[ Upstream commit 68bc10bf99 ]
This bug was introduced in the interaction for two commits on either
branch of the merge commit 562df5c852 ("Merge branch
'pci/host-designware' into next").
Commit 4d107d3b5a ("PCI: imx6: Move link up check into
imx6_pcie_wait_for_link()"), changed imx6_pcie_wait_for_link() to poll
the link status register directly, checking for link up and not
training, and made imx6_pcie_link_up() only check the link up bit (once,
not a polling loop).
While commit 886bc5ceb5 ("PCI: designware: Add generic
dw_pcie_wait_for_link()"), replaced the loop in
imx6_pcie_wait_for_link() with a call to a new dwc core function, which
polled imx6_pcie_link_up(), which still checked both link up and not
training in a loop.
When these two commits were merged, the version of
imx6_pcie_wait_for_link() from 886bc5ceb5 was kept, which eliminated
the link training check placed there by 4d107d3b5a. However, the
version of imx6_pcie_link_up() from 4d107d3b5a was kept, which
eliminated the link training check that had been there and was moved to
imx6_pcie_wait_for_link().
The result was the link training check got lost for the imx6 driver.
Eliminate imx6_pcie_link_up() so that the default handler,
dw_pcie_link_up(), is used instead. The default handler has the correct
code, which checks for link up and also that it still is not training,
fixing the regression.
Fixes: 562df5c852 ("Merge branch 'pci/host-designware' into next")
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
[lorenzo.pieralisi@arm.com: rewrote the commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Joao Pinto <Joao.Pinto@synopsys.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2a031cab71