From mboxrd@z Thu Jan 1 00:00:00 1970 From: Manikanta Maddireddy Subject: [PATCH V3 08/12] PCI: tegra: Wait for DLLP to finish before entering L1 or L2 Date: Mon, 30 Oct 2017 19:27:19 +0530 Message-ID: <1509371843-22931-9-git-send-email-mmaddireddy@nvidia.com> References: <1509371843-22931-1-git-send-email-mmaddireddy@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1509371843-22931-1-git-send-email-mmaddireddy@nvidia.com> Sender: linux-pci-owner@vger.kernel.org To: thierry.reding@gmail.com, bhelgaas@google.com, jonathanh@nvidia.com, vidyas@nvidia.com, mperttunen@nvidia.com Cc: linux-tegra@vger.kernel.org, linux-pci@vger.kernel.org, kthota@nvidia.com, Manikanta Maddireddy List-Id: linux-tegra@vger.kernel.org Set required bit to have LTSSM wait for DLLP to finish before entering L1 or L2. This avoids truncation of PM messages which results in receiver errors. Signed-off-by: Manikanta Maddireddy --- V3: * no change in this patch V2: * no change in this patch drivers/pci/host/pci-tegra.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c index c264037112cb..34740a7033f7 100644 --- a/drivers/pci/host/pci-tegra.c +++ b/drivers/pci/host/pci-tegra.c @@ -219,6 +219,9 @@ #define RP_VEND_CTL1 0xf48 #define RP_VEND_CTL1_ERPT (1 << 13) +#define RP_VEND_XP_BIST 0xf4c +#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) @@ -2162,6 +2165,13 @@ static void tegra_pcie_apply_sw_fixup(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); } /* * FIXME: If there are no PCIe cards attached, then calling this function -- 2.1.4