diff options
Diffstat (limited to 'drivers/irqchip/irq-mchp-eic.c')
| -rw-r--r-- | drivers/irqchip/irq-mchp-eic.c | 280 | 
1 files changed, 280 insertions, 0 deletions
| diff --git a/drivers/irqchip/irq-mchp-eic.c b/drivers/irqchip/irq-mchp-eic.c new file mode 100644 index 000000000000..c726a19837d2 --- /dev/null +++ b/drivers/irqchip/irq-mchp-eic.c @@ -0,0 +1,280 @@ +// 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_LICENSE("GPL v2"); +MODULE_AUTHOR("Claudiu Beznea <claudiu.beznea@microchip.com>"); | 
