From 9b3fe6796d7c0e0c2b87243ce0c7f4744c54efad Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Tue, 28 Mar 2017 08:42:49 -0700 Subject: PCI: imx6: Add code to support i.MX7D Add various bits of code needed to support i.MX7D variant of the IP. Signed-off-by: Andrey Smirnov Signed-off-by: Bjorn Helgaas Reviewed-by: Lucas Stach Acked-by: Lee Jones Acked-by: Rob Herring Cc: yurovsky@gmail.com Cc: Mark Rutland Cc: Fabio Estevam Cc: Dong Aisheng Cc: linux-arm-kernel@lists.infradead.org Cc: devicetree@vger.kernel.org --- drivers/pci/dwc/pci-imx6.c | 120 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 95 insertions(+), 25 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c index 801e46cd266d..e0c36d6f5a21 100644 --- a/drivers/pci/dwc/pci-imx6.c +++ b/drivers/pci/dwc/pci-imx6.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -27,6 +28,7 @@ #include #include #include +#include #include "pcie-designware.h" @@ -36,6 +38,7 @@ enum imx6_pcie_variants { IMX6Q, IMX6SX, IMX6QP, + IMX7D, }; struct imx6_pcie { @@ -47,6 +50,8 @@ struct imx6_pcie { struct clk *pcie_inbound_axi; struct clk *pcie; struct regmap *iomuxc_gpr; + struct reset_control *pciephy_reset; + struct reset_control *apps_reset; enum imx6_pcie_variants variant; u32 tx_deemph_gen1; u32 tx_deemph_gen2_3p5db; @@ -56,6 +61,11 @@ struct imx6_pcie { int link_gen; }; +/* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */ +#define PHY_PLL_LOCK_WAIT_MAX_RETRIES 2000 +#define PHY_PLL_LOCK_WAIT_USLEEP_MIN 50 +#define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200 + /* PCIe Root Complex registers (memory-mapped) */ #define PCIE_RC_LCR 0x7c #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1 @@ -248,6 +258,10 @@ static int imx6q_pcie_abort_handler(unsigned long addr, static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) { switch (imx6_pcie->variant) { + case IMX7D: + reset_control_assert(imx6_pcie->pciephy_reset); + reset_control_assert(imx6_pcie->apps_reset); + break; case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_TEST_POWERDOWN, @@ -303,11 +317,32 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie) regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16); break; + case IMX7D: + break; } return ret; } +static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie) +{ + u32 val; + unsigned int retries; + struct device *dev = imx6_pcie->pci->dev; + + for (retries = 0; retries < PHY_PLL_LOCK_WAIT_MAX_RETRIES; retries++) { + regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR22, &val); + + if (val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED) + return; + + usleep_range(PHY_PLL_LOCK_WAIT_USLEEP_MIN, + PHY_PLL_LOCK_WAIT_USLEEP_MAX); + } + + dev_err(dev, "PCIe PLL lock timeout\n"); +} + static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) { struct dw_pcie *pci = imx6_pcie->pci; @@ -351,6 +386,10 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) } switch (imx6_pcie->variant) { + case IMX7D: + reset_control_deassert(imx6_pcie->pciephy_reset); + imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie); + break; case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5, IMX6SX_GPR5_PCIE_BTNRST_RESET, 0); @@ -377,35 +416,44 @@ err_pcie_bus: static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie) { - if (imx6_pcie->variant == IMX6SX) + switch (imx6_pcie->variant) { + case IMX7D: + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, + IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0); + break; + case IMX6SX: regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6SX_GPR12_PCIE_RX_EQ_MASK, IMX6SX_GPR12_PCIE_RX_EQ_2); + /* FALLTHROUGH */ + default: + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, + IMX6Q_GPR12_PCIE_CTL_2, 0 << 10); - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, - IMX6Q_GPR12_PCIE_CTL_2, 0 << 10); + /* configure constant input signal to the pcie ctrl and phy */ + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, + IMX6Q_GPR12_LOS_LEVEL, 9 << 4); + + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, + IMX6Q_GPR8_TX_DEEMPH_GEN1, + imx6_pcie->tx_deemph_gen1 << 0); + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, + IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB, + imx6_pcie->tx_deemph_gen2_3p5db << 6); + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, + IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB, + imx6_pcie->tx_deemph_gen2_6db << 12); + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, + IMX6Q_GPR8_TX_SWING_FULL, + imx6_pcie->tx_swing_full << 18); + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, + IMX6Q_GPR8_TX_SWING_LOW, + imx6_pcie->tx_swing_low << 25); + break; + } - /* configure constant input signal to the pcie ctrl and phy */ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT << 12); - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, - IMX6Q_GPR12_LOS_LEVEL, 9 << 4); - - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, - IMX6Q_GPR8_TX_DEEMPH_GEN1, - imx6_pcie->tx_deemph_gen1 << 0); - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, - IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB, - imx6_pcie->tx_deemph_gen2_3p5db << 6); - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, - IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB, - imx6_pcie->tx_deemph_gen2_6db << 12); - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, - IMX6Q_GPR8_TX_SWING_FULL, - imx6_pcie->tx_swing_full << 18); - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8, - IMX6Q_GPR8_TX_SWING_LOW, - imx6_pcie->tx_swing_low << 25); } static int imx6_pcie_wait_for_link(struct imx6_pcie *imx6_pcie) @@ -469,8 +517,11 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp); /* Start LTSSM. */ - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, - IMX6Q_GPR12_PCIE_CTL_2, 1 << 10); + if (imx6_pcie->variant == IMX7D) + reset_control_deassert(imx6_pcie->apps_reset); + else + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, + IMX6Q_GPR12_PCIE_CTL_2, 1 << 10); ret = imx6_pcie_wait_for_link(imx6_pcie); if (ret) @@ -653,13 +704,31 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) return PTR_ERR(imx6_pcie->pcie); } - if (imx6_pcie->variant == IMX6SX) { + switch (imx6_pcie->variant) { + case IMX6SX: imx6_pcie->pcie_inbound_axi = devm_clk_get(dev, "pcie_inbound_axi"); if (IS_ERR(imx6_pcie->pcie_inbound_axi)) { dev_err(dev, "pcie_inbound_axi clock missing or invalid\n"); return PTR_ERR(imx6_pcie->pcie_inbound_axi); } + break; + case IMX7D: + imx6_pcie->pciephy_reset = devm_reset_control_get(dev, + "pciephy"); + if (IS_ERR(imx6_pcie->pciephy_reset)) { + dev_err(dev, "Failed to get PCIEPHY reset contol\n"); + return PTR_ERR(imx6_pcie->pciephy_reset); + } + + imx6_pcie->apps_reset = devm_reset_control_get(dev, "apps"); + if (IS_ERR(imx6_pcie->apps_reset)) { + dev_err(dev, "Failed to get PCIE APPS reset contol\n"); + return PTR_ERR(imx6_pcie->apps_reset); + } + break; + default: + break; } /* Grab GPR config register range */ @@ -718,6 +787,7 @@ static const struct of_device_id imx6_pcie_of_match[] = { { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, }, { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, }, { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, }, + { .compatible = "fsl,imx7d-pcie", .data = (void *)IMX7D, }, {}, }; -- cgit From bde4a5a00e761f55be92f62378cf5024ced79ee3 Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Tue, 28 Mar 2017 08:42:50 -0700 Subject: PCI: imx6: Allow probe deferral by reset GPIO Some designs implement reset GPIO via a GPIO expander connected to a peripheral bus. One such example would be i.MX7 Sabre board where said GPIO is provided by SPI shift register connected to a bitbanged SPI bus. To support such designs, allow reset GPIO request to defer probing of the driver. Signed-off-by: Andrey Smirnov Signed-off-by: Bjorn Helgaas Reviewed-by: Lucas Stach Cc: yurovsky@gmail.com Cc: Fabio Estevam Cc: Dong Aisheng Cc: linux-arm-kernel@lists.infradead.org --- drivers/pci/dwc/pci-imx6.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c index e0c36d6f5a21..d62ee3553cfe 100644 --- a/drivers/pci/dwc/pci-imx6.c +++ b/drivers/pci/dwc/pci-imx6.c @@ -595,8 +595,8 @@ static struct dw_pcie_host_ops imx6_pcie_host_ops = { .host_init = imx6_pcie_host_init, }; -static int __init imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, - struct platform_device *pdev) +static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, + struct platform_device *pdev) { struct dw_pcie *pci = imx6_pcie->pci; struct pcie_port *pp = &pci->pp; @@ -636,7 +636,7 @@ static const struct dw_pcie_ops dw_pcie_ops = { .link_up = imx6_pcie_link_up, }; -static int __init imx6_pcie_probe(struct platform_device *pdev) +static int imx6_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct dw_pcie *pci; @@ -660,10 +660,6 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) imx6_pcie->variant = (enum imx6_pcie_variants)of_device_get_match_data(dev); - /* Added for PCI abort handling */ - hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, - "imprecise external abort"); - dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); pci->dbi_base = devm_ioremap_resource(dev, dbi_base); if (IS_ERR(pci->dbi_base)) @@ -683,6 +679,8 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) dev_err(dev, "unable to get reset gpio\n"); return ret; } + } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) { + return imx6_pcie->reset_gpio; } /* Fetch clocks */ @@ -796,11 +794,22 @@ static struct platform_driver imx6_pcie_driver = { .name = "imx6q-pcie", .of_match_table = imx6_pcie_of_match, }, + .probe = imx6_pcie_probe, .shutdown = imx6_pcie_shutdown, }; static int __init imx6_pcie_init(void) { - return platform_driver_probe(&imx6_pcie_driver, imx6_pcie_probe); + /* + * Since probe() can be deferred we need to make sure that + * hook_fault_code is not called after __init memory is freed + * by kernel and since imx6q_pcie_abort_handler() is a no-op, + * we can install the handler here without risking it + * accessing some uninitialized driver state. + */ + hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, + "imprecise external abort"); + + return platform_driver_register(&imx6_pcie_driver); } device_initcall(imx6_pcie_init); -- cgit From e6dcd87fff69a9d454104b65569074855cf95b1e Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Tue, 28 Mar 2017 08:42:51 -0700 Subject: PCI: imx6: Do not wait for speed change on i.MX7 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As can be seen from [1]: "...the different behavior between iMX6Q PCIe and iMX7D PCIe maybe caused by the different controller version. Regarding to the DOC description, the DIRECT_SPEED_CHANGE should be cleared after the speed change from GEN1 to GEN2. Unfortunately, when GEN1 device is used, the behavior is not documented. So, IC design guys run the simulation and find out the following behaviors: 1. DIRECT_SPEED_CHANGE will be cleared in 7D after speed change from GEN1 to GEN2. This matches doc’s description 2. set MAX link speed(PCIE_CAP_TARGET_LINK_SPEED=0x01) as GEN1 and re-run the simulation, DIRECT_SPEED_CHANGE will not be cleared; remain as 1, this matches your result, but function test is passed, so this bit should not affect the normal PCIe function." imx6_pcie_wait_for_speed_change() will report false failures for Gen1 -> Gen1 speed transition, so avoid doing that check and just rely on imx6_pcie_wait_for_link() only. [1] https://community.nxp.com/message/867943 Signed-off-by: Andrey Smirnov Signed-off-by: Bjorn Helgaas Reviewed-by: Lucas Stach Cc: yurovsky@gmail.com Cc: Fabio Estevam Cc: Dong Aisheng Cc: linux-arm-kernel@lists.infradead.org --- drivers/pci/dwc/pci-imx6.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c index d62ee3553cfe..793b008553a0 100644 --- a/drivers/pci/dwc/pci-imx6.c +++ b/drivers/pci/dwc/pci-imx6.c @@ -545,10 +545,21 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) tmp |= PORT_LOGIC_SPEED_CHANGE; dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp); - ret = imx6_pcie_wait_for_speed_change(imx6_pcie); - if (ret) { - dev_err(dev, "Failed to bring link up!\n"); - goto err_reset_phy; + if (imx6_pcie->variant != IMX7D) { + /* + * On i.MX7, DIRECT_SPEED_CHANGE behaves differently + * from i.MX6 family when no link speed transition + * occurs and we go Gen1 -> yep, Gen1. The difference + * is that, in such case, it will not be cleared by HW + * which will cause the following code to report false + * failure. + */ + + ret = imx6_pcie_wait_for_speed_change(imx6_pcie); + if (ret) { + dev_err(dev, "Failed to bring link up!\n"); + goto err_reset_phy; + } } /* Make sure link training is finished as well! */ -- cgit From 93b226f9c65a951a91617f87ba1f05f14e59f26f Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Tue, 28 Mar 2017 08:42:52 -0700 Subject: PCI: imx6: Do not switch speed if Gen2 is disabled Save a bit of time and avoid going through link speed change procedure in configuration where link max speed is limited to Gen1 in DT. Signed-off-by: Andrey Smirnov Signed-off-by: Bjorn Helgaas Reviewed-by: Lucas Stach Cc: yurovsky@gmail.com Cc: Fabio Estevam Cc: Dong Aisheng Cc: linux-arm-kernel@lists.infradead.org --- drivers/pci/dwc/pci-imx6.c | 52 +++++++++++++++++++++++----------------------- 1 file changed, 26 insertions(+), 26 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c index 793b008553a0..102edcf1e261 100644 --- a/drivers/pci/dwc/pci-imx6.c +++ b/drivers/pci/dwc/pci-imx6.c @@ -533,40 +533,40 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK; tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2; dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp); - } else { - dev_info(dev, "Link: Gen2 disabled\n"); - } - - /* - * Start Directed Speed Change so the best possible speed both link - * partners support can be negotiated. - */ - tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); - tmp |= PORT_LOGIC_SPEED_CHANGE; - dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp); - if (imx6_pcie->variant != IMX7D) { /* - * On i.MX7, DIRECT_SPEED_CHANGE behaves differently - * from i.MX6 family when no link speed transition - * occurs and we go Gen1 -> yep, Gen1. The difference - * is that, in such case, it will not be cleared by HW - * which will cause the following code to report false - * failure. + * Start Directed Speed Change so the best possible + * speed both link partners support can be negotiated. */ + tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL); + tmp |= PORT_LOGIC_SPEED_CHANGE; + dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp); + + if (imx6_pcie->variant != IMX7D) { + /* + * On i.MX7, DIRECT_SPEED_CHANGE behaves differently + * from i.MX6 family when no link speed transition + * occurs and we go Gen1 -> yep, Gen1. The difference + * is that, in such case, it will not be cleared by HW + * which will cause the following code to report false + * failure. + */ + + ret = imx6_pcie_wait_for_speed_change(imx6_pcie); + if (ret) { + dev_err(dev, "Failed to bring link up!\n"); + goto err_reset_phy; + } + } - ret = imx6_pcie_wait_for_speed_change(imx6_pcie); + /* Make sure link training is finished as well! */ + ret = imx6_pcie_wait_for_link(imx6_pcie); if (ret) { dev_err(dev, "Failed to bring link up!\n"); goto err_reset_phy; } - } - - /* Make sure link training is finished as well! */ - ret = imx6_pcie_wait_for_link(imx6_pcie); - if (ret) { - dev_err(dev, "Failed to bring link up!\n"); - goto err_reset_phy; + } else { + dev_info(dev, "Link: Gen2 disabled\n"); } tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCSR); -- cgit From 7221547e55b7929e4d46983f6f3ca15f36ee4dac Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Fri, 21 Apr 2017 08:02:30 +0100 Subject: PCI: imx6: Fix spelling mistake: "contol" -> "control" Trivial fix to spelling mistake in dev_err message Signed-off-by: Colin Ian King Signed-off-by: Bjorn Helgaas Acked-by: Richard Zhu --- drivers/pci/dwc/pci-imx6.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c index 102edcf1e261..129717ae5022 100644 --- a/drivers/pci/dwc/pci-imx6.c +++ b/drivers/pci/dwc/pci-imx6.c @@ -726,13 +726,13 @@ static int imx6_pcie_probe(struct platform_device *pdev) imx6_pcie->pciephy_reset = devm_reset_control_get(dev, "pciephy"); if (IS_ERR(imx6_pcie->pciephy_reset)) { - dev_err(dev, "Failed to get PCIEPHY reset contol\n"); + dev_err(dev, "Failed to get PCIEPHY reset control\n"); return PTR_ERR(imx6_pcie->pciephy_reset); } imx6_pcie->apps_reset = devm_reset_control_get(dev, "apps"); if (IS_ERR(imx6_pcie->apps_reset)) { - dev_err(dev, "Failed to get PCIE APPS reset contol\n"); + dev_err(dev, "Failed to get PCIE APPS reset control\n"); return PTR_ERR(imx6_pcie->apps_reset); } break; -- cgit