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freescale-linux-fslc/drivers/irqchip/irq-armada-370-xp.c
Ezequiel Garcia bc69b8adfe irqchip: armada-370-xp: Setup a chained handler for the MPIC 
The new Armada 375 and Armada 38x Marvell SoCs are based on Cortex-A9
CPU cores and use the ARM GIC as their main interrupt controller.
However, for various purposes (wake-up from suspend, MSI interrupts),
they have kept a separate MPIC interrupt controller, acting as a slave
to the GIC. This MPIC was already used as the primary controller on
previous Marvell SoCs, so this commit extends the existing driver to
allow the MPIC to be used as a GIC slave.

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-02-22 06:12:29 +00:00

523 lines
13 KiB
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Raw Blame History

/*
* 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/chained_irq.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/msi.h>
#include <asm/mach/arch.h>
#include <asm/exception.h>
#include <asm/smp_plat.h>
#include <asm/mach/irq.h>
#include "irqchip.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_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_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 ARMADA_370_XP_TIMER0_PER_CPU_IRQ (5)
#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;
#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
/*
* 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 (hwirq != ARMADA_370_XP_TIMER0_PER_CPU_IRQ)
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 (hwirq != ARMADA_370_XP_TIMER0_PER_CPU_IRQ)
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_chip *chip,
struct pci_dev *pdev,
struct msi_desc *desc)
{
struct msi_msg msg;
irq_hw_number_t hwirq;
int virq;
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);
write_msi_msg(virq, &msg);
return 0;
}
static void armada_370_xp_teardown_msi_irq(struct msi_chip *chip,
unsigned int irq)
{
struct irq_data *d = irq_get_irq_data(irq);
irq_dispose_mapping(irq);
armada_370_xp_free_msi(d->hwirq);
}
static struct irq_chip armada_370_xp_msi_irq_chip = {
.name = "armada_370_xp_msi_irq",
.irq_enable = unmask_msi_irq,
.irq_disable = mask_msi_irq,
.irq_mask = mask_msi_irq,
.irq_unmask = unmask_msi_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);
set_irq_flags(virq, IRQF_VALID);
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_chip *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)
{
unsigned long reg;
unsigned long new_mask = 0;
unsigned long online_mask = 0;
unsigned long count = 0;
irq_hw_number_t hwirq = irqd_to_hwirq(d);
int cpu;
for_each_cpu(cpu, mask_val) {
new_mask |= 1 << cpu_logical_map(cpu);
count++;
}
/*
* Forbid mutlicore interrupt affinity
* This is required since the MPIC HW doesn't limit
* several CPUs from acknowledging the same interrupt.
*/
if (count > 1)
return -EINVAL;
for_each_cpu(cpu, cpu_online_mask)
online_mask |= 1 << cpu_logical_map(cpu);
raw_spin_lock(&irq_controller_lock);
reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
reg = (reg & (~online_mask)) | new_mask;
writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq));
raw_spin_unlock(&irq_controller_lock);
return 0;
}
#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
};
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 (hw != ARMADA_370_XP_TIMER0_PER_CPU_IRQ)
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 (hw == ARMADA_370_XP_TIMER0_PER_CPU_IRQ) {
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);
}
set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
return 0;
}
#ifdef CONFIG_SMP
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);
}
void armada_xp_mpic_smp_cpu_init(void)
{
/* 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);
}
#endif /* CONFIG_SMP */
static 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;
irq = irq_find_mapping(armada_370_xp_msi_domain,
msinr - 16);
if (is_chained)
generic_handle_irq(irq);
else
handle_IRQ(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(unsigned int irq,
struct irq_desc *desc)
{
struct irq_chip *chip = irq_get_chip(irq);
unsigned long irqmap, irqn;
unsigned int cascade_irq;
chained_irq_enter(chip, desc);
irqmap = readl_relaxed(per_cpu_int_base + ARMADA_375_PPI_CAUSE);
if (irqmap & BIT(0)) {
armada_370_xp_handle_msi_irq(NULL, true);
irqmap &= ~BIT(0);
}
for_each_set_bit(irqn, &irqmap, BITS_PER_LONG) {
cascade_irq = irq_find_mapping(armada_370_xp_mpic_domain, irqn);
generic_handle_irq(cascade_irq);
}
chained_irq_exit(chip, desc);
}
static asmlinkage 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) {
irqnr = irq_find_mapping(armada_370_xp_mpic_domain,
irqnr);
handle_IRQ(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 __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 parent_irq;
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);
armada_370_xp_mpic_domain =
irq_domain_add_linear(node, (control >> 2) & 0x3ff,
&armada_370_xp_mpic_irq_ops, NULL);
BUG_ON(!armada_370_xp_mpic_domain);
#ifdef CONFIG_SMP
armada_xp_mpic_smp_cpu_init();
/*
* Set the default affinity from all CPUs to the boot cpu.
* This is required since the MPIC doesn't limit several CPUs
* from acknowledging the same interrupt.
*/
cpumask_clear(irq_default_affinity);
cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
#endif
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);
} else {
irq_set_chained_handler(parent_irq,
armada_370_xp_mpic_handle_cascade_irq);
}
return 0;
}
IRQCHIP_DECLARE(armada_370_xp_mpic, "marvell,mpic", armada_370_xp_mpic_of_init);
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