344 lines
8.2 KiB
C
344 lines
8.2 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Root interrupt controller for the BCM2836 (Raspberry Pi 2).
|
|
*
|
|
* Copyright 2015 Broadcom
|
|
*/
|
|
|
|
#include <linux/cpu.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/irqchip.h>
|
|
#include <linux/irqdomain.h>
|
|
#include <linux/irqchip/chained_irq.h>
|
|
#include <linux/irqchip/irq-bcm2836.h>
|
|
|
|
#include <asm/exception.h>
|
|
|
|
struct bcm2836_arm_irqchip_intc {
|
|
struct irq_domain *domain;
|
|
void __iomem *base;
|
|
};
|
|
|
|
static struct bcm2836_arm_irqchip_intc intc __read_mostly;
|
|
|
|
static void bcm2836_arm_irqchip_mask_per_cpu_irq(unsigned int reg_offset,
|
|
unsigned int bit,
|
|
int cpu)
|
|
{
|
|
void __iomem *reg = intc.base + reg_offset + 4 * cpu;
|
|
|
|
writel(readl(reg) & ~BIT(bit), reg);
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_unmask_per_cpu_irq(unsigned int reg_offset,
|
|
unsigned int bit,
|
|
int cpu)
|
|
{
|
|
void __iomem *reg = intc.base + reg_offset + 4 * cpu;
|
|
|
|
writel(readl(reg) | BIT(bit), reg);
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_mask_timer_irq(struct irq_data *d)
|
|
{
|
|
bcm2836_arm_irqchip_mask_per_cpu_irq(LOCAL_TIMER_INT_CONTROL0,
|
|
d->hwirq - LOCAL_IRQ_CNTPSIRQ,
|
|
smp_processor_id());
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_unmask_timer_irq(struct irq_data *d)
|
|
{
|
|
bcm2836_arm_irqchip_unmask_per_cpu_irq(LOCAL_TIMER_INT_CONTROL0,
|
|
d->hwirq - LOCAL_IRQ_CNTPSIRQ,
|
|
smp_processor_id());
|
|
}
|
|
|
|
static struct irq_chip bcm2836_arm_irqchip_timer = {
|
|
.name = "bcm2836-timer",
|
|
.irq_mask = bcm2836_arm_irqchip_mask_timer_irq,
|
|
.irq_unmask = bcm2836_arm_irqchip_unmask_timer_irq,
|
|
};
|
|
|
|
static void bcm2836_arm_irqchip_mask_pmu_irq(struct irq_data *d)
|
|
{
|
|
writel(1 << smp_processor_id(), intc.base + LOCAL_PM_ROUTING_CLR);
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_unmask_pmu_irq(struct irq_data *d)
|
|
{
|
|
writel(1 << smp_processor_id(), intc.base + LOCAL_PM_ROUTING_SET);
|
|
}
|
|
|
|
static struct irq_chip bcm2836_arm_irqchip_pmu = {
|
|
.name = "bcm2836-pmu",
|
|
.irq_mask = bcm2836_arm_irqchip_mask_pmu_irq,
|
|
.irq_unmask = bcm2836_arm_irqchip_unmask_pmu_irq,
|
|
};
|
|
|
|
static void bcm2836_arm_irqchip_mask_gpu_irq(struct irq_data *d)
|
|
{
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_unmask_gpu_irq(struct irq_data *d)
|
|
{
|
|
}
|
|
|
|
static struct irq_chip bcm2836_arm_irqchip_gpu = {
|
|
.name = "bcm2836-gpu",
|
|
.irq_mask = bcm2836_arm_irqchip_mask_gpu_irq,
|
|
.irq_unmask = bcm2836_arm_irqchip_unmask_gpu_irq,
|
|
};
|
|
|
|
static void bcm2836_arm_irqchip_dummy_op(struct irq_data *d)
|
|
{
|
|
}
|
|
|
|
static struct irq_chip bcm2836_arm_irqchip_dummy = {
|
|
.name = "bcm2836-dummy",
|
|
.irq_eoi = bcm2836_arm_irqchip_dummy_op,
|
|
};
|
|
|
|
static int bcm2836_map(struct irq_domain *d, unsigned int irq,
|
|
irq_hw_number_t hw)
|
|
{
|
|
struct irq_chip *chip;
|
|
|
|
switch (hw) {
|
|
case LOCAL_IRQ_MAILBOX0:
|
|
chip = &bcm2836_arm_irqchip_dummy;
|
|
break;
|
|
case LOCAL_IRQ_CNTPSIRQ:
|
|
case LOCAL_IRQ_CNTPNSIRQ:
|
|
case LOCAL_IRQ_CNTHPIRQ:
|
|
case LOCAL_IRQ_CNTVIRQ:
|
|
chip = &bcm2836_arm_irqchip_timer;
|
|
break;
|
|
case LOCAL_IRQ_GPU_FAST:
|
|
chip = &bcm2836_arm_irqchip_gpu;
|
|
break;
|
|
case LOCAL_IRQ_PMU_FAST:
|
|
chip = &bcm2836_arm_irqchip_pmu;
|
|
break;
|
|
default:
|
|
pr_warn_once("Unexpected hw irq: %lu\n", hw);
|
|
return -EINVAL;
|
|
}
|
|
|
|
irq_set_percpu_devid(irq);
|
|
irq_domain_set_info(d, irq, hw, chip, d->host_data,
|
|
handle_percpu_devid_irq, NULL, NULL);
|
|
irq_set_status_flags(irq, IRQ_NOAUTOEN);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
__exception_irq_entry bcm2836_arm_irqchip_handle_irq(struct pt_regs *regs)
|
|
{
|
|
int cpu = smp_processor_id();
|
|
u32 stat;
|
|
|
|
stat = readl_relaxed(intc.base + LOCAL_IRQ_PENDING0 + 4 * cpu);
|
|
if (stat) {
|
|
u32 hwirq = ffs(stat) - 1;
|
|
|
|
handle_domain_irq(intc.domain, hwirq, regs);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_SMP
|
|
static struct irq_domain *ipi_domain;
|
|
|
|
static void bcm2836_arm_irqchip_handle_ipi(struct irq_desc *desc)
|
|
{
|
|
struct irq_chip *chip = irq_desc_get_chip(desc);
|
|
int cpu = smp_processor_id();
|
|
u32 mbox_val;
|
|
|
|
chained_irq_enter(chip, desc);
|
|
|
|
mbox_val = readl_relaxed(intc.base + LOCAL_MAILBOX0_CLR0 + 16 * cpu);
|
|
if (mbox_val) {
|
|
int hwirq = ffs(mbox_val) - 1;
|
|
generic_handle_irq(irq_find_mapping(ipi_domain, hwirq));
|
|
}
|
|
|
|
chained_irq_exit(chip, desc);
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_ipi_ack(struct irq_data *d)
|
|
{
|
|
int cpu = smp_processor_id();
|
|
|
|
writel_relaxed(BIT(d->hwirq),
|
|
intc.base + LOCAL_MAILBOX0_CLR0 + 16 * cpu);
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_ipi_send_mask(struct irq_data *d,
|
|
const struct cpumask *mask)
|
|
{
|
|
int cpu;
|
|
void __iomem *mailbox0_base = intc.base + LOCAL_MAILBOX0_SET0;
|
|
|
|
/*
|
|
* Ensure that stores to normal memory are visible to the
|
|
* other CPUs before issuing the IPI.
|
|
*/
|
|
smp_wmb();
|
|
|
|
for_each_cpu(cpu, mask)
|
|
writel_relaxed(BIT(d->hwirq), mailbox0_base + 16 * cpu);
|
|
}
|
|
|
|
static struct irq_chip bcm2836_arm_irqchip_ipi = {
|
|
.name = "IPI",
|
|
.irq_mask = bcm2836_arm_irqchip_dummy_op,
|
|
.irq_unmask = bcm2836_arm_irqchip_dummy_op,
|
|
.irq_ack = bcm2836_arm_irqchip_ipi_ack,
|
|
.ipi_send_mask = bcm2836_arm_irqchip_ipi_send_mask,
|
|
};
|
|
|
|
static int bcm2836_arm_irqchip_ipi_alloc(struct irq_domain *d,
|
|
unsigned int virq,
|
|
unsigned int nr_irqs, void *args)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_irqs; i++) {
|
|
irq_set_percpu_devid(virq + i);
|
|
irq_domain_set_info(d, virq + i, i, &bcm2836_arm_irqchip_ipi,
|
|
d->host_data,
|
|
handle_percpu_devid_irq,
|
|
NULL, NULL);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void bcm2836_arm_irqchip_ipi_free(struct irq_domain *d,
|
|
unsigned int virq,
|
|
unsigned int nr_irqs)
|
|
{
|
|
/* Not freeing IPIs */
|
|
}
|
|
|
|
static const struct irq_domain_ops ipi_domain_ops = {
|
|
.alloc = bcm2836_arm_irqchip_ipi_alloc,
|
|
.free = bcm2836_arm_irqchip_ipi_free,
|
|
};
|
|
|
|
static int bcm2836_cpu_starting(unsigned int cpu)
|
|
{
|
|
bcm2836_arm_irqchip_unmask_per_cpu_irq(LOCAL_MAILBOX_INT_CONTROL0, 0,
|
|
cpu);
|
|
return 0;
|
|
}
|
|
|
|
static int bcm2836_cpu_dying(unsigned int cpu)
|
|
{
|
|
bcm2836_arm_irqchip_mask_per_cpu_irq(LOCAL_MAILBOX_INT_CONTROL0, 0,
|
|
cpu);
|
|
return 0;
|
|
}
|
|
|
|
#define BITS_PER_MBOX 32
|
|
|
|
static void __init bcm2836_arm_irqchip_smp_init(void)
|
|
{
|
|
struct irq_fwspec ipi_fwspec = {
|
|
.fwnode = intc.domain->fwnode,
|
|
.param_count = 1,
|
|
.param = {
|
|
[0] = LOCAL_IRQ_MAILBOX0,
|
|
},
|
|
};
|
|
int base_ipi, mux_irq;
|
|
|
|
mux_irq = irq_create_fwspec_mapping(&ipi_fwspec);
|
|
if (WARN_ON(mux_irq <= 0))
|
|
return;
|
|
|
|
ipi_domain = irq_domain_create_linear(intc.domain->fwnode,
|
|
BITS_PER_MBOX, &ipi_domain_ops,
|
|
NULL);
|
|
if (WARN_ON(!ipi_domain))
|
|
return;
|
|
|
|
ipi_domain->flags |= IRQ_DOMAIN_FLAG_IPI_SINGLE;
|
|
irq_domain_update_bus_token(ipi_domain, DOMAIN_BUS_IPI);
|
|
|
|
base_ipi = __irq_domain_alloc_irqs(ipi_domain, -1, BITS_PER_MBOX,
|
|
NUMA_NO_NODE, NULL,
|
|
false, NULL);
|
|
|
|
if (WARN_ON(!base_ipi))
|
|
return;
|
|
|
|
set_smp_ipi_range(base_ipi, BITS_PER_MBOX);
|
|
|
|
irq_set_chained_handler_and_data(mux_irq,
|
|
bcm2836_arm_irqchip_handle_ipi, NULL);
|
|
|
|
/* Unmask IPIs to the boot CPU. */
|
|
cpuhp_setup_state(CPUHP_AP_IRQ_BCM2836_STARTING,
|
|
"irqchip/bcm2836:starting", bcm2836_cpu_starting,
|
|
bcm2836_cpu_dying);
|
|
}
|
|
#else
|
|
#define bcm2836_arm_irqchip_smp_init() do { } while(0)
|
|
#endif
|
|
|
|
static const struct irq_domain_ops bcm2836_arm_irqchip_intc_ops = {
|
|
.xlate = irq_domain_xlate_onetwocell,
|
|
.map = bcm2836_map,
|
|
};
|
|
|
|
/*
|
|
* The LOCAL_IRQ_CNT* timer firings are based off of the external
|
|
* oscillator with some scaling. The firmware sets up CNTFRQ to
|
|
* report 19.2Mhz, but doesn't set up the scaling registers.
|
|
*/
|
|
static void bcm2835_init_local_timer_frequency(void)
|
|
{
|
|
/*
|
|
* Set the timer to source from the 19.2Mhz crystal clock (bit
|
|
* 8 unset), and only increment by 1 instead of 2 (bit 9
|
|
* unset).
|
|
*/
|
|
writel(0, intc.base + LOCAL_CONTROL);
|
|
|
|
/*
|
|
* Set the timer prescaler to 1:1 (timer freq = input freq *
|
|
* 2**31 / prescaler)
|
|
*/
|
|
writel(0x80000000, intc.base + LOCAL_PRESCALER);
|
|
}
|
|
|
|
static int __init bcm2836_arm_irqchip_l1_intc_of_init(struct device_node *node,
|
|
struct device_node *parent)
|
|
{
|
|
intc.base = of_iomap(node, 0);
|
|
if (!intc.base) {
|
|
panic("%pOF: unable to map local interrupt registers\n", node);
|
|
}
|
|
|
|
bcm2835_init_local_timer_frequency();
|
|
|
|
intc.domain = irq_domain_add_linear(node, LAST_IRQ + 1,
|
|
&bcm2836_arm_irqchip_intc_ops,
|
|
NULL);
|
|
if (!intc.domain)
|
|
panic("%pOF: unable to create IRQ domain\n", node);
|
|
|
|
irq_domain_update_bus_token(intc.domain, DOMAIN_BUS_WIRED);
|
|
|
|
bcm2836_arm_irqchip_smp_init();
|
|
|
|
set_handle_irq(bcm2836_arm_irqchip_handle_irq);
|
|
return 0;
|
|
}
|
|
|
|
IRQCHIP_DECLARE(bcm2836_arm_irqchip_l1_intc, "brcm,bcm2836-l1-intc",
|
|
bcm2836_arm_irqchip_l1_intc_of_init);
|