irq-armada-370-xp.c
/*
* Marvell Armada 370 and Armada XP SoC IRQ handling
*
* Copyright (C) 2012 Marvell
*
* Lior Amsalem <alior@marvell.com>
* Gregory CLEMENT <gregory.clement@free-electrons.com>
* Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
* Ben Dooks <ben.dooks@codethink.co.uk>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/cpu.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/irqdomain.h>
#include <linux/slab.h>
#include <linux/syscore_ops.h>
#include <linux/msi.h>
#include <asm/mach/arch.h>
#include <asm/exception.h>
#include <asm/smp_plat.h>
#include <asm/mach/irq.h>
/* Interrupt Controller Registers Map */
#define ARMADA_370_XP_INT_SET_MASK_OFFS (0x48)
#define ARMADA_370_XP_INT_CLEAR_MASK_OFFS (0x4C)
#define ARMADA_370_XP_INT_FABRIC_MASK_OFFS (0x54)
#define ARMADA_370_XP_INT_CAUSE_PERF(cpu) (1 << cpu)
#define ARMADA_370_XP_INT_CONTROL (0x00)
#define ARMADA_370_XP_INT_SET_ENABLE_OFFS (0x30)
#define ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS (0x34)
#define ARMADA_370_XP_INT_SOURCE_CTL(irq) (0x100 + irq*4)
#define ARMADA_370_XP_INT_SOURCE_CPU_MASK 0xF
#define ARMADA_370_XP_INT_IRQ_FIQ_MASK(cpuid) ((BIT(0) | BIT(8)) << cpuid)
#define ARMADA_370_XP_CPU_INTACK_OFFS (0x44)
#define ARMADA_375_PPI_CAUSE (0x10)
#define ARMADA_370_XP_SW_TRIG_INT_OFFS (0x4)
#define ARMADA_370_XP_IN_DRBEL_MSK_OFFS (0xc)
#define ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS (0x8)
#define ARMADA_370_XP_MAX_PER_CPU_IRQS (28)
#define IPI_DOORBELL_START (0)
#define IPI_DOORBELL_END (8)
#define IPI_DOORBELL_MASK 0xFF
#define PCI_MSI_DOORBELL_START (16)
#define PCI_MSI_DOORBELL_NR (16)
#define PCI_MSI_DOORBELL_END (32)
#define PCI_MSI_DOORBELL_MASK 0xFFFF0000
static void __iomem *per_cpu_int_base;
static void __iomem *main_int_base;
static struct irq_domain *armada_370_xp_mpic_domain;
static u32 doorbell_mask_reg;
static int parent_irq;
#ifdef CONFIG_PCI_MSI
static struct irq_domain *armada_370_xp_msi_domain;
static DECLARE_BITMAP(msi_used, PCI_MSI_DOORBELL_NR);
static DEFINE_MUTEX(msi_used_lock);
static phys_addr_t msi_doorbell_addr;
#endif
static inline bool is_percpu_irq(irq_hw_number_t irq)
{
if (irq <= ARMADA_370_XP_MAX_PER_CPU_IRQS)
return true;
return false;
}
/*
* In SMP mode:
* For shared global interrupts, mask/unmask global enable bit
* For CPU interrupts, mask/unmask the calling CPU's bit
*/
static void armada_370_xp_irq_mask(struct irq_data *d)
{
irq_hw_number_t hwirq = irqd_to_hwirq(d);
if (!is_percpu_irq(hwirq))
writel(hwirq, main_int_base +
ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
else
writel(hwirq, per_cpu_int_base +
ARMADA_370_XP_INT_SET_MASK_OFFS);
}
static void armada_370_xp_irq_unmask(struct irq_data *d)
{
irq_hw_number_t hwirq = irqd_to_hwirq(d);
if (!is_percpu_irq(hwirq))
writel(hwirq, main_int_base +
ARMADA_370_XP_INT_SET_ENABLE_OFFS);
else
writel(hwirq, per_cpu_int_base +
ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
}
#ifdef CONFIG_PCI_MSI
static int armada_370_xp_alloc_msi(void)
{
int hwirq;
mutex_lock(&msi_used_lock);
hwirq = find_first_zero_bit(&msi_used, PCI_MSI_DOORBELL_NR);
if (hwirq >= PCI_MSI_DOORBELL_NR)
hwirq = -ENOSPC;
else
set_bit(hwirq, msi_used);
mutex_unlock(&msi_used_lock);
return hwirq;
}
static void armada_370_xp_free_msi(int hwirq)
{
mutex_lock(&msi_used_lock);
if (!test_bit(hwirq, msi_used))
pr_err("trying to free unused MSI#%d\n", hwirq);
else
clear_bit(hwirq, msi_used);
mutex_unlock(&msi_used_lock);
}
static int armada_370_xp_setup_msi_irq(struct msi_controller *chip,
struct pci_dev *pdev,
struct msi_desc *desc)
{
struct msi_msg msg;
int virq, hwirq;
/* We support MSI, but not MSI-X */
if (desc->msi_attrib.is_msix)
return -EINVAL;
hwirq = armada_370_xp_alloc_msi();
if (hwirq < 0)
return hwirq;
virq = irq_create_mapping(armada_370_xp_msi_domain, hwirq);
if (!virq) {
armada_370_xp_free_msi(hwirq);
return -EINVAL;
}
irq_set_msi_desc(virq, desc);
msg.address_lo = msi_doorbell_addr;
msg.address_hi = 0;
msg.data = 0xf00 | (hwirq + 16);
pci_write_msi_msg(virq, &msg);
return 0;
}
static void armada_370_xp_teardown_msi_irq(struct msi_controller *chip,
unsigned int irq)
{
struct irq_data *d = irq_get_irq_data(irq);
unsigned long hwirq = d->hwirq;
irq_dispose_mapping(irq);
armada_370_xp_free_msi(hwirq);
}
static struct irq_chip armada_370_xp_msi_irq_chip = {
.name = "armada_370_xp_msi_irq",
.irq_enable = pci_msi_unmask_irq,
.irq_disable = pci_msi_mask_irq,
.irq_mask = pci_msi_mask_irq,
.irq_unmask = pci_msi_unmask_irq,
};
static int armada_370_xp_msi_map(struct irq_domain *domain, unsigned int virq,
irq_hw_number_t hw)
{
irq_set_chip_and_handler(virq, &armada_370_xp_msi_irq_chip,
handle_simple_irq);
return 0;
}
static const struct irq_domain_ops armada_370_xp_msi_irq_ops = {
.map = armada_370_xp_msi_map,
};
static int armada_370_xp_msi_init(struct device_node *node,
phys_addr_t main_int_phys_base)
{
struct msi_controller *msi_chip;
u32 reg;
int ret;
msi_doorbell_addr = main_int_phys_base +
ARMADA_370_XP_SW_TRIG_INT_OFFS;
msi_chip = kzalloc(sizeof(*msi_chip), GFP_KERNEL);
if (!msi_chip)
return -ENOMEM;
msi_chip->setup_irq = armada_370_xp_setup_msi_irq;
msi_chip->teardown_irq = armada_370_xp_teardown_msi_irq;
msi_chip->of_node = node;
armada_370_xp_msi_domain =
irq_domain_add_linear(NULL, PCI_MSI_DOORBELL_NR,
&armada_370_xp_msi_irq_ops,
NULL);
if (!armada_370_xp_msi_domain) {
kfree(msi_chip);
return -ENOMEM;
}
ret = of_pci_msi_chip_add(msi_chip);
if (ret < 0) {
irq_domain_remove(armada_370_xp_msi_domain);
kfree(msi_chip);
return ret;
}
reg = readl(per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS)
| PCI_MSI_DOORBELL_MASK;
writel(reg, per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
/* Unmask IPI interrupt */
writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
return 0;
}
#else
static inline int armada_370_xp_msi_init(struct device_node *node,
phys_addr_t main_int_phys_base)
{
return 0;
}
#endif
#ifdef CONFIG_SMP
static DEFINE_RAW_SPINLOCK(irq_controller_lock);
static int armada_xp_set_affinity(struct irq_data *d,
const struct cpumask *mask_val, bool force)
{
irq_hw_number_t hwirq = irqd_to_hwirq(d);
unsigned long reg, mask;
int cpu;
/* Select a single core from the affinity mask which is online */
cpu = cpumask_any_and(mask_val, cpu_online_mask);
mask = 1UL << cpu_logical_map(cpu);
raw_spin_lock(&irq_controller_lock);
reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
reg = (reg & (~ARMADA_370_XP_INT_SOURCE_CPU_MASK)) | mask;
writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
raw_spin_unlock(&irq_controller_lock);
return IRQ_SET_MASK_OK;
}
#endif
static struct irq_chip armada_370_xp_irq_chip = {
.name = "armada_370_xp_irq",
.irq_mask = armada_370_xp_irq_mask,
.irq_mask_ack = armada_370_xp_irq_mask,
.irq_unmask = armada_370_xp_irq_unmask,
#ifdef CONFIG_SMP
.irq_set_affinity = armada_xp_set_affinity,
#endif
.flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND,
};
static int armada_370_xp_mpic_irq_map(struct irq_domain *h,
unsigned int virq, irq_hw_number_t hw)
{
armada_370_xp_irq_mask(irq_get_irq_data(virq));
if (!is_percpu_irq(hw))
writel(hw, per_cpu_int_base +
ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
else
writel(hw, main_int_base + ARMADA_370_XP_INT_SET_ENABLE_OFFS);
irq_set_status_flags(virq, IRQ_LEVEL);
if (is_percpu_irq(hw)) {
irq_set_percpu_devid(virq);
irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
handle_percpu_devid_irq);
} else {
irq_set_chip_and_handler(virq, &armada_370_xp_irq_chip,
handle_level_irq);
}
irq_set_probe(virq);
irq_clear_status_flags(virq, IRQ_NOAUTOEN);
return 0;
}
static void armada_xp_mpic_smp_cpu_init(void)
{
u32 control;
int nr_irqs, i;
control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
nr_irqs = (control >> 2) & 0x3ff;
for (i = 0; i < nr_irqs; i++)
writel(i, per_cpu_int_base + ARMADA_370_XP_INT_SET_MASK_OFFS);
/* Clear pending IPIs */
writel(0, per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
/* Enable first 8 IPIs */
writel(IPI_DOORBELL_MASK, per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
/* Unmask IPI interrupt */
writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
}
static void armada_xp_mpic_perf_init(void)
{
unsigned long cpuid = cpu_logical_map(smp_processor_id());
/* Enable Performance Counter Overflow interrupts */
writel(ARMADA_370_XP_INT_CAUSE_PERF(cpuid),
per_cpu_int_base + ARMADA_370_XP_INT_FABRIC_MASK_OFFS);
}
#ifdef CONFIG_SMP
static void armada_mpic_send_doorbell(const struct cpumask *mask,
unsigned int irq)
{
int cpu;
unsigned long map = 0;
/* Convert our logical CPU mask into a physical one. */
for_each_cpu(cpu, mask)
map |= 1 << cpu_logical_map(cpu);
/*
* Ensure that stores to Normal memory are visible to the
* other CPUs before issuing the IPI.
*/
dsb();
/* submit softirq */
writel((map << 8) | irq, main_int_base +
ARMADA_370_XP_SW_TRIG_INT_OFFS);
}
static int armada_xp_mpic_secondary_init(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
if (action == CPU_STARTING || action == CPU_STARTING_FROZEN) {
armada_xp_mpic_perf_init();
armada_xp_mpic_smp_cpu_init();
}
return NOTIFY_OK;
}
static struct notifier_block armada_370_xp_mpic_cpu_notifier = {
.notifier_call = armada_xp_mpic_secondary_init,
.priority = 100,
};
static int mpic_cascaded_secondary_init(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
if (action == CPU_STARTING || action == CPU_STARTING_FROZEN) {
armada_xp_mpic_perf_init();
enable_percpu_irq(parent_irq, IRQ_TYPE_NONE);
}
return NOTIFY_OK;
}
static struct notifier_block mpic_cascaded_cpu_notifier = {
.notifier_call = mpic_cascaded_secondary_init,
.priority = 100,
};
#endif /* CONFIG_SMP */
static const struct irq_domain_ops armada_370_xp_mpic_irq_ops = {
.map = armada_370_xp_mpic_irq_map,
.xlate = irq_domain_xlate_onecell,
};
#ifdef CONFIG_PCI_MSI
static void armada_370_xp_handle_msi_irq(struct pt_regs *regs, bool is_chained)
{
u32 msimask, msinr;
msimask = readl_relaxed(per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
& PCI_MSI_DOORBELL_MASK;
writel(~msimask, per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
for (msinr = PCI_MSI_DOORBELL_START;
msinr < PCI_MSI_DOORBELL_END; msinr++) {
int irq;
if (!(msimask & BIT(msinr)))
continue;
if (is_chained) {
irq = irq_find_mapping(armada_370_xp_msi_domain,
msinr - 16);
generic_handle_irq(irq);
} else {
irq = msinr - 16;
handle_domain_irq(armada_370_xp_msi_domain,
irq, regs);
}
}
}
#else
static void armada_370_xp_handle_msi_irq(struct pt_regs *r, bool b) {}
#endif
static void armada_370_xp_mpic_handle_cascade_irq(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned long irqmap, irqn, irqsrc, cpuid;
unsigned int cascade_irq;
chained_irq_enter(chip, desc);
irqmap = readl_relaxed(per_cpu_int_base + ARMADA_375_PPI_CAUSE);
cpuid = cpu_logical_map(smp_processor_id());
for_each_set_bit(irqn, &irqmap, BITS_PER_LONG) {
irqsrc = readl_relaxed(main_int_base +
ARMADA_370_XP_INT_SOURCE_CTL(irqn));
/* Check if the interrupt is not masked on current CPU.
* Test IRQ (0-1) and FIQ (8-9) mask bits.
*/
if (!(irqsrc & ARMADA_370_XP_INT_IRQ_FIQ_MASK(cpuid)))
continue;
if (irqn == 1) {
armada_370_xp_handle_msi_irq(NULL, true);
continue;
}
cascade_irq = irq_find_mapping(armada_370_xp_mpic_domain, irqn);
generic_handle_irq(cascade_irq);
}
chained_irq_exit(chip, desc);
}
static void __exception_irq_entry
armada_370_xp_handle_irq(struct pt_regs *regs)
{
u32 irqstat, irqnr;
do {
irqstat = readl_relaxed(per_cpu_int_base +
ARMADA_370_XP_CPU_INTACK_OFFS);
irqnr = irqstat & 0x3FF;
if (irqnr > 1022)
break;
if (irqnr > 1) {
handle_domain_irq(armada_370_xp_mpic_domain,
irqnr, regs);
continue;
}
/* MSI handling */
if (irqnr == 1)
armada_370_xp_handle_msi_irq(regs, false);
#ifdef CONFIG_SMP
/* IPI Handling */
if (irqnr == 0) {
u32 ipimask, ipinr;
ipimask = readl_relaxed(per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS)
& IPI_DOORBELL_MASK;
writel(~ipimask, per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_CAUSE_OFFS);
/* Handle all pending doorbells */
for (ipinr = IPI_DOORBELL_START;
ipinr < IPI_DOORBELL_END; ipinr++) {
if (ipimask & (0x1 << ipinr))
handle_IPI(ipinr, regs);
}
continue;
}
#endif
} while (1);
}
static int armada_370_xp_mpic_suspend(void)
{
doorbell_mask_reg = readl(per_cpu_int_base +
ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
return 0;
}
static void armada_370_xp_mpic_resume(void)
{
int nirqs;
irq_hw_number_t irq;
/* Re-enable interrupts */
nirqs = (readl(main_int_base + ARMADA_370_XP_INT_CONTROL) >> 2) & 0x3ff;
for (irq = 0; irq < nirqs; irq++) {
struct irq_data *data;
int virq;
virq = irq_linear_revmap(armada_370_xp_mpic_domain, irq);
if (virq == 0)
continue;
if (!is_percpu_irq(irq))
writel(irq, per_cpu_int_base +
ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
else
writel(irq, main_int_base +
ARMADA_370_XP_INT_SET_ENABLE_OFFS);
data = irq_get_irq_data(virq);
if (!irqd_irq_disabled(data))
armada_370_xp_irq_unmask(data);
}
/* Reconfigure doorbells for IPIs and MSIs */
writel(doorbell_mask_reg,
per_cpu_int_base + ARMADA_370_XP_IN_DRBEL_MSK_OFFS);
if (doorbell_mask_reg & IPI_DOORBELL_MASK)
writel(0, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
if (doorbell_mask_reg & PCI_MSI_DOORBELL_MASK)
writel(1, per_cpu_int_base + ARMADA_370_XP_INT_CLEAR_MASK_OFFS);
}
struct syscore_ops armada_370_xp_mpic_syscore_ops = {
.suspend = armada_370_xp_mpic_suspend,
.resume = armada_370_xp_mpic_resume,
};
static int __init armada_370_xp_mpic_of_init(struct device_node *node,
struct device_node *parent)
{
struct resource main_int_res, per_cpu_int_res;
int nr_irqs, i;
u32 control;
BUG_ON(of_address_to_resource(node, 0, &main_int_res));
BUG_ON(of_address_to_resource(node, 1, &per_cpu_int_res));
BUG_ON(!request_mem_region(main_int_res.start,
resource_size(&main_int_res),
node->full_name));
BUG_ON(!request_mem_region(per_cpu_int_res.start,
resource_size(&per_cpu_int_res),
node->full_name));
main_int_base = ioremap(main_int_res.start,
resource_size(&main_int_res));
BUG_ON(!main_int_base);
per_cpu_int_base = ioremap(per_cpu_int_res.start,
resource_size(&per_cpu_int_res));
BUG_ON(!per_cpu_int_base);
control = readl(main_int_base + ARMADA_370_XP_INT_CONTROL);
nr_irqs = (control >> 2) & 0x3ff;
for (i = 0; i < nr_irqs; i++)
writel(i, main_int_base + ARMADA_370_XP_INT_CLEAR_ENABLE_OFFS);
armada_370_xp_mpic_domain =
irq_domain_add_linear(node, nr_irqs,
&armada_370_xp_mpic_irq_ops, NULL);
BUG_ON(!armada_370_xp_mpic_domain);
/* Setup for the boot CPU */
armada_xp_mpic_perf_init();
armada_xp_mpic_smp_cpu_init();
armada_370_xp_msi_init(node, main_int_res.start);
parent_irq = irq_of_parse_and_map(node, 0);
if (parent_irq <= 0) {
irq_set_default_host(armada_370_xp_mpic_domain);
set_handle_irq(armada_370_xp_handle_irq);
#ifdef CONFIG_SMP
set_smp_cross_call(armada_mpic_send_doorbell);
register_cpu_notifier(&armada_370_xp_mpic_cpu_notifier);
#endif
} else {
#ifdef CONFIG_SMP
register_cpu_notifier(&mpic_cascaded_cpu_notifier);
#endif
irq_set_chained_handler(parent_irq,
armada_370_xp_mpic_handle_cascade_irq);
}
register_syscore_ops(&armada_370_xp_mpic_syscore_ops);
return 0;
}
IRQCHIP_DECLARE(armada_370_xp_mpic, "marvell,mpic", armada_370_xp_mpic_of_init);