(2010/08/04 17:41), Hidetoshi Seto wrote:
> (2010/08/04 14:46), Kenji Kaneshige wrote:
>> (2010/08/04 6:02), Rafael J. Wysocki wrote:
>>> On Tuesday, August 03, 2010, Rafael J. Wysocki wrote:
>>>> On Tuesday, August 03, 2010, Hidetoshi Seto wrote:
>>>>> (2010/08/03 13:52), Kenji Kaneshige wrote:
>>>>>> (2010/08/03 6:59), Rafael J. Wysocki wrote:
>>>>>>> @@ -434,19 +432,6 @@ acpi_status acpi_pci_osc_control_set(acp
>>>>>>> if ((root->osc_control_set& control_req) == control_req)
>>>>>>> goto out;
>>>>>>>
>>>>>>> - /* Need to query controls first before requesting them */
>>>>>>> - if (!root->osc_queried) {
>>>>>>> - status = acpi_pci_query_osc(root, root->osc_support_set, NULL);
>>>>>>> - if (ACPI_FAILURE(status))
>>>>>>> - goto out;
>>>>>>> - }
>>>>>>> - if ((root->osc_control_qry& control_req) != control_req) {
>>>>>>> - printk(KERN_DEBUG
>>>>>>> - "Firmware did not grant requested _OSC control\n");
>>>>>>> - status = AE_SUPPORT;
>>>>>>> - goto out;
>>>>>>> - }
>>>>>>
>>>>>> I think acpi_pci_osc_control_set() still need to query before commit
>>>>>> to ensure all the requested controls are granted to OS.
>>>>>>
>>>>>> So the code needs to be
>>>>>>
>>>>>> status = acpi_pci_query_osc(root, root->osc_support_set,&control_req);
>>>>>> if (ACPI_FAILURE(status))
>>>>>> goto out;
>>>>>
>>
>> Sorry, that should have been
>>
>> query = control_req;
>> status = acpi_pci_query_osc(root, root->osc_support_set,&query);
>> if (ACPI_FAILURE(status))
>> goto out;
>> if ((query& control_req) != control_req) {
>> printk_(KERN_DEBUG
>> "Firmware did not grant requested _OSC control\n");
>> status = AE_SUPPORT;
>> goto out;
>> }
>>
>> I know current pcie_port_acpi_setup() queries the requesting controls
>> before acpi_pci_osc_control_set() and only one control is requested
>> in the other code. However, I think acpi_pci_osc_control_set() still
>> need to query the requested controls to ensure all the requested
>> controls, in case someone calls this function without querying the
>> requesting controls. In other words, I think it must be ensured that
>> any controls are never granted to OS when acpi_pci_osc_control_set()
>> returns error.
>
> I think the following patch is what you mean.
Thank you! Yes, it is what I meant.
And the patch looks good to me.
Thanks,
Kenji Kaneshige
>
> And... (Continue to next post)
>
> Thanks,
> H.Seto
>
> =====
>
> From: Rafael J. Wysocki<rjw@xxxxxxx>
> Subject: ACPI / PCI: Do not preserve _OSC control bits returned by a query (v3)
>
> All of the remaining callers of acpi_pci_osc_control_set() either
> use acpi_pci_root_osc_query() right before it, like
> pcie_port_acpi_setup(), or ask for control of one feature only,
> like acpi_get_hp_hw_control_from_firmware(). Thus there is no
> reason to preserve the _OSC control bits returned by an _OSC query
> and the osc_control_qry and osc_queried fields of struct
> acpi_pci_root are not necessary any more. Remove them and modify the
> code that uses them accordingly.
>
> [v3: HS: keep query in acpi_pci_osc_control_set]
>
> Signed-off-by: Rafael J. Wysocki<rjw@xxxxxxx>
> Signed-off-by: Hidetoshi Seto<seto.hidetoshi@xxxxxxxxxxxxxx>
> ---
> drivers/acpi/pci_root.c | 13 +++++--------
> include/acpi/acpi_bus.h | 3 ---
> 2 files changed, 5 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> index d3110d6..ec03c19 100644
> --- a/drivers/acpi/pci_root.c
> +++ b/drivers/acpi/pci_root.c
> @@ -248,10 +248,8 @@ static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
> status = acpi_pci_run_osc(root->device->handle, capbuf,&result);
> if (ACPI_SUCCESS(status)) {
> root->osc_support_set = support;
> - root->osc_control_qry = result;
> if (control)
> *control = result;
> - root->osc_queried = 1;
> }
> return status;
> }
> @@ -438,12 +436,11 @@ acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
> goto out;
>
> /* Need to query controls first before requesting them */
> - if (!root->osc_queried) {
> - status = acpi_pci_query_osc(root, root->osc_support_set, NULL);
> - if (ACPI_FAILURE(status))
> - goto out;
> - }
> - if ((root->osc_control_qry& control_req) != control_req) {
> + result = control_req;
> + status = acpi_pci_query_osc(root, root->osc_support_set,&result);
> + if (ACPI_FAILURE(status))
> + goto out;
> + if ((result& control_req) != control_req) {
> printk(KERN_DEBUG
> "Firmware did not grant requested _OSC control\n");
> status = AE_SUPPORT;
> diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
> index baacd98..4de84ce 100644
> --- a/include/acpi/acpi_bus.h
> +++ b/include/acpi/acpi_bus.h
> @@ -377,9 +377,6 @@ struct acpi_pci_root {
>
> u32 osc_support_set; /* _OSC state of support bits */
> u32 osc_control_set; /* _OSC state of control bits */
> - u32 osc_control_qry; /* the latest _OSC query result */
> -
> - u32 osc_queried:1; /* has _OSC control been queried? */
> };
>
> /* helper */
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