PCI: tegra194: Fix polling delay for L2 state

As per PCIe r7.0, sec 5.3.3.2.1, after sending PME_Turn_Off message, Root
Port should wait for 1-10 msec for PME_TO_Ack message. Currently, driver is
polling for 10 msec with 1 usec delay which is aggressive.  Use existing
macro PCIE_PME_TO_L2_TIMEOUT_US to poll for 10 msec with 1 msec delay.
Since this function is used in non-atomic context only, use non-atomic poll
function.

Fixes: 56e15a238d92 ("PCI: tegra: Add Tegra194 PCIe support")
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://patch.msgid.link/20260324190755.1094879-2-mmaddireddy@nvidia.com

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 06571d806ab31fa7d6e2866db1c895764220c8a1..13949f6f7d5be866f4f51e16e8caf61148663df1 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -198,8 +198,6 @@
 #define CAP_SPCIE_CAP_OFF_USP_TX_PRESET0_MASK  GENMASK(11, 8)
 #define CAP_SPCIE_CAP_OFF_USP_TX_PRESET0_SHIFT 8
 
-#define PME_ACK_TIMEOUT 10000
-
 #define LTSSM_TIMEOUT 50000    /* 50ms */
 
 #define GEN3_GEN4_EQ_PRESET_INIT       5
@@ -1553,9 +1551,10 @@ static int tegra_pcie_try_link_l2(struct tegra_pcie_dw *pcie)
        val |= APPL_PM_XMT_TURNOFF_STATE;
        appl_writel(pcie, val, APPL_RADM_STATUS);
 
-       return readl_poll_timeout_atomic(pcie->appl_base + APPL_DEBUG, val,
-                                val & APPL_DEBUG_PM_LINKST_IN_L2_LAT,
-                                1, PME_ACK_TIMEOUT);
+       return readl_poll_timeout(pcie->appl_base + APPL_DEBUG, val,
+                                 val & APPL_DEBUG_PM_LINKST_IN_L2_LAT,
+                                 PCIE_PME_TO_L2_TIMEOUT_US/10,
+                                 PCIE_PME_TO_L2_TIMEOUT_US);
 }
 
 static void tegra_pcie_dw_pme_turnoff(struct tegra_pcie_dw *pcie)