linux/drivers/irqchip/irq-mchp-eic.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Microchip External Interrupt Controller driver
*
* Copyright (C) 2021 Microchip Technology Inc. and its subsidiaries
*
* Author: Claudiu Beznea <claudiu.beznea@microchip.com>
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/irqchip.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/syscore_ops.h>
#include <dt-bindings/interrupt-controller/arm-gic.h>
#define MCHP_EIC_GFCS (0x0)
#define MCHP_EIC_SCFG(x) (0x4 + (x) * 0x4)
#define MCHP_EIC_SCFG_EN BIT(16)
#define MCHP_EIC_SCFG_LVL BIT(9)
#define MCHP_EIC_SCFG_POL BIT(8)
#define MCHP_EIC_NIRQ (2)
/*
* struct mchp_eic - EIC private data structure
* @base: base address
* @clk: peripheral clock
* @domain: irq domain
* @irqs: irqs b/w eic and gic
* @scfg: backup for scfg registers (necessary for backup and self-refresh mode)
* @wakeup_source: wakeup source mask
*/
struct mchp_eic {
void __iomem *base;
struct clk *clk;
struct irq_domain *domain;
u32 irqs[MCHP_EIC_NIRQ];
u32 scfg[MCHP_EIC_NIRQ];
u32 wakeup_source;
};
static struct mchp_eic *eic;
static void mchp_eic_irq_mask(struct irq_data *d)
{
unsigned int tmp;
tmp = readl_relaxed(eic->base + MCHP_EIC_SCFG(d->hwirq));
tmp &= ~MCHP_EIC_SCFG_EN;
writel_relaxed(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
irq_chip_mask_parent(d);
}
static void mchp_eic_irq_unmask(struct irq_data *d)
{
unsigned int tmp;
tmp = readl_relaxed(eic->base + MCHP_EIC_SCFG(d->hwirq));
tmp |= MCHP_EIC_SCFG_EN;
writel_relaxed(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
irq_chip_unmask_parent(d);
}
static int mchp_eic_irq_set_type(struct irq_data *d, unsigned int type)
{
unsigned int parent_irq_type;
unsigned int tmp;
tmp = readl_relaxed(eic->base + MCHP_EIC_SCFG(d->hwirq));
tmp &= ~(MCHP_EIC_SCFG_POL | MCHP_EIC_SCFG_LVL);
switch (type) {
case IRQ_TYPE_LEVEL_HIGH:
tmp |= MCHP_EIC_SCFG_POL | MCHP_EIC_SCFG_LVL;
parent_irq_type = IRQ_TYPE_LEVEL_HIGH;
break;
case IRQ_TYPE_LEVEL_LOW:
tmp |= MCHP_EIC_SCFG_LVL;
parent_irq_type = IRQ_TYPE_LEVEL_HIGH;
break;
case IRQ_TYPE_EDGE_RISING:
parent_irq_type = IRQ_TYPE_EDGE_RISING;
break;
case IRQ_TYPE_EDGE_FALLING:
tmp |= MCHP_EIC_SCFG_POL;
parent_irq_type = IRQ_TYPE_EDGE_RISING;
break;
default:
return -EINVAL;
}
writel_relaxed(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
return irq_chip_set_type_parent(d, parent_irq_type);
}
static int mchp_eic_irq_set_wake(struct irq_data *d, unsigned int on)
{
irq_set_irq_wake(eic->irqs[d->hwirq], on);
if (on)
eic->wakeup_source |= BIT(d->hwirq);
else
eic->wakeup_source &= ~BIT(d->hwirq);
return 0;
}
static int mchp_eic_irq_suspend(void)
{
unsigned int hwirq;
for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++)
eic->scfg[hwirq] = readl_relaxed(eic->base +
MCHP_EIC_SCFG(hwirq));
if (!eic->wakeup_source)
clk_disable_unprepare(eic->clk);
return 0;
}
static void mchp_eic_irq_resume(void)
{
unsigned int hwirq;
if (!eic->wakeup_source)
clk_prepare_enable(eic->clk);
for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++)
writel_relaxed(eic->scfg[hwirq], eic->base +
MCHP_EIC_SCFG(hwirq));
}
static struct syscore_ops mchp_eic_syscore_ops = {
.suspend = mchp_eic_irq_suspend,
.resume = mchp_eic_irq_resume,
};
static struct irq_chip mchp_eic_chip = {
.name = "eic",
.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SET_TYPE_MASKED,
.irq_mask = mchp_eic_irq_mask,
.irq_unmask = mchp_eic_irq_unmask,
.irq_set_type = mchp_eic_irq_set_type,
.irq_ack = irq_chip_ack_parent,
.irq_eoi = irq_chip_eoi_parent,
.irq_retrigger = irq_chip_retrigger_hierarchy,
.irq_set_wake = mchp_eic_irq_set_wake,
};
static int mchp_eic_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *data)
{
struct irq_fwspec *fwspec = data;
struct irq_fwspec parent_fwspec;
irq_hw_number_t hwirq;
unsigned int type;
int ret;
if (WARN_ON(nr_irqs != 1))
return -EINVAL;
ret = irq_domain_translate_twocell(domain, fwspec, &hwirq, &type);
if (ret || hwirq >= MCHP_EIC_NIRQ)
return ret;
switch (type) {
case IRQ_TYPE_EDGE_RISING:
case IRQ_TYPE_LEVEL_HIGH:
break;
case IRQ_TYPE_EDGE_FALLING:
type = IRQ_TYPE_EDGE_RISING;
break;
case IRQ_TYPE_LEVEL_LOW:
type = IRQ_TYPE_LEVEL_HIGH;
break;
default:
return -EINVAL;
}
irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &mchp_eic_chip, eic);
parent_fwspec.fwnode = domain->parent->fwnode;
parent_fwspec.param_count = 3;
parent_fwspec.param[0] = GIC_SPI;
parent_fwspec.param[1] = eic->irqs[hwirq];
parent_fwspec.param[2] = type;
return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
}
static const struct irq_domain_ops mchp_eic_domain_ops = {
.translate = irq_domain_translate_twocell,
.alloc = mchp_eic_domain_alloc,
.free = irq_domain_free_irqs_common,
};
static int mchp_eic_init(struct device_node *node, struct device_node *parent)
{
struct irq_domain *parent_domain = NULL;
int ret, i;
eic = kzalloc(sizeof(*eic), GFP_KERNEL);
if (!eic)
return -ENOMEM;
eic->base = of_iomap(node, 0);
if (!eic->base) {
ret = -ENOMEM;
goto free;
}
parent_domain = irq_find_host(parent);
if (!parent_domain) {
ret = -ENODEV;
goto unmap;
}
eic->clk = of_clk_get_by_name(node, "pclk");
if (IS_ERR(eic->clk)) {
ret = PTR_ERR(eic->clk);
goto unmap;
}
ret = clk_prepare_enable(eic->clk);
if (ret)
goto unmap;
for (i = 0; i < MCHP_EIC_NIRQ; i++) {
struct of_phandle_args irq;
/* Disable it, if any. */
writel_relaxed(0UL, eic->base + MCHP_EIC_SCFG(i));
ret = of_irq_parse_one(node, i, &irq);
if (ret)
goto clk_unprepare;
if (WARN_ON(irq.args_count != 3)) {
ret = -EINVAL;
goto clk_unprepare;
}
eic->irqs[i] = irq.args[1];
}
eic->domain = irq_domain_add_hierarchy(parent_domain, 0, MCHP_EIC_NIRQ,
node, &mchp_eic_domain_ops, eic);
if (!eic->domain) {
pr_err("%pOF: Failed to add domain\n", node);
ret = -ENODEV;
goto clk_unprepare;
}
register_syscore_ops(&mchp_eic_syscore_ops);
pr_info("%pOF: EIC registered, nr_irqs %u\n", node, MCHP_EIC_NIRQ);
return 0;
clk_unprepare:
clk_disable_unprepare(eic->clk);
unmap:
iounmap(eic->base);
free:
kfree(eic);
return ret;
}
IRQCHIP_PLATFORM_DRIVER_BEGIN(mchp_eic)
IRQCHIP_MATCH("microchip,sama7g5-eic", mchp_eic_init)
IRQCHIP_PLATFORM_DRIVER_END(mchp_eic)
MODULE_DESCRIPTION("Microchip External Interrupt Controller");
MODULE_AUTHOR("Claudiu Beznea <claudiu.beznea@microchip.com>");