From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net ([212.18.0.10]:38664 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932499Ab3KZVLT (ORCPT ); Tue, 26 Nov 2013 16:11:19 -0500 From: Marek Vasut To: linux-arm-kernel@lists.infradead.org Cc: linux-pci@vger.kernel.org, Marek Vasut , Bjorn Helgaas , Frank Li , Harro Haan , Jingoo Han , Mohit KUMAR , Pratyush Anand , Richard Zhu , Sascha Hauer , Sean Cross , Shawn Guo , Siva Reddy Kallam , Srikanth T Shivanand , Tim Harvey , Troy Kisky , Yinghai Lu Subject: [PATCH 3/7] PCI: imx6: Fix waiting for link up Date: Tue, 26 Nov 2013 22:10:44 +0100 Message-Id: <1385500248-6551-3-git-send-email-marex@denx.de> In-Reply-To: <1385500248-6551-1-git-send-email-marex@denx.de> References: <1385500248-6551-1-git-send-email-marex@denx.de> Sender: linux-pci-owner@vger.kernel.org List-ID: While waiting for the PHY to report the PCIe link is up, we might hit a situation where the link training is still in progress, while the PHY already reports the link is up. Add additional check for this condition. Signed-off-by: Marek Vasut Cc: Bjorn Helgaas Cc: Frank Li Cc: Harro Haan Cc: Jingoo Han Cc: Mohit KUMAR Cc: Pratyush Anand Cc: Richard Zhu Cc: Sascha Hauer Cc: Sean Cross Cc: Shawn Guo Cc: Siva Reddy Kallam Cc: Srikanth T Shivanand Cc: Tim Harvey Cc: Troy Kisky Cc: Yinghai Lu --- drivers/pci/host/pci-imx6.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index 52027ad..4d5be4e 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -48,6 +48,8 @@ struct imx6_pcie { #define PL_OFFSET 0x700 #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28) #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c) +#define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING (1 << 29) +#define PCIE_PHY_DEBUG_R1_XMLH_LINK_UP (1 << 4) #define PCIE_PHY_CTRL (PL_OFFSET + 0x114) #define PCIE_PHY_CTRL_DATA_LOC 0 @@ -338,10 +340,17 @@ static int imx6_pcie_link_up(struct pcie_port *pp) { u32 rc, ltssm, rx_valid, temp; - /* link is debug bit 36, debug register 1 starts at bit 32 */ - rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1) & (0x1 << (36 - 32)); - if (rc) - return -EAGAIN; + /* + * Test if the PHY reports that the link is up and also that + * the link training finished. It might happen that the PHY + * reports the link is already up, but the link training bit + * is still set, so make sure to check the training is done + * as well here. + */ + rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1); + if ((rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_UP) && + !(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING)) + return 1; /* * From L0, initiate MAC entry to gen2 if EP/RC supports gen2. -- 1.8.4.3