4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 68bc10bf992180f269816ff3d22eb30383138577 ]
This bug was introduced in the interaction for two commits on either branch of the merge commit 562df5c8521e ("Merge branch 'pci/host-designware' into next").
Commit 4d107d3b5a68 ("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 886bc5ceb5cc ("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 886bc5ceb5cc was kept, which eliminated the link training check placed there by 4d107d3b5a68. However, the version of imx6_pcie_link_up() from 4d107d3b5a68 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: 562df5c8521e ("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 --- drivers/pci/controller/dwc/pci-imx6.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index 4a9a673b4777..975050a69494 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -80,8 +80,6 @@ struct imx6_pcie { #define PCIE_PL_PFLR_FORCE_LINK (1 << 15) #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28) #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c) -#define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING (1 << 29) -#define PCIE_PHY_DEBUG_R1_XMLH_LINK_UP (1 << 4)
#define PCIE_PHY_CTRL (PL_OFFSET + 0x114) #define PCIE_PHY_CTRL_DATA_LOC 0 @@ -641,12 +639,6 @@ static int imx6_pcie_host_init(struct pcie_port *pp) return 0; }
-static int imx6_pcie_link_up(struct dw_pcie *pci) -{ - return dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1) & - PCIE_PHY_DEBUG_R1_XMLH_LINK_UP; -} - static const struct dw_pcie_host_ops imx6_pcie_host_ops = { .host_init = imx6_pcie_host_init, }; @@ -679,7 +671,7 @@ static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, }
static const struct dw_pcie_ops dw_pcie_ops = { - .link_up = imx6_pcie_link_up, + /* No special ops needed, but pcie-designware still expects this struct */ };
static int imx6_pcie_probe(struct platform_device *pdev)