From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Manikanta Maddireddy Subject: [PATCH V4 11/28] PCI: tegra: Process pending DLL transactions before entering L1 or L2 Date: Thu, 16 May 2019 11:22:50 +0530 Message-ID: <20190516055307.25737-12-mmaddireddy@nvidia.com> In-Reply-To: <20190516055307.25737-1-mmaddireddy@nvidia.com> References: <20190516055307.25737-1-mmaddireddy@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain 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: PM message are truncated while entering L1 or L2, which is resulting in receiver errors. Set the required bit to finish processing DLLP before link enter L1 or L2. Signed-off-by: Manikanta Maddireddy Acked-by: Thierry Reding --- V4: No change V3: No change V2: No change drivers/pci/controller/pci-tegra.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index 17c6d858ddc6..d3da03a10e04 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -212,6 +212,9 @@ #define RP_VEND_CTL1 0x00000f48 #define RP_VEND_CTL1_ERPT (1 << 13) +#define RP_VEND_XP_BIST 0x00000f4c +#define RP_VEND_XP_BIST_GOTO_L1_L2_AFTER_DLLP_DONE (1 << 28) + #define RP_VEND_CTL2 0x00000fa8 #define RP_VEND_CTL2_PCA_ENABLE (1 << 7) @@ -538,6 +541,14 @@ static void tegra_pcie_enable_rp_features(struct tegra_pcie_port *port) value |= RP_VEND_XP_OPPORTUNISTIC_ACK; value |= RP_VEND_XP_OPPORTUNISTIC_UPDATEFC; writel(value, port->base + RP_VEND_XP); + + /* + * LTSSM will wait for DLLP to finish before entering L1 or L2, + * to avoid truncation of PM messages which results in receiver errors + */ + value = readl(port->base + RP_VEND_XP_BIST); + value |= RP_VEND_XP_BIST_GOTO_L1_L2_AFTER_DLLP_DONE; + writel(value, port->base + RP_VEND_XP_BIST); } static void tegra_pcie_program_ectl_settings(struct tegra_pcie_port *port) -- 2.17.1