From 191cd6fb5d2cf184a3010c55ca290b2fe5a3d727 Mon Sep 17 00:00:00 2001 From: Manikanta Maddireddy Date: Tue, 18 Jun 2019 23:31:53 +0530 Subject: [PATCH] PCI: tegra: Add SW fixup for RAW violations The logic which blocks read requests till AFI gets ACK for all outstanding writes from memory controller does not behave correctly when number of outstanding writes become more than 32 in Tegra124 and Tegra132. SW fixup is to prevent writes from accumulating more than 32 by: - limiting outstanding posted writes to 14 - modifying Gen1 and Gen2 UpdateFC timer frequency UpdateFC timer frequency is equal to twice the value of register content in nsec. These settings are recommended after stress testing with different values. Signed-off-by: Manikanta Maddireddy Signed-off-by: Lorenzo Pieralisi Acked-by: Thierry Reding --- drivers/pci/controller/pci-tegra.c | 34 ++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index 609edcb45f47..95e27c08e8bd 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -178,6 +178,13 @@ #define AFI_PEXBIAS_CTRL_0 0x168 +#define RP_PRIV_XP_DL 0x00000494 +#define RP_PRIV_XP_DL_GEN2_UPD_FC_TSHOLD (0x1ff << 1) + +#define RP_RX_HDR_LIMIT 0x00000e00 +#define RP_RX_HDR_LIMIT_PW_MASK (0xff << 8) +#define RP_RX_HDR_LIMIT_PW (0x0e << 8) + #define RP_ECTL_2_R1 0x00000e84 #define RP_ECTL_2_R1_RX_CTLE_1C_MASK 0xffff @@ -208,6 +215,7 @@ #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_XP_UPDATE_FC_THRESHOLD_MASK (0xff << 18) #define RP_VEND_CTL0 0x00000f44 #define RP_VEND_CTL0_DSK_RST_PULSE_WIDTH_MASK (0xf << 12) @@ -301,6 +309,7 @@ struct tegra_pcie_soc { u32 tx_ref_sel; u32 pads_refclk_cfg0; u32 pads_refclk_cfg1; + u32 update_fc_threshold; bool has_pex_clkreq_en; bool has_pex_bias_ctrl; bool has_intr_prsnt_sense; @@ -310,6 +319,7 @@ struct tegra_pcie_soc { bool program_uphy; bool update_clamp_threshold; bool program_deskew_time; + bool raw_violation_fixup; struct { struct { u32 rp_ectl_2_r1; @@ -641,6 +651,23 @@ static void tegra_pcie_apply_sw_fixup(struct tegra_pcie_port *port) value |= RP_VEND_CTL0_DSK_RST_PULSE_WIDTH; writel(value, port->base + RP_VEND_CTL0); } + + /* Fixup for read after write violation. */ + if (soc->raw_violation_fixup) { + value = readl(port->base + RP_RX_HDR_LIMIT); + value &= ~RP_RX_HDR_LIMIT_PW_MASK; + value |= RP_RX_HDR_LIMIT_PW; + writel(value, port->base + RP_RX_HDR_LIMIT); + + value = readl(port->base + RP_PRIV_XP_DL); + value |= RP_PRIV_XP_DL_GEN2_UPD_FC_TSHOLD; + writel(value, port->base + RP_PRIV_XP_DL); + + value = readl(port->base + RP_VEND_XP); + value &= ~RP_VEND_XP_UPDATE_FC_THRESHOLD_MASK; + value |= soc->update_fc_threshold; + writel(value, port->base + RP_VEND_XP); + } } static void tegra_pcie_port_enable(struct tegra_pcie_port *port) @@ -2401,6 +2428,7 @@ static const struct tegra_pcie_soc tegra20_pcie = { .program_uphy = true, .update_clamp_threshold = false, .program_deskew_time = false, + .raw_violation_fixup = false, .ectl.enable = false, }; @@ -2427,6 +2455,7 @@ static const struct tegra_pcie_soc tegra30_pcie = { .program_uphy = true, .update_clamp_threshold = false, .program_deskew_time = false, + .raw_violation_fixup = false, .ectl.enable = false, }; @@ -2437,6 +2466,8 @@ static const struct tegra_pcie_soc tegra124_pcie = { .pads_pll_ctl = PADS_PLL_CTL_TEGRA30, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_BUF_EN, .pads_refclk_cfg0 = 0x44ac44ac, + /* FC threshold is bit[25:18] */ + .update_fc_threshold = 0x03fc0000, .has_pex_clkreq_en = true, .has_pex_bias_ctrl = true, .has_intr_prsnt_sense = true, @@ -2446,6 +2477,7 @@ static const struct tegra_pcie_soc tegra124_pcie = { .program_uphy = true, .update_clamp_threshold = true, .program_deskew_time = false, + .raw_violation_fixup = true, .ectl.enable = false, }; @@ -2465,6 +2497,7 @@ static const struct tegra_pcie_soc tegra210_pcie = { .program_uphy = true, .update_clamp_threshold = true, .program_deskew_time = true, + .raw_violation_fixup = false, .ectl = { .regs = { .rp_ectl_2_r1 = 0x0000000f, @@ -2503,6 +2536,7 @@ static const struct tegra_pcie_soc tegra186_pcie = { .program_uphy = false, .update_clamp_threshold = false, .program_deskew_time = false, + .raw_violation_fixup = false, .ectl.enable = false, }; -- 2.30.2