39,7 +39,7 @@ int pciehp_configure_device(struct slot *p_slot)
>> struct pci_dev *dev;
>> struct pci_dev *bridge = p_slot->ctrl->pcie->port;
>> struct pci_bus *parent = bridge->subordinate;
>> - int num, fn;
>> + int num, fn = 0;
>> struct controller *ctrl = p_slot->ctrl;
>>
>> dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
>> @@ -56,21 +56,31 @@ int pciehp_configure_device(struct slot *p_slot)
>> ctrl_err(ctrl, "No new device found\n");
>> return -ENODEV;
>> }
>> -
>> - for (fn = 0; fn < 8; fn++) {
>> - dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
>> +
>> + do {
>> + if (pci_ari_enabled(parent))
>> + dev = pci_get_slot(parent, fn);
>> + else
>> + dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
>> +
>> + fn = pci_next_fn(parent, PCI_DEVFN(0, fn));
>
> This doesn't make sense to me. We just called pci_scan_slot(), which
> already used pci_next_fn() to find all the functions. We shouldn't
> have to have the ARI knowledge and pci_next_fn() looping here again
> (and yet again after pci_assign_unassigned_bridge_resources()).
>
> According to the pci_scan_slot() function comment, all the
> newly-discovered devices should be on the bus->devices list. And in
> fact, the similar code in acpiphp (enable_device()) *does* use the
> bus->devices list.
>
Hi Bjorn,
Thanks for your review and comment! You are right, use bus->devices list is a better solution.
I will update my ARI device hotplug support patchset and send out again.
> I think cpci_configure_slot(), pciehp_configure_device(),
> enable_slot() in sgi_hotplug.c, and shpchp_configure_device() should
> be changed to use the bus->devices list. In addition, I think the
> refcount management (pci_get_slot()/pci_dev_put()) should be removed.
Remove pci_get_slot()/pci_dev_put() here looks good to me, Because refcount increment when pci_scan_slot,
here remove the refcount management is safe.
I will change this and test in my machine, and send out this patch if test result is ok.
Thanks very much!
Yijing.
>
>> if (!dev)
>> continue;
>> if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
>> (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS))
>> pci_hp_add_bridge(dev);
>> pci_dev_put(dev);
>> - }
>> + } while (fn);
>>
>> pci_assign_unassigned_bridge_resources(bridge);
>>
>> - for (fn = 0; fn < 8; fn++) {
>> - dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
>> + do {
>> + if (pci_ari_enabled(parent))
>> + dev = pci_get_slot(parent, fn);
>> + else
>> + dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
>> +
>> + fn = pci_next_fn(parent, PCI_DEVFN(0, fn));
>> if (!dev)
>> continue;
>> if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
>> @@ -79,7 +89,7 @@ int pciehp_configure_device(struct slot *p_slot)
>> }
>> pci_configure_slot(dev);
>> pci_dev_put(dev);
>> - }
>> + } while (fn);
>>
>> pci_bus_add_devices(parent);
>>
>> @@ -89,21 +99,27 @@ int pciehp_configure_device(struct slot *p_slot)
>> int pciehp_unconfigure_device(struct slot *p_slot)
>> {
>> int ret, rc = 0;
>> - int j;
>> + int fn = 0;
>> u8 bctl = 0;
>> u8 presence = 0;
>> struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
>> u16 command;
>> struct controller *ctrl = p_slot->ctrl;
>> + struct pci_dev *temp;
>>
>> ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
>> __func__, pci_domain_nr(parent), parent->number);
>> ret = pciehp_get_adapter_status(p_slot, &presence);
>> if (ret)
>> presence = 0;
>> +
>> + do {
>> + if (pci_ari_enabled(parent))
>> + temp = pci_get_slot(parent, fn);
>> + else
>> + temp = pci_get_slot(parent, PCI_DEVFN(0, fn));
>>
>> - for (j = 0; j < 8; j++) {
>> - struct pci_dev *temp = pci_get_slot(parent, PCI_DEVFN(0, j));
>> + fn = pci_next_fn(parent, PCI_DEVFN(0, fn));
>> if (!temp)
>> continue;
>> if (temp->hdr_type == PCI_HEADER_TYPE_BRIDGE && presence) {
>> @@ -129,7 +145,7 @@ int pciehp_unconfigure_device(struct slot *p_slot)
>> pci_write_config_word(temp, PCI_COMMAND, command);
>> }
>> pci_dev_put(temp);
>> - }
>> + } while (fn);
>>
>> return rc;
>> }
>> --
>> 1.7.1
>>
>>
>
> .
>
--
Thanks!
Yijing
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