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path: root/drivers/pci/dwc/pci-imx6.c
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Diffstat (limited to 'drivers/pci/dwc/pci-imx6.c')
-rw-r--r--drivers/pci/dwc/pci-imx6.c199
1 files changed, 145 insertions, 54 deletions
diff --git a/drivers/pci/dwc/pci-imx6.c b/drivers/pci/dwc/pci-imx6.c
index 801e46cd266d..a98cba55c7f0 100644
--- a/drivers/pci/dwc/pci-imx6.c
+++ b/drivers/pci/dwc/pci-imx6.c
@@ -17,6 +17,7 @@
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
+#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
#include <linux/module.h>
#include <linux/of_gpio.h>
#include <linux/of_device.h>
@@ -27,6 +28,7 @@
#include <linux/signal.h>
#include <linux/types.h>
#include <linux/interrupt.h>
+#include <linux/reset.h>
#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)
@@ -482,29 +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);
- ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
- if (ret) {
- dev_err(dev, "Failed to bring link up!\n");
- goto err_reset_phy;
- }
+ /*
+ * 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;
+ }
+ }
- /* 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);
@@ -544,8 +606,8 @@ 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;
@@ -585,7 +647,7 @@ 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;
@@ -609,10 +671,6 @@ 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))
@@ -632,6 +690,8 @@ 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 */
@@ -653,13 +713,31 @@ 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 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 control\n");
+ return PTR_ERR(imx6_pcie->apps_reset);
+ }
+ break;
+ default:
+ break;
}
/* Grab GPR config register range */
@@ -718,6 +796,7 @@ 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, },
{},
};
@@ -725,12 +804,24 @@ static struct platform_driver imx6_pcie_driver = {
.driver = {
.name = "imx6q-pcie",
.of_match_table = imx6_pcie_of_match,
+ .suppress_bind_attrs = true,
},
+ .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);