Merge branch 'pci/controller/dwc-tegra194'

- Program the DesignWare PORT_AFR L1 entrance latency based on the
  'aspm-l1-entry-delay-ns' DT property (Manikanta Maddireddy)

* pci/controller/dwc-tegra194:
  PCI: tegra194: Use aspm-l1-entry-delay-ns DT property for L1 entrance latency
This commit is contained in:
Bjorn Helgaas 2026-06-23 17:32:15 -05:00
commit 81c4ead83e

View File

@ -272,6 +272,7 @@ struct tegra_pcie_dw {
u32 aspm_cmrt;
u32 aspm_pwr_on_t;
u32 aspm_l0s_enter_lat;
u32 aspm_l1_enter_lat;
struct regulator *pex_ctl_supply;
struct regulator *slot_ctl_3v3;
@ -715,6 +716,8 @@ static void init_host_aspm(struct tegra_pcie_dw *pcie)
val = dw_pcie_readl_dbi(pci, PCIE_PORT_AFR);
val &= ~PORT_AFR_L0S_ENTRANCE_LAT_MASK;
val |= (pcie->aspm_l0s_enter_lat << PORT_AFR_L0S_ENTRANCE_LAT_SHIFT);
val &= ~PORT_AFR_L1_ENTRANCE_LAT_MASK;
val |= (pcie->aspm_l1_enter_lat << PORT_AFR_L1_ENTRANCE_LAT_SHIFT);
val |= PORT_AFR_ENTER_ASPM;
dw_pcie_writel_dbi(pci, PCIE_PORT_AFR, val);
}
@ -1115,6 +1118,7 @@ static int tegra_pcie_dw_parse_dt(struct tegra_pcie_dw *pcie)
{
struct platform_device *pdev = to_platform_device(pcie->dev);
struct device_node *np = pcie->dev->of_node;
u32 val;
int ret;
pcie->dbi_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
@ -1141,6 +1145,15 @@ static int tegra_pcie_dw_parse_dt(struct tegra_pcie_dw *pcie)
dev_info(pcie->dev,
"Failed to read ASPM L0s Entrance latency: %d\n", ret);
/* Default to max latency of 7. */
pcie->aspm_l1_enter_lat = 7;
ret = of_property_read_u32(np, "aspm-l1-entry-delay-ns", &val);
if (!ret) {
u32 us = DIV_ROUND_UP(val, 1000);
pcie->aspm_l1_enter_lat = min_t(u32, order_base_2(us), 7);
}
ret = of_property_read_u32(np, "num-lanes", &pcie->num_lanes);
if (ret < 0) {
dev_err(pcie->dev, "Failed to read num-lanes: %d\n", ret);