diff options
Diffstat (limited to 'drivers/pci/host/pci-imx6.c')
| -rw-r--r-- | drivers/pci/host/pci-imx6.c | 137 |
1 files changed, 54 insertions, 83 deletions
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index fe600964fa50..bd3f7d0ef943 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -202,6 +202,23 @@ static int pcie_phy_write(void __iomem *dbi_base, int addr, int data) return 0; } +static void imx6_pcie_reset_phy(struct pcie_port *pp) +{ + u32 tmp; + + pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &tmp); + tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN | + PHY_RX_OVRD_IN_LO_RX_PLL_EN); + pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, tmp); + + usleep_range(2000, 3000); + + pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &tmp); + tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN | + PHY_RX_OVRD_IN_LO_RX_PLL_EN); + pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, tmp); +} + /* Added for PCI abort handling */ static int imx6q_pcie_abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs) @@ -332,16 +349,30 @@ static int imx6_pcie_wait_for_link(struct pcie_port *pp) { unsigned int retries; + /* + * Test if the PHY reports that the link is up and also that the LTSSM + * training finished. There are three possible states of the link when + * this code is called: + * 1) The link is DOWN (unlikely) + * The link didn't come up yet for some reason. This usually means + * we have a real problem somewhere, if it happens with a peripheral + * connected. This state calls for inspection of the DEBUG registers. + * 2) The link is UP, but still in LTSSM training + * Wait for the training to finish, which should take a very short + * time. If the training does not finish, we have a problem and we + * need to inspect the DEBUG registers. If the training does finish, + * the link is up and operating correctly. + * 3) The link is UP and no longer in LTSSM training + * The link is up and operating correctly. + */ for (retries = 0; retries < 200; retries++) { - if (dw_pcie_link_up(pp)) + u32 reg = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1); + if ((reg & PCIE_PHY_DEBUG_R1_XMLH_LINK_UP) && + !(reg & PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING)) return 0; - usleep_range(100, 1000); + usleep_range(1000, 2000); } - dev_err(pp->dev, "phy link never came up\n"); - dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n", - readl(pp->dbi_base + PCIE_PHY_DEBUG_R0), - readl(pp->dbi_base + PCIE_PHY_DEBUG_R1)); return -EINVAL; } @@ -390,8 +421,10 @@ static int imx6_pcie_establish_link(struct pcie_port *pp) IMX6Q_GPR12_PCIE_CTL_2, 1 << 10); ret = imx6_pcie_wait_for_link(pp); - if (ret) - return ret; + if (ret) { + dev_info(pp->dev, "Link never came up\n"); + goto err_reset_phy; + } /* Allow Gen2 mode after the link is up. */ tmp = readl(pp->dbi_base + PCIE_RC_LCR); @@ -410,19 +443,28 @@ static int imx6_pcie_establish_link(struct pcie_port *pp) ret = imx6_pcie_wait_for_speed_change(pp); if (ret) { dev_err(pp->dev, "Failed to bring link up!\n"); - return ret; + goto err_reset_phy; } /* Make sure link training is finished as well! */ ret = imx6_pcie_wait_for_link(pp); if (ret) { dev_err(pp->dev, "Failed to bring link up!\n"); - return ret; + goto err_reset_phy; } tmp = readl(pp->dbi_base + PCIE_RC_LCSR); dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf); + return 0; + +err_reset_phy: + dev_dbg(pp->dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n", + readl(pp->dbi_base + PCIE_PHY_DEBUG_R0), + readl(pp->dbi_base + PCIE_PHY_DEBUG_R1)); + imx6_pcie_reset_phy(pp); + + return ret; } static void imx6_pcie_host_init(struct pcie_port *pp) @@ -441,81 +483,10 @@ static void imx6_pcie_host_init(struct pcie_port *pp) dw_pcie_msi_init(pp); } -static void imx6_pcie_reset_phy(struct pcie_port *pp) -{ - u32 tmp; - - pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &tmp); - tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN | - PHY_RX_OVRD_IN_LO_RX_PLL_EN); - pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, tmp); - - usleep_range(2000, 3000); - - pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &tmp); - tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN | - PHY_RX_OVRD_IN_LO_RX_PLL_EN); - pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, tmp); -} - static int imx6_pcie_link_up(struct pcie_port *pp) { - u32 rc, debug_r0, rx_valid; - int count = 5; - - /* - * Test if the PHY reports that the link is up and also that the LTSSM - * training finished. There are three possible states of the link when - * this code is called: - * 1) The link is DOWN (unlikely) - * The link didn't come up yet for some reason. This usually means - * we have a real problem somewhere. Reset the PHY and exit. This - * state calls for inspection of the DEBUG registers. - * 2) The link is UP, but still in LTSSM training - * Wait for the training to finish, which should take a very short - * time. If the training does not finish, we have a problem and we - * need to inspect the DEBUG registers. If the training does finish, - * the link is up and operating correctly. - * 3) The link is UP and no longer in LTSSM training - * The link is up and operating correctly. - */ - while (1) { - rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1); - if (!(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_UP)) - break; - if (!(rc & PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING)) - return 1; - if (!count--) - break; - dev_dbg(pp->dev, "Link is up, but still in training\n"); - /* - * Wait a little bit, then re-check if the link finished - * the training. - */ - usleep_range(1000, 2000); - } - /* - * From L0, initiate MAC entry to gen2 if EP/RC supports gen2. - * Wait 2ms (LTSSM timeout is 24ms, PHY lock is ~5us in gen2). - * If (MAC/LTSSM.state == Recovery.RcvrLock) - * && (PHY/rx_valid==0) then pulse PHY/rx_reset. Transition - * to gen2 is stuck - */ - pcie_phy_read(pp->dbi_base, PCIE_PHY_RX_ASIC_OUT, &rx_valid); - debug_r0 = readl(pp->dbi_base + PCIE_PHY_DEBUG_R0); - - if (rx_valid & PCIE_PHY_RX_ASIC_OUT_VALID) - return 0; - - if ((debug_r0 & 0x3f) != 0x0d) - return 0; - - dev_err(pp->dev, "transition to gen2 is stuck, reset PHY!\n"); - dev_dbg(pp->dev, "debug_r0=%08x debug_r1=%08x\n", debug_r0, rc); - - imx6_pcie_reset_phy(pp); - - return 0; + return readl(pp->dbi_base + PCIE_PHY_DEBUG_R1) & + PCIE_PHY_DEBUG_R1_XMLH_LINK_UP; } static struct pcie_host_ops imx6_pcie_host_ops = { |