blob: 3adec419a45b1e18cafa7c2517d4728d36d595c4 [file] [log] [blame]
// 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;
int ret;
/* 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 */
ret = mobiveil_allocate_msi_domains(pcie);
if (ret)
return ret;
return 0;
}
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);
}