On 06/08/07 16:50, Joonwoo Park wrote:
> 2007/8/6, Rafael J. Wysocki <rjw@xxxxxxx>:
>> On Monday, 6 August 2007 15:42, Joonwoo Park wrote:
>> > Hi.
>> > I think that the pci_set_power_state() has bug.
>> > The specification says that some delays is required.
>>
>> And they are in place, AFAICS (from drivers/pci/pci.c):
>>
>> /* Mandatory power management transition delays */
>> /* see PCI PM 1.1 5.6.1 table 18 */
>> if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
>> msleep(pci_pm_d3_delay);
>> else if (state == PCI_D2 || dev->current_state == PCI_D2)
>> udelay(200);
>>
>
> The problem is occurred when state is 'PCI_D0', so those codes can't cover it.
> But pci pm specification 5.4.1 says that when programmed to D0 the
> equivalent of a warm reset, delay for the duration of the D3hot to D0
> Uninitialized state
> transition (10ms) to pci signal drivers remain disabled is required.
>
>> > Simon, please can I know whether it works to you?
>> > It is seems to the things are related.
>> >
>> > Joonwoo Park.
>> >
>> > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>> > index 37c00f6..9f78064 100644
>> > --- a/drivers/pci/pci.c
>> > +++ b/drivers/pci/pci.c
>> > @@ -493,8 +493,14 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
>> > * restore at least the BARs so that the device will be
>> > * accessible to its driver.
>> > */
>> > - if (need_restore)
>> > + if (need_restore) {
>> > + /* The specification also says that "Must ensure that all of
>> > + * its PCI signal drivers remain disabled for the duration of
>> > + * the D3hot to D0 Uninitialized state transition".
>> > + */
>> > + msleep(10);
>>
>> It's too late for the delay.
>>
>
> How about this?
It doesn't fix it.
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 37c00f6..974dd04 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -471,6 +471,8 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state)
> msleep(pci_pm_d3_delay);
> else if (state == PCI_D2 || dev->current_state == PCI_D2)
> udelay(200);
> + else if (state == PCI_D0)
> + msleep(10);
>
> /*
> * Give firmware a chance to be called, such as ACPI _PRx, _PSx
>
>
>> > pci_restore_bars(dev);
>> > + }
>> >
>> > return 0;
>> > }
Your patches have spaces everywhere instead of tabs.
--
Simon Arlott
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