On 8/17/2023 12:34 PM, Bart Van Assche wrote:
On 8/17/23 12:00, Bao D. Nguyen wrote:
In legacy SDB mode with auto-hibernation enabled, the default setting
for the
driver_preserves_write_order = false.
>
Using the default setting, it may be missing this check that is part
of the
ufshcd_auto_hibern8_update()->ufshcd_update_preserves_write_order().
If auto-hibernation is enabled by the host driver,
driver_preserves_write_order
is set by the following code in ufshcd_slave_configure():
q->limits.driver_preserves_write_order =
!ufshcd_is_auto_hibern8_supported(hba) ||
FIELD_GET(UFSHCI_AHIBERN8_TIMER_MASK, hba->ahit) == 0;
Does this answer your question?
Hi Bart,
My concern is that in the ufshcd_update_preserves_write_order() you have
this logic:
if (!preserves_write_order) {
shost_for_each_device(sdev, hba->host) {
struct request_queue *q = sdev->request_queue;
/*...*/
if (blk_queue_is_zoned(q) && !q->elevator)
return -EPERM;
}
}
The above logic is only invoked when ufshcd_auto_hibern8_update() is
called. During initialization, ufshcd_auto_hibern8_update() is not
called. Therefore, you may have SDB mode with auto hibernate enabled ->
preserves_write_order = false, and (blk_queue_is_zoned(q) &&
!q->elevator) is true. Is that a problem? If you called
ufshcd_auto_hibern8_update() during ufs probe, you would have returned
-EPERM and not enable auto-hibernation in that case.
Thanks,
Bao
Thanks,
Bart.
