From 7763cc24e2103a54eb43bbe46fca59ddab77c2f2 Mon Sep 17 00:00:00 2001 From: Manikanta Maddireddy Date: Tue, 18 Jun 2019 23:31:48 +0530 Subject: [PATCH] PCI: tegra: Enable opportunistic UpdateFC and ACK Enable opportunistic UpdateFC and ACK to allow data link layer send pending ACKs and UpdateFC packets when link is idle instead of waiting for timers to expire. This improves the PCIe performance due to better utilization of PCIe bandwidth. Signed-off-by: Manikanta Maddireddy Signed-off-by: Lorenzo Pieralisi Acked-by: Thierry Reding --- drivers/pci/controller/pci-tegra.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index 2d0a23b2c7bb..cd69c43c9a0c 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -204,7 +204,9 @@ #define RP_ECTL_6_R2_RX_EQ_CTRL_H_1C_MASK 0xffffffff #define RP_VEND_XP 0x00000f00 -#define RP_VEND_XP_DL_UP (1 << 30) +#define RP_VEND_XP_DL_UP (1 << 30) +#define RP_VEND_XP_OPPORTUNISTIC_ACK (1 << 27) +#define RP_VEND_XP_OPPORTUNISTIC_UPDATEFC (1 << 28) #define RP_VEND_CTL1 0x00000f48 #define RP_VEND_CTL1_ERPT (1 << 13) @@ -529,6 +531,12 @@ static void tegra_pcie_enable_rp_features(struct tegra_pcie_port *port) value = readl(port->base + RP_VEND_CTL1); value |= RP_VEND_CTL1_ERPT; writel(value, port->base + RP_VEND_CTL1); + + /* Optimal settings to enhance bandwidth */ + value = readl(port->base + RP_VEND_XP); + value |= RP_VEND_XP_OPPORTUNISTIC_ACK; + value |= RP_VEND_XP_OPPORTUNISTIC_UPDATEFC; + writel(value, port->base + RP_VEND_XP); } static void tegra_pcie_program_ectl_settings(struct tegra_pcie_port *port) -- 2.30.2