From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from hqemgate14.nvidia.com ([216.228.121.143]:8362 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729337AbfFRSDG (ORCPT ); Tue, 18 Jun 2019 14:03:06 -0400 From: Manikanta Maddireddy Subject: [PATCH V6 15/27] PCI: tegra: Update flow control timer frequency in Tegra210 Date: Tue, 18 Jun 2019 23:31:54 +0530 Message-ID: <20190618180206.4908-16-mmaddireddy@nvidia.com> In-Reply-To: <20190618180206.4908-1-mmaddireddy@nvidia.com> References: <20190618180206.4908-1-mmaddireddy@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain Sender: devicetree-owner@vger.kernel.org To: thierry.reding@gmail.com, bhelgaas@google.com, robh+dt@kernel.org, mark.rutland@arm.com, jonathanh@nvidia.com, lorenzo.pieralisi@arm.com, vidyas@nvidia.com Cc: linux-tegra@vger.kernel.org, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, Manikanta Maddireddy List-ID: Recommended UpdateFC threshold in Tegra210 is 0x60 for best performance of x1 link. Setting this to 0x60 provides the best balance between number of UpdateFC packets and read data sent over the link. UpdateFC timer frequency is equal to twice the value of register content in nsec, i.e (2 * 0x60) = 192 nsec. Signed-off-by: Manikanta Maddireddy Acked-by: Thierry Reding --- V6: No change V5: No change V4: No change V3: No change V2: Changed update_fc_val to update_fc_threshold drivers/pci/controller/pci-tegra.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index 70bfbb7930c8..6ed406c46409 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -320,6 +320,7 @@ struct tegra_pcie_soc { bool update_clamp_threshold; bool program_deskew_time; bool raw_violation_fixup; + bool update_fc_timer; struct { struct { u32 rp_ectl_2_r1; @@ -668,6 +669,13 @@ static void tegra_pcie_apply_sw_fixup(struct tegra_pcie_port *port) value |= soc->update_fc_threshold; writel(value, port->base + RP_VEND_XP); } + + if (soc->update_fc_timer) { + 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) @@ -2410,6 +2418,7 @@ static const struct tegra_pcie_soc tegra20_pcie = { .update_clamp_threshold = false, .program_deskew_time = false, .raw_violation_fixup = false, + .update_fc_timer = false, .ectl.enable = false, }; @@ -2437,6 +2446,7 @@ static const struct tegra_pcie_soc tegra30_pcie = { .update_clamp_threshold = false, .program_deskew_time = false, .raw_violation_fixup = false, + .update_fc_timer = false, .ectl.enable = false, }; @@ -2459,6 +2469,7 @@ static const struct tegra_pcie_soc tegra124_pcie = { .update_clamp_threshold = true, .program_deskew_time = false, .raw_violation_fixup = true, + .update_fc_timer = false, .ectl.enable = false, }; @@ -2469,6 +2480,8 @@ static const struct tegra_pcie_soc tegra210_pcie = { .pads_pll_ctl = PADS_PLL_CTL_TEGRA30, .tx_ref_sel = PADS_PLL_CTL_TXCLKREF_BUF_EN, .pads_refclk_cfg0 = 0x90b890b8, + /* FC threshold is bit[25:18] */ + .update_fc_threshold = 0x01800000, .has_pex_clkreq_en = true, .has_pex_bias_ctrl = true, .has_intr_prsnt_sense = true, @@ -2479,6 +2492,7 @@ static const struct tegra_pcie_soc tegra210_pcie = { .update_clamp_threshold = true, .program_deskew_time = true, .raw_violation_fixup = false, + .update_fc_timer = true, .ectl = { .regs = { .rp_ectl_2_r1 = 0x0000000f, @@ -2518,6 +2532,7 @@ static const struct tegra_pcie_soc tegra186_pcie = { .update_clamp_threshold = false, .program_deskew_time = false, .raw_violation_fixup = false, + .update_fc_timer = false, .ectl.enable = false, }; -- 2.17.1