PCI: qcom: Set up rev 2.1.0 PARF_PHY before enabling clocks

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We currently enable clocks BEFORE we write to PARF_PHY_CTRL reg to enable
clocks and resets. This causes the driver to never set to a ready state
with the error 'Phy link never came up'.

This is caused by the PHY clock getting enabled before setting the required
bits in the PARF regs.

A workaround for this was set but with this new discovery we can drop
the workaround and use a proper solution to the problem by just enabling
the clock only AFTER the PARF_PHY_CTRL bit is set.

This correctly sets up the PCIe link and makes it usable even when a
bootloader leaves the PCIe link in an undefined state.

Fixes: 82a823833f ("PCI: qcom: Add Qualcomm PCIe controller driver")
Link: https://lore.kernel.org/r/20220708222743.27019-1-ansuelsmth@gmail.com
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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Christian Marangi 2022-07-09 00:27:43 +02:00 • committed by Bjorn Helgaas

parent 553d12b20c

commit 38f897ae3d

1 changed files with 4 additions and 6 deletions

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drivers/pci/controller/dwc/pcie-qcom.c

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