kernel-fxtec-pro1x/drivers/irqchip/irq-mscc-ocelot.c
Alexandre Belloni 19d9916448 irqchip: Add a driver for the Microsemi Ocelot controller
The Microsemi Ocelot SoC has a pretty simple IRQ controller in its ICPU
block. Add a driver for it.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-22 15:52:27 +00:00

118 lines
3.1 KiB
C

// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/*
* Microsemi Ocelot IRQ controller driver
*
* Copyright (c) 2017 Microsemi Corporation
*/
#include <linux/bitops.h>
#include <linux/irq.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/interrupt.h>
#define ICPU_CFG_INTR_INTR_STICKY 0x10
#define ICPU_CFG_INTR_INTR_ENA 0x18
#define ICPU_CFG_INTR_INTR_ENA_CLR 0x1c
#define ICPU_CFG_INTR_INTR_ENA_SET 0x20
#define ICPU_CFG_INTR_DST_INTR_IDENT(x) (0x38 + 0x4 * (x))
#define ICPU_CFG_INTR_INTR_TRIGGER(x) (0x5c + 0x4 * (x))
#define OCELOT_NR_IRQ 24
static void ocelot_irq_unmask(struct irq_data *data)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
struct irq_chip_type *ct = irq_data_get_chip_type(data);
unsigned int mask = data->mask;
u32 val;
irq_gc_lock(gc);
val = irq_reg_readl(gc, ICPU_CFG_INTR_INTR_TRIGGER(0)) |
irq_reg_readl(gc, ICPU_CFG_INTR_INTR_TRIGGER(1));
if (!(val & mask))
irq_reg_writel(gc, mask, ICPU_CFG_INTR_INTR_STICKY);
*ct->mask_cache &= ~mask;
irq_reg_writel(gc, mask, ICPU_CFG_INTR_INTR_ENA_SET);
irq_gc_unlock(gc);
}
static void ocelot_irq_handler(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
struct irq_domain *d = irq_desc_get_handler_data(desc);
struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0);
u32 reg = irq_reg_readl(gc, ICPU_CFG_INTR_DST_INTR_IDENT(0));
chained_irq_enter(chip, desc);
while (reg) {
u32 hwirq = __fls(reg);
generic_handle_irq(irq_find_mapping(d, hwirq));
reg &= ~(BIT(hwirq));
}
chained_irq_exit(chip, desc);
}
static int __init ocelot_irq_init(struct device_node *node,
struct device_node *parent)
{
struct irq_domain *domain;
struct irq_chip_generic *gc;
int parent_irq, ret;
parent_irq = irq_of_parse_and_map(node, 0);
if (!parent_irq)
return -EINVAL;
domain = irq_domain_add_linear(node, OCELOT_NR_IRQ,
&irq_generic_chip_ops, NULL);
if (!domain) {
pr_err("%s: unable to add irq domain\n", node->name);
return -ENOMEM;
}
ret = irq_alloc_domain_generic_chips(domain, OCELOT_NR_IRQ, 1,
"icpu", handle_level_irq,
0, 0, 0);
if (ret) {
pr_err("%s: unable to alloc irq domain gc\n", node->name);
goto err_domain_remove;
}
gc = irq_get_domain_generic_chip(domain, 0);
gc->reg_base = of_iomap(node, 0);
if (!gc->reg_base) {
pr_err("%s: unable to map resource\n", node->name);
ret = -ENOMEM;
goto err_gc_free;
}
gc->chip_types[0].regs.ack = ICPU_CFG_INTR_INTR_STICKY;
gc->chip_types[0].regs.mask = ICPU_CFG_INTR_INTR_ENA_CLR;
gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
gc->chip_types[0].chip.irq_unmask = ocelot_irq_unmask;
/* Mask and ack all interrupts */
irq_reg_writel(gc, 0, ICPU_CFG_INTR_INTR_ENA);
irq_reg_writel(gc, 0xffffffff, ICPU_CFG_INTR_INTR_STICKY);
irq_set_chained_handler_and_data(parent_irq, ocelot_irq_handler,
domain);
return 0;
err_gc_free:
irq_free_generic_chip(gc);
err_domain_remove:
irq_domain_remove(domain);
return ret;
}
IRQCHIP_DECLARE(ocelot_icpu, "mscc,ocelot-icpu-intr", ocelot_irq_init);