--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe Gen4 host controller driver for NXP Layerscape SoCs
+ *
+ * Copyright 2019-2020 NXP
+ *
+ * Author: Zhiqiang Hou <Zhiqiang.Hou@nxp.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "pcie-mobiveil.h"
+
+/* LUT and PF control registers */
+#define PCIE_LUT_OFF 0x80000
+#define PCIE_PF_OFF 0xc0000
+#define PCIE_PF_INT_STAT 0x18
+#define PF_INT_STAT_PABRST BIT(31)
+
+#define PCIE_PF_DBG 0x7fc
+#define PF_DBG_LTSSM_MASK 0x3f
+#define PF_DBG_LTSSM_L0 0x2d /* L0 state */
+#define PF_DBG_WE BIT(31)
+#define PF_DBG_PABR BIT(27)
+
+#define to_ls_pcie_g4(x) platform_get_drvdata((x)->pdev)
+
+struct ls_pcie_g4 {
+ struct mobiveil_pcie pci;
+ struct delayed_work dwork;
+ int irq;
+};
+
+static inline u32 ls_pcie_g4_lut_readl(struct ls_pcie_g4 *pcie, u32 off)
+{
+ return ioread32(pcie->pci.csr_axi_slave_base + PCIE_LUT_OFF + off);
+}
+
+static inline void ls_pcie_g4_lut_writel(struct ls_pcie_g4 *pcie,
+ u32 off, u32 val)
+{
+ iowrite32(val, pcie->pci.csr_axi_slave_base + PCIE_LUT_OFF + off);
+}
+
+static inline u32 ls_pcie_g4_pf_readl(struct ls_pcie_g4 *pcie, u32 off)
+{
+ return ioread32(pcie->pci.csr_axi_slave_base + PCIE_PF_OFF + off);
+}
+
+static inline void ls_pcie_g4_pf_writel(struct ls_pcie_g4 *pcie,
+ u32 off, u32 val)
+{
+ iowrite32(val, pcie->pci.csr_axi_slave_base + PCIE_PF_OFF + off);
+}
+
+static int ls_pcie_g4_link_up(struct mobiveil_pcie *pci)
+{
+ struct ls_pcie_g4 *pcie = to_ls_pcie_g4(pci);
+ u32 state;
+
+ state = ls_pcie_g4_pf_readl(pcie, PCIE_PF_DBG);
+ state = state & PF_DBG_LTSSM_MASK;
+
+ if (state == PF_DBG_LTSSM_L0)
+ return 1;
+
+ return 0;
+}
+
+static void ls_pcie_g4_disable_interrupt(struct ls_pcie_g4 *pcie)
+{
+ struct mobiveil_pcie *mv_pci = &pcie->pci;
+
+ mobiveil_csr_writel(mv_pci, 0, PAB_INTP_AMBA_MISC_ENB);
+}
+
+static void ls_pcie_g4_enable_interrupt(struct ls_pcie_g4 *pcie)
+{
+ struct mobiveil_pcie *mv_pci = &pcie->pci;
+ u32 val;
+
+ /* Clear the interrupt status */
+ mobiveil_csr_writel(mv_pci, 0xffffffff, PAB_INTP_AMBA_MISC_STAT);
+
+ val = PAB_INTP_INTX_MASK | PAB_INTP_MSI | PAB_INTP_RESET |
+ PAB_INTP_PCIE_UE | PAB_INTP_IE_PMREDI | PAB_INTP_IE_EC;
+ mobiveil_csr_writel(mv_pci, val, PAB_INTP_AMBA_MISC_ENB);
+}
+
+static int ls_pcie_g4_reinit_hw(struct ls_pcie_g4 *pcie)
+{
+ struct mobiveil_pcie *mv_pci = &pcie->pci;
+ struct device *dev = &mv_pci->pdev->dev;
+ u32 val, act_stat;
+ int to = 100;
+
+ /* Poll for pab_csb_reset to set and PAB activity to clear */
+ do {
+ usleep_range(10, 15);
+ val = ls_pcie_g4_pf_readl(pcie, PCIE_PF_INT_STAT);
+ act_stat = mobiveil_csr_readl(mv_pci, PAB_ACTIVITY_STAT);
+ } while (((val & PF_INT_STAT_PABRST) == 0 || act_stat) && to--);
+ if (to < 0) {
+ dev_err(dev, "Poll PABRST&PABACT timeout\n");
+ return -EIO;
+ }
+
+ /* clear PEX_RESET bit in PEX_PF0_DBG register */
+ val = ls_pcie_g4_pf_readl(pcie, PCIE_PF_DBG);
+ val |= PF_DBG_WE;
+ ls_pcie_g4_pf_writel(pcie, PCIE_PF_DBG, val);
+
+ val = ls_pcie_g4_pf_readl(pcie, PCIE_PF_DBG);
+ val |= PF_DBG_PABR;
+ ls_pcie_g4_pf_writel(pcie, PCIE_PF_DBG, val);
+
+ val = ls_pcie_g4_pf_readl(pcie, PCIE_PF_DBG);
+ val &= ~PF_DBG_WE;
+ ls_pcie_g4_pf_writel(pcie, PCIE_PF_DBG, val);
+
+ mobiveil_host_init(mv_pci, true);
+
+ to = 100;
+ while (!ls_pcie_g4_link_up(mv_pci) && to--)
+ usleep_range(200, 250);
+ if (to < 0) {
+ dev_err(dev, "PCIe link training timeout\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static irqreturn_t ls_pcie_g4_isr(int irq, void *dev_id)
+{
+ struct ls_pcie_g4 *pcie = (struct ls_pcie_g4 *)dev_id;
+ struct mobiveil_pcie *mv_pci = &pcie->pci;
+ u32 val;
+
+ val = mobiveil_csr_readl(mv_pci, PAB_INTP_AMBA_MISC_STAT);
+ if (!val)
+ return IRQ_NONE;
+
+ if (val & PAB_INTP_RESET) {
+ ls_pcie_g4_disable_interrupt(pcie);
+ schedule_delayed_work(&pcie->dwork, msecs_to_jiffies(1));
+ }
+
+ mobiveil_csr_writel(mv_pci, val, PAB_INTP_AMBA_MISC_STAT);
+
+ return IRQ_HANDLED;
+}
+
+static int ls_pcie_g4_interrupt_init(struct mobiveil_pcie *mv_pci)
+{
+ struct ls_pcie_g4 *pcie = to_ls_pcie_g4(mv_pci);
+ struct platform_device *pdev = mv_pci->pdev;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ pcie->irq = platform_get_irq_byname(pdev, "intr");
+ if (pcie->irq < 0) {
+ dev_err(dev, "Can't get 'intr' IRQ, errno = %d\n", pcie->irq);
+ return pcie->irq;
+ }
+ ret = devm_request_irq(dev, pcie->irq, ls_pcie_g4_isr,
+ IRQF_SHARED, pdev->name, pcie);
+ if (ret) {
+ dev_err(dev, "Can't register PCIe IRQ, errno = %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ls_pcie_g4_reset(struct work_struct *work)
+{
+ struct delayed_work *dwork = container_of(work, struct delayed_work,
+ work);
+ struct ls_pcie_g4 *pcie = container_of(dwork, struct ls_pcie_g4, dwork);
+ struct mobiveil_pcie *mv_pci = &pcie->pci;
+ u16 ctrl;
+
+ ctrl = mobiveil_csr_readw(mv_pci, PCI_BRIDGE_CONTROL);
+ ctrl &= ~PCI_BRIDGE_CTL_BUS_RESET;
+ mobiveil_csr_writew(mv_pci, ctrl, PCI_BRIDGE_CONTROL);
+
+ if (!ls_pcie_g4_reinit_hw(pcie))
+ return;
+
+ ls_pcie_g4_enable_interrupt(pcie);
+}
+
+static struct mobiveil_rp_ops ls_pcie_g4_rp_ops = {
+ .interrupt_init = ls_pcie_g4_interrupt_init,
+};
+
+static const struct mobiveil_pab_ops ls_pcie_g4_pab_ops = {
+ .link_up = ls_pcie_g4_link_up,
+};
+
+static int __init ls_pcie_g4_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pci_host_bridge *bridge;
+ struct mobiveil_pcie *mv_pci;
+ struct ls_pcie_g4 *pcie;
+ struct device_node *np = dev->of_node;
+ int ret;
+
+ if (!of_parse_phandle(np, "msi-parent", 0)) {
+ dev_err(dev, "Failed to find msi-parent\n");
+ return -EINVAL;
+ }
+
+ bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
+ if (!bridge)
+ return -ENOMEM;
+
+ pcie = pci_host_bridge_priv(bridge);
+ mv_pci = &pcie->pci;
+
+ mv_pci->pdev = pdev;
+ mv_pci->ops = &ls_pcie_g4_pab_ops;
+ mv_pci->rp.ops = &ls_pcie_g4_rp_ops;
+ mv_pci->rp.bridge = bridge;
+
+ platform_set_drvdata(pdev, pcie);
+
+ INIT_DELAYED_WORK(&pcie->dwork, ls_pcie_g4_reset);
+
+ ret = mobiveil_pcie_host_probe(mv_pci);
+ if (ret) {
+ dev_err(dev, "Fail to probe\n");
+ return ret;
+ }
+
+ ls_pcie_g4_enable_interrupt(pcie);
+
+ return 0;
+}
+
+static const struct of_device_id ls_pcie_g4_of_match[] = {
+ { .compatible = "fsl,lx2160a-pcie", },
+ { },
+};
+
+static struct platform_driver ls_pcie_g4_driver = {
+ .driver = {
+ .name = "layerscape-pcie-gen4",
+ .of_match_table = ls_pcie_g4_of_match,
+ .suppress_bind_attrs = true,
+ },
+};
+
+builtin_platform_driver_probe(ls_pcie_g4_driver, ls_pcie_g4_probe);
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