drivers/pci/controller/dwc/pcie-tegra194.c | 8 ++++++++ 1 file changed, 8 insertions(+)
For Tegra234, the HW PHY team conducted experiments and determined the
optimal ASPM L1 entrance latency values: 8 us for Root Port mode and
16 us for Endpoint mode. Update the default ASPM L1 entrance latency
configuration accordingly.
Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
---
V5:
* None
V4:
* None
V3:
* None
V2:
* None
drivers/pci/controller/dwc/pcie-tegra194.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 82e9ef172de1..1b4fc6a9bed1 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -244,6 +244,8 @@ struct tegra_pcie_dw_of_data {
u32 cdm_chk_int_en_bit;
u32 gen4_preset_vec;
u8 n_fts[2];
+ /* L1 Latency entrance values(Rest/Prod) */
+ u32 aspm_l1_enter_lat;
};
struct tegra_pcie_dw {
@@ -714,6 +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->of_data->aspm_l1_enter_lat << PORT_AFR_L1_ENTRANCE_LAT_SHIFT);
val |= PORT_AFR_ENTER_ASPM;
dw_pcie_writel_dbi(pci, PCIE_PORT_AFR, val);
}
@@ -2471,6 +2475,7 @@ static const struct tegra_pcie_dw_of_data tegra194_pcie_dw_rc_of_data = {
/* Gen4 - 5, 6, 8 and 9 presets enabled */
.gen4_preset_vec = 0x360,
.n_fts = { 52, 52 },
+ .aspm_l1_enter_lat = 3,
};
static const struct tegra_pcie_dw_of_data tegra194_pcie_dw_ep_of_data = {
@@ -2480,6 +2485,7 @@ static const struct tegra_pcie_dw_of_data tegra194_pcie_dw_ep_of_data = {
/* Gen4 - 5, 6, 8 and 9 presets enabled */
.gen4_preset_vec = 0x360,
.n_fts = { 52, 52 },
+ .aspm_l1_enter_lat = 3,
};
static const struct tegra_pcie_dw_of_data tegra234_pcie_dw_rc_of_data = {
@@ -2492,6 +2498,7 @@ static const struct tegra_pcie_dw_of_data tegra234_pcie_dw_rc_of_data = {
/* Gen4 - 6, 8 and 9 presets enabled */
.gen4_preset_vec = 0x340,
.n_fts = { 52, 80 },
+ .aspm_l1_enter_lat = 4,
};
static const struct tegra_pcie_dw_of_data tegra234_pcie_dw_ep_of_data = {
@@ -2504,6 +2511,7 @@ static const struct tegra_pcie_dw_of_data tegra234_pcie_dw_ep_of_data = {
/* Gen4 - 6, 8 and 9 presets enabled */
.gen4_preset_vec = 0x340,
.n_fts = { 52, 80 },
+ .aspm_l1_enter_lat = 5,
};
static const struct of_device_id tegra_pcie_dw_of_match[] = {
--
2.34.1
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