Re: [PATCH] Bug fix for PME interrupt handler, add Root Status check

[Zhengqiang <zhengqiang10@huawei.com>]

On 2017/9/29 21:12, Rafael J. Wysocki wrote:
> On Fri, Sep 29, 2017 at 8:10 AM, Zhengqiang <zhengqiang10@huawei.com> wrote:
>> Hi,Rafael, thanks for you reply.
>> please see my comment.
>>
>> On 2017/9/29 7:13, Rafael J. Wysocki wrote:
>>> On Thu, Sep 28, 2017 at 5:54 AM, Qiang <zhengqiang10@huawei.com> wrote:
>>>> PCIe PME and hot plug share same interrupt number. In some special case,
>>>> Link down event cause hot plug interrupt, devices is not disconnected,
>>>> But read config will return 0xff.
>>>>
>>>> In that case, PME work function will run and not return Because
>>>> Root Status PME bit always 1 and can not be cleared.
>>>>
>>>> This patch add Root Status check in PME interrupt handler,
>>>> Just do same as pciehp isr Slot status check.
>>>>
>>>> Signed-off-by: Qiang Zheng <zhengqiang10@huawei.com>
>>>> ---
>>>>  drivers/pci/pcie/pme.c | 2 +-
>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/pci/pcie/pme.c b/drivers/pci/pcie/pme.c
>>>> index fafdb16..67144f5 100644
>>>> --- a/drivers/pci/pcie/pme.c
>>>> +++ b/drivers/pci/pcie/pme.c
>>>> @@ -273,7 +273,7 @@ static irqreturn_t pcie_pme_irq(int irq, void *context)
>>>>         spin_lock_irqsave(&data->lock, flags);
>>>>         pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta);
>>>>
>>>> -       if (!(rtsta & PCI_EXP_RTSTA_PME)) {
>>>> +       if (rtsta == (u32)(~0) || !(rtsta & PCI_EXP_RTSTA_PME)) {
>>>>                 spin_unlock_irqrestore(&data->lock, flags);
>>>>                 return IRQ_NONE;
>>>>         }
>>>
>>> OK, but isn't there a symbol for all ones in u32?  And if there isn't,
>>> what about adding it?
>>>
>> Here is Root Status register definitions.
> 
> Well, that's not what I meant.
> 
> You have "rtsta == (u32)(~0)" in the patch above, but you could do
> "rtsta == U32_MAX" instead.
> 
Sure, I will change it next patch .Thanks.

> Thanks,
> Rafael
> 
> .
>