[PATCH V3 16/21] PCI: tegra194: Set LTR message request before PCIe link up

Vidya Sagar vidyas at nvidia.com
Thu Oct 13 11:38:49 PDT 2022


LTR message should be sent as soon as the root port enables LTR in the
endpoint. Set snoop & no snoop LTR timing and LTR message request before
PCIe links up. This ensures that LTR message is sent upstream as soon as
LTR is enabled.

Signed-off-by: Vidya Sagar <vidyas at nvidia.com>
---
V3:
* This is a new patch in this series

 drivers/pci/controller/dwc/pcie-tegra194.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index d592cf68b02c..23ca97401339 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -493,11 +493,6 @@ static irqreturn_t tegra_pcie_ep_irq_thread(int irq, void *arg)
 	if (val & PCI_COMMAND_MASTER) {
 		ktime_t timeout;
 
-		/* 110us for both snoop and no-snoop */
-		val = 110 | (2 << PCI_LTR_SCALE_SHIFT) | LTR_MSG_REQ;
-		val |= (val << LTR_MST_NO_SNOOP_SHIFT);
-		appl_writel(pcie, val, APPL_LTR_MSG_1);
-
 		/* Send LTR upstream */
 		val = appl_readl(pcie, APPL_LTR_MSG_2);
 		val |= APPL_LTR_MSG_2_LTR_MSG_REQ_STATE;
@@ -1951,6 +1946,11 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
 	val |= APPL_INTR_EN_L1_8_EDMA_INT_EN;
 	appl_writel(pcie, val, APPL_INTR_EN_L1_8_0);
 
+	/* 110us for both snoop and no-snoop */
+	val = 110 | (2 << PCI_LTR_SCALE_SHIFT) | LTR_MSG_REQ;
+	val |= (val << LTR_MST_NO_SNOOP_SHIFT);
+	appl_writel(pcie, val, APPL_LTR_MSG_1);
+
 	reset_control_deassert(pcie->core_rst);
 
 	val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
-- 
2.17.1




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