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charset="utf-8" After the link reaches a detect-related LTSSM state, disable LTSSM so it do= es not keep toggling between polling and detect. Do this by polling for the detect state first, then clearing APPL_CTRL_LTSSM_EN in both tegra_pcie_dw_pme_turnoff() and pex_ep_event_pex_rst_assert(). Fixes: 56e15a238d92 ("PCI: tegra: Add Tegra194 PCIe support") Reviewed-by: Jon Hunter Tested-by: Jon Hunter Signed-off-by: Vidya Sagar Signed-off-by: Manikanta Maddireddy --- Changes V8: Split into two patches drivers/pci/controller/dwc/pcie-tegra194.c | 29 ++++++++++++---------- 1 file changed, 16 insertions(+), 13 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/contr= oller/dwc/pcie-tegra194.c index 5b243c006562..baee73438638 100644 --- a/drivers/pci/controller/dwc/pcie-tegra194.c +++ b/drivers/pci/controller/dwc/pcie-tegra194.c @@ -1594,14 +1594,6 @@ static void tegra_pcie_dw_pme_turnoff(struct tegra_p= cie_dw *pcie) data &=3D ~APPL_PINMUX_PEX_RST; appl_writel(pcie, data, APPL_PINMUX); =20 - /* - * Some cards do not go to detect state even after de-asserting - * PERST#. So, de-assert LTSSM to bring link to detect state. - */ - data =3D readl(pcie->appl_base + APPL_CTRL); - data &=3D ~APPL_CTRL_LTSSM_EN; - writel(data, pcie->appl_base + APPL_CTRL); - err =3D readl_poll_timeout(pcie->appl_base + APPL_DEBUG, data, ((data & APPL_DEBUG_LTSSM_STATE_MASK) =3D=3D LTSSM_STATE_DETECT_QUIET) = || ((data & APPL_DEBUG_LTSSM_STATE_MASK) =3D=3D LTSSM_STATE_DETECT_ACT) || @@ -1610,6 +1602,14 @@ static void tegra_pcie_dw_pme_turnoff(struct tegra_p= cie_dw *pcie) LTSSM_DELAY_US, LTSSM_TIMEOUT_US); if (err) dev_info(pcie->dev, "LTSSM state: 0x%x detect timeout: %d\n", data, err= ); + + /* + * Deassert LTSSM state to stop the state toggling between + * polling and detect. + */ + data =3D readl(pcie->appl_base + APPL_CTRL); + data &=3D ~APPL_CTRL_LTSSM_EN; + writel(data, pcie->appl_base + APPL_CTRL); } /* * DBI registers may not be accessible after this as PLL-E would be @@ -1683,11 +1683,6 @@ static void pex_ep_event_pex_rst_assert(struct tegra= _pcie_dw *pcie) if (pcie->ep_state =3D=3D EP_STATE_DISABLED) return; =20 - /* Disable LTSSM */ - val =3D appl_readl(pcie, APPL_CTRL); - val &=3D ~APPL_CTRL_LTSSM_EN; - appl_writel(pcie, val, APPL_CTRL); - ret =3D readl_poll_timeout(pcie->appl_base + APPL_DEBUG, val, ((val & APPL_DEBUG_LTSSM_STATE_MASK) =3D=3D LTSSM_STATE_DETECT_QUIET) || ((val & APPL_DEBUG_LTSSM_STATE_MASK) =3D=3D LTSSM_STATE_DETECT_ACT) || @@ -1698,6 +1693,14 @@ static void pex_ep_event_pex_rst_assert(struct tegra= _pcie_dw *pcie) if (ret) dev_info(pcie->dev, "LTSSM state: 0x%x detect timeout: %d\n", val, ret); =20 + /* + * Deassert LTSSM state to stop the state toggling between + * polling and detect. + */ + val =3D appl_readl(pcie, APPL_CTRL); + val &=3D ~APPL_CTRL_LTSSM_EN; + appl_writel(pcie, val, APPL_CTRL); + reset_control_assert(pcie->core_rst); =20 tegra_pcie_disable_phy(pcie); --=20 2.34.1