[PATCH v5 0/3] PCI: dwc: Skip waiting for link up if vendor drivers can detect Link up event

[Krishna chaitanya chundru <quic_krichai@quicinc.com>]

If the vendor drivers can detect the Link up event using mechanisms
such as Link up IRQ, then waiting for Link up during probe is not
needed. if the drivers can be notified when the link comes up,
vendor driver can enumerate downstream devices instead of waiting
here, which optimizes the boot time.

So skip waiting for link to be up if the driver supports 'use_linkup_irq'.

Currently, only Qcom RC driver supports the 'use_linkup_irq' as it can
detect the Link Up event using its own 'global IRQ' interrupt. So set
'use_linkup_irq' flag for QCOM drivers.

And as part of the PCIe link up event, the ICC and OPP values are updated.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
Changes in v5:
- update the commit text as suggested by (mani).
Changes in v4:
- change the linkup_irq name to use_linkup_irq a suggested by (bjorn
  andresson)
- update commit text as suggested by bjorn andresson.
- Link to v3: https://lore.kernel.org/r/linux-arm-msm/20241101-remove_wait-v3-0-7accf27f7202@quicinc.com/T/
Changes in v3:
- seperate dwc changes and qcom changes as suggested (mani)
- update commit & comments as suggested (mani & bjorn)
- Link to v2: https://lore.kernel.org/linux-pci/20240920-remove_wait-v2-0-7c0fcb3b581d@quicinc.com/T/
Changes in v2:
- Updated the bypass_link_up_wait name to linkup_irq  & added comment as
  suggested (mani).
- seperated the icc and opp update patch (mani).
- Link to v1: https://lore.kernel.org/r/20240917-remove_wait-v1-1-456d2551bc50@quicinc.com

---
Krishna chaitanya chundru (3):
      PCI: dwc: Skip waiting for link up if vendor drivers can detect Link up event
      PCI: qcom: Set use_linkup_irq if global IRQ handler is present
      PCI: qcom: Update ICC and OPP values during link up event

 drivers/pci/controller/dwc/pcie-designware-host.c | 10 ++++++++--
 drivers/pci/controller/dwc/pcie-designware.h      |  1 +
 drivers/pci/controller/dwc/pcie-qcom.c            |  7 ++++++-
 3 files changed, 15 insertions(+), 3 deletions(-)
---
base-commit: cfba9f07a1d6aeca38f47f1f472cfb0ba133d341
change-id: 20241122-remove_wait2-d581b40380ea

Best regards,
-- 
Krishna chaitanya chundru <quic_krichai@quicinc.com>