apps_reset is LTSSM_EN on i.MX7, i.MX8MQ, i.MX8MM and i.MX8MP platforms. Since the assertion/de-assertion of apps_reset(LTSSM_EN bit) had been wrappered in imx_pcie_ltssm_enable() and imx_pcie_ltssm_disable();
Remove apps_reset toggle in imx_pcie_assert_core_reset() and imx_pcie_deassert_core_reset() functions. Use imx_pcie_ltssm_enable() and imx_pcie_ltssm_disable() to configure apps_reset directly.
Fix fail to enumerate reliably PI7C9X2G608GP (hotplug) at i.MX8MM, which reported By Tim.
Only i.MX7D, i.MX8MQ, i.MX8MM, and i.MX8MP have the apps_reset. With this change, the assertion/deassertion of LTSSM_EN bit are unified into imx_pcie_ltssm_enable() and imx_pcie_ltssm_disable() functions, and aligned with other i.MX platforms.
Reported-by: Tim Harvey tharvey@gateworks.com Closes: https://lore.kernel.org/all/CAJ+vNU3ohR2YKTwC4xoYrc1z-neDoH2TTZcMHDy+poj9=jS... Fixes: ef61c7d8d032 ("PCI: imx6: Deassert apps_reset in imx_pcie_deassert_core_reset()") Cc: stable@vger.kernel.org Signed-off-by: Richard Zhu hongxing.zhu@nxp.com Reviewed-by: Frank Li Frank.Li@nxp.com Tested-by: Tim Harvey tharvey@gateworks.com # imx8mp-venice-gw74xx (i.MX8MP + hotplug capable switch) --- drivers/pci/controller/dwc/pci-imx6.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index 9754cc6e09b9..f5f2ac638f4b 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -860,7 +860,6 @@ static int imx95_pcie_core_reset(struct imx_pcie *imx_pcie, bool assert) static void imx_pcie_assert_core_reset(struct imx_pcie *imx_pcie) { reset_control_assert(imx_pcie->pciephy_reset); - reset_control_assert(imx_pcie->apps_reset);
if (imx_pcie->drvdata->core_reset) imx_pcie->drvdata->core_reset(imx_pcie, true); @@ -872,7 +871,6 @@ static void imx_pcie_assert_core_reset(struct imx_pcie *imx_pcie) static int imx_pcie_deassert_core_reset(struct imx_pcie *imx_pcie) { reset_control_deassert(imx_pcie->pciephy_reset); - reset_control_deassert(imx_pcie->apps_reset);
if (imx_pcie->drvdata->core_reset) imx_pcie->drvdata->core_reset(imx_pcie, false); @@ -1247,6 +1245,9 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp) } }
+ /* Make sure that PCIe LTSSM is cleared */ + imx_pcie_ltssm_disable(dev); + ret = imx_pcie_deassert_core_reset(imx_pcie); if (ret < 0) { dev_err(dev, "pcie deassert core reset failed: %d\n", ret);