1 files changed, 600 insertions, 0 deletions

diff --git a/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c b/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c
new file mode 100644
index 000000000..a2632d02c
--- /dev/null
+++ b/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c
@@ -0,0 +1,600 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCIe host controller driver for Mobiveil PCIe Host controller
+ *
+ * Copyright (c) 2018 Mobiveil Inc.
+ * Copyright 2019-2020 NXP
+ *
+ * Author: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
+ *	   Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/of_pci.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "pcie-mobiveil.h"
+
+static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
+{
+	/* Only one device down on each root port */
+	if (pci_is_root_bus(bus) && (devfn > 0))
+		return false;
+
+	/*
+	 * Do not read more than one device on the bus directly
+	 * attached to RC
+	 */
+	if ((bus->primary == to_pci_host_bridge(bus->bridge)->busnr) && (PCI_SLOT(devfn) > 0))
+		return false;
+
+	return true;
+}
+
+/*
+ * mobiveil_pcie_map_bus - routine to get the configuration base of either
+ * root port or endpoint
+ */
+static void __iomem *mobiveil_pcie_map_bus(struct pci_bus *bus,
+					   unsigned int devfn, int where)
+{
+	struct mobiveil_pcie *pcie = bus->sysdata;
+	struct mobiveil_root_port *rp = &pcie->rp;
+	u32 value;
+
+	if (!mobiveil_pcie_valid_device(bus, devfn))
+		return NULL;
+
+	/* RC config access */
+	if (pci_is_root_bus(bus))
+		return pcie->csr_axi_slave_base + where;
+
+	/*
+	 * EP config access (in Config/APIO space)
+	 * Program PEX Address base (31..16 bits) with appropriate value
+	 * (BDF) in PAB_AXI_AMAP_PEX_WIN_L0 Register.
+	 * Relies on pci_lock serialization
+	 */
+	value = bus->number << PAB_BUS_SHIFT |
+		PCI_SLOT(devfn) << PAB_DEVICE_SHIFT |
+		PCI_FUNC(devfn) << PAB_FUNCTION_SHIFT;
+
+	mobiveil_csr_writel(pcie, value, PAB_AXI_AMAP_PEX_WIN_L(WIN_NUM_0));
+
+	return rp->config_axi_slave_base + where;
+}
+
+static struct pci_ops mobiveil_pcie_ops = {
+	.map_bus = mobiveil_pcie_map_bus,
+	.read = pci_generic_config_read,
+	.write = pci_generic_config_write,
+};
+
+static void mobiveil_pcie_isr(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct mobiveil_pcie *pcie = irq_desc_get_handler_data(desc);
+	struct device *dev = &pcie->pdev->dev;
+	struct mobiveil_root_port *rp = &pcie->rp;
+	struct mobiveil_msi *msi = &rp->msi;
+	u32 msi_data, msi_addr_lo, msi_addr_hi;
+	u32 intr_status, msi_status;
+	unsigned long shifted_status;
+	u32 bit, virq, val, mask;
+
+	/*
+	 * The core provides a single interrupt for both INTx/MSI messages.
+	 * So we'll read both INTx and MSI status
+	 */
+
+	chained_irq_enter(chip, desc);
+
+	/* read INTx status */
+	val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
+	mask = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
+	intr_status = val & mask;
+
+	/* Handle INTx */
+	if (intr_status & PAB_INTP_INTX_MASK) {
+		shifted_status = mobiveil_csr_readl(pcie,
+						    PAB_INTP_AMBA_MISC_STAT);
+		shifted_status &= PAB_INTP_INTX_MASK;
+		shifted_status >>= PAB_INTX_START;
+		do {
+			for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
+				virq = irq_find_mapping(rp->intx_domain,
+							bit + 1);
+				if (virq)
+					generic_handle_irq(virq);
+				else
+					dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
+							    bit);
+
+				/* clear interrupt handled */
+				mobiveil_csr_writel(pcie,
+						    1 << (PAB_INTX_START + bit),
+						    PAB_INTP_AMBA_MISC_STAT);
+			}
+
+			shifted_status = mobiveil_csr_readl(pcie,
+							    PAB_INTP_AMBA_MISC_STAT);
+			shifted_status &= PAB_INTP_INTX_MASK;
+			shifted_status >>= PAB_INTX_START;
+		} while (shifted_status != 0);
+	}
+
+	/* read extra MSI status register */
+	msi_status = readl_relaxed(pcie->apb_csr_base + MSI_STATUS_OFFSET);
+
+	/* handle MSI interrupts */
+	while (msi_status & 1) {
+		msi_data = readl_relaxed(pcie->apb_csr_base + MSI_DATA_OFFSET);
+
+		/*
+		 * MSI_STATUS_OFFSET register gets updated to zero
+		 * once we pop not only the MSI data but also address
+		 * from MSI hardware FIFO. So keeping these following
+		 * two dummy reads.
+		 */
+		msi_addr_lo = readl_relaxed(pcie->apb_csr_base +
+					    MSI_ADDR_L_OFFSET);
+		msi_addr_hi = readl_relaxed(pcie->apb_csr_base +
+					    MSI_ADDR_H_OFFSET);
+		dev_dbg(dev, "MSI registers, data: %08x, addr: %08x:%08x\n",
+			msi_data, msi_addr_hi, msi_addr_lo);
+
+		virq = irq_find_mapping(msi->dev_domain, msi_data);
+		if (virq)
+			generic_handle_irq(virq);
+
+		msi_status = readl_relaxed(pcie->apb_csr_base +
+					   MSI_STATUS_OFFSET);
+	}
+
+	/* Clear the interrupt status */
+	mobiveil_csr_writel(pcie, intr_status, PAB_INTP_AMBA_MISC_STAT);
+	chained_irq_exit(chip, desc);
+}
+
+static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie)
+{
+	struct device *dev = &pcie->pdev->dev;
+	struct platform_device *pdev = pcie->pdev;
+	struct device_node *node = dev->of_node;
+	struct mobiveil_root_port *rp = &pcie->rp;
+	struct resource *res;
+
+	/* map config resource */
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+					   "config_axi_slave");
+	rp->config_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
+	if (IS_ERR(rp->config_axi_slave_base))
+		return PTR_ERR(rp->config_axi_slave_base);
+	rp->ob_io_res = res;
+
+	/* map csr resource */
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+					   "csr_axi_slave");
+	pcie->csr_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
+	if (IS_ERR(pcie->csr_axi_slave_base))
+		return PTR_ERR(pcie->csr_axi_slave_base);
+	pcie->pcie_reg_base = res->start;
+
+	/* read the number of windows requested */
+	if (of_property_read_u32(node, "apio-wins", &pcie->apio_wins))
+		pcie->apio_wins = MAX_PIO_WINDOWS;
+
+	if (of_property_read_u32(node, "ppio-wins", &pcie->ppio_wins))
+		pcie->ppio_wins = MAX_PIO_WINDOWS;
+
+	return 0;
+}
+
+static void mobiveil_pcie_enable_msi(struct mobiveil_pcie *pcie)
+{
+	phys_addr_t msg_addr = pcie->pcie_reg_base;
+	struct mobiveil_msi *msi = &pcie->rp.msi;
+
+	msi->num_of_vectors = PCI_NUM_MSI;
+	msi->msi_pages_phys = (phys_addr_t)msg_addr;
+
+	writel_relaxed(lower_32_bits(msg_addr),
+		       pcie->apb_csr_base + MSI_BASE_LO_OFFSET);
+	writel_relaxed(upper_32_bits(msg_addr),
+		       pcie->apb_csr_base + MSI_BASE_HI_OFFSET);
+	writel_relaxed(4096, pcie->apb_csr_base + MSI_SIZE_OFFSET);
+	writel_relaxed(1, pcie->apb_csr_base + MSI_ENABLE_OFFSET);
+}
+
+int mobiveil_host_init(struct mobiveil_pcie *pcie, bool reinit)
+{
+	struct mobiveil_root_port *rp = &pcie->rp;
+	struct pci_host_bridge *bridge = rp->bridge;
+	u32 value, pab_ctrl, type;
+	struct resource_entry *win;
+
+	pcie->ib_wins_configured = 0;
+	pcie->ob_wins_configured = 0;
+
+	if (!reinit) {
+		/* setup bus numbers */
+		value = mobiveil_csr_readl(pcie, PCI_PRIMARY_BUS);
+		value &= 0xff000000;
+		value |= 0x00ff0100;
+		mobiveil_csr_writel(pcie, value, PCI_PRIMARY_BUS);
+	}
+
+	/*
+	 * program Bus Master Enable Bit in Command Register in PAB Config
+	 * Space
+	 */
+	value = mobiveil_csr_readl(pcie, PCI_COMMAND);
+	value |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
+	mobiveil_csr_writel(pcie, value, PCI_COMMAND);
+
+	/*
+	 * program PIO Enable Bit to 1 (and PEX PIO Enable to 1) in PAB_CTRL
+	 * register
+	 */
+	pab_ctrl = mobiveil_csr_readl(pcie, PAB_CTRL);
+	pab_ctrl |= (1 << AMBA_PIO_ENABLE_SHIFT) | (1 << PEX_PIO_ENABLE_SHIFT);
+	mobiveil_csr_writel(pcie, pab_ctrl, PAB_CTRL);
+
+	/*
+	 * program PIO Enable Bit to 1 and Config Window Enable Bit to 1 in
+	 * PAB_AXI_PIO_CTRL Register
+	 */
+	value = mobiveil_csr_readl(pcie, PAB_AXI_PIO_CTRL);
+	value |= APIO_EN_MASK;
+	mobiveil_csr_writel(pcie, value, PAB_AXI_PIO_CTRL);
+
+	/* Enable PCIe PIO master */
+	value = mobiveil_csr_readl(pcie, PAB_PEX_PIO_CTRL);
+	value |= 1 << PIO_ENABLE_SHIFT;
+	mobiveil_csr_writel(pcie, value, PAB_PEX_PIO_CTRL);
+
+	/*
+	 * we'll program one outbound window for config reads and
+	 * another default inbound window for all the upstream traffic
+	 * rest of the outbound windows will be configured according to
+	 * the "ranges" field defined in device tree
+	 */
+
+	/* config outbound translation window */
+	program_ob_windows(pcie, WIN_NUM_0, rp->ob_io_res->start, 0,
+			   CFG_WINDOW_TYPE, resource_size(rp->ob_io_res));
+
+	/* memory inbound translation window */
+	program_ib_windows(pcie, WIN_NUM_0, 0, 0, MEM_WINDOW_TYPE, IB_WIN_SIZE);
+
+	/* Get the I/O and memory ranges from DT */
+	resource_list_for_each_entry(win, &bridge->windows) {
+		if (resource_type(win->res) == IORESOURCE_MEM)
+			type = MEM_WINDOW_TYPE;
+		else if (resource_type(win->res) == IORESOURCE_IO)
+			type = IO_WINDOW_TYPE;
+		else
+			continue;
+
+		/* configure outbound translation window */
+		program_ob_windows(pcie, pcie->ob_wins_configured,
+				   win->res->start,
+				   win->res->start - win->offset,
+				   type, resource_size(win->res));
+	}
+
+	/* fixup for PCIe class register */
+	value = mobiveil_csr_readl(pcie, PAB_INTP_AXI_PIO_CLASS);
+	value &= 0xff;
+	value |= (PCI_CLASS_BRIDGE_PCI << 16);
+	mobiveil_csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS);
+
+	return 0;
+}
+
+static void mobiveil_mask_intx_irq(struct irq_data *data)
+{
+	struct irq_desc *desc = irq_to_desc(data->irq);
+	struct mobiveil_pcie *pcie;
+	struct mobiveil_root_port *rp;
+	unsigned long flags;
+	u32 mask, shifted_val;
+
+	pcie = irq_desc_get_chip_data(desc);
+	rp = &pcie->rp;
+	mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
+	raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
+	shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
+	shifted_val &= ~mask;
+	mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
+	raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
+}
+
+static void mobiveil_unmask_intx_irq(struct irq_data *data)
+{
+	struct irq_desc *desc = irq_to_desc(data->irq);
+	struct mobiveil_pcie *pcie;
+	struct mobiveil_root_port *rp;
+	unsigned long flags;
+	u32 shifted_val, mask;
+
+	pcie = irq_desc_get_chip_data(desc);
+	rp = &pcie->rp;
+	mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
+	raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
+	shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
+	shifted_val |= mask;
+	mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
+	raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
+}
+
+static struct irq_chip intx_irq_chip = {
+	.name = "mobiveil_pcie:intx",
+	.irq_enable = mobiveil_unmask_intx_irq,
+	.irq_disable = mobiveil_mask_intx_irq,
+	.irq_mask = mobiveil_mask_intx_irq,
+	.irq_unmask = mobiveil_unmask_intx_irq,
+};
+
+/* routine to setup the INTx related data */
+static int mobiveil_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
+				  irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &intx_irq_chip, handle_level_irq);
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+/* INTx domain operations structure */
+static const struct irq_domain_ops intx_domain_ops = {
+	.map = mobiveil_pcie_intx_map,
+};
+
+static struct irq_chip mobiveil_msi_irq_chip = {
+	.name = "Mobiveil PCIe MSI",
+	.irq_mask = pci_msi_mask_irq,
+	.irq_unmask = pci_msi_unmask_irq,
+};
+
+static struct msi_domain_info mobiveil_msi_domain_info = {
+	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+		   MSI_FLAG_PCI_MSIX),
+	.chip	= &mobiveil_msi_irq_chip,
+};
+
+static void mobiveil_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+	struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
+	phys_addr_t addr = pcie->pcie_reg_base + (data->hwirq * sizeof(int));
+
+	msg->address_lo = lower_32_bits(addr);
+	msg->address_hi = upper_32_bits(addr);
+	msg->data = data->hwirq;
+
+	dev_dbg(&pcie->pdev->dev, "msi#%d address_hi %#x address_lo %#x\n",
+		(int)data->hwirq, msg->address_hi, msg->address_lo);
+}
+
+static int mobiveil_msi_set_affinity(struct irq_data *irq_data,
+				     const struct cpumask *mask, bool force)
+{
+	return -EINVAL;
+}
+
+static struct irq_chip mobiveil_msi_bottom_irq_chip = {
+	.name			= "Mobiveil MSI",
+	.irq_compose_msi_msg	= mobiveil_compose_msi_msg,
+	.irq_set_affinity	= mobiveil_msi_set_affinity,
+};
+
+static int mobiveil_irq_msi_domain_alloc(struct irq_domain *domain,
+					 unsigned int virq,
+					 unsigned int nr_irqs, void *args)
+{
+	struct mobiveil_pcie *pcie = domain->host_data;
+	struct mobiveil_msi *msi = &pcie->rp.msi;
+	unsigned long bit;
+
+	WARN_ON(nr_irqs != 1);
+	mutex_lock(&msi->lock);
+
+	bit = find_first_zero_bit(msi->msi_irq_in_use, msi->num_of_vectors);
+	if (bit >= msi->num_of_vectors) {
+		mutex_unlock(&msi->lock);
+		return -ENOSPC;
+	}
+
+	set_bit(bit, msi->msi_irq_in_use);
+
+	mutex_unlock(&msi->lock);
+
+	irq_domain_set_info(domain, virq, bit, &mobiveil_msi_bottom_irq_chip,
+			    domain->host_data, handle_level_irq, NULL, NULL);
+	return 0;
+}
+
+static void mobiveil_irq_msi_domain_free(struct irq_domain *domain,
+					 unsigned int virq,
+					 unsigned int nr_irqs)
+{
+	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+	struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(d);
+	struct mobiveil_msi *msi = &pcie->rp.msi;
+
+	mutex_lock(&msi->lock);
+
+	if (!test_bit(d->hwirq, msi->msi_irq_in_use))
+		dev_err(&pcie->pdev->dev, "trying to free unused MSI#%lu\n",
+			d->hwirq);
+	else
+		__clear_bit(d->hwirq, msi->msi_irq_in_use);
+
+	mutex_unlock(&msi->lock);
+}
+static const struct irq_domain_ops msi_domain_ops = {
+	.alloc	= mobiveil_irq_msi_domain_alloc,
+	.free	= mobiveil_irq_msi_domain_free,
+};
+
+static int mobiveil_allocate_msi_domains(struct mobiveil_pcie *pcie)
+{
+	struct device *dev = &pcie->pdev->dev;
+	struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
+	struct mobiveil_msi *msi = &pcie->rp.msi;
+
+	mutex_init(&msi->lock);
+	msi->dev_domain = irq_domain_add_linear(NULL, msi->num_of_vectors,
+						&msi_domain_ops, pcie);
+	if (!msi->dev_domain) {
+		dev_err(dev, "failed to create IRQ domain\n");
+		return -ENOMEM;
+	}
+
+	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
+						    &mobiveil_msi_domain_info,
+						    msi->dev_domain);
+	if (!msi->msi_domain) {
+		dev_err(dev, "failed to create MSI domain\n");
+		irq_domain_remove(msi->dev_domain);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int mobiveil_pcie_init_irq_domain(struct mobiveil_pcie *pcie)
+{
+	struct device *dev = &pcie->pdev->dev;
+	struct device_node *node = dev->of_node;
+	struct mobiveil_root_port *rp = &pcie->rp;
+
+	/* setup INTx */
+	rp->intx_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
+						&intx_domain_ops, pcie);
+
+	if (!rp->intx_domain) {
+		dev_err(dev, "Failed to get a INTx IRQ domain\n");
+		return -ENOMEM;
+	}
+
+	raw_spin_lock_init(&rp->intx_mask_lock);
+
+	/* setup MSI */
+	return mobiveil_allocate_msi_domains(pcie);
+}
+
+static int mobiveil_pcie_integrated_interrupt_init(struct mobiveil_pcie *pcie)
+{
+	struct platform_device *pdev = pcie->pdev;
+	struct device *dev = &pdev->dev;
+	struct mobiveil_root_port *rp = &pcie->rp;
+	struct resource *res;
+	int ret;
+
+	/* map MSI config resource */
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "apb_csr");
+	pcie->apb_csr_base = devm_pci_remap_cfg_resource(dev, res);
+	if (IS_ERR(pcie->apb_csr_base))
+		return PTR_ERR(pcie->apb_csr_base);
+
+	/* setup MSI hardware registers */
+	mobiveil_pcie_enable_msi(pcie);
+
+	rp->irq = platform_get_irq(pdev, 0);
+	if (rp->irq < 0)
+		return rp->irq;
+
+	/* initialize the IRQ domains */
+	ret = mobiveil_pcie_init_irq_domain(pcie);
+	if (ret) {
+		dev_err(dev, "Failed creating IRQ Domain\n");
+		return ret;
+	}
+
+	irq_set_chained_handler_and_data(rp->irq, mobiveil_pcie_isr, pcie);
+
+	/* Enable interrupts */
+	mobiveil_csr_writel(pcie, (PAB_INTP_INTX_MASK | PAB_INTP_MSI_MASK),
+			    PAB_INTP_AMBA_MISC_ENB);
+
+
+	return 0;
+}
+
+static int mobiveil_pcie_interrupt_init(struct mobiveil_pcie *pcie)
+{
+	struct mobiveil_root_port *rp = &pcie->rp;
+
+	if (rp->ops->interrupt_init)
+		return rp->ops->interrupt_init(pcie);
+
+	return mobiveil_pcie_integrated_interrupt_init(pcie);
+}
+
+static bool mobiveil_pcie_is_bridge(struct mobiveil_pcie *pcie)
+{
+	u32 header_type;
+
+	header_type = mobiveil_csr_readb(pcie, PCI_HEADER_TYPE);
+	header_type &= 0x7f;
+
+	return header_type == PCI_HEADER_TYPE_BRIDGE;
+}
+
+int mobiveil_pcie_host_probe(struct mobiveil_pcie *pcie)
+{
+	struct mobiveil_root_port *rp = &pcie->rp;
+	struct pci_host_bridge *bridge = rp->bridge;
+	struct device *dev = &pcie->pdev->dev;
+	int ret;
+
+	ret = mobiveil_pcie_parse_dt(pcie);
+	if (ret) {
+		dev_err(dev, "Parsing DT failed, ret: %x\n", ret);
+		return ret;
+	}
+
+	if (!mobiveil_pcie_is_bridge(pcie))
+		return -ENODEV;
+
+	/*
+	 * configure all inbound and outbound windows and prepare the RC for
+	 * config access
+	 */
+	ret = mobiveil_host_init(pcie, false);
+	if (ret) {
+		dev_err(dev, "Failed to initialize host\n");
+		return ret;
+	}
+
+	ret = mobiveil_pcie_interrupt_init(pcie);
+	if (ret) {
+		dev_err(dev, "Interrupt init failed\n");
+		return ret;
+	}
+
+	/* Initialize bridge */
+	bridge->sysdata = pcie;
+	bridge->ops = &mobiveil_pcie_ops;
+
+	ret = mobiveil_bringup_link(pcie);
+	if (ret) {
+		dev_info(dev, "link bring-up failed\n");
+		return ret;
+	}
+
+	return pci_host_probe(bridge);
+}