diff options
Diffstat (limited to 'drivers/pci/controller/mobiveil/pcie-mobiveil-host.c')
| -rw-r--r-- | drivers/pci/controller/mobiveil/pcie-mobiveil-host.c | 593 |
1 files changed, 593 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..31a7bdebe --- /dev/null +++ b/drivers/pci/controller/mobiveil/pcie-mobiveil-host.c @@ -0,0 +1,593 @@ +// 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, 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) { + int ret; + ret = generic_handle_domain_irq(rp->intx_domain, + bit + 1); + if (ret) + 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); + + generic_handle_domain_irq(msi->dev_domain, msi_data); + + 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_NORMAL << 8; + mobiveil_csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS); + + return 0; +} + +static void mobiveil_mask_intx_irq(struct irq_data *data) +{ + struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data); + struct mobiveil_root_port *rp; + unsigned long flags; + u32 mask, shifted_val; + + 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 mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data); + struct mobiveil_root_port *rp; + unsigned long flags; + u32 shifted_val, mask; + + 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); +} |