From ca1989084054e64da25662e1f974f77312083eb3 Mon Sep 17 00:00:00 2001 From: Shawn Lin Date: Tue, 4 Oct 2016 12:20:22 -0500 Subject: [PATCH] PCI: rockchip: Fix wrong transmitted FTS count If the expected number of FTS aren't received by RC when exiting from L0s, the LTSSM will fall into recover state, which means it will need to send TS for retraining which makes the latency of exiting from L0s a little longer than expected. This issue is caused by an incorrect reset value of FTS count on PLC1 register (offset 0x4). The expected value for Gen1/2 should be more than 240 and we may leave a little margin here. Fix this before starting Gen1 training which will make TS1 contain the correct FTS count. Signed-off-by: Shawn Lin Signed-off-by: Bjorn Helgaas --- drivers/pci/host/pcie-rockchip.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c index 43b765e3ce80..b8c82fc812dc 100644 --- a/drivers/pci/host/pcie-rockchip.c +++ b/drivers/pci/host/pcie-rockchip.c @@ -95,6 +95,10 @@ #define PCIE_CORE_PL_CONF_SPEED_MASK 0x00000018 #define PCIE_CORE_PL_CONF_LANE_MASK 0x00000006 #define PCIE_CORE_PL_CONF_LANE_SHIFT 1 +#define PCIE_CORE_CTRL_PLC1 (PCIE_CORE_CTRL_MGMT_BASE + 0x004) +#define PCIE_CORE_CTRL_PLC1_FTS_MASK GENMASK(23, 8) +#define PCIE_CORE_CTRL_PLC1_FTS_SHIFT 8 +#define PCIE_CORE_CTRL_PLC1_FTS_CNT 0xffff #define PCIE_CORE_TXCREDIT_CFG1 (PCIE_CORE_CTRL_MGMT_BASE + 0x020) #define PCIE_CORE_TXCREDIT_CFG1_MUI_MASK 0xFFFF0000 #define PCIE_CORE_TXCREDIT_CFG1_MUI_SHIFT 16 @@ -486,6 +490,12 @@ static int rockchip_pcie_init_port(struct rockchip_pcie *rockchip) status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_L1_SUBSTATE_CTRL2); rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_L1_SUBSTATE_CTRL2); + /* Fix the transmitted FTS count desired to exit from L0s. */ + status = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL_PLC1); + status = (status & PCIE_CORE_CTRL_PLC1_FTS_MASK) | + (PCIE_CORE_CTRL_PLC1_FTS_CNT << PCIE_CORE_CTRL_PLC1_FTS_SHIFT); + rockchip_pcie_write(rockchip, status, PCIE_CORE_CTRL_PLC1); + /* Enable Gen1 training */ rockchip_pcie_write(rockchip, PCIE_CLIENT_LINK_TRAIN_ENABLE, PCIE_CLIENT_CONFIG); -- 2.20.1