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charset="utf-8" From: Vidya Sagar LTR message should be sent as soon as the Root Port enables LTR in the Endpoint. Set snoop and no-snoop LTR timing and LTR message request before the PCIe link comes up so that the LTR message is sent upstream as soon as LTR is enabled. This addresses the case where the host has not yet programmed Max Snoop/ No-Snoop latencies in config space. Without programming these values, the Endpoint would send 0 latencies to the host. The hardware later compares these requested values with the Max latencies configured by the host and sends the appropriate values upstream once the host sets them. Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Teg= ra194") Reviewed-by: Jon Hunter Tested-by: Jon Hunter Signed-off-by: Vidya Sagar Signed-off-by: Manikanta Maddireddy --- Changes V8: Fix commit message Changes V6 -> V7: Retain FIELD_PREP() usage Changes V1 -> V6: None drivers/pci/controller/dwc/pcie-tegra194.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/contr= oller/dwc/pcie-tegra194.c index 0be701e58238..602ff8131887 100644 --- a/drivers/pci/controller/dwc/pcie-tegra194.c +++ b/drivers/pci/controller/dwc/pcie-tegra194.c @@ -485,15 +485,6 @@ static irqreturn_t tegra_pcie_ep_irq_thread(int irq, v= oid *arg) if (val & PCI_COMMAND_MASTER) { ktime_t timeout; =20 - /* 110us for both snoop and no-snoop */ - val =3D FIELD_PREP(PCI_LTR_VALUE_MASK, 110) | - FIELD_PREP(PCI_LTR_SCALE_MASK, 2) | - LTR_MSG_REQ | - FIELD_PREP(PCI_LTR_NOSNOOP_VALUE, 110) | - FIELD_PREP(PCI_LTR_NOSNOOP_SCALE, 2) | - LTR_NOSNOOP_MSG_REQ; - appl_writel(pcie, val, APPL_LTR_MSG_1); - /* Send LTR upstream */ val =3D appl_readl(pcie, APPL_LTR_MSG_2); val |=3D APPL_LTR_MSG_2_LTR_MSG_REQ_STATE; @@ -1803,6 +1794,15 @@ static void pex_ep_event_pex_rst_deassert(struct teg= ra_pcie_dw *pcie) val |=3D APPL_INTR_EN_L1_0_0_RDLH_LINK_UP_INT_EN; appl_writel(pcie, val, APPL_INTR_EN_L1_0_0); =20 + /* 110us for both snoop and no-snoop */ + val =3D FIELD_PREP(PCI_LTR_VALUE_MASK, 110) | + FIELD_PREP(PCI_LTR_SCALE_MASK, 2) | + LTR_MSG_REQ | + FIELD_PREP(PCI_LTR_NOSNOOP_VALUE, 110) | + FIELD_PREP(PCI_LTR_NOSNOOP_SCALE, 2) | + LTR_NOSNOOP_MSG_REQ; + appl_writel(pcie, val, APPL_LTR_MSG_1); + reset_control_deassert(pcie->core_rst); =20 val =3D dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); --=20 2.34.1